[Investigation of the efficiency of activated sludge reactor with fixed bed in biological removal of methyl-tributyl ether from synthetic wastewater]

ABSTRACT

Methyl-tributylether [MTBE] is a volatile organic compound which has detrimental effects on the environment, surface water and groundwater resources and it can change the taste of drinking water. The aim of this research was to determine the efficiency of activated sludge reactor with fixed bed in biological removal of methyl-tri-butyl ether from synthetic wastewater. This was an intervention-applicable study. The applied reactor was made of plexiglas and after transfer of activated sludge to it; the system ran for 4 weeks discontinuously. During a period of one month, concentration of glucose of the solution reduced and that of MTBE increased. 32 days after running the system, the whole COD input was provided through MTBE. COD, TSS, MLSS, SVI, temperature, PH, and dissolved oxygen parameters were analyzed in duplicate forms by excel software. The results of this research indicated that by increasing the organic input load, the efficiency of the reactor decreased to some extent. The mean values of efficiency of COD removal during hydraulic remains of 4, 6, 8 and 10 hours were 82.7, 92.45, 95.97 and 96.1%, respectively. The results of this study showed with organic loadings up to 3 and 4/5 kg COD/m 3.d, the combined activated sludge reactor with fixed bed is capable of meeting the standards of household and industrial wastewater according to the standards of Environmental Protection Organization of Iran as to effluent wastewater COD for discharge in accepting water resources. Therefore we can conclude that the activated sludge reactor with fixed bed is an efficient, reliable and applicable technology for the treatment of strong wastewater