Bubble column reactors are multiphase contacting devices used in a wide variety of industrial application. Inrtevep S. A. is working on developing technologies to convert heavy and extra-heavy crude oil using this typ...Bubble column reactors are multiphase contacting devices used in a wide variety of industrial application. Inrtevep S. A. is working on developing technologies to convert heavy and extra-heavy crude oil using this type of reactors. Volumetric gas hold up, flow pattern, average gas bubble size, average interfacial area, RTD （residence time distribution）, dispersion coefficient, Peclet number are important design parameters for a proper scale up of them. Several cold model experiments have been proposed to determine the previously mentioned parameters at atmospheric conditions, using a plexiglas bubble column reactor at pilot plant scale unit （12 cm diameter）. It was also evaluated our own design of internal trays （plates） in the reactor. Air-tap water and air-light oil systems have been used. A wide operating condition range was applied, superficial gas velocity between 0.5-10 cm/s, liquid flowrate between 15-65 I/h. Generally speaking, working without internal trays was found that gas hold up increase along the reactor and it was possible to identify heterogeneous bubble, transition and turbulent flow pattern areas for the air-light oil system. Average gas bubble size increase along the reactor at bubble regime from 2-5 mm but at turbulent regime, stay oscillating between 1-3 mm. Average interfacial area increases exponentially with superficial gas velocity at any reactor height, till 1,412 m2/m3 for the air-light oil system but, at bubble flow regime, the average interfacial area is lower than 100 m2/m3, which negatively impact the reactor performance. Internal trays in the reactor always increase gas hold up at any condition or system used. Residence time distributions curves, Peclet numbers and dispersion coefficients founded, show that this reactor with this kind of design internal trays still tends to be a complete mixing reactor under the operating conditions used.展开更多
Since 2010, China＇s industrial economy has exhibited a stable growth pattern. Although industrial growth slowed, quality and efficiency showed improvement. In the post- crisis era, the growth rate and mechanism of Ch...Since 2010, China＇s industrial economy has exhibited a stable growth pattern. Although industrial growth slowed, quality and efficiency showed improvement. In the post- crisis era, the growth rate and mechanism of China＇s industries will take on some new features： First, the industrial economy will enter a stage of slow growth. Second, industrial upgrading will become the driver of industrial growth. Third, the boundary between sunrise and sunset industries will become blurred. Last but not least, industrial relocation will speed up. China＇s industrial operation is now facing ever-increasing challenges rather than favorable factors. Forecasts based on VAR and SARIMA models suggest that in 2011, China＇s industries will enter a slow growth stage at around 12.4 per cent. The central government should lower industrial growth expectations, speed up the technological upgrading of conventional industries, develop strategic emerging industries, and advance corporate mergers and restructuring.展开更多
webPDM Version 6.1 demonstrates Gerber Technology’s commitmentto enhance,support and maintain its Product Data Management(PDM) application Tolland,Connecticut,USA-Gerber Technology announces the
For a long time, the factors influencing a regional economic growth are mainly workforce, capital and scientific and technological progress. But with the further promotion of China＇s reform and opening-up and intensi...For a long time, the factors influencing a regional economic growth are mainly workforce, capital and scientific and technological progress. But with the further promotion of China＇s reform and opening-up and intensification of the further improvement degree, the main factors influencing a regional economic growth constantly change. This paper utilizes the relevant data of Sichuan to set up the econometric model and quantitatively studies the factors influencing economic growth of Sichuan. Through comparing the greatness that each factor influences the economic growth of Sichuan, the paper takes system changes as leading factor to influence the economic growth during 1984-2003 of Sichuan. At the same time, the upgrading of industrial structure will be a core of economic growth in the future, and the scientific and technological progress is the potential force of economic growth.展开更多
文摘Bubble column reactors are multiphase contacting devices used in a wide variety of industrial application. Inrtevep S. A. is working on developing technologies to convert heavy and extra-heavy crude oil using this type of reactors. Volumetric gas hold up, flow pattern, average gas bubble size, average interfacial area, RTD （residence time distribution）, dispersion coefficient, Peclet number are important design parameters for a proper scale up of them. Several cold model experiments have been proposed to determine the previously mentioned parameters at atmospheric conditions, using a plexiglas bubble column reactor at pilot plant scale unit （12 cm diameter）. It was also evaluated our own design of internal trays （plates） in the reactor. Air-tap water and air-light oil systems have been used. A wide operating condition range was applied, superficial gas velocity between 0.5-10 cm/s, liquid flowrate between 15-65 I/h. Generally speaking, working without internal trays was found that gas hold up increase along the reactor and it was possible to identify heterogeneous bubble, transition and turbulent flow pattern areas for the air-light oil system. Average gas bubble size increase along the reactor at bubble regime from 2-5 mm but at turbulent regime, stay oscillating between 1-3 mm. Average interfacial area increases exponentially with superficial gas velocity at any reactor height, till 1,412 m2/m3 for the air-light oil system but, at bubble flow regime, the average interfacial area is lower than 100 m2/m3, which negatively impact the reactor performance. Internal trays in the reactor always increase gas hold up at any condition or system used. Residence time distributions curves, Peclet numbers and dispersion coefficients founded, show that this reactor with this kind of design internal trays still tends to be a complete mixing reactor under the operating conditions used.
文摘Since 2010, China＇s industrial economy has exhibited a stable growth pattern. Although industrial growth slowed, quality and efficiency showed improvement. In the post- crisis era, the growth rate and mechanism of China＇s industries will take on some new features： First, the industrial economy will enter a stage of slow growth. Second, industrial upgrading will become the driver of industrial growth. Third, the boundary between sunrise and sunset industries will become blurred. Last but not least, industrial relocation will speed up. China＇s industrial operation is now facing ever-increasing challenges rather than favorable factors. Forecasts based on VAR and SARIMA models suggest that in 2011, China＇s industries will enter a slow growth stage at around 12.4 per cent. The central government should lower industrial growth expectations, speed up the technological upgrading of conventional industries, develop strategic emerging industries, and advance corporate mergers and restructuring.
文摘webPDM Version 6.1 demonstrates Gerber Technology’s commitmentto enhance,support and maintain its Product Data Management(PDM) application Tolland,Connecticut,USA-Gerber Technology announces the
文摘For a long time, the factors influencing a regional economic growth are mainly workforce, capital and scientific and technological progress. But with the further promotion of China＇s reform and opening-up and intensification of the further improvement degree, the main factors influencing a regional economic growth constantly change. This paper utilizes the relevant data of Sichuan to set up the econometric model and quantitatively studies the factors influencing economic growth of Sichuan. Through comparing the greatness that each factor influences the economic growth of Sichuan, the paper takes system changes as leading factor to influence the economic growth during 1984-2003 of Sichuan. At the same time, the upgrading of industrial structure will be a core of economic growth in the future, and the scientific and technological progress is the potential force of economic growth.
