Experimental options for determining the temperature for the onset of sintering of coal ash

This paper presents a comparison of techniques that can be used to obtain the sintering temperature of coal ash. These techniques are thermal conductivity analysis (TCA), thermome-chanical analysis (TMA), the compressive strength test (CS), and a proposed new technique called the pressure-drop technique. Generally, the results from these four techniques compare well and showed sintering temperatures in the range of 600-1000 degrees C. These temperatures reflect the onset of strength development in coal ash deposits. An analysis of the results indicates the compressive strength and thermal conductivity techniques are believed to overestimate the sintering temperature of coal ash as measurements were conducted at temperature intervals and these measurements depend on treatment time. Thermomechanical analysis and pressure-drop techniques are believed to provide a more accurate indication of the sintering temperature due to the constant monitoring of ash structural changes and the inherent sensitivity of the methods to structural changes.