水力空化去除水中难降解亲水性和疏水性污染物  

Degradation of refractory hydrophilic and hydrophobic pollutants by hydrodynamic cavitation

作　　者：张凯[1] 董志勇[1] 姚锐豪 

机构地区：[1]浙江工业大学水利与市政工程研究所,杭州310014

出　　处：《水力发电学报》2017年第8期50-57,共8页Journal of Hydroelectric Engineering

基　　金：国家自然科学基金(51179172)

摘　　要：利用自制的文丘里型、多孔板型及其组合式水力空化反应器,试验研究了水力空化对难降解亲水性污染物、疏水性污染物及其混合物去除效果的影响。重点研究了文丘里管的喉部相对长度对难降解疏水性污染物,以及多孔板三角形孔口的数量与大小对难降解亲水性污染物去除效果的影响,进一步采用文丘里管和三角形孔口多孔板的组合形式研究其对含亲、疏水性混合污染物的去除效果。结果表明:喉部相对长度为L/R=40时,疏水性污染物的降解率最高;适当地增加多孔板的孔口数量和减小孔径,有利于亲水性污染物的去除;文丘里管与孔口为棋盘式排列的多孔板组合是发生空化较优的水力条件。此外,提高流速,降低空化数,延长空化作用时间,选取适宜的废水初始浓度等,也有利于提高空化空蚀作用强度。The effect of hydrodynamic cavitation on removal of refractory hydrophilic and hydrophobic pollutants and their mixtures, using a self-developed hydrodynamic cavitation reactor composed of a Venturi tube, multi-orifice plates or their combinations, was studied experimentally and systemically. First, three types of Venturi tubes with different relative throat lengths were designed and tested, and their effects on the degradation rates ofhydrophobic pollutants were concluded. Then, four types of multi-orifice plates with checkerboard arrangement and staggered arrangement of triangular orifices were examined, and the effects of different numbers and sizes of the orifices on removal of hydrophilic pollutants were studied. Finally, combinations of Venturi tubes with multi-orifice plates were adopted to treat hydrophilic and hydrophobic mixtures, and their degradation rates were measured and compared. Our measurements show that relative throat length is a key factor in the degradation ofhydrophobic pollutants and has an optimal value ofL/R = 40. And increasing orifice number or reducing orifice size is favorable to degradation of hydrophilic pollutants, and a hydraulic condition for more effective cavitation can be achieved through combining a Venturi tube with the orifice plates of checkerboard arrangement. In addition, cavitation intensity can be improved by increasing flow velocity, reducing cavitation number, extending treatment time, or using suitable initial concentration of wastewater.

关 键 词：水力空化 文丘里管 多孔板 难降解污染物 

分 类 号：TV131.34[水利工程—水力学及河流动力学]