Advanced Treatment Systems
Advanced treatment systems differ from conventional systems in a number of ways, the primary difference being that they further treat the wastewater before it is dispersed to the soil environment. Advanced treatment systems incorporate carefully designed treatment steps, and create conditions to facilitate a consistently high degree of treatment. Many advanced treatment systems control flow through the system using pumps and timers to avoid overloading the treatment and final dispersal components during periods of high water usage, or “peak flow” conditions, which could occur during a morning rush of activity or when many guests are in the home.*
The treatment provided by the advanced treatment system serves to further reduce the “strength” of the wastewater, or the solids, fats, oils, and greases (FOG) that are suspended in the effluent. This step may also contribute to reductions in pathogens and/or nutrients in the wastewater depending on the design and configuration of the system. Systems that function to reduce nitrogen generally recirculate the effluent back to the septic tank or to a separate recirulation step where raw effluent and treated effluent are mixed, creating conditions that facilitate the removal of nitrogen by beneficial bacteria. Technologies are initially chosen based on the level of treatment that is required, as not all technologies will effectively achieve nutrient and/or pathogen reduction. Treatment technologies achieve the best results when receiving wastewater with certain chemical and microbiological characteristics, and so the components are chosen and paired up with this in mind. Site constraints may also dictate the potential use of some technologies. For instance on small lots with existing homes and failed septic systems, the advanced treatment technologies with the smallest footprints are most commonly used as replacement systems. Advanced treatment systems generally require annual or semi-annual maintenance activities in order to function properly; these maintenance activities should be performed by a trained and qualified service provider.*
Aerobic Treatment Units
Aerobic treatment units (ATUs) rely on air injection systems and blowers to create an oxygenated (aerated) environment, which is able to support bacterial populations that break down organic material. This aeration process produces an effluent that is lower in total suspended solids (TSS) and biochemical oxygen demand (BOD) than that of conventional systems. The injection of air into the ATU agitates the wastewater, so solids are readily mixed with the bacteria, facilitating digestion of the organic matter by bacteria. There is a step in the process where any settled solids and bacteria are returned back to the aerobic portion of the tank for mixing and additional treatment. A clarification step is also a part of the treatment, allowing for solids and bacteria to settle out of the wastewater prior to distribution to the drainfield, helping to ensure that effluent leaving the ATU contains as few solids and organic matter particulates as possible.*
Orenco Treatment Systems
Orenco's Advantex Wastewater Treatment System is a compact unit that generates effluent clean enough to use for subsurface irrigation. Go to the Orenco Website to find out more.
Norweco Treatment Systems
Norweco's Singulair Wastewater Treatment System is a state-of-the-art treatment system that quietly and efficiently treats all incoming wastewater by automatically returning harmless effluent to the environment in just 24 hours. Go to the Norweco Website to find out more.