Softening and melting performance of mixed burden under the simulated hydrogen-rich blast furnace atmosphere

ABSTRACT The effects of the application of iron coke in hydrogen-rich blast furnace atmosphere on the softening and melting performance of burden were studied.The results indicated that with the increase in hydrogen content, the cohesive zone of mixed burden became narrower and the permeability of charge was improved, and the suitable hydrogen content was 10vol.-%. The application of iron coke could promote the iron ore reduction and carburizing of iron, decrease the melting temperature by 1–10°C, decrease the dripping temperature by 5–16°C, narrow the cohesive zone, improve the air permeability with S value decrease of 3.19–13.87 kPa °C, and reduce the dissolution loss of coke and ensure the skeleton function of coke. The suitable burden structure was confirmed as follows, i.e. the ratio of pellets and sinter is 4:6, and the ratio of iron coke and coke is 2:8.