A three-stageflue gas hydrate-based desalination system was designed using liquefied natural gas(LNG)cold energy.This system could increase the CO_(2)amount-of-substance fraction in theflue gas from 17%to 97%and produce...A three-stageflue gas hydrate-based desalination system was designed using liquefied natural gas(LNG)cold energy.This system could increase the CO_(2)amount-of-substance fraction in theflue gas from 17%to 97%and produce desalinated water with a desalting rate of approximately 95%.Four system operating plans were simulated as follows:CO_(2)+N_(2)+seawater at 0.6 MPa,CO_(2)+N_(2)+seawater at 3 MPa,CO_(2)+N_(2)+tetra-n-butyl ammonium bromide(TBAB)+seawater at 0.6 MPa,and CO_(2)+N_(2)+tetrahydrofuran(THF)+seawater at 0.6 MPa.The energy consumption,LNG cold energy consumption,energy loss,and environmental friendliness were calculated and analyzed.The compression energy consumption was the highest contributor to the total energy consumption,and the highest percentage of total energy loss was heat exchange loss.Reducing the formation pressure in thefirst stage effectively reduced the total energy consumption,LNG cold energy consumption,and energy loss by 21.28%,24.41%,and 23.99%,respectively.Addition of TBAB/THF reduced the total energy consumption,LNG cold energy consumption,and energy loss by 18.45%/17.88%,32.30%/32.73%,and 24.65%/23.54%,respectively.The CO_(2)+CO_(2)+N_(2)+seawater operation at 0.6 MPa did not produce pollution.The CO_(2)+N_(2)+seawater operation at 3 MPa had the highest total energy consumption and LNG cold energy consumption.Operation with TBAB/THF had obvious advantages in terms of total energy consumption but suffered from the generation of pollution.Comprehensive analysis indicated that the CO_(2)+N_(2)+seawater operation at 0.6 MPa was the optimum system.展开更多
Interest in the possibility of storing and transporting natural gas in the form of clathrate hydrates has been increasing in recent years, particularly in some gas-importing and exporting countries.The technologies ne...Interest in the possibility of storing and transporting natural gas in the form of clathrate hydrates has been increasing in recent years, particularly in some gas-importing and exporting countries.The technologies necessary for realizing this possibility may be classified into those relevant to the four serial processes (a) the formation of a hydrate, (b) the processing (dewatering, pelletizing, etc. ) of the formed hydrate, (c) the storage and transportation of the processed hydrate, and (d) the regasification (dissociation) of the hydrate. The technological development of any of these processes is still at an early stage. For hydrate formation, for example, various rival operations have been proposed. However,many of them have never been subjected to actual tests for practical use. More efforts are required for examining the different hydrate-formation technologies and for rating them by comparison. The general design of the processing of the formed hydrate inevitably depends on both the hydrate-formation process and the storage/transportation process, hence it has a wide variability. The major uncertainty in the storage-process design lies in the as-yet unclarified utility of the "self-preservation" effect of the naturalgas hydrates. The process design as well as the relevant cost evaluation should strongly depend on whether the hydrates are well preserved at atmospheric pressure in large-scale storage facilities. The regasification process has been studied less extensively than the former processes. The state of the art of the technological development in each of the serial processes is reviewed, placing emphasis on the hydrate formation process.展开更多
The hydrate-based gas separation for capturing CO_(2)from flue gas has the characteristics of low energy consumption,simple operation and convenience for the subsequent CO_(2)storage and utilization.In order to reduce...The hydrate-based gas separation for capturing CO_(2)from flue gas has the characteristics of low energy consumption,simple operation and convenience for the subsequent CO_(2)storage and utilization.In order to reduce the total cumulative deviation of multi-stage hydration reaction,it is of great importance to establish an accurate thermodynamic model.Based on the vdW-P+CPA model,therefore,we refitted the parameters of the thermodynamic model considering the association between CO_(2)and H_(2)O.Firstly,the energy parameter a^(0.5) of H_(2)O and CO_(2)are developed as the cubic function and the linear function of[1-(T/Tc)^(0.5)],respectively.Then,the calculation parameters of Langmuir absorption coefficient of vdWeP model is refitted based on the temperature dependent binary interaction parameters kij.The following research results are obtained.First,when the novel fitted thermodynamic model is used to predict the density of saturated fluid,the average absolute deviation(AAD)of H_(2)O drops from 1.84%to 0.08%and that of CO_(2)drops from 4.06%to 2.09%.Second,when it is used to predict the phase equilibrium pressure of the hydrate generated from pure CO_(2)and pure N_(2),the AAD is 0.86%and 0.82%,respectively.Third,when it is used to calculate the phase equilibrium condition of hydrate generated from flue gas with different compositions,the AAD is decreased from 15.16%to 5.02%.In conclusion,this novel fitted thermodynamic model is of higher accuracy and it,to some extent,can decrease the total accumulative deviation of multi-stage hydration reaction.The research results provide reference for the actual application of the hydrate-based gas separation for capturing CO_(2)from flue gas.展开更多
Fundamental research and economic analysis of hydrate-based carbon dioxide(CO_(2))sequestration play a key role in developing the industrialization of oceanic CO_(2) sequestration.Therefore,this review deals with rece...Fundamental research and economic analysis of hydrate-based carbon dioxide(CO_(2))sequestration play a key role in developing the industrialization of oceanic CO_(2) sequestration.Therefore,this review deals with recent progress in hydrate-based CO_(2) sequestration from the thermodynamics and kinetics as well as their energy consumption and cost.The first section provides an overview of the thermodynamics of CO_(2) hydrate formation in both pure water and sea water,establishing a relationship between the enthalpy change of the hydrate formation reaction and the hydrate structure.Subsequently,a comparison of the kinetics of CO_(2) hydrate formation in pure water and sea water is presented,with further insight into the formation kinetics obtained through hydrate nucleation and growth models.The process of liquid CO_(2) forming hydrates is summarized,serving as a critical part of the fundamental research for oceanic CO_(2) sequestration.Finally,energy consumption and cost of CO_(2) capture methods are compared,and the whole sequestration process cost of CO_(2) capture-storage-transport-injection is comprehensively analyzed.The new understanding of this review is conducive to further commercial and industrial development of hydratebased CO_(2) sequestration.展开更多
基金funded by National Natural Science Foun-dation of China(52074165)Natural Science Foundation of Shandong Province(ZR2019ME116)Source Innovation Special Project of Qingdao West Coast New Area(2020-93).
文摘A three-stageflue gas hydrate-based desalination system was designed using liquefied natural gas(LNG)cold energy.This system could increase the CO_(2)amount-of-substance fraction in theflue gas from 17%to 97%and produce desalinated water with a desalting rate of approximately 95%.Four system operating plans were simulated as follows:CO_(2)+N_(2)+seawater at 0.6 MPa,CO_(2)+N_(2)+seawater at 3 MPa,CO_(2)+N_(2)+tetra-n-butyl ammonium bromide(TBAB)+seawater at 0.6 MPa,and CO_(2)+N_(2)+tetrahydrofuran(THF)+seawater at 0.6 MPa.The energy consumption,LNG cold energy consumption,energy loss,and environmental friendliness were calculated and analyzed.The compression energy consumption was the highest contributor to the total energy consumption,and the highest percentage of total energy loss was heat exchange loss.Reducing the formation pressure in thefirst stage effectively reduced the total energy consumption,LNG cold energy consumption,and energy loss by 21.28%,24.41%,and 23.99%,respectively.Addition of TBAB/THF reduced the total energy consumption,LNG cold energy consumption,and energy loss by 18.45%/17.88%,32.30%/32.73%,and 24.65%/23.54%,respectively.The CO_(2)+CO_(2)+N_(2)+seawater operation at 0.6 MPa did not produce pollution.The CO_(2)+N_(2)+seawater operation at 3 MPa had the highest total energy consumption and LNG cold energy consumption.Operation with TBAB/THF had obvious advantages in terms of total energy consumption but suffered from the generation of pollution.Comprehensive analysis indicated that the CO_(2)+N_(2)+seawater operation at 0.6 MPa was the optimum system.
文摘Interest in the possibility of storing and transporting natural gas in the form of clathrate hydrates has been increasing in recent years, particularly in some gas-importing and exporting countries.The technologies necessary for realizing this possibility may be classified into those relevant to the four serial processes (a) the formation of a hydrate, (b) the processing (dewatering, pelletizing, etc. ) of the formed hydrate, (c) the storage and transportation of the processed hydrate, and (d) the regasification (dissociation) of the hydrate. The technological development of any of these processes is still at an early stage. For hydrate formation, for example, various rival operations have been proposed. However,many of them have never been subjected to actual tests for practical use. More efforts are required for examining the different hydrate-formation technologies and for rating them by comparison. The general design of the processing of the formed hydrate inevitably depends on both the hydrate-formation process and the storage/transportation process, hence it has a wide variability. The major uncertainty in the storage-process design lies in the as-yet unclarified utility of the "self-preservation" effect of the naturalgas hydrates. The process design as well as the relevant cost evaluation should strongly depend on whether the hydrates are well preserved at atmospheric pressure in large-scale storage facilities. The regasification process has been studied less extensively than the former processes. The state of the art of the technological development in each of the serial processes is reviewed, placing emphasis on the hydrate formation process.
基金supported by the National Natural Science Foundation Project“Study on methane storage,separation and sequestration of carbon dioxide in exploitation and utilization of marine gas hydrate”(No.:21736005)China Postdoctoral Science Foundation Project(No.:2017M623060,2019T120860).
文摘The hydrate-based gas separation for capturing CO_(2)from flue gas has the characteristics of low energy consumption,simple operation and convenience for the subsequent CO_(2)storage and utilization.In order to reduce the total cumulative deviation of multi-stage hydration reaction,it is of great importance to establish an accurate thermodynamic model.Based on the vdW-P+CPA model,therefore,we refitted the parameters of the thermodynamic model considering the association between CO_(2)and H_(2)O.Firstly,the energy parameter a^(0.5) of H_(2)O and CO_(2)are developed as the cubic function and the linear function of[1-(T/Tc)^(0.5)],respectively.Then,the calculation parameters of Langmuir absorption coefficient of vdWeP model is refitted based on the temperature dependent binary interaction parameters kij.The following research results are obtained.First,when the novel fitted thermodynamic model is used to predict the density of saturated fluid,the average absolute deviation(AAD)of H_(2)O drops from 1.84%to 0.08%and that of CO_(2)drops from 4.06%to 2.09%.Second,when it is used to predict the phase equilibrium pressure of the hydrate generated from pure CO_(2)and pure N_(2),the AAD is 0.86%and 0.82%,respectively.Third,when it is used to calculate the phase equilibrium condition of hydrate generated from flue gas with different compositions,the AAD is decreased from 15.16%to 5.02%.In conclusion,this novel fitted thermodynamic model is of higher accuracy and it,to some extent,can decrease the total accumulative deviation of multi-stage hydration reaction.The research results provide reference for the actual application of the hydrate-based gas separation for capturing CO_(2)from flue gas.
基金Open access funding provided by South China University of Technologysupported by the Key Research and Development Program of Guangzhou(no.202206050002).
文摘Fundamental research and economic analysis of hydrate-based carbon dioxide(CO_(2))sequestration play a key role in developing the industrialization of oceanic CO_(2) sequestration.Therefore,this review deals with recent progress in hydrate-based CO_(2) sequestration from the thermodynamics and kinetics as well as their energy consumption and cost.The first section provides an overview of the thermodynamics of CO_(2) hydrate formation in both pure water and sea water,establishing a relationship between the enthalpy change of the hydrate formation reaction and the hydrate structure.Subsequently,a comparison of the kinetics of CO_(2) hydrate formation in pure water and sea water is presented,with further insight into the formation kinetics obtained through hydrate nucleation and growth models.The process of liquid CO_(2) forming hydrates is summarized,serving as a critical part of the fundamental research for oceanic CO_(2) sequestration.Finally,energy consumption and cost of CO_(2) capture methods are compared,and the whole sequestration process cost of CO_(2) capture-storage-transport-injection is comprehensively analyzed.The new understanding of this review is conducive to further commercial and industrial development of hydratebased CO_(2) sequestration.
