Oxidation Stabilization Ponds (aerobic, anaerobic)

Stabilization Ponds or better known as Oxidation Ponds are usually constructed in an empty opened land area to contain wastewater. It has become a common treatment process usually employed for use in small township communities and its main advantages largely depend not only on its low setup cost (without the need for huge investment) but also for its low operating cost. Similar like aeration basin used in industrial wastewater treatment plants, its main purpose is to contribute towards COD and BOD reduction.

There are generally 3 different types of stabilization ponds and each individual unit is classified based on its biological activity whether it is aerobic, anaerobic or combination of both. In order to ensure the effectiveness of the whole system and conformance to government regulations, the design of ponds is very critical whereby detention time is a major factor being taken into consideration. In an optimized setup done to ensure safe and reliable quality of wastewater discharge, usually the detention time of 90 to 120 days is required for optimal reliability.

In an aerobic stabilization pond whereby there’s a need to ensure oxygen is always available, the design part has to take loading rate as the critical measuring parameter. Mainly this is done in order to ensure that every liquid depth from the surface up to the bottom of the pond is sufficiently mixed and aerated. Other than that, a well-designed setup is also able to maintain high production of algae cells that contribute to waste material breakdown similar like in a biological treatment process.

For aerobic-anaerobic (facultative) ponds, the design methodology closely resembles the aerobic setup while for complete anaerobic ponds, it works very much similar like an anaerobic digester except that it doesn’t require mixing to be applied. Sometimes, the design team can even incorporate aerators or diffusers to the aerobic or facultative system and whether this is economical will largely depend on the implementation part. Somehow, regardless of which type of stabilization ponds that is selected, overall, the system must be good enough to prevent sludge accumulation, which can considerably degrade long-term performances when the amount of suspended solid content increases.

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