- Domestic wastewater results from water use in residences, businesses, and restaurants.
- Industrial wastewater comes from discharges by manufacturing and chemical industries.
- Rainwater in urban and agricultural areas picks up debris, grit, nutrients, and various chemicals, thus contaminating surface runoff water.
How is wastewater formed?
Domestic Wastewater : is wastewater formed by a number of activities such as bathing, washing, using the toilet, and rainwater runoff. Wastewater is essentially used water from water use in residences, businesses, and restaurants.
Domestic wastewater, is relatively easy to treat.
Some wastewaters are more difficult to treat than others. For instance, industrial wastewater can be difficult to treat due to its high strength that discharges by manufacturing and chemical industries.
There are a number of ways in which wastewater can cause pollution problems, considering not all waste makes it to wastewater treatment plants.
Preliminary and primary stages remove rags and suspended solids.
Secondary processes mainly remove suspended and dissolved organics.
Tertiary methods achieve nutrient removal and further polishing of wastewater.
Disinfection, the final step, destroys remaining pathogens. T
he waste sludge generated during treatment is separately stabilized, dewatered, and sent to landfills or used in land applications.