Hydrogen-based direct reduction of industrial iron ore pellets:Statistically designed experiments and computational simulation  

作　　者：Patrícia Metolina Tiago Ramos Ribeiro Roberto Guardani 

机构地区：[1]Chemical Systems Engineering Center,Department of Chemical Engineering,University of São Paulo,São Paulo 05508-900,Brazil [2]Metallurgical Process Laboratory,Institute of Technological Research,São Paulo 05508-901,Brazil

出　　处：《International Journal of Minerals,Metallurgy and Materials》2022年第10期1908-1921,共14页矿物冶金与材料学报（英文版）

基　　金：Institute of Technological Research–IPT,Fundcao de AmparoàPesquisa do Estado de Sao Paulo;Brazil[Process 2019/05840-3];Conselho Nacional de Desenvolvimento Científico e Tecnológico;Brazil[Process 167470/2018-3]。

摘　　要：As part of efforts to reduce anthropogenic CO_(2) emissions by the steelmaking industry,this study investigated the direct reduction of industrially produced hematite pellets with H_(2) using the Doehlert experimental design to evaluate the effect of pellet diameter(10.5-16.5 mm),porosity(0.36-0.44),and temperature(600-1200℃).A strong interactive effect between temperature and pellet size was observed,indicating that these variables cannot be considered independently.The increase in temperature and decrease in pellet size considerably favor the reduction rate,while porosity did not show a relevant effect.The change in pellet size during the reduction was negligible,except at elevated temperatures due to crack formation.A considerable decrease in mechanical strength at high temperatures suggests a maximum process operating temperature of 900℃.Good predictive capacity was achieved using the modified grain model to simulate the three consecutive non-catalytic gas-solid reactions,considering different pellet sizes and porosities,changes during the reaction from 800 to 900℃.However,for other temperatures,different mechanisms of structural modifications must be considered in the modeling.These results represent significant contributions to the development of ore pellets for CO_(2)-free steelmaking technology.

关 键 词：hydrogen use non-catalytic gas-solid reaction grain model porous hematite pellet CO_(2)emissions reduction Doehlert experimental design 

分 类 号：TF046.6[冶金工程—冶金物理化学]