Treatment of Effluent with an Anaerobic Aerobic Effluent Treatment System

Abstract

Today energy and clean water is a requirement in all societies worldwide to run productive processes. This affects the natural environment negatively and requires establishing more environmentally sustainable processes to decrease dependency and preserve the natural environment. In this research approach a laboratory anaerobic aerobic effluent treatment system was designed, built, and started up with wastewater. After start-up the system was operated with prepared milk waste, liquid cow manure and wastewater at a hydraulic retention time of 3 days and 6 days.  The laboratory anaerobic aerobic system was able to degrade the chemical oxygen demand, total solids and total suspended solids of all three influent liquids up to 95% and 98% for the 3-day and 6-day hydraulic retention time. Maximum total solids removal was 87.89% and 92.43% for the 3-day and 6-day hydraulic retention time. Total suspended solids removal yielded a maximum of 99.87 and 99.93% for the 3-day and 6-day hydraulic retention time. The anaerobic sludge blanket reactor of the system operated at a temperature of 38°C and a pH between 7.5 and 8.2 achieved a biogas CH4 content of 65% ± 5% and a maximum total biogas production of 2.23 ml/h for the milk waste at a 3-day hydraulic retention time and a minimum biogas production of 1.36 ml/h for the waste water the 3-day and 6-day HRT respectively. The operation of the designed laboratory anaerobic aerobic effluent treatment system showed that it is capable of reducing the effluent loading of a variety of waste streams as well as producing biogas that can be converted into bio-energy.