新疆炼焦煤因其独特的成煤地质条件和较晚的成煤地质年代，使得新疆中等挥发分炼焦煤具有较低的煤化度和较高的氧含量，导致全新疆炼焦煤所制焦炭具有较高的反应性(CRI)和较低的反应后强度(CSR)，尽管在新疆炼焦煤中配加高比例的内地中等挥发分炼焦煤能明显改善焦炭质量，但炼焦成本显著上升。为此，以4种新疆低质炼焦煤和2种内地优质炼焦煤以及自主研发的一种改质剂为原料，开展了单种煤以及配合煤的10 kg铁罐改质炼焦试验。结合显微光度计、扫描电镜、XRD试验探索了改质剂的添加对焦炭结构影响，并且通过改质剂与新疆煤的热重分析试验揭示了改质剂对焦炭强度的改质机制。实验结果表明:添加0.3%的改质剂与全新疆低质炼焦煤共炭化炼焦，所得焦炭的热态强度指标明显改善(CRI下降约14%，CSR提升约15%)，而且改质焦炭的综合性能指标能达到现有新疆焦化企业配入高比例的内地优质炼焦煤所制焦炭指标。改质剂能结合低质炼焦煤快速热解阶段形成的活性含氧片段，使得该阶段自由移动H与含氧片段的反应减少，进而自由移动H的消耗将减少，这将促使胶质体的数量和稳定性增加，导致焦炭的微晶层片尺寸增大、间距减少、堆砌高度增加，使得焦炭的微晶体积增大，各向异性程度增加，气孔率下降，致密度上升。

The formation of Xinjiang coking coals is characterized by unique geological conditions and relative late geological age,so that the medium volatile Xinjiang coking coals contain a relatively low degree of coalification and high oxygen content,resulting in the coke prepared from these coals with high reactivity of coke (CRI) and low strength after reaction (CSR).In order to improve the coke quality,adding a high proportion of inland medium volatile coking coals to Xinjiang coking coals is an effective method to manufacture metallurgical coke,but the coking costs will increase significantly.Therefore,four low quality coking coals from Xinjiang have been carbonized singly,in coal blends with two high quality coking coals from inland or self developed modifier in a 10 kg iron pot,which was buried in an industrial coke oven.To investigate the influence of modifier on coke structure,modified coke and raw coke were investigated by using Micro photometer,SEM,and XRD techniques.The modification mechanisms were also analyzed by the pyrolysis experiment of medium volatile Xinjiang coking coal and modifier using TG analyzer.The results showed that the CRI value of modified coke decreased by about 14% while the CSR value increased by about 15% when coal blends obtained from four Xinjiang coking coals were carbonized with 0.3% modifier.Besides,the comprehensive performance indexes of modified coke could match that of common coke that was prepared from the high proportion of inland coking coals and Xinjiang coking coals.The modifier could combine the active oxygen containing fragments so that the reactions of transferable hydrogen and active oxygen containing fragments were going to be decreased,which were responsible for the lower consumption of transferable hydrogen in the fast pyrolysis stage of coal.Therefore,more amount of stable mesophase could be observed in modified coal,which contributed not only to reduce the spacing of microcrystalline layers and the porosity but also to increase the size and stacking height of the microcrystalline layers,volume of microcrystalline,the degree of anisotropy,and the consistency of surface in subsequent coke.

1 实验

   1.1 实验原料

   1.2 实验装置及方法

2 结果和讨论

   2.1 煤质分析

   2.2 焦炭质量分析

   2.3 焦炭孔隙度及微观结构分析

   2.4 焦炭微晶结构参数分析

   2.5 煤样热重分析

3 结论