The proprietary Modular Anoxic Aerobic Digester (MAAD) process by BioShaft integrates an anaerobic digestion tank with the T-MBBR System. The raw pre-screened wastewater undergoes partial treatment through the anaerobic tank before it’s treated through the T-MBBR System. Depending on the application, most or all of the sludge effluent from the system’s secondary clarifiers is sent to the anaerobic tank for complete digestion.
The MAAD process is particularly suited for industrial wastewaters with moderate amounts of fat and proteins which increase the organic loading and cause scum formation in the aeration tanks and settling problems in the secondary clarifiers. The MAAD System is also particularly suited for wastewaters with variable composition and occasional spikes in the concentrations of certain compounds. Examples are wastewaters from food processing plants, dairies and slaughter houses.
When used in municipal wastewater treatment applications, the MAAD process reduces sludge generation by more than 95% compared to the conventional biological wastewater treatment systems. A municipal MAAD system does not produce daily volumes of sludge. Instead, all of the sludge from the secondary clarifiers in sent to the anaerobic tank to be digested. Only inert solids begin to accumulate inside the anaerobic tank. These solids are cleaned out once every few months. The anaerobic digestion step reduces aeration therefore power consumption requirements.