2016 Volume 56 Issue 9 Pages 1563-1569
Decreasing NOx emission in sintering process is a key issue in steel industry. NOx emission in sintering process is decreased by coke combustion under high temperature. It has been investigated that coating layer of CaO–Fe2O3 composition on coke surface (CF coating method) is effective for decreasing NOx. It has been considered that CaO–Fe2O3 coating layer promotes high temperature combustion and functions as catalyst for reduction of nitrogen oxide.
In this study, CaO coating of coke (Lime coating coke: LCC) has been studied as simple technology for decreasing NOx. As the results, LCC has been effective like a CF coating method and it has been understood that CF melt formation on coke surface is important for decreasing NOx. About coating CaO ratio, 10% was preferable. And decrease in mixing time of LCC with iron ores (Post-mixing) was also effective. By LCC post-mixing, 17.6% NOx decreased and sinter productivity increased.