Pre-reduction sintering process with flue gas recirculation for reduction alkalis harm and flue gas emission  

预还原烧结烟气循环工艺降低碱危害及烟气排放

作　　者：ZHONG Qiang JIANG Wen-zheng GAO Wei LI Qian YANG Yong-bin JIANG Tao 钟强;姜文政;高伟;李骞;杨永斌;姜涛(School of Minerals Processing and Bioengineering,Central South University,Changsha 410083,China)

机构地区：[1]School of Minerals Processing and Bioengineering,Central South University,Changsha 410083,China

出　　处：《Journal of Central South University》2025年第1期106-121,共16页中南大学学报(英文版)

基　　金：Project(52274290)supported by the National Natural Science Foundation of China;Project(72088101)supported by the Basic Science Center Project for National Natural Science Foundation of China。

摘　　要：A pre-reduction sintering process with flue gas recirculation(PSP_(fsg)-FGR)was developed to mitigate alkalis harm to the blast furnace and reduce the flue gas emission in the whole ironmaking process.The results indicated that the pre-reduction sintering process(PSP)can effectively remove 58.02%of K and 30.68%of Na from raw mixtures and improve yield and tumbler index to 74.40%and 68.69%,respectively.Moreover,PSP was conducive to reducing NO_(x) and SO_(2)emissions and simultaneously increasing CO content in flue gas.Circulating CO-containing flue gas to sintering bed effectively recycled CO and further improved K and Na removal ratio to 74.11%and 32.92%,respectively.Microstructural analysis revealed that the pre-reduced sinter mainly consisted of magnetite,wustite and a small quantity of metallic iron,and very few silicate glass phase was also formed.This process can simultaneously realize alkali metal elements removal as well as flue gas emission reduction from the integrated ironmaking process.为了减轻碱金属对高炉的危害和降低整个炼铁过程的烟气排放,研究了预还原烧结烟气循环工艺(PSPfsg-FGR)。结果表明,预还原烧结工艺(PSP)可有效脱除铁矿石中钾和钠,脱除率分别达到58.02%和30.68%。此外,PSP可提高烧结矿的成品率和转鼓强度,分别达到74.40%和68.69%。同时,PSP有利于降低烟气中NO_(x)和SO_(2)的排放以及提高CO含量。烧结烟气再循环可以有效利用烟气中的CO,进一步将K和Na的脱除率提高到74.11%和32.92%。微观结构分析表明,预还原烧结矿主要由磁铁矿、浮士体和少量金属铁组成,还形成了少量的硅酸盐玻璃相。PSPfsg-FGR可有效脱除烧结工艺中的碱金属元素,同时减少整个炼铁流程中烟气的排放。

关 键 词：iron ore sintering pre-reduction sintering flue gas recirculation alkali element removal flue gas emission 

分 类 号：TQ1[化学工程]