Impacts on flow resistance and physicochemical property of coal water slurry by ultrasonic irradiation

被引：0

作者：

Cheng, Jun ^{[1
]}

Zhou, Jun-Hu ^{[1
]}

Li, Yan-Chang ^{[2
]}

Liu, Jian-Zhong ^{[1
]}

Cen, Ke-Fa ^{[1
]}

机构：

[1] State Key Laboratory of Clean Energy Utilization, Zhejiang University

[2] College of Safety Science and Engineering, Liaoning Technical University

来源：

Zhejiang Daxue Xuebao (Gongxue Ban)/Journal of Zhejiang University (Engineering Science) | 2008年 / 42卷 / 06期

关键词：

Coal water slurry; Flow resistance; Granularity; Ultrasonic; Viscosity;

D O I：

10.3785/j.issn.1008-973X.2008.06.020

中图分类号：

学科分类号：

摘要：

The impacts of ultrasonic irradiation with different powers on flow resistance of coal water slurry (CWS) with different viscosities and velocities were investigated. The effects of ultrasonic irradiation with different frequencies on the particle size, viscosity and stability of CWS were also studied. When the ultrasonic power density was 0.49 W/cm2, the CWS viscosity was 245 mPa·s and the flow velocity was 0.27 m/s, the flow resistance was dramatically reduced by 49.4%. The CWS flow resistance firstly decreased to an optimal valley and then contrarily increased with increasing ultrasonic power density. The reduction effect in CWS flow resistance caused by ultrasonic irradiation was weakened with increasing CWS viscosity and flow velocity. Considering the CWS property improvement and low energy comsumption, the ultrasonic frequency of 10 kHz and irradiation time of 1 min were optimal conditions in CWS preparation. The average granularities of the conventional and ultrafine CWS both decrease with ultrasonic irradiation, while both CWS present the pseudo plastic characteristics. The ultrasonic irradiation resulted in an evident increase in CWS viscosity at low shear rate (11.7/s) and a slight decrease in CWS viscosity at high shear rate (110/s). The results imply that the CWS stability in storage and transportation was improved, as well as the CWS atomization in high-speed spraying through nozzles.

引用

页码：998 / 1004

页数：6

共 14 条

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