The Effect of Using Microorganisms on Sludge Reduction in Wastewater Treatment Plant

Sludge dewatering and treatment may cost as much as the wastewater treatment. Usually large proportion of the pollutants in wastewater is organic. They are attacked by saprophytic microorganisms, i.e., organisms that feed upon dead organic matter. Activity of organisms causes decomposition of organic matter and destroys them, where the bacteria convert the organic matter or other constituents in the wastewater to new cells, water, gases and other products. The main objective of the present search is to improve an effective way and applicable methods of sludge volume reduction so as to increase the capacity and improve quality of the treatment in lagoon, thickener...etc. A bench scale model was set at the environmental engineering department laboratory, in the Faculty of Engineering, Zagazig University. Samples of wastewater were collected from Aslogy wastewater treatment plant, Zagazig, Egypt. The using bacteria embed on granular delivered as powder. Two runs of experimental works have been done using bacteria with different doses (0.5, 1, 2 & 4 gm/l) for up to 8 weeks. Experimental results were indicated that there is no remarkable improvement in COD removal ratio than reference sample in wastewater by adding the used microorganism even at dose of 4 gm/l. However, the sludge volume showed remarkable decrease, due to the use of the bacteria to about 63% more than that of the reference sample.