电化学氧化法处理高盐废水中盐酸土霉素的试验研究

Experimental study on treatment of oxytetracycline hydrochloride in high salinity wastewater by electrochemical oxidation

针对制药、精细化工等行业产生的高盐废水中盐酸土霉素含量高,难以生物降解的问题,构建基于钛基涂层二氧化锡掺锑网格阳极板的电化学氧化反应体系,考察操作条件、水质条件对降解效果的影响,并对比分析了在同样的极板面积、进水流量和反应时间下,单级反应与三级串联反应的处理效果与能耗。结果表明,电化学法可以有效降解废水中的盐酸土霉素,在盐度为20 g/L,极板间距为8 mm,电流密度为25.0 mA/cm^(2)的条件下,反应100 min时去除率可以达到100%;盐酸土霉素的初始浓度过高或者盐度过高均会导致去除率下降;相较于单级反应,三级串联连续流反应的盐酸土霉素去除率和电流效率更高,系统能耗更低。在电流密度为25.0 mA/cm^(2),反应时间为40 min的条件下,三级串联连续流反应对盐酸土霉素的去除率可达到84.7%,电流效率为71.9%,去除每千克有机物所需能耗为24.9 kW·h。

As the high salinity wastewater from pharmaceutical and fine chemical industry contains high concentration of oxytetracycline hydrochloride and is hard to be biodegraded,an electrochemical oxidation reaction system based on titanium-based coated tin dioxide doped with antimony grid anode plate was constructed.The influence of operating conditions and water quality on the degradation effect were investigated;besides,the treatment effect and energy consumption of single-stage reaction and three-stage series reaction under the same plate area,influent flow rate and reaction time conditions were compared and analyzed.The results showed that,oxytetracycline hydrochloride in wastewater could be effectively degraded by electrochemical method,and the removal rate reached 100%when the salt concentration was 20 g/L,the electrode spacing was 8 mm,the electric current density was 25.0 mA/cm^(2) and the reaction time was 100 min.Excessive initial concentration of oxytetracycline hydrochloride or excessive salinity will lead to the decrease of the removal rate;Compared to single-stage reaction,three-stage series continuous flow reaction has higher oxytetracycline hydrochloride removal rate and current efficiency,the energy consumption was lower.Under the condition that the electric current density was 25.0 mA/cm^(2),the reaction time was 40 min,the removal rate of oxytetracycline hygrochloride by three-stage series continuous flow reaction could reach 84.7%;the current efficiency was 71.9%and the energy consumption for organic substance removal was 24.9 kW·h/kg.