Wastewater

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Sewage is a waste product from various human activities that contains physical, chemical, and biological pollutants that can endanger the environment. Most of the wastewater is water, but there are other substances that vary depending on the type of wastewater, its concentration and amount of substances.
Wastewater treatment
The process of separating various pollutants from industrial and domestic effluents so that the treated water can be reused is called wastewater treatment. In this process, all kinds of industrial and domestic effluents are purified and disinfected, they can be reused and even turned into fresh water.
It can be said that in recent years, due to depletion of water resources, biological crises and successive droughts, sewage has been used more than ever. To do this, they must be treated through processes before being released into the environment. Therefore, water purification is important in two ways, firstly to provide water resources and secondly in order to prevent the entry of various pollutants into the environment. The water treatment process is done in different ways, which leads to the direct use of water in the cycle or is left in nature with the least risk. The amount of water consumption that ultimately leads to the generation of wastewater depends on several factors. They include things like climate, water prices and pressures, and water system management.
Different refinery units
Inlet Channel
Coarse Screen
Screw Pumps Screw Pumps
Fine Screens
Influent Partial Flumes
Grit Chambers
Primary Sedimentation Tanks
Aeration Tanks
Secondary Sedimentation Tanks
Chlorination Tanks
Effluent Partial Flume output current measurement unit
Primary Sludge Thickener Tanks
Anaerobic Digestion Tanks Anaerobic Digestion Tanks
Gaz Holder
Secondary Sludge Thickener Tanks
Sludge Drying Beds
Sludge Lagoons
Types of sewage
Wastewater is classified into three groups based on the source of production and their production characteristics.
Municipal or sanitary sewage
Municipal wastewater comes from different parts of homes such as kitchens, bathrooms, and sanitary facilities such as dishwashers and laundries, and is usually gray in color. Municipal wastewater is usually discharged into a sewer or septic tank or municipal sewage system, the gray color of which initially turns black and dark after a while. Pure and fresh municipal wastewater is usually neutral or alkaline. With the onset of decay, the acidity of the effluent decreases. The properties of this wastewater are almost the same in every country and only its concentration is variable.
Surface sewage
This wastewater, which is generally obtained from melting snow and rain, and due to flowing on the ground, carries a variety of materials with it. Most of the materials in this type of sewage are sand, which is added to the water when passing and washing the streets, and some organic and mineral materials are added to them. At the beginning of rainfall, the degree of surface water pollution is high and after cleaning the rainfall surfaces, the amount of pollution decreases. Surface sewage is usually considered clean and safe for water sources.
Industrial wastewater
The most variable type of wastewater between the above two is industrial wastewater. Because depending on the nature and type of activity of the factory and workshop, they will have different outputs. The corrosive properties and chemical and toxic compounds in this wastewater are much higher than other types of wastewater. Effluents from acidic and chemical materials in factories and industrial companies have become a major issue with the reduction of water resources and the increasing expansion of various industries. In this regard, we can name some industrial wastewaters that contain different materials. These include food industry wastewater, slaughterhouse wastewater (containing blood), and refinery wastewater (containing oil and fat). Various parameters such as the temperature of the effluent, the concentration of pollutants, the discharge of the effluent are also considered in determining the quality of industrial wastewater.
Purification steps
The first step in the wastewater treatment process is its collection. The transfer of effluents must be done in hygienic conditions so that the transfer pipes are free of leaks and corrosion and the people responsible for it also have special clothes. Sewage must be transported to a treatment plant through an underground drainage system. The treatment stages can be divided into primary treatment, secondary treatment and tertiary treatment (advanced treatment). Primary treatment, which is generally a physical treatment operation, and the units used at this stage usually include debris, grain, degreaser, and primary sediment.
Another important step is odor control, which is used with the help of chemicals to eliminate the unpleasant odor of sewage. Screening involves removing anything that has entered the sewage as an additive. These include a variety of consumables including plastics, bottles, cotton and similar items. At this stage, which is also known as activated sludge secondary treatment, particulate suspended solids and BOD5 are removed. In general, secondary treatment includes biological treatment and the most effective in the process of this stage of treatment, microorganisms b