Experimental study of coal pyrolysis and hydropyrolysis at elevated pressures using a variable heating rate wire-mesh apparatus

Abstract

A high-pressure wire-mesh reactor has been developed with a heating rate range from 1 to 1000 K/s, and the capability of applying extended isothermal holding times (up to 200 s at 600 o C has been used). These improvements to the range of conditions that can be covered with this type of instrument have been achieved by the use of computerized feedback temperature control and the provision of water cooling for the internal electrode assembly. Experiments using samples of Linby and Pittsburgh No. 8 coals have shown that, as inert gas pressure is raised, the effect of increased heating rates, almost completely disappears. In high-pressure hydrogen slow heating (5 K/s) can even give higher total volatile yields than rapid (1000 K/s) heating with short holding times, though this was found possibly to be due to the greater time available for char hydrogasification during heating