The process of improving water quality to make it more acceptable for various purposes is called water treatment process. Many uses of healthy water after water treatment process includes household usage, irrigation, industrial water supply, medical, etc.
The treatment process for healthy usable water is done by removing of contaminants of raw water, minerals, algae, and other substance that might have adverse health effects if consumed. Wastewater reuse in all the different kinds of fields can be counted as a water-saving measure.
Types of wastewater:
Wastewater can be mainly divided into two major categories:
- Sewage wastewater: The wastewater from domestic uses, such as toilets, showers, and washing at kitchen and laundry falls under the category of sewage wastewater.
- Industrial wastewater: This category contains wastewater released from different kinds of industrial, manufacturing, commercial plants. The chemical compositions of this kind of wastewater also vary from that of sewage wastewater.
Municipal wastewater originates from municipalities. It is comprised of sewage wastewater, industrial wastewater, and rainwater that is flowing through the public sewer.
The process of wastewater treatment:
Wastewater treatment process converts wastewater- water that is no longer suitable for use- to be safe enough to discharge back into the environment. The process of wastewater treatment is long one, but it removes all the harmful metals, pathogens, nitrogen, and phosphates. A basic wastewater treatment system mainly includes:
- Collecting wastewater: Wastewater is drained to the wastewater treatment plant by gravity and is collected in one place to be treated.
- Clarifier or pretreatment: this process removes large and small solids from wastewater, which can also be described as settling of solid particles.
- Removal of grit: After removing large solids, the next step is to remove sand, stones and grits and gravels.
- Sedimentation: Above is the process of separation of wastewater from solids, grits, and gravels. During sedimentation, wastewater flows to what can be termed as ‘pre-settling basins.’ Settling basins are ponds designed for the purpose of removing suspended solids from water using gravity. Sedimentation can be defined as the act of depositing sediments. That was primary treatment. Secondary treatment, also known as biological treatment, includes the use of bacteria that contaminants such as biodegradable organics and dead bacteria, etc.
- Filtration: Filtering remove all remaining traces of suspended solids from the wastewater and makes it reusable by the various oxidation process. The oxidation process may include biochemical oxidation to remove organic compounds. Chemical oxidation to remove organic pollutants.
- Final pH adjustments: Following the above-mentioned treatments polishing is done to the water to adjust pH levels to reduce chemical reactivity that might occur as a result of chemical oxidation done in the filtration process.
The benefits of reusing water gone through the water treatment process are that it costs less than a few other sources; it is always available regardless of season, weather, changing climates. One of the major positive outcomes is that when treated water is used in irrigation, the nutrient used during the wastewater treatment process can act as fertilizers in the agricultural fields. The increase in water availability is another positive outcome.