藻类对摇蚊幼虫生成消毒副产物的影响规律

Effect of Algae on Disinfection By-products Formation by Chironomid Larvae IOM

以摇蚊幼虫和铜绿微囊藻胞内有机物(IOM)为研究对象,考察在不同铜绿微囊藻和摇蚊幼虫浓度、氯胺投加量、反应时间、p H值和温度等条件下消毒副产物的生成规律。结果表明,当铜绿微囊藻或摇蚊幼虫单独存在时消毒副产物生成量都很少,最大值不超过1.3μg/L;当二者共存时,氯胺消毒副产物生成量均有明显增加,但变化趋势却有所不同。随着TOC浓度的不断增大,具有稳定结构的消毒副产物,如三氯甲烷(TCM)和三氯乙酸(TCAA)的生成量逐渐增加,水合氯醛(CH)和二氯丙酮(DCP)生成量则是先增加再降低。随着氯胺投量的增加,TCM、二氯乙腈(DCAN)、CH、DCP、二氯乙酸(DCAA)和TCAA生成量都逐渐增加。CH和DCP生成量随反应时间的延长先增加后减少,在48 h时生成量最多。p H值的增大有利于增加TCM和TCAA的生成量。DCAN生成量随着温度的升高而减少,CH和DCP生成量在20℃时出现最大值,分别为1.43和1.22μg/L。

Taking intracellular organic matter （IOM） of chironomid larvae and Microcystis aeruginosa as the research object, the formation of disinfection by-products （DBPs） under different concentrations of Microcystis aeruginosa and chironomid larvae, chloramine dosages, reaction times, pH values and temperatures was investigated. The results showed that when Microcystis aeruginosa or chironomid larvae existed alone, the concentrations of DBPs were all low, and the maximum value was less than 1.3 μg/L. When Microcystis aeruginosa and chironomid larvae existed together in water, the concentrations of chloramine DBPs all significantly increased, but the change trends were different. The concentrations of trichloromethane （TCM） and trichloroacetic acid （TCAA） gradually increased, and the concentrations of chloral hydrate （CH） and dichloropropanone （DCP） initially increased and then decreased with increasing total organic carbon （TOC） concentration. The concentrations of TCM, dichloroacetonitrile （DCAN）, CH, DCP, dichloroacetic acid （DCAA） and TCAA all increased with increasing chloramine dosage. The concentrations of CH and DCP firstly increased and then decreased, with a maximum value at 48 hours. The increase of pH was conducive to the formation of TCM and TCAA. The concentration of DCAN decreased with increasing temperature. The maximum values of CH and DCP were 1.43 μg/L and 1.22 μg/L at 20 ℃, respectively.