Ash Fusion and Flow Behavior.
MTI’s new LECO ash-fusion furnace system is used to measure ash fusion temperatures and slag flow behavior under controlled atmospheres.
Ash fusion furnace system
Fusion temperatures
The fusion temperatures measured are the four conventional ash fusion temperatures (AFTs) determined under oxidizing or reducing conditions (ASTM standard D1857). The AFTs measured include the initial deformation temperature, softening temperature, hemispherical temperature, and fluid temperature.
Viscosity Measurement - T250
Viscosity is the most important physical property of slag and ash, as it influences their ability to flow or develop strength. Using different viscosity models, MTI can predict the viscosity of a slag or ash. In some cases, actual physical measurements are necessary if the composition is outside the ranges where predictions are less accurate.
Viscosity of slags can be measured in either oxidizing or reducing environments. T250 is the temperature at a viscosity of 250 poise, at which slag begins to flow (and develop strength). The sample is placed in a furnace and heated at a steady rate. The test is monitored through the stages of melting; most tests are captured on video to better determine the T250.
The T250 method was tested using a National Institute for Standards and Testing (NIST) glass standard. The results are within 5% of the certified value.
T250 measurement test
Additive for Slag Flow Modification, lb additive per ton of coal