Abstract:

Separation performance of a sewage-hydrocyclone anti-blockage device consisting of a hydrocyclone and an ejector-reflux component was studied on sand-water and domestic sewage with various diameters of underflow pipe. Experimental results demonstrated that the hydrocyclone anti-blockage device with continuous underflow had higher separation efficiency but negligibly higher power consumption than conventional hydrocyclones with a closed "grit pot". Contrary to the Kelsall's conversion separation efficiency, a more comprehensive separation efficiency for the hydrocyclone anti-blockage device was proposed to include separation efficiency of the device and amount of available water for heat pump system. Under the optimum diameter of underflow pipe in the range of 5 mm and 10 mm, i.e., the optimum diameter ratio of the underflow pipe to the vortex finder between 12.5% and 25%, the sewage-hydrocyclone anti-blockage device had the separation efficiency of 92.6%-94.3% and the split ratio of 1.32%-2.54% for foulants of sizes < 4 mm in untreated domestic sewage. The split ratio was proportional to the underflow pipe diameter. Therefore, hydrocyclone separation could isolate foulants temporarily, clean water and recycle heat from sewage.

Key words: hydrocyclone, underflow pipe diameter, continuous underflow, waste water, recovery, multiphase flow

摘要：

为考察由旋流分离器和引射回流装置组成的污水旋流防阻机在不同底流管直径下的分离性能，进行了砂水分离实验和生活污水除污实验。实验结果显示：连续底流的旋流防阻机与封闭集污槽的旋流分离器相比，前者具有更高的分离效率，且能量损失增加基本可以忽略。相比Kelsall提出的折算分离效率，提出了更加适合旋流防阻机的综合考虑分离效率和热泵系统可用水量的综合分离效率。该旋流防阻机的最优底流管直径为5～10 mm，即最优底流管直径与溢流管直径比值为12.5%～25%。此时，污水旋流防阻机对原生生活污水中小于4 mm污杂物的分离效率为92.6%～94.3%，分流比为1.32%～2.54%。这说明通过旋流分离机制，可以达到污杂物暂离，净水取热的条件。另外，分流比与底流管直径呈正比。

关键词: 旋流分离器, 底流管直径, 连续底流, 废水, 回收, 多相流