微量硫黄含有CO-CO2混合ガスによるウスタイトペレットの還元に伴う体積膨脹
1985 年 71 巻 10 号 p. 1311-1318
詳細
1985 年 71 巻 10 号 p. 1311-1318
Swelling of wustite pellets during the reduction with CO-CO2 mixtures containing COS at low partial pressure was investigated in the temperature range from 800 to 1 000°C.
When the ratio PCOS/PCO in reducing gas was lower in 10-2 than the equilibrium ratio between iron and iron sulphide, the abnormal swelling of pellets was observed as accompanied with the formation of fibrous iron. This range of the gas ratio was seemed to be independent of the presence of CaO and K2O in wustite.
CaO and K2O dissolved in wustite did not directly induce the abnormal swelling, but the gaseous sulphur enhanced the abnormal swelling more greatly due to the coexistence of oxide additive in wustite.
Two reasons for the favorable formation of fibrous iron induced by the gaseous sulphur were based on the sulphur adsorption on the solids. One is that sulphur diminishes the number of sites for the iron nucleation due to its adsorption at defects on wustite surface. The other is that sulphur induces upward growth of iron, inhibiting lateral growth of iron due to its adsorption on active iron surface.
