久久精品中文字幕一区-亚洲调教欧美在线-国色天香社区在线视频观看-无码人妻丰满熟妇区10p-国产男人天堂-农村黄色片-亚洲草逼视频-国产冒白浆-九色porny丨自拍视频-欧美性少妇xxxx极品高清hd-精品国产99久久久久久-久久久久久美女-九色婷婷-51久久国产露脸精品国产-久久综合综合久久高清免费

Solution for heavy metal wastewater

Heavy metal wastewater generally comes from industries such as mining, metal smelting and processing, electroplating, leather making, pesticides, papermaking, painting, printing and dyeing, nuclear technology, and petrochemicals. Heavy metals are difficult to biodegrade and are easily absorbed and enriched by organisms. Their toxicity is persistent and they are a highly potential hazardous pollutant. The treatment processes for heavy metal wastewater include chemical precipitation, physical adsorption, ion exchange, and phytoremediation. For heavy metal wastewater with high recycling value or concentration, chemical precipitation or membrane method can be used to concentrate and recover the heavy metals.