摘要
根据净化含砷废水的铁盐中和法．通过理论分析和实验表明，在Ｆｅ／Ａｓ＝０．５—６．０范围内，铁盐中和法对废水中３价砷的去除率较其对５价砷的去除率平均低约６０％，证实了废水中的３价砷较５价砷难于去除。氧化剂选择研究表明，对于含砷量高的酸性废水，采用漂白粉［Ｃａ（Ｃ１０）２］氧化其中的３价砷最为适宜。对于含砷７８２．５ｍｇ／Ｌ，ｐＨ＝１的酸性废水，采用氧化－铁盐中和法经一级处理后，废水中含砷量即可低于８ｍｇ／Ｌ．除砷率大于９９％，二级处理后出水中砷含量即可低于国家排放标准（０．５ｍｇ／Ｌ）。
ased on the process of iron salts neutralization toremove arsenic from wastewater,theoretical analysisand experiments indicated that, at a ratio of Fe/As =0. 5-0.6, As(Ⅲ) was removed at a rate ofabout 60% lower than that of As (V),demonstrating that As(Ⅲ)was more difficult to beremoved from wastewater than As(V).In a furtherstudy,it was found that it was most suitable tooxidize As (Ⅲ)in acidic wastewater containing ahigh level of arsenic by using a bleaching powder,Ca(ClO)2.For an acidic wastewater containing 782. 5mg/L of As at pH=1, the oxidation/iron saltsneutralization process used in a primary treatmentproduced an effluent containing less than 8 mg/L ofAs, with an arsenic removal of more than 99%.Iffollowed by a further secondary treatment,the levelof arsenic in the effluent produced would be lowerthan 0. 5 mg/L,i.e.,the national standard for its discharge.
出处
《环境科学》
CAS
CSSCI
CSCD
北大核心
1994年第4期44-46,65,共4页
Environmental Science
关键词
酸性废水
净化
砷
废水处理
acidic wastewater, pollution control,arsenic (As),iron salts neutralization.
