煤炭在我国的能源消费结构中占有至关主要的地位，新疆地区拥有丰富的煤炭资源储量，是我国重要的能源接续区和战略储备区。新疆地区的煤炭资源，特别是准东煤中碱金属和碱土金属(Alkali metals and Alkaline Earth Metals，AAEMs)含量普遍较高，属于典型高碱煤，可供长期使用。随着新疆地区煤炭资源的大规模开采和利用，高碱煤在燃烧过程中发生的结渣、沾污和腐蚀等问题严重限制了其大规模和高效利用。实现 100%纯烧高碱煤是高碱煤利用的重要目标，但解决纯烧过程中涉及的灰问题是首要问题。基于现代多元、分时、动态分方法，利用CiteSpace软件获取近 20a来高碱煤研究领域的 4401条文献，对文献结果进行文献聚类分析、关键词凸显分析和时间序列分析，对不同时期的研究热度峰值区间进行了系统分析。指出了该领域未来研究需要关注AAEMs的存在形式与迁移特性、低温共熔物形成机制、燃烧高效利用调控措施等方面。以典型高碱煤为基础，总结了其基本理化特性，重点剖析煤灰碱性组分对煤灰熔融温度的影响和AAEMs的存在形式。在此基础上，调研AAEMs和低温共熔物 2个核心方面研究进展，探究AAEMs迁移特性与低温共熔物的生成机制，对煤炭清洁高效利用低碳具有重要意义。然后，将高碱煤燃烧高效利用调控措施归纳为降低AAEMs含量、增加酸性组分和反应器运行与结构优化三大类别，分析了利用措施对缓解高碱煤结渣沾污的原理与效果，并指出对应方法的问题和不足。此外，提出煤粉纯化-燃烧高效利用技术或许是解决高碱煤燃烧高效利用难题的有效手段。最后，双碳背景下对火电提出了灵活性改造需求，火电机组需要提高变负荷调节能力，以保证稳定的功率输出。指出了实现高碱煤燃烧高效利用调控建议和未来研究方向，需要结合地方多样化资源优势并系统地制定整体方案，在全流程精准控制结渣、沾污和腐蚀等难题，实现清洁高效低碳利用。
Ash chemistry issues and efficient combustion research progress in pure coal combustion of high-alkali coal
Coal constitutes a pivotal element of China's energy consumption structure.Xinjiang,which boasts consider-able coal deposits,is a crucial energy succession zone and strategic reserve area within China.The coal resources in Xinji-ang,particularly the Zhundong variety,typically exhibit elevated concentrations of alkali metals and alkaline earth metals(AAEMs),which are typical high-alkali coal well-suited for prolonged utilisation.The large-scale mining and utilisation of coal resources in Xinjiang has resulted in significant challenges,particularly in the form of slagging,staining and corro-sion of high-alkali coal during combustion.These issues have severely limited the large-scale and efficient utilisation of this coal resource.The objective of achieving 100%clean combustion of high-alkali coal represents a significant chal-lenge in the field of high-alkali coal utilisation.However,the primary obstacle lies in the resolution of the ash issue inher-ent to the clean combustion process.In this paper,about 4401 literatures in the field of high-alkali coal research in the past 20 years were obtained by using CiteSpace software.These literatures were subjected to literature clustering analysis,keyword highlighting analysis and time-series analysis.In addition,the peak interval of the heat of research in different periods was systematically analysed.It is highlighted that the future research in this field should prioritise the investiga-tions into the existence form and migration characteristics of AAEMs,the low-temperature eutectic formation mechanism,and the development of combustion-efficient utilisation regulation measures.Based on a representative high-alkali coal,a summary of the fundamental physicochemical properties was presented,with a particular focus on the impact of the al-kaline component of coal ash on the melting temperature of coal ash and the existence form of AAEMs.This study invest-igates the research progress of two core aspects,namely,AAEMs and low-temperature eutectics,with the objective of ex-ploring the migration characteristics of AAEMs and the generation mechanism of low-temperature eutectics.This is of great significance for the clean and efficient utilisation of coal with low carbon.Subsequently,the regulatory measures for the efficient utilisation of high-alkali coal combustion are categorised into three principal groups:the reduction of AAEMs content,the increase of acidic components,and the optimisation of reactor operation and structure.The principles and ef-fects of the utilisation measures on the mitigation of slagging and staining of high-alkali coals are then analysed,and the shortcomings of the corresponding methods are identified.Furthermore,it is proposed that the coal dust purification-com-bustion efficient utilisation technology may prove an effective means of solving the problem of efficient utilisation of high-alkali coal combustion.Ultimately,the dual-carbon context underscores the necessity for thermal power units to enhance their variable load regulation capabilities,thereby ensuring a stable power output.This paper puts forward suggestions and proposes avenues for future research in order to achieve the efficient utilisation of high-alkali coal combustion.It is essen-tial that these are combined with local diversified resource advantages and that an overall plan is formulated in order to ac-curately control the problems of slagging,staining and corrosion throughout the entire process.This will enable the clean,efficient and low-carbon utilisation of the resource to be achieved.
high-alkali coalCiteSpaceslagging and foulingefficient combustion utilizationpurification-combustion
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维普
