In water treatment industry, ferrous sulfate is mainly used as flocculant with good flocculation effect; It has good decolorization ability; It also has the functions of removing heavy metal ions, oil, phosphorus and sterilization. Especially, ferrous sulfate has obvious effect on decolorization and COD removal of printing and dyeing wastewater, ferrite coprecipitation of electroplating wastewater, etc., and ferrous sulfate is cheap, so it is worthy of the first choice for printing and dyeing, electroplating and other wastewater treatment. When the quality of the make-up water is poor or the concentration ratio of the circulating water is high, the traditional water treatment method is to add both medicine and acid to regulate the pH value and alkalinity of the circulating water and reduce the scaling probability. No matter how poor the water quality is, no matter how high the ratio is, the circulating water system does not add acid, but has a good treatment effect.
Ferrous sulfate precipitant: it can form precipitates with sulfides and phosphates to remove sulfides and phosphates. Example: ferrous sulfate is used to treat sulfur-containing wastewater from printing and dyeing plants.
Ferrous sulfate original agent: ferrous sulfate is a strong reducing agent, which can reduce hexavalent chromium from chromium wastewater containing water to trivalent chromium, instead of expensive sodium sulfite, sodium bisulfite, sulfur dioxide, etc. The utility model has the advantages of no toxic carcinogenic stimulating chlorine body (mainly sulfur dihydrogen) and low price.
Used as Fenton reagent. Fenton process is a kind of wastewater treatment system, which uses ferrous sulfate as catalyst and hydrogen peroxide (also known as hydrogen peroxide) for oxidation reaction. Fenton reagent can react to produce hydroxyl radicals with strong oxidation, which can be destroyed and decomposed with the structure of insoluble organic pollutants in wastewater, so as to achieve the purpose of pollutant removal.
When ferrous sulfate is used, it is usually prepared into 10% - 25% aqueous solution and fully dissolved. Then it is put in front of the primary sedimentation tank in the wastewater treatment process.
Ferrous sulfate is used for sewage treatment. What method should be used to add and is it convenient to reduce labor intensity? Depending on the nature and treatment capacity of sewage, there are different treatment processes and different dosage methods. Based on the experience of water treatment, let's share the following relevant cases. In the 50000 / T municipal wastewater treatment plant, the treatment process is cast, ferrous sulfate dosing is continuously distributed by two dissolving tanks, and the metering pump is added with ferric oxide in the backwater treatment. 30000 / T printing and dyeing wastewater treatment plant.