What is industrial wastewater and how is it classified?
Definition of industrial wastewater and classification of industrial wastewater based on the type of pollutant.
In the simple definition of what is industrial wastewater and how it is classified, it should be said that industrial wastewater is water that is used in the production and manufacture of a commercial product and is removed from the system as a by-product.
Industrial wastewater is a by-product of manufacturing plants. Various factories that can produce the food, clothing, beverages, paper and all kinds of chemicals we need. In all these products, water is used as a consumable part of the production process.
Due to the diversity of industrial factories and the high volume of industrial wastewater in the country, we need to identify appropriate methods for the management and treatment of industrial wastewater. The first step in managing industrial wastewater is to fully understand the effluent of factories.
One of the priorities of Watek is the specialized center for water acceleration, treatment and recirculation. In this article, we review and classify the types of industrial wastewater.
Types of contaminants and impurities in industrial wastewater
Impurities in industrial wastewater can be classified into two general groups: organic pollutants and inorganic pollutants.
Includes a variety of mineral salts, alkalis, chlorine, ammonia, mineral acids and….
Includes a variety of sugars, fats, oils, proteins, hydrocarbons, organic acids and….
Some organic pollutants are resistant to decomposition and their presence is toxic and dangerous to aquatic life. On the other hand, the presence of organic pollutants in water reduces the amount of dissolved oxygen in water. If the amount of dissolved oxygen in the water is less than the allowable minimum, that water is considered contaminated.
Due to this issue, eliminating or reducing the concentration of organic pollutants is of great importance for maintaining the health of the environment and organisms.
Industry classification based on wastewater production
The active industries in the country can be divided into three main categories in terms of wastewater production:
Industries without sewage: Industries whose production process is not dependent on water, therefore do not have sewage. Like home appliance factories
Medium Wastewater Industries: These are a group of industries that are part of the production process that depends on water. Like textile factories
Industries with high wastewater: Industries that all production processes depend on water and as a result produce a very high amount of industrial wastewater. Like food factories
Classification of industrial wastewater by industry
Paper and paper pulp
Paper production is one of the most consumed industries in terms of energy and water. Biochemical oxygen content (BOD) and chemical oxygen content (COD), solids and organic compounds are among the major pollutants in paper and pulp wastewater. The paper and pulp industries are among the industries that produce large amounts of wastewater.
Extraction of minerals and types of metallic and non-metallic minerals requires water consumption. Wastewater from mining plants includes mineral particles, metals, acids, salts and hydraulic oils.
Oil and Petrochemical
Petrochemicals are one of the major producers of industrial wastewater in the country. The major pollutants in petrochemical wastewater are organic. Biochemical oxygen content (BOD) and chemical oxygen content (COD), solids and organic compounds are among the main pollutants in petrochemicals and petroleum industries.
Iron and steel
The major pollutants in steel mills are biochemical oxygen content (BOD) and chemical oxygen content (COD), metals, oils and fats, acids, phenols and cyanides.
The food industry is one of the industries that produce a lot of wastewater. Major contaminants in the food industry are biodegradable and non-toxic. Biochemical oxygen content (BOD) and particulate matter (SS) are major contaminants in food industry wastewater.
Leather and textiles
The textile industry is one of the industries producing medium wastewater. Major contaminants in the textile industry wastewater are caused by pigments and various additives required for dyeing. Biochemical oxygen content (BOD) and particulate matter (SS), sulfate and chromium are the major contaminants in textile industry wastewater.
The use of complex structures in the chemical industry can lead to the production of wastewater containing chemical oxygen (COD), a variety of organic compounds, heavy metals, suspended solids (SS) and cyanide.