Determination of the Bacterial Compositions in the Bio-Drying Process of Sewage Sludge from Wastewater

Abstract

The aim of this study is to determine the bacterial compositions during the bio-drying process of sewage sludge. Bio-dried products and sewage sludge were randomly collected from the Wupa wastewater/sludge treatment plant in Idu Industrial area Abuja, Federal Capital Territory, Nigeria. A mixture of sewage sludge and sawdust that were bio–dried and cured before this experiment were composition of the bio–dried product. The bacterial communities were analyzed in the laboratory using Pour Plate Technique to examine the total bacterial present in the sewage sludge bio-drying material (SSBM) and the bacterial were later isolated using other techniques like Oxidase test, Catalase test, Grams Staining technique and Spread Plate Technique. Evaporation of free water and water formation was determined by humidity gauge and moisture-oven drying method. From the results obtained, Acinetobacter was the most abundant bacterial during the initial and final thermophilic phases (43% and 37%) respectively. Bacillus was the most abundant amid the cooling stage (53%). The water evaporation and water generation rate were credited to the degradation of organic content of the SSBM and heat produced by bacterial activities. From this study, there is a clear indication that the bacterial density grades that increase the temperature of the SSBM during the bio–drying process reshaped the bacterial communities.