Abstract:
A furnace equipped with a removable measuring scale in the side was applied to study on the shrinkage characteristics of semicoke/coke under gradient temperature during coking process. 1500g coking coal was used in the test. The effects of coking time, central temperature, heatingup rate and gradient temperature on lateral shrinkage were studied under different heating rates (1.0℃/min, 1.5℃/min and 3.0℃/min) and densities (880kg/m3 and 1080kg/m3), respectively. The results show that the coal begins to shrink at a central temperature range of 280℃~360℃ and ends at about 900℃. The lateral shrinkage is in a range of 5mm~8.5mm and lateral shrinkage ratio is 7%~12%. Generally, the gradient temperature increases and lateral shrinkage decreases with increasing heatingup rate and density. The central temperature of beginning shrinkage, the second shrinkage peak, gradient temperature of different locations and shrinkage coefficient of coal decreases with the increase of heating rate. The central temperature of beginning shrinkage and gradient temperature of different locations increase with increasing density. But the increase of density has no influence on shrinkage coefficient and shrinkage peak. In addition, the temperature rise rates at different locations are different during different coking stages.