BIOLOGICAL TREATMENT OF DISTILLERY WASTE FOR POLLUTION-REMEDIATION

The biological treatment of spent wash from molasses distilleries was investigated. Analysis of raw spent wash showed it to be a recalcitran t waste, with a high COD of 85,170 mg/l and containing inhibitory phen olic compounds. Reverse phase thin layer chromatography identified gal lic and vanillic acid present in spent wash. The fungi Geotrichum cand idum, Coriolus versicolor; Phanerochaete chyrsosporium and Mycelia ste rilia were screened for their ability to decolourize spent wash and to reduce the COD level. A 10 day pretreatment with Geotrichum candidum at 30 degrees C resulted in reducing the COD by 53.17% and total pheno ls by 47.82%, enabling other bioremediating organisms to grow. Coriolu s verisicolor immobilized in a packed-bed reactor reduced the COD of s pent wash by a further 50.3% giving an overall reduction in COD of 77% to 15,780 mg/l. A small amount of decolourization was achieved (4.2%) , although the spent wash was still coloured. Present studies are enco uraging and indicate that it is possible to bioremediate spent wash us ing a multi-stage treatment process involving an intial pretreatment s tep with Geotrichum candidum.