A multi-tube air-lift loop reactor (MT-ALR) is presented in this paper. Based on the energy conservation, a mathematical model describing the liquid circulation flow rate was developed, which was determined by gas vel...A multi-tube air-lift loop reactor (MT-ALR) is presented in this paper. Based on the energy conservation, a mathematical model describing the liquid circulation flow rate was developed, which was determined by gas velocity, the cross areas of riser and downcomer, gas hold-up and the local frictional loss coefficient. The experimental data indicate that either increase of gas flow rate or reduction of the downcomer diameter contributes to higher liquid circulation rate. The correlation between total and the local frictional loss coefficients was also established.Effects of gas flowrate in two risers and diameter of downcomer on the liquid circulation rate were examined. The value of total frictional loss coefficient was measured as a function of the cross area of downcomer and independent of the gas flow rate. The calculated results of liquid circulation rates agreed well with the experimental data with an average relative error of 9.6%.展开更多
A new type of multi-tube column, in which a novel internal-structure is installed in the bed of random packing, has been invented. The internal-structure reduces the hydraulic radius of the column and adjusts the gas/...A new type of multi-tube column, in which a novel internal-structure is installed in the bed of random packing, has been invented. The internal-structure reduces the hydraulic radius of the column and adjusts the gas/liquid flow so that the liquid maldistribution is greatly abated. A mathematical model with boundary conditions based on close-open mechanism at the internal-structure was established to study the hydraulic behavior of such a column and experiments were carded out to verify the applicability of the model. Predictions from the model agreed well with experimental results. The optimal ratio of the hydraulic diameter of the new multi-tube column to the packing element diameter is found to be 17.5 to 23.3 by employing the optimization method of nonlinear programming. And this new type of multi-tube column opens a new way for random packing columns to be scaled up for industry.展开更多
This paper tries to determine the economical type of reinforced concrete chimney structure based on the same effective height of chimney. The simulated experiments of wind tunnel are performed for the study, which com...This paper tries to determine the economical type of reinforced concrete chimney structure based on the same effective height of chimney. The simulated experiments of wind tunnel are performed for the study, which compare multi-tube chimney with single tube chimney based on the same buoyancy flux of plume. According to the comparison among the experiment results and the previous study of plume rise, the paper defines some final plume rise models. Finally, the paper gives the cost-benefit analysis after making cost estimation for different types of chimney structure and recommends the economical and reasonable type of chimney structure in light of the same environmental benefits.展开更多
基金Supported by Liaoning Provincial Natural Science Foundation(No.972050).
文摘A multi-tube air-lift loop reactor (MT-ALR) is presented in this paper. Based on the energy conservation, a mathematical model describing the liquid circulation flow rate was developed, which was determined by gas velocity, the cross areas of riser and downcomer, gas hold-up and the local frictional loss coefficient. The experimental data indicate that either increase of gas flow rate or reduction of the downcomer diameter contributes to higher liquid circulation rate. The correlation between total and the local frictional loss coefficients was also established.Effects of gas flowrate in two risers and diameter of downcomer on the liquid circulation rate were examined. The value of total frictional loss coefficient was measured as a function of the cross area of downcomer and independent of the gas flow rate. The calculated results of liquid circulation rates agreed well with the experimental data with an average relative error of 9.6%.
文摘A new type of multi-tube column, in which a novel internal-structure is installed in the bed of random packing, has been invented. The internal-structure reduces the hydraulic radius of the column and adjusts the gas/liquid flow so that the liquid maldistribution is greatly abated. A mathematical model with boundary conditions based on close-open mechanism at the internal-structure was established to study the hydraulic behavior of such a column and experiments were carded out to verify the applicability of the model. Predictions from the model agreed well with experimental results. The optimal ratio of the hydraulic diameter of the new multi-tube column to the packing element diameter is found to be 17.5 to 23.3 by employing the optimization method of nonlinear programming. And this new type of multi-tube column opens a new way for random packing columns to be scaled up for industry.
文摘This paper tries to determine the economical type of reinforced concrete chimney structure based on the same effective height of chimney. The simulated experiments of wind tunnel are performed for the study, which compare multi-tube chimney with single tube chimney based on the same buoyancy flux of plume. According to the comparison among the experiment results and the previous study of plume rise, the paper defines some final plume rise models. Finally, the paper gives the cost-benefit analysis after making cost estimation for different types of chimney structure and recommends the economical and reasonable type of chimney structure in light of the same environmental benefits.
