uratom bulletin of the european atomic energy community september 1966 vol. V no. 3 ^-^"^

May 17, 1955 E. FERMI ETAL 2,708,656 NEUTRONIC REACTOR Filed Dec. 19, 1944 27 Sheets-Sheet 25

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Quarterly Information Bulletin of the Euro­ pean Atomic Energy Community (Euratom)

Published and edited by

Euratom, Dissemination of Information Directorate, 51-53 rue Belliard, Brussels 4. Telephone: 13 40 90

1966-3

Contents:

66 Desalination today and tomorrow 73 A food irradiation pilot plant 76 Euratom and patents 80 Low-energy nuclear physics and the development of nuclear applications 85 Nuclear energy insurance 92 Euratom news:

Ivory Coast and Chad—means for preservation of fish and meat by irradiation; Fuel for Lingen, Dode- waard and Obrigheim reactors; A comprehensive study of pressurised-water reactors; A prototype isotope generator; Collaboration in the field of direct conversion; Uranium prospecting in the Com­ munity; Petten HFR reactor uprated ; Euratom Econom­ ic Handbook; Radioisotopes for detecting wear in Diesel engines; The CIRENE design; uranium metal or oxide? Scientific and technical documentation takes a step forward; Five-year index to "Transatom Bulletin".

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Van de Graaffaccelerator at the Joint Research Centre's Geel Establishment (Belgium). The Euratom Commission or any persons acting on its behalf disclaim all liability with respect to the completeness of the in· formation contained In this periodical as well as to any damage which might result from the use of information disclosed or of equipment, methods or processes described therein.

Any article published In this bulletin may be reproduced in whole or in part without restriction, provided that the source is mentioned.

Picture credits: Page 2 of cover: SADO, Brussels; page 80: Publifoto, Milan; page 89: Euratom JRC, Ispra/U. Zimmermann; Publi• foto, Rome; page 91: Pierre Jahan, France; page 93: KLM Aerocarto N.V., Netherlands; AEG, Germany. Art-work by Gaston Bogaert, Brussels.

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Printed In the Netherlands by A. W. Sijthoff, Leiden To maintain that fresh water is essential to man, for his own consumption, for domestic purposes and for use in agriculture and industry, would be to state the obvious. However, it is by no means so obvious that recourse will have to be made to desalination of sea-water and brackish water in order to obtain it in sufficient quan• tities.

The general opinion is that this is true in certain areas of Quarterly Information Bulletin of the the world which have a dry climate and where economic European Atomic Energy Community growth would be impossible without desalination, but (Euratom) our countries, with their temperate climate . . .? The fact that the Euratom Bulletin has called upon the serv• ices of an eminent expert from Israel in order to out• line the desalination problem in this number almost provides confirmation of this attitude.

1966- However, the truth of the matter, as things stand at present, is that in about ten years' time desalination will have to be carried out on a large scale in certain parts of the Community. This, at least, is the conclusion to be drawn from aseries of studies recently launched by Euratom.

An example to illustrate this is the growing industrial zone in the Bari-Brindisi-Taranto triangle, where it is estimated that the daily demand for fresh water will have increased by several hundred thousand cubic metres in ten years' time, it being likely that this quantity can only be produced at a reasonable cost by means of desalination. North Germany at present adds to its local resources by piping in water from moun• tainous areas situated about one hundred and fifty miles from the point at which it is consumed, so that desali• nation holds out promise of offering a less expensive means of obtaining fresh water. In Belgium, public opinion is hostile to the erection of dams, which are nonetheless necessary for meeting water supply re• quirements, on account of which desalination offers an attractive alternative.

It is a known fact that the best economic prospects lie in The Community's mission is to create the conditions necessary for the speedy estab• the construction of large combined plants, in which lishment and growth of nuclear industries nuclear energy could be used to produce both electricity in the member States and thereby contrib• and fresh water. We will return to this aspect of the ute to the raising of living standards and matter once the studies mentioned above are com• the development of exchanges with other pleted. countries (Article 1 of the Treaty instituting the European Atomic Energy Communityjnityj) . EU BU 5-10

Main desalination processes

Present desalination processes can be di• vided into four main types: electrodialysis, reverse osmosis, freezing and evaporation. In all these processes, which either separate Desalination today and solvent (water) from solute (salt) or vice- versa, a theoretical minimum amount of thermodynamic energy must be invested. The minimum energy requirement is rel• atively small (e.g. 0.7 kilowatt-hours per tomorrow cubic metre for a salinity of 3.43% at 25°) and is the same for all processes.

I.E. STREIFLER-SHAVIT, Project Manager, The Joint Sea-Water Desalting Project, Israel Electrodialysis

Electrodialytic desalting is carried out in a series of water-filled compartments sep• arated by special "permselective" mem• branes, of two different types. If an elec• tric current is passed through the water, one type of membrane lets through water Water resources are running out from its present inconspicuity and consti• and cations, but stops anions; the other lets tute an integrated part of our environ• through water and anions only. As can be The existence of unlimited water resources ment, helped by the increasing availability seen from figure 2, the membranes are was taken for granted in the past, and of cheap energy from large power plants. arranged so that the salt concentration little attention has therefore been paid in Admittedly, sea-water conversion technol• rises in half of the compartments and sinks most parts of the world to the manage• ogy will have to be developed at the price correspondingly in the others. ment of regional water supplies. Allocation of considerable efforts, but it holds out A feature of electrodialysis is that it does of water resources in arid zones has been great promise for the satisfaction of man• not involve a change of phase of the water. and continues nowadays to be a cause of kind's future water needs. When the method was first introduced. dispute among neighbouring nations. Cities like New York already experience severe water shortages, while others are threatened and most concerned about their future. The state of California faces in its north the problem of harnessing run off water, which causes loss of life and property, while in the arid south water resources are becoming depleted. Large water conveyance and pump• ing schemes are therefore being contem• plated and are expected to meet the pro• jected water need for the next two decades.

Water is becoming a raw material

In short, water will soon have to be regard• ed, not as a commodity In unlimited supply, but as a raw material to which an adequate value will have to be assigned. This will call for certain economic adjust• ments. The development and management of water resources will be an important fac• tor of international co-operation on a scale determined by climatic zones. The water conversion industry will emerge

66 it was thought that this would constitute an advantage, because it seemed that, thanks to the reduction of frictional energy losses to negligible proportions, energy consumption would approach the theoreti• cal minimum. However, here as in other methods, energy is wasted: polarisation and electrical resistance must be com• pensated; scaling and filtration problems must be solved, back diffusion of salt must be overcome and membranes replaced. As energy consumption with this method is proportional to the salt content of water, electrodialysis should logically be used for conversion of slightly brackish water or waste only, although attempts to use it for sea-water desalting, by itself, or in com• Figure 2 : Working principle of electrodialysis bination with other methods, are being made.

Only one plant in the range of 2000 cubic metres per day is in operation today This projected figure refers to the local phenomenon is reversed and the solvent can (on brackish water), and it is therefore brackish water with a salinity content of be made to flow through the membrane difficult to evaluate actual costs of this 2000 ppm and a 500 ppm salinity of product from the more concentrated to the less process. Extensive research in this field water. Capital costs for electrodialysis concentrated solution; hence the name is being conducted by the Negev Institute are estimated at about $ 1.00 per litre "reverse osmosis". for Arid Zone Research in Israel. One 500 product per hour for a 30% reduction in Efforts have been devoted to the improve- cubic metres per day experimental plant salinity. A reduction from 3,000 ppm mentof the membranes used (they are made is in operation and a production plant for brackish water to 500 ppm product water of porous acetyl cellulose) to make them 5000 cubic metres per day is in its final would require five steps, amounting to suitable for the conversion of sea-water planning stages. The water cost for this an investment of $ 5.00 per litre product and brackish water and the purification case amounts to 20 cents per cubic metre. per hour. of waste water. Electrodialysis today can hardly be con• Reverse osmosis has recently emerged sidered a suitable method for upscaling from the laboratory stage. Pilot plants into large production plants for the treat• designed for several cubic metres per day ment of brackish water, and far less for are in operation at present and one for sea-water desalting. 200 cubic metres per day has been planned. The application of reverse osmosis to sea-water requires a pressure of more Reverse osmosis than 100 atmospheres, which places a rigorous demand on the membranes. The phenomenon of osmosis occurs when As large membrane surfaces are required two solutions of different concentrations for sea-water desalting, special ways had are separated by a membrane. If the mem• to be found of accommodating them into brane is "semi-permeable", i.e. ¡f it is limited volumes and of providing the permeable to the solvent (water) and not necessary resistance to high pressure. to the solute (salt), a flow of solvent occurs Membranes yield about 200 litres of prod• from the more dilute into the more con• uct water per square metre of surface per centrated solution until the concentration day. As membranes constitute the main becomes the same for both solutions or cost factor and still have to be frequently until the pressure of the more concen• replaced, cost estimates are difficult to trated solution rises to a certain value. arrive at. The current estimate of water However, if extra pressure is applied to produced is 25 cents per cubic metre in a the more concentrated solution, the visualised reverse osmosis plant consisting of five major systems: intake, filtration and acid treatment units, high-pressure pumps, reverse osmosis units, power recovery turbines and water discharge Figure 1: Bird's eye view of the Vacuum systems. Vapour Compression Freezing Plant in Eilat.

67 Freezing 700 Mw-th The freezing process, which is currently Power only 200 MWe (net) under development in various directions, is similar to electrodialysis in that it is very promising on paper but has encoun­ tered many limitations in practice. It is basically a process involving three phase changes and operates at the "triple 1025 MW-th point" where the liquid, vapour and solid Water only 120 million mPjyear phases coexist. At the "triple point" of -1.9°C under a vacuum of 3.94 mm Hg, 7.5 kilograms of ice are formed for 1 kilogram of vapour from introduced sea-water, according to the corresponding caloric 1250 Mwth values of evaporation and freezing. Dissolved salts remain in the concentrated brine, which in part strongly adheres to the ice Dual-purpose — 200 MWe (net) and 120 crystals formed, and has to be washed million m'jyear away with product water. The "vacuum vapour compression freezing Figure 4: Energy requirements of a dual-pur­ process" has been developed to a most pose plant advanced stage by Desalting Engineering of Israel (Zarchin Process) Ltd., partly in co-operation with Colt Industries Inc. of the large flow volumes (approximately 10,000 Multiple stage flash process United States. It consists of five major cubic metres per minute for a 400 cubic systems: intake, freezer and compressor metres per day plant.) Handling of such Evaporation processes have been in practi­ (hydroconverter), counterwasher, heat huge volumes thus presents a technical cal use for some decades and have been exchangers and process pumps. limitation to possible upscaling of this developed in various forms. The multiple A combination of these relatively simple process. stage flash process is at its present stage elements into a production plant has been The energy requirement is about 12 kilo­ of development the most suitable for use recently finalised and a pilot plant produc­ watt-hours per cubic metre and capital in large scale units. The process consists ing 4 χ 250 cubic metres per day is now in investment is $ 500 per cubic metre in a of three major sections: heat input, heat operation on the Red Sea shore in Israel, plant consisting of 4 modules of 400 cubic recovery, and heat rejection. supplying drinking water to the town of metres each. The estimated water cost for It is a regenerative evaporating process Eilat (figure 1). a plant producing 2000 cubic metres per day, in which latent heat of the vapour leaving In this process the vapour mass flow is assuming a cost of 10 mills per kilowatt- the flashing brine is recovered by the approximately 13% of the ice produced; hour and a 10% fixed charge rate, is 33 recycle brine flowing inside the heat however, its low density results in very cents per cubic metre. transfer tubes (see figure 3). Flow of the

Figure 3: Working principle of the multiple stage flash process. 1. sea-water -\- recycled brine 2. steam heater 3. brine from flashing chambers 4. condensed vapour from flashing chambers (product water)

68 two brine streams, inside and along the adjacent stages is required, which limits An analysis of capital investment of a large flashing chamber, is countercurrent, and a the number of stages possible for any fixed multiple stage flash evaporator demon• temperature difference between the va• temperature range. The number of flashing strates the following division: pour and the recycle brine is maintained by chambers employed, in turn, fixes the - Heat transfer area 35% division into stages. In each stage a pressure economy of the process. The "economy - Steel-work 37% is established as a function of flashing ratio" is defined as kilograms of product - Pumps and other equipment 28% brine temperature. Air and other non- water produced per kilogram of steam The most promising area for future eco• condensable gases are continuously removed added to the brine heater. nomy in investment costs is heat transfer by an evacuation system to maintain the Economy ratio and water costs are closely technology. Direct contact heat transfer, desired pressure drop along the stages. related and affected mainly by the capital when more developed, will open addi• Heat has to be added to the process to investment and energy cost applied. If the tional far-reaching prospects for this pro• compensate for heat removed by cooling unit cost of steam is fixed, a higher fixed cess, as both capital and operating costs water, blow-down and product water. charge rate will lead to a plant which has will drop sharply. It is added by steam from an external fewer flashing chambers but uses more Even within the framework of present source condensing in the brine heater. steam and vice versa. design principles, many elements can be The process has two temperature limits, Many improvements, most of them in improved by further research and devel• that of the sea-water and that of the detail engineering, have been applied to opment work. (The objectives for improve• maximum brine temperature which is the multiple stage flash evaporating pro• ment are: optimum flashing chamber attainable without risking scale formation. cess during the last decade. Further radi• geometry including maximum possible The maximum temperature practical today cal technical improvements to decrease mass flow of brine, maximum vapour disen• is about 120°C and depends on the com• the water cost in this method are limited, gaging rate, minimum temperature and position of the sea-water and the chemical owing to the linear relationship of most pressure drops between two adjacent stages treatment used. of its parameters; nevertheless many and adequate flashing devices, improve• A minimum pressure difference between technical advances are expected. ments in scale prevention methods, and

Figure 5: Dual-purpose power and water the heated brine enters the first chamber of sea-water make-up repeats the circuit. desalting plant. the multi-stage flash evaporator, flashing The recycle stream has a flow seven to ten occurs (because of the reduced pressure in the times the fresh water production rate and a 1 Nuclear reactor chamber), thereby reducing the temperature salt concentration about twice that of sea- 2 Steam generotor of the brine. As the brine flows from chamber water. It is thanks to the blow-down of brine 3 Turbo-generator to chamber, the pressure is progressively to the sea and the addition of the sea-water 4 Electrical energy output lower so that flashing occurs in each succeed• make-up that the recycle concentration and 5 Brine heater ing chamber. During this flow about 10% of flash chamber levels are maintained. The 6 Multi-stage flash evaporator the water in the brine solution is vaporised high purity product water emerges from the 7 Brine recycle pump and subsequently condensed to form fresh wa• heat reject stage at about 32°C. Figure 7 8 Brine blow-down ter. The brine recycle is further cooled in represents a cross-section of two stages in the 9 Sea-water for cooling the reject stage and with the addition of multi-stage flash evaporator. 10 Cooling water pump 11 Sea-water make-up 12 Heat reject stage 13 Fresh water 14 Cooling water to the sea

Incoming sea-water shown in the lower right is used as coolant in the heat reject stage - and a portion of this sea-water coolant is added to the recycling brine as make-up. The recycled brine and sea-water make-up are cooled to 32°C by flashing in the heat reject stage, from where they are pumped into the tube bundles crossing the top part of the multi• stage flash evaporator, causing the vapour produced in the evaporator to condense. The recycled brine, which recovers heat in the pro• cess, emerges from the tubes at over 90°C and is further heated by the condensing steam from the turbine exhaust to about 104°C. As

69 Capacity 120 million m3/ Figure 6: Dual-purpose power and water-desalting plant for Israel (study sponsored jointly year (at 85% by the United States and Israel Governments. -Prime contractor: Kaiser Engineers. - Subcon• plant factor) tractor: Catalytic Construction Company.) Trains 4 (4 modules each) Stages 31 Maximum brine 220°F (104.4°C) temperature Nuclear reactor Economy ratio 10.3 lb water/ 1,000 Btu heat (18,4 kg/1,000 kilocalories) Steam flow to brine 3.4 million Ib/hr heater (1.54 million kg/ hr) Steam pressure at brine 25 psi a heater (1.7 ata) Tube bundles 7/8 inch diameter 90-10 copper/ nickel alloy Chlorine consumption 140 metric tons/ year Sulfuric acid 33,000 metric tons/year.

more efficient deaeration devices). Large dual-purpose plant study power and water producing plant. Another way of reducing water cost signif• The basis for the study were: icantly consists in combining water and A recently completed feasibility study for a — a plant capacity of 175-200 megawatts of power production in a dual-purpose plant. nuclear fired dual-purpose power/water net salable electricity and 100-150 mil• The economy ratio of a single-purpose plant for Israel illustrates, among other lion cubic metres of water per year; water plant is low, owing to the above- findings, the advantage of a large combined — a plant ready for operation in 1971 and mentioned temperature limitations, but the plant (see figure 4). An important additional commercial production in 1972. combined facility will utilise the energy saving accrues from the fact that only one energy source is required, instead of two input over a wider temperature range and The selected plant therefore yield a higher overall efficiency. smaller ones, and that the two plants can be A small dual-purpose water/power produc• run by a joint operational staff. The feasibility study resulted in the "select• ing plant has been erected in the town of The above-mentioned study was undertaken ed plant" which ¡s a nuclear power/desalina• Eilat. This single plant, whose capacities are by an U.S./Israel joint Board. In December tion complex using a light water reactor, 6000 kilowatts and 1.1 million cubic metres 1964, Kaiser Engineers and its main sub• a back-pressure turbine and a multi-stage per year, provides the main water supply contractor, Catalytic Construction Co. of flash evaporator with capacities of 200 for Eilat. Provision has been made for a Philadelphia, were awarded a contract for electrical megawatts (net salable) and 120 second unit of the same capacity. a detailed feasibility study of a dual-purpose million cubic metres per year of water

Figure 7 : Cross-section of two stages in the multi-stage flash evaporator. The heated brine (1) flashes and the vapour which it releases is condensed into fresh water (2) by the tube-bundle (3), through which cooled brine is recirculated. The partition be• tween the two chambers is so arranged that the water seals them off from each other.

70 Figure 8: Israel dual-purpose plant investment (in millions of dollars) Total investment $187,000,000

Power plant

Working capital

Interest during construction

Engineering and owner's cost

General plant characteristics and cost. The study showed Desalting plant that the cost of water produced in a nuclear dual-purpose plant was lower than that produced in a fossil fuel dual-purpose plant for all fixed charge rates (5%, 7% and 10%) Figure9: Split-up of Israel dual-purpose plant considered, when the water plant capacity annual costs was 120 million cubic metres per year. In a companion study at 100 million cubic metres Fixed charges per year the nuclear plant yielded cheaper water for all fixed charge rates below 9%. insurance Estimated capital and unit water costs Depreciation ƒ30 yeors) The estimated capital cost for the selected Fuel dual-purpose plant constructed in Israel is $ 187 million based on 1965 costs and Supplies and materials reflects Israeli construction costs. Allowance

Staff has been made for maximum practical utilisation of Israeli skills, construction Interim replacement labour, materials and products. This capital cost estimate is delineated in Interest figure 8; it does not include electrical transmission and water conveyance facili• ties required to bridge the gap from the dual-purpose plant boundaries to the main production at an 85% plant operating fac• of four trains each having a capacity of 30 Israel distribution network. Therefore, to tor. Figure 5 represents the basic flow million cubic metres per year and each this $ 187 million estimate we may add sheet for this dual-purpose system. capable of operating independently of each $ 5 million for electrical transmission and Main elements of this system (see figure 6) other. Within each train there are four 25 million dollars for water conveyance include the nuclear reactor and power module-trains operating in parallel, each facilities. plant, desalination evaporators, sea-water having a capacity of some 7.5 million cubic The unit water cost estimates are based on intake and acid treatment facilities, product metres per year and representing a four• 1965 costs with respect to operating labour, water storage and facilities for the disposal fold capacity scale-up of existing plants of materials and creditfor powersold (assumed of waste brine. The flow streams connect• this kind. at 5.3 mills per kilowatt-hour) and with ing these elements are arranged to produce Site erection is assumed for evaporator respect to the capital costs upon which electrical power and desalted water at structures, which are made of either rein• the fixed charges have been calculated. As minimum cost. Steam generated in the forced concrete or steel, while such equip• noted in figure 9, fixed charges constitute nuclear reactor plant, depicted in the upper ment as brine heaters, removable evapo• a large portion of the total annual costs. As• left of Figure 5, drives the turbo-generator. rator heat exchange bundles, pumps, air suming an 85% plant operating factor, The steam exhaust from the turbine trans• ejectors, gantry crane, etc. are shop fabric• product water at the plant boundary is fers make-up heat to recycled brine prepar• ated. Design is such that, if the turbo• estimated to cost: atory to the multi-stage evaporation and generator of the power plant is shut down, Fixed charge rates desalting operation. As the flash evaporator the water plant can continue to operate; 5% 7% 10% uses the brine recycle principle, this re• conversely, if the water plant must be shut stricts boiling to the open flash chambers down, the turbo-generator can continue Cents per 1000 gallons 28.6 43.4 67.0 and avoids scaling of tube surfaces. to generate power. Cents per cubic metre 7.6 11.5 17.7 It was on the basis of the computer optimis• ation that a nuclear plant of 1.250 mega• Thus, it is noted that a change of one per• Optimisation studies watts thermal, with a 250 megawatts elec• centage point in fixed charges results in a trical (200 net salable) turbo-generator, difference of about 7.5 cents perl 000 gallons Because of the need to examine plants over supplying steam at 25 psia to the desalting (2.0 cents per cubic metre) in water cost. a large range of physical and economic plant, was chosen. Interest and sinking fund depreciation parameters, a computer programme was (with its heavy dependence on interest devised to permit the evaluation of several Nuclear versus fossil fuel rate) constitute almost the entire fixed thousand alternative plants in a reasonable charge. For example, with a fixed charge time and to determine the combination After selection of the nuclear dual-purpose rate of 7%, interest is 4.6% and deprecia• of characteristics yielding the lowest unit plant, a fossil fuel dual-purpose plant was tion on a 30-year sinking-fund basis is 1.6% water cost. The reference plant consists studied and compared with respect to| ■—together constituting 90% of the total

71 fixed charges. Insurance and in lieu taxes up economies which are possible for desalt• compose another 10%. ing technology. As for the actual applica• A development programme has been recom• tion of product water from dual-purpose mended. This programme will "prove out" plants for municipal, industrial and agri• those features not currently in commercial cultural supply, it will provide information operation and provide data on means of for plants of the more distant future. reducing desalination plant costs. There are many questions which should be Results from a similar feasibility study for considered carefully before deciding on the the Metropolitan Water District of Southern erection of a dual-purpose plant. Here are California are in agreement with the Kaiser- some of them: Catalytic study. — Have the regional natural water resour• ces been already fully exploited? — Are there no alternative water supplies Potential applicants for large plants near by? — Is the economic structure too rigid to Water costs quoted in these studies are very permit shifting of agricultural water to encouraging, compared with water costs industrial and municipal usage? for desalted sea-water prevailing some years — Is an integrated water grid available ? ago, but are still extremely high considering — Can the electricity network absorb the general prevailing water prices. output of a large base-load power- Future large size desalting plants of billions producing'unit? of cubic metres per year may develop to — Can a high value be allocated to the low single-purpose plants, owing to the enor• salinity of the product water? mous power blocks involved which few — Is there an adequate technical and ad• areas could absorb, but the forthcoming ministrative staff capable of coping generation of intermediate size plants in with advanced technology? the range of 100 million cubic metres per — Are there facilities for interseasonal year will certainly be dual-purpose power storage of large quantities of water? and water producing plants. The number of potential applicants for These plants will put to the test the scale- these intermediate size units under present desalting technology is certainly limited, especially those who could arrive at an economic and technical evaluation of the multi-purpose^use of product water.

Figure 10: Future trend of water costs from First plants—a stimulant for more conventional sources (in grey) and from the water conversion industry (in colour)— from Yet those first operating plants will become U.S. Dept. of the Interior Office of Saline a stimulant for those who prefer not to be Wíter, Í962 Report. first but will have to tap the sea soon for additional water supply. In turn, industry will join the present predominantly govern• mental research and development efforts and become a dominant factor in the pro• gress of desalination technology. It must be borne in mind that a few years of superi• ority may be decisive and that there is no better way of learning than by doing. Improved technology will lead to lower desalted water costs and this factor, com• bined with the reassessment of water "value" which is taking place, will make desalting plants more and more attractive as time goes on. However, the initial steps will have to be padded by an unconventional investment policy in large plants. This will prevent social and economic "friction". 1952 53 54 55 56 57 58 59 60 61 62 63 65 70 75 E U BU 5-11

is to destroy a large number of these micro- organ isms.

/ believe this is true of several other conser• vation methods. What advantages has irra• diation to offer over these methods? pilot plant The process I have been referring to is a kind of cold pasteurisation. It therefore offers the advantage over the traditional pasteurisation methods, which involve the use of heat to destroy the micro-organisms, that the properties characteristic of the fresh product are retained. This is of course not the whole story. A few weeks ago, work started Dr. De Zeeuw, what are the prospects of Although irradiation leads to the micro• on a food irradiation pilot plant conservation of food by 'irradiation? Are they biological stability of a product, it does a stone's throw away from the good enough to justify the construction of a not follow that complete storage stability Euratom ITAL Institute's labor• pilot plant? will be obtained. In order to arrive at this atories at Wageningen (Nether• result it may be necessary to destroy lands). Michel Gibb interviewed I think there can be no doubt that, generally certain enzymes, in which case irradiation Dr, De Zeeuw, Director of the speaking, they are good. But irradiation has to be combined with other methods, Institute. is not a panacea for all our food conservation or else the radiation dose must be consid• problems. The whole point of the pilot erably increased. plant is precisely to make it possible for However, this perfectionism is often not the marketing organisations to gain de• necessary. In many cases the elimination of tailed practical experience on how good the the most harmful groups of micro-organisms prospects of irradiation are for the conser• will stabilise the product sufficiently to vation of particular foodstuffs. extend its storage life by a few days. From a marketing point of view - I am thinking here of fruit and vegetables especially - Are there no useful research results available even such a short extension can be very In this connection? valuable.

The interaction between ionising radiation Can you give us a few practical examples? and living matter has been studied exten• sively for the past twenty years and the Irradiation of fruit, vegetables, fish and results of this work have clearly demonstra• meat offers the most obvious prospects ted that foodstuffs can be preserved by because these products have today a very irradiation. limited storage life. It should be added The problem is how to pass on to food that cold storage and disinfectants have not manufacturers the know-how acquired. always produced the desired results. Since It should be realised on the one hand that 1961 research work on fruit and vegetables it is not the rôle of a research institute to has been carried out by the Euratom/ provide industry with a ready-made process; ITAL Association in co-operation with the on the other hand the food manufacturing Institute for Research on Storage and Proces• sector is usually not able to try out on a sing of Horticultural Produce at Wageningen. commercial scale the results obtained in In the course of these investigations, use the laboratory. It is to bridge this gap that was made chiefly of low-penetration rays it has been decided to build a pilot plant. with the object of treating the surface of the fruit only. The reason for this is that How is it that irradiation improves the keeping the deterioration of such soft fruit as qualities of food-stuffs? strawberries, raspberries, cherries and plums is accelerated by the formation of moulds and yeasts on the surface of the It is primarily the action of micro-organisms fruit. Consequently a surface treatment is which causes all our food to deteriorate often sufficient. shortly after it has been harvested, gathered The results of more fundamental research or slaughtered. The effect of irradiation

73 on the influence of radiation on the physio• logy of the fruit have shown that the ripen• ing mechanism is also affected. Hence irradiation in this case succeeds not only in inactivating the micro-organisms already present but it has an effect on the natural decay of the fruit. These findings are particularly interesting: they open up the possibility of handling, marketing and distributing produce over longer periods of time than is now the practice. As can be seen from the plan, the food-irradiation pilot plant in Wageningen will be equipped I will give you just one other example, with two radiation sources. In one of the source-rooms will be housed a 85,000 curies cobalt-bO which shows up a different set of problems: source, and in the other a 3 MeV Van de Graaff electron-accelerator. the conservation of fish. The very low The cobalt-60 source is a dry source, equipped with a fully automatic multi-pass system for storage stability of fish is due to the natural exposing the material to be irradiated on four different planes. A loading and offloading conveyor microflora of the skin and in the intestines. will also be provided, capable of storing 8 hours of product. The speed control for the conveyor It consists mainly of organisms of the system will be infinitely variable. The Van de Graaff accelerator, which is a normal standard K Pseudomonas-Achromobacter group, which machine, will be vertically mounted. Products to be irradiated will be transported to and from develop rapidly at low temperatures. The the source on conveyors, adapted to the kind of product. storage of fish in ice therefore does not The working area is divided into two parts. The largest area is for those products which can be prevent decay. The maximum storage life handled at ambient temperature, while thesmaller room can be keptat a constant low temperature, of white fish is about 14 days at 0°C and at for handling products such as fish, meat etc. 4.4°C it is only 6 days. Next to the main entrance of the plant are situated the administration offices and a small labor• The most recent development in this field atory for dosimetry. is irradiation. It is possible to irradiate 1. Van de Graaff accelerator 3. Working area (ambient temperature) fresh fish in order to obtain astable product, 2. Cobalt-60 source 4. Working area (low temperature) but the sterilisation dose required leads to unacceptable changes in consistency, large amounts. This fact does not constitute other aspects such as the storage of the flavour and taste. On the other hand an objection to the use of radiation. It just irradiated products. It is also meant to irradiation combined with cold storage at means that before embarking on the large­ supply information on'production costs and relatively moderate temperatures (of the scale treatment of a particular product on the best ways of planning and running order of 0 to 4° C) offers good prospects. from a particular area, tests will have to a commercial facility. Finally sufficient As an illustration it may be stated that be carried out and, if necessary, adjustments amounts of irradiated food must be pro­ fillets of plaice wrapped in plastic can be be made to the treatment conditions. duced to make it possible to supply the stored at 4.4°C for at least 20 days after market and sound public opinion. i rradiation. To come back to the pilot plant: why did your choice fall on two types of radiation source, Who are the sponsors of the pilot plant ? / will ask you the inevitable question: is namely a γ­emitting isotope and an electron­ there any possibility that irradiated food emitting machine, instead of only a y­source There are several sponsors. It has been could be a threat to health? as is generally done ? proposed that a quarter of the investment cost be borne by the Common Market's Considerable research efforts have been Our institute has always had a keen interest European Agricultural Guidance and Guar­ devoted to this problem. It is accepted in the possibilities offered by an electron antee Fund. The remainder of the cost will today that ¡rradiation is safe for most food­ acceleratorfor both shallow and penetrating be shared by the Dutch Government and stuffs: no toxins, no carcinogenic elements, treatment. When such a machine is used in the Dutch marketing organisations. no induced radioactivity are produced. a straightforward manner it produces elec­ However irradiation can entail a shift trons, which have a low penetration. On And who will actually run iti in the microbiological balance: the most the other hand, if agold target, for instance, resistant micro­organisms stay alive and can, is placed in the path of the electron beam, The plant will be run by a board of gover­ because of the absence of competition, high­penetration electromagnetic radiation nors, all of whom will be representatives develop into larger colonies than would (Bremsstrahlung) ¡s produced. of the marketing organisations. I think this otherwise have been the case; if some of In an electron accelerator it is possible to is a unique feature. The Wageningen food these micro­organisms happen to produce vary both the energy of the emitted irradiation pilot plant cannot be said to be toxins, then a threat to health exists, be­ particles and the density of the beam, which entirely unique from the technical point of cause they will be produced in abnormally makes for great flexibility. Moreover the view: similar plants are being planned or machine can be, unlike a γ­source, switched under construction in other countries and on and off, so that no radiation energy is a few are already operating. But as a rule lost when it is not being used. commercial organisations, although they However, it was decided to instai a high have a voice on the governing boards of penetration γ­source as well, in order to these plants, do not bear complete respon­ make more complete the experience which sibility, as their counterparts will do in could be derived from the pilot plant. In any Wageningen. case this arrangement has additional ad­ The marketing organisations will of course vantages: two different treatments can be not be left altogether to their own devices. given at the same time and furthermore the Two representatives from the Dutch Min­ flexibility of the whole is increased. istry of Agriculture and two representa­ tives from the Euratom/ITAL Association will What capacity will the plant havei be appointed to assist the board of gover­ nors. It will be capable of treating 1000 kg per The board will also be assisted by an ad­ hour. visory committee whose members will in­ clude public health experts, representatives Is this not a fairly high output for what is of the Press, housewives, etc. after all only a pilot plant ? Vou explained earlier how the investment costs Not if you consider that it is meant to be would be covered. What about the running the immediate precursor of future com­ costs Ì mercial facilities. If information had been wanted only on such parameters as dose­ Basically it will be up to the board of rate, required radiation dose, etc., then it governors to conclude contracts with is true that a plant with a capacity of some firms who wish to avail themselves of the 200 kg/hr would have been adequate. pilot plant's facilities. Tailor­made experi­ But the purpose of this pilot plant goes mental programmes can then be drawn up, further. It is meant to provide technical the results of which will be the firms' data on the actual processing and on various property.

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if the invention is kept secret, the inventor cannot make any public claim to merit and often finds difficulty in turning it to profit. ■ ■ ■ i In former days the only way an inventor could defend himself against imitators and competitors was by jealously guarding the Euratom and patents secrets of his craft. This system had very serious disadvantages: in the first place it was unreliable (the simple explanation of the dispute overthe invention of printing, JACQUES RENAUDIE, Head of Patents Bureau, Directorate General for Dissemination for example, is probably that one of Coster's _ «n«v""l0>> of Information, Euratom. ,, w­....,'" former workmen was taken on at Guten­ "Ό,. berg's works); secondly, it slowed down or prevented those exchanges of knowledge which are the yeast of technical progress; m and lastly, there was always the danger that the use of some invention might be lost Somewhat paradoxically, it is nowhere laid to mankind for ever (for instance, no one down in the Euratom Treaty that the Eu­ has ever succeeded in reproducing certain ropean Atomic Energy Community must pigments used in the stained­glass windows patent the fruits of its research, and yet it of the Middle Ages). does so; by 1 August 1966 a total of 2201 Not everything is patentable, however. The patent applications had been filed in Eura­ legal criteria vary from country to country, tom's name and 1214 in the name of but two of them are universal—the inven­ parties associated with or under contract £K^ tion must be new (though there are limits -""*Ì **S* iiniiiiw "■' to Euratom, covering 812 inventions in of space or time to this "novelty" condition -"*Paris in 1883, to which more than 70 countries acceded and ensure the dissemination of technical (including the USSR in 1965), anyone who knowledge". It is obvious, however, that files a patent application in one of the unless certain safeguards accompany this ptruiu.i­y.'i: FRANÇAISE countries of the Union is allowed one year dissemination any third party will be able to DE HmtBHUE £T CO COKMERCE BREVET D INVENTION to effect the "corresponding applications" make free use of the discoveries made in SERVICE Τΐ· 971.384 <1. U PHQPRIETL INDUSTRIELLE i n other Union countries, claiming the date the course of research financed by the of the first application as priority. After that Community budget. But Article 1 of the time he forfeits this advantage; as the Treaty specifies that "it shall be the aim of effective date of filing in a particular coun­ the Community to contribute to the raising Délivré le 12 juillet 1950. — Publié le 16 janvier 1951. try is the only one legally recognised, he of the standard of living in Member States (Brevet d'invention doni la délivrance a été ajournée en exécution de l'article 11, (■ 7, then runs a considerably higher risk that and to the development of commercial ' de la loi du S juillet 1844 modifiée par la loi du 7 avril 1902.) On sait que l'irradiation de l'uranium par des 1 Et un enrirlimement plus élevé en isotope someone else will get in first with his exchanges with other countries by the neutroni provoque une rupture nucléaire de 235 (par exemple doni la proportion de 5 il 1 l'uranium, avec dégagement de quantités con­ ou de 10 à I) dunnera des résultais enrure plus invention, if only because of his initial creation of conditions necessary for the sidérables d'énergie. Cette rupture donne lieu ­a l'émission de neutrons secondaires, parmi les­ .Au cours de la marche du dispositif cl ou fur patent application if it has been published quels un certain nombre peuvent provoquer á et ;'. mesure que se développent les chaînes de speedy establishment and growth of nuclear leur tour de nouvelle» ruptures, et une réaction, réactions, l'isotope 235 est consonimi', sa pro­ à chaîne explosive peut ainsi prendre naissance portion tombe, ce qui amènerait Ici conditili DI in the meantime. industries". et se propager au sein de la masse uranifere. β redevenir moins favorables. Mais en meine temps Divcrj moyens ont été proposés pour permet­ la masse uranifere s'enrichît en Isotope 239 We should note here that each patent is The ownership of a patents portfolio serves tre l'extraction et l'utilisation à des lins indus­ (qui se forme û partir de l'isotope 238) et cet trielles de l'énergie développée por res chaînes isotope 239 peut vraisemblablement remplir therefore valid in one country only, with precisely that aim, in that it helps the Com­ fle rupture successives, et notamment, l'on α un rote analogue à l'isotope 235 cl compenser déjà eu l'idée de réduire la vitesse de tout ou par suite, du moins en partie, l'appauvrissement partie des neutrons secondaires (de manière graduel de la masse en isotope 235. one exception—the African and Malagasy munity to give preference to the industries qu'ils deviennent les neutrons lents approxi­ Dans la présente invention, l'uranium peut mativement en équilibre thermique avec le mi­ être sous forme d'uranium nié lall i qui', dc com­ Office for the Protection of Industrial of Member States and strengthens its hand lieu) en introduisant ou sein de la masse urani­ posé d'uranium ou de mélange contenant de fere un on dei éléments de ralentissement (hy­ l'uranium. Property grants a patent which is valid in in exchange agreements with other coun­ drogène, eau, etc.) Les dispositions de la présente Invention Or on s'est rendu compie, conformément å la peuvent être eombmies avec celles faisant l'ob­ the twelve member countries of the African tries. présente Invention, que le développement dei jet de la demande de brevet francais du l"mal cnatnej de rupture! *l par suite le dégagement 1939 pour »Dispositif de production d'éner­ and Malagasy Union. There are, moreover, Furthermore, since Article 12 of the Treaty d'énergie qui en résulte κ trouvaient favorisés gie * et/ou de la demande de brevet français du si l'on opérait avec une masse d'uranium com­ 2 mai 1039 pour »Procédé de stabilisation several very advanced international patent portant une proportion d'isotope 23 5 plus élevée d'un disposili! producteur d'energici. regulates the use of "patents, provisionally que n'en contient l'uranium naturel. schemes ("European patents", for the six On sait que (si l'on fait abstraction de l'iso­ Perfectionnement aux dispositifs Je production protected patent rights, utility models or tope 234 extrêmement rare) l'uranium naturel d'énergie utilisant les réactions nucléaires de Common Market countries, "Nordic pa­ est un mélange de deux isotopes : l'isotope 238 milieux uranilcres; ce perfectionnement consis­ patent applications, which are the property et l'isotope 235 (dam la proportion d'environ tant à enrichir la masse d'uranium 'en isotope 99,3% d'isotope 238 pour 0,7% d'isotope 235; cet enrichissement pouvant être dant la tents" for the Scandinavian countries), and of the Community", their existence is 235). proportion de 1, 2 á 1 et plus, et pouvant s'ef­ En réalisant, par diffusion thermique ou par fectuer par diffusion thermique ou par tout this tendency to i nternationalise the patents officially, though indirectly, recognised. tout autre procédé connu, un enrichissement de autre moyen. l'uranium en isotope 235 dans la proportion de Huis IfEunic« vo* ΠΛΙ.ΒΑΝ", system is spreading. It has reached the In its main task of promoting research, the I, 2 à 1, on réalise déjà des conditions plus fa­ Jtis­KntDCïic JOLIOÏ et I.ivr KQWARSKL vorables au développement dea chaînes de rup­ United States, witness the speech delivered Commission has two means of action—the tures. ι, Bu >, Lit by Mr. Edward J. Brenner, Commissioner Prix du fascicule : 25 franca. Joint Research Centre establishments and Pour li rate da fuciniti, i'iditucr 1 l'Urtativi .N'ITIOSILT, ;;, ιυ­ de U Contestou, Pul* (IS') of Patents, on the occasion of the 175th contracts or association agreements con­ anniversary of the United States patents cluded with enterprises in the Community. legislation. Mr. Brenner acknowledged the In either case the studies are financed by advantages of extensive co­operation by all public funds provided by the Member countries in the "preliminary examination" States; It is therefore normal that the first soas to avoid unnecessary repetition of the fruits of Community research should go to to grant sub­licences under certain con­ "searchesfor prior publication and use". those States and their industries (or their ditions. Another important point is that the law citizens). We come now to the key question—the in all countries deals very sternly with Such priority may take two practical forms. "profitability" of patents. Without going infringers—those who use a patented According to whether the information is so far as to write, as someone did, that it is invention without the consent of the patentable or not, it is issued either (Article "easier to turn money into patents than patentee. 12 of Treaty) under a preferential licence patents into money'*, it must be admitted Lastly, we should mention that as well as system, which was defined in a statement that it is far easier to calculate the amount of being exploited by its owner, an invention by the Commission to the Council of expenditure incurred for patents than the protected by a patent can either be "as­ Ministers, or (Article 13) by restricted amount of profits they bring in. It is a fact signed" (sold) or leased under a "licence" dissemination, confined to persons and that the profit reaped from a patent cannot which may be gratuitous or subject to enterprises in the Community. always be reckoned in figures, and the various fees, the best­known of which are Again, it was in the light of these basic receipt of royalties for licences is only one the dues'called "royalties". principles that the Commission decided of the possible benefits. who was to own the patents. Obviously, To borrow an analogy from real estate, for inventions produced by the Joint Re­ we might ask if the rational way of using a Why does Euratom take out patents? search Centre, the Community applies for house is to occupy it, let it, . . . or sell it! them in its own name; but for inventions In the last two cases the profit is readily Let us examine the reasons that prompted issuing from contracts or association agree­ apparent in the sale price or the rent the Euratom Commission to apply for ments, this right belongs in the first place received. less expenses; but in the case of owner occupation, can a price be put on patents. to the contractor or associate of the Com­ the direct advantage thus obtained (security Article 2 of the Treaty of Rome says that munity, subject to his allowing the latter a of tenure, stability of charges, planning of the Community must "develop research free and irrevocable licence with the right

77 May 17, 1955 E. FERMI ET AL 2,708,656 NEUTRONIC REACTOR Filed Dec 19, 1944 27 Sheets-Sheet 20

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Extracts from the patent granted to Enrico Fermi and Leo Szilard for the -^S&éU+frÂ* 'neutronic reactor'. The application was filed on 19 December 1944. maintenance and improvements) ... or the How is a patent application filed? author, read it in the Euratom Bulletin, higher credit status of the owner, should No. 4/64, p.3). he wish to obtain credit? The only items The foregoing is enough to suggest that the In practice, it is often difficult to decide that can be expressed in figures are the problems of industrial property rights are whether to patent an invention and, if so, maintenance expenses and the market value often complex; lying midway between the in which countries to file corresponding of the house, which varies. It remains to be law and applied science, they have to be patent applications. The happy medium shown that patents are necessary in the dealt with by engineers with a good know• must be struck each time, by good judge• same way as a house. One could, conceiv• ledge of the law and lawyers acquainted ment, for it cannot be calculated, between ably, run an enterprise without resorting with the technical difficulties. The Euratom expenses of filing, which are known to the protection of industrial property Directorate for Industrial Property Rights, precisely in advance, and the potential rights, in the same way as nomads do not like the patent agents' offices or the patent advantages, which can only be estimated. worry about buying or renting a piece of departments in large firms, has a number The estimate, likethe navigator's reckoning, land. Obviously, however, the industrialist of these "rare birds", carefully proportioned must be compared afterwards with the who does this would be exposing himself as to the various branches (chemistry, facts so as to ascertain the error, analyse it to serious hazards; if he does not patent electronics, mechanics etc.) and the five and reduce it the next time. Unfortunately the processes and devices which he has languages needed ( the four official Commu• this empirical method is ill suited where developed and utilises, a competitor may nity languages and English). there are rapidly-developing techniques, very well do so in his place . . . and then The engineers in the Patents Office study fledgling markets and bodies which have claim royalties from him or even sue him all the scientific reports drawn up either by only been in existence for a few years, as for infringement. the Joint Research Centre or by Euratom's in the nuclear field. When we realise the constant watch kept contracting or associated partners, before Faced with these difficulties, one must by many firms on the patents granted to they are published, in order to detect any "cast one's mind into the future and thus their rivals, and all the tricks used to baffle patentable information (by 1 August 1966 bring into play a certain degree of fore• them, we see the "aggressive" rôle patents a total of 7097 reports and articles had sight, of prophetic instinct, and also a may play in the world of business. The been "screened" in this way). Each patent certain shrewdness"'. Belgian Patent Office furnishes an excellent application demands a clear text (legal example of this, for Belgium usually grants requirement), filing formalities that differ patents six months after the date of filing; from country to country (and the many By way of conclusion .. . hence one American firm can keep watch on inventors who have had to travel scores another in Brussels, as the Belgian patent of miles to swear before a consul that they In every hive - that model of organisation will be published long before the American. were indeed the inventors know something in nature - there are guardian bees who As to the counter-ruses adopted, one, for about this), examinations by the national safeguard the ownership of the honey made instance, consists in patenting a number of Offices which go on for years, and so forth. by the thousands of workers; biologically products simultaneously, only one of which similar to the workers, the guardians may is the article which the firm is preparing It has been frequently said and written that seem to be vexatious and unnecessary, to launch on the market. there are no real inventions any more, only but it is they who keep thieves away from improvements; certainly the modern inven• the laboriously gathered heritage. Until It is impossible to tell whether a new tor does start from very broad technical the day the beekeeper comes . . . partner, before sitting down at the nego• and scientific foundations which constitute tiating table, has already attempted - and at what is called the state of the art. In new what cost - to get round a patent whose fields, however, such as that of nuclear value you tended to underestimate. You energy some years ago or space research never know, either, what indirect benefit today, this statement is not quite true. you may have reaped from an exclusive As Dr. J.M. Hill, member of the United exploiting right, were it only temporary. Kingdom Atomic Energy Authority, said That is why it is wiser to speak of the at the Foratom Congress at Frankfurt efficiency of patents as one speaks of the "In the early days of nuclear energy, every (offensive) efficiency of an advertisement time two or three physicists went out for or the (defensive) efficiency of a lock a drink together they invented a new without being able to calculate this exactly.. reactor". except by statistics effected after the Many new reactors have been invented . . . event. and others will certainly follow. They must, The fact that the Soviet Union has come if nuclear science is to go forward, even round to the patents system, after years though apparently promising prototypes of regarding it as one of the evil results have been abandoned. How many of us of capitalism, proves that it is valuable remember, in another context, that the even in economies of widely differing first automobile to reach a speed of 60 mph I. A. Bertin, "Le secret en matière d'invention", structure. was electric? (Possibly those who, like the Editions du Tambourinaire, Paris.

79 EUBU 5-1

ed in. And how is he to find his way around in this welter of detail, how distinguish the right from the wrongor the out-of-date, what system shall he adopt in his quest through the various atlases of nuclear data? Low-energy nuclear physics What the engineer needs is a clear picture of nuclear physics as a whole, that is, he needs to know the fundamental rules gov• erning nuclear properties so that he can and the development of build up a correct mental framework within which he can move around without effort. But at the moment there is no such thing nuclear applications as an unequivocal and complete picture of nuclear physics, such as we have of electro- magnetism for example; the laws govern• PROFESSOR UGO FACCHINI, Centro Informazioni Studi Esperienze (CISE), Milan. ing nuclear forces are still far from clear, so that we have no firm foundation on which to build up a system of nuclear physics in the same way as the science of electro- ^^^ - magnetism is based on Maxwell's laws. The physicists themselves are still studying the From the time when Rutherford triggered atomic nuclei, exploring individual details off the first nuclear reactions on light and seeking new nuclear reactions. nuclei down to the present day, all the From all these experimental data it is hoped known nuclei have been bombarded and to evolve a theoretical description of disintegrated in all manner of ways and nuclear properties. For this purpose the thousands of nuclear reactions of physicists generally resort to various models various types induced have been studied of the nucleus, each of which brings out from every possible angle. Even so, many some particular aspect of nuclear phenom• problems remain unsolved and, as far as ena. applications are concerned, the demand for Thus we have the liquid drop model, which nuclear information is continually growing is self-explanatory, thegas and the shell mod• — in the nuclear engineering and applied els which, on the other hand, demonstrate physics laboratories, which are increasingly the fact that the movements of the many engaged in the design of new types of nucléons contained in the nucleus are reactor, in the laboratories attached to practically independent; the optical model, nuclear power-plants, in thermonuclear used to describe the property which the fusion laboratories, and also in the radio• nuclei have of diffracting nucléons, and the activity monitoring centres and in all the statistical model, used to describe the various fields of application of radio• thermodynamic properties of the nuclei. activity and radiation in industry, medicine These models are highly useful tools for and agriculture. The development, especial• expanding the frontiers of knowledge ly, of fast reactor and thermonuclear in the sub-atomic world. fusion studies indicates that in Europe and In recent years we have begun to grasp a the Euratom countries, as elsewhere, the number of facts and shed light on the next few years will bring a wide and growing energy-level properties of nuclei, on market for such information. nuclear forces and on the mechanism of nuclear reactions. Nuclear reactions galore! Let us briefly consider the line of enquiry which the nuclear physicists are at present But if an engineer looks for some item of pursuing. nuclear information, what does he find? A list ad infinitum of the most widely Reactions on light nuclei assorted nuclear reactions, obtained with General vieuw of the CISE Nuclear Labora• various particles and energies, and often Thestudyof the reactions produced by deu- tories, Milan, with Van de Graaff tower in missing out the very data he wants and terons, protons, alpha particles and gamma background. skating over the very problem he is interest• quanta on deuterium, lithium, etc., and on very light nuclides in general, is aimed at so­called magic numbers of protons or providing simple direct data on the nuclear neutrons—are indeed spherical. Others, forces acting among small numbers of the intermediate nuclei, generally consist Fig. 1: The cc partiele consists of two nucléons and at revealing the structure of of a spherical kernel surrounded by a protons and two neutrons. the light nuclei. more or less ellipsoidal cloud of nucléons We still know little about nuclear forces; (Fig­ 2). it is clear that there are repulsive Coulomb Nuclei are similar to all microscopic sys­ forces between protons and far stronger tems, atoms, crystal lattices, etc., in that attractive nuclear forces acting over a short the energy that can be imparted to them H« range, i.e. at distances of the order of one can only have certain well­defined quantic nucleus diameter, between all the nucléons ­ values, the sum total of which constitutes neutrons and protons. At yet shorter the nuclear energy levels. distances the nuclear forces likewise become Spectroscopic analysis of the first energy repulsive and this is what prevents the levels of nuclei has proved particularly "collapse" of the nucléons in the nucleus. rewarding. In the case of spherical nuclei Not much more is known about the nuclear the first levels correspond to the excitation Structures composed of cc particles forces, and the current meson theories of one or a few of the nucléons contained are found in some light nuclei; e.g. I ¡able to explain their origins and properties in the surface of the nucleus, whereas in "Be consists of two a particles are still by no means clear or complete. the deformed nuclei levels are observed Nevertheless, study of nuclear reactions which denote movements of the whole and the radiations emitted by light nuclei nuclear cloud—vibrations and rotations has made it possible in recent years to with definite rules and strong analogies Be outline a new structural theory on these with the properties of molecular move­ nuclei, from which it appears that they ments (Fig. 3). are composed of agglomerations of alpha At higher energies (over 5­6 MeV) the (X) particles, deuterons and single nucléons nuclear levels become extremely numer­ (Fig.1). and 12C of three a particles; ous. This multiplicity is explained by Reactions with light nuclei are also of great assuming that many nucléons are excited interest from the standpoint of fusion individually and carried into higher energy physics and the harnessing of fusion for orbits in various combinations. The reso­ power generation; for, as is generally nances produced by thermal neutrons can known, typical fusion reactions are those be assigned to this level. 12. which produce the synthesis of two deute­ At excitation energies of 12­18 MeV there rons or of one deuteron and one nucleus are also particular levels which represent of tritium, and in the sun, for instance, well­defined modes of vibration of the nu­ nuclear energy is produced by a series of clear kernel; in these motions the whole of reactions involving a well­defined group of the neutrons and protons enter into a I ight nuclei. kind of reciprocal vibration. These motions are studied more particularly by means of in certain excited states it appears Nuclear shapes and motions the reactions induced by gamma rays. that the three α particles can adopt a linear arrangement. Information as to the shape of the nuclei Mechanism of nuclear reactions can be derived from detailed analysis of the properties of certain typical nuclear At the present time nuclear reactions are reactions; among the most important of the only means available to us for penetrating these are Coulomb excitation, in which a the mysteries of the nuclear world. Gener­ proton or alpha particle passing close to a ally speaking, we have in the nuclear reac­ nucleus transmits a definite quantity of tion a particle (proton, neutron, alpha energy to it by Coulomb effect, and the re­ particle) colliding with the nucleus, as a '•Li, on the other hand, consists of one actions induced by 10­100 MeV gamma­rays. result of which the nucleus breaks up, a particle and one deuteron. Some of the shape properties of various emitting one or more nuclear particles. nuclei can also be deduced by study of Although the process of interaction be­ their beta and gamma emission. tween incident particles and nucleus in­ We know nowadays that nuclei are not volves many of the nucléons contained Li just little spheres of nuclear matter but in the nucleus, the entry of the particle differ in shape and structure and vary in is governed by simple laws. In the case of complexity. charged particles, their penetration into Certain of them—the nuclides with the the nucleus is determined by Gamow's

81 repulsive Coulomb potentials; as to neu• "evaporation", is studied on the statistical Towards a systematic picture trons, the optical models developed by model, which uses the traditional ther• Weisskopf and co-workers describe the modynamics methods; it can be used to As we have seen, the study of these en• nucleus as having appropriate wells of calculate the probabilities of emission of thralling problems aims at building up a attractive potential (Fig. 4). the different particles, their energy dis• logical overall picture of the nuclear prop• After the incident particles have penetrated tribution and their angular distribution erties, and there are still many gaps to be the surface of the nucleus, either of two (Fig. 5). filled in. We should note, however, that types of reaction may occur. every subject examined by nuclear phys• One is the direct reaction, in which the Fission icists is also of immediate practical interest, incident particles collide with a surface in that it illustrates a technique of manip• particle of the nucleus. In the brief time Although our acquaintance with fission ulating nuclei. Every study of nuclear 22 of about 10- seconds either the particle phenomena is of so many years' standing, reactions or nuclear radiations emitted by struck or the incident particle may be there are still considerable gaps in our nuclei goes to swell the great atlas of emitted as a result of the impact. experimental knowledge and a complete nuclear data being compiled by physicists. The direct reactions have been known for theoretical model describing these pro• This collection is the source of the nuclear a decade or more, yet their properties, cesses remains to be devised. data used in the various applications for instance their collision cross-sections Even now a set of the basic properties of nuclear energy, radiations and radio• at various energies and with various nuclei, governing the fission process is still ex• isotopes. remain largely undetermined and there is plained by Bohr's original theory, which Even from this angle, however, our know• not even an overall classification of these assumes the fissile nucleus to have the ledge is far from satisfactory. Although in reactions. properties of a liquid drop of nuclear matter the field of slow neutrons, for instance, In the majority of cases, however, the and studies its deformations and break• everything measurable has probably already reaction is not direct; the incident particle up into two fragments. Bohr showed in been measured, when we turn to the becomes completely embedded in the particular that, before splitting, the nucleus reactions Induced by fast neutrons and nucleus, within which its energy is dissi• assumes peculiarly elongated forms, known other particles the unexplored zones are pated in the form of heat. as "saddle states". These forms represent far more extensive than the charted areas; At this point it is legitimate to introduce an unstable condition beyond which the for, by reason of the multiplicity of utili• certain concepts of thermodynamics such nucleus divides into two parts (Fig. 6). sable particles, their energies, and the as nuclear temperature, entropy, etc. So far, however, the liquid drop nuclear many nuclides, the number of nuclear After a time which is, on the nuclear scale, models have not shown the way to a reactions possible is immense. Further• relatively long (10-18 to 10-12 seconds) detailed description of the various modes more, it must be remembered that the the nucleus "evaporates" one or more of fragmentation of the fissile nucleus study of emitted particles involves measure• nucléons or an alpha particle and cools - mass of the fragments, their kinetic ments of energy, angular distribution, down to its fundamental state. energy, and the energy of excitation and angular correlations, and gamma ray This immediate particle emission, or subsequent evaporation of the neutrons. analysis.

Fig. 2: Some nuclei have a spherical kernel structure. These are the "magic" In the intermediate nuclei the spherical magic kernel is surrounded nuclei, i.e. those with 2, 8, 20, 28, 50, 82 or 126 protons or neutrons. by a cloud of outer nucléons which generally assumes an ellipsoidal shape.

-Q

lutetium thorium

2 8 20 28 50 70 82 126 184 N

82 number of neutrons Fig. 3: In the spherical nuclei, in the first excited levels, one or several nucléons leave their orbits and rotate in excited orbits.

In the ellipsoidal nuclei, however, the first energy levels correspond to overall motions of the cloud of outer nucléons: 45 MeV cyclotron constructed by G. Tagliaferri, C. Succi and co-workers at the University of Milan' vibrations,

Obviously at this point the classification cases he has to utilise the basic concepts of all possible reactions and their analysis and, in particular, the models, developed is so huge a task that the enormous labour by physicists, and in this field close collab• or rotations of collection and sifting of such data will oration between engineer and physicist go on for years to come. This mass of work is particularly vital. ought to be tackled by special centres set up on the lines of the Bureau of Standards, which would carry out a systematic and Measuring techniques detailed analysis of each reaction. But the continual evolution of techniques and Another valuable contribution by nuclear axis of rotation spii analysis methods, the growing interest physics to technological advance is the shown by engineers in information liable to parallel development of nuclear measuring further the progress of reactor technology, techniques. and above all the desire of physicists to The search for new ways of studying nuclei pin-point as yet unexplored details through has in late years given rise to new methods these individual reactions or to gain a brief of particle detection, to more accurate insight into the properties of nuclear analysis of their properties, and to more structures, are such that this broadening powerful devices for generating particle of our knowledge, however disorganised beams with determined properties. and repetitious it may often appear, is Beside the old Cockeroft-Walton generator nevertheless a vigorous and exciting now stand the tandem Van de Graaff, process, whereas standardisation and clas• cyclotrons and linear accelerators In a sification are a much slower affair. steadily evolving line. It is often important to the nuclear engineer In the field of detectors we have added to to be able to predict the properties of the old Geiger-Müller counters and ionisa• nuclear reactions even where no direct tion chambers crystal scintillators and the measurement data are available. In such silicon and germanium detectors which

83 Fig. 5: In direct reactions a collision occurs between the incident particle and one of β the nucléons of the nucleus.

Fig. 4: The interaction between a particle In "evaporative" reactions the whole nu­ and a nucleus can be described by means of clear surface is heated and the excited a nuclear potential: in the case of a charged nucleus then "evaporates" one or more particle (proton or α particle) the potential Q' nucléons. consists of a repulsive component and a well of attractive potential due to the nuclear forces. Φ

In the case of neutrons only the attractive well is present.

today enable us to determine the energy of ionising particles to within a few ppm and with almost 100% efficiency, as well as time­of­flight spectrometers for fast Fig. 6: Fission states: in its fundamental state the uranium nucleus has the usual ellipsoidal neutron measurements, which are capable shape; when excited by a neutron it assumes the "saddle state" form and then splits into two of determining time intervals of the order hot fragments. The curve shows the evolution of the total energy of the nucleus for increasing of 1/10,000,000,000 sec. deformations. All these techniques, devised mainly in the nuclear research laboratories, today form part of the basic equipment of nuclear saddle point measurement centres, radiochemical cen­ tres, reactor control rooms, nuclear materials testing laboratories, health physics laboratories and, generally speak­ ing, wherever radiations or radioisotopes are used. evaporated neutrons Another function of the nuclear physics laboratories is to train in the use of these O O o techniques physicists who will be able to go and put their knowledge into practice in the applied research laboratories. In Vi / general, the two­way exchange which takes place between the groups pursuing fun­ damental research and those engaged in nuclear engineering continues to be most fissile nucleus in saddle state fission fragments valuable. fundamental state

84 EUBU5-14

of the total damage being a fraction of the per cent better or worse than the predic• tions based on the previous year's figures. If an insurer has to make out a million third- party car insurance policies he can be sure that the compensation-rate to his clients Nuclear energy will jibe roughly with the statistics; but this is by no means the case if he has only ten risks to insure. Bad luck might then have it that in spite of (let us say) a 1% compensation-probability on the ten risks, insurance he might have to pay five times that amount. In order to hedge against this eventuality, when the number of insurants is small he HANS-DIETER MOSTHAF, Directorate for Economy, Euratom will have recourse to reinsurance. Insurance companies are linked together within a worldwide reinsurance network, which guarantees the permanent spreading of risks. There are still people who imagine nuclear energy. Of course, nowadays we all know energy to be a physicists' preserve. But in that nuclear energy in the bomb and nuclear order to progress from atom-splitting to energy in the power plant are two quite A speculative business? nuclear power plants, physicists had to different kettles of fish, but a certain diffi• enlist the help of technical specialists of all dence in the face of this new hazard none• To return to nuclear ¡nsurance; at the kinds and men of many other professions, theless persists. moment there are not more than one hun• such as businessmen and lawyers. One In addition to this psychological factor there dred nuclear plants in the whole world, example of the need for this co-operation are solid business reasons for this attitude: including nuclear power plants, research is nuclear risk insurance. If nuclear power we know that a nuclear power plant cannot centres with their reactors and laboratories, plants are to be built, there must be a explode like a bomb, but has anyone yet plants for the processing of irradiated nu• means of insuring the risks which they seen what does happen in the event of a clear fuels, storage facilities and so on. entail. major accident in peaceful nuclear energy There are thus at most one hundred poten• In the early stages of nuclear energy pro• production ? The answer is no. tial nuclear insurance risks. We say poten• duction, ten years ago, insurance companies tial, because many of these risks are not were not at all prepared to provide cover Insured—e.g., most research centres and against nuclear hazards, yet this cover was The unknown nuclear risk also many power plants under public vital. The authors of the Euratom Treaty ownership—since the owners feel capable therefore saw one of the tasks of the Euro• How are the insurers to assess this unknown of bearing the consequences of any damage pean Atomic Energy Community as being nuclear risk? Nuclear plants are built in themselves. "to facilitate the conclusion of insurance such a way that no nuclear damage can It is clear that with so few plants ¡t is not contracts" (Article 98).' occur—at least that's what the engineers possible to spread the risk. The situation Why is this still so difficult? Have we not for say. But this is an elementary principle of would not be so difficult if one could rely over a century had in Europe a flourishing aircraft construction, dam building and upon there being a large number of in• insurance business, able and willing for its railway engineering. The probability of a stances of small-scale damage. But the own profit motives to insure risks? major nuclear accident is doubtless very opposite is true: the damage probability ¡s Unfortunately this does not apply to nuclear small, but it is not zero, otherwise no one extremely low, but the possibility of very i nsurance. would be trying to insure against it. large damage is still not completely ruled The first obstacle was a psychological one: It might be thought that the Insurers ought out. An Insurer—even if he takes the we all made our first acquaintance with to welcome this new business, which brings lion's share of ten nuclear risks out of the nuclear energy through the atom-bomb. It in premiums and barring accidents costs small number on the market—can still not is not surprising that insurers, like the rest them nothing. But the insurer's reply is achieve a judicious statistical spread of the of us, wanted to steer clear of nuclear that he has to be prepared for large-scale risk. damage any day. If this should occur, where As we have seen above, this would not in does he get the money to meet the claims? itself be too serious, in view of reinsurance. I. The Euratom Commission has held colloquia with In traditional branches of insurance he But it can easily be seen that this again is the nuclear insurers and insurants to discuss the major problems. The first was held in Wiesbaden in draws on the premiums contributed by the not possible here, as there are too few 1961, the second in Florence in 1962, the third in many other insurants in the same field for Aix-en-Provence in 1964 and the fourth in Berlin in nuclear risks in the whole world for it 1965. The proceedings of the last three colloquia have whom it was no-claim year. The business to be possibletoachleveanoverallstatistlcal been published by the Euratom Commission under risk then consists merely in the possibility numbers EUR 486, EUR 2464 and EUR 2642. spread by reinsurance. 85 Nuclear insurance is thus a veritable specu• These are all commercial motivations. We which an individual insurance company is lation for the ¡nsurance companies; and will not conceal, however, that ¡nsurance willing to provide will only be a very they do not consider such speculative risks circles also felt a general responsibility not small fraction of the total. to be within their province. to shirk this national economic task, and In order to remedy this situation, the to find a way of meeting the demands made insurers joined forces to form pools, as had It was therefore impossible at first to find on them. already been done elsewhere, e.g. in air- any insurance cover. But wherever nuclear travel insurance. This happened first in the plants are to be built and operated by USA and then also in Europe (In all Com• private owners it is a matter of urgency to Why insurance pools? munity countries except Luxembourg). All provide insurance coverage—indeed this is ¡nsurance companies in the country in a precondition for the industry's develop• The ¡nsurance business has therefore stated question which wanted to get in on nuclear ment. If private insurance had declined to its readiness to cover nuclear risks. But insurance joined their national pool and meet the need, to cover this risk the state what could it do to circumvent the dangers quoted the cover which they were willing would certainly have found a way, either inherent in its inability to spread the to contribute for each individual risk. But through government guarantees or by hazard? The insurers decided that if they even the total cover which a national pool some other means such as a public and declared themselves ready to take on was able to build up from the contributions fiscal arrangement—as has in part already nuclear risks and thereby embark upon of its members was far from adequate to happened. But the insurance business felt speculative enterprises, they could do so provide for meeting the potential claims. it must play its rôle within the national only up to very low ceilings. Some big In so far as the capacity of the pool in economy. It would be safe to assume that ¡nsurance companies were thus ready to question is inadequate, the pools of other Insurers would be very reluctant to see chip in to the tune of half-a-million units of countries join in as reinsurers. Even then the state muscle in on their territory and account2, for example, others with 50,000 it is not certain that in every instance the take over a field which they themselves or as little as 10,000 u.a. But the nuclear sum will be sufficient fully to cover the had appeared to spurn. This might lead to power plants being built today are worth value of the plant. state intervention in other insurance fields 60 to 150 million u.a. If the material value A great number of obstacles remain. Let us too. Furthermore, the insurers perceived of such a plant is to be insured, the cover take for example the lack of competition. that nuclear business would be bound to When all the insurers in the world have to boom in the course of time. 2. I unit of account = I US dollar. join together in covering a risk, all competi-

86 tion is ruled out.3 The insurers have agreed take-it-or-leave-it situation will be possible three-quarters of the risk for large nuclear that direct ¡nsurance coverage be limited only when the ¡nsurance companies make plants. strictly to the pool of the country in which larger capacities available for nuclear in• the insurant plant is situated, the other surance. Despite the undeniable risk which Insure all plants pools being associated solely as reinsurers expansion of capacities entail for the in• with a risk in a country other than their surer in view of the far too limited number Another Euratom initiative is aimed at the own. In fact the total exclusion of all com• of policies, a not inconsiderable increase insurants, who are urged wherever possible petition is brought out particularly clearly has in fact occurred in the course of the to take out insurance for their plants. The by this system, under which all the nuclear years. This is much to be commended. But uninsured plants are mainly those owned insurers have to share in every big risk it is quite insufficient even to make com• by the state, since the public authorities in order to accumulate sufficient cover. petition possible among the pools, let alone are often confident of their ability to cover It Is clear that this kind of market does not eliminate the need for such a system. the risk themselves. The majority of nu• make for flexibility. We may reflect that clear plants now in existence still serve the pools, consisting in many countries of Increase capacities! research purposes and have no commercial well over a hundred insurance companies— value. But the new plants will mainly be often with small or even trifling contribu• In the course of its close collaboration designed to generate electricity. It is to be tions—can be very ponderous organisations, with the nuclear insurers Euratom has hoped that the majority of these power whose decision-taking machinery is liable repeatedly expressed the hope that insurers plants and other commercial plants—in• to be far more sluggish than that of a single would extend their capability to the utmost cluding those which are state property— insurance company. An escape from this possible limit. It based this hope upon the will be insured. fact that the various insurance companies 3. In order not to have to surrender unconditionally exhibit very different degrees of boldness Third party damage Co pressure from a monopolistic nuclear insurance in regard to the nuclear field, that com pan i es business, whether as regards insurance conditions or premiums, the Dutch Atomic Liability Law of 1965 in comparable situations make very varying Up to now we have confined our remarks envisages the possibility of the state covering for risks sums available, and that for example the to insurance against losses restricted to the in exchange for premiums, in the same way as an ordinary insurer, and thus competing on the in• British insurance market is much more plant. But another branch of nuclear insur• surance market and insuring private undertakings. enterprising than the continental, so that ance is equally important—civil liability Until now, however, this possibility has not been translated into practice. on occasion the British pool assumes up to insurance, i.e. insurance against claims

87 advanced by third parties against the plant Liability in the Field of Nuclear Energy, of — They also provide that this liability operator in respect of damage caused by 29 July 1960, (Paris Convention), and the regulation shall be valid in all the signatory the plant. Here again the vexatious capacity Brussels Supplementary Convention to the states—that is in almost all European states problem arises. Commercially these two Paris Convention on Liability in the Field of west of the Iron Curtain.5 This is very im­ aspects cannot be considered in isolation. Nuclear Energy, of 31 January 1963 (Brus­ portant for the nuclear industry and for In the event of a serious accident with sels Convention), both in the version of insurers, since nuclear damage can extend third­party damage which had to be met 28 January 1964.4 over wide areas and transcend state bound­ from civil liability insurance, it is fairly Here are briefly the principles of the Con­ aries. This European liability regulation safe to assume that the plant itself would al­ ventions: will greatly simplify ¡nsurance and licensing so be damaged, and that payments would — They introduce the so­called absolute procedures. Furthermore a uniform regula­ also have to be made on plant insurance liability principle, under which the instal­ tion is important for international trans­ policies. The insurers' risks would thus lation operator is liable irrespective of port. It also facilitates reinsurance. snowball. The insurers have therefore fault. Compensation is therefore guaranteed declared themselves unwilling to cover in all cases. civil liability risk up to the maximum — The Conventions envisage a so­called Nuclear damage and state intervention credible amount of damage, but only up channelled liability, by virtue of which the to a certain ceiling. installation operator—and only the operator— All the above principles are important for is I ¡able for nuclear incidents connected with nuclear insurance; the provisions of the his installation, even when a third party Paris Convention on the limitation of liabil­ The new nuclear civil liability law is to blame. ity, however, are really vital. The Conven­ — The Conventions also envisage that the tion limits the installation operator's lia­ A brief reference must be made at this installation operator shall be required to point to the new European Nuclear Liabil­ provide a security or a financial guarantee 5. On 28 October I965 the Euratom Commission ity Conventions. With Euratom's collabor­ ensuring that the party liable for damages issued a recommendation for the alignment of the ation two European Nuclear Liability Con­ can meet his obligations in all cases. implementing legislation of the Community Member States on these Conventions. In the spring of I966 ventions have been elaborated, containing the Conventions are not yet in force, because they a new and uniform set of provisions. These 4. cf. Dr. Reinhart Bauer's article "Euratom and the have not yet been ratified by a sufficient number of Questions of Liability and Insurance in Nuclear Ener­ Member States. The Euratom Commission is pressing are the Paris Convention on Third­party gy" in No. 3/I962 of Euratom Bulletin. for speedy ratification.

Π^ί^ί/Λ~

88 The high flux research reactor at Petten (Netherlands)

bility to 15 million u.a. The signatory states can however raise the liability ceiling in line with the possibilities offered by the insurance business, or reduce it to 5 million u.a. This restriction of liability is designed mainly to meet the wish of the insurers, who were unwilling to take on a major third party risk in addition to the property risk. What solution have the Community coun• tries chosen? Belgium 10 million u.a. (draft law), France 10 million u.a., Italy 5 million u.a., Holland 15 million u.a. and Germany an amount to be fixed for each plant individually according to particular criteria. In the USA, incidentally, the pre• vious liability ceiling of 60 million dollars accepted by the insurance companies has now been raised to 90 million. This restriction, which, as indicated, meets the insurers' wishes and also the economic interest of the nuclear industry, whose premium obligations are thereby obviously reduced, is not without its problems. Should third party damage occur which exceeds these liability limits, the victim can clearly not be left without compensa• tion. But the Paris Convention made no provision for compensation exceeding the basic limit of 15 million u.a. The Euratom Commission therefore took the initiative in drafting the Brussels Sup• plementary Convention, which ups the liability ceiling. Almost all the signatory states of the Paris Convention—except ir % Portugal, Turkey and Greece—have sub• scribed to it. Under this Convention the state in which the installation is located pays compensation up to 70 million u.a. in the event of damages exceeding the so-called first instalment normally covered by the insurance companies. Should the damage be still greater, then all the signa• tory states combine to pay compensation between 70 and 120 million u.a. (If contrary to expectation even greater damages are entailed, the compensation will be settled ad hoc). The states thus bear the risk of major damage, since the insurance business has declared its inability to do so.

The 200 MWe nuclear power plant at Latina (Italy) Many experts consider damage on such a fact that the signatory states of the Paris scale as an extremely remote contingency. Convention not only arrange cover but But whether the possibility can be com• provide it themselves. When the signatory pletely ruled out or whether merely an states license an installation, they must improbability is involved, we can be sure vouch for the existence of an adequate that in most cases the third party damages guarantee. If they license an installation, will lie within the limits of the first therefore, and there is no insurance at all instalment, i.e. within the purview of or Inadequate insurance, with no other private insurance. But should damages to financial guarantee, the licensing state the extent of 120 million u.a. ever occur, must itself stand surety. If a nuclear civil the insurance business would in the extreme liability is not insured, the states assume case cover only 4%, and the state the responsibility. remaining 96%. Anyone who supports the This is of particular significance because the principle of a liberal economy based on insurance does not—as is otherwise custom• private initiative must regret this state ary in third party insurance—cover each intervention. It is to be hoped—and Eura• new case of damage afresh up to the sum tom expressed this hope at the Berlin insured. The nuclear insurers provide Colloquium—that European nuclear in• merely a "write-off policy", i.e. they insure surance will emulate Its American counter• only up to a fixed maximum sum per part, further extend its capacity for third installation or per transport. Once this party liability, and thus reduce and perhaps sum is spent by one or more previous eventually eliminate the part which the incidents, the ¡nsurance is no longer valid. state has to play. In such case the state then becomes liable.6 Since this amplified capacity can be used The same applies if the ¡nsurance fails to not only to widen the liability borne by cover particular cases owing to exclusion insurance, but also to ensure that, at a clauses in the ¡nsurance contract. The constant level of demand, the nuclear in• knowledge that should private ¡nsurance surance capacity on offer rises above the not be operative, the state will guarantee requirement per risk and thus creates the compensation, has led to a tendency on the basis for a competitive market, we believe part of some insurants to accept a policy that it is expedient to apply ¡t first of all to containing many exclusion clauses and stimulate competition and only later to limitations, meaning of course lighter proceed to raise the nuclear liability ceiling. premiums, thus leaving a large part of the On the other hand it seems advisable for the guarantee to the state, which supplies it Member States to bring into line the ceiling cost-free. This is clearly undesirable to the of the first instalment, either at 10 million state, both from the standpoint of govern• u.a. or at 15 million u.a. The differences in ment finance and on general economic first-instalment liability lead to a number grounds, and the states can influence the of difficulties, particularly as regards inter• formulation of policies in that they must national transport. authorise them. But there are limits to this influence, since of course in each state only one insurance pool will offer a policy. The states have, however, another lever If insurance does not cope ... at their disposal. While the Paris Convention indeed prescribes that the state must Another complicated problem is raised by guarantee any installation which it licenses, the exceptions and limitations of insurance there is nothing to prevent the state claim• protection. Every insurance contract has ing on the installation operator subse• them. Now nuclear third party insurance quently. Legislation in many countries is not an ordinary voluntary ¡nsurance. It makes provision for such recourse, although bears a close resemblance to a compulsory ¡nsurance, such as we are familiar with in most European countries, e.g. for vehicle third party liability. But it differs from a compulsory ¡nsurance in 6. The licensing authorities will however require that that the Paris Convention admits other the sum insured be made up again to the full amount after a payment of compensation, and in the event of financial guarantees in addition to insurance, non-compliance will order the installation to close e.g. bankers' guarantees or the deposit of down. A further accident could clearly occur before it was possible to replenish the sum insured by supple• securities. A further difference lies in the mentary or new insurances.

90 View of the experimental fast neutron reactor RAPSODIE (Cadarache, France)

joint elaboration of the framework policy which, now completed for fixed plants, is to be supplemented by a similar text for nuclear transport insurance. This will how• ever raise a not inconsiderable number of still unsolved technical problems stemming from the complexity of the provisions of the Paris Convention, the traditional rules and practices of marine insurance, the international liability regulations for air, sea and road transport which overlap with the Paris Convention and the fact that transports often take place outside the geographical limits of the Paris Convention, with the result that other national and international insurance liability regulations must also be taken into account.

Risk assessment

An issue which gives rise to lively discussion between insurers and insurants is the assess• ment of individual hazards. The various plants and transports must of course be assessed on their merits according to their particular degree of danger. The Euratom Commission has brought up this point in the various colloquia held with insurers and insurants. At the last Conference, organised in Berlin in the summer of 1965, it was resolved that Euratom should sys• tematically examine risk assessment in this new field in conjunction with industry, electricity producers, the technical inspec• tion authorities and the insurers. We may assume that within a few years— whether ten, twenty or thirty—the nuclear business will be just another branch of insurance, with no more and no less prob• this is usually restricted to accidents at• as a counterpart to the uniform liability lems than any other field. But we already tributable to the operator. and coverage rules of the European Liability need this insurance now while it still has Conventions. Such uniform principles are to cope with exceptional conditions. If Euratom framework policy required if liability is to be regulated at nuclear insurance is to become a usable European level. The joint elaboration of such tool for nuclear industry, the insurers and In collaboration with the nuclear insurers a policy by insurers and insurants with the whole European economy, there must and the Industrial Insurants' (UNICE) and Euratom's help was particularly desirable, be sympathetic and prudent co-operation Power Producers' (UNÍPEDE Committee since in the absence of competition the between all business circles, as well as be• for the European Community) Associa• insurance terms cannot be determined by tween them and the European and national tions, the Euratom Commission has drafted the free play of supply and demand. The authorities. Euratom wishes to discharge its a framework policy for third party nuclear Euratom Commission therefore warmly duty of promoting nuclear energy by acting liability insurance which lays down uniform welcomed the readiness on the part of as "honest broker" between the nuclear principles and rules and is intended to serve both insurants and insurers to help in the industry and the insurance business.

91 EURATOM NEWS

Ivory Coast and Chad—Schemes for preservation of One of the most promising methods of preserving it is by a combination of irra• fish and meat by irradiation diation and refrigeration (see page 73 of this issue). During the first stage of the project, studies will be performed in the laboratories of the Euratom//TAL Asso• The director of the Euratom//TAL Associa• the preservation of fish and meat by ciation in the Netherlands on a series of tion and a representative of Euratom's irradiation and make a direct contribution techniques combining the use of irradiation biology departments paid a visit to the to solving one of Africa's major problems, and different types of refrigeration, to see Ivory Coast and Chad during May on namely, that of the lack of protein in the which offers the most economical method behalf of the European Development Fund diet. of transporting fish to the interior of the for Overseas Countries and Territories, The first project deals with the preservation country without its nutritive value being which is a Common Market body. of fish In the Ivory Coast. About 20,000 affected. The purpose of the visit was to obtain tons of sardines are landed annually off In the course of a second "pilot" stage in additional data for the preparation of two Abidjan, the bulk being eaten in the locality. the Ivory Coast, the methods will be tested projects covering the utilisation of nuclear As things stand at present, only a small in local conditions and in local distribution techniques in the African countries which amount is sent elsewhere. The problem networks. Finally, the third phase will are associate members of the European is how to transport the fish further into entail the installation of an irradiation Community (see Euratom Bulletin, Vol. V, the interior of the country while ensuring unit capable of handling at least 10,000 1966, No. 1). These two projects concern that it is still fit for human consumption. tons of sardines a year. The cost of the first stage will run to about 15,000 dollars, this sum being used to cover the cost of transporting samples of fish from Abidjan to the Netherlands. The pilot stage is estimated to cost 100,000 dollars, while the cost of the final installation will amount to about 600,000 dollars. The second project concerns the use of irradiation for preserving meat in Chad. It was originally planned to combine economic and sanitary motives ¡n wiping out tenia larvae in butcher's meat, but it emerged that irradiation was not warranted on either of these two grounds above. Meat preservation, on the other hand, is an economic problem of the greatest impor• tance to Chad. Livestock is raised in Chad not only for consumption on the home market, but also for export to othe r African countries, mainly Congo-Brazzaville and Nigeria. The animals are either slaughtered in Chad and immediately transported by air or else are driven to their destination on foot, which leads to loss of weight. Neither of these is a very economical method, and it would be far better to set up, instead, a distribution system based on the preservation of meat on an industrial scale. A situation would thus be created whereby the distribution networks could be extended.

92 Like the first, this project is divided up into serving meat and, at the same time, of 100,000 for the second and 600,000 for the three stages. Firstly, there is an exploratory killing off any tenia larvae in it. This would third. phase, which would be carried out in the be followed by a series of small-scale trials Since the necessary data are now on file, Netherlands and would involve studies of in local conditions. Finally, an irradiation the European Development Fund is to be the various possible combinations of irra• installation would be set up at Fort Lamy. asked to take a decision with regard to the diation and refrigeration with a view to The cost of this project is estimated at financing of the first two phases of each developing an economic method of pre• about 20,000 dollars for the first phase, of these projects.

Fuel for Lingen, Dodewaard and Obrigheim reactors

In May 1966 the Euratom Supply Agency the German firm of the right to use and signed two contracts for the supply of consume the fuel supplied under the first enriched uranium fuel to the KWL (Kern• contract. kraftwerk Lingen GmbH) 250 MWe boiling- Similar contracts were signed, in June 1966, water power reactor at Lingen, Lower covering the supply of enriched uranium Saxony, Federal Republic of Germany. The containing 290 kg of uranium-235 to the first, under the US/Euratom Agreement of GKN (Gemeenschappelijke Kernenergiecen• Co-operation, was with the USAEC for the trale Nederland) for its 54 MWe boiling- supply of enriched uranium containing 970 water power reactor in Dodewaard, and, kg of uranium-235. The second, between in July 1966, covering the supply of 1.160 the constructors of the reactor, the All• kg of contained uranium-235 to the KWO gemeine Elektricitäts-Gesellschaft (AEG) and (Kernkraftwerk Obrigheim GmbH) for its 300 the Supply Agency, covers the transfer to MWe boiling-water power reactor.

The Lingen nuclear power plant (Federal Republic of Germany) under construction off the Dortmund-Ems-Canal

General view of the Dodewaard nuclear power plant (Netherlands)

93 EURATOM NEWS

Comprehensive study on pressu ri sed-water reactors accelerate corrosion of the materials, etc. Euratom is at present in the process of negotiating a contract with FIAT under Under a contract drawn up with Euratom it, e.g., boron in the form of boric acid, and which this company would carry out the in July 1966, the Ente Nazionale per l'Energia to adjust its concentration without diffi• various analyses as well as the interpretation Elettrica (ENEL) is to carry out a major culty. It is thus possible to dispense with of the data obtained. research programme on pressurised-water some of the classical control rods, namely The Soc/été d'énergie nucléaire franco-belge reactors with the aid of its 257 MWe those which are gradually withdrawn from des Ardennes (SENA), is likewise expected power reactor at Trino Vercellese. the core as the fuel is used up and the to collaborate on this programme under its The general aim of the research programme reactivity decreases. contract of participation with Euratom. The is to increase and disseminate technical The programme will deal with twelve power reactor built for this company at data concerning pressurised-water instal• different technical problems. Chooz in the Ardennes (which is just about lations and more particularly "soluble Information is to be obtained, for instance, to receive its first core charge) is in fact poison control" or "chemical shim", to on possible tendencies on the part of boron of the same type as the Trino Vercellese which these reactors are especially well compounds to become concentrated and plant. SENA will therefore be able to make suited. precipitate on the surfaces of the core under direct use of the study results. The pressurised primary circuit operates surface boiling conditions, thus altering the The research will take three and a half in closed cycle, so that it is possible to reactivity; steps will be taken to ensure years and a budget of about 1,400,000 inject a neutron-absorbing substance into that the presence of boric acid does not dollars has been earmarked for it.

A prototype isotope generator tricity by thermoelectric conversion. Their The prototype to be built by the Soc/été The Société d'exploitation des matériels main appeal lies in the fact that they are d'exploitation des matériels Hispano-Suiza Hispano-Suiza of Bois-Colombes, France, sturdy, independent sources of electric will have an output of about 0.2 watts and has been asked by Euratom to design energy which can be used for special pur• will be equipped with bismuth telluride and build a prototype of a thermoelectric poses where normal generators cannot be thermocouples and strontium-90 titanate radioisotope generator. This will be the employed. For instance, radioisotope gener• heating elements of about 1,000 curies. first device of its kind to be developed by ators can be used to supply current to a private company in the Community. radio emitters fitted in underwater pipe• When the project is completed, the gener• In these devices, the energy emitted by a lines to enable them to be located. They ator will be handed over to Euratom and radioisotope in the form of radiation is can also be employed on buoys, automatic will be used for demonstration purposes transformed into heat and then into elec• weather stations, etc. in the various Community countries.

Collaboration in the field of direct conversion acquired by the other and is entitled to a cost-free licence to exploit the patents filed by the other, as well as being allowed to A contract for co-operation in the field relating to the transfer of heat to such grant sub-licences under certain conditions. of direct conversion has been concluded generators and methods of cooling them. This type of co-operation may be extended, between the Euratom Commission and the Under the agreement the partners are to on terms which still have to be negotiated, B.B.C. Company of Mannheim, which car• co-ordinate their work, exchange knowhow to any Community concern which is in ries out work on direct conversion with and assist each other with regard to both a position to make a significant contribu• financial backing from the German Federal personnel and equipment. tion to the development of direct conver• Ministry for Scientific Research. Each partner assumes responsibility for the sion techniques. The agreement covers, in particular, the costs incurred by its own activities. As Interested parties are requested to contact design and construction of thermionic regards the knowhow stemming from the Euratom, Directorate General for Research generators, their use in conjunction with research to be carried out under the con• and Training, 51 rue Belliard, Brussels 4, reactors and radioisotopes and the problems tract, each partner may use the experience Belgium.

94 Uranium propecting in the Community necessary—to draw the attention of in• terested parties to the possibility of dis• covering uranium deposits within the terri• tories of the six member states. In 1963 the Euratom Commission published this report, it is apparent that the Com• With this object in view the Euratom Com• a report by the Supply Agency's Consulta• munity will become a major consumer in mission, as empowered by Article 53 of the tive Committee entitled "The problem of the uranium market and, furthermore, will Treaty, issued a directive to the Supply long-term resources and supply of uranium" find itself dependent on other countries for Agency to instruct its Consultative Com• in which the question of uranium supplies its future supplies. mittee to draw up a report, with the help to the Community was reviewed in the On these grounds it seemed advisable, of geologists of the member countries, on light of total Western world resources. before going into the development of uranium prospecting in the Community. From the conclusions which emerged from external sources—which is already proving Their report, which was published recently, shows that the surveys performed up to 1964 detected resources that can be devel• oped at a price of not more than $ 8 per lb U3Os, amounting to some 31,000 metric tons of uranium metal. The geologists believe, moreover, that an exploration programme carried out in three of the Community countries, France, Germany and Italy, should reveal further uranium deposits workable at comparable prices. It is hard to predict the exact tonnage of these suspected resources; but the geolo• gists think they might be as much as 20,000 tons in France, 10,000 tons in Germany and 10,000 tons in Italy, which, in their view, would make a greater prospecting effort worthwhile. The authors of the report hope that closer relations will be set up among the experts of the various Community countries; in addition, they particularly recommend that the six countries collaborate to organise more frequent exchanges of experts, so that the work may go forward with maxi• mum efficiency.

Map of uranium deposits and main mineral indications in the European Community

95 EURATOM NEWS

Petten H FR reactor uprated The power of the High Flux Reactor (HFR) Euratom Economic Handbook at Euratom's Petten research establishment has been uprated from 20 to 30 megawatts. Thanks to the higher neutron flux and higher ¡rradiation capacity which this en• The Euratom Commission will shortly pub• tails, it will be better able to meet the lish an "Economic Handbook" proposing Community's growing irradiation require• a standard method of calculating nuclear ments. This result was obtained without power generating costs. introducing many significant modifications: the number of fuel elements in the core Almost since the very beginning of nuclear has been slightly raised and hydraulics and power generating history the need for neutronics studies carried out at the estab• standardisation in this field has been felt; lishment have made it possible to redesign even today enquirers find it difficult to the core so as to increase their individual make accurate cost comparisons between rating. power reactors of different types, such is the variety of the methods used when making estimates.

The first step towards a uniform method for the European Community was taken in October 1963 at a symposium held by Euratom in Venice. For the first time a basic scheme was discussed with represen• tatives of all interested parties. Shortly The High Flux Reactor in Petten (Netherlands) afterwards the Commission signed a con• tract with the French Commissariat à l'éner• gie atomique, the French firm Indatom, the German firm Siemens-Schuckert-Werke AG and the Italian firm SORIN, who were instructed, on the basis of the scheme dis• cussed in Venice, to carry out the studies Radioisotopes for detecting wear in Diesel engines required for the compilation of the "Eura• tom Economic Handbook". Diesel engines are subject to a particular Among the several attempts already made kind of wear which especially affects their to arrive at a deeper understanding of the In the meantime, Euratom received the water-jackets. The trouble can be traced phenomenon is a programme recently actual operating data of the first power back to a "cavitation" phenomenon, caused launched by FIAT of Turin under Euratom reactors in which it has a financial stake. by vibration, but it is still fairly mysterious. contract. A measuring apparatus, relying On the basis of these data the Comitato Apparently bubbles form in the circulating largely on the use of radioisotopes, is being Nazionale per l'Energia Nucleare evolved, liquid and, when they collapse in the neigh• developed to assess the role of various under contract to Euratom, a method of bourhood of the water-jacket walls, do so parameters: amplitude and frequency of calculating the fuel cycle cost. with enough violence to remove particles vibration, temperature and pressure of the of the wall material. fluid, the effect of deaeration, etc. The "Economic Handbook" relies heavily on This problem is serious in the case of large the results of all these studies. It should Diesel engines, such as those used In ships The main objective of this Euratom research be stressed that it is not Its purpose to or for electricity generation, which have contract is to devise an apparatus which, establish criteria for assessing the relative to be designed for many years of almost if not transportable, will at least be easy to merits of different electricity-producing constant use. Attempts have been made to reproduce. Thus other Diesel engine manu• plants, whether nuclear or conventional. get round it by applying additives but no facturers or other firms with similar wear It merely presents a method of calculating fundamental cure seems to have been found problems due to cavitation will be able to a power generating cost which it is hoped yet. use this apparatus. will meet with general acceptance.

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* Besides the English edition, EURATOM Bulletin Is published in German, French, Italian and Dutch. The CIRENE design: uranium metal or oxide? perusal to be unsuited to their needs, and will be sure of having at any given moment a complete overall picture of the latest developments in their particular field. The CIRENE programme, it will be recalled, far acquired on the irradiation stability of The CID intends shortly to make these was launched with a view to developing a uranium metal, it appears unlikely that ¡t services available to all scientists and engi• family of natural-uranium-fuelled reactors can be employed at the high burnup levels neers in the Community countries. with heavy-water moderator and boiling feasible with a heavy water moderator. This achievement has been made possible light-water coolant (cf. Euratom Bulletin Another drawback is that, according to by an alliance between man and machine, Vol. IV, 1965, No. 2, pp. 54-60), under a con• uranium-metal/heavy-water compatibility for while the machine can perform numer• tract of association concluded between studies carried out, a cladding failure would ous routine operations quicker and better Euratom and the Italian Atomic Energy give rise to serious difficulties. These two than man, in the last resort it is man's Commission (CNEN). The major part of the stumbling-blocks are not insuperable, but intellectual capabilities which enable him work was performed by the Centro Infor• a considerable research effort would be to programme and feed the machine. mazioni Studi Esperienze (CISE) in Milan. required in order to overcome them. Once again it is noteworthy that a project From the outset of the conceptual design Uranium metal was therefore finally which has no rival in the world in the studies, attention had been given to both abandoned and the oxide formula adopted. nuclear field has been brought to fruition Zircaloy-2-clad uranium oxide rod bundles A point in its favour is that any enrichment by a Community effort. and uranium metal tube clusters with in• decided upon would be of greater advantage ternal cooling. A comparative study of the to the oxide, which is not affected by the two reactor versions (each of 500 MWe) burnup limitations inherent in the metal. which these fuel types would entail shows no clear advantage of either one over the Also, the oxide clearly appears to be more other. suitable for use with superheat channels. Admittedly the uranium metal version of• Now that the choice has been made, CIRENE fers the greater reliability from the reactor has come to be a closer relation of the control and safety angle. Canadian CANDU-BLW and the British On the other hand, in view of the data so SGHWR systems. Five-year index to Transatom Bulletin

Since the beginning of 1961, Transatom Bulletin, which is published by Euratom, has been facilitating the West's access to Scientific and technical documentation takes a step the nuclear literature of the East by announc• forward ing systematically Eastern nuclear docu• ments (e.g. in Russian, Polish, Japanese, etc.) which exist translated into a Western The Centre for Information and Documen• stracts; these replies are obtained by tap• language. tation (CID) of the European Atomic ping the magnetic memories of a powerful Energy Community has just placed a ma• computer in which are at present stored Transatom Bulletin has decided to publish a chine documentation service at the disposal references on nearly 500,000 publications, cumulative five-year index covering the of Joint Research Centre staff-members to which about 120,000 new publications years 1961-1965, which should be available and Euratom contractors covering the will be added in an average year. shortly. The price of this volume, in which entire field of the peaceful applications Parallel to this "question-reply" service, there will be about 120,000 entries, will of nuclear energy. it is intended to send regularly to inter• be approximately 10 dollars. It can be At the CID, a team of engineers and scien• ested subscribers a selective bibliography ordered from: Transatom Bulletin, C.I.D., tists from the six countries will hence• accurately and exclusively covering their 51, rue Belliard, Brussels 4 (Belgium). forward be able to reply at short notice to field of activity. They will thus avoid the technical questions addressed to it by loss of time occasioned by consulting sending complete bibliographies and ab• numerous documents which prove after topi raaioisotopen s hip propulsion schiffs antrieb propulsion na vale propulsione nava le scheepsvoortstuwi ng biology biologie biologie biologia bio logie medicine medi zin médecine medicin u^ a geneeskunde healt pj h protection gesundh çr) eitsschutz protection c^> sanitaire protezione s C3> anitaria bescherming \0 van de gezondheid VO automatic data proces <£ sing automatische inf ^A ormation information J¡^ automatique informa Q zione automatica auto ζ_) matische verwerking van gegevens insura nce versicherungswes en assurances assicura zione verzekeringen economics Wirtschaft économie economia e conomie education and training ausbildu ng enseignement inse gnamento onderwijs en opleiding power reactors leistungsreak toren réacteurs de pu issance reattori di po tenza energie reactor en nuclear fusion ke rnverschmelzung fusi on nucléaire fusione nucleare kernversmei ting radioisotopes r adioisotope radioisot opes radioisotopi ra dioisotopen ship pr opulsion schiffsantrie b propulsion navale propulsione navale scheepsvoortstuwing biology biologie biolo gie biologia biologie medicine medizin mé decine medicina gene eskunde health pro tection gesundheitssc hutz protection sanit aire protezione sanita ria bescherming van de gezondheid auto matic data processing automatische informa tion information auto matique Informazione automatica automatis che verwerking van g egevens insurance v ersicherungswesen as surances assicurazioni verzekeringen econ omics Wirtschaft èco nomie economia eco nomie education and training ausbildung enseignement insegn amento onderwijs en opleiding power reac tors leistungsreakto ren réacteurs de pu issance reattori di po tenza energie reactor en nuclear fusion ke rnverschmelzung fusi on nucléaire fusione nucleare kernversmei ting radioisotopes r adioisotope radioisot opes radioisotopi ra