Abstract:

A new method of treating wastewater from the 4,4′-diaminostilbene-2,2′-disulfonic acid (DSD) industries is proposed.The wastewater is oxidized by Fenton reagent at 70-80 ℃.The range of the inital pH of the water sample is 1-4,the volume ratio of H₂O₂ to wastewater is 1×10^-3 and it is put into the wastewater by three times with the reaction time of 30 min.Then the wastewater is flocculated and filtrated twice by using Ca(OH)₂ and FeSO₄·7H₂O as coagulation agents.It should be noted that the first flocculation is performed with the use of filter cake from the former batch.FeSO4·7H2O with the equivalent concentration of 6.25 g/L is used in the second flocculation.The total amount of Ca(OH)₂ used in one batch is 7.5 g/L.Industrial scale experiment has also been carried out and satisfied result has been yielded.

Key words: 4, 4 - diaminostilbene - 2, 2′- disulfonic acid, wastewater treatment, Fenton reagent, oxidation, flocculation

摘要：

采用Fenton试剂氧化、Ca(OH)₂和FeSO₄.7H₂O絮凝的办法处理DSD酸生产中的还原废水。通过实验找到了优化的废水处理条件:水样初始pH值为1～4,温度在70～80℃左右,30%的H₂O₂用量为1.0 mL/L,分三批投加到待处理废水中。氧化反应进行30 min。氧化后絮凝两次,第一次絮凝使用上批第二次絮凝的滤饼,第二次絮凝加入FeSO₄.7H₂O 6.25 g/L,两次絮凝共用石灰7.5 g/L。同时,根据实验室实验的结果进行了工业规模的实验。实验室和工业实验的结果表明,在此条件下废水处理效果良好,COD和色度均达到排放标准;处理成本低,适合工业应用。

关键词: DSD酸, 废水处理, Fenton试剂, 氧化, 絮凝

CLC Number: 

• TQ085

• X703