Effect of catalyst on tail gas during reduction of vanadium-titanium magnetite carbon-containing pellet

Abstract

Catalyst can enhance the reduction effect and promote the reduction of vanadium titanomagnetite. In this paper, the carbon-containing pellets of vanadium titanomagnetite were prepared by using highly volatile coal as the reducing agent under the background of a novel process of pre-reduction in the rotary kiln. The effects of CaO, CaCO3, B2O3 and borax (Na2B4O7·10H2O) on the tail gas characteristics of carbon-containing pellets in the prereduction process were studied by using a simulated rotary kiln and flue gas analyzer. The results showed that the enhanced reduction effect of boron catalysts was slightly stronger than that of calcium catalysts, among which CaO catalyzed the least and borax the best. With the increase of metallization rate, the CO utilization in the tail gas is generally reduced, while when using CaCO3 as the catalyst, the CO utilization is significantly increased. Due to different reduction mechanism, the boron catalysts have little effect on the tail gas, and the calcium catalysts have a great effect on the tail gas. Based on the experimental results and the characteristics of the tail gas from the reduction process, we put forward the idea of using CaCO3 as the best catalyst and using CaO to absorb CO2 in the tail gas to form CaCO3.