Industrial wastewater of food factories
Industrial wastewater of food factories and plants are considered to be highly concentrated in terms of organic pollutant content. Therefore, their purification is divided into several stages: mechanical – using percolator grids. Collection of the main fat mass using special traps. Removal of colloidal impurities and emulsified fats using flotation plants or anaerobic bioreactors. Sludge treatment and floating slurry collection. Also, lightening of sewage and reactant treatment nodes using coagulants and flocculants is used. It all depends on the company’s specialization, because technological solutions for meat, milk and fish processing factories have their own specifics and are directly connected with the production process. Thus, meat processing plants use the method of reagent pressure flotation, which enables capturing of the main fat mass using traps. At companies engaged in production of oil and fat products, such as soap, margarine, glycerine, vegetable oils, etc., wastewater is polluted by emulsified fats. Their content is 150 to 1200 mg/l. Then pressure flotation requires the use of coagulants with separation of coagulated pollutants. After that, sewage can be used again or subjected to post-treatment.