Apparatus for determining high-temperature, high-pressure coal plastic behavior under rapid heating conditions

This paper describes a rapid‐heating, fast response plastometer for measuring the plastic behavior of softening coals under a new range of conditions of industrial and scientific importance previously unattainable with conventional instruments. The results give insights on feedstock transformations in high‐temperature processes such as gasification and combustion. The instrument determines the torque required for constant rotation of a thin disk embedded within a thin layer of coal heated between two parallel, metal plates. Heating rates, final temperatures, and sample residence times at final temperature can be separately selected and controlled over the ranges 40–800 K/s, 600–1250 K, and 0–40 s, respectively. The device is enclosed in a vessel designed for hydrogen or inert‐gas pressures up to 10 MPa. Data from this apparatus are consistent with a physicochemical description of coal plasticity and with predictions from a simple model. Application of this instrument to other thermoplastic solids should b...