A Study on Using Fluidized Bed Reactor for Treating Sanitary Sewage

Abstract

Fluidized bed reactor (FBR) is an attached growththe system used mainly for biological treatment of industrialwastewater of high organic content. These wastewaters areusually resulted from refineries and milk, starch, and olive oilindustries. The objective of this study is to investigate the use offluidized bed reactor for treating sanitary sewage. The study wasaccomplished using a pilot plant of the FBR. The pilot plant wasconstructed and installed in Hamdan Sewage Treatment Plant inBasrah governorate. That was to maintain continuous source ofsettled sewage which is the influent to the FBR. The period ofplant operation was nine weeks. During, this period, the plantwas operated at three phases of different conditions (up the flowvelocity and recirculation ratio). To study the performance ofFBR, the main measured parameters were; BOD, DO, VSS, pH,and temperature. The most important conclusions of this studyare; (1) the maximum efficiency of BOD removal is 78.6% whichwas obtained for hydraulic retention time (HRT) of 24min andupflow velocity of 1.59m/min, (2) the effluent BOD values duringphases-1 and 2 of plant operation match that of stabilizationponds and trickling filters and during phase-3 matches thatactivated sludge process, (3) during all operation phases, thevalues of effluent pH are within the limits specified in nationalstandards of secondary effluents, (4) as F/M increases, theefficiency of BOD removal decreases and the maximumthe efficiency of BOD removal (78.6%) was obtained at F/M ratioequals 23.47 day-1, and (5) the HRT of fluidized bed reactor is onorder of minutes, while, the values of HRT of activated sludgesystems and stabilization ponds are on the order of hours and days,respectively.