| 摘要: |
| 【目的】考察污泥在排污直管内的流动特性、管道压降及其阻力特性，为排污管道的设计提供参考。【方法】理论分析了直管内污泥流量的计算公式及管道输送沿程阻力系数，并在小型污泥流动试验系统上进行验证，同时利用污泥管道输送试验，就污泥流量、污泥含水率、排污管管径对排污直管内污泥流动阻力特性的影响进行了研究。【结果】在相同管径下，随着污泥流量的增加，管道压降逐渐增大，当流量平均增大到4～5 m3/h时，剪切应力破坏了污泥原有的结构，使其黏度降低，阻力系数逐渐趋于稳定；不同排污直管管径形成的流动阻力不同，当排污管直径从20 mm增大到32 mm时，管道压降从50 000～60 000 Pa/m降到10 000 Pa/m左右，降幅明显；污泥含水率越低，污泥在排污管中的停滞时间越长，污泥黏性就越高。【结论】污泥流量和管道输送沿程阻力系数计算值与试验值比较吻合，污泥的管道输送受排污管管径、污泥流量、含水率及停滞时间等因素的影响。 |
| 关键词: 污泥 管流法 管道压降 阻力特性 |
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| 基金项目:陕西省教育厅重点实验室科学研究计划项目（2010-12） |
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| Flow resistance test for sewage sludge in straight pipe |
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| Abstract: |
| 【Objective】This study inspected flow characteristics,pipeline pressure loss and resistance characteristics of sewage sludge in straight tube.【Method】The calculation formula and drag coefficient along the way of sewage sludge in straight pipe were theoretically analyzed and verified in a small slurry flow system.Then the effects of moisture content,straight pipe diameter on sewage sludge flow resistance characteristics were studied.【Result】Pressure losses increased as the increase of flow rate in pipe with same diameter.When the rate was 4-5 m3/h,shear stress broke the original structure of the sludge,reduced the viscosity and made the resistance coefficient stable.As the diameter increased from 20 mm to 60 mm,the pressure dropped from 50 000 to 60 000 to about 10 000 Pa/m,water content reduced,sludge residence time increased and viscosity increased.【Conclusion】The flow calculation formula and the drag coefficient were relatively consistent with the experimental value.Pipe transportation of sludge was influenced by pipe diameter,flow rate,water content,residence time and other factors. |
| Key words: sewage sludge pipe flow method pressure loss resistance characteristics |
