How to treat industrial wastewater? With regard to the characteristics of industrial wastewater treatment, we believe that appropriate pretreatment methods should be adopted according to the actual wastewater quality, such as flocculation, internal electrolysis, electrolysis, adsorption, photocatalytic oxidation and other skills, so as to damage the refractory organics in the wastewater and improve the biodegradability of the wastewater; The industrial wastewater is further treated by biochemical methods, such as SBR, contact oxygen industrial technology, A/O skills, etc.
Industrial wastewater, including produced wastewater and produced sewage, refers to wastewater, sewage and waste liquid occurring in the process of industrial production, which is rich in industrial production materials, central products and products lost with water, and pollutants occurring in the process of production. With the rapid development of industry, the variety and quantity of waste water have increased rapidly, and the pollution of water body has become increasingly widespread and severe, threatening human health and safety. Therefore, in terms of environmental protection, the treatment of industrial wastewater is more important than that of urban sewage.
1、 Classification of industrial wastewater
Industrial wastewater generally includes the following three types:
1. According to the chemical properties of the primary pollutants contained in industrial wastewater, inorganic wastewater mainly contains inorganic pollutants, and organic wastewater mainly contains organic pollutants. For example, electroplating wastewater and mineral processing wastewater are inorganic wastewater, food or oil processing wastewater is organic wastewater, printing and dyeing professional production process is mixed wastewater, and different professional cleaning wastewater contains different components.
2. Classified according to the products and processing policies of industrial enterprises, such as metallurgical wastewater, papermaking wastewater, coking gas wastewater, metal pickling wastewater, chemical fertilizer wastewater, textile printing and dyeing wastewater, dye wastewater, tanning wastewater, pesticide wastewater, power plant wastewater, etc. The third is classified according to the primary components of pollutants contained in wastewater, such as acid wastewater, alkaline wastewater, cyanide wastewater, chromium wastewater, cadmium wastewater, mercury wastewater, phenol wastewater, aldehyde wastewater, oil wastewater, sulfur wastewater, organic phosphorus wastewater and radioactive wastewater. The first two classifications do not touch the primary components of pollutants contained in wastewater, nor can they indicate the harmfulness of wastewater.
3. According to the primary components of pollutants contained in wastewater, it can be divided into acid wastewater, alkaline wastewater, phenol wastewater, chromium wastewater, organic phosphorus wastewater and radioactive wastewater.
2、 Primary pollutant of industrial wastewater
The pollution of industrial wastewater mainly includes: organic aerobic matter pollution, chemical poison pollution, inorganic solid suspended matter pollution, heavy metal pollution, acid pollution, alkali pollution, plant nutrients pollution, heat pollution, pathogen pollution, etc. Many pollutants have color, odor or foam, so industrial wastewater often presents an unpleasant appearance, resulting in large-scale water pollution, which directly threatens the lives and health of the people. Therefore, it is particularly important to control industrial wastewater.
The purpose of industrial wastewater treatment is to separate the pollutants in the wastewater in some way, perhaps transform them into harmless and stable substances, so as to purify the wastewater. Generally, avoid the infection of poisons and germs; Avoid visible objects with strange smell and bad feeling to meet the needs of different uses.
3、 Treatment methods of industrial wastewater
It is necessary to consider the method of treating industrial wastewater according to the quality and quantity of wastewater, the receiving water body discharged or the use of water. The treatment and utilization of sludge and residue in the process of wastewater treatment, the possible secondary pollution problem, and the recovery and utilization of flocculants should also be considered.
In wastewater treatment projects, traditional biochemical skills, such as A/O method, A2/O method, or improved skills, are mostly used. The activated sludge process is a commonly used biological treatment method for organic wastewater. Activated sludge is a high power artificial biological treatment method with large specific surface area, high activity and good mass transfer.
