工业污水处理程度划分
工业污水处理程度划分
Classification of industrial sewage treatment
现代污水处理技术,按处理程度划分,可分为一级、二级和三级处理。
Modern sewage treatment technology can be divided into one, two and three levels according to the degree of treatment.
一级处理,
First order treatment,
主要去除污水中呈悬浮状态的固体污染物质,物理处理法大部分只能完成一级处理的要求。经过一级处理的污水,BOD一般可去除30%左右,达不到排放标准。一级处理属于二级处理的预处理。
It mainly removes suspended solid pollutants in sewage, and most of the physical treatment methods can only meet the requirements of primary treatment. After one level of treatment, BOD can generally be removed by 30% or less. The first level treatment is a preprocessing that belongs to the two level treatment.
二级处理,
Two stage treatment,
主要去除污水中呈胶体和溶解状态的有机污染物质(BOD,COD物质),去除率可达90%以上,使有机污染物达到排放标准。
The removal rate of organic pollutants (BOD, COD), which is colloid and dissolved in sewage, is more than 90%, and the organic pollutants can be reached to the discharge standard.
三级处理,
Three stage treatment,
进一步处理难降解的有机物、氮和磷等能够导致水体富营养化的可溶性无机物等。主要方法有生物脱氮除磷法,混凝沉淀法,砂率法,活性炭吸附法,离子交换法和电渗分析法等
Further treatment of refractory inorganic substances such as organic matter, nitrogen and phosphorus can lead to eutrophication of water bodies. The main methods are biological nitrogen and phosphorus removal, coagulation sedimentation method, sand rate method, activated carbon adsorption method, ion exchange method and electroosmosis analysis method.