| 摘要 |
In production of sponge iron through continual reduction of iron oxides in a shaft furnace, where reduction gas is driven counter stream to the iron oxides, reduction gas is produced from re-circulation gas and with the help of a plasma generator of fixed reduction material produced injection gas. Re-circulation gas is released first mainly from CO2 and H2O, whereby the purified gas in the form of a primary substream is driven into plasma generator situated in the bottom part of a generation shaft filled with fixed reduction material, such as coke or the like. Water and/or oxygen is injected into the hot gas stream exiting the plasma generator so that the water and/or oxygen is made to react with the reduction material to form a mixture primarily of CO + H2 and so that the temperature level of the forming gas is kept within such a range that a slag is formed from the ash components in the fixed reduction material. The hot CO-H2 mixture exiting the upper part of the shaft is blended with at least one other substream of the purified re-circulation gas in such proportions that the resultant gas mixture temperature is appropriate for the reduction process.<IMAGE> |
