(上海大學(xué) 上海市現(xiàn)代冶金與材料制備重點(diǎn)實(shí)驗(yàn)室，上海 200072)
摘 要: 利用大載荷熱重分析儀、質(zhì)譜儀、碳分析儀、SEM和XRD測(cè)定不同還原條件下鈦鐵礦(FeTiO3)氣基還原產(chǎn)物的質(zhì)量損失率、鈦和鎂元素分布、微觀結(jié)構(gòu)及物相組成，研究富氫氣體還原鈦鐵礦過(guò)程中各氣體組分間的耦合作用機(jī)制。結(jié)果表明：在氫氣還原過(guò)程中金屬鐵在顆粒外層聚集，并伴隨著鈦和鎂兩種元素的聚集形成致密層; 富氫氣體還原則不形成相應(yīng)的致密層，金屬鐵以細(xì)小顆粒狀較均勻地分布在顆粒內(nèi)部，鈦和鎂也較為均勻地分散在整個(gè)顆粒內(nèi)部。此外，富氫氣體中的CO能在金屬鐵的表面形成一定量的表面碳，并能將H2O分子重新還原為氫氣，從而提高了氫氣在還原過(guò)程中的利用率。
關(guān)鍵字: 鈦鐵礦；鎂；富氫氣體；直接還原；耦合反應(yīng)
（Shanghai Key Laboratory of Modern Metallurgy and Materials Processing, Shanghai University,
Shanghai 200072, China）
Abstract:Thermogravimetric analyzer, mass spectrometer, carbon analyzer, SEM and XRD were utilized to study the reduction product of ilmenite (FeTiO3). The mass loss, distribution of titanium and magnesium, micromorphology and phase transitions were investigated. The coupling reaction between different components of hydrogen-rich gas was also discussed. The results show that a dense layer forms inside ilmenite particle with the beneficiation of metal iron, titanium, and magnesium in the hydrogen reduction process. Unlike the hydrogen direct reduction, the dense layer can not form in the hydrogen-rich gaseous reduction. The metal iron in the form of granule type distributes evenly in the body of the particle, and titanium and magnesium also distribute in all particles. In addition, the CO in hydrogen-rich gas can be dissociated on the surface of metal iron which plays the role of catalyst. The surface carbon which is formed by the dissociation of CO can reduce H2O molecule again, so that the utilization of hydrogen can be elevated.
Key words: ilmenite; magnesium; hydrogen-rich gas; direct reduction; coupling reaction
