Three Stages of Wastewater Treatment

Priyanka Khaire

October 19, 2020

Wastewater

What Are the Three Stages of Wastewater Treatment?

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Secondary treatment of wastewater uses the biological process to reduce and remove biodegradable organic matter and contaminants and further act on the suspended solids that escape from the primary treatment.

To achieve this objective, wastewater plants provide a suitable environment for the naturally occurring living microbes to thrive and act aggressively on the organic matter.

The microbes feed on organic impurities for their growth and release by-products such as carbon dioxide, water, and energy.

The biological process is the most important part of wastewater treatment as the wastewater effluent is treated to achieve the quality that should match the standards set by the environment agencies.

Once that level of purity is achieved, the effluent is released into the disposal field.

Otherwise, polluted wastewater can cause great harm to human health and the environment.

Microbes perform under different sets of conditions. Secondary biological wastewater treatment can be aerobic and anaerobic based on different microbial communities used for treatment.

In certain conditions, both aerobic and anaerobic are coupled together as well.

Aerobic

In the aerobic biological process, microbes act on organic waste and suspended solids in the presence of a sufficient amount of oxygen.

The process converts waste and releases carbon dioxide, water, and other by-products.

Factors like temperature, pH, and oxygen available are important parameters that help microbes in the degradation of waste.

Anaerobic

The anaerobic process uses microbes in the absence of oxygen and successfully converts contaminants and waste into carbon dioxide, methane, and other end-products.

Biogas production is possible through the anaerobic process, which can be further utilized for running sewage treatment plants and systems.

Anaerobic systems should be completely closed and provided heat as they consist of different processes like hydrolysis, acidogenesis, acetogenesis, and methanogenesis, where microbes act as substrates.

There are 3 biological wastewater treatment methods that are currently in use, and microbes play the most important role in the success of each of the processes.

Activated Sludge

Microbes under oxygenated conditions form biological solids called activated sludge in the activated sludge process.

The microbes absorb dissolved organic matter in the wastewater and reduce the BOD. Oxygen is well supplied through the aeration system.

Clean water is skimmed and released as effluent, and the sludge is pumped out. A certain amount, usually 30% sludge, is reintroduced into the aeration tank as microbes are ready to metabolize organic waste more easily.

Tricking Filter

This biological treatment system consists of a bed of stones, rocks, gravel, etc. Wastewater is sprayed on the stones continuously which trickles down to the bottom.

As it reaches the bottom, microbes come together and multiply on the stones. Thus, microbes absorb contaminants, form a biomass layer, and lower BOD.

Air is made available during this process, too.

Oxidation Pond

Oxidation ponds, also called aerobic lagoons, are large and shallow earth basins where wastewater is treated by microbes, algae, and sunlight.

Here, algae release oxygen during the photosynthesis process, which is used by microbes.

As you can see in all the biological treatment of wastewater is possible only through powerful microbes.

However, due to the rapidly increasing population, industrialization, and other commercial activities, the amount of wastewater generated has increased exponentially.

The excess load of wastewater entering treatment systems has stressed the normal processes.

The performance of naturally occurring microbes is also affected significantly.

The lack of efficient microbes has led to low-quality effluent being released into the environment, which is harming the environment and humans on a large scale.

There is an urgent need to switch to innovative solutions that can maximize the productivity of secondary treatment of wastewater and biological processes.

Since setting up new plants in rural and urban areas costs too much, the solution that can improve the treatment processes is the need of the hour.

Organica Biotech’s Cleanmaxx is one of the best wastewater treatment products, which contains adaptable microbes that degrade organic waste aggressively, maximize BOD reduction, and minimize sludge formation.

The natural and eco-friendly formulation can power the biological process involved in secondary wastewater treatment.

This will ease the burden of sewage treatment plants and various treatment systems and methods, too.