Carrousel氧化沟的流动特性研究

Study on flow characteristic of Carrousel oxidation ditch

采用颗粒动态分析仪(PDA)对倒伞形表面曝气机曝气的Carrousel小试氧化沟进行测试,得出了氧化沟内较系统的流动特性参数。比较了固液两相在氧化沟内流动的差别,发现固液两相流动速度差别较小,由于惯性的影响,固相的沉降速度略大于液相。考察了表曝机的转速、表曝机相对于液面的位置、氧化沟的深度等因素对氧化沟内流动的影响,随着表曝机转速的增大和表曝机浸入液面深度的增加,流动速度和沉降速度均会增大,而氧化沟深度增加时,距离液面同一深度处的速度则会减小。实验结果与污水处理厂的实际情形进行比较发现,二者变化趋势一致,说明本实验结果可用于指导工程实际,为氧化沟的优化设计提供依据。

The flow in an experimental Carrousel oxidation ditch with two surface aerators like inverse umbrella was measured with particle dynamic analyser （PDA）. It was observed that there was negligible difference between the flow velocities of solid and liquid phases, while the settling velocity of solid was a bit larger than that of liquid due to inertial effect. The influences of the speed of aerators, the location of aerators relative to the surface and the height of the oxidation ditch were investigated. With the increasing of aerator speed, the velocity came up. The deeper the aerators in the liquid, the larger the velocity. When the oxidation ditch was higher, the velocity at the same location below the surface would decrease. The experimental results were also compared with those obtained in a wastewater treatment plant of Huaibei city. They were in good agreement. This gives evidence that the experimental results presented in this paper could be used for practice. All these results will play significant roles in the design and optimization of oxidation ditch.