Arsenic removal from wastewater treatment have?

Arsenic waste water processing, has been popular since the 1960 s. At present, the arsenic wastewater treatment methods mainly include chemical precipitation method, chemical method and biological method.

chemical method is usually ion exchange, adsorption, extraction, and reverse osmosis method.

microbial method with activated sludge method, bacteria and algae symbionts method and active sludge method, etc. In general, microbial method is efficient, economic and no secondary pollution, etc, therefore, has become recognized as the most promising approach.

chemical precipitation can be subdivided into two kinds: one kind is to arsenic precipitation for an intermediate product, and then converted into arsenic product sale, this method can avoid sediment arsenic in the process of long-term storage may produce secondary pollution; Another kind is the deposit for the stable compounds after arsenic precipitation, this method is the disposal of industrial wastewater of high concentration of arsenic using one of the most common method.

until the 1990 s, most of the simple lime milk neutralization precipitation arsenic wastewater treatment, but the income of the arsenic deposits ( Including arsenic acid calcium, etc. ) The dissolved in the tailings pool, to make every litres of tailing pond arsenic concentration in the waste water up to a few grams, so it has less used. Ideal arsenic removal method, technically, not only must ensure that the processing after external drainage meet environmental protection requirements, and the sediment arsenic has high stability, suitable for long-term storage.

arsenic arsenic toxicity harm and industry distribution are generally toxic, toxicity related to their chemical properties and valence. Trivalent arsenic toxicity is about 60 times higher than pentavalent arsenic, pentavalent arsenic in the body will be restored into trivalent arsenic. In addition, the arsenic in the human body contains significant savings, human dose low arsenic, after 1 ~ 2 years, or even more than ten years or decades later, possible arsenic poisoning symptoms. Therefore, industrial waste water must be strictly deal with arsenic.

mining, non-ferrous metal smelting, sulfuric acid preparation, chemical, dyes and pesticides production industrial fields such as the wastewater often contains arsenic, its high concentration of up to hundreds of milligrams per liter, even thousands of milligrams, individual arsenic refractory gold ore leaching liquid of arsenic concentration up to 20 ~ 56. 5g/L。 A lot of waste water, mainly exists in the form of trivalent arsenic, and there are mainly five price form.