燃料化学学报2016，Vol.44Issue(9)：1025-1033,9.
利用SiO2-Al2 O3-CaO-FeOx 四元体系评价煤中矿物质的热及流变特性研究
Evaluation of the thermal and rheological characteristics of minerals in coal using SiO2-Al2 O3-CaO-FeOx quaternary system
摘要
Abstract
In the present work, the synergistic effect of components on the mineral behavior in the SiO2-Al2 O3-CaO-FeOx quaternary system was tentatively evaluated. The mineral transformation and reaction were analyzed by thermo-mechanical analyzer ( TMA ) , differential scanning calorimetry ( DSC ) , X-ray diffraction ( XRD ) and thermodynamic calculation ( FactSage ) . In addition, the apparent viscosities of synthetic slags, expressed as a function of temperature and composition, were determined using a high temperature rotary viscometer with temperature ranging from 1 700℃ to re-solidifying temperature. The results demonstrated that the TMA and DSC approaches were applicable to characterize the mineral behavior under in-situ conditions. Silica and alumina preferred to be transformed to high temperature cristobalite and a-alumina with relatively stable structure and high viscosity, respectively. On the other hand, the reaction and transformation of silica and alumina could be accelerated by some valuable fluxing agents, particularly calcium oxide and iron oxides. The addition of ferrous oxide into synthetic slags could lower its viscosity compared with that of ferric oxide and ferroferric oxide. Furthermore, the reduction of iron oxides to metallic iron remarkably increased the viscosity. Ferric oxide may take part in the random glass network in a similar fashion with alumina. Besides, iron oxides with the oxidation state of Fe2+may also act as a modifier under slightly reducing conditions and higher temperatures. The sensitivity of viscosity of mineral matters to temperature excursion decreased with increasing calcium oxide content as calcium oxide was able to enhance the solution ability of iron oxides in the SiO2-Al2 O3-CaO-FeOx quaternary system.关键词
矿物质行为/黏度/热机械分析/四元体系/铁氧化物Key words
mineral behavior/viscosity/TMA/quaternary system/iron oxides分类
化学化工引用本文复制引用
王彩红,林雄超,杨萨莎,刘淑琴,YOON Seongho,王永刚..利用SiO2-Al2 O3-CaO-FeOx 四元体系评价煤中矿物质的热及流变特性研究[J].燃料化学学报,2016,44(9):1025-1033,9.基金项目
The project was supported by the National Natural Science Foundation of China (21406261).国家自然科学基金(21406261)资助 （21406261）
