Increasing the temperature of direct reduction process offers many advantages such as higher production rate and improved product quality. The most important phenomenon which imposes an upper limit on the reduction temperature is sticking of the sponge iron in direct reduction reactor; so, practically the temperature cannot exceed a certain limit. Most major producers of sponge iron, are encountered with the problem of sticking of oxide pellets during reduction process. Previous investigations have indicated that coating of the pellets with an appropriate material prior to the reduction process leads to a considerable decrease in the sticking tendency of pellets. In this research, possibility of using waste materials such as electric arc furnace slag, converter sludge and ladle furnace slag for coating of oxide pellets have been investigated. Obtained results showed that these coatings significantly lower sticking of the pellets. The percentage of remained cluster after 5 revolution of tumbler drum for uncoated samples and samples coated with electric arc furnace slag, converter sludge, ladle furnace slag and hydrated lime were 28.7%, 6.24%, 11.56%, 3.64% and 5.2%, respectively. Furthermore, towards the end of the reduction process, coated pellets had better reducibility compared to uncoated pellets. The Final percentage of reduction for uncoated samples and samples coated with electric arc furnace slag, converter sludge, ladle furnace slag and hydrated lime were 90.29%, 94.14%, 92.2%, 94.63% and 93.15%, respectively. Furthermore, suspensions of ladle furnace slag and hydrated lime compared to electric arc furnace slag and converter sludge showed higher stability. Keywords: Oxide pellet, Direct reduction, Sticking, Coating
