基于硫赋存形态及其热变迁行为的高硫煤脱硫机理研究

The rapid econmic development in China depends primarily on the consumption of coal resource. This present situation has caused the tension to supply the high quality coal. It is an effective way for the protection of the reasouce security and the reducing emission of the pollutants to reasonably and effectively utilize the abundant low grade coal with high-sulfur content. In view of this, we will carry out the basic research of removing sulfur from the coal with high-sulfur content based on the accurate characterization of the sulfur forms in coal, the pre-removal behavior of each form sulfur and their transformation in the thermal conversion process. The typical high-sulfur coals with different features will be selected as the research objects. The confirmation of the structure and content of each sulfur form, the investigation of their pre-removal behaviors, the intrinsic transformation performances and the influencing mechanisms of secondary reactions during the thermal conversion of coal are the the focal point in this project. The efficient removal of sulfur and its directional regulation and control based on the features and target uses of the high-sulfur coal are the research aims. So, we will establish the suitable method for the characterization of sulfur forms in coal and char, optimize the operation conditions of pre-removal sulfur from coal, and design the novel fixed bed reactor and in situ characterization system. The breakage of various types of chemical bonds related to the sulfur in coal during the removal and thermal conversion and their transformation are examined. And then, the influences of the secondary reactions on the transmission of sulfur during coal thermal conversion are discussed. The research results of this project will supply the theoretical basis and practical guidance for the establishment of the basic theory of removing sulfur from the high-sulfur coal and the implementation of its reasonable classification conversion technology.

我国经济快速发展严重依赖于煤炭资源的现状，已造成优质煤供应紧张的态势，合理有效地利用储量相对丰富的高硫煤是保障资源安全和污染物减排的有效途径，为此本申报项目拟进行煤中硫赋存形态的确切表征、各形态硫的预脱除行为以及其在热转化过程中的变迁为基础的高硫煤脱硫研究。以我国典型的不同组成特性的高硫煤为研究对象，以煤中各形态硫结构和含量的确定、预脱除行为的考察和其在热转化过程中的本征转化及二次反应的作用机理的探讨为研究重点，优选形态硫表征分析技术、优化煤中硫的预脱除方法、构建新型固定床反应装置和原位表征系统，以实现与煤中硫相关的各化学键在硫的脱除及热转化过程中断裂和硫化物变迁的本征特性的考察、煤热转化时二次反应对硫变迁作用机理的探讨，达到基于煤质特性及其目标用途的高硫煤中硫的有效脱除和定向转化调控的目的。研究结果可为高硫煤脱硫基础理论的建立和其合理分级转化技术的实施，提供理论依据和实际指。

基于我国经济快速发展严重依赖于煤炭资源造成优质煤供应紧张和环境污染不断加重的态势，提出合理有效地利用储量相对丰富的高硫煤资源，探索保障我国经济发展中的资源安全和污染物减排有效途径而进行的本课题研究工作，对不同种类、不同含量高硫煤中硫赋存形态表征和判定、形态硫热变迁行为及相互转化、煤种特性对热解过程中硫变迁行为影响、煤热解过程中硫变迁行为过程解析、煤热解过程中含硫气体释放机理、煤热解过程中硫变迁行为调控等方面的基础理论做了较为深入的分析探讨。以我国典型的组成特性不同的高硫煤为研究对象，优选可能的有机含硫模型化合物，利用加拿大光源Soft X-ray Microcharacterization Beamline建立了30种以上不同形态硫模型化合物的X射线吸收光谱谱库，借助X-射线吸收光谱与传统程序升温热解相结合的方式实现了煤中形态硫的准确判定，首次将煤中硫划分到12种以上；通过不同煤阶（横向）和不同热解温度（纵向）相结合的方式考察原煤热解过程中形态硫的变迁和相互转化，揭示了各形态硫之间的内部转化规律，发现高硫煤中各形态硫热变迁的600oC温度转折点；利用煤种特性差异，考察不同岩相组成、矿物质组成等因素对硫变迁行为的影响，得到了不同煤种中硫变迁行为的差异与煤种间的关联；构建了可测定煤热解生成的挥发分间、挥发分与半焦间相互作用的新型三管两段固定床反应装置和原位表征系统，揭示了挥发分与新生焦二次反应对硫变迁行为的显著影响；通过单种煤、配煤热解及单元热解实验中的主体产物及含硫成分分析，获得了煤中硫的产物分布及其与煤热解常规气体释放行为间的关联；基于H2S和NH3生成需要结合氢的过程分析，依据硫、氮模型化合物热解反应机理，阐述了煤受热时H2S和NH3形成和释放过程中存在的相互影响。基于煤主体热分解的同时存在挥发分与煤焦及其挥发分的相互作用，提出高有机硫焦煤和高挥发分低硫烟煤共热解调变硫变迁的途径。研究结果可为高硫煤合理分级分质转化技术的实施提供理论依据和基础指导。项目实施过程中，已培养博士研究生1名、硕士研究生6名，在培养博士研究生1名、硕士研究生3名；研究结果申报并授权国家发明专利2项，发表期刊论文13篇、会议论文12篇，其中SCI和EI收录23篇次。