Study of coke pore structure using image analyzer and mercury porosimeter

Cokes prepared using different coking conditions were measured by image analysis and by mercury porosimetry techniques. Using the VIDAS 2.0 image analysis system it is possible to determine coke pore structure parameters for the larger pores in sufficient number to enable representative and statistically valid data to be obtained. For a coke sample made in ERL's pilot coke ovens, at least 6 pellets should be used with 5 fields of view measured for each pellet to give reliable results. Coking conditions such as coal density and coking rate affect coke porosity parameters as measured by image analysis techniques and differences in hot properties of the coke such as high temperature strength and reactivity have been related to differences in pore size and cell wall thickness. Analysis of small pore properties by high pressure mercury porosimetry did not relate well to differences in conventional coke properties. Apparently macro pore structure plays a more dominant role than micropores in determining coke quality parameters