Wastewater treatment is a series of measures aimed at extracting foreign impurities from water before being dropped into water bodies. It is produced using various means and methods. Sewage may contain particles of both soluble and insoluble impurities. Particles of impurities are classified by size:
Emulsions and suspensions – the particle size is 0.1 ?m.
Colloids – particle size in the range 0.1 ?m – 1 nm.
Dissolved particles, the size of which corresponds to the size of the molecules.
Classification of wastewater treatment methods:
The simplest mechanical methods of wastewater treatment, in other words, filtration and hydrodynamic processes. Hydrodynamic includes gravitational, as well as centrifugal settling.
Physicochemical methods of wastewater treatment, including chemical treatment of effluents, as well as thermal ones.
Biochemical methods of wastewater treatment.
Industrial wastewater treatment tanks
The selection of the cleaning process is carried out depending on the degree of contamination, the content of impurities and the size of the particles of contaminants.
In nature, self-cleaning of soil and water occurs due to biological methods of purification. Impurities in contaminated water are processed by microorganisms that live naturally in soil and water. Under the action of microorganisms, organic inclusions decompose to form water, gas and other simple compounds.
Natural methods are quite effective, but proceed very slowly. To speed up the process, an environment ideal for their life is created for microorganisms and other methods of intensifying the purification process are used.
There are aerobic and anaerobic bio-cleaning methods. In the first case, microorganisms need oxygen for sewage treatment, so it is necessary to ensure the supply of air to the environment to be cleaned. Air can be supplied naturally (that is, by building ventilation) or forced (by means of a compressor).
Mechanical methods are used in almost all treatment plants. Their essence lies in the removal of mechanical impurities by filtration and sedimentation. To remove coarsely dispersed particles, use screens, gratings, sand catchers and other coarse filtration plants. In addition, in installations, the settling method is widely used, that is, the separation of effluents into fractions by specific gravity.