Using the lumping method, CH_4, C_3H_8, C_10H_22, and C_22H_44 were chosen as themodel products, and CO as the key component. The mathematical model of a gas-solidfluidized bed reactor was established based on some hy...Using the lumping method, CH_4, C_3H_8, C_10H_22, and C_22H_44 were chosen as themodel products, and CO as the key component. The mathematical model of a gas-solidfluidized bed reactor was established based on some hypotheses. The consumption kinetic model of CO was investigated, and the parameters were estimated by UniversalGlobal Optimization with the Marquardt method. Residual error distribution and a statisticaltest show that the intrinsic kinetic models are reliable and acceptable. A model of carbonchain growth probability was established in terms of experiments. Coupled with the Ander-son- Schulz-Flory (ASF) distribution, the amount of specific product could be obtained.Large- scale cold model experiments were conducted to investigate the distribution of thegas (solid) phase and determine the function of the voidage with the location of the catalytic bed. The change tendencies of the components in the catalytic bed at different temperatures were computed and figured out. The calculated value computed by the modelestablished for the Fe-based F-T synthesis catalyst fit the experimental value very wellunder the same operating conditions, and all the absolute values of the relative deviationsare less than 5%.展开更多
Operability problem of dividing wall column (DWC) raised by vapor split was investigated by numerically analyzing four cases defined by different compositions of a three-component mixture. DWCs were firstly designed f...Operability problem of dividing wall column (DWC) raised by vapor split was investigated by numerically analyzing four cases defined by different compositions of a three-component mixture. DWCs were firstly designed for each case by optimizing the vapor split to the two sides of the dividing wall, and then their feasibilities and total annual costs in operation were evaluated against different vapor split ratios. The analysis on the operability of the DWC for four cases was made based on two scenarios: (1) vapor split is shifted by the vapor resistance difference between the column sections in the two sides of the dividing wall and (2) the feed composition is changed. It was demonstrated that the positioning of the dividing wall and the decision on the vapor split may affect significantly the operability of a DWC.展开更多
The distribution of electric field for the alignment and attachment of carbon nanotubes (CNTs) was simulated. To be attached at the desired place, the aligned and attracted CNTs should be stayed in the desired area ca...The distribution of electric field for the alignment and attachment of carbon nanotubes (CNTs) was simulated. To be attached at the desired place, the aligned and attracted CNTs should be stayed in the desired area called the stable region or the quasi-stable region for an instant where the change of electric field is minimized. Since the conical electrode has the very narrow sized quasi-stable region, few CNTs can be attached. The rectangular electrodes have a wide stable region, so lots of CNTs can be attached. The results indicate that the round electrode which has a proper sized quasi-stable region is more effective for aligning and attaching a single CNT than the conical or rectangular shaped electrodes.展开更多
基金Supported by the Doctoral Foundation of China (20050251006)
文摘Using the lumping method, CH_4, C_3H_8, C_10H_22, and C_22H_44 were chosen as themodel products, and CO as the key component. The mathematical model of a gas-solidfluidized bed reactor was established based on some hypotheses. The consumption kinetic model of CO was investigated, and the parameters were estimated by UniversalGlobal Optimization with the Marquardt method. Residual error distribution and a statisticaltest show that the intrinsic kinetic models are reliable and acceptable. A model of carbonchain growth probability was established in terms of experiments. Coupled with the Ander-son- Schulz-Flory (ASF) distribution, the amount of specific product could be obtained.Large- scale cold model experiments were conducted to investigate the distribution of thegas (solid) phase and determine the function of the voidage with the location of the catalytic bed. The change tendencies of the components in the catalytic bed at different temperatures were computed and figured out. The calculated value computed by the modelestablished for the Fe-based F-T synthesis catalyst fit the experimental value very wellunder the same operating conditions, and all the absolute values of the relative deviationsare less than 5%.
基金Supported by the State Key Fundamental Research Program(2012CB720500)
文摘Operability problem of dividing wall column (DWC) raised by vapor split was investigated by numerically analyzing four cases defined by different compositions of a three-component mixture. DWCs were firstly designed for each case by optimizing the vapor split to the two sides of the dividing wall, and then their feasibilities and total annual costs in operation were evaluated against different vapor split ratios. The analysis on the operability of the DWC for four cases was made based on two scenarios: (1) vapor split is shifted by the vapor resistance difference between the column sections in the two sides of the dividing wall and (2) the feed composition is changed. It was demonstrated that the positioning of the dividing wall and the decision on the vapor split may affect significantly the operability of a DWC.
基金Project supported by the Pusan National University Research GrantProject(2010-0008-276) supported by NCRC (National Core Research Center) through the National Research Foundation of Korea funded by the Ministry of Education, Science and Technology
文摘The distribution of electric field for the alignment and attachment of carbon nanotubes (CNTs) was simulated. To be attached at the desired place, the aligned and attracted CNTs should be stayed in the desired area called the stable region or the quasi-stable region for an instant where the change of electric field is minimized. Since the conical electrode has the very narrow sized quasi-stable region, few CNTs can be attached. The rectangular electrodes have a wide stable region, so lots of CNTs can be attached. The results indicate that the round electrode which has a proper sized quasi-stable region is more effective for aligning and attaching a single CNT than the conical or rectangular shaped electrodes.
