文献类型：期刊文献

中文题名：铁元素对煤气化过程矿物转化和熔融特性影响的研究进展

英文题名：Research progress on the effect of iron on mineral transformation and melting characteristics during coal gasification

作者：沈中杰[1,2];董子铮[1,2];梁钦锋[1,2];许建良[1,2];郭晓镭[1,2];代正华[1,2,3];刘海峰[1,2]

机构：[1]华东理工大学国家能源煤气化技术研发中心,上海200237;[2]华东理工大学上海煤气化工程技术研究中心,上海200237;[3]新疆大学化工学院,新疆乌鲁木齐830046

年份：2023

卷号：29

期号：7

起止页码：95

中文期刊名：洁净煤技术

外文期刊名：Clean Coal Technology

收录：CSTPCD;;Scopus;北大核心:【北大核心2020】；CSCD:【CSCD2023_2024】；

基金：国家自然科学基金青年基金资助项目(21908063)。

语种：中文

中文关键词：煤气化;灰渣;铁元素;赋存;相变;黏温特性

外文关键词：coal gasification;ash and slag;iron;occurrence;phase transition;viscosity-temperature characteristics

摘要：铁是普遍存在于煤中的重要元素,其含量和价态等参数是影响煤气化灰渣理化特性(矿物转化和熔融、结晶、黏温和流变性等)的关键因素。气化炉用煤的种类和操作工况(气氛和温度)等变化影响铁的赋存形态,含铁的煤气化灰渣呈不同理化性质,其研究对指导气化炉的顺畅排渣具有重要意义。综述了近年来学者对铁元素在气化灰渣的赋存形态、铁对煤气化灰渣的熔融特性、降温过程结晶性和黏温特性等研究进展。铁主要以FeO、Fe_(2)O_(3)、FeS和FeS_(2)等形式存在于原煤中,在煤气化过程中转化为含铁的硅铝酸盐类物质,且受气体组分(CO/CO_(2)/O_(2)/H_(2))、化学组成和温度影响显著。因Fe^(3+)具有强极性,难以与其他矿物反应,在氧化性气氛下的灰渣熔融温度较高;而CO、H_(2)等气体具有较强的还原性,灰渣中的Fe_(2)O_(3)被还原为亚铁(Fe^(2+)),其熔融温度降低,但还原为金属Fe时,其具有高熔点特性,灰熔融温度升高。煤气化灰渣中铁元素对熔融液态渣在冷却降温过程的结晶性能产生影响,包括含Fe的晶体种类、结晶温度、析晶条件、晶体形貌和尺寸等。其中,Fe与Ca在硅铝酸盐网状结构中的作用受气氛、温度和化学组成影响显著,主要为Fe/Fe^(2+)/Fe^(3+)三者的转化与钙长石类矿物的相互作用,影响含铁晶体转化和铁单质析出。阐明了煤气化灰渣中铁元素对其黏温特性的影响机制,包括黏度和临界黏度温度,铁的不同价态和含量是黏度变化和熔体结构转变过程的重要参数。最后,总结了铁元素对煤气化灰渣理化性质的作用,展望复杂气氛下(H_(2)/CO/CO_(2))铁单质、离子态(Fe^(2+)/Fe^(3+))等对煤气化过程矿物转化、灰渣熔融和结晶等物理和化学综合作用是明晰煤气化灰渣中铁元素作用的关键,需建立合适的含铁煤气化灰渣性质预测体系,为工业气化炉运行提供指导。
Iron is an important element commonly found in coal minerals,and its occurrence parameters such as content and valence are the key factors affecting the physical and chemical properties of coal gasification ash,such as mineral transformation,melting,crystallization,viscosity,rheology,etc.The type of coal used in gasifier and the change of operating conditions(atmosphere and temperature)affect the occurrence form of Fe,and the coal gasification ash containing iron shows different physical and chemical properties,which is[LM]of great significance to guide the smooth slagging of gasifier.Research progress on the occurrence form of iron in gasification ash,melting properties of Fe on coal gasification ash,crystallinity and viscosity-temperature properties during cooling process were reviewed.Fe mainly exists in raw coal in the form of FeO,Fe_(2)2_(O) 3,FeS,and FeS_(2),and is converted into iron-containing aluminosilicates during coal gasification,which is significantly affected by gas compositions(CO/CO_(2)/O_(2)2/H 2),chemical compositions and temperature.Due to Fe 3+has a strong polarity,it is difficult to react with other minerals,and the melting temperature of ash slag in oxidizing atmosphere is higher.While CO,H_(2) and other reducing gases have strong reducibility,Fe_(2)O_(3) in ash slag is reduced to ferrous(Fe^(2+)),its melting temperature is reduced,but reduced to metallic iron(Fe),it has a high melting point characteristic,ash melting temperature increases.The effects of Fe in coal gasification ash on the crystallization properties of molten liquid slag during the cooling process include the types of Fe-containing crystals,crystallization temperature,crystallization conditions,crystal morphology and scale.Among them,the interaction of Fe and Ca in aluminosilicate network structure is significantly affected by atmosphere,temperature and chemical composition.The main effect is the interaction between the transformation of Fe/Fe^(2+)/Fe^(3+)and calcium feldspar minerals,which affects the transformation of iron-containing crystals and the precipitation of iron.The effect of Fe on the viscosity-temperature and viscosity-temperature characteristics of coal gasification slag was discussed,including the variation of viscosity and the critical viscosity temperature,the different valence states and contents of Fe were important parameters in the process of viscosity change and melt structure transformation.Finally,the effect of Fe on the physical and chemical properties of coal gasification ash was summarized.It is expected that the combined physical and chemical effects of iron elemental and ionic state(Fe 2+/Fe 3+)in complex atmosphere(H_(2)/CO/CO_(2))on mineral conversion,ash melting and crystallization are the key to clarify the role of iron in coal gasification ash.It is necessary to establish a suitable prediction system for the properties of iron coal gasification ash and slag to provide guidance for the operation of industrial gasifier.