気孔率の異なるウスタイトペレットの硫化水素含有水素ガスによる高温還元挙動
1985 年 71 巻 6 号 p. 672-679
詳細
1985 年 71 巻 6 号 p. 672-679
In order to understand the effect of sulphur in reducing gas on the reduction behavior of iron oxides, the reduction experiments were conducted in H2-H2S mixtures with various sulphur activities at 1 000 and 1 200°C.
Macroscopic reduction patterns of pure wustite pellets can be divided into seven types, depending on the porosity of pellets and the activity of sulphur in the gas. This classification is slightly modified by the addition of MgO and CaO.
The reduction of pellets with low porosity is retarded greatly due to the formation of iron-oxysulphide liquid. The retardation of reduction does not occur with pellets of high porosity even under the high sulphur activity to form FeS. However, the reduction is retarded provided that the sufficient amount of the liquid to fill up the pores is formed.
The activity of sulphur in equilibrium under iron, wustite and iron-oxysulphide liquid was determined experimentally. MgO in wustite raises the sulphur activity and CaO lowers it.
Sulphur in the gas without the formation of sulphides causes the topochemical reduction pattern, independently of the presence of foreign oxides.
