Aerobic treatment – August 2019

Aerobic treatment – August 2019
Share on print

Contact the author

Location of the case study

Bangladesh - Cox's Bazar


Main treatment objectives

BOD/COD reduction, Nutrient reduction, Pathogen reduction

Capex per design input flow

2022 USD/m3/day

Opex per real input flow


Required space


Description of the treatment process

The anaerobic baffled reactor is used as pretreatment, to remove solids from the waste stream. The waste then moves to two reactor tanks in series. The aeration of the incoming faecal sludge in the a reactor tanks leads to the breeding of bacteria that metabolize the organic content (COD/TOC (Total Organic Content)) together with the oxygen, turning the organic content into a gas (carbon dioxide).

The supernatant from the two reactor tanks is transferred to a settling tank, where the remaining solids are separated. The supernatant of the settling tank is then passed through a glass bead filter, which is regularly backwashed, for the removal of parasites and parasite eggs. Finally, the liquid is disinfected by chlorine or UV. Sludge from the settling tank is added to the reactor tank. Reactor tank sludge is treated by anaerobic digestion or lime treatment.




Notify of
Inline Feedbacks
View all comments