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HEAVY WATER at ASWAN by Dr HEAVY WATER AT ASWAN by Dr. Victor Thayer In response to a request from the Government of the United Arab Republic, two experts were sent by IAEA, at the beginning of November,to Egypt, Mr. B.V. Nevsky (USSR) and Dr. Thayer (USA). Mr. Nevsky examined the possibilities and economics of ex­ tracting uranium from ores rich in phosphates, which are plentiful in Egypt. His report was not available when the Bulletin went to press. Dr. Thayer has reported to the Director General on the possibilities and the economic interest of producing heavy water by the electrolytic method as a by-product of an ammonium nitrate fertilizer factory now being constructed at Aswan. Dr. Thayer is a member of the Atomic Energy Division of the Du Pont Company and is working as a heavy water expert at the American Atomic Energy Commission's Savannah River project. We publish below excerpts from Dr. Thayer's report. SUMMARY power for the fertilizer plant is to be supplied by a hydroelectric plant now under construction at the 1. The proposed production of heavy water as a present Aswan dam. Construction of this power by-product of fertilizer (nitrate) manufacture at plant is well advanced and completion is scheduled Aswan on the upper Nile is technically feasible. for late in 1959. The separation of heavy hydrogen (deuterium) for (b) THE SCIENTIFIC AND TECHNICAL FEASI- subsequent conversion to heavy water could be done BILITY OF THE PROJECT either by catalytic exchange or by liquefaction and distillation. The choice of process should be made Recovery of deuterium from industrial hydrogen on an economic basis. and particularly from electrolytic hydrogen (the type to be produced at Aswan) has been demonstrat­ 2. Provided that firm contracts are obtained for ed to be feasible. Heavy water is now being pro­ delivery of equipment at guaranteed prices and with duced from such hydrogen in Norway (Rjukan) and guaranteed performance, and provided that such Canada (Trail). Several processes for recovery prices are in reasonable agreement with preliminary are available including catalytic exchange with water estimates, the heavy water produced at Aswan should in the vapour phase (Trail process), distillation of be competitive in cost with that produced elsewhere. liquid hydrogen (plant recently started by Farbwerke Hoechst), catalytic exchange with water in liquid 3. The future market for heavy water is difficult phase (pilot plant being operated in West Germany to predict. It is important to note first, that there by Prof. Becker with the support of Uhde, a sub­ is a very large production capacity in the USA, most sidiary of Farbwerke Hoechst). Catalytic exchange of which is idle due to lack of demand, and second, between, ammonia and hydrogen has also been that there is a relatively small production outside suggested, but experimental data in support of this of the USA that is sold at prices higher than that at process is not adequate to justify including it in the which the U.S. Government sells heavy water. The list of available processes. future of the market is necessarily contingent upon the possibility of future free sale by the U. S. Govern­ (c) ECONOMICS OF THE PROPOSED PLANT, ment. INCLUDING COST ESTIMATE FOR THE HEAVY WATER PRODUCED 4. Comments as to further IAEA participation in the project are given in section (j) of this report. Cost of heavy water (including capital charges) derived from electrolytic hydrogen should be in the (a) GENERAL DESCRIPTION, EXTENT AND range of $ 20 to $ 30per pound depending principally PURPOSE OF PROJECT upon the capital cost of the plant and the rate of capital written off. Firm capital costs are not yet The purpose of the project is to recover deuterium available, although preliminary estimates have been gas (heayy hydrogen) from industrial hydrogen. The obtained. Operating costs, excluding capital char­ deuterium gas will then be converted to heavy water. ges, appear to be in the range of $ 7 to $ 13 per pound. The industrial hydrogen to be thus used as raw material will be available at the fertilizer plant now It is important to note here that, in view of the being built by Egyptian Chemical Industries (Kima) technical progress that has been made in recovering at Aswan. In effect, the proposed heavy water pro­ heavy water directly from natural water, there does duction would be a by-product of the fertilizer plant. not appear to be any inherent economic advantage in Construction of the fertilizer plant is well advanced producing heavy water as a by-product of industrial and start-up is scheduled for early in 1960. hydrogen. Over the long term, direct production might very well turn out to be cheaper. For the As a matter of interest, it may be noted that the present it can be said that costs for both the direct fertilizer to be produced at Aswan is a mixture of and by-product methods are in the same range. ammonium nitrate and calcium carbonate adjusted Pintsch Bamag (Fed. Rep. of Germany) are known to contain 20. 5% nitrogen. It may be noted also that to be working on the direct H2S - H2O process. 20 Although the Savannah River technology on this pro­ mentioned as a possible location because of the cess is for the time being not available as public availability of geothermal (underground) steam in information, the future publication of this infor­ Iceland. mation must be considered a possibility. Pintsch Bamag (Fed. Rep. of Germany) has pub­ (d) THE OUTLOOK OF THE HEAVY WATER MAR­ lished a process design for the H2S - H2O process: KET AND THE POSSIBILITIES OF EXPORT TO Chemie - Ingenieur - Technik, 30, No. 5(1958) by THE EXTENT INFORMATION IS AVAILABLE Prof. G. Weirs. It is quite possible that Pintsch Bamag may soon be in a position to build a plant Pertinent comments on the heavy water market using this process. Costs in the Fed. Rep. of Germany are summarized in the following paragraphs : should be lower than in U.S.A. due principally to lower wage rates both in construction and operation. 1. Existing Capacity West German research on a liquid phase catalytic U.S.A. Installed capacity is about 1000 short tons hydrogen-water exchange process was reported at (900 metric tons) per year. Less than on • half is Geneva by Prof. Becker (Paper No. 1000). operating due to lack of demand. Process used is H2S - H2O exchange for direct recovery of heavy L'Air Liquide (France) reported at Geneva about water from natural water. their pilot plant studies on hydrogen liquefaction and distillation. France is reported to be working Canada. Trail plant makes about 8 short tons per intensively on this and other methods for producing year. Marginal (out-of-pocket) cost is probably less heavy water. than U.S. price of $ 28 per pound, although the full cost including capital charges is probably more than In general, it may be said that technical interest $ 28 per pound. Canada buys heavy water from the in heavy water production is at a high level in many U.S.A. areas. In addition to the countries mentioned, others including Sweden, Switzerland and Japan are Norway. Heavy water was produced at Rjukan in reported to be doing research on this subject. Norway as far back as 1940. Current Norwegian production is reported to be of the order of 10 to 12 tons per year. 3. Prices Fed. Rep, of Germany.Farbwerke Hoechst repor­ The U.S. price of $28 per pound reflects operat­ ted at Geneva that they put into operation in June ing cost (including full overhead) of about $14 and 1958 a plant for liquefaction of distillation of capital charges of about $ 10 based on about a 16 2/3 ammonia synthesis gas (mixed gas, 75% H2, 25% N2I year write off. The reported West German purchase Design capacity 6 tons per year of heavy water. If offer of 800 DM/kg (about $ 87 per pound) is appa­ this plant is successful, Farbwerke Hoechst would rently a "free market" price that does not involve presumably build a larger plant. negotiating with a government. This price would very probably come down if the Fed. Rep. of Ger­ Soviet Union. The technology of distilling in­ many builds a large scale plant, for instance by the dustrial hydrogen to produce heavy water was dis­ 'i2S - H20 process. cussed by Russian authors at the Second Geneva Conference. Although no definite information is 4. Prospective Needs for Heavy Water for Use in available as to the amount of heavy water actually Reactors being produced in the Soviet Union, the reported development of heavy water moderated reactors in Britain's large power program is based on natural the eastern European trading area leads to the in­ uranium and graphite. They are pushing this hard ference that significant quantities of heavy water and presumably can get along without heavy water. are produced there. Canada has announced an experimental or "pilot" 2. Projected Capacity power reactor based on heavy water and natural uranium. Canada's requirements for heavy water, India has a developed proposal for 14 T/year beyond that produced at Trail, are obtained from plant, at the Bhakra Nangle project on the Sutlej the U.S.A. River, based on distillation of hydrogen produced at a fertilizer plant. As far as is known, contracts It is probably too early to say how the heavy water have not yet been placed. moderated power reactor will compare, in the long run, with other types. It should be noted, however, A study team fromOEEC (Organization for Euro­ that Canada's emphasis on the heavy watermoderat- pean Economic Cooperation) is making an extensive ed reactor is based on the availability of heavy study of allprocesses to determine the desirability water at $ 28 per pound.
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