Technical Bulletin No. 0223: The Effect of Waste Activated Sludge Addition on Vacuum Filtration of Primary Clarifier Sludges

Waste sludge from high rate biological treatment is highly hydrous and exerts a detrimental effect on the de-watering qualities of sludge obtained from primary clarification. The degree to which this is the case has not as yet been well established by laboratory study. National Council Technical Bulletin No. 223 contains an evaluation of this adverse effect on sludge filtration for both low-ash and high-ash sludges. In addition, the effectiveness of common conditioning agents in overcoming this effect was evaluated. The information provided should be of value in the selection of dewatering systems and identifying their operating capabilities and unsolved problems.