A compact pneumatic pulse-jet pump with a Venturi-like reverse flow diverter,which consists of a nozzle and diffuser,is designed for lifting and transporting a hazardous fluid through a narrow mounting hole.The pumpin...A compact pneumatic pulse-jet pump with a Venturi-like reverse flow diverter,which consists of a nozzle and diffuser,is designed for lifting and transporting a hazardous fluid through a narrow mounting hole.The pumping performance for a liquid mixture or a liquid-solid mixture is examined in terms of the effects of liquid viscosity,particle mass concentration,lifting height,and compression pressure.Results reveal that the pumping performance of the compact pneumatic pulse-jet pump is controlled by jet inertia and the flow resistance of the riser tube positioned after the diffuser.The capacity of the compact pneumatic pulse-jet pump increases with compression pressure and decreases with liquid viscosity.However,even for a liquid mixture with a high viscosity of 7.38 mPa·s,a pumping capacity of 170.7 L·h-1 was observed.For a liquid mixture,two dimensionless indices of performance were found to be the ratio of Euler numbers Euout/EuDV and the suction factor q.As the liquid-solid mixture was lifted to elevation of 6.74 m by the compact pump,the particle size distributions of the liquid-solid mixture in the tank and from the riser tube outlet were determined by a particle size analyzer and found to coincide well.展开更多
In this paper, a back propagation artificial neural network （BP-ANN） model is presented for the simultaneous estimation of vapour liquid equilibria （VLE） of four binary systems viz chlorodifluoromethan-carbondioxi...In this paper, a back propagation artificial neural network （BP-ANN） model is presented for the simultaneous estimation of vapour liquid equilibria （VLE） of four binary systems viz chlorodifluoromethan-carbondioxide, trifluoromethan-carbondioxide, carbondisulfied-trifluoromethan and carbondisulfied-chlorodifluoromethan. VLE data of the systems were taken from the literature for wide ranges of temperature （222.04-343.23K） and pressure （0.105 to 7.46MPa）. BP-ANN trained by the Levenberg-Marquardt algorithm in the MATLAB neural network toolbox was used for building and optimizing the model. It is shown that the established model could estimate the VLE with satisfactory precision and accuracy for the four systems with the root mean square error in the range of 0.054-0.119. Predictions using BP-ANN were compared with the conventional Redlich-Kwang-Soave （RKS） equation of state, suggesting that BP-ANN has better ability in estimation as compared with the RKS equation （the root mean square error in the range of 0.115-0.1546）.展开更多
CO2 gasification of Fuijian high-metamorphous anthracite with black liquor （BL） and/or mixture of BL and calcium stuff （BL＋Ca） as catalyst was studied by using a thermogravimetry under 750-950℃ at ambient pressu...CO2 gasification of Fuijian high-metamorphous anthracite with black liquor （BL） and/or mixture of BL and calcium stuff （BL＋Ca） as catalyst was studied by using a thermogravimetry under 750-950℃ at ambient pressure. When the coal was impregnated with an appropriate quantity of Ca and BL mixture, the catalytic activity of CO2 gasification was enhanced obviously. With a loading of 8%Na-BL＋2%Ca, the carbon conversion of three coal samples tested reaches up to 92.9%-99.3% at 950℃ within 30min. The continuous formation of alkali surface compounds such as （[-COM], [-CO2M]） and the presence of exchanged Ca, such as calcium phenolate and calcium carboxylates （COO）2Ca, contribute to the increase in catalytic efficiency, and using BL＋Ca is more efficient than that adding BL only, The homogeneous model and shrinking-core model were applied to correlate the data of conversion with time and to estimate the reaction rate constants under different temperature. The corresponding reaction activation energy （Ea） and pre-exponential factor of three anthracites were estimated. It is found that Ea is in the range from 73.6 to 121.4kJ·mol^-1 in the case of BL＋Ca, and 74.3 to 104.2kJ·mol^-1 when only BL was used as the catalyst, both of which are much less than that from 143.5 to 181.4kJ·mol^-1 if no catalyst used. It is clearly demonstrated that both of BL＋Ca mixture and BL could be the source of cheap and effective catalyst for coal gasification.展开更多
文摘A compact pneumatic pulse-jet pump with a Venturi-like reverse flow diverter,which consists of a nozzle and diffuser,is designed for lifting and transporting a hazardous fluid through a narrow mounting hole.The pumping performance for a liquid mixture or a liquid-solid mixture is examined in terms of the effects of liquid viscosity,particle mass concentration,lifting height,and compression pressure.Results reveal that the pumping performance of the compact pneumatic pulse-jet pump is controlled by jet inertia and the flow resistance of the riser tube positioned after the diffuser.The capacity of the compact pneumatic pulse-jet pump increases with compression pressure and decreases with liquid viscosity.However,even for a liquid mixture with a high viscosity of 7.38 mPa·s,a pumping capacity of 170.7 L·h-1 was observed.For a liquid mixture,two dimensionless indices of performance were found to be the ratio of Euler numbers Euout/EuDV and the suction factor q.As the liquid-solid mixture was lifted to elevation of 6.74 m by the compact pump,the particle size distributions of the liquid-solid mixture in the tank and from the riser tube outlet were determined by a particle size analyzer and found to coincide well.
文摘In this paper, a back propagation artificial neural network （BP-ANN） model is presented for the simultaneous estimation of vapour liquid equilibria （VLE） of four binary systems viz chlorodifluoromethan-carbondioxide, trifluoromethan-carbondioxide, carbondisulfied-trifluoromethan and carbondisulfied-chlorodifluoromethan. VLE data of the systems were taken from the literature for wide ranges of temperature （222.04-343.23K） and pressure （0.105 to 7.46MPa）. BP-ANN trained by the Levenberg-Marquardt algorithm in the MATLAB neural network toolbox was used for building and optimizing the model. It is shown that the established model could estimate the VLE with satisfactory precision and accuracy for the four systems with the root mean square error in the range of 0.054-0.119. Predictions using BP-ANN were compared with the conventional Redlich-Kwang-Soave （RKS） equation of state, suggesting that BP-ANN has better ability in estimation as compared with the RKS equation （the root mean square error in the range of 0.115-0.1546）.
基金Supported by the National Natural Science Foundation of China （No.20376014） and Fujian Science and Technology Council Grant （HG99-01）.
文摘CO2 gasification of Fuijian high-metamorphous anthracite with black liquor （BL） and/or mixture of BL and calcium stuff （BL＋Ca） as catalyst was studied by using a thermogravimetry under 750-950℃ at ambient pressure. When the coal was impregnated with an appropriate quantity of Ca and BL mixture, the catalytic activity of CO2 gasification was enhanced obviously. With a loading of 8%Na-BL＋2%Ca, the carbon conversion of three coal samples tested reaches up to 92.9%-99.3% at 950℃ within 30min. The continuous formation of alkali surface compounds such as （[-COM], [-CO2M]） and the presence of exchanged Ca, such as calcium phenolate and calcium carboxylates （COO）2Ca, contribute to the increase in catalytic efficiency, and using BL＋Ca is more efficient than that adding BL only, The homogeneous model and shrinking-core model were applied to correlate the data of conversion with time and to estimate the reaction rate constants under different temperature. The corresponding reaction activation energy （Ea） and pre-exponential factor of three anthracites were estimated. It is found that Ea is in the range from 73.6 to 121.4kJ·mol^-1 in the case of BL＋Ca, and 74.3 to 104.2kJ·mol^-1 when only BL was used as the catalyst, both of which are much less than that from 143.5 to 181.4kJ·mol^-1 if no catalyst used. It is clearly demonstrated that both of BL＋Ca mixture and BL could be the source of cheap and effective catalyst for coal gasification.
