In order to enhance coalbed methane recovery, taking a self-developed largecalesimulation system for the platform, a modeling experiment of driving CH_4 by CO_2 gasinjection was studied.The results of experiment indic...In order to enhance coalbed methane recovery, taking a self-developed largecalesimulation system for the platform, a modeling experiment of driving CH_4 by CO_2 gasinjection was studied.The results of experiment indicates that there is a significant lag effectof adsorption and desorption on gas, the gas pressure is changed more rapidly in theprocess of carbon dioxide adsorption of coal than methane adsorption of coal; After theinjection of carbon dioxide, compare with methane single desorption.In an early stage,speed and amount of methane single desorption are greater than the speed and amountof displacement desorption, the speed and amount of displacement desorption becamegreater.In the process of replacement, CH_4 concentration constantly declined, while CO_2concentration constantly rose.In the process of CO_2 gas injection, the temperature of coalhave been significantly increased, it is more beneficial to make CH_4 gas molecules becomefree from the adsorbed state when temperature is increased.Under the pressurestep-down at the same rate, using the method of CO_2 driving CH_4, compared with themethod of conventional pressure step-down, the desorption rate of CH_4 in coal can beraised about 2.13 times, at the same time, a lot of greenhouse gas CO_2 will also be buriedin the ground, there is a very significant environmental benefit.展开更多
In this study, we provided more theoretical method for estimation of dissolution amount and applied this method to enhanced coalbed methane recovery (ECBMR) simulator. Dissolution amount was measured by method of di...In this study, we provided more theoretical method for estimation of dissolution amount and applied this method to enhanced coalbed methane recovery (ECBMR) simulator. Dissolution amount was measured by method of differential heat of adsorption. Akabira coal, a Japanese bituminous coal, was used for the experiment. The results showed that CO2 was stored in coal by both adsorption and dissolution. Using this result the methane production was calculated by ECBMR-simulator, enhanced coalbed methane recovery simulator, the University of Tokyo (ECOMERS-UT). Total stored CO2 was separated into adsorption component and dissolution component. Only the former component contributes to the competitive adsorption. Coalbed methane (CBM) production simulation considering the dissolution showed later and smaller peak production and prolonged methane production before the breakthrough than the conventional competitive adsorption.展开更多
文摘In order to enhance coalbed methane recovery, taking a self-developed largecalesimulation system for the platform, a modeling experiment of driving CH_4 by CO_2 gasinjection was studied.The results of experiment indicates that there is a significant lag effectof adsorption and desorption on gas, the gas pressure is changed more rapidly in theprocess of carbon dioxide adsorption of coal than methane adsorption of coal; After theinjection of carbon dioxide, compare with methane single desorption.In an early stage,speed and amount of methane single desorption are greater than the speed and amountof displacement desorption, the speed and amount of displacement desorption becamegreater.In the process of replacement, CH_4 concentration constantly declined, while CO_2concentration constantly rose.In the process of CO_2 gas injection, the temperature of coalhave been significantly increased, it is more beneficial to make CH_4 gas molecules becomefree from the adsorbed state when temperature is increased.Under the pressurestep-down at the same rate, using the method of CO_2 driving CH_4, compared with themethod of conventional pressure step-down, the desorption rate of CH_4 in coal can beraised about 2.13 times, at the same time, a lot of greenhouse gas CO_2 will also be buriedin the ground, there is a very significant environmental benefit.
文摘In this study, we provided more theoretical method for estimation of dissolution amount and applied this method to enhanced coalbed methane recovery (ECBMR) simulator. Dissolution amount was measured by method of differential heat of adsorption. Akabira coal, a Japanese bituminous coal, was used for the experiment. The results showed that CO2 was stored in coal by both adsorption and dissolution. Using this result the methane production was calculated by ECBMR-simulator, enhanced coalbed methane recovery simulator, the University of Tokyo (ECOMERS-UT). Total stored CO2 was separated into adsorption component and dissolution component. Only the former component contributes to the competitive adsorption. Coalbed methane (CBM) production simulation considering the dissolution showed later and smaller peak production and prolonged methane production before the breakthrough than the conventional competitive adsorption.