When it comes to household sewage treatment systems, there are generally speaking two different designs: septic and aerobic. Both work to begin the process of cleaning wastewater before sending it to a secondary treatment area. Depending on your property and your family’s needs, you may find an aeration system to be a much better fit.
How Anaerobic Septic Systems Work
The septic tank, creates a relatively undisturbed, anaerobic environment (which means there is little, if any, oxygen dissolved in the water) where heavier solids sink to the bottom, lighter fats, oils and greases rise to the top, and grey water is suspended between them. Bacteria works within this system to slowly break down the solid waste and allow relatively “clean” grey water to filter into a drain field. This system is designed to hold wastewater in the septic tank for about 24 hours before it moves on to the drain field, which is why excessive water use (like doing the entire family’s laundry in one day) can overload the septic tank and have devastating effects on your drain field. This system also requires a relatively large swath of cleared property to house the drain field, where the second phase of water treatment occurs.
How Aeration Systems Work
Where the septic tank creates an environment with minimal free oxygen in the wastewater, the aeration system is designed to introduce oxygen into the wastewater so that the bacteria living within the system will be able to break down the waste solids more quickly and efficiently. Aerators are devices used for introducing air into the sewage treatment system to mix and oxygenate the liquid. This causes the solids to break down much more quickly. The system is made up of three distinct chambers that filter and purify your household wastewater. The first, the pretreatment compartment (AKA the “trash trap”), functions much like your anaerobic septic tank, where heavier solids settle to the bottom and lighter FOGs (Fat, Oil and Grease) float to the top. From here, the water with suspended solids enters into the aeration compartment, where an aerator mixes and adds oxygen to the water. Finally, the water moves into a clarifier compartment, where any remaining solids settle to the bottom before the clean water is pumped out of the system. Typically, the water will then move into a smaller, secondary treatment system (like a drain field, but one that is smaller than those required by an anaerobic system).
Advantages of an Aeration System
An aeration system is ideal if your property does not have adequate space to house a drain field or if your soil prevents proper septic drainage, as much of Northeast Ohio’s clay-rich soil does. Aeration systems are often used in more urban settings, where properties are smaller. Additionally, an aeration system is often installed when the drain field of an anaerobic septic system is beginning to fail. The oxygen-rich water not only requires less secondary filtration, but it also works to actually breakdown and reduce the amount of solids clogging the drain field. Due to the efficiency and speed with which an aerator breaks down the solids in your septic tank, your system will be less effected by excessive water usage. An aerator is often a good choice for a larger family because it can better handle the output your family produces.