What are the five stages of a Sewage treatment plant?

When sewage was discharged into streams years ago, a natural cleansing process began. The sheer volume of clean water in the stream diluted trash in the first place. Bacteria and other small organisms in the water ate the sewage and other organic materials, producing new bacterial cells, carbon dioxide, and other products.

With today's growing population and increased amount of domestic and industrial wastewater, towns must lend a hand to nature. The primary goal of wastewater treatment is to speed up the natural purification processes.

The treatment of wastes has five fundamental steps, which are explained here:

1. Move about

The first stage is to ensure that wastewater reaches the sewage treatment plants. It has to take the same path regardless of where it originates from. The sewage is routed down drains and into sewers, where it is subsequently sent to the nearest sewage treatment plant via underground pipelines.

2. Preliminary screening

A lot of things that shouldn't be there end up in the sewer system. Nappies, sanitary pads, incontinence pads, condoms, cleaning and make-up wipes, plastic bags, and other items, for example, must all be removed before sewage treatment can begin. At this point, any debris or gravel that has washed in from the roads is removed.

3. Primary settlement

Separating any suspended solids is the next step in the sewage treatment process. Pumping the wastewater into enormous sedimentation tanks does this. Solid waste particles are heavy, so they sink to the bottom of the tank. They build a sludge layer here, which can then be removed.

4. Sewage treatment in the secondary stage

Now that all visible trash has been removed, it's time to focus on the dirt that can't be seen.A two-stage biological treatment is used to accomplish this. To begin, wastewater is collected in big tanks with air piped in to promote bacterial growth. The 'activated sludge process' is what it's termed. The water is then routed through specialized filter beds. Billions of 'waste-eating' bacteria live in these beds, digesting organic stuff and breaking it down into harmless molecules.

5. Treatment at the tertiary level

The wastewater treatment process draws to a close with this stage. The water is already exceedingly clean at this point; all that's left to do is remove the final few waste particles before it can be discharged. The type of tertiary sewage treatment required will be determined by the receiving water's nature and sensitivity. Disinfection is generally required for bathing or shellfish waters, for instance.

Phosphorus and nitrates (nutrients found in sewage) will also need to be removed to protect eutrophicated waters (i.e., excessive richness of nutrients).The procedure is the same in either case. Before being released into the chosen water body, the wastewater is simply routed through a special tank called a humus tank or a reed bed.

Please contact Netsol Water, if you have any questions about the water treatment process or would want any assistance on how to optimize wastewater management!