Improvement in tungsten sponge production technology

With the aim of searching methods of direct reduction of tungsten oxide concentrates or thermodynamical study of the W-O-C system is accomplished. It is established that the following thermodynamic equilibria are of interest for practice: equilibria of WO2 formation reaction, equilibria of tungsten reduction with carbon, tungsten carbide and carbon monoxide. A two-stage process of manufacturing tungsten-bearing metallized concentrate is developed on the basis of study results. The first stage of reduction runs at 973-1223 K for 4-9 h. The second stage is carried out at 1273-1723 K during 2-6 h with subsequent cooling in a gas environment down to 273-303 K. The density of produced metallized briquets equals 3.2-3.67 g/cm3