INTRODUCTION OF BIOREMEDIATION ABILITY INTO GRANULAR SLUDGE

Three 200 ml upflow anaerobic sludge blanket (UASB)-reactors were inoc ulated with sugar degrading granules. To impart 3-chlorobenzoate degra ding ability to the reactors, one was inoculated with the 3-chlorobenz oate (3-CB) dechlorinating Desulfomonile tiedjei, and the second recei ved a 3-CB dechlorinating consortium, consisting of D.tiedjei and a be nzoate degrading coculture of Syntrophus buswellii with Methanospirill um sp. No degradation of 3-CB was observed in the third reactor only i noculated with granules. After several months operation at a hydraulic retention time at 0.5 day, shorter than the reported generation time of D. tiedjei, the reactors showed increasing dechlorinating abilities . Activity tests done with granules from the control and the consortiu m-inoculated reactor showed no activity in the control reactor and no significant difference in the specific dechlorination rate with granul es from the top, middle- or bottom layer of the active reactor sludge bed, with or without carbon source added. This indicated that the adde d bacteria were immobilized in the granules and they were responsible for the dechlorinating activity. These results have important implicat ions for the use of pure anaerobic culture or defined microbial mixtur es in viable waste treatment processes.