Reduction behavior of iron ore pellets with addition of plastics along with conventional reducing agents

Abstract

Direct reduction of iron is an important route of iron production in India and uses coal/coke as reducing agent. Growing environment concerns and higher cost of coal is driving steel industries to consider alternatives to coal based technologies to make the production economical. A common alternative is the use of natural gas but all countries do not have natural gas reserves and the core issue of prices is not addressed. One viable alternative is the use of wastes that produce carbon monoxide and hydrogen on combustion. One such fuel is waste plastics. Injection of waste plastics in blast furnace have been reported in literature and the current work extends the application to direct reduction process. In the study, iron ore pellets were reduced using a mixture of carbon based reducing agent and plastics in laboratory. The PET grade of plastics were used and the reduction behavior was studied a different PET concentration and reducing temperature. The results showed increased reduction rate of iron pellets but only till a certain extent of mixing. The paper also discusses the activation energies and possible mechanisms of reduction for the process.