This paper presents the results from using a physical absorption process to absorb gaseous CO2mixed with N2using water by producing tiny bubbles via a liquid-film-forming device（LFFD）that improves the solubility of ...This paper presents the results from using a physical absorption process to absorb gaseous CO2mixed with N2using water by producing tiny bubbles via a liquid-film-forming device（LFFD）that improves the solubility of CO2in water.The influence of various parameters—pressure,initial CO2concentration,gas-to-liquid ratios,and temperature—on the CO2removal efficiency and its absorption rate in water were investigated and estimated thoroughly by statistical polynomial models obtained by the utilization of the response surface method（RSM）with a central composite design（CCD）.Based on the analysis,a high efficiency of CO2capture can be reached in conditions such as low pressure,high CO2concentration at the inlet,low gas/liquid ratio,and low temperature.For instance,the highest removal efficiency in the RSM–CCD experimental matrix of nearly 80%occurred for run number 20,which was conducted at 0.30 MPa,CO2concentration of 35%,gas/liquid ratio of 0.71,and temperature of 15℃.Furthermore,the coefficients of determination,R^2,were 0.996 for the removal rate and 0.982 for the absorption rate,implying that the predicted values computed by the constructed models correlate strongly and fit well with the experimental values.The results obtained provide essential information for implementing this method properly and effectively and contribute a promising approach to the problem of CO2capture in air pollution treatment.展开更多
An accurate prediction of the critical gas velocity for the liquid loading is of great importance for operators to select the tubing diameter for the newly drilled gas wells,or to optimize the production rate for prod...An accurate prediction of the critical gas velocity for the liquid loading is of great importance for operators to select the tubing diameter for the newly drilled gas wells,or to optimize the production rate for production wells.It is clear from previous experimental studies of the liquid entrainment rate in the gas core that the liquid is mainly carried in the form of film under the critical condition of the liquid loading onset.It is more reasonable to establish a mathematical model based on the film reversal rather than based on the droplet reversal.In our previous paper entitled“Prediction of the critical gas velocity of liquid unloading in the horizontal gas well”,a new analytical model was established based on the force balance between the gas-liquid interfacial friction force and the bottom film gravity,but the model is not very convenient to use because of the complexity of calculating the average film thickness.In the present study,a new method is proposed to calculate the average film thickness from the bubble drift velocity in the mixture,so the new analytical model becomes much easier to use.The new analytical model is evaluated against 103 sets of experimental data,the data in 124 vertical gas wells and one horizontal gas well.Meanwhile,the effect ofthe liquid loading on the production of the horizontal gas well is also analyzed.展开更多
基金the support of the Ministry of Education, Culture, Sports, Science, and Technology of Japan (MEXT – Monbukagakusho Scholarship)Yashima Environment Technology Foundation
文摘This paper presents the results from using a physical absorption process to absorb gaseous CO2mixed with N2using water by producing tiny bubbles via a liquid-film-forming device（LFFD）that improves the solubility of CO2in water.The influence of various parameters—pressure,initial CO2concentration,gas-to-liquid ratios,and temperature—on the CO2removal efficiency and its absorption rate in water were investigated and estimated thoroughly by statistical polynomial models obtained by the utilization of the response surface method（RSM）with a central composite design（CCD）.Based on the analysis,a high efficiency of CO2capture can be reached in conditions such as low pressure,high CO2concentration at the inlet,low gas/liquid ratio,and low temperature.For instance,the highest removal efficiency in the RSM–CCD experimental matrix of nearly 80%occurred for run number 20,which was conducted at 0.30 MPa,CO2concentration of 35%,gas/liquid ratio of 0.71,and temperature of 15℃.Furthermore,the coefficients of determination,R^2,were 0.996 for the removal rate and 0.982 for the absorption rate,implying that the predicted values computed by the constructed models correlate strongly and fit well with the experimental values.The results obtained provide essential information for implementing this method properly and effectively and contribute a promising approach to the problem of CO2capture in air pollution treatment.
基金supported by the National Natural Science Foundation of China(Grant No.No.51974263).
文摘An accurate prediction of the critical gas velocity for the liquid loading is of great importance for operators to select the tubing diameter for the newly drilled gas wells,or to optimize the production rate for production wells.It is clear from previous experimental studies of the liquid entrainment rate in the gas core that the liquid is mainly carried in the form of film under the critical condition of the liquid loading onset.It is more reasonable to establish a mathematical model based on the film reversal rather than based on the droplet reversal.In our previous paper entitled“Prediction of the critical gas velocity of liquid unloading in the horizontal gas well”,a new analytical model was established based on the force balance between the gas-liquid interfacial friction force and the bottom film gravity,but the model is not very convenient to use because of the complexity of calculating the average film thickness.In the present study,a new method is proposed to calculate the average film thickness from the bubble drift velocity in the mixture,so the new analytical model becomes much easier to use.The new analytical model is evaluated against 103 sets of experimental data,the data in 124 vertical gas wells and one horizontal gas well.Meanwhile,the effect ofthe liquid loading on the production of the horizontal gas well is also analyzed.
