Abstract:Sawdust, coal gangue and paper sludge were chosen as pore-forming agents of sintered shale brick. The pyrolysis behaviors of different forming agents were studied and the influences of the agents on bulk density, compressive strength, porosity, and water absorption properties of the shale brick were also investigated. It is shown that, with the increase of the dosage of sawdust, pore number of the sintered bricks and water-absorption increase, while the volume density and strength fall rapidly. Thus, the dosage of sawdust should be controlled within 6%. Because of poorer plasticity and lower ignition of coal gangue as well as low porosity rate of sintered bricks, the water-absorption of sintered bricks is poor, and decreases of density and strength are not obvious. In practical production, according to the requirements of brick-making heat and plasticity, a moderate amount of coal gangue can be added. The plasticity of the bricks improves as the dosage of paper sludge increases due to its good plasticity. However, excessive dosage of paper sludge will result in large shrinkage of sintered brick, low strength and high water absorption; therefore, the dosage should not exceed 7%.