采用强电离放电法降解废水中难降解有机物  

Non-thermal Oxygen Plasma Produced by a Strong Ionization Discharge and Its Application in Degrading Recalcitrant Organic Pollutants in Wastewater

作　　者：白敏菂[1] 冷白羽 陈宝玖[1] 

机构地区：[1]大连海事大学物理系,大连116026

出　　处：《高电压技术》2017年第8期2653-2659,共7页High Voltage Engineering

基　　金：国家自然科学基金(61371027;11374044);国家高技术研究发展计划(863计划)(2008AA06Z317)~~

摘　　要：为降解废水中难降解有机污染物,采用强电离放电将氧离解、电离成低温氧等离子体,并将其注入废水处理反应塔中,在反应塔中主要进行四步关键的等离子体反应。首先,低温氧等离子体中O_2^+与水分子反应生成微量·OH;然后,O_3与微量·OH反应形成高反应速率常数的过氧羟基自由基引发剂HO_2·;接着,高浓度O_3在引发剂HO_2·作用下生成氧化力强、反应速率很高的足量高浓度·OH;因此·OH将无选择、快速地将废水中难降解有机污染物降解成无害小分子有机物,最终矿化成CO_2、H_2O。实验结果表明:低温氧等离子体仅用2.5 min把废水中难降解有机污染物质量浓度从145.0 mg/L降至25.5 mg/L,去除率达到83.5%。与常规污水处理技术相比,采用强电离放电形成低温氧等离子体降解废水中难降解有机物方法具有设备投资和运行成本低以及污水处理系统简单等特点,将为受难降解有机物污染的废水回用提供一种经济、实用的新方法。A non-thermal oxygen plasma （O2＋ and O3） was produced by ionization and dissociation oxygen by a strong ionization discharge, and it was injected into a reaction tower of wastewater treatment for the degradation of recalcitrant organic pollutants in the wastewater. Four key plasma reactions took place in the reaction tower. Firstly, O2＋ among non-thermal oxygen plasma reacted with H20 molecule to form trace hydroxyl radicals （·OH）. Secondly, an initiator （HO2·） with high reaction rate constant was generated by O3 reacting with trace ·OH. And then, high concentration of ·OH with strong oxidizability and high reaction rate were formed by high concentration of O3 under the action of HO2·. So the -OH degraded recalcitrant organic pollutants into harmless small organic molecules non-selectively and rapidly. Finally ·OH mineralizes the small organic molecules into CO2 and H2O. The experimental results show that the degraded concentration by non-thermal oxygen plasma will decrease from 145.0 mg/L to 25.5 mg/L within just 25 minutes, and the removal rate will reach 83.5%. Compared with conventional sewage treatment method, the method of degradation recal- citrant organic pollutants in the wastewater with non-thermal oxygen plasma formed by a strong ionization discharge has lower operating costs and initial investment, and the sewage treatment system is more simple. The advantages wilt pro- vide an economic and practical new method for a deep-polluted wastewater reuse.

关 键 词：低温氧等离子体 深度降解 难降解有机污染物 废水 强电离放电 

分 类 号：X703[环境科学与工程—环境工程]