ZHANG Yunpeng, XIE Hongyong

(School of Materials and Environmental Engineering, Shanghai Second Polytechnic University, Shanghai 201209，China)

Abstract: In order to further improve the feasibility of micro-bubbles in the treatment of black and odorous water, a pressurized dissolved air micro-bubbles generator was developed based on the principle of pressurized dissolved air flotation. The effects of gas-water volume ratio, pressure and water flow rate on the reactor performance were investigated. The effects of liquid surface position and surfactant on the size distribution, volume fraction and dissolved oxygen in water were studied, and the feasibility of the micro-bubbles generator was demonstrated. The experimental results show that: When P=0.4 MPa, gas-water ratio=1.5 ∶1 and QL=20 L/min, the minimum median diameter of micro bubbles is 34.65 μm and mass concentration of dissolved oxygen is 10.2 mg/L in water. Adding sodium dodecyl sulfate of 0.025 g/L, the minimum median diameter D50 of micro-bubbles was 26.68 μm under the same conditions, dissolved oxygen reached 11.1 mg/L. Dissolved oxygen in water remained about 7.5 mg/L after the equipment stopped running for 1 hour. In conclusion, pressurized micro-bubble generator can effectively increase dissolved oxygen in water, prolong the residence time of oxygen in water, and provide possibility for its application.

Keywords: micro-bubble generator; pressure dissolved air flotation; dissolved oxygen; surface active agent

中图分类号：X522

文献标志码：A

收稿日期： 2018-12-10，修回日期:2018-12-30，在线出版时间：2019-01-04 10:33。

基金项目：上海第二工业大学研究生项目，编号：EGD17YJ0037。

第一作者简介：张云鹏(1993—)，男，硕士研究生，研究方向为工业废水处理。E-mail：601250435@qq.com。

通信作者简介：谢洪勇(1961—)，男，教授，博士，研究方向为纳米材料和环境工程。E-mail：hyxie@sspu.edu.cn。