Decommissioning of Spent Nuclear Fuel Ponds University of Leeds Student Sustainability Research Conference 2019, Leeds, UK. Alexander P. G. Lockwood,

Decommissioning of Spent Nuclear Fuel Ponds University of Leeds Student Sustainability Research Conference 2019, Leeds, UK. Alexander P. G. Lockwood, BEng Supervisors: Dr Timothy Hunter, Dr David Harbottle, Dr Nicholas Warren, Prof Jeffrey Peakall, Martyn Barnes and Prof Geoff Randall

Introduction to the UK nuclear fuel cycle
Presentation Outline Introduction to the UK nuclear fuel cycle Current state of storage ponds and current strategies Application of Dissolved Air Floatation (DAF) Research Conclusions Future work FISSION PRODUCTS Some are stable, some short, medium and long half-lives Some are important radiologically eg I-131, Cs-137 Some are important as neutron poisons eg Xe-135, Sm-149 Some are gaseous and build-up in the fuel matrix causing swelling and may be released into the fuel rod Strong source of alpha, bets and gamma activity in irradiated fuel Strong heat source in fuel - FP decay heating is the principal safety consideration in-reactor The fission products include ones which are stable, ones with very short half-lives of seconds or less, ones with short half-lives of minutes to hours, ones with longer half-lives varying from a few years to hundreds of thousands of years. The most significant ones radiologically are those with medium half-lives such as 131I and 137Cs which have high activities, which are gaseous and therefore mobile. 131I has a half-life of 8 days and is therefore important in the short term after a release. 137Cs is more persistent, with a 30 year half-life. The mix of fission products in a contaminated sample allows its source to be pinned down, whether it is from a recently operating reactor or one which released the fission products some time previously, according to the presence or otherwise of short lived fission products. MINOR ACTINIDES The actinides are all those nuclides from actinium (89) and upwards in the Periodic Table. Apart from uranium (and possibly thorium is a thorium fuelled reactor), they are all generated from neutron captures and/or decays. They tend to be long lived and alpha-unstable and are important contributors to radionuclide toxicity is released to the environment. TRANSURANICS U & Pu classified separately All others (Th, Pa, Np, Am, Cm etc classed as Minor Actinides (MAs))

Magnox Reactors FISSION PRODUCTS MINOR ACTINIDES TRANSURANICS
Some are stable, some short, medium and long half-lives Some are important radiologically eg I-131, Cs-137 Some are important as neutron poisons eg Xe-135, Sm-149 Some are gaseous and build-up in the fuel matrix causing swelling and may be released into the fuel rod Strong source of alpha, bets and gamma activity in irradiated fuel Strong heat source in fuel - FP decay heating is the principal safety consideration in-reactor The fission products include ones which are stable, ones with very short half-lives of seconds or less, ones with short half-lives of minutes to hours, ones with longer half-lives varying from a few years to hundreds of thousands of years. The most significant ones radiologically are those with medium half-lives such as 131I and 137Cs which have high activities, which are gaseous and therefore mobile. 131I has a half-life of 8 days and is therefore important in the short term after a release. 137Cs is more persistent, with a 30 year half-life. The mix of fission products in a contaminated sample allows its source to be pinned down, whether it is from a recently operating reactor or one which released the fission products some time previously, according to the presence or otherwise of short lived fission products. MINOR ACTINIDES The actinides are all those nuclides from actinium (89) and upwards in the Periodic Table. Apart from uranium (and possibly thorium is a thorium fuelled reactor), they are all generated from neutron captures and/or decays. They tend to be long lived and alpha-unstable and are important contributors to radionuclide toxicity is released to the environment. TRANSURANICS U & Pu classified separately All others (Th, Pa, Np, Am, Cm etc classed as Minor Actinides (MAs))

Designed for optimum plutonium production as well as civil use
Magnox Reactors Gas cooled (CO2) Metallic Uranium fuel Magnox Fuel cladding Designed for optimum plutonium production as well as civil use In service till 2015 26 in the UK FISSION PRODUCTS Some are stable, some short, medium and long half-lives Some are important radiologically eg I-131, Cs-137 Some are important as neutron poisons eg Xe-135, Sm-149 Some are gaseous and build-up in the fuel matrix causing swelling and may be released into the fuel rod Strong source of alpha, bets and gamma activity in irradiated fuel Strong heat source in fuel - FP decay heating is the principal safety consideration in-reactor The fission products include ones which are stable, ones with very short half-lives of seconds or less, ones with short half-lives of minutes to hours, ones with longer half-lives varying from a few years to hundreds of thousands of years. The most significant ones radiologically are those with medium half-lives such as 131I and 137Cs which have high activities, which are gaseous and therefore mobile. 131I has a half-life of 8 days and is therefore important in the short term after a release. 137Cs is more persistent, with a 30 year half-life. The mix of fission products in a contaminated sample allows its source to be pinned down, whether it is from a recently operating reactor or one which released the fission products some time previously, according to the presence or otherwise of short lived fission products. MINOR ACTINIDES The actinides are all those nuclides from actinium (89) and upwards in the Periodic Table. Apart from uranium (and possibly thorium is a thorium fuelled reactor), they are all generated from neutron captures and/or decays. They tend to be long lived and alpha-unstable and are important contributors to radionuclide toxicity is released to the environment. TRANSURANICS U & Pu classified separately All others (Th, Pa, Np, Am, Cm etc classed as Minor Actinides (MAs))

Reactor FISSION PRODUCTS MINOR ACTINIDES TRANSURANICS

Reactor Magnox Skip Uranium metal fuel pellet Cladding
FISSION PRODUCTS Some are stable, some short, medium and long half-lives Some are important radiologically eg I-131, Cs-137 Some are important as neutron poisons eg Xe-135, Sm-149 Some are gaseous and build-up in the fuel matrix causing swelling and may be released into the fuel rod Strong source of alpha, bets and gamma activity in irradiated fuel Strong heat source in fuel - FP decay heating is the principal safety consideration in-reactor The fission products include ones which are stable, ones with very short half-lives of seconds or less, ones with short half-lives of minutes to hours, ones with longer half-lives varying from a few years to hundreds of thousands of years. The most significant ones radiologically are those with medium half-lives such as 131I and 137Cs which have high activities, which are gaseous and therefore mobile. 131I has a half-life of 8 days and is therefore important in the short term after a release. 137Cs is more persistent, with a 30 year half-life. The mix of fission products in a contaminated sample allows its source to be pinned down, whether it is from a recently operating reactor or one which released the fission products some time previously, according to the presence or otherwise of short lived fission products. MINOR ACTINIDES The actinides are all those nuclides from actinium (89) and upwards in the Periodic Table. Apart from uranium (and possibly thorium is a thorium fuelled reactor), they are all generated from neutron captures and/or decays. They tend to be long lived and alpha-unstable and are important contributors to radionuclide toxicity is released to the environment. TRANSURANICS U & Pu classified separately All others (Th, Pa, Np, Am, Cm etc classed as Minor Actinides (MAs)) Cooling fins

Shielded Transport Flask
Magnox Sellafield Shielded Transport Flask Magnox Skip Reactor Uranium metal fuel pellet Cladding FISSION PRODUCTS Some are stable, some short, medium and long half-lives Some are important radiologically eg I-131, Cs-137 Some are important as neutron poisons eg Xe-135, Sm-149 Some are gaseous and build-up in the fuel matrix causing swelling and may be released into the fuel rod Strong source of alpha, bets and gamma activity in irradiated fuel Strong heat source in fuel - FP decay heating is the principal safety consideration in-reactor The fission products include ones which are stable, ones with very short half-lives of seconds or less, ones with short half-lives of minutes to hours, ones with longer half-lives varying from a few years to hundreds of thousands of years. The most significant ones radiologically are those with medium half-lives such as 131I and 137Cs which have high activities, which are gaseous and therefore mobile. 131I has a half-life of 8 days and is therefore important in the short term after a release. 137Cs is more persistent, with a 30 year half-life. The mix of fission products in a contaminated sample allows its source to be pinned down, whether it is from a recently operating reactor or one which released the fission products some time previously, according to the presence or otherwise of short lived fission products. MINOR ACTINIDES The actinides are all those nuclides from actinium (89) and upwards in the Periodic Table. Apart from uranium (and possibly thorium is a thorium fuelled reactor), they are all generated from neutron captures and/or decays. They tend to be long lived and alpha-unstable and are important contributors to radionuclide toxicity is released to the environment. TRANSURANICS U & Pu classified separately All others (Th, Pa, Np, Am, Cm etc classed as Minor Actinides (MAs)) Cooling fins

Magnox Sellafield Shielded Transport Flask Magnox Skip Reactor Uranium metal fuel pellet Cladding Magnox Skip Storage Pond FISSION PRODUCTS Some are stable, some short, medium and long half-lives Some are important radiologically eg I-131, Cs-137 Some are important as neutron poisons eg Xe-135, Sm-149 Some are gaseous and build-up in the fuel matrix causing swelling and may be released into the fuel rod Strong source of alpha, bets and gamma activity in irradiated fuel Strong heat source in fuel - FP decay heating is the principal safety consideration in-reactor The fission products include ones which are stable, ones with very short half-lives of seconds or less, ones with short half-lives of minutes to hours, ones with longer half-lives varying from a few years to hundreds of thousands of years. The most significant ones radiologically are those with medium half-lives such as 131I and 137Cs which have high activities, which are gaseous and therefore mobile. 131I has a half-life of 8 days and is therefore important in the short term after a release. 137Cs is more persistent, with a 30 year half-life. The mix of fission products in a contaminated sample allows its source to be pinned down, whether it is from a recently operating reactor or one which released the fission products some time previously, according to the presence or otherwise of short lived fission products. MINOR ACTINIDES The actinides are all those nuclides from actinium (89) and upwards in the Periodic Table. Apart from uranium (and possibly thorium is a thorium fuelled reactor), they are all generated from neutron captures and/or decays. They tend to be long lived and alpha-unstable and are important contributors to radionuclide toxicity is released to the environment. TRANSURANICS U & Pu classified separately All others (Th, Pa, Np, Am, Cm etc classed as Minor Actinides (MAs)) Cooling fins

Magnox Sellafield Shielded Transport Flask Magnox Skip Reactor Uranium metal fuel pellet Cladding Magnox Skip Storage Pond FISSION PRODUCTS Some are stable, some short, medium and long half-lives Some are important radiologically eg I-131, Cs-137 Some are important as neutron poisons eg Xe-135, Sm-149 Some are gaseous and build-up in the fuel matrix causing swelling and may be released into the fuel rod Strong source of alpha, bets and gamma activity in irradiated fuel Strong heat source in fuel - FP decay heating is the principal safety consideration in-reactor The fission products include ones which are stable, ones with very short half-lives of seconds or less, ones with short half-lives of minutes to hours, ones with longer half-lives varying from a few years to hundreds of thousands of years. The most significant ones radiologically are those with medium half-lives such as 131I and 137Cs which have high activities, which are gaseous and therefore mobile. 131I has a half-life of 8 days and is therefore important in the short term after a release. 137Cs is more persistent, with a 30 year half-life. The mix of fission products in a contaminated sample allows its source to be pinned down, whether it is from a recently operating reactor or one which released the fission products some time previously, according to the presence or otherwise of short lived fission products. MINOR ACTINIDES The actinides are all those nuclides from actinium (89) and upwards in the Periodic Table. Apart from uranium (and possibly thorium is a thorium fuelled reactor), they are all generated from neutron captures and/or decays. They tend to be long lived and alpha-unstable and are important contributors to radionuclide toxicity is released to the environment. TRANSURANICS U & Pu classified separately All others (Th, Pa, Np, Am, Cm etc classed as Minor Actinides (MAs)) Decanner Cooling fins

Magnox Sellafield Shielded Transport Flask Magnox Skip Reactor Uranium metal fuel pellet Cladding Clad Silo Magnox Skip Storage Pond FISSION PRODUCTS Some are stable, some short, medium and long half-lives Some are important radiologically eg I-131, Cs-137 Some are important as neutron poisons eg Xe-135, Sm-149 Some are gaseous and build-up in the fuel matrix causing swelling and may be released into the fuel rod Strong source of alpha, bets and gamma activity in irradiated fuel Strong heat source in fuel - FP decay heating is the principal safety consideration in-reactor The fission products include ones which are stable, ones with very short half-lives of seconds or less, ones with short half-lives of minutes to hours, ones with longer half-lives varying from a few years to hundreds of thousands of years. The most significant ones radiologically are those with medium half-lives such as 131I and 137Cs which have high activities, which are gaseous and therefore mobile. 131I has a half-life of 8 days and is therefore important in the short term after a release. 137Cs is more persistent, with a 30 year half-life. The mix of fission products in a contaminated sample allows its source to be pinned down, whether it is from a recently operating reactor or one which released the fission products some time previously, according to the presence or otherwise of short lived fission products. MINOR ACTINIDES The actinides are all those nuclides from actinium (89) and upwards in the Periodic Table. Apart from uranium (and possibly thorium is a thorium fuelled reactor), they are all generated from neutron captures and/or decays. They tend to be long lived and alpha-unstable and are important contributors to radionuclide toxicity is released to the environment. TRANSURANICS U & Pu classified separately All others (Th, Pa, Np, Am, Cm etc classed as Minor Actinides (MAs)) Decanner Cooling fins

Magnox Sellafield Shielded Transport Flask Magnox Skip Reactor Uranium metal fuel pellet Cladding Clad Silo Magnox Skip Storage Pond FISSION PRODUCTS Some are stable, some short, medium and long half-lives Some are important radiologically eg I-131, Cs-137 Some are important as neutron poisons eg Xe-135, Sm-149 Some are gaseous and build-up in the fuel matrix causing swelling and may be released into the fuel rod Strong source of alpha, bets and gamma activity in irradiated fuel Strong heat source in fuel - FP decay heating is the principal safety consideration in-reactor The fission products include ones which are stable, ones with very short half-lives of seconds or less, ones with short half-lives of minutes to hours, ones with longer half-lives varying from a few years to hundreds of thousands of years. The most significant ones radiologically are those with medium half-lives such as 131I and 137Cs which have high activities, which are gaseous and therefore mobile. 131I has a half-life of 8 days and is therefore important in the short term after a release. 137Cs is more persistent, with a 30 year half-life. The mix of fission products in a contaminated sample allows its source to be pinned down, whether it is from a recently operating reactor or one which released the fission products some time previously, according to the presence or otherwise of short lived fission products. MINOR ACTINIDES The actinides are all those nuclides from actinium (89) and upwards in the Periodic Table. Apart from uranium (and possibly thorium is a thorium fuelled reactor), they are all generated from neutron captures and/or decays. They tend to be long lived and alpha-unstable and are important contributors to radionuclide toxicity is released to the environment. TRANSURANICS U & Pu classified separately All others (Th, Pa, Np, Am, Cm etc classed as Minor Actinides (MAs)) Decanner Cooling fins Reprocessing U & Pu HAL

FISSION PRODUCTS MINOR ACTINIDES TRANSURANICS

Liquid effluent route FISSION PRODUCTS MINOR ACTINIDES TRANSURANICS

FISSION PRODUCTS MINOR ACTINIDES TRANSURANICS

Site Ion eXchange Effluent Plant
FISSION PRODUCTS Some are stable, some short, medium and long half-lives Some are important radiologically eg I-131, Cs-137 Some are important as neutron poisons eg Xe-135, Sm-149 Some are gaseous and build-up in the fuel matrix causing swelling and may be released into the fuel rod Strong source of alpha, bets and gamma activity in irradiated fuel Strong heat source in fuel - FP decay heating is the principal safety consideration in-reactor The fission products include ones which are stable, ones with very short half-lives of seconds or less, ones with short half-lives of minutes to hours, ones with longer half-lives varying from a few years to hundreds of thousands of years. The most significant ones radiologically are those with medium half-lives such as 131I and 137Cs which have high activities, which are gaseous and therefore mobile. 131I has a half-life of 8 days and is therefore important in the short term after a release. 137Cs is more persistent, with a 30 year half-life. The mix of fission products in a contaminated sample allows its source to be pinned down, whether it is from a recently operating reactor or one which released the fission products some time previously, according to the presence or otherwise of short lived fission products. MINOR ACTINIDES The actinides are all those nuclides from actinium (89) and upwards in the Periodic Table. Apart from uranium (and possibly thorium is a thorium fuelled reactor), they are all generated from neutron captures and/or decays. They tend to be long lived and alpha-unstable and are important contributors to radionuclide toxicity is released to the environment. TRANSURANICS U & Pu classified separately All others (Th, Pa, Np, Am, Cm etc classed as Minor Actinides (MAs)) Site Ion eXchange Effluent Plant

Irish Sea Cs137 & Sr90 stripped pH≈7 pH≈11 CO2 Pond and Silo feed
IX bed change BSTs Sampling Discharge Tank Irish Sea FISSION PRODUCTS Some are stable, some short, medium and long half-lives Some are important radiologically eg I-131, Cs-137 Some are important as neutron poisons eg Xe-135, Sm-149 Some are gaseous and build-up in the fuel matrix causing swelling and may be released into the fuel rod Strong source of alpha, bets and gamma activity in irradiated fuel Strong heat source in fuel - FP decay heating is the principal safety consideration in-reactor The fission products include ones which are stable, ones with very short half-lives of seconds or less, ones with short half-lives of minutes to hours, ones with longer half-lives varying from a few years to hundreds of thousands of years. The most significant ones radiologically are those with medium half-lives such as 131I and 137Cs which have high activities, which are gaseous and therefore mobile. 131I has a half-life of 8 days and is therefore important in the short term after a release. 137Cs is more persistent, with a 30 year half-life. The mix of fission products in a contaminated sample allows its source to be pinned down, whether it is from a recently operating reactor or one which released the fission products some time previously, according to the presence or otherwise of short lived fission products. MINOR ACTINIDES The actinides are all those nuclides from actinium (89) and upwards in the Periodic Table. Apart from uranium (and possibly thorium is a thorium fuelled reactor), they are all generated from neutron captures and/or decays. They tend to be long lived and alpha-unstable and are important contributors to radionuclide toxicity is released to the environment. TRANSURANICS U & Pu classified separately All others (Th, Pa, Np, Am, Cm etc classed as Minor Actinides (MAs)) Cs137 & Sr90 stripped Sand Bed Filter Carbonation Tower Ion Exchange Bed Sampling and Discharge to Sea

Mg competition for IX sites
pH≈7 pH≈11 CO2 Pond and Silo feed IX bed change BSTs Sampling Discharge Tank Irish Sea Mg competition for IX sites Increase in bed changes and reduction in storage capacity Mg solubilised FISSION PRODUCTS Some are stable, some short, medium and long half-lives Some are important radiologically eg I-131, Cs-137 Some are important as neutron poisons eg Xe-135, Sm-149 Some are gaseous and build-up in the fuel matrix causing swelling and may be released into the fuel rod Strong source of alpha, bets and gamma activity in irradiated fuel Strong heat source in fuel - FP decay heating is the principal safety consideration in-reactor The fission products include ones which are stable, ones with very short half-lives of seconds or less, ones with short half-lives of minutes to hours, ones with longer half-lives varying from a few years to hundreds of thousands of years. The most significant ones radiologically are those with medium half-lives such as 131I and 137Cs which have high activities, which are gaseous and therefore mobile. 131I has a half-life of 8 days and is therefore important in the short term after a release. 137Cs is more persistent, with a 30 year half-life. The mix of fission products in a contaminated sample allows its source to be pinned down, whether it is from a recently operating reactor or one which released the fission products some time previously, according to the presence or otherwise of short lived fission products. MINOR ACTINIDES The actinides are all those nuclides from actinium (89) and upwards in the Periodic Table. Apart from uranium (and possibly thorium is a thorium fuelled reactor), they are all generated from neutron captures and/or decays. They tend to be long lived and alpha-unstable and are important contributors to radionuclide toxicity is released to the environment. TRANSURANICS U & Pu classified separately All others (Th, Pa, Np, Am, Cm etc classed as Minor Actinides (MAs)) Cs137 & Sr90 stripped Sand Bed Filter Carbonation Tower Ion Exchange Bed Sampling and Discharge to Sea

Solid waste route FISSION PRODUCTS MINOR ACTINIDES TRANSURANICS
Some are stable, some short, medium and long half-lives Some are important radiologically eg I-131, Cs-137 Some are important as neutron poisons eg Xe-135, Sm-149 Some are gaseous and build-up in the fuel matrix causing swelling and may be released into the fuel rod Strong source of alpha, bets and gamma activity in irradiated fuel Strong heat source in fuel - FP decay heating is the principal safety consideration in-reactor The fission products include ones which are stable, ones with very short half-lives of seconds or less, ones with short half-lives of minutes to hours, ones with longer half-lives varying from a few years to hundreds of thousands of years. The most significant ones radiologically are those with medium half-lives such as 131I and 137Cs which have high activities, which are gaseous and therefore mobile. 131I has a half-life of 8 days and is therefore important in the short term after a release. 137Cs is more persistent, with a 30 year half-life. The mix of fission products in a contaminated sample allows its source to be pinned down, whether it is from a recently operating reactor or one which released the fission products some time previously, according to the presence or otherwise of short lived fission products. MINOR ACTINIDES The actinides are all those nuclides from actinium (89) and upwards in the Periodic Table. Apart from uranium (and possibly thorium is a thorium fuelled reactor), they are all generated from neutron captures and/or decays. They tend to be long lived and alpha-unstable and are important contributors to radionuclide toxicity is released to the environment. TRANSURANICS U & Pu classified separately All others (Th, Pa, Np, Am, Cm etc classed as Minor Actinides (MAs)) Solid waste route

Increase in Waste volume to GDF
FISSION PRODUCTS Some are stable, some short, medium and long half-lives Some are important radiologically eg I-131, Cs-137 Some are important as neutron poisons eg Xe-135, Sm-149 Some are gaseous and build-up in the fuel matrix causing swelling and may be released into the fuel rod Strong source of alpha, bets and gamma activity in irradiated fuel Strong heat source in fuel - FP decay heating is the principal safety consideration in-reactor The fission products include ones which are stable, ones with very short half-lives of seconds or less, ones with short half-lives of minutes to hours, ones with longer half-lives varying from a few years to hundreds of thousands of years. The most significant ones radiologically are those with medium half-lives such as 131I and 137Cs which have high activities, which are gaseous and therefore mobile. 131I has a half-life of 8 days and is therefore important in the short term after a release. 137Cs is more persistent, with a 30 year half-life. The mix of fission products in a contaminated sample allows its source to be pinned down, whether it is from a recently operating reactor or one which released the fission products some time previously, according to the presence or otherwise of short lived fission products. MINOR ACTINIDES The actinides are all those nuclides from actinium (89) and upwards in the Periodic Table. Apart from uranium (and possibly thorium is a thorium fuelled reactor), they are all generated from neutron captures and/or decays. They tend to be long lived and alpha-unstable and are important contributors to radionuclide toxicity is released to the environment. TRANSURANICS U & Pu classified separately All others (Th, Pa, Np, Am, Cm etc classed as Minor Actinides (MAs)) Increase in Waste volume to GDF

Strategy Requirements
FISSION PRODUCTS Some are stable, some short, medium and long half-lives Some are important radiologically eg I-131, Cs-137 Some are important as neutron poisons eg Xe-135, Sm-149 Some are gaseous and build-up in the fuel matrix causing swelling and may be released into the fuel rod Strong source of alpha, bets and gamma activity in irradiated fuel Strong heat source in fuel - FP decay heating is the principal safety consideration in-reactor The fission products include ones which are stable, ones with very short half-lives of seconds or less, ones with short half-lives of minutes to hours, ones with longer half-lives varying from a few years to hundreds of thousands of years. The most significant ones radiologically are those with medium half-lives such as 131I and 137Cs which have high activities, which are gaseous and therefore mobile. 131I has a half-life of 8 days and is therefore important in the short term after a release. 137Cs is more persistent, with a 30 year half-life. The mix of fission products in a contaminated sample allows its source to be pinned down, whether it is from a recently operating reactor or one which released the fission products some time previously, according to the presence or otherwise of short lived fission products. MINOR ACTINIDES The actinides are all those nuclides from actinium (89) and upwards in the Periodic Table. Apart from uranium (and possibly thorium is a thorium fuelled reactor), they are all generated from neutron captures and/or decays. They tend to be long lived and alpha-unstable and are important contributors to radionuclide toxicity is released to the environment. TRANSURANICS U & Pu classified separately All others (Th, Pa, Np, Am, Cm etc classed as Minor Actinides (MAs))

DAF as an alternative Technology:
Consistent fine bubble generation with no external equipment or spargers. Intense mixing with small bubbles achieving rapid flotation without mechanical agitation. High throughput in a small footprint. Fast response and easy control. Steady operation and performance irrespective of changes in feed flow. No moving parts, simple to install and maintain, excellent availability. FISSION PRODUCTS Some are stable, some short, medium and long half-lives Some are important radiologically eg I-131, Cs-137 Some are important as neutron poisons eg Xe-135, Sm-149 Some are gaseous and build-up in the fuel matrix causing swelling and may be released into the fuel rod Strong source of alpha, bets and gamma activity in irradiated fuel Strong heat source in fuel - FP decay heating is the principal safety consideration in-reactor The fission products include ones which are stable, ones with very short half-lives of seconds or less, ones with short half-lives of minutes to hours, ones with longer half-lives varying from a few years to hundreds of thousands of years. The most significant ones radiologically are those with medium half-lives such as 131I and 137Cs which have high activities, which are gaseous and therefore mobile. 131I has a half-life of 8 days and is therefore important in the short term after a release. 137Cs is more persistent, with a 30 year half-life. The mix of fission products in a contaminated sample allows its source to be pinned down, whether it is from a recently operating reactor or one which released the fission products some time previously, according to the presence or otherwise of short lived fission products. MINOR ACTINIDES The actinides are all those nuclides from actinium (89) and upwards in the Periodic Table. Apart from uranium (and possibly thorium is a thorium fuelled reactor), they are all generated from neutron captures and/or decays. They tend to be long lived and alpha-unstable and are important contributors to radionuclide toxicity is released to the environment. TRANSURANICS U & Pu classified separately All others (Th, Pa, Np, Am, Cm etc classed as Minor Actinides (MAs))

DAF How does it work? FISSION PRODUCTS MINOR ACTINIDES TRANSURANICS

Collector Adsorption to Mg(OH)2
Initial coverage Monolayer coverage Bilayer coverage Collector Adsorption to Mg(OH)2 Sodium Dodecyl Sulphate selected as a collector due to its anionic hydrophilic head group FISSION PRODUCTS Some are stable, some short, medium and long half-lives Some are important radiologically eg I-131, Cs-137 Some are important as neutron poisons eg Xe-135, Sm-149 Some are gaseous and build-up in the fuel matrix causing swelling and may be released into the fuel rod Strong source of alpha, bets and gamma activity in irradiated fuel Strong heat source in fuel - FP decay heating is the principal safety consideration in-reactor The fission products include ones which are stable, ones with very short half-lives of seconds or less, ones with short half-lives of minutes to hours, ones with longer half-lives varying from a few years to hundreds of thousands of years. The most significant ones radiologically are those with medium half-lives such as 131I and 137Cs which have high activities, which are gaseous and therefore mobile. 131I has a half-life of 8 days and is therefore important in the short term after a release. 137Cs is more persistent, with a 30 year half-life. The mix of fission products in a contaminated sample allows its source to be pinned down, whether it is from a recently operating reactor or one which released the fission products some time previously, according to the presence or otherwise of short lived fission products. MINOR ACTINIDES The actinides are all those nuclides from actinium (89) and upwards in the Periodic Table. Apart from uranium (and possibly thorium is a thorium fuelled reactor), they are all generated from neutron captures and/or decays. They tend to be long lived and alpha-unstable and are important contributors to radionuclide toxicity is released to the environment. TRANSURANICS U & Pu classified separately All others (Th, Pa, Np, Am, Cm etc classed as Minor Actinides (MAs)) Methyl isobutyl carbinol was selected as a frothing agent

DAF experimental set-up and investigated properties:

Recovery Percentage (R%) 𝑅 % = 𝑀 𝑟 𝑀 𝑇 ×100% FISSION PRODUCTS Some are stable, some short, medium and long half-lives Some are important radiologically eg I-131, Cs-137 Some are important as neutron poisons eg Xe-135, Sm-149 Some are gaseous and build-up in the fuel matrix causing swelling and may be released into the fuel rod Strong source of alpha, bets and gamma activity in irradiated fuel Strong heat source in fuel - FP decay heating is the principal safety consideration in-reactor The fission products include ones which are stable, ones with very short half-lives of seconds or less, ones with short half-lives of minutes to hours, ones with longer half-lives varying from a few years to hundreds of thousands of years. The most significant ones radiologically are those with medium half-lives such as 131I and 137Cs which have high activities, which are gaseous and therefore mobile. 131I has a half-life of 8 days and is therefore important in the short term after a release. 137Cs is more persistent, with a 30 year half-life. The mix of fission products in a contaminated sample allows its source to be pinned down, whether it is from a recently operating reactor or one which released the fission products some time previously, according to the presence or otherwise of short lived fission products. MINOR ACTINIDES The actinides are all those nuclides from actinium (89) and upwards in the Periodic Table. Apart from uranium (and possibly thorium is a thorium fuelled reactor), they are all generated from neutron captures and/or decays. They tend to be long lived and alpha-unstable and are important contributors to radionuclide toxicity is released to the environment. TRANSURANICS U & Pu classified separately All others (Th, Pa, Np, Am, Cm etc classed as Minor Actinides (MAs))

Recovery Percentage (R%) 𝑅 % = 𝑀 𝑟 𝑀 𝑇 ×100% Residual Volumetric Concentration (ξ%) 𝜉 % = (𝑀 𝑇 − 𝑀 𝑟 )/ 𝜌 𝑀𝑔 𝑂𝐻 𝑉 𝑇 − 𝑉 𝑟 ×100% FISSION PRODUCTS Some are stable, some short, medium and long half-lives Some are important radiologically eg I-131, Cs-137 Some are important as neutron poisons eg Xe-135, Sm-149 Some are gaseous and build-up in the fuel matrix causing swelling and may be released into the fuel rod Strong source of alpha, bets and gamma activity in irradiated fuel Strong heat source in fuel - FP decay heating is the principal safety consideration in-reactor The fission products include ones which are stable, ones with very short half-lives of seconds or less, ones with short half-lives of minutes to hours, ones with longer half-lives varying from a few years to hundreds of thousands of years. The most significant ones radiologically are those with medium half-lives such as 131I and 137Cs which have high activities, which are gaseous and therefore mobile. 131I has a half-life of 8 days and is therefore important in the short term after a release. 137Cs is more persistent, with a 30 year half-life. The mix of fission products in a contaminated sample allows its source to be pinned down, whether it is from a recently operating reactor or one which released the fission products some time previously, according to the presence or otherwise of short lived fission products. MINOR ACTINIDES The actinides are all those nuclides from actinium (89) and upwards in the Periodic Table. Apart from uranium (and possibly thorium is a thorium fuelled reactor), they are all generated from neutron captures and/or decays. They tend to be long lived and alpha-unstable and are important contributors to radionuclide toxicity is released to the environment. TRANSURANICS U & Pu classified separately All others (Th, Pa, Np, Am, Cm etc classed as Minor Actinides (MAs))

Recovery Percentage (R%) 𝑅 % = 𝑀 𝑟 𝑀 𝑇 ×100% Residual Volumetric Concentration (ξ%) 𝜉 % = (𝑀 𝑇 − 𝑀 𝑟 )/ 𝜌 𝑀𝑔 𝑂𝐻 𝑉 𝑇 − 𝑉 𝑟 ×100% FISSION PRODUCTS Some are stable, some short, medium and long half-lives Some are important radiologically eg I-131, Cs-137 Some are important as neutron poisons eg Xe-135, Sm-149 Some are gaseous and build-up in the fuel matrix causing swelling and may be released into the fuel rod Strong source of alpha, bets and gamma activity in irradiated fuel Strong heat source in fuel - FP decay heating is the principal safety consideration in-reactor The fission products include ones which are stable, ones with very short half-lives of seconds or less, ones with short half-lives of minutes to hours, ones with longer half-lives varying from a few years to hundreds of thousands of years. The most significant ones radiologically are those with medium half-lives such as 131I and 137Cs which have high activities, which are gaseous and therefore mobile. 131I has a half-life of 8 days and is therefore important in the short term after a release. 137Cs is more persistent, with a 30 year half-life. The mix of fission products in a contaminated sample allows its source to be pinned down, whether it is from a recently operating reactor or one which released the fission products some time previously, according to the presence or otherwise of short lived fission products. MINOR ACTINIDES The actinides are all those nuclides from actinium (89) and upwards in the Periodic Table. Apart from uranium (and possibly thorium is a thorium fuelled reactor), they are all generated from neutron captures and/or decays. They tend to be long lived and alpha-unstable and are important contributors to radionuclide toxicity is released to the environment. TRANSURANICS U & Pu classified separately All others (Th, Pa, Np, Am, Cm etc classed as Minor Actinides (MAs)) Volume Reduction Factor (Vred) 𝑉 𝑟𝑒𝑑 = 𝑉 𝑇 𝑉 𝑟

Recovery percentage: FISSION PRODUCTS MINOR ACTINIDES TRANSURANICS

General increase with increasing dose of SDS
Recovery percentage: General increase with increasing dose of SDS Plateaus at a maximum of 93% Contrary to adsorption data on the face of it FISSION PRODUCTS Some are stable, some short, medium and long half-lives Some are important radiologically eg I-131, Cs-137 Some are important as neutron poisons eg Xe-135, Sm-149 Some are gaseous and build-up in the fuel matrix causing swelling and may be released into the fuel rod Strong source of alpha, bets and gamma activity in irradiated fuel Strong heat source in fuel - FP decay heating is the principal safety consideration in-reactor The fission products include ones which are stable, ones with very short half-lives of seconds or less, ones with short half-lives of minutes to hours, ones with longer half-lives varying from a few years to hundreds of thousands of years. The most significant ones radiologically are those with medium half-lives such as 131I and 137Cs which have high activities, which are gaseous and therefore mobile. 131I has a half-life of 8 days and is therefore important in the short term after a release. 137Cs is more persistent, with a 30 year half-life. The mix of fission products in a contaminated sample allows its source to be pinned down, whether it is from a recently operating reactor or one which released the fission products some time previously, according to the presence or otherwise of short lived fission products. MINOR ACTINIDES The actinides are all those nuclides from actinium (89) and upwards in the Periodic Table. Apart from uranium (and possibly thorium is a thorium fuelled reactor), they are all generated from neutron captures and/or decays. They tend to be long lived and alpha-unstable and are important contributors to radionuclide toxicity is released to the environment. TRANSURANICS U & Pu classified separately All others (Th, Pa, Np, Am, Cm etc classed as Minor Actinides (MAs))

General increase with increasing dose of SDS
Recovery percentage: General increase with increasing dose of SDS Plateaus at a maximum of 93% Contrary to adsorption data on the face of it Optimum should be around μM but extraction increase continues FISSION PRODUCTS Some are stable, some short, medium and long half-lives Some are important radiologically eg I-131, Cs-137 Some are important as neutron poisons eg Xe-135, Sm-149 Some are gaseous and build-up in the fuel matrix causing swelling and may be released into the fuel rod Strong source of alpha, bets and gamma activity in irradiated fuel Strong heat source in fuel - FP decay heating is the principal safety consideration in-reactor The fission products include ones which are stable, ones with very short half-lives of seconds or less, ones with short half-lives of minutes to hours, ones with longer half-lives varying from a few years to hundreds of thousands of years. The most significant ones radiologically are those with medium half-lives such as 131I and 137Cs which have high activities, which are gaseous and therefore mobile. 131I has a half-life of 8 days and is therefore important in the short term after a release. 137Cs is more persistent, with a 30 year half-life. The mix of fission products in a contaminated sample allows its source to be pinned down, whether it is from a recently operating reactor or one which released the fission products some time previously, according to the presence or otherwise of short lived fission products. MINOR ACTINIDES The actinides are all those nuclides from actinium (89) and upwards in the Periodic Table. Apart from uranium (and possibly thorium is a thorium fuelled reactor), they are all generated from neutron captures and/or decays. They tend to be long lived and alpha-unstable and are important contributors to radionuclide toxicity is released to the environment. TRANSURANICS U & Pu classified separately All others (Th, Pa, Np, Am, Cm etc classed as Minor Actinides (MAs))

Recovery Factor and Residuals Concentration:

Entrainment: Bubble of air Entrained fluid FISSION PRODUCTS

Entrainment (ideal case):
Bubble of air Entrained fluid Surface modified Mg(OH)2 at the air water interface FISSION PRODUCTS Some are stable, some short, medium and long half-lives Some are important radiologically eg I-131, Cs-137 Some are important as neutron poisons eg Xe-135, Sm-149 Some are gaseous and build-up in the fuel matrix causing swelling and may be released into the fuel rod Strong source of alpha, bets and gamma activity in irradiated fuel Strong heat source in fuel - FP decay heating is the principal safety consideration in-reactor The fission products include ones which are stable, ones with very short half-lives of seconds or less, ones with short half-lives of minutes to hours, ones with longer half-lives varying from a few years to hundreds of thousands of years. The most significant ones radiologically are those with medium half-lives such as 131I and 137Cs which have high activities, which are gaseous and therefore mobile. 131I has a half-life of 8 days and is therefore important in the short term after a release. 137Cs is more persistent, with a 30 year half-life. The mix of fission products in a contaminated sample allows its source to be pinned down, whether it is from a recently operating reactor or one which released the fission products some time previously, according to the presence or otherwise of short lived fission products. MINOR ACTINIDES The actinides are all those nuclides from actinium (89) and upwards in the Periodic Table. Apart from uranium (and possibly thorium is a thorium fuelled reactor), they are all generated from neutron captures and/or decays. They tend to be long lived and alpha-unstable and are important contributors to radionuclide toxicity is released to the environment. TRANSURANICS U & Pu classified separately All others (Th, Pa, Np, Am, Cm etc classed as Minor Actinides (MAs))

Entrainment (real case):
Bubble of air Entrained fluid Surface modified Mg(OH)2 at the air water interface FISSION PRODUCTS Some are stable, some short, medium and long half-lives Some are important radiologically eg I-131, Cs-137 Some are important as neutron poisons eg Xe-135, Sm-149 Some are gaseous and build-up in the fuel matrix causing swelling and may be released into the fuel rod Strong source of alpha, bets and gamma activity in irradiated fuel Strong heat source in fuel - FP decay heating is the principal safety consideration in-reactor The fission products include ones which are stable, ones with very short half-lives of seconds or less, ones with short half-lives of minutes to hours, ones with longer half-lives varying from a few years to hundreds of thousands of years. The most significant ones radiologically are those with medium half-lives such as 131I and 137Cs which have high activities, which are gaseous and therefore mobile. 131I has a half-life of 8 days and is therefore important in the short term after a release. 137Cs is more persistent, with a 30 year half-life. The mix of fission products in a contaminated sample allows its source to be pinned down, whether it is from a recently operating reactor or one which released the fission products some time previously, according to the presence or otherwise of short lived fission products. MINOR ACTINIDES The actinides are all those nuclides from actinium (89) and upwards in the Periodic Table. Apart from uranium (and possibly thorium is a thorium fuelled reactor), they are all generated from neutron captures and/or decays. They tend to be long lived and alpha-unstable and are important contributors to radionuclide toxicity is released to the environment. TRANSURANICS U & Pu classified separately All others (Th, Pa, Np, Am, Cm etc classed as Minor Actinides (MAs)) Surface modified Mg(OH)2 in the entrained fluid (too small to float)

Slipstream displacement:
-As a bubble rises, it displaces fluid and forms a slipstream -Smaller now hydrophobic particulates get caught in this slipstream unable to interact with the water-air interface -Floatation sweet spot roughly μm FISSION PRODUCTS Some are stable, some short, medium and long half-lives Some are important radiologically eg I-131, Cs-137 Some are important as neutron poisons eg Xe-135, Sm-149 Some are gaseous and build-up in the fuel matrix causing swelling and may be released into the fuel rod Strong source of alpha, bets and gamma activity in irradiated fuel Strong heat source in fuel - FP decay heating is the principal safety consideration in-reactor The fission products include ones which are stable, ones with very short half-lives of seconds or less, ones with short half-lives of minutes to hours, ones with longer half-lives varying from a few years to hundreds of thousands of years. The most significant ones radiologically are those with medium half-lives such as 131I and 137Cs which have high activities, which are gaseous and therefore mobile. 131I has a half-life of 8 days and is therefore important in the short term after a release. 137Cs is more persistent, with a 30 year half-life. The mix of fission products in a contaminated sample allows its source to be pinned down, whether it is from a recently operating reactor or one which released the fission products some time previously, according to the presence or otherwise of short lived fission products. MINOR ACTINIDES The actinides are all those nuclides from actinium (89) and upwards in the Periodic Table. Apart from uranium (and possibly thorium is a thorium fuelled reactor), they are all generated from neutron captures and/or decays. They tend to be long lived and alpha-unstable and are important contributors to radionuclide toxicity is released to the environment. TRANSURANICS U & Pu classified separately All others (Th, Pa, Np, Am, Cm etc classed as Minor Actinides (MAs))

Conclusions: Given the surface charge properties of the suspended Mg(OH)2 in Sellafield’s First- Generation Magnox Storage pond, an anionic surfactant such as sodium dodecyl sulphate can be used for rapid extraction. The technology is successful in extracting Mg(OH)2 via hydrophobic interaction with SDS Addresses UK nuclear specific issues (low foot print, no moving parts etc.) Monolayer development concentration found in this paper to be in the range of μM. Optimisation of frother agent with determined optimum collector concentration for reduction in entrainment carry over work still required FISSION PRODUCTS Some are stable, some short, medium and long half-lives Some are important radiologically eg I-131, Cs-137 Some are important as neutron poisons eg Xe-135, Sm-149 Some are gaseous and build-up in the fuel matrix causing swelling and may be released into the fuel rod Strong source of alpha, bets and gamma activity in irradiated fuel Strong heat source in fuel - FP decay heating is the principal safety consideration in-reactor The fission products include ones which are stable, ones with very short half-lives of seconds or less, ones with short half-lives of minutes to hours, ones with longer half-lives varying from a few years to hundreds of thousands of years. The most significant ones radiologically are those with medium half-lives such as 131I and 137Cs which have high activities, which are gaseous and therefore mobile. 131I has a half-life of 8 days and is therefore important in the short term after a release. 137Cs is more persistent, with a 30 year half-life. The mix of fission products in a contaminated sample allows its source to be pinned down, whether it is from a recently operating reactor or one which released the fission products some time previously, according to the presence or otherwise of short lived fission products. MINOR ACTINIDES The actinides are all those nuclides from actinium (89) and upwards in the Periodic Table. Apart from uranium (and possibly thorium is a thorium fuelled reactor), they are all generated from neutron captures and/or decays. They tend to be long lived and alpha-unstable and are important contributors to radionuclide toxicity is released to the environment. TRANSURANICS U & Pu classified separately All others (Th, Pa, Np, Am, Cm etc classed as Minor Actinides (MAs))

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Decommissioning of Spent Nuclear Fuel Ponds University of Leeds Student Sustainability Research Conference 2019, Leeds, UK. Alexander P. G. Lockwood,

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Decommissioning of Spent Nuclear Fuel Ponds University of Leeds Student Sustainability Research Conference 2019, Leeds, UK. Alexander P. G. Lockwood,

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Presentation on theme: "Decommissioning of Spent Nuclear Fuel Ponds University of Leeds Student Sustainability Research Conference 2019, Leeds, UK. Alexander P. G. Lockwood,"— Presentation transcript:

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