Amines are well-known for their reversible reactions with CO_(2),which make them ideal for CO_(2) capture from several gas streams,including flue gas.In this respect,selective CO_(2) absorption by aqueous alkanolamine...Amines are well-known for their reversible reactions with CO_(2),which make them ideal for CO_(2) capture from several gas streams,including flue gas.In this respect,selective CO_(2) absorption by aqueous alkanolamines is the most mature technology but the process is energy intensive and has also corrosion problems.Both disadvantages can be diminished to a certain extent by chemical adsorption of CO_(2) selectively.The most important element of the chemical adsorption of CO_(2) involves the design and development of a suitable adsorbent which consist of a porous support onto which an amine is attached or immobilized.Such an adsorbent is often called as solid amine sorbent.This review covers solid amine-based studies which are developed and published in recent years.First,the review examines several different types of porous support materials,namely,three mesoporous silica(MCM-41,SBA-15 and KIT-6)and two polymeric supports(PMMA and PS)for CO_(2) adsorption.Emphasis is given to the synthesis,modifications and characterizations-such as BET and PXRD data-of them.Amination of these supports to obtain a solid amine sorbent through impregnation or grafting is reviewed comparatively.Focus is given to the adsorption mechanisms,material characteristics,and synthesis methods which are discussed in detail.Significant amount of original data are also presented which makes this review unique.Finally,relevant CO_(2) adsorption(or equilibrium)capacity data,and cyclic adsorption/desorption performance and stability of important classes of solid amine sorbents are critically reviewed.These include severa PEI or TEPA impregnated adsorbents and APTES-grafted systems.展开更多
Temperature-swing adsorption(TSA)is an effective technique for CO_(2) capture,but the temperature swing procedure is energy-intensive.Herein,we report a low-energy-consumption system by combining passive radiative coo...Temperature-swing adsorption(TSA)is an effective technique for CO_(2) capture,but the temperature swing procedure is energy-intensive.Herein,we report a low-energy-consumption system by combining passive radiative cooling and solar heating for the uptake of CO_(2) on commercial activated carbons(CACs).During adsorption,the adsorbents are coated with a layer of hierarchically porous poly(vinylidene fluoride-co-hexafluoropropene)[P(VdF-HFP)HP],which cools the adsorbents to a low temperature under sunlight through radiative cooling.For desorption,CACs with broad absorption of the solar spectrum are exposed to light irradiation for heating.The heating and cooling processes are completely driven by solar energy.Adsorption tests under mimicked sunlight using the CACs show that the performance of this system is comparable to that of the traditional ones.Furthermore,under real sunlight irradiation,the adsorption capacity of the CACs can be well maintained after multiple cycles.The present work may inspire the development of new temperature swing procedures with little energy consumption.展开更多
In this paper,a control scheme based on current optimization is proposed for dual three-phase permanent-magnet synchronous motor(DTP-PMSM)drive to reduce the low-frequency temperature swing.The reduction of temperatur...In this paper,a control scheme based on current optimization is proposed for dual three-phase permanent-magnet synchronous motor(DTP-PMSM)drive to reduce the low-frequency temperature swing.The reduction of temperature swing can be equivalent to reducing maximum instantaneous phase copper loss in this paper.First,a two-level optimization aiming at minimizing maximum instantaneous phase copper loss at each electrical angle is proposed.Then,the optimization is transformed to a singlelevel optimization by introducing the auxiliary variable for easy solving.Considering that singleobjective optimization trades a great total copper loss for a small reduction of maximum phase copper loss,the optimization considering both instantaneous total copper loss and maximum phase copper loss is proposed,which has the same performance of temperature swing reduction but with lower total loss.In this way,the proposed control scheme can reduce maximum junction temperature by 11%.Both simulation and experimental results are presented to prove the effectiveness and superiority of the proposed control scheme for low-frequency temperature swing reduction.展开更多
Direct air capture(DAC)is one of the most potential technologies to mitigate CO_(2) emission.Adsorption technol-ogy is recognized as a promising CO_(2) capture method in view of its desirable characteristics including...Direct air capture(DAC)is one of the most potential technologies to mitigate CO_(2) emission.Adsorption technol-ogy is recognized as a promising CO_(2) capture method in view of its desirable characteristics including reusability of adsorbents and low capital investment.To further improve thermal performance,evaporation/condensation heat of vapor compression refrigeration(VCR)cycle in air condition system of buildings is adopted for adsorp-tion/desorption process of DAC.Thermal performance of a 4-step temperature swing adsorption process(TSA)is analyzed at various adsorption/desorption temperatures by using different adsorbents.Analysis on Coefficient of Performance(COP)of VCR cycle is also conducted in search for a balance between adsorbent and refrigerant.Taking both real working capacity and COP into consideration,Mg-MOF-74&R134a is the best choice for more amounts of CO_(2).Real working capacity of Mg-MOF-74 is up to 0.38 mol•kg−1 at 70°C,which is twice as much as that of zeolite 13X.While zeolite 13X&R134a shows the best performance of two cycles in view of exergy efficiency and COP,which could reach 81.9%and 7.21,respectively,at 35°C.These matches will provide some guidelines for the practical application of the combination of DAC with heating,ventilation and air conditioning(HVAC).展开更多
Using a 1-MWe slipstream pilot plant,solid-sorbent-based post-combustion CO_(2) capture was tested at a coal-fired power plant.Results from pilot testing were used to develop a preliminary full-scale commercial design...Using a 1-MWe slipstream pilot plant,solid-sorbent-based post-combustion CO_(2) capture was tested at a coal-fired power plant.Results from pilot testing were used to develop a preliminary full-scale commercial design.The sorbent selected for pilot-scale evaluation during this project consisted of an ion-exchange resin that incorporated amines covalently bonded to the substrate.A unique temperature-swing-absorption(TSA)process was developed that incorporated a three-stage fluidized-bed adsorber integrated with a single-stage fluidized-bed regenerator.Overall,following start-up and commissioning challenges that are often associated with first-of-a-kind pilots,the pilot plant operated as designed and expected,with a few key exceptions.The two primary exceptions were associated with:(i)handling characteristics of the sorbent,which were sufficiently different at operating temperature than at ambient temperature when design specifications were established with lab-scale testing;and(ii)CO_(2) adsorption in the transport line between the regenerator and adsorber that preloaded the sorbent with CO_(2) prior to entering the adsorber.Results from the pilot programme demonstrate that solid-sorbent-based post-combustion capture can be utilized to achieve 90%CO_(2) capture from coal-fired power plants.展开更多
Escalating threat of global warming and the steady growth in world population require the development of transformative greenhouse gas control technologies and food production systems of high energy efficiency,small e...Escalating threat of global warming and the steady growth in world population require the development of transformative greenhouse gas control technologies and food production systems of high energy efficiency,small environmental footprint and low cost.To control the global temperature rise below 2℃ by 2050,global greenhouse gas emissions need to be cut by more than 80%.At the same time,our land needs to be utilized more efficiently and productively in order to produce enough food to feed projected 9 billion people with less available land area for food production in 2050.We propose to develop a modern urban vertical farming system,i.e.greenhouses equipped with a Carbon Enrichment for Plant Stimulation(CEPS)system,to enhance land use efficiency and thus increase food productivity and,at the same time,to sequestrate CO_(2) from ambient air.The deployment of such a CEPS system will have a potential to remove more than 500 million tonnes CO_(2) from air annually,and increase the current food productivity by more than 15 times than the open field operation.The deployment of the CEPS technology will also promote locally produced food,benefiting urban economical development and job creation.展开更多
Post-combustion CO_(2)capture followed by sequestration is one of the only feasible means to significantly reduce CO_(2)emissions from existing fossil-fuel-fired power plants.This paper is Part 1 of a two-part paper h...Post-combustion CO_(2)capture followed by sequestration is one of the only feasible means to significantly reduce CO_(2)emissions from existing fossil-fuel-fired power plants.This paper is Part 1 of a two-part paper highlighting key results from a project sponsored by the US Department of Energy and supported by industrial groups with the objective of demonstrating the viability of solid sorbents for CO_(2)capture.The overall objective of the effort was to validate solid sorbent-based post-combustion CO_(2)capture through slipstream pilot testing at a coal-fired power plant using a temperature-swing adsorption process.In Part 1 of this work,the results from laboratory characterization of the sorbent selected for the pilot-scale demonstration are presented.A great deal of research related to sorbent development and evaluation has occurred to date but,for the most part,these promising materials have yet to be paired with a feasible process and demonstrated at the pilot scale.The sorbent selected for pilot-scale evaluation under this project consisted of an ion-exchange resin that incorporated amines that were covalently bonded to the substrate.During the sorbent characterization portion of this work,the sorbent was characterized by a range of methods intended to provide information to support the design and operation of the pilot-scale CO_(2)-capture process,including equilibrium adsorption isotherms,adsorption and regeneration kinetics,impact of moisture and oxygen on CO_(2)working capacity,sorbent thermal properties,sorbent strength and attrition,and optimum particle-size distribution.This paper reports results from sorbent characterization testing and how these characteristics influenced the type and size of the CO_(2)-capture process equipment.In Part 2 of this work,results from tests of 1-MWe pilot-scale process equipment loaded with the sorbent described in Part 1 will be presented and analysed.展开更多
基金This work has been supported by Turkish Scientific and Technological Research Council(Project Number:111A016).Authors gratefully acknowledge the financial support.
文摘Amines are well-known for their reversible reactions with CO_(2),which make them ideal for CO_(2) capture from several gas streams,including flue gas.In this respect,selective CO_(2) absorption by aqueous alkanolamines is the most mature technology but the process is energy intensive and has also corrosion problems.Both disadvantages can be diminished to a certain extent by chemical adsorption of CO_(2) selectively.The most important element of the chemical adsorption of CO_(2) involves the design and development of a suitable adsorbent which consist of a porous support onto which an amine is attached or immobilized.Such an adsorbent is often called as solid amine sorbent.This review covers solid amine-based studies which are developed and published in recent years.First,the review examines several different types of porous support materials,namely,three mesoporous silica(MCM-41,SBA-15 and KIT-6)and two polymeric supports(PMMA and PS)for CO_(2) adsorption.Emphasis is given to the synthesis,modifications and characterizations-such as BET and PXRD data-of them.Amination of these supports to obtain a solid amine sorbent through impregnation or grafting is reviewed comparatively.Focus is given to the adsorption mechanisms,material characteristics,and synthesis methods which are discussed in detail.Significant amount of original data are also presented which makes this review unique.Finally,relevant CO_(2) adsorption(or equilibrium)capacity data,and cyclic adsorption/desorption performance and stability of important classes of solid amine sorbents are critically reviewed.These include severa PEI or TEPA impregnated adsorbents and APTES-grafted systems.
基金supported by the National Science Fund for Distinguished Young Scholars(22125804)the National Natural Science Foundation of China(21808110,22078155,and 21878149).
文摘Temperature-swing adsorption(TSA)is an effective technique for CO_(2) capture,but the temperature swing procedure is energy-intensive.Herein,we report a low-energy-consumption system by combining passive radiative cooling and solar heating for the uptake of CO_(2) on commercial activated carbons(CACs).During adsorption,the adsorbents are coated with a layer of hierarchically porous poly(vinylidene fluoride-co-hexafluoropropene)[P(VdF-HFP)HP],which cools the adsorbents to a low temperature under sunlight through radiative cooling.For desorption,CACs with broad absorption of the solar spectrum are exposed to light irradiation for heating.The heating and cooling processes are completely driven by solar energy.Adsorption tests under mimicked sunlight using the CACs show that the performance of this system is comparable to that of the traditional ones.Furthermore,under real sunlight irradiation,the adsorption capacity of the CACs can be well maintained after multiple cycles.The present work may inspire the development of new temperature swing procedures with little energy consumption.
基金supported by the National Natural Science Foundation of China(No.62271109)。
文摘In this paper,a control scheme based on current optimization is proposed for dual three-phase permanent-magnet synchronous motor(DTP-PMSM)drive to reduce the low-frequency temperature swing.The reduction of temperature swing can be equivalent to reducing maximum instantaneous phase copper loss in this paper.First,a two-level optimization aiming at minimizing maximum instantaneous phase copper loss at each electrical angle is proposed.Then,the optimization is transformed to a singlelevel optimization by introducing the auxiliary variable for easy solving.Considering that singleobjective optimization trades a great total copper loss for a small reduction of maximum phase copper loss,the optimization considering both instantaneous total copper loss and maximum phase copper loss is proposed,which has the same performance of temperature swing reduction but with lower total loss.In this way,the proposed control scheme can reduce maximum junction temperature by 11%.Both simulation and experimental results are presented to prove the effectiveness and superiority of the proposed control scheme for low-frequency temperature swing reduction.
基金This research was supported by National Natural Science Foundation of China under contract number(51976178).
文摘Direct air capture(DAC)is one of the most potential technologies to mitigate CO_(2) emission.Adsorption technol-ogy is recognized as a promising CO_(2) capture method in view of its desirable characteristics including reusability of adsorbents and low capital investment.To further improve thermal performance,evaporation/condensation heat of vapor compression refrigeration(VCR)cycle in air condition system of buildings is adopted for adsorp-tion/desorption process of DAC.Thermal performance of a 4-step temperature swing adsorption process(TSA)is analyzed at various adsorption/desorption temperatures by using different adsorbents.Analysis on Coefficient of Performance(COP)of VCR cycle is also conducted in search for a balance between adsorbent and refrigerant.Taking both real working capacity and COP into consideration,Mg-MOF-74&R134a is the best choice for more amounts of CO_(2).Real working capacity of Mg-MOF-74 is up to 0.38 mol•kg−1 at 70°C,which is twice as much as that of zeolite 13X.While zeolite 13X&R134a shows the best performance of two cycles in view of exergy efficiency and COP,which could reach 81.9%and 7.21,respectively,at 35°C.These matches will provide some guidelines for the practical application of the combination of DAC with heating,ventilation and air conditioning(HVAC).
基金supported by the US Department of Energy,National Energy Technology Laboratory(DE-FE0004343)with additional support from ADA-ES,Inc.,EPRI and Southern Company.
文摘Using a 1-MWe slipstream pilot plant,solid-sorbent-based post-combustion CO_(2) capture was tested at a coal-fired power plant.Results from pilot testing were used to develop a preliminary full-scale commercial design.The sorbent selected for pilot-scale evaluation during this project consisted of an ion-exchange resin that incorporated amines covalently bonded to the substrate.A unique temperature-swing-absorption(TSA)process was developed that incorporated a three-stage fluidized-bed adsorber integrated with a single-stage fluidized-bed regenerator.Overall,following start-up and commissioning challenges that are often associated with first-of-a-kind pilots,the pilot plant operated as designed and expected,with a few key exceptions.The two primary exceptions were associated with:(i)handling characteristics of the sorbent,which were sufficiently different at operating temperature than at ambient temperature when design specifications were established with lab-scale testing;and(ii)CO_(2) adsorption in the transport line between the regenerator and adsorber that preloaded the sorbent with CO_(2) prior to entering the adsorber.Results from the pilot programme demonstrate that solid-sorbent-based post-combustion capture can be utilized to achieve 90%CO_(2) capture from coal-fired power plants.
基金Supports from Fuzhou University through a MinJiang Scholar program and Natural Science and Engineering Research Council(NSERC)of Canada through a discovery program are gratefully acknowledged.
文摘Escalating threat of global warming and the steady growth in world population require the development of transformative greenhouse gas control technologies and food production systems of high energy efficiency,small environmental footprint and low cost.To control the global temperature rise below 2℃ by 2050,global greenhouse gas emissions need to be cut by more than 80%.At the same time,our land needs to be utilized more efficiently and productively in order to produce enough food to feed projected 9 billion people with less available land area for food production in 2050.We propose to develop a modern urban vertical farming system,i.e.greenhouses equipped with a Carbon Enrichment for Plant Stimulation(CEPS)system,to enhance land use efficiency and thus increase food productivity and,at the same time,to sequestrate CO_(2) from ambient air.The deployment of such a CEPS system will have a potential to remove more than 500 million tonnes CO_(2) from air annually,and increase the current food productivity by more than 15 times than the open field operation.The deployment of the CEPS technology will also promote locally produced food,benefiting urban economical development and job creation.
基金supported by the US Department of Energy,National Energy Technology Laboratory(DE-FE0004343).
文摘Post-combustion CO_(2)capture followed by sequestration is one of the only feasible means to significantly reduce CO_(2)emissions from existing fossil-fuel-fired power plants.This paper is Part 1 of a two-part paper highlighting key results from a project sponsored by the US Department of Energy and supported by industrial groups with the objective of demonstrating the viability of solid sorbents for CO_(2)capture.The overall objective of the effort was to validate solid sorbent-based post-combustion CO_(2)capture through slipstream pilot testing at a coal-fired power plant using a temperature-swing adsorption process.In Part 1 of this work,the results from laboratory characterization of the sorbent selected for the pilot-scale demonstration are presented.A great deal of research related to sorbent development and evaluation has occurred to date but,for the most part,these promising materials have yet to be paired with a feasible process and demonstrated at the pilot scale.The sorbent selected for pilot-scale evaluation under this project consisted of an ion-exchange resin that incorporated amines that were covalently bonded to the substrate.During the sorbent characterization portion of this work,the sorbent was characterized by a range of methods intended to provide information to support the design and operation of the pilot-scale CO_(2)-capture process,including equilibrium adsorption isotherms,adsorption and regeneration kinetics,impact of moisture and oxygen on CO_(2)working capacity,sorbent thermal properties,sorbent strength and attrition,and optimum particle-size distribution.This paper reports results from sorbent characterization testing and how these characteristics influenced the type and size of the CO_(2)-capture process equipment.In Part 2 of this work,results from tests of 1-MWe pilot-scale process equipment loaded with the sorbent described in Part 1 will be presented and analysed.
