悬浮结晶法预处理敌草胺生产废水

采用悬浮结晶法对敌草胺生产废水进行焚烧前预处理,研究了不同成冰率条件下废水的处理效果,并对冷冻过程中的析出晶体进行了表征。在成冰率为61.3%时,出水COD、色度和电导率的去除率分别可达94.0%、99.2%和89.1%。出水pH为9～10,满足后续生化处理的pH要求。在成冰率为61.3%时,一级浓缩液热值较原水增加了129%,且焚烧量大幅下降。析出晶体的主要组分为KCl和脂肪族酰胺。在成冰率为61.3%时,每处理1 t原水可回收89 kg析出晶体,具有较好的资源化利用前景。

Pretreatment of napropamide production wastewater by suspension crystallization method

The napropamide production wastewater was pretreated before combustion by suspension crystallization method. The treatment effects of the wastewater under different ice formation rates were studied,and the precipitated crystals in the freezing process were characterized. When the ice formation rate was 61.3%,the removal rates of COD,chroma and conductivity of the effluent were 94.0%,99.2% and 89.1%,respectively. The effluent pH was 9-10,which met the pH requirement of follow-up biochemical treatment. When the ice formation rate was 61.3%,the heat value of the first-grade concentrate increased by 129% compared with the initial wastewater,and the combustion amount decreased substantially. The main components of the precipitated crystals were KCl and aliphatic amides. When the ice formation rate was 61.3%,89 kg precipitated crystals was recovered from 1 ton initial wastewater,with a good prospect for resource utilization.