How Do Wastewater Treatment Plants Work?

What Is Wastewater Treatment?

Wastewater management is one of the most cost-effective pollution control methods, yielding a superb return on investment for the environment. Effectively treating wastewater is a necessary component in minimizing waterborne illness – protecting human health and the environment in the process.

The United States has a solid infrastructure for streamlining wastewater efficiency. This includes an abundance of functional sewer systems, pumping stations, and wastewater treatment plants. The main purpose of setting up a wastewater treatment plant is to catalyze nature’s way of unclogging its adversely clogged systems.

Simply put, a sewage treatment plant cleans wastewater faster and more efficiently than nature ever could. After water is treated, it is discharged back into natural water bodies for later precipitation. In essence, it speeds up nature’s own water cleansing cycle.


A Brief Description of How Nature Cleans Polluted Water

People have been dumping sewage into fresh water supplies since ancient civilizations created basic sewer lines. Rivers, wells, and ponds suffered a similar fate. Under ideal circumstances, the natural purification process could clean and distill the dirtiest pollutants and produce clean rainwater.

However, this process is contingent on natural organisms, an interdependent ecosystem, and climate conditions. Nature dilutes contaminants to produce clean water. Molecules move from an area of high concentration into an area of low concentration. Living organisms from different kingdoms, such as plants, bacteria, worms, and fish assist in the decomposition of contaminants.


How Is Wastewater Treated?

Recycled wastewater helps maximize water treatment systems. The wastewater treatment process is designed for efficiency, and it is completed in two main wastewater treatment steps. The first step majorly depends on the forces of physics to decant and separate solid particles from the liquid. The secondary step comes after solids are eliminated and biological processes manifest to separate elements and purify water.


Wastewater Treatment Process

The Primary Wastewater Treatment Process

Before a wastewater treatment plant lets in any volume of sewage, it must pass the new influx through a screen. The screening process, which is the first, removes large objects in the mixture. Large objects like sticks, hair, plastic products, and rags clog and damage the sewer lines and pipes. Heavier objects, especially small-sized particles with higher densities than water, like stones and sand are eliminated via decantation. Some communities are more likely to have high amounts of solid participles draining into their sewer systems. That is why newer treatment plants emphasize ample grit storage.

After successfully eliminating large solids and the dense, sunken solids, you have to remove the little floating solids as well as the organic and non-organic matter. The sedimentation stage needs to take place in a tank with minimum disturbance. The slow-paced stage lasts longer than the previous two, and the suspended matter finally sinks below to form sludge of biosolids. The sludge is supposed to be removed for proper disposal. After pumping sludge out of the tanks, most supremely efficient treatment plants treat it further to make fertilizers.

Primary treatment of wastewater alone is powerful enough to eliminate the majority of harmful contaminants. It goes a long way to help ecosystems balance out the adverse effects of large populations surviving on limited resources. However, major cities and populated towns must make an extra effort in securing the quality of their environment and availability of clean water supply. Failure to treat the water further for the removal of poisonous and organic contaminants could cause waterborne diseases.

In such densely populated environments, the water is fully purified for reuse since disposing it to the environment would still cause health concerns. Furthermore, in secondary treatments, the process results in the creation of commercially viable byproducts.


The Secondary Wastewater Treatment Process

This phase requires a well-designed sewage treatment plant for ultimate cost efficiency. It manipulates the bacteria present in the sewage it treats to eliminate 85 percent of organic matter present. The liquid mixture that leaves from the decantation tank is still considered effluent and contaminated with disease-causing organisms. It is pumped into the facilities that majorly depend on:

  • The trickling filter process.
  • The activated sludge process.

The effluent goes through a trickling filter which is set by arranging a bed of rocks. As modern research into the sustainable use of plastics advances, you can now set up a wastewater treatment plant and use synthetic media to make up the trickling bed. The trickling bed facilitates the gathering of the bacteria for multiplication.

When the bacteria gather and multiply, they manage to consume most of the organic matter. The cleaner water is more viscous, and it trickles out into another chamber. Afterward, the cleaner water, which is still too contaminated for household reuse, gathers at more decantation tanks. The tanks are meant to minimize the high concentration of bacteria.

How is wastewater treated without the activated sludge mechanism installed in a wastewater treatment plant? The activated sludge is the faster one between the two principal wastewater treatment steps. It guarantees a faster process by increasing the number of cultivated bacteria while increasing air supply to them for accelerated multiplication. The bacteria eat up the suspended organic material way faster than it takes a trickling filter sewage treatment plant.

Among the two secondary wastewater treatment steps, most modern environmental enthusiasts prefer the activated sludge process. How is wastewater treated in current times? The typical modern-day wastewater treatment process will involve pumping the decanted effluent into an aeration tank.

The final step of the secondary process involves disinfecting. The disinfecting agent is chlorine, and it makes water safe for drinking.


Improved Wastewater Treatment Monitoring

High Tide Technologies offers SCADA solutions for wastewater treatment plants that allow for more efficient and effective wastewater monitoring and reporting. Our systems deliver the data that operators need to make informed decisions about their equipment and processes.

Contact one of our distributors to learn about how one of our customized cloud-based SCADA systems can help maximize a wastewater treatment plant.