Direct ore reduction with reduced gas reheater metal dusting problem

摘要

In a process for ore reduction with CO- and H2-containing gases formed by incomplete combustion of hydrocarbons, the reduction process off-gases are cooled, freed from H2O and CO2 and then mixed with fresh gas after preheating, the combustion temperature and the fresh gas/recycled gas ratio being chosen so that preheating temperature does not cause damage of the gas reheater by metal dusting. Preferably, incomplete combustion is carried out at 800-2000 (preferably 1000-1400) deg C and 2-30 (preferably 3-5) bars absolute pressure.