Sewage Treatment Plant is the process of removing contaminants from wastewater & flat sewage, both runoff (effluents) & domestic. It includes a physical, chemical, and biological process to remove physical, chemical, and biological contaminants.
Its objective is to produce treated effluent and soil waste or sludge suitable for discharge or re-use back into the sewage plant.
Introduction: Types of sewage treatment plants:
1. A sewage treatment plant, also known as a wastewater treatment plant, is a facility that treats wastewater and sewage.
2. We treat the wastewater and sewage to remove pollutants and make the water safe for release back into the environment.
3. Various sizes of wastewater treatment plants can treat wastewater from residential, commercial, or industrial sources.
The main goals of wastewater treatment plants are:
Wastewater treatment plants can be constructed on-site or they can be constructed in conjunction with a municipal sewage system. This is because the facilities will be located close to where the wastewater originates. However, they can be designed to treat wastewater from many locations.
Wastewater treatment plants are operated by a public entity, usually the municipality where they are located.
How they work:
- Primary Treatment
- Secondary treatment
- Tertiary treatment
PRIMARY TREATMENT
Screen chamber:-
Screening is the primary unit operation that most wastewater treatment plants encounter.
We use a screen with uniformly sized apertures to retain particulates found in influent wastewater, which might otherwise harm equipment or prevent treatment units from operating properly.
The screen’s primary function is to remove course items from the flow stream. Normally, people clean bar screens by hand, although mechanical cleaning devices are sometimes available.
These cleaning devices are rakes that sweep the entire screen regularly, removing the solids for processing or disposal. We commonly arrange hand-cleaned racks at a 45-degree inclination to the horizontal to maximize the cleaning surface and make raking activities easier.
Collection Tank or Equalization Tank:-
Gravity carries the sewage water from the bar screen chamber into the Equalization tank, providing consistent flow and loading to a biological process essential for maintaining optimal treatment. Equalization (EQ) Basins maintain significant flow fluctuations to deliver constant influent flow to downstream processes.
To prevent the raw wastewater from becoming septic and to maintain solids in suspension, we require aeration and homogeneous mixing due to the additional retention time. Then, we pump the water to the Aeration basin using raw water pumps.
SECONDARY TREATMENT
Aeration Tank:
The Moving Aerobic Bio-Reactor is provided with a state-of-the-art’ diffused aeration system using Fine Bubble Membrane Diffuser. In this system, we affect aeration by installing porous diffusers at the bottom of the tank.
In the aeration process oxygen transfer takes place by molecular diffusion through the terrace film between air and liquid and increases in proportion to the interface area for a given flow, The surface area increases, and the rise velocity of the bubbles decreases with the number of bubbles. This factor contributes to the higher oxygen transfer capacity of diffused aeration systems.
We fill the Moving Bed Bio Reactor with high-quality self-supporting cylindrical-shaped media made of polypropylene. We generate bacterial growth by providing compressed air in Bio-Reactors (MBBR) and allowing them to attach to the PP media to form a fixed film. This film reduces 98% of BOD, COD, and organic pollutants.
TERTIARY Or FINAL TREATMENT
This treatment, known as the final or advanced treatment, involves removing the organic load left after secondary treatment and targeting the removal of nutrients from sewage, particularly to kill pathogenic bacteria.
Secondary sewage treatment plant effluents contain both nitrogen (N) and phosphorus (P). All fertilizers contain nitrogen and phosphorus.
Dumping excess levels of N and P can enhance plant growth in receiving waters, leading to algae growth in the water body receiving such waste. Algae growth may be stimulated causing blooms that are toxic to fish life as well as aesthetically unpleasing.
Before reusing or disposing of the treated effluent, we may need to remove residual, mixed, and colloidal elements present in the secondary treated effluent.
The goal of tertiary treatment is to provide the last treatment stage to improve effluent quality before it is released to the receiving environment, such as the sea, river, lake, or ground, or to improve the treated water quality to the point where it can be reused.
This phase eliminates organic material, SS, nutrients, pathogens, and heavy metals, among other contaminants.
In Short, the wastewater treatment process begins with screening to remove large objects such as rags, sticks, and bottles. The wastewater flows into a grit chamber where it settles out, and we remove the heavier particles. Then, it flows into a sedimentation tank where we remove the organic material as it settles out.
Advantages and disadvantages:
A plant that cleans the water using a network of tanks and filters is one of the most frequent sewage treatment technologies. The plant treats the wastewater by removing sediment, debris, and pollutants. The water is then disinfected before it is released back into the environment.
There are several advantages to using a sewage treatment plant. The plant can remove large amounts of sediment and debris from the wastewater. And will remove many pollutants, including bacteria and viruses from the source water. The plant can also disinfect the water before releasing it into the environment.
There are also several disadvantages to using a sewage treatment plant. The plant can be expensive to operate and maintain. The plant can also take up a lot of space. The water is also treated somewhat differently in many states.
Some states use membrane filters to remove particles, bacteria, and sediment from the water. Other states use chemical processes to remove these substances.
Conclusion.
We need to carefully treat and disinfect the wastewater generated by residential, commercial, and industrial sources before releasing it back into the environment. A sewage treatment plant is responsible for removing pollutants and debris from the wastewater to protect public health and the environment.
The plant also needs to ensure that it meets all regulatory requirements for the water before discharging it into a water body.
We take on projects such as sewage treatment plant design, installation, testing, commissioning, and maintenance.
(Note: This article is for illustrative purposes only and does not imply an endorsement of any specific product or company. It’s essential to research and evaluate options based on your specific needs and requirements.)