To achieve the resource utilization of solid waste phosphogypsum(PG)and tackle the problem of utilizing potassium feldspar(PF),a coupled synergistic process between PG and PF is proposed in this paper.The study invest...To achieve the resource utilization of solid waste phosphogypsum(PG)and tackle the problem of utilizing potassium feldspar(PF),a coupled synergistic process between PG and PF is proposed in this paper.The study investigates the features of P and F in PG,and explores the decomposition of PF using hydrofluoric acid(HF)in the sulfuric acid system for K leaching and leaching of P and F in PG.The impact factors such as sulfuric acid concentration,reaction temperature,reaction time,material ratio(PG/PF),liquid–solid ratio,PF particle size,and PF calcination temperature on the leaching of P and K is systematically investigated in this paper.The results show that under optimal conditions,the leaching rate of K and P reach more than 93%and 96%,respectively.Kinetics study using shrinking core model(SCM)indicates two significant stages with internal diffusion predominantly controlling the leaching of K.The apparent activation energies of these two stages are 11.92 kJ·mol^(-1)and 11.55 kJ·mol^(-1),respectively.展开更多
Electrocatalysis offers efficient and targeted conversion of monomers derived from waste polyester plastics to chemical products under ambient temperature and pressure conditions.This review provides analysis of resea...Electrocatalysis offers efficient and targeted conversion of monomers derived from waste polyester plastics to chemical products under ambient temperature and pressure conditions.This review provides analysis of research on electrochemical upgrading of monomers derived from waste polyester plastics published from2021 to present.Factors for assessing upgrading of waste polyester plastics include alkaline hydrolysis pretreatment,indices of electrochemical reaction process(activity,stability,and techno-economic a nalysis),separation,and product recovery.Types of depolymerization monomers and their value-added products are summarized along with electrocatalytic mechanisms and reaction pathways.Notably,cathode coupled reactions offer significant value for anodic waste plastic oxidation during electrolysis processes.Development of bifunctional electrocatalysts can reduce the cost of coupled systems and complexity of the electrolyzer.Upgrading and recycling of waste plastic monomers using electrocatalytic technology should undergo downstream processing to form high-value products containing C-N and C-S derived functional groups obtained from depolymerized monomers,Electrochemical conversion and upgrading of monomers derived from waste polyester plastics can contribute to industrialization and global economies and help to realize environmental sustainability.展开更多
The management of nitrogenous waste emissions presents significant environmental and health challenges.Efficient and sustainable upcycling strategies are needed to convert waste nitrogen compounds into valuable resour...The management of nitrogenous waste emissions presents significant environmental and health challenges.Efficient and sustainable upcycling strategies are needed to convert waste nitrogen compounds into valuable resources.Electrocatalysis has emerged as a promising solution for waste management,but several challenges remain,including the identification of suitable electrocatalysts and understanding the complex reaction mechanisms.In this review,we focus on the progress in electrocatalytic oxidized nitrogen waste upgrading and utilization,highlighting the application of advanced in situ/operando characterization techniques,including X-ray spectroscopy,scanning electrochemical microscopy and others.These techniques provide valuable insights into the structural and chemical properties of electrocatalysts as well as intermediates during electrochemical reactions,enabling a better understanding of reaction mechanisms and optimization of reaction conditions.The review explores the mechanisms of electrocatalytic upcycling of nitrogenous waste,including nitrate/nitrite reduction,nitric oxide reduction,and carbon dioxide and nitrate co-reduction reactions.Additionally,future research directions and development trends are discussed,offering a relevant guide for the development of sustainable electrocatalytic technologies for waste management and resource recovery.展开更多
This work is devoted to numerical analysis of thermo-hydromechanical problem and cracking process in saturated porous media in the context of deep geological disposal of radioactive waste.The fundamental background of...This work is devoted to numerical analysis of thermo-hydromechanical problem and cracking process in saturated porous media in the context of deep geological disposal of radioactive waste.The fundamental background of thermo-poro-elastoplasticity theory is first summarized.The emphasis is put on the effect of pore fluid pressure on plastic deformation.A micromechanics-based elastoplastic model is then presented for a class of clayey rocks considered as host rock.Based on linear and nonlinear homogenization techniques,the proposed model is able to systematically account for the influences of porosity and mineral composition on macroscopic elastic properties and plastic yield strength.The initial anisotropy and time-dependent deformation are also taken into account.The induced cracking process is described by using a non-local damage model.A specific hybrid formulation is proposed,able to conveniently capture tensile,shear and mixed cracks.In particular,the influences of pore pressure and confining stress on the shear cracking mechanism are taken into account.The proposed model is applied to investigating thermo-hydromechanical responses and induced damage evolution in laboratory tests at the sample scale.In the last part,an in situ heating experiment is analyzed by using the proposed model.Numerical results are compared with experimental data and field measurements in terms of temperature variation,pore fluid pressure change and induced damaged zone.展开更多
A fully coupled thermo-hydro-mechano-chemical（THMC） formulation is described in this paper.Special attention is paid to phenomena likely to be encountered in clay barriers used as engineered barriers in the disposal...A fully coupled thermo-hydro-mechano-chemical（THMC） formulation is described in this paper.Special attention is paid to phenomena likely to be encountered in clay barriers used as engineered barriers in the disposal of nuclear radioactive waste.The types of processes considered in the chemical formulation include hydrolysis,complex formation,oxidation/reduction reactions,acid/base reactions,precipitation/dissolution of minerals and cation exchange.Both kinetics-and equilibrium-controlled reactions are incorporated.The formulation is implemented in a numerical code.An application is presented concerning the performance of a large-scale in-situ heating test simulating high-level radioactive waste repository conditions.展开更多
An important challenge in ensuring the long-term effectiveness of geological nuclear waste disposal is predicting the transportation of decay heat and gases released from nuclear waste canisters.In this study,thermo-h...An important challenge in ensuring the long-term effectiveness of geological nuclear waste disposal is predicting the transportation of decay heat and gases released from nuclear waste canisters.In this study,thermo-hydromechanical(THM)coupled simulations were conducted using the TOUGH + FLAC3D simulator to predict the THM behaviors of a generic nuclear waste repository over 100,000 years following closure.The designed engineered barrier system(EBS)consists of the waste canister,backfill,and concrete liner.The objective of this study is to evaluate the long-term performance of the repository in the presence of continued hydrogen(H_(2))and heat release around the canister.The simulation results show that thermal pressurization and gas accumulation significantly raise the pore pressure within the EBS and surrounding host rock,while the peak pore pressure is not likely to exceed the lithostatic stress so that there is no risk of widespread hydro-fracturing in the host rock.However,tension failure and fracturing can occur at the tunnel scale because of internal gas buildup.Meanwhile,the generated H_(2) continuously migrates outward and tends to accumulate in the concrete liner and excavation disturbed zone surrounding the tunnel because of lower capillary pressure.Nevertheless,the fluids that may contain radionuclides will not leach into the confining units over a 100,000-year time frame.Our analysis indicates that for the assumed disposal system in Opalinus Clay,the generated heat and gas can gradually be transported through the host rock without significantly disturbing the isolation characteristics of the repository.展开更多
在当前数字化时代,互联网数据中心(internet data center,IDC)(以下简称“数据中心”)作为大型的电力消耗者已经成为电力网络中的重要组成部分。首先采用数据中心余热回收技术建立了数据中心等值热参数模型,并将其融入到微能源网中以实...在当前数字化时代,互联网数据中心(internet data center,IDC)(以下简称“数据中心”)作为大型的电力消耗者已经成为电力网络中的重要组成部分。首先采用数据中心余热回收技术建立了数据中心等值热参数模型,并将其融入到微能源网中以实现冷热电多能互补。其次对数据中心运行过程中所需制冷量与余热之间的复杂关系进行了深入分析,采用溴化锂吸收式制冷机和电制冷机来满足数据中心的冷负荷需求。为了更有效地应对批处理负荷在时间维度上的变化特性,制定了高度灵活的数据负荷分配策略,并建立了双层规划模型。使用场景削减的典型日选择方法以应对源荷不确定性,并引入基于Tent映射的灰狼优化算法(Tent mapping grey wolf optimization algorithm,TMGWO)和CPLEX进行联合求解。最后,通过对某含数据中心的微能源网系统进行仿真分析,数值计算结果表明所提出的方法能够有效提高系统的经济性和环保性。展开更多
基金jointly supported by the National Key Research and Development Program of China (2019YFC1905800)the National Key Research & Development Program of China (2018YFC1903500)+4 种基金the commercial project by Beijing Zhong Dian Hua Yuan Environment Protection Technology Co., Ltd. (E01211200005)the Regional key projects of the science and technology service network program (STS program) of the Chinese Academy of Sciences (KFJ-STS-QYZD-153)the Ningbo Science and Technology Innovation Key Projects (2020Z099, 2022Z028)the Ningbo Municipal Commonweal Key Program (2019C10033)the support of Mineral Resources Analytical and Testing Center, Institute of Process Engineering, Chinese Academy of Science
文摘To achieve the resource utilization of solid waste phosphogypsum(PG)and tackle the problem of utilizing potassium feldspar(PF),a coupled synergistic process between PG and PF is proposed in this paper.The study investigates the features of P and F in PG,and explores the decomposition of PF using hydrofluoric acid(HF)in the sulfuric acid system for K leaching and leaching of P and F in PG.The impact factors such as sulfuric acid concentration,reaction temperature,reaction time,material ratio(PG/PF),liquid–solid ratio,PF particle size,and PF calcination temperature on the leaching of P and K is systematically investigated in this paper.The results show that under optimal conditions,the leaching rate of K and P reach more than 93%and 96%,respectively.Kinetics study using shrinking core model(SCM)indicates two significant stages with internal diffusion predominantly controlling the leaching of K.The apparent activation energies of these two stages are 11.92 kJ·mol^(-1)and 11.55 kJ·mol^(-1),respectively.
基金financially supported by the National Natural Science Foundation of China(Nos.22178181)the Natural Science Fund of Tianjin(No.21JCZDJC00180)the Fundamental Research Funds for the Central Universities(Nankai University(No.63243129)).
文摘Electrocatalysis offers efficient and targeted conversion of monomers derived from waste polyester plastics to chemical products under ambient temperature and pressure conditions.This review provides analysis of research on electrochemical upgrading of monomers derived from waste polyester plastics published from2021 to present.Factors for assessing upgrading of waste polyester plastics include alkaline hydrolysis pretreatment,indices of electrochemical reaction process(activity,stability,and techno-economic a nalysis),separation,and product recovery.Types of depolymerization monomers and their value-added products are summarized along with electrocatalytic mechanisms and reaction pathways.Notably,cathode coupled reactions offer significant value for anodic waste plastic oxidation during electrolysis processes.Development of bifunctional electrocatalysts can reduce the cost of coupled systems and complexity of the electrolyzer.Upgrading and recycling of waste plastic monomers using electrocatalytic technology should undergo downstream processing to form high-value products containing C-N and C-S derived functional groups obtained from depolymerized monomers,Electrochemical conversion and upgrading of monomers derived from waste polyester plastics can contribute to industrialization and global economies and help to realize environmental sustainability.
基金supported by the National Key Research and Development Project(No.2022YFA1505300)National Nature Science Foundation of China(Nos.52202372 and 22304021)Sichuan Science and Technology Program(Nos.2023NSFSC0089 and 2023NSFSC0436).
文摘The management of nitrogenous waste emissions presents significant environmental and health challenges.Efficient and sustainable upcycling strategies are needed to convert waste nitrogen compounds into valuable resources.Electrocatalysis has emerged as a promising solution for waste management,but several challenges remain,including the identification of suitable electrocatalysts and understanding the complex reaction mechanisms.In this review,we focus on the progress in electrocatalytic oxidized nitrogen waste upgrading and utilization,highlighting the application of advanced in situ/operando characterization techniques,including X-ray spectroscopy,scanning electrochemical microscopy and others.These techniques provide valuable insights into the structural and chemical properties of electrocatalysts as well as intermediates during electrochemical reactions,enabling a better understanding of reaction mechanisms and optimization of reaction conditions.The review explores the mechanisms of electrocatalytic upcycling of nitrogenous waste,including nitrate/nitrite reduction,nitric oxide reduction,and carbon dioxide and nitrate co-reduction reactions.Additionally,future research directions and development trends are discussed,offering a relevant guide for the development of sustainable electrocatalytic technologies for waste management and resource recovery.
基金supported by the French National Agency for radioactive waste management(ANDRA).
文摘This work is devoted to numerical analysis of thermo-hydromechanical problem and cracking process in saturated porous media in the context of deep geological disposal of radioactive waste.The fundamental background of thermo-poro-elastoplasticity theory is first summarized.The emphasis is put on the effect of pore fluid pressure on plastic deformation.A micromechanics-based elastoplastic model is then presented for a class of clayey rocks considered as host rock.Based on linear and nonlinear homogenization techniques,the proposed model is able to systematically account for the influences of porosity and mineral composition on macroscopic elastic properties and plastic yield strength.The initial anisotropy and time-dependent deformation are also taken into account.The induced cracking process is described by using a non-local damage model.A specific hybrid formulation is proposed,able to conveniently capture tensile,shear and mixed cracks.In particular,the influences of pore pressure and confining stress on the shear cracking mechanism are taken into account.The proposed model is applied to investigating thermo-hydromechanical responses and induced damage evolution in laboratory tests at the sample scale.In the last part,an in situ heating experiment is analyzed by using the proposed model.Numerical results are compared with experimental data and field measurements in terms of temperature variation,pore fluid pressure change and induced damaged zone.
基金supported by ENRESA and the European Commissionsupport given by CNPq(Conselho Nacional de Desenvolvimento Cientíco e Tecnológico)and the assistance of the Ministerio de Ciencia y Tecnología of Spain through research grant(BIA2008-06537)
文摘A fully coupled thermo-hydro-mechano-chemical（THMC） formulation is described in this paper.Special attention is paid to phenomena likely to be encountered in clay barriers used as engineered barriers in the disposal of nuclear radioactive waste.The types of processes considered in the chemical formulation include hydrolysis,complex formation,oxidation/reduction reactions,acid/base reactions,precipitation/dissolution of minerals and cation exchange.Both kinetics-and equilibrium-controlled reactions are incorporated.The formulation is implemented in a numerical code.An application is presented concerning the performance of a large-scale in-situ heating test simulating high-level radioactive waste repository conditions.
基金Funding was provided by the U.S.Department of Energy,Office of Nuclear Energy,Spent Fuel and Waste Disposition,under Contract Number DE-AC02-05CH11231 with Lawrence Berkeley National Laboratory(LBNL).
文摘An important challenge in ensuring the long-term effectiveness of geological nuclear waste disposal is predicting the transportation of decay heat and gases released from nuclear waste canisters.In this study,thermo-hydromechanical(THM)coupled simulations were conducted using the TOUGH + FLAC3D simulator to predict the THM behaviors of a generic nuclear waste repository over 100,000 years following closure.The designed engineered barrier system(EBS)consists of the waste canister,backfill,and concrete liner.The objective of this study is to evaluate the long-term performance of the repository in the presence of continued hydrogen(H_(2))and heat release around the canister.The simulation results show that thermal pressurization and gas accumulation significantly raise the pore pressure within the EBS and surrounding host rock,while the peak pore pressure is not likely to exceed the lithostatic stress so that there is no risk of widespread hydro-fracturing in the host rock.However,tension failure and fracturing can occur at the tunnel scale because of internal gas buildup.Meanwhile,the generated H_(2) continuously migrates outward and tends to accumulate in the concrete liner and excavation disturbed zone surrounding the tunnel because of lower capillary pressure.Nevertheless,the fluids that may contain radionuclides will not leach into the confining units over a 100,000-year time frame.Our analysis indicates that for the assumed disposal system in Opalinus Clay,the generated heat and gas can gradually be transported through the host rock without significantly disturbing the isolation characteristics of the repository.
文摘在当前数字化时代,互联网数据中心(internet data center,IDC)(以下简称“数据中心”)作为大型的电力消耗者已经成为电力网络中的重要组成部分。首先采用数据中心余热回收技术建立了数据中心等值热参数模型,并将其融入到微能源网中以实现冷热电多能互补。其次对数据中心运行过程中所需制冷量与余热之间的复杂关系进行了深入分析,采用溴化锂吸收式制冷机和电制冷机来满足数据中心的冷负荷需求。为了更有效地应对批处理负荷在时间维度上的变化特性,制定了高度灵活的数据负荷分配策略,并建立了双层规划模型。使用场景削减的典型日选择方法以应对源荷不确定性,并引入基于Tent映射的灰狼优化算法(Tent mapping grey wolf optimization algorithm,TMGWO)和CPLEX进行联合求解。最后,通过对某含数据中心的微能源网系统进行仿真分析,数值计算结果表明所提出的方法能够有效提高系统的经济性和环保性。
