This paper presents two novel conceptions in multi-stage hydrate separation technology for H 2+CH 4 system, i.e. the multi-stage equilibria adsorption and the reaction adsorption.It is assumed that there already exist...This paper presents two novel conceptions in multi-stage hydrate separation technology for H 2+CH 4 system, i.e. the multi-stage equilibria adsorption and the reaction adsorption.It is assumed that there already exists clathrate structure before the hydration reaction, and the hydration reaction is taken as gaseous adsorption in the crystal structure of hydrate.During the simulation of multi-stage equilibria adsorption, gases and water interact on every equilibrium stage till establishing full equilibria, wherein the gases that just entered one stage are in equilibrium with the liquid phase of the previous stage, and the water that just entered one stage is in equilibrium with the gas phase of the previous stage as well.A kinetic model of hydrate growth for methane is introduced into the reaction adsorption so that this simulation is closer to the reality.As hydrogen doesn’t react with water to form hydrate, the amount of hydrogen adsorption is calculated according to the proportion of methane and hydrogen adsorbed in the small cavities.Simultaneously, the plate column is employed as an example, where the gas-hydrate phase loads and hydrogen mole fraction are calculated by the multi-stage equilibria adsorption and reaction adsorption methods, and the results calculated by the two said methods are compared.展开更多
Three types of mine gas samples were used in the solutions of tetrahydrofuran(THF),sodium dodecyl sulfate(SDS)and THF-SDS with/without MMT respectively to investigate the effect of montmorillonite(MMT)on separation ch...Three types of mine gas samples were used in the solutions of tetrahydrofuran(THF),sodium dodecyl sulfate(SDS)and THF-SDS with/without MMT respectively to investigate the effect of montmorillonite(MMT)on separation characteristics of methane recovered from mine gas based on hydrate method.The partition coefficient,separation factor and recovery rate were used to evaluate the effects of MMT,and the selection factor was primarily proposed to define the selectivity of mine gas hydrate in the relative target gases.The experimental results indicate that MMT could improve the following factors including hydration separation factor,the selection factor,the partition coefficient,and the recovery rate.Furthermore,the effect of SDS on the function of MMT is analyzed in the process of hydration separation.Finally,due to the results of the experiment,it is concluded that MMT hydration mechanism explores the effect of MMT enrichment methane from mine gas.展开更多
A novel technology of preparation of felt-metal supported modified polyvinyl alcohol(PVA) ultrafiltration(UF) membrane was invented, which could avoid the blockage of the holes of support layer and the leakage of ...A novel technology of preparation of felt-metal supported modified polyvinyl alcohol(PVA) ultrafiltration(UF) membrane was invented, which could avoid the blockage of the holes of support layer and the leakage of the casting solution through the holes of support layer. Felt-metal supported ferric sulfate modified PVA composite UF membranes were prepared by the innovative technology. The results show that the composite membranes are used to treat 1 000 mg/L oil/water emulsion at trans-membrane pressure from 0.25 to 0.45 MPa, the permeate flux is from 36 to 52 L/(m2·h), and the retention of chemical oxygen demand(COD) is over 92%. The composite membrane resistance increases with the increase of trans-naembrane pressure.展开更多
文摘This paper presents two novel conceptions in multi-stage hydrate separation technology for H 2+CH 4 system, i.e. the multi-stage equilibria adsorption and the reaction adsorption.It is assumed that there already exists clathrate structure before the hydration reaction, and the hydration reaction is taken as gaseous adsorption in the crystal structure of hydrate.During the simulation of multi-stage equilibria adsorption, gases and water interact on every equilibrium stage till establishing full equilibria, wherein the gases that just entered one stage are in equilibrium with the liquid phase of the previous stage, and the water that just entered one stage is in equilibrium with the gas phase of the previous stage as well.A kinetic model of hydrate growth for methane is introduced into the reaction adsorption so that this simulation is closer to the reality.As hydrogen doesn’t react with water to form hydrate, the amount of hydrogen adsorption is calculated according to the proportion of methane and hydrogen adsorbed in the small cavities.Simultaneously, the plate column is employed as an example, where the gas-hydrate phase loads and hydrogen mole fraction are calculated by the multi-stage equilibria adsorption and reaction adsorption methods, and the results calculated by the two said methods are compared.
基金Projects(51404102,51334005,51274267)supported by the National Natural Science Foundation of ChinaProject(UNPYSCT-2017140)supported by the Youth Innovation Personnel Training in University and College of Heilongjiang Province,China
文摘Three types of mine gas samples were used in the solutions of tetrahydrofuran(THF),sodium dodecyl sulfate(SDS)and THF-SDS with/without MMT respectively to investigate the effect of montmorillonite(MMT)on separation characteristics of methane recovered from mine gas based on hydrate method.The partition coefficient,separation factor and recovery rate were used to evaluate the effects of MMT,and the selection factor was primarily proposed to define the selectivity of mine gas hydrate in the relative target gases.The experimental results indicate that MMT could improve the following factors including hydration separation factor,the selection factor,the partition coefficient,and the recovery rate.Furthermore,the effect of SDS on the function of MMT is analyzed in the process of hydration separation.Finally,due to the results of the experiment,it is concluded that MMT hydration mechanism explores the effect of MMT enrichment methane from mine gas.
文摘A novel technology of preparation of felt-metal supported modified polyvinyl alcohol(PVA) ultrafiltration(UF) membrane was invented, which could avoid the blockage of the holes of support layer and the leakage of the casting solution through the holes of support layer. Felt-metal supported ferric sulfate modified PVA composite UF membranes were prepared by the innovative technology. The results show that the composite membranes are used to treat 1 000 mg/L oil/water emulsion at trans-membrane pressure from 0.25 to 0.45 MPa, the permeate flux is from 36 to 52 L/(m2·h), and the retention of chemical oxygen demand(COD) is over 92%. The composite membrane resistance increases with the increase of trans-naembrane pressure.