BARF对饮水中微量百菌清与毒死蜱的去除特性

以模拟饮水处理工艺沉淀池出水为试验原水，采用连续流试验装置研究BARF对百菌清与毒死蜱的去除效果，并分析了BARF对两种物质的去除机理。水温为24～27℃条件下的试验结果表明，当空床停留时间（EBCT）在7.5～30 min，BARF对百菌清与毒死蜱去除率分别达到66.7%～86.2%、69.6%～93.0%，两种物质去除率随EBCT增加而增加，但超过15 min后增幅较小；当EBCT为15 min，在15～20℃、10～15℃、<5℃ 3个温度段内，BARF对百菌清的平均去除率分别为84.2%、79.3%、59.8%，对毒死蜱的平均去除率分别为92.7%、91.4%、80.3%，温度降低不利于两种物质去除。试验水质下，EBCT为15 min、水温高于15℃时，BARF出水百菌清与毒死蜱浓度可达到国家现行饮水水质标准；BARF启动之初对百菌清与毒死蜱的高效去除主要靠活性炭吸附作用，生物膜稳定后，生物作用对两种物质的去除具有较大贡献。

Chlorothalonil and chlorpyrifos removal from drinking water by BARF

Chlorothalnial and chlorpyrifos are widely used in China, so they are likely to be present in source water, but the traditional drinking water treatment process cannot removal them well. In view of the polluted water sources, there has been a number of new drinking water treatment technologies, and among them bioactive rapid filter (BARF) has the vast application prospect in China. There are few reports about chlorothalonil and chlorpyrifos removal from drinking water by BARF, so the effect and mechanism of chlorothalnial and chlorpyrifos removal by BARF were studied in this paper with a pilot test device of BARF, and raw water was simulated effluent of settling tank of traditional drinking water treatment process, empty bed contact time (EBCT) is a key design parameter for BARF. The experiments for the influence of EBCT were conducted in the temperature range of 24℃ to 27℃, and the results showed that BARF could remove chlorothalonil and chlorpyrifos significantly when EBCT was in the range of 7.5 min to 30 min. Chlorothalonil removal rate ranged from 66.7% to 86.2%, chlorpyrifos removal rate ranged from 69.6% to 93.0%. Increasing EBCT tended to increase removal rates of the two substances, but the increase was not obvious beyond 15min. Water temperature may have seasonal change, so chlorothalonil and chlorpyrifos removal by BARF was investigated in three temperature ranges (15—20℃, 10—15℃, <5℃) when EBCT was 15 min. Removal rates of chlorothalonil were 84.2%, 79.3%, 59.8%, and removal rates of chlorpyrifos were 92.7%, 91.4%, 80.3% respectively. It was shown that a low temperature seemed to be unfavorable for the removal of the two substances and water temperature affect chlorothalonil removal more intensely. In general, BARF could remove chlorothalonil and chlorpyrifos effectively. For test water quality, when temperature of raw water was above 15℃ and EBCT was 15 min, the concentrations of chlorothalnial and chlorpyrifos of effluent could meet the current water quality standard for drinking water of China. Adsorption tests showed that activated carbon used in this study could adsorb chlorothalonil and chlorpyrifos well, contributing to high removal rates of the two substances at the start of BARF pilot test. When biofilm was stabilized, biological function played a greater role in chlorothalonil and chlorpyrifos removal.