For most industrial companies, water purification is a part of their production process. Industries use wastewater treatment plant to treat wastewater and remove pollutants.
Wastewater treatment plants ensure that the safety precautions and discharge regulations are fulfilled. A functional industrial water treatment system helps to avoid harm to the environment, human health, and ensures the facility’s process and products are up to the mark.
Industries should consider wastewater management as the improper discharge of wastewater can result in paying heavy fines and possible legal action.
In this article, we will cover everything about the function, process, and stages of wastewater treatment plant.
What are the 3 stages of wastewater treatment plant?
There are three main stages of the wastewater treatment plant process.
1. Sedimentation Stage
The sedimentation stage, also known as primary treatment, involves parting heavier solid and lighter solid from wastewater. Wastewater is held in a settling tank where heavier solid waste sinks to the bottom, and lighter solid waste floats above the surface.
Upon settling, these materials are repressed while the remaining liquid is moved through to the secondary stage of water treatment.
2. Biological Stage
The biological stage, also known as secondary treatment, is where the biological content of the waste is substantially degraded through aerobic biological processes. The secondary treatments ensure the safe release of wastewater into the local environment.
3. Water Quality Check
The inspection stage is designed to raise the water quality to domestic and industrial standards or to meet specific requirements around safe water discharge. The tertiary treatment stage includes the removal of pathogens from water and ensures that water is safe for drinking purposes.
What Is the Process of Wastewater Treatment?
1. Preliminary Treatment
Wastewater is drained to the treatment plant by gravity through the main sewer systems. The water is transferred to the gravel chamber to settle out the grit from the water.
Upon settling, gravel is disposed of at the dump, while the remaining liquid is moved through the screening process. Bar screens help discard large objects from the water, while coarse screens and fine screens are used to remove smaller objects such as matches or cigarette butts.
After the removal of large objects, the water is moved through the grit chamber to discard grit. Grit chamber functions similar to gravel chamber – allowing the settlement of grit, removing the remaining grit, and disposing of it.
2. Primary Treatment
Primary water treatment, also known as the sedimentation stage, is where the grit-free water is transferred to primary settling tanks for further purification. The wastewater is driven towards a large cone-shaped tube known as a hopper.
These hopper tubes have arms that move around the edge of the tank with an approx velocity of 4 cm/s to treat wastewater. The purpose of using a hopper is to separate treated water and sediments. Upon the completion of primary treatment, secondary wastewater treatment starts.
3. Secondary Treatment
The secondary treatment, also called the biological stage, uses natural processes to further treat wastewater. During secondary treatment, wastewater treatment plant use bacteria to consume the contaminants, especially biodegradable organics, carbon, and phosphorus.
Dead bacteria and organic residues transform into sludge, which is then pumped out and moved to digestion tanks before the settling tanks.
The sludge is transferred to digestion tanks where it is heated and mixed. The heated and mixed sludge is converted into biogas, which wastewater treatment plant can use for a variety of purposes – electrical and thermal energy production.
After the completion of the sludge digestion process, the second digestion stage takes place in storage tanks. The second digestion stage involves separating water from semi-solid sludge, which is transported back for further wastewater treatment. The remaining semi-solid sludge goes through mechanical dewatering.
Upon going through all the processes, the sludge is finally disposed of at the dump. Within a month or so, the disposed of sludge is dried out and ripe enough to be used for the fertilisation of industrial crops.
After separating sludge from the wastewater, a final inspection of service water takes place. The purpose of performing a final inspection is to check the contamination level and ensure that the treated water complies with the necessary standards.
The final inspection also defies whether the treated water can be released to be reused for domestic and industrial purposes.
Why Are Wastewater Treatment Plant Required?
Wastewater treatment plant help dispose of human and industrial waste without causing any damage or danger to both the human and natural environment.
What are The Advantages of Wastewater Treatment Plants?
- Gets rid of potential diseases
- Minimal odour emissions
- Require low maintenance
- Break down solids faster
How Do We Treat Wastewater?
There are four common ways to treat wastewater.
- Physical water treatment
- Biological water treatment
- Chemical treatment
- Sludge treatment
We design, manufacture, and install a wide variety of innovative water and wastewater products and services. If you are interested in wastewater treatment, call us on 1300 557 009 today.