Abstract
A severe control of carbon content is needed for the direct production of WC from WO3. In order to solve this problem for an industrial scale, a rotary carburization furnace for high temperatures was developed. This furnace comprises a rod-shaped heater of graphite in the center of the furnace and a rotating cylinder of graphite positioned coaxially around this heater. The inner wall of rotating cylinder is heated indirectly by means of supplying electric power to the graphite heater.
The mixed powder of WO3 and carbon was granulated and the resulting granules were continuously fed into the furnace which was kept at 1150°C-1650°C.
WO3 was sufficiently reduced and carburized by carbon in this furnace. The gases formed during reaction in the rotary furnace were CO and CO2, and the ratio PCO2/PCO corresponded to the carbon content of the carburized product.
It became clear from these results that the carbon content can be controlled by the ratio PCO2/PCO which is subject to the operating conditions of the rotary furnace.
