Recycling of granite waste and burnt coal cinder for the preparation of sintered permeable bricks

Abstract The sintered permeable brick was prepared using granite waste and burnt coal cinder (BCC) as raw materials to ensure the utmost utilization of both solid wastes. The effect of various parameters, such as the proportion of raw materials, granite particle size and sintering temperatures on the properties of the permeable brick were studied, and the relevant sintering mechanism was clarified. The differential scanning calorimetry curves indicate that the mixture of granite waste and BCC begins to melt at a lower temperature, which is lower than the temperature for melting them alone, so the use of them to prepare sintered bricks will reduce energy consumption. The optimal conditions for the preparation of the permeable bricks were determined as the mass ratio of granite waste to BCC of 80: 20, sintering temperature of 1150–1175°C, and granite particle size of .9–1.25 mm. It was found that the permeability and the flexural strength of the samples can reach 3.41 × 10 ⁻² cm/s and 4.2 MPa, respectively, which both exceed the requirements specified in the national standard of China.