Understanding Different Wastewater Treatment Plants

wastewater treatment plants

With the alarming rate at which groundwater is disappearing, water is becoming a critical component. Clean water has become more critical than ever in today’s world. We know water covers 70% of our planet, and we always think it is plentiful. However, freshwater, i.e. the water we drink, bathe in and irrigate our farm fields with, is incredibly rare. Only 3% of the world’s water is freshwater, two-thirds of which are frozen glaciers or unavailable for our use. Around 1.1 billion people worldwide lack access to water, and a total of 2.7 billion find water scarce for at least one month of the year.

How do we solve this crisis? Is there any way to reuse the generated wastewater so that we don’t fall short of water? Well, the answer to this is yes! Wastewater generated can be treated before disposing of into the water bodies. If the treated wastewater levels fall under the safe range, they can be reused.

Many industries generate wastewater and directly dump it into the water body. This leads to pollution, and the water present is unfit for use. If wastewater is not adequately treated, it can cause havoc. As a result, finding an appropriate industrial wastewater treatment is critical. The reuse and treatment of wastewater are vital in maintaining this resource for future generations.

This is where a water treatment plant comes into play, as it can assist commercial and industrial facilities to become more environmentally friendly and compliant with their wastewater disposal. Depending on the type of wastewater generated, there are different types of wastewater treatment plants that can treat the sludge coming in at various stages and reduce its toxicity. In this blog, let us understand these plant types a little more in detail, and also look at a few ways to maintain them.

Wastewater Treatment Plants

Untreated wastewater should not accumulate in any way. It consists of decomposed organic matter. If kept for a longer time, the organic matter can produce foul-smelling gases that can be toxic to the environment. Besides this, it also contains other toxic compounds that can be harmful if exposed to the environment. Therefore, it is essential to remove wastewater from its source and clean it. Moreover, due to water scarcity, reuse is an excellent option.

While the overall functionality of a treatment plant operates similarly, the wastewater treatment systems can be divided into multiple categories. It is usually based on their operational functionalities and the effluent source coming into the plant.

The various types of plants are as follows :

Sewage Treatment Plant (STP)

Effluent Treatment Plant (ETP)

Common and Combined Effluent Treatment Plant (CETP)

Sewage Treatment Plant

Sewage treatment is a multi-stage process designed to treat domestic waste from households, commercial buildings, malls, educational institutes, hospitals etc. Sewage wastewater can include a combination of greywater (wastewater from baths, sinks and other non-toilet plumbing fixtures) and blackwater (wastewater from toilets containing faecal matter).

How does it work?

When wastewater arrives at a sewage treatment plant, it is filtered as part of the pre-treatment process. A pre-treatment is done before it moves to three combative stages of treatment: primary, secondary, and tertiary treatment.

In the primary treatment phase, the water settles in a tank, where solid organic matter accumulates at the bottom while lighter matter floats to the top, making removal easier. After the clarification process, the sludge moves to the secondary phase, also known as the activated sludge process.

During the activated sludge process, the aerators pump oxygen into the chamber. This helps bacteria digest the organic matter, giving wastewater its distinct appearance and smell. The water further gets treated into the tertiary stage.

The tertiary stage is the most advanced stage, where the sewage containing toxic microbes is disinfected. During this stage, wastewater is passed through different filters, which filter out microscopic particles. The ultraviolet (UV) lights kill bacteria and viruses and remove infections.

Once the wastewater passes through all three stages, it is entirely safe to discharge into the environment.

Effluent Treatment Plant (ETP’s)

ETP is a wastewater treatment process (WWTP) used to treat wastewater generated from pharmaceuticals, textiles, and chemicals where extreme water contamination is possible. It plays a significant role in the treatment of industrial wastewater along with domestic sewage. Inorganic matter, heavy metals, oil & grease, suspended particles, and other contaminants are treated in the ETP plant.

The construction and development of an ETP are crucial for the ecological development of industrial parks. These plants are designed to handle effluent with high pollution levels, which is more complex to degrade. Each industry releases effluent with varying characteristics daily, unlike sewage treatment. Hence, the need for daily monitoring and customised treatment solutions plays a crucial component in proper treatment.

How do ETPs work?

Like STPs, even ETPs contain various stages where the water is treated. The steps are preliminary, primary, secondary and tertiary treatment.

The preliminary technique aims to eliminate as much solid physical matter as possible before sending the effluent to be treated further.

In the primary stage, the removal of solid waste and organic matter is the first step in the treatment process. Chemicals are added to break down the solid waste present in sludge. After the solids are broken down and eliminated from the sludge, the wastewater moves to secondary treatment.

Under secondary treatment, suspended particles and any biodegradable matter are removed using a combination of chemical and biological processes. Further to remove any final traces of solids or contaminants from the effluent, it undergoes tertiary treatment, which employs a variety of physical, chemical, and biological processes.

Common Effluent Treatment Plant (CETP)

Several industrial clusters across India have installed and are operating common effluent treatment plants (CETPs). They help small-scale industrial facilities that can’t afford individual treatment plants save money on effluent treatment, improve collective treatment, and save money on land.

Optimal working conditions for effluent treatment to meet discharge standards are essential for any CETP.

CETPs are classified into two categories.

Homogenous: Industries producing similar goods in that industrial area contribute. E.g. tanneries, paper, etc.

Heterogenous: industries producing widely divergent goods are placed together. E.g. chemical, dairy, soft drink, canneries, pharmaceuticals, etc.

How does CETP work?

Like other treatment plants, CETP consists of various stages where the sludge is treated. The steps include a preliminary, primary, secondary and tertiary stage. The treatment on each stage is more or less similar, just like other treatment plants.

After the sludge is treated, there are different ways to dispose of CETP effluent. Some disposal modes are surface water bodies, land irrigation, and public sewers. Before discharging the effluent, it undergoes a standardization test to ensure no hazardous chemicals enter the water body.

WasteWater Treatment Plant Maintenance

An efficient running of a wastewater treatment plant requires periodic maintenance and daily checks of the system. Failing to do so can lead to blockage of pipelines and even failure of some parts.

Other factors that might cause a problem in the smooth functioning of the plant could be high COD/BOD levels, odour issues, treated effluent not meeting standard toxicity levels and many others.

Organica Biotech provides a host of bioremediation based solutions for different wastewater treatment plants to overcome these problems and ensure their systems operate smoothly.Our wastewater treatment technologies are an alternative for effective sewage treatment and industrial wastewater treatment. With our range of nature-friendly solutions, including Cleanmaxx, you can reduce sludge volume, cut down operational costs, curb foul odour and significantly lower COD and BOD levels in the water.

You now don’t have to worry about the costly maintenance in the current system as our solutions are hassle-free and require no physical changes in the system.

We must be environmentally responsible and treat the wastewater using techniques that do not cause harm to the environment. By understanding different types of wastewater treatment plants, take a step ahead and protect the ecosystem.

Post by Karen Sam