Package treatment plant utilising RBC

In 1985, it was estimated that about 5.3 per cent of the population of Malaysia had access to centralised sewerage treatment plant. About 84.5 percent had some form of treatment while 10.2 percent had no sanitation facili­ties whatsoever. Especially for those in the urban or peri-urban fringes and run-down slums of large towns and cities without any proper sanitation facilities compact package on­site domestic wastewater treatment plant could be the answer to their sanitation woes. A full scale sewage treatment plant with pri­mary and secondary sedimentation tanks incor­porating a rotating biological contractor(BBC) as secondary treatment was employed to evalu­ate the process performance and to develop kinetic models when treating domestic wastewater. RBC was chosen as secondary treatment due to its carbonaceous and ammonia nitrogen removal efficiency, low power consumption, greater flexibility, low retention time, low sludge production and low mechanical main­tenance requirements, The RBC was operated at different organic loading rates that ranged from 13.1 to 27.8 gCOD/m 2/d. The overall carbonaceous and ammonia nitrogen removal percentages were from 84 - 92 percent and 82 - 93 percent respectively. Steady state kinetic models for carbonaceous removal WclS used to obtain the kinetic con­stants to be used as a design aid.