Change search
Link to record
Permanent link

Direct link
BETA
Publications (10 of 147) Show all publications
Pusch, R., Weston, R. & Kasbohm, J. (2020). Deep Boreholes for Storage of Spent Reactor Fuel and Use of the Heated Rock for Production of Electric Energy or hot fluid for heating purposes. Earth Sciences and Geotechnical Engineering, 10(1), 127-153
Open this publication in new window or tab >>Deep Boreholes for Storage of Spent Reactor Fuel and Use of the Heated Rock for Production of Electric Energy or hot fluid for heating purposes
2020 (English)In: Earth Sciences and Geotechnical Engineering, ISSN 1792-9040, Vol. 10, no 1, p. 127-153Article in journal (Refereed) Published
Abstract [en]

Lack of energy is a serious threat to the prosperity of many developed states that have access to or plan to use nuclear power. The paper describes a concept for solving two major problems related to these conditions, namely safe disposal of spent reactor fuel and generation of electric energy or hot fluid by use of heat produced by the disposed waste. The challenge in storing spent nuclear fuel can be met with by installing such highly radioactive waste in deep boreholes with fuel rods encapsulated in canisters of copper-lined iron or titanium. Electric energy can be generated by utilizing the accumulated heat in the same rock mass by pumping up hot water or clayey mud from series of deep holes bored parallel and between corresponding holes with nuclear waste. The amounts of heat in each of the hot-water holes overlap and raise the initial rock temperature at 1,500-3,000 m depth to about 80-90oC after some 50 years and to 70-80oC in 500 years, after which the temperature in the hot-fluid holes goes down successively to the initial value 60-70oC in about 500 years. If these holes are subsequently deepened from 3,000 to 5,000 meters, utilization of the hot fluid can continue for another 500 years.

Place, publisher, year, edition, pages
UK: Scientific Press International Limited, 2020
Keywords
Deep boreholes, highly radioactive waste, high level radioactive waste (HLW), spent reactor fuel, smectite, clays
National Category
Geotechnical Engineering
Research subject
Soil Mechanics
Identifiers
urn:nbn:se:ltu:diva-77273 (URN)
Note

Validerad;2020;Nivå 1;2020-01-07 (johcin)

Available from: 2020-01-01 Created: 2020-01-01 Last updated: 2020-01-07Bibliographically approved
Bouchelaghem, F. & Pusch, R. (2020). Diffusion calculations on numerical images of bentonite microstructure. Applied Clay Science
Open this publication in new window or tab >>Diffusion calculations on numerical images of bentonite microstructure
2020 (English)In: Applied Clay Science, ISSN 0169-1317, E-ISSN 1872-9053Article in journal (Refereed) Submitted
Abstract [en]

Effective diffusion tensors were computed for tracer diffusion through compacted water-saturated bentonite at two distinct scales by combining random microstructures and microstructures obtained by Transmission Electron Microscopy. The original micrographs have been thresholded by considering four distinct phases at the mesoscopic scale, and image analysis techniques have been employed in order to characterize the morphology and in particular the texture anisotropy of grains, clay gels and macrovoids. The Homogenization of Periodic Media approach employed is based on the local description ion diffusion at both the microscopic level of clay platelets (assuming variable diffusivity and ion sorption) and the mesoscopic level of clay aggregates and macropores. The local problems were successively solved using randon and TEM-based numerical microstructures in order to investigate the contribution to macroscopic diffusion of soft gels, dense gels and macrovoids under various configurations. Comparisons were made with existing diffusion data for montmorillonite and natural bentonite, and a particular attention was given to the anisotropy of the macroscopic diffusion tensor in connection with morphological characteristics of the underlying microstructure. The effect of clay matrix diffusivity on the magnitude and orientation of the macroscopic diffusion tensor has been investigated, and the principal axes of diffusion have been compared with the index of fabric orientation. Computations were also performed on microstructures of increasing size in order to investigate the model implicit assumption of existence of a Representative Elementary Volume.

Place, publisher, year, edition, pages
Elsevier, 2020
Keywords
Ion diffusion, Compacted saturated bentonite, Image analysis, Numerical Homogenization, Finite Element computations, Effective diffusion tensor, Experimental comparison, Anisotropy
National Category
Geotechnical Engineering
Research subject
Soil Mechanics
Identifiers
urn:nbn:se:ltu:diva-78378 (URN)
Available from: 2020-04-07 Created: 2020-04-07 Last updated: 2020-04-07
Pusch, R., Kasbohm, J. & Hoang-Minh, T. (2019). Degradation Mechanisms in Smectitic Clay for Isolating Radioactive Waste. Journal of Earth Sciences and Geotechnical Engineering, 9(3), 115-130
Open this publication in new window or tab >>Degradation Mechanisms in Smectitic Clay for Isolating Radioactive Waste
2019 (English)In: Journal of Earth Sciences and Geotechnical Engineering, ISSN 1792-9040, E-ISSN 1792-9660, Vol. 9, no 3, p. 115-130Article in journal (Refereed) Published
Abstract [en]

Most of the proposed techniques for chemical shielding of radioactive waste implies use of smectite clay, which degrades according to a well-known scheme. Since such “buffer” clay has to serve for many thousands of years, the mechanisms in the unavoidable long-term degradation process must be understood and accounted for as described in the paper. In addition to conversion of smectite to non-expandable minerals cementation by precipitation of siliceous matter created in the degradation process is of concern since it can reduce the self-sealing capacity of desiccated or mechanically damaged clay.

Place, publisher, year, edition, pages
UK: Scientific Press International Limited, 2019
Keywords
Smectite clays, diffractogram, radioactive wastes, montmorillonite, XRD, TEM, Holmehus clay
National Category
Engineering and Technology Geotechnical Engineering
Research subject
Soil Mechanics
Identifiers
urn:nbn:se:ltu:diva-75708 (URN)
Note

Validerad;2019;Nivå 1;2019-09-02 (johcin)

Available from: 2019-08-27 Created: 2019-08-27 Last updated: 2019-09-02Bibliographically approved
Pusch, R., Kasbohm, J., Knutsson, S., Hoang-Minh, T. & Nguyen-Thanh, L. (2019). Disposal of Low- and Intermediate-Level Radioactive Waste. Journal of Earth Sciences and Geotechnical Engineering, 9(3), 237-272
Open this publication in new window or tab >>Disposal of Low- and Intermediate-Level Radioactive Waste
Show others...
2019 (English)In: Journal of Earth Sciences and Geotechnical Engineering, ISSN 1792-9040, E-ISSN 1792-9660, Vol. 9, no 3, p. 237-272Article in journal (Refereed) Published
Abstract [en]

As for isolation of high-level radioactive waste by use of smectite clay it serves very well also for hindering radionuclides from low- and intermediate-level waste to contaminate groundwater. It can be used for minimizing groundwater flow through and along waste packages and for providing them with ductile embedment for eliminating the risk of damage caused by displacements in host rock or concrete vaults. The clay can have the form of liners placed and compacted on site over vaults constructed on the ground surface, or consist of compacted blocks of clay granules that are tightly placed around waste packages in underground drifts and rooms. In either case the initially incompletely water saturated clay will swell in conjunction with water uptake until tight contact with the confining medium has been established. The clay seals must be sufficiently dense to fulfill criteria set with respect to hydraulic conductivity and swelling capacity, paying due attention to the salt content in the porewater. Their physical and chemical stabilities must be acceptable in short- and long-term perspectives, which is a few hundred years for most low-level wastes up to tens of thousands of years for long-lived waste. 

Place, publisher, year, edition, pages
UK: Scientific Press International Limited, 2019
Keywords
Low-level radioactive waste (LLW), smectite clay, radionuclides, underground disposal of radioactive waste, mineralogy of clays
National Category
Engineering and Technology Geotechnical Engineering
Research subject
Soil Mechanics
Identifiers
urn:nbn:se:ltu:diva-75712 (URN)
Note

Validerad;2019;Nivå 1;2019-09-02 (johcin)

Available from: 2019-08-27 Created: 2019-08-27 Last updated: 2019-09-02Bibliographically approved
Popov, V., Adey, R., Pusch, R. & Kasbohm, J. (2019). Disposal of Radioactive Waste in Abandoned Mines. Journal of Earth Sciences and Geotechnical Engineering, 9(3), 1-38
Open this publication in new window or tab >>Disposal of Radioactive Waste in Abandoned Mines
2019 (English)In: Journal of Earth Sciences and Geotechnical Engineering, ISSN 1792-9040, E-ISSN 1792-9660, Vol. 9, no 3, p. 1-38Article in journal (Refereed) Published
Abstract [en]

Countries using nuclear energy tend to favour disposal of Low-Level and Intermediate-Level radioactive waste in mined repositories consisting of series of tunnels or drifts connected to disposal tunnels at a few hundred meters depth. Abandoned mines can serve as repositories for such waste and the present study indicates that this would be possible also for High-Level Waste in the form of spent reactor fuel. The technique implies encapsulation of such waste in metal canisters surrounded by densely compacted smectite clay in relatively shallow mined repositories as well as in very deep bored holes. Intermediate-Level radioactive waste can be disposed of in caverns in the form of packages of metal containers cast in low-pH concrete and embedded in dense smectitic clay.

Place, publisher, year, edition, pages
UK: Scientific Press International Limited, 2019
Keywords
Low-Level and Intermediate-Level radioactive waste (LLW and ILW), smectite clay, compaction, excavation disturbed zone (EDZ), crystalline rock, numerical modelling.
National Category
Engineering and Technology Geotechnical Engineering
Research subject
Soil Mechanics
Identifiers
urn:nbn:se:ltu:diva-75705 (URN)
Note

Validerad;2019;Nivå 1;2019-09-02 (johcin)

Available from: 2019-08-27 Created: 2019-08-27 Last updated: 2019-09-02Bibliographically approved
Chabuk, A., Al-Ansari, N., Hussain, H. M., Laue, J., Hazim, A., Knutsson, S. & Pusch, R. (2019). Landfill Sites Selection Using MCDM and Comparing Method of Change Detection for Babylon Governorate, Iraq. Environmental Science and Pollution Research, 26(35), 35325-35339
Open this publication in new window or tab >>Landfill Sites Selection Using MCDM and Comparing Method of Change Detection for Babylon Governorate, Iraq
Show others...
2019 (English)In: Environmental Science and Pollution Research, ISSN 0944-1344, E-ISSN 1614-7499, Vol. 26, no 35, p. 35325-35339Article in journal (Refereed) Published
Abstract [en]

Landfill site`s selection represents a complicated process due to the large number of variables to be adopted. In this study, an arid area (Babylon Governorate as a case study) was selected. It is located in the middle region of Iraq. In this area, the  landfills do not satisfy the required  international criteria.  Fifteen  of the  most significant criterion were selected for this purpose. For suitable weight for each criterion, the multi criteria decision making (MCDM) methods were applied. These methods are AHP and RSW. In the GIS software 10.5, the raster maps of the chosen criterion were arranged and analysed. The method of change detection was implemented to determine the matching pixels and non-matching pixels. The final results showed that there are two candidate locations for landfills for each district in the governorate (ten sites). The areas of the selected sites were sufficient to contain the cumulative quantity of solid waste from 2020 until 2030.

Place, publisher, year, edition, pages
Springer, 2019
Keywords
MCDM, Change Detection, RSW, AHP, Landfill siting
National Category
Geotechnical Engineering
Research subject
Soil Mechanics
Identifiers
urn:nbn:se:ltu:diva-73400 (URN)10.1007/s11356-019-05064-7 (DOI)000507276300005 ()31044377 (PubMedID)2-s2.0-85065255296 (Scopus ID)
Note

Validerad;2020;Nivå 2;2020-01-03 (johcin)

Available from: 2019-04-03 Created: 2019-04-03 Last updated: 2020-06-05Bibliographically approved
Nakano, M., Yong, R. N. & Pusch, R. (2019). Mathematical Method Re-examined for Assessment of Ground Contaminated by Radioactive-Contaminated Groundwater. Journal of Earth Sciences and Geotechnical Engineering, 9(3), 227-235
Open this publication in new window or tab >>Mathematical Method Re-examined for Assessment of Ground Contaminated by Radioactive-Contaminated Groundwater
2019 (English)In: Journal of Earth Sciences and Geotechnical Engineering, ISSN 1792-9040, E-ISSN 1792-9660, Vol. 9, no 3, p. 227-235Article in journal (Refereed) Published
Abstract [en]

In this paper we re-examined the transfer equation of radioactive substances in the ground and offer a more realistic transfer equation and other equations available for assessment of the ground contamination from radioactive-contaminated groundwater. The transfer equation takes into account kinematic and hydrodynamic considerations on mass conservation of mobile radioactive substances in a porous medium that typifies the ground. The other equations available for contamination assessment are concerned with deposition in contaminated areas and discharge flow of contaminants to the areas contiguous to contaminated area. The equations are derived on the understanding that disintegration of the radioactive substances adhering onto solids in the ground porous medium occurs as a sink term during the transfer of mobile radioactive substances. Finally, it is noted that the discharge of groundwater due to advective flow will be predominant in comparison to the discharge by diffusion

Place, publisher, year, edition, pages
UK: Scientific Press International Limited, 2019
Keywords
Radioactive contamination, Transfer equation, Deposition, Assessment, Discharge, Groundwater
National Category
Engineering and Technology Geotechnical Engineering
Research subject
Soil Mechanics
Identifiers
urn:nbn:se:ltu:diva-75711 (URN)
Note

Validerad;2019;Nivå 1;2019-09-02 (johcin)

Available from: 2019-08-27 Created: 2019-08-27 Last updated: 2019-09-02Bibliographically approved
Pusch, R., Kasbohm, J., Hoang-Minh, T. & Nguyen-Thanh, L. (2019). Mechanisms Involved in Maturation of Clay Seals in Boreholes for Storing Spent Reactor Fuel. Journal of Earth Sciences and Geotechnical Engineering, 9(3), 197-226
Open this publication in new window or tab >>Mechanisms Involved in Maturation of Clay Seals in Boreholes for Storing Spent Reactor Fuel
2019 (English)In: Journal of Earth Sciences and Geotechnical Engineering, ISSN 1792-9040, E-ISSN 1792-9660, Vol. 9, no 3, p. 197-226Article in journal (Refereed) Published
Abstract [en]

Smectite clay, especially montmorillonite, is proposed for isolating canisters containing highly radioactive waste (HLW) like spent reactor fuel placed in deep boreholes. It is used for minimizing groundwater flow around and along waste packages (“Buffer Clay”) and for providing them with ductile embedment for eliminating risk of canister damage caused by displacements in the host rock. The clay has the form of heavily compacted blocks of granules that swell in conjunction with water uptake until their full hydration potential has been utilized. The dense clay blocks are fitted in perforated supercontainers that are submerged in smectite mud. The long-term chemical stability of the clay is sufficient for providing the required waste-isolating capacity, which is primarily supplied by the heavyness of stagnant, very salt groundwater at depth.

Place, publisher, year, edition, pages
UK: Scientific Press International Limited, 2019
Keywords
Smectite clay, montmorillonite, isolating canisters, highly radioactive waste (HLW), supercontainers, dry density, settlement, creep settlement, microstructure of smectite clay
National Category
Engineering and Technology Geotechnical Engineering
Research subject
Soil Mechanics
Identifiers
urn:nbn:se:ltu:diva-75710 (URN)
Note

Validerad;2019;Nivå 1;2019-09-02 (johcin)

Available from: 2019-08-27 Created: 2019-08-27 Last updated: 2019-09-02Bibliographically approved
Pusch, R. & Popov, V. (2019). Micro- and macroscopic ion diffusion controlled by clay micro-structure. Journal of Earth Sciences and Geotechnical Engineering, 9(3), 99-114
Open this publication in new window or tab >>Micro- and macroscopic ion diffusion controlled by clay micro-structure
2019 (English)In: Journal of Earth Sciences and Geotechnical Engineering, ISSN 1792-9040, E-ISSN 1792-9660, Vol. 9, no 3, p. 99-114Article in journal (Refereed) Published
Abstract [en]

Very dense smectite clay surrounding canisters with high-level radioactive waste effectively stops migration of radionuclides due to flowing porewater, however, does not stop their movement by diffusion. The paper explains how the diffusion rate of released waste ions depends on the microstructural constitution referring to the mechanisms in diffusive transport and the sorption by the clay matrix of varying density. In general, diffusion refers to the transport of elements by action of random motions and works to eliminate distinct discontinuities in concentration. For smectite clay this process is complex since interlamellar diffusion is a 2-dimensional process on the microscale and takes place in diffuse electrical double-layers on the basal planes of the clay crystallites. This is in contrast with pore diffusion which is a 3-dimensional process. By making use of microstructural parameters one can distinguish the different contributions to bulk diffusion migration and create a basis for theoretical modelling of diffusive ion migration.  

Place, publisher, year, edition, pages
UK: Scientific Press International Limited, 2019
Keywords
Smectite clay, canisters, diffusion, montmorillonite, ion migration, clay microstructure
National Category
Engineering and Technology Geotechnical Engineering
Research subject
Soil Mechanics
Identifiers
urn:nbn:se:ltu:diva-75707 (URN)
Note

Validerad;2019;Nivå 1;2019-09-02 (johcin)

Available from: 2019-08-27 Created: 2019-08-27 Last updated: 2019-09-02Bibliographically approved
Pusch, R. (2019). Microstructure controls physical properties of smectite clay. Journal of Earth Sciences and Geotechnical Engineering, 9(3), 63-98
Open this publication in new window or tab >>Microstructure controls physical properties of smectite clay
2019 (English)In: Journal of Earth Sciences and Geotechnical Engineering, ISSN 1792-9040, E-ISSN 1792-9660, Vol. 9, no 3, p. 63-98Article in journal (Refereed) Published
Abstract [en]

Environmental protection by isolation of radionuclides escaped from High-Level Radioactive Waste stored underground in crystalline rock can be achieved by surrounding the metal canisters by smectite clay, which provides hindrance of radionuclides to migrate into the surroundings, and ductile embedment of them for absorbing seismic and tectonic displacements in the host rock. The waste-isolating capacity of the expansive clay is explained by its high hydrophilic capacity and large specific surface area giving low porosity and limited interconnectivity of the voids, which both makes such clay low-permeable and gives it a very low through-diffusion rate of anionic species like iodine, and of some cationic radionuclides. The expandability of such clay means that it can swell and undergo self-healing in case of microstructural contraction caused by heating. The mechanisms involved in permeation and ion exchange are described based on conceptual microstructural models and their theoretical analogies. Stress/strain phenomena involved in saturation with fluids, desiccation, shearing under deviatoric conditions, and creep strain under stable conditions or at failure are described as well. Longevity matters, which have been richly treated in the literature, is given limited space. 

Place, publisher, year, edition, pages
UK: Scientific Press International Limited, 2019
Keywords
Smectite clay, montmorillonite, microscopy, clay microstructure
National Category
Engineering and Technology Geotechnical Engineering
Research subject
Soil Mechanics
Identifiers
urn:nbn:se:ltu:diva-75706 (URN)
Note

Validerad;2019;Nivå 1;2019-09-02 (johcin)

Available from: 2019-08-27 Created: 2019-08-27 Last updated: 2019-09-02Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0002-6851-4839

Search in DiVA

Show all publications