碱减量—印染混合污水的处理

Treatment of Mixed Waste Water from Alkali Decrement_Printing and Dyeing

采用在生化处理前进行酸化 -混凝预处理 ,或在生化处理后进行后处理(混凝沉淀或铁碳曝气)的方法处理印染 -碱减量混合污水 ,保证处理出水满足GB4287 -92二级排放标准。通过先加酸酸化去除污水中的TA,然后再进行生化处理 ,不但CODcr总去除率可达93 %以上 。

The waste water from alkali decrement_printing and dyeing is featured by complicated composition and high CODcr content,and is difficult to degradate bio_chemically.With the treatment using only biological oxidation the removal rate of CODcr may only reach 65%～80%.This paper put forward some suggestions and proved through experiments that either the pre_treatment of acidification_coagulation before biochemical treatment or the post_treatment (coagulation,sedimentation or iron/carbon aeration)after biochemical treatment may ensure that the outlet water will meet the grade_two discharge standard in GB 4287-92 in the treatment of the waste water from alkali decrement_printing and dyeing.The addition of acid for acidification to remove TA in the waste water followed by biochemical treatment makes it possible that the total CODcr removal rate will reach 93% or higher and the time for the treatment will be significantly shortened.