All waters which have been used for some purpose, whether it’s domestic, industrial, or agricultural water, should be treated accordingly and returned to the natural draining or sewers without detriment to the environment and without disrupting the natural roundabout.
Untreated wastewaters have high temperature in average, and thus can be a source for various types of environmental pollution, for example, chemical emissions, aerosol particles, microorganisms and odors.
Waste waters can be divided into:
- Sanitary sewage,
- Industrial waters,
- Agricultural waters,
- Atmospheric waters,
- Infiltrated waste waters.
Sanitary sewage waste water is generated in the toilets of residential, public and other buildings where people live and work, in the physiological process of producing pollution in liquid and solid form. Here we also count the waste water from cleaning rooms, preparing food, washing dishes and clothes, personal hygiene.
Industrial waste water is generated in factories and plants after using water in the production process, and while washing machines, devices, etc. Today there is a large number of different industrial wastewaters, which are divided into a number of subtypes depending on the production technology.
Water pollution due to agricultural activities occurs when rain and melted snow flow over terrains whose state has already been violated by uncontrolled treatment and they wash out and take away chemicals and nutrients into the nearest lakes, rivers, wetlands, coastal waters or get washed by groundwater.
Atmospheric waste water – this water is formed as a surface runoff from rainfall and snowmelt from the urban areas. Wastewater from cleaning of street surfaces, sidewalks and more is also included in this waste water type.
Waste water treatment consists of procedures by which pollution reduction is accomplished to those quantities or concentrations to which treated wastewater discharged into natural water systems do not represent undesired changes to the environment. Therefore, the treatment of wastewater includes a series of operations and procedures to remove suspended and dissolved substances from water, or any substances that change properties of water.
Infiltrated waste water – is the ground water that touches the sewage network over pipe joints, drainage systems, etc. By its quality this is the cleanest, however, when in large quantities and dilutes sanitary sewage, it can disrupt the biological treatment in the plants.