Septic Tank as an Aerobic Method of On Site Sewage Treatment

A septic tank is a type of on-site sewage treatment system that is commonly used in rural areas or areas that are not connected to a centralized sewage treatment plant. It is designed to treat and dispose of household wastewater, including human waste, by breaking down the organic matter in the sewage and releasing treated water into the ground.

Anaerobic vs. Aerobic Treatment

There are two main methods of sewage treatment: anaerobic and aerobic. Anaerobic treatment relies on bacteria that do not require oxygen to break down organic matter in sewage. This process produces methane gas and sludge as byproducts. Aerobic treatment, on the other hand, relies on bacteria that require oxygen to break down organic matter. This process produces carbon dioxide and water as byproducts.

Septic Tank as an Aerobic Treatment System

A septic tank is designed as an anaerobic treatment system, but it also incorporates aerobic treatment processes. The tank itself is a large underground container that is usually made of concrete, fiberglass, or plastic. The tank is divided into two or three compartments, and the wastewater flows from one compartment to the next through baffles or other barriers.

The first compartment of the tank is where the majority of the anaerobic treatment takes place. The wastewater enters the tank and settles to the bottom, where bacteria break down the organic matter in the sewage. The byproduct of this process is a layer of sludge that accumulates at the bottom of the tank.

The second compartment of the tank is where the aerobic treatment takes place. The wastewater flows from the first compartment into the second compartment, where it is exposed to oxygen. This allows aerobic bacteria to grow and break down any remaining organic matter in the sewage. The byproduct of this process is a layer of scum that accumulates at the top of the tank.

The final compartment of the tank is where the treated water is stored before it is released into the ground. The treated water is gravity-fed into a drain field, where it percolates through the soil and is further treated by natural processes.

Conclusion

In summary, a septic tank is an on-site sewage treatment system that uses both anaerobic and aerobic treatment processes to break down organic matter in household wastewater. The tank is designed as an anaerobic system, but it also incorporates aerobic treatment in the second compartment. The treated water is then released into the ground where it is further treated by natural processes.