1. Experimental study on the reduction of sludge flowing resistance in pipe flow based on water film method.
- Author
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YU Li, CHEN Guang, ZHOU Piren, JI Hongxian, and DENG Wenyi
- Subjects
RHEOLOGY ,PIPE flow ,YIELD stress ,SHEARING force ,WATER temperature ,PIPE - Abstract
To solve the problem of high flow resistance of wet sludge pipeline, a rotary viscometer and a small self-made water film viscosity reduction device were used to explore the effects of the rheological properties of wet sludge, water-sludge ratio (WSR), wet sludge moisture content, wet sludge flow rate and water film temperature on water film viscosity reduction of wet sludge pipeline. The results show that the stress-time curve of wet sludge mainly goes through four stages, i.e. linear sharp increase stage, nonlinear increase stage, peak stage and gradual decrease stage. With the decrease of water content, the dynamic yield stress of wet sludge increases significantly. The greater the WSR, the more obvious the wet sludge pipeline viscosity reduction effect. When the WSR is 0.05, the viscosity reduction efficiency reaches 71.6% when the moisture content of wet sludge is 82.4% and the flow rate is 42.4 mL/min. When the WSR is 0.03, the turning point of viscosity reduction efficiency appears under these conditions. With the increase of wet sludge flow rate, the pipe shear stress and water film viscosity reduction amplitude increase, but the pipe shear stress increases more significantly, so the viscosity reduction rate decreases with the increase of wet sludge flow rate. Increasing water film temperature can improve the wet sludge viscosity reduction effect, and the lower the wet sludge moisture content, the more significant the improvement effect. Compared with water film at 18.5 °, the viscosity reduction of 70% wet sludge moisture content at 60.0 ° and WSR of 0.03 increases by 31.3%. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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