Properties and long-term behaviour of bitumen and radioactive waste- bitumen mixtures Hubert Eschrich Eurochemic, Mol, October 1980 PROPERTIES AND LONG-TERM BEHAVIOUR OP BITUMEN AND RADIOACTIVE WASTE-BITUMEN MIXTURES Hubert Eschrich Eurochemic, Mol, October 1980 This report concerns a study which was conducted for the KBS project. The conclusions and viewpoints presented in the report are those of the author(s) and do not necessarily coincide with those of the client. A list of other reports published in this series is attached at the end of this report. Information on KBS technical reports from 1977-1978 (TR 121) and 1979 (TR 79-28) is available through SKBF/KBS. PROPERTIES AND LONG-TERM BEHAVIOUR OF BITUMEN AND RADIOACTIVE WASTF-BITUMEN MIXTURES ABSTRACT This report consists of two main parts. Part I represents a survey of the properties and the long-term behaviour of pure bitumens and mixtures of bitumens with radio- active reactor and reprocessing wastes. This survey includes information on the origin, amounts, and composition of the various wastes considered for bituminization and the different waste bituminization techniques used. The in- fluence of various factors on the quality of waste-bitumen pro- ducts and on the radiological safety during transport, short- and long-term storage of the final products is described. Special consideration is given to the most important safety relevant factors associated to the use of bitumen as matrix mater*t ror radioactive wastes, such as leach-resistance, radio- lysi? K-mical and mechanical stability, combustibility, and micr •' att;.ck. Par •- -onsists of a comprehensive bibliography on the bitumi- on of radioactive wastes, giving about 300 references to tire published from the beginning of the use of bitumen in rac* ?.tive waste management in i960 until the beginning of 1979. Tr? "»ibliography serves at the same time as source for the litera- ti \ referred to in the text of Part I of this report. Metods for the quality control of bituminous materials and some use jl data are given in an annex. LIST OF CONTENTS PART I Page SUMMARY AND CONCLUSIONS 1 1. INTRODUCTION 7 1.1 Background 8 1.2 Scope 9 2. THE PROPERTIES OF BITUMEN 11 2.1 General 11 2.1.1 Definition of terms 2.1.2 General composition and properties 2.1.3 Sources 2.2 Types of Bitumen 16 2.3 Application of Bitumens 16 2.3.1 History 2.3.2 Conventional applications 2.3.3 Applications in nuclear waste management 2.4 Chemical Properties 18 2.5 Chemical Stability 19 2.6 Physical Properties 27 2.6.1 General 2.6.2 Specific density 2.6.3 Coefficient of cubical expansion 2.6.4 Specific heat 2.6.5 Thermal conductivity 2.6.6 Permeability to water vapour 2.6.7 Surface tension 2.6.8 Total surface energy 2.6.9 Resi stivi ty/conducti vi ty 2.6.10 Dielectric strength (breakdown voltage) 2.6.11 Dielectric constant and dielectric loss 2.6.12 Mechanical and Theological properties 2.6.13 Ductility and brittlenoss 2.6.14 Radiation resistance 2.6.15 Summary of physical data 2.7 Health Aspects 42 2.8 Safety Aspects 42 3. LONG-TERM BEHAVIOUR OF BITUMEN 43 3.1 General 43 3.2 Durability of Bitumen 43 3.2.1 Physical hardening 3.2.2 Chemical hardening 3.3 Reactions with Various Materials 45 3.4 Microbial Degradation 46 3.5 Conclusions 48 11 4. RADIOACTIVE HASTES CONSIDERE 49 4.1 General 49 4.2 Reactor Wastes 49 4.2 1 Origin 4.2.2 Amounts and composition 4.3 Reprocessing Wastes 57 4.3.1 Origin 4.3.2 Amounts and composition 4.4 Conclusions 62 5. BITUMINIZATION OF REACTOR AND REPROCESSING WASTES 63 5.1 General 63 5.2 Process Techniques 63 5.3 Process Equipment 64 5.4 Final Product Container 64 5.5 Factors Influencing Final Product Quality 67 5.6 Safety Risks <*uring Bituminization 71 5.6.1 General 5.6.2 Investigations and results 5.6.3 Incidents 5.6.4 Conclusions 5.7 Bituminization Facilities in Various Countries 75 5.7.1 Sweden 5.7.2 Other Countries 5.8 Conclusions 81 6. THE PROPERTIES OF BITUMEN-WASTE MIXTURES 87 6.1 General 87 6.2 Composition and Characteristics of Bitumen-Waste Products (BWPs) 87 6.2.1 Reactor waste-bitumen products 6.2.2 Reprocessing waste-bitumen products 6.3 Storage- and Safety-Relevant Properties of Bitumen-Waste Products 93 6.3.1 Introduction 6.3.? Leach resistance a) General b) Influence of the amount and composition of the incorporated wastes c) Influence of the particle size and distribution (homogeneity) d) Influence of the water content e) Influence of the type of bitumen f) Influence of the bituminization conditions g) Influence of the radiation dose h) Influence of the leachant i) Influence of temperature j) Improvement of the leach resistance k) Conclusions 6.3.3 Radiation stability and effects a) General b) Generation of radiolysis gas and swelling c) Changement of the leach rate and other properties d) Conclusions m 6.3.4 Thermal stability and effects 6.3.5 Sedimentation and homogeneity a) General b) Experiments and results c) Conclusions 6.1.6 Combustibility and explosiveness a) General b) Soviet-Union: test results c) United States: test results d) Federal Republic of Germany: test results e) France: test results f) Conclusions 6.3.7 Mechanical stability a) General b) Results c) Conclusions 6.3.8 Swelling a) General b) Results c) Conclusions 7. INTERIM STORAGE 121 7.1 Genial 121 7.2 Storage Facilities 121 7.3 Conclusions 125 8. TRANSPORTATION 127 8.1 General 127 8.2 Definitions 128 8.3 Safety Aspects 130 8,4 Experiences and Experimental Results 132 8.5 Conclusions 135 9. FINAL STORAGE 137 9.1 General 137 9.2 Options in Various Countries 138 9.3 depository for Low- and Intermediate-level Wastes in Sweden (ALMA) 9.3.1 Conceptual design and costs 141 9.3.2 Waste products and amounts 9.3.3 Transport system 9.4 (..inclusions 145 IV 10. THE LONG-TERM BEHAVIOUR OF BITUMEN-WASTE PRODUCTS 147 10.1 General 147 10.2 Scope 148 10.3 Waste Products and Final Storage Time 149 10.4 Physico-Chemical Long-Term Stability of Bitumen-Waste Products (BWPs) 151 10.4.1 Radiation effects and stability 10.4.2 Thermal effects and stability 10.4.3 Dimensional and mechanical stability 10.4.4 Long-term sedimentation and homogeneity 10.4.5 Chemical stability 10.4.6 Interaction with surrounding storage media 10.4.7 Gas generation and effects 10.4.8 Effects on the leach resistance 10.5 Microbial stability 166 10.6 Other Long-Term Aspects 170 10.6.1 Criticality risk 10.6.2 Helium generation 10.6.3 Energy storage 10.7 Conclusions 173 ACKNOWLEDGEMENTS REFERENCES (R-series; other references in Part II) PART II BIBLIOGRAPHY OF THE BITUMINIZATION OF RADIOACTIVE WASTES ANNEXES LIST OF TABLES TABLE I Bituminous substances and some of their charac- teristics TABLE II : Resistance of bitumen to the effects of chemicals at room temperature TABLE III : Chemical resistance of bitumen TABLE IV : Equiviscous temperatures /'C/ TABLE V : Conversion factors for viscosities TABLE VI : Specific density of bitumens TABLE VII : Specific density of bitumens from heavily cracked residues TABLE VIII : Specific heat of bitumen TABLE IX : Surface tension of bitumens TABLE X : Dielectric loss TABLE XI : Dielectric loss TABLE XII : Physical data on bitumen TABLE XIII : Approximate annual "wet" waste production by a 900 MWe-BWR TABLE XIV : Approximate annual "wet" waste production by a 900 MWe-PWR TABLE XV : Approximate annual volumes of solid radioactive wastes from a 1000 MWe-LWR TABLE XVI : Wastes from two 590 MWe-BWRs conditioned by bituminization at Barsebäck TABLE XVII : Corrosion and fission products in the primary water TABLE XVIII: Distribution of radionuclides [%) in an evaporation concentrate of a 670 MWe-BWR TABLE XIX : Origin of the various categories of waste (from reprocessing) TABLE XX : Approximate specific waste production of the various waste types TABLE XXI : Estimated composition of liquid ILW after evapora- tion TABLE XXII: Important properties of bitumen-waste mixtures 1n the various waste management phases VI TABLE XXIII: Sow properties of "typical" LUR waste-bituaen Mixtures TABLE XXIV : Sow properties of "typical" intermediate-level reprocessing waste-bituMen Mixtures TABLE XXV : Probable composition of ground-water in crystalline rock at great depth TABLE XXVI : Conposition of a natural water before and after contact with concrete VII LIST OF FIGURES Fig. 1 : Typical temperature/viscosity chart for bitumens Fig. 2 : drum for bitumen-waste product Fig. 3 : Cooling curves of bitumen-waste products Fig. 4 : Flowsheet of the bituminization at the Barsebäck nuclear power station Fig. 5 : System for processing radioactive waste at the Barsebäck nuclear power station Fig. 6 a : Drum transfer system and interim storage facility at Barsebäck Fig. 6 b : Lead bell for the transfer of product drums Fig. 7 : Liquid waste treatment system at the Forsmark Nuclear Power Station Fig. 8 : Bituminization installation at the Karlsruhe Nuclear Research Center /I79/ Fig. 9 : Functional flowsheet of Eurochemic's ILW bituminization process Fig. 10 : Bituminization plant of Eurochemic Fiq. 11 : Bituminization facility at the Risö Research Fstablishment /I15/ Fig. I? : curocJiciiiic'a interim storage facility for solid and solidified intermediate-level radioactive wastes Fig. 13 : Interim storage of radioactive waste-bitumen products in a concrete bunker Fig. 14 : The "ALMA" waste packages and transport system /R-28/ Fig. 15 : A design proposal for a geologic repository for LLW and ILW (ALMA) /R-28/ PART I PROPERTIES A» LONG-TERK BEHAVIOUR OF BITUMEN AND RADIOACTIVE MASTE-BITUMEN MIXTURES PART 1 PROPERTIES AND LONG-TERM BEHAVIOUR OF BITUMEN AND RADIOACTIVE WASTE-BITUMEN MIXTURES SUMMARY AND CONCLUSIONS This report deals with the properties and 7on?-ter» behaviour of bitumens of importance for their use in the conditioning of racic- active wastes and reviews the present knowledge on the properties of waste-bitumen mixtures obtained by the bituminiza+ion of reactor and fuel reprocessing wastes.