Utilization of waterworks sludge in the production of fired/unfired water permeable bricks

摘要

Waterworks sludge was used as raw material to make fired water permeable bricks (WPB) and unfired water permeable bricks (WPB). Results show that when 30%～40% sludge was added with 30%～35% ordinary sands ranging from 1.0 to 1.4 mm and some other materials, pressed at 30 MPa and then sintered at 1150°C for 1h, the compressive strength (CS) and permeability coefficient (PC) of produced fired WPB were 36.53 MPa and 1.08×10~(-2) cm/s respectively. When the ratio of waterworks sludge increased from 20% to 35%, the CS of the unfired WPB decreased but stayed above 20 MPa, while the change of PC is insignificant.