Enhancing the sludge reduction potential of dairy waste activated sludge by various physic chemical pretreatments

Abstract

This study presents the findings obtained from laboratory scale experiment of a series of three different sludge disintegration methods like low temperature thermoalkaline LTTA disperser alkaline and sonicationalkaline an assessment of pretreated sludge biodegradability and the performance of semi continuous anaerobic reactors of pretreated sludge Firstly the laboratory scale feasibility studies on LTTA pretreatment were investigated and it was carried out at 50 to 80C during 6 to 48 hrs At optimized condition 60C with pH 12 COD solubilization and suspended solids SS reduction was 23 and 22 higher than that of control Biochemical Methane Potential BMP assay results of pretreated sludge confirmed that nearly 51 higher biogas production than control Thus 60 C with pH 12 was chosen for semi continuous Reactors Two identical laboratory scale semi continuous reactors with a working volume of 4L were used at mesophilic temperature 35 C Among the two one is designated as Control Semi Continuous Anaerobic Reactor which acts as control and another is designated as Experimental Semi Continuous Anaerobic Reactor where sludge reduction was carried out Sludge retention times SRTs of 20 15 and 12 d were sequentially tried to investigate the performance of theanaerobic digestion of the pretreated sludge newline newline