Time filter

Source Type

ZHOU G.,Wenzhou Great Wall Mixer Design Institute | XIE M.,Wenzhou Great Wall Mixer Design Institute | XIE M.,East China University of Science and Technology | LIU M.,China National Offshore Oil Corporation | And 3 more authors.
Chinese Journal of Chemical Engineering | Year: 2010

Enhanced oil recovery (EOR) by means of polymer flooding is an important technology for the strategic development of offshore oilfields in China. Hydrophobically associating polyacrylamide (HAPAM) has been recently proposed as a new flooding agent. The solubility of HAPAM is low, which is the bottleneck for further improving the oil recovery through polymer flooding in offshore oilfield. Stirred tanks have been used on offshore platforms to enhance HAPAM dissolving. But there is little literature on the study of HAPAM dissolving characteristics in stirred tanks. In this paper, effects of temperature, salinity, stirring speed, impeller type and stirring method on the dissolution of HAPAM are reported. The experimental results manifest that the dissolving rate of HAPAM increases with temperature and stirring speed, but the viscosity of the polymer solution decreases. There is an optimal range of salinity for polymer dissolving. Combining the operation mode of up-pumping with varying stirring speed, hydrofoil impeller can accelerate the dissolution of HAPAM and maintain a high solution viscosity. © 2010 Chemical Industry and Engineering Society of China (CIESC) and Chemical Industry Press (CIP).


Xie M.-H.,East China University of Science and Technology | Xia J.-Y.,East China University of Science and Technology | Zhou Z.,East China University of Science and Technology | Zhou G.-Z.,Wenzhou Great Wall Mixer Design Institute | And 4 more authors.
Chemical Engineering Science | Year: 2014

Mass transfer and mixing performances are very critical for xanthan gum fermentation process. Power consumption, local and average volumetric mass transfer coefficient (kLa) were compared for six impeller combinations in a 50L perspex tank with xanthan gum solutions. Impellers used in various combinations can be distinguished as two categories: "small-diameter" impeller, which include Rushton turbine, hollow blade turbine and wide-blade hydrofoil impeller and "large-diameter" including ellipse gate impeller, Intermig and double helical ribbon. The results show that in order to gain the same power input, the rotating speed of "small-diameter" impeller combinations increases as the concentration of xanthan gum increases, while it decreases for "large-diameter" impeller combinations. The two categories also show distinguished mass transfer rates. For the "small-diameter" impeller combinations, the kLa values near the wall region drop faster than that in other areas as the concentration of xanthan gum increases. While for the "large-diameter" impeller combinations, the distribution of kLa is homogenous except in the bottom area but with poor gas dispersion capabilities as concentration of xanthan gum increases. The averaged kLa for each impller combination was correlated well with the specific gassed power input, superficial gas velocity and effective viscosity. The obtained correlation shows that the kLa strongly depends on specific power input and viscosity, but is less influenced by the gas flow rate. © 2013 Elsevier Ltd.


Xie M.-H.,East China University of Science and Technology | Xia J.-Y.,East China University of Science and Technology | Zhou G.-Z.,Wenzhou Great Wall Mixer Design Institute | Zhang S.-L.,East China University of Science and Technology | Yu P.-Q.,Wenzhou Great Wall Mixer Design Institute
Chemical Engineering and Technology | Year: 2013

Hydrodynamics characteristics like flow pattern, shear rate distribution, power consumption, axial pumping capacity, mixing time, and mixing efficiency of an ellipse gate (EG) impeller were investigated by experimental and numerical methods. The numerical simulation results were validated by experimental data of power consumption and mixing time. Results indicate that the axial pumping number of the EG impeller is larger than that of any other reported large-scale impeller under laminar regime, and that the shear rate formed by this impeller is less sensitive to Reynolds numbers. In-depth analysis reveals the different function of each part of the EG impeller under different flow regimes. This impeller provides an almost similar mixing efficiency like the double-helical ribbon impeller under laminar regime, but much higher mixing efficiency both under transitional and turbulent flow regimes. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Xie M.-H.,East China University of Science and Technology | Xie M.-H.,Wenzhou Great Wall Mixer Design Institute | Zhou G.-Z.,Wenzhou Great Wall Mixer Design Institute | Xia J.-Y.,East China University of Science and Technology | And 3 more authors.
Journal of Chemical Engineering of Japan | Year: 2011

Power numbers in a baffled stirring tank with paddle-type impellers were measured over a range of Reynolds numbers, from laminar- to turbulent-flow regions. The impellers studied included a two-blade flat-paddle impeller, a 45° two-blade pitched-paddle impeller, a 45° four-blade pitched-blade turbine, and a two-stage pitchedblade turbine. The impeller-diameter-to-tank-diameter ratio was 0.5 to 0.6. The measured power numbers were compared with those derived from two other methods: prediction by using correlations and computational fluid dynamics (CFD). Power number correlations showed that the values estimated from the empirical correlations proposed by Nagata agreed closely with those measured in the laminar-flow region but deviated significantly in the transitional- and turbulent-flow regions. The power numbers derived from the correlation proposed by Kamei and Hiraoka agreed well with the experimental results in the laminar- and turbulent-flow regions. The power number in a stirring tank was also simulated by the CFD method. The numerical results showed satisfactory agreement with the experimental data over a wide range of Reynolds numbers. © 2011 The Society of Chemical Engineers, Japan.

Loading Wenzhou Great Wall Mixer Design Institute collaborators
Loading Wenzhou Great Wall Mixer Design Institute collaborators