Preparation of High-Strength Gasified Coke Used for DRI from Low Rank Coal

Abstract

This paper describes attempts to produce high-strength gasified coke for the production of direct reduced iron (DRI) from low rank coal. The method involves combining modified lignite with original low rank bituminous coal, briquetting and then carbonizing. The effects of content of modified coal and carbonization temperature on the qualities of coke were investigated. The results showed that the change of carbonization yield and density of coke was not obvious with the variety of modified coal content from 0 to 20%. The compressive strength of coke ascended with the increase of proportion of the modified coal. The yield of carbonization decreased gradually with temperature increased from 350 °C to 850 °C, and the compressive strength and density of coke showed a trend of decreasing firstly and then increasing. The resulting carbonized briquettes had a compressive strength as high as 2.05 ~ 9.10 MPa and density of 0.87 ~ 0.96 g/cm³. The process of preparated gasified coke from low rank coal, its not only realized the low rank coal clean efficient utilization, but also had a significant economic benefit from Heat - Electricity and Metallurgy coproduction.