Application of the biological reactor with fixed media (IFAS) for removal of organic matter and nutrients in small communities

ABSTRACT

The purpose of this study was to evaluate the performance of the small-scale integrated fixed-bed activated sludge (IFAS) method in pre-built reactors having two different models, running for two months on a weekly basis. Some operational parameters such as HRT, MLSS, DO and biomass mass weight have been averaged, which is for HRT of 9 h. Also, average values of parameters such as COD, BOD, TKN, NH₄-N, TP, TSS, faecal coliform and total coliform have been evaluated to determine reactor performance. The average removal efficiency for BOD₅, COD, TP, TKN, NH4-N, TSS, faecal coliform and total coliform was 70.5%, 79%, 49%, 64%, 80%, 73% and 87%, respectively; these results were obtained in the absence of any disinfection. The minimum timeframe for optimising the system is about two weeks. This article also discusses the capacities and problems of the installed reactors to best select systems for small-scale wastewater treatment. The results showed that the treated wastewater had acceptable results in terms of microbial load, in the absence of any disinfection.

KEYWORDS:

• Integrated fixed-bed activated sludge (IFAS)
• domestic wastewater
• nutrient removal
• BOD₅
• COD

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This paper was supported financially by a grant (No.93120416) from the Guilan University of Medical Sciences, Rasht, Iran.