Extended Aeration Activated Sludge Systems

An extended aeration process has many advantages over other activated sludge processes. The longer sludge age makes for a stable, easy to operate process that is less prone to upsets over a conventional activated sludge plant with a shorter sludge age.

The stable process equates to less equipment to maintain and less operator hours spent on process operation and optimization. Extended aeration systems also produce much less sludge than other systems due to the longer sludge age and in most cases produces a Class B sludge that doesn’t require further digestion which reduces sludge handling costs.

There are several options when it comes to an extended aeration process for wastewater treatment. Of these, the most popular are the Bioworks system, oxidation ditches, sequential batch reactors, and other lagoon treatment systems. Of these choices, the Bioworks system has the lowest capital and operating costs. Oxidation ditches use mechanical aerators that cannot match the efficiency of a fine bubble aeration system and require extensive concrete works that increase capital costs. An SBR process requires more energy as the aeration system has to complete the oxidation process in a shorter time due to cycling which does not allow for optimization of aeration system. Capital costs are larger because of the concrete works and a larger air flow to aerate in a shorter time require larger blowers. Other lagoon treatment systems either use lower efficiency mechanical aerators or outdated fine bubble diffusers that are approximately 20% less efficient than the Bioworks Oxiworks diffuser and are more expensive to purchase and install.

By combining an inexpensive lagoon treatment option that saves money over concrete for a treatment process and a proven diffuser system that outperforms the competition Bioworks provides a system that outperforms others in simplicity of operation, capital costs, and operating costs.