This paper analyzes the characteristics of a Natural Gas (NG)-based Methanol-Power Polygeneration System (MPPS). The structures and parameters of the polygeneration systems are investigated to explore the appropriate ...This paper analyzes the characteristics of a Natural Gas (NG)-based Methanol-Power Polygeneration System (MPPS). The structures and parameters of the polygeneration systems are investigated to explore the appropriate process for each polygeneration system. And some effective methods, such as exergy distribution analysis and energy-utilization diagrams (EUD) are adopted to investigate the performance & characteristic of the system. The results reveal that, MPPS adopted Partial Reforming and Partial Cycling synthesis (PR/PC) process can reach good performance, while MPPS exhibits poor performance when adopting Full Reforming and Once Through synthesis (FR/OT) process. Through further study with exergy analysis method, we find that the particular synthesis and separation properties of methanol lead to such difference. Therefore, the characteristics of chemical product should be important factors in the configuration and integration of polygeneration systems. The work of this paper is significant for the research and development of polygeneration system.展开更多
Polygeneration is a key strategy for making ultra clean energy products highly competitive with conventional energy systems. A polygeneration system based on coal gasification was analyzed using the exergy method ...Polygeneration is a key strategy for making ultra clean energy products highly competitive with conventional energy systems. A polygeneration system based on coal gasification was analyzed using the exergy method to calculate the system thermal efficiency. The results show that the polygeneration system has less pollutants and higher efficiency than the separate systems.展开更多
Biochar obtained from a biomass pyrolytic polygeneration technology exhibits great potential as an adsorbent,because of its renewability,porosity and desirable surface chemical properties.Pyrolysis temperature and fee...Biochar obtained from a biomass pyrolytic polygeneration technology exhibits great potential as an adsorbent,because of its renewability,porosity and desirable surface chemical properties.Pyrolysis temperature and feed are important elements in the preparation of biochar.Thus,the effects of these factors on the physicochemical properties of biochar were investigated in this study.The adsorption of biochar was evaluated using water,CO_(2),phenol,and methylene blue(MB)as adsorbates.The correlation between adsorption capacity and physicochemical properties was determined using the Pearson correlation.Results indicated that temperature could significantly affect the structure of biochar.The effects of biomass species were also noticeable as well.The number of macropores and their contribution to the total surface area for cotton stalk,bamboo,and rapeseed stalk increased with an increase in temperatures,meanwhile,the number of micropores decreased at high tem-peratures.At the same temperature,the macropore,mesopore,and micropore components of biochar produced by different species were markedly different.The water adsorption and CO_(2) adsorption of biochar were close to those of commercial activated carbon(AC),whereas the adsorption capacity of untreated biochar on phenol and MB was less than that of AC.Porosity exerted more significant effects on the adsorption capacity of biochar,compared with functional groups.The surface area of the micropores exhibited a significant positive correlation with the adsorption of CO_(2),phenol,and MB.The hydroxyl group was positively correlated with water adsorption.展开更多
On basis of adopting polygeneration systems for power and alternative fuels,capturing CO2 with near zero energy penalties,and storing CO2 on sites,a new kind of Energy Network can integrate energy utilization,CO2 capt...On basis of adopting polygeneration systems for power and alternative fuels,capturing CO2 with near zero energy penalties,and storing CO2 on sites,a new kind of Energy Network can integrate energy utilization,CO2 capture,transportation and storage synthetically.Techno-economic analysis of this solution focusing on Inner Mongolia and the Yangtze River Delta districts had been carried with comparison to the chain method for energy utilization and CO2 sequestration.This solution can save 21.5% of energy,and reduce 35% of total costs.The adoption of advanced polygeneration systems contributes 52.2% of the total saved costs,and the integration of energy utilization and CO2 sequestration in the Energy Network contributes 47.8%.From the aspect of CCS,the CO2 sequestration cost in the Energy Network can be as low as 12 $/t due to the lower energy penalties of capture in polygeneration systems and the combination of CO2 source and sink.The Energy Network exhibits attractive performance on energy saving,costs reduction for CCS,which may be a promising solution for sustainable development of China.展开更多
In this paper,a novel polygeneration system involving plasma gasifier,pyrolysis reactor,gas turbine(GT),supercritical CO_(2)(S-CO_(2))cycle,and organic Rankine cycle(ORC)has been developed.In the proposed scheme,the s...In this paper,a novel polygeneration system involving plasma gasifier,pyrolysis reactor,gas turbine(GT),supercritical CO_(2)(S-CO_(2))cycle,and organic Rankine cycle(ORC)has been developed.In the proposed scheme,the syngas is obtained by the gasification and the pyrolysis is first burned and drives the gas turbine for power generation,and then the resulting hot exhaust gas is applied to heat the working fluid for the supercritical CO_(2)cycle and the working fluid for the bottom organic Rankine cycle.In addition to the electrical output,the pyrolysis subsystem also produces pyrolysis oil and char.Accordingly,energy recovery is achieved while treating waste in a non-hazardous manner.The performance of the new scheme was examined by numerous methods,containing energy analysis,exergy analysis,and economic analysis.It is found that the net total energy output of the polygeneration system could attain 19.89 MW with a net total energy efficiency of 52.77%,and the total exergy efficiency of 50.14%.Besides,the dynamic payback period for the restoration of the proposed project is only 3.31 years,and the relative net present value of 77552640 USD can be achieved during its 20-year lifetime.展开更多
A novel solar polygeneration system for heat, power and fresh water production with absorption heat pump(AHP) and humidification-dehumidification(HDH) desalination system was proposed for high-efficiency utilization o...A novel solar polygeneration system for heat, power and fresh water production with absorption heat pump(AHP) and humidification-dehumidification(HDH) desalination system was proposed for high-efficiency utilization of solar energy. A case study of the proposed system was investigated based on 1 MW solar thermal power(STP) tower plant located in Beijing. Depending on mathematical modeling of the proposed system, corresponding modules were developed in TRNSYS. Meanwhile, control and operation strategies were fully studied with principal of solar energy cascade utilization. The thermodynamic performance of the proposed system was dynamically simulated at one minute intervals in a typical day. It was found that solar energy utilization level was improved with the help of solar thermal storage system and continuous heating in different operation modes met well with flexible heating loads from 93.76 kW to 169.49 kW. During AHP operation period, its Coefficient of Performance(COP) varied from 1.39 to 1.73 due to recoverable condensate heat restricted by heating demand. Meanwhile, fresh water production of HDH increased from 352.05 kg/h to 416.62 kg/h with Gained Output Ratio(GOR) increase from 2.48 to 2.67. Compared with original STP tower plant, maximum power generation efficiency was increased from 18.66% to 19.22% with power from 1169.69 kW to 1204.44 kW.展开更多
This study combines the thermodynamic analysis of a polygeneration system along with the numerical modelling of the thermal behavior of geothermal reservoirs in Mexico to exploit their energy.Each reservoir was modele...This study combines the thermodynamic analysis of a polygeneration system along with the numerical modelling of the thermal behavior of geothermal reservoirs in Mexico to exploit their energy.Each reservoir was modeled as a porous medium assuming a five-spot well configuration and local thermal equilibrium.The heat conduction-convection along with the Laplace equations were solved to compute temperature distributions,the useful life and the optimum distance between injection-extraction wells.The predicted temperature and pressure of the geothermal fluid at the outlet of the reservoir were exploited in the polygeneration system consisting of:(1)a Rankine cycle,(2)an absorption refrigeration cycle,and(3)a heat exchanger.The developed approach allows calculating both the optimal distance between injection-extraction wells and the global(utilization)efficiency of six arrangements(each composed by a reservoir connected to a polygeneration system)by assuming that reservoirs have a lifespan of 30 years.Results also show that:(a)due to the low efficiency of the Rankine cycle,very little thermal energy is converted into electrical one;(b)not only the temperature and the size are important when evaluating the power production performance of reservoirs,but also the permeability plays a fundamental role;(c)the first law efficiency of the polygeneration system ranges from 41.9%to 43.7%;(d)the utilization efficiency of the six arrangements lies in the range between 25.8%and 31%.展开更多
The sensitivity analysis of a polygeneration energy system fueled with duo fuel of coke oven gas and coal gas is performed in the study,and the focus is put on the relations among syngas composition,conversation rate ...The sensitivity analysis of a polygeneration energy system fueled with duo fuel of coke oven gas and coal gas is performed in the study,and the focus is put on the relations among syngas composition,conversation rate and performance.The impacts of the system configuration together with the fuel composition on the performance are investigated and discussed from the point of cascading utilization of fuel chemical energy.First,the main parameters affecting the performance are derived along with the analysis of the system configuration and the syngas composition.After the performance is being simulated by means of the Aspen Plus process simulator of version 11.1,the variation of the performance due to the composition of syngas and the conversion rate of chemical subsystem is obtained and discussed.It is obtained from the result that the proper conversion rate of the chemical subsystem according to the specific syngas composition results in better performance.And the syngas composition affects the optimal conversion rate of the chemical subsystem,the optimal point of which is around the stoichiometric composition for methanol production(CO/H_(2)=0.5).In all,the polygeneration system fueled with coke oven gas and coal gas,which can realize the reasonable conversion of syngas to power and chemical product according to the syngas composition,is a promising method for coal energy conversion and utilization.展开更多
This article briefly discusses the theoretical basis and overall goals of energy conservation in the steel manufacturing process system.It is proposed that in the process of implementing system energy conservation,it ...This article briefly discusses the theoretical basis and overall goals of energy conservation in the steel manufacturing process system.It is proposed that in the process of implementing system energy conservation,it is necessary to fully recognize and utilize the characteristics and functional advantages of the steel manufacturing process,pay more attention to energy quality,firmly grasp the overall goal of system optimization,focus on the integrated optimization of gas,steam,and waste heat systems,and propose the idea of constructing a"steel chemi-cal gas electricity heating cooling multi generation system".Based on practice,the main principles,models,and effects of implementing systematic energy conservation in steel enterprises have been proposed.展开更多
The residual gas and remained raw gas in dual gas resources polygeneration system are quite complex in components(mainly CH_(4),CO,and H_(2)),and these results to the distinguished differences in combustion reaction.E...The residual gas and remained raw gas in dual gas resources polygeneration system are quite complex in components(mainly CH_(4),CO,and H_(2)),and these results to the distinguished differences in combustion reaction.Experimental investigations on basic combustion characteristics of syngas referred above are conducted on a laboratory-scale combustor with flame temperature and flue gas composition measured and analyzed.Primary air coefficient(PA),total air coefficient(TA),and components of the syngas(CS)are selected as key factors,and it is found that PA dominates mostly the ignition of syngas and NOx formation,while TA affects the flue gas temperature after high temperature region and NOx formation trend to be positive as H_(2)/CO components increase.The results provide references for industrial utilization.展开更多
Solar energy is considered to be one of the most promising renewable and sustainable energy sources.The efficient utilization of solar energy has become a major requirement to build a clean and efficient energy system...Solar energy is considered to be one of the most promising renewable and sustainable energy sources.The efficient utilization of solar energy has become a major requirement to build a clean and efficient energy system and achieve the goal of carbon neutrality.The utilization of solar radiation mainly adopts two key technologies:concentrating photovoltaic(PV)and concentrated solar power(CSP).Currently,the cost of CSP with heat storage is about 9c/kWh(same as commercial PV systems)and is expected to drop to 5c/kWh by 2030.From a system level,this paper focuses on analyzing,a system for preparing clean solar fuel based on solar thermal fossil energy,the current mainstream concentrated solar thermal power generation system,the complementary utilization system coupled with multiple energy sources,and the efficient and economical multigeneration system.On the basis of this literature review,the key challenges and future development prospects for the application of concentrating solar energy systems are outlined.A concentrated solar utilization system needs to further improve efficiency and reduce costs in order to expand the scale and promote the market,it has far-reaching significance to achieve the goal of efficient utilization of clean fuel and solar energy.展开更多
文摘This paper analyzes the characteristics of a Natural Gas (NG)-based Methanol-Power Polygeneration System (MPPS). The structures and parameters of the polygeneration systems are investigated to explore the appropriate process for each polygeneration system. And some effective methods, such as exergy distribution analysis and energy-utilization diagrams (EUD) are adopted to investigate the performance & characteristic of the system. The results reveal that, MPPS adopted Partial Reforming and Partial Cycling synthesis (PR/PC) process can reach good performance, while MPPS exhibits poor performance when adopting Full Reforming and Once Through synthesis (FR/OT) process. Through further study with exergy analysis method, we find that the particular synthesis and separation properties of methanol lead to such difference. Therefore, the characteristics of chemical product should be important factors in the configuration and integration of polygeneration systems. The work of this paper is significant for the research and development of polygeneration system.
基金Supported by the Special Funds for Major State BasicResearch Projects ( No.G19990 2 2 3 0 4 ) and TRAPOYTof Mo E
文摘Polygeneration is a key strategy for making ultra clean energy products highly competitive with conventional energy systems. A polygeneration system based on coal gasification was analyzed using the exergy method to calculate the system thermal efficiency. The results show that the polygeneration system has less pollutants and higher efficiency than the separate systems.
基金The authors wish to express the great appreciation of the National Natural Science Foundation of China(51806077)the Fundamental Research Funds for the Central Universities(2020kfyXJJS071)the Foundation of State Key Laboratory of Coal Combustion(FSKLCCB2002).
文摘Biochar obtained from a biomass pyrolytic polygeneration technology exhibits great potential as an adsorbent,because of its renewability,porosity and desirable surface chemical properties.Pyrolysis temperature and feed are important elements in the preparation of biochar.Thus,the effects of these factors on the physicochemical properties of biochar were investigated in this study.The adsorption of biochar was evaluated using water,CO_(2),phenol,and methylene blue(MB)as adsorbates.The correlation between adsorption capacity and physicochemical properties was determined using the Pearson correlation.Results indicated that temperature could significantly affect the structure of biochar.The effects of biomass species were also noticeable as well.The number of macropores and their contribution to the total surface area for cotton stalk,bamboo,and rapeseed stalk increased with an increase in temperatures,meanwhile,the number of micropores decreased at high tem-peratures.At the same temperature,the macropore,mesopore,and micropore components of biochar produced by different species were markedly different.The water adsorption and CO_(2) adsorption of biochar were close to those of commercial activated carbon(AC),whereas the adsorption capacity of untreated biochar on phenol and MB was less than that of AC.Porosity exerted more significant effects on the adsorption capacity of biochar,compared with functional groups.The surface area of the micropores exhibited a significant positive correlation with the adsorption of CO_(2),phenol,and MB.The hydroxyl group was positively correlated with water adsorption.
基金supported by the National Basic Research Program of China ("973" Project) (Grant No.2005CB221207)the National Natural Science Foundation of China (Grant Nos.50520140517,50706052)
文摘On basis of adopting polygeneration systems for power and alternative fuels,capturing CO2 with near zero energy penalties,and storing CO2 on sites,a new kind of Energy Network can integrate energy utilization,CO2 capture,transportation and storage synthetically.Techno-economic analysis of this solution focusing on Inner Mongolia and the Yangtze River Delta districts had been carried with comparison to the chain method for energy utilization and CO2 sequestration.This solution can save 21.5% of energy,and reduce 35% of total costs.The adoption of advanced polygeneration systems contributes 52.2% of the total saved costs,and the integration of energy utilization and CO2 sequestration in the Energy Network contributes 47.8%.From the aspect of CCS,the CO2 sequestration cost in the Energy Network can be as low as 12 $/t due to the lower energy penalties of capture in polygeneration systems and the combination of CO2 source and sink.The Energy Network exhibits attractive performance on energy saving,costs reduction for CCS,which may be a promising solution for sustainable development of China.
基金supported by the National Natural Science Fund of China(No.52106008)Science Fund for Creative Research Groups of the National Natural Science Foundation of China(No.51821004)Science and Technology Planning Project of Guangdong Province(No.2020B1212060048).
文摘In this paper,a novel polygeneration system involving plasma gasifier,pyrolysis reactor,gas turbine(GT),supercritical CO_(2)(S-CO_(2))cycle,and organic Rankine cycle(ORC)has been developed.In the proposed scheme,the syngas is obtained by the gasification and the pyrolysis is first burned and drives the gas turbine for power generation,and then the resulting hot exhaust gas is applied to heat the working fluid for the supercritical CO_(2)cycle and the working fluid for the bottom organic Rankine cycle.In addition to the electrical output,the pyrolysis subsystem also produces pyrolysis oil and char.Accordingly,energy recovery is achieved while treating waste in a non-hazardous manner.The performance of the new scheme was examined by numerous methods,containing energy analysis,exergy analysis,and economic analysis.It is found that the net total energy output of the polygeneration system could attain 19.89 MW with a net total energy efficiency of 52.77%,and the total exergy efficiency of 50.14%.Besides,the dynamic payback period for the restoration of the proposed project is only 3.31 years,and the relative net present value of 77552640 USD can be achieved during its 20-year lifetime.
基金This study was supported by the International Partnership Program of Chinese Academy of Sciences(CAS,Grant No.182111KYSB20160005)the National Nature Science Foundation of China(Grant No.51476164).
文摘A novel solar polygeneration system for heat, power and fresh water production with absorption heat pump(AHP) and humidification-dehumidification(HDH) desalination system was proposed for high-efficiency utilization of solar energy. A case study of the proposed system was investigated based on 1 MW solar thermal power(STP) tower plant located in Beijing. Depending on mathematical modeling of the proposed system, corresponding modules were developed in TRNSYS. Meanwhile, control and operation strategies were fully studied with principal of solar energy cascade utilization. The thermodynamic performance of the proposed system was dynamically simulated at one minute intervals in a typical day. It was found that solar energy utilization level was improved with the help of solar thermal storage system and continuous heating in different operation modes met well with flexible heating loads from 93.76 kW to 169.49 kW. During AHP operation period, its Coefficient of Performance(COP) varied from 1.39 to 1.73 due to recoverable condensate heat restricted by heating demand. Meanwhile, fresh water production of HDH increased from 352.05 kg/h to 416.62 kg/h with Gained Output Ratio(GOR) increase from 2.48 to 2.67. Compared with original STP tower plant, maximum power generation efficiency was increased from 18.66% to 19.22% with power from 1169.69 kW to 1204.44 kW.
文摘This study combines the thermodynamic analysis of a polygeneration system along with the numerical modelling of the thermal behavior of geothermal reservoirs in Mexico to exploit their energy.Each reservoir was modeled as a porous medium assuming a five-spot well configuration and local thermal equilibrium.The heat conduction-convection along with the Laplace equations were solved to compute temperature distributions,the useful life and the optimum distance between injection-extraction wells.The predicted temperature and pressure of the geothermal fluid at the outlet of the reservoir were exploited in the polygeneration system consisting of:(1)a Rankine cycle,(2)an absorption refrigeration cycle,and(3)a heat exchanger.The developed approach allows calculating both the optimal distance between injection-extraction wells and the global(utilization)efficiency of six arrangements(each composed by a reservoir connected to a polygeneration system)by assuming that reservoirs have a lifespan of 30 years.Results also show that:(a)due to the low efficiency of the Rankine cycle,very little thermal energy is converted into electrical one;(b)not only the temperature and the size are important when evaluating the power production performance of reservoirs,but also the permeability plays a fundamental role;(c)the first law efficiency of the polygeneration system ranges from 41.9%to 43.7%;(d)the utilization efficiency of the six arrangements lies in the range between 25.8%and 31%.
基金supported by the National Natural Science Foundation of China(Grant No.50706052)the State Key Development Program for Basic Research of China(Grant No.2005CB221207).
文摘The sensitivity analysis of a polygeneration energy system fueled with duo fuel of coke oven gas and coal gas is performed in the study,and the focus is put on the relations among syngas composition,conversation rate and performance.The impacts of the system configuration together with the fuel composition on the performance are investigated and discussed from the point of cascading utilization of fuel chemical energy.First,the main parameters affecting the performance are derived along with the analysis of the system configuration and the syngas composition.After the performance is being simulated by means of the Aspen Plus process simulator of version 11.1,the variation of the performance due to the composition of syngas and the conversion rate of chemical subsystem is obtained and discussed.It is obtained from the result that the proper conversion rate of the chemical subsystem according to the specific syngas composition results in better performance.And the syngas composition affects the optimal conversion rate of the chemical subsystem,the optimal point of which is around the stoichiometric composition for methanol production(CO/H_(2)=0.5).In all,the polygeneration system fueled with coke oven gas and coal gas,which can realize the reasonable conversion of syngas to power and chemical product according to the syngas composition,is a promising method for coal energy conversion and utilization.
文摘This article briefly discusses the theoretical basis and overall goals of energy conservation in the steel manufacturing process system.It is proposed that in the process of implementing system energy conservation,it is necessary to fully recognize and utilize the characteristics and functional advantages of the steel manufacturing process,pay more attention to energy quality,firmly grasp the overall goal of system optimization,focus on the integrated optimization of gas,steam,and waste heat systems,and propose the idea of constructing a"steel chemi-cal gas electricity heating cooling multi generation system".Based on practice,the main principles,models,and effects of implementing systematic energy conservation in steel enterprises have been proposed.
基金supported by the National Basic Research Program of China(No.2005CB221206).
文摘The residual gas and remained raw gas in dual gas resources polygeneration system are quite complex in components(mainly CH_(4),CO,and H_(2)),and these results to the distinguished differences in combustion reaction.Experimental investigations on basic combustion characteristics of syngas referred above are conducted on a laboratory-scale combustor with flame temperature and flue gas composition measured and analyzed.Primary air coefficient(PA),total air coefficient(TA),and components of the syngas(CS)are selected as key factors,and it is found that PA dominates mostly the ignition of syngas and NOx formation,while TA affects the flue gas temperature after high temperature region and NOx formation trend to be positive as H_(2)/CO components increase.The results provide references for industrial utilization.
基金the financial support from the National Key R&D Plan Intergovernmental International Science and Technology Innovation Cooperation Project(grant no.2019YFE0109700)the Foshan Science and Technology Innovation Team(grant no.1920001000052).
文摘Solar energy is considered to be one of the most promising renewable and sustainable energy sources.The efficient utilization of solar energy has become a major requirement to build a clean and efficient energy system and achieve the goal of carbon neutrality.The utilization of solar radiation mainly adopts two key technologies:concentrating photovoltaic(PV)and concentrated solar power(CSP).Currently,the cost of CSP with heat storage is about 9c/kWh(same as commercial PV systems)and is expected to drop to 5c/kWh by 2030.From a system level,this paper focuses on analyzing,a system for preparing clean solar fuel based on solar thermal fossil energy,the current mainstream concentrated solar thermal power generation system,the complementary utilization system coupled with multiple energy sources,and the efficient and economical multigeneration system.On the basis of this literature review,the key challenges and future development prospects for the application of concentrating solar energy systems are outlined.A concentrated solar utilization system needs to further improve efficiency and reduce costs in order to expand the scale and promote the market,it has far-reaching significance to achieve the goal of efficient utilization of clean fuel and solar energy.
