Disinfection characteristics of an advanced rotational hydrodynamic cavitation reactor in pilot scale

Xun Sun; Zhengquan Wang; Xiaoxu Xuan; Li Ji; Xuewen Li; Yang Tao; Grzegorz Boczkaj; Shan Zhao; Joon Yong Yoon; Songying Chen

doi:10.1016/j.ultsonch.2021.105543

Disinfection characteristics of an advanced rotational hydrodynamic cavitation reactor in pilot scale

Ultrason Sonochem. 2021 May:73:105543. doi: 10.1016/j.ultsonch.2021.105543. Epub 2021 Apr 3.

Authors

Xun Sun¹, Zhengquan Wang², Xiaoxu Xuan³, Li Ji⁴, Xuewen Li⁵, Yang Tao⁶, Grzegorz Boczkaj⁷, Shan Zhao⁸, Joon Yong Yoon⁹, Songying Chen¹⁰

Affiliations

¹ Key Laboratory of High Efficiency and Clean Mechanical Manufacture, Ministry of Education, School of Mechanical Engineering, Shandong University, Jinan 250061, China; National Demonstration Center for Experimental Mechanical Engineering Education, Shandong University, Jinan 250061, China. Electronic address: xunsun@sdu.edu.cn.
² Key Laboratory of High Efficiency and Clean Mechanical Manufacture, Ministry of Education, School of Mechanical Engineering, Shandong University, Jinan 250061, China; National Demonstration Center for Experimental Mechanical Engineering Education, Shandong University, Jinan 250061, China. Electronic address: 202034380@mail.sdu.edu.cn.
³ Key Laboratory of High Efficiency and Clean Mechanical Manufacture, Ministry of Education, School of Mechanical Engineering, Shandong University, Jinan 250061, China; National Demonstration Center for Experimental Mechanical Engineering Education, Shandong University, Jinan 250061, China. Electronic address: xiaoxuxuan@sdu.edu.cn.
⁴ Key Laboratory of High Efficiency and Clean Mechanical Manufacture, Ministry of Education, School of Mechanical Engineering, Shandong University, Jinan 250061, China; National Demonstration Center for Experimental Mechanical Engineering Education, Shandong University, Jinan 250061, China. Electronic address: liji@sdu.edu.cn.
⁵ School of Public Health, Shandong University, Jinan 250061, China. Electronic address: lxw@sdu.edu.cn.
⁶ College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, China. Electronic address: yang.tao@njau.edu.cn.
⁷ Department of Process Engineering and Chemical Technology, Faculty of Chemistry, Gdańsk University of Technology, Gdańsk 80-233, Poland. Electronic address: grzegorz.boczkaj@pg.edu.pl.
⁸ Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China. Electronic address: szhao@sdu.edu.cn.
⁹ Department of Mechanical Engineering, Hanyang University, Ansan 15588, Republic of Korea. Electronic address: joyoon@hanyang.ac.kr.
¹⁰ Key Laboratory of High Efficiency and Clean Mechanical Manufacture, Ministry of Education, School of Mechanical Engineering, Shandong University, Jinan 250061, China; National Demonstration Center for Experimental Mechanical Engineering Education, Shandong University, Jinan 250061, China. Electronic address: chensy66@sdu.edu.cn.

Abstract

Hydrodynamic cavitation is a promising technique for water disinfection. In the present paper, the disinfection characteristics of an advanced hydrodynamic cavitation reactor (ARHCR) in pilot scale were studied. The effects of various flow rates (1.4-2.6 m³/h) and rotational speeds (2600-4200 rpm) on the removal of Escherichia coli (E. coli) were revealed and analyzed. The variation regularities of the log reduction and reaction rate constant at various cavitation numbers were established. A disinfection rate of 100% was achieved in only 4 min for 15 L of simulated effluent under 4200 rpm and 1.4 m³/h, with energy efficiency at 0.0499 kWh/L. A comprehensive comparison with previously introduced HCRs demonstrates the superior performance of the presented ARHCR system. The morphological changes in E. coli were studied by scanning electron microscopy. The results indicate that the ARHCR can lead to serious cleavage and surface damages to E. coli, which cannot be obtained by conventional HCRs. Finally, a possible damage mechanism of the ARHCR, including both the hydrodynamical and sonochemical effects, was proposed. The findings of the present study can provide strong support to the fundamental understanding and applications of ARHCRs for water disinfection.

Keywords: Disinfection mechanism; E. coli; Hydrodynamic cavitation; Sonochemistry; Water disinfection.