添加贫煤对配合煤成焦过程及焦炭性能的影响机制

Influence mechanism of meagre coal addition on coking process and coke performance of blending coal

在配煤炼焦过程中增加高硫肥煤及弱黏结性煤的配比,可有效保护稀缺优质炼焦煤以及作为扩展炼焦煤资源范围的有效手段。为探究不同高硫肥煤与高煤阶弱黏煤的配煤成焦能力,通过不同比例肥煤与贫煤的配合,采用坩埚焦进行焦炭质量评价,分析不同配比所得焦炭的粒焦反应性和反应后强度,并对焦样进行化学结构及孔结构分析,深度探究高硫肥煤与贫煤炭化后所得焦样的质量及其性能影响机制,以期为工业配煤方案中尽可能地利用高硫肥煤与贫煤提供理论基础。首先对2种高硫肥煤(FM1、FM2)与1种贫煤(PM)进行化学结构及热解特性分析,根据黏结指数确定肥煤与贫煤的配比程度;再针对不同配比煤样分别进行实验室坩埚焦炭化实验,并对所得焦样进行冷、热态性能及化学结构和孔结构分析。结果表明:随着高硫肥煤中配入贫煤比例的增加,其焦产率呈现上升趋势;FM1∶PM的质量比为6∶4时,粒焦反应性相对于单种肥煤焦改善较多,粒焦反应性、反应后强度分别相应提高了10.49%、8.98%;对于FM2肥煤,随着贫煤的配比增加,反应性变化不明显,但FM2焦样本身的反应性较低,在4∶6时粒焦反应性及反应后强度也相对较好。FM1、FM2与PM的质量比分别在6∶4、4∶6时的2个配煤焦样,其大芳香环结构比例相对较高、孔隙率低、焦炭质量较高。

Increasing the ratio of high-sulfur fat coal and weak bonding coal in the coking process can effectively protect scarce and high-quality coking coal and serve as effective means to expand the scope of coking coal resources.To explore different high-sulfur coal and coal rank weak adhesion of coal blending coking ability,through the different proportion of fat coal and meagre coal,the crucible coke quality were used to evaluate the coke quality.The reactivity and post reaction strength of coke particles with different ratios were analyzed.The chemical structure and pore structure of the coke samples were analyzed,and the quality and its performance impact mechanism of the coke samples obtained after the coking of high-sulfur fat coal and meagre coal was deeply explored,in order to provide a theoretical basis for the use of high-sulfur fat coal and meagre coal as much as possible in the industrial coal blending scheme.Firstly,the chemical structure and pyrolysis characteristics of two kinds of high-sulfur fat coal(FM1,FM2)and one meagre coal(PM)were analyzed,and the ratio of fat coal and meagre coal was determined according to the Bond index.Then,crucible coking experiments were carried out for coal samples with different proportions respectively,and the cold and hot properties,chemical structures and pore structures of the obtained coke samples were analyzed.The results show that the coke yield increases with the increase of the proportion of meagre coal in high sulfur fat coal.When the ratio of FM1∶PM is 6∶4,the coke reactivity is improved more than that of single fat coal coke,and the particle reactivity index and strength after reaction are increased by 10.49%and 8.98%respectively.For FM2 fat coal,the reactivity change is not obvious with the increase of the proportion of meagre coal,but the reactivity of FM2 coke sample itself is low,and the coke reactivity and strength after reaction are relatively good at 4∶6.FM1,FM2 and PM are respectively in the ratio of 6∶4,4∶6 of two coal mixing coke samples,the proportion of large aromatic ring structure is relatively high,the porosity rate is low,the coke quality is higher.