摘要
不锈钢酸洗污泥是危险废弃物,但其中含有大量有价值重金属,因而如何对其资源化利用具有重要意义。研究不锈钢污泥在碳热还原反应过程中铁、铬、镍等元素在物相间的相互作用及转化,探究铁、铬、镍元素在污泥中分布的影响因素。利用XRD分析污泥在还原过程中的矿相变化,金相显微镜、SEM-EDS分析污泥还原过程中金属颗粒的形貌及其迁移行为。结果表明,在污泥升温碳还原的过程中,NiO与Fe_(2)O_(3)形成NiFe_(2)O_(4)尖晶相并被还原形成Ni-Fe金属相;FeO与Cr_(2)O_(3)形成FeCr_(2)O_(4)并与碳还原形成Fe-Cr-C金属固溶体;含碳的Ni-Fe-Cr-C等合金颗粒在高温下熔化并汇聚长大。当温度为1 300℃时,渣相内部结构软化形成微熔池,使得金属液滴具备更好的迁移长大条件,非金属元素形成了以[Si-O]为主要网络结构的熔渣球团,这些网络结构由Ca_(2)Al(AlSiO_(7))组成。
Stainless steel pickling sludge is a hazardous waste, but it contains a lot of valuable heavy metals, so it is of great significance how to resource utilization of stainless steel sludge. The interaction and transformation of iron, chromium, nickel and other elements in the process of carbothermal reduction reaction were studied, and the influencing factors of iron, chromium as well as nickel elements distribution in the sludge were explored. The phase of sludge and its reduction samples were analyzed by XRD, and metallographic microscope and SEM-EDS were used to analyze the morphology and migration behavior of metal particles in sludge reduction process. The results show that NiO combines with Fe_(2)O_(3) to form NiFe_(2)O_(4) spinel phase, which is reduced to form Ni-Fe metal phase during sludge carbon reduction process. FeO combines with Cr_(2)O_(3) to form FeCr_(2)O_(4), which forms Fe-Cr-C metal solid solution with carbon reduction. Ni-Fe-Cr-C alloy particles containing carbon are lower melting point which can transfer and grow up through convergence. There will form a micro molten pool as the reduction temperature is 1 300 ℃, which provides better migration and growth conditions for the metal droplets. The nonmetallic elements form slag pellets with [Si-O] network structure, which is composed of Ca_(2)Al(AlSiO_(7)).
作者
张继新
李秋菊
周仓
李重河
王丹
ZHANG Jixin;LI Qiuju;ZHOU Cang;LI Chonghe;WANG Dan(State Key Laboratory of Advanced Special Steel,Shanghai University,Shanghai 200444,China;Shanghai Key Laboratory of New Technology Development and Application of Iron and Steel Metallurgy,Shanghai University,Shanghai 200444,China;Materials Science and Engineering,Shanghai University,Shanghai 200444,China)
出处
《钢铁研究学报》
CAS
CSCD
北大核心
2021年第9期920-928,共9页
Journal of Iron and Steel Research
基金
国家自然科学基金资助项目(51974185,U1760109)
上海工程技术研究中心建设资助项目(19DZ2252900)。
关键词
不锈钢酸洗污泥
半熔态还原
微熔池
汇聚长大
stainless steel pickling sludge
semi-molten reduction
micro molten pool
gathering
