Compact Extended Aeration Reactor (CEAR) – Study on Nitrogen Removal

Nutrient compounds are becoming increasingly significant in wastewater management, since their concentrations are observed to be escalating in the past few years. This condition is mostly due to the human activities, from the production and use of nitrogen fertilizers to the burning of fossil fuels in automobiles, power generation plants, and industries. Concern over this matter, the Department of Environment (DOE) Malaysia had significantly reduced the discharge limit for nitrogenous compound such as ammonia-nitrogen and nitrate through amendment of Environmental Quality (Sewage) Regulation 2009. Thus, the purpose of this study is to produce a new integrated wastewater treatment system that can help in meticulously remove nitrogen and produce high quality effluent. To achieve this, an integrated reactor consists of two - (2) aeration tanks, one - (1) anoxic tank and one - (1) clarifier was designed. This reactor, which is known as Compact Extended Aeration Reactor (CEAR) was operated under SRT of 40 days and was filled with approximately 330 litres of wastewater. During operation of the reactor, synthetic wastewater made from dilution of finely grinded dogs‟ food was used to imitate medium strength domestic wastewater, thus creating more consistent organic loading. Sludge from UTP sewage treatment plant was also added inside the reactor as the source of biomass and total of 48 litres/day recycle rate was imposed on the reactor. After acclimatization period over, it is found out that the effluent discharge of ammonia-nitrogen and nitrate become consistent at 0.5 mg/L and 0.3 mg/L, respectively. This result is true for both incoming flowrate of 8 mg/L and 10 mg/L.