永城矿区介石煤的煤岩组成及分选特性研究

发布时间：2018-07-06 11:46

本文选题：永城介石煤 + 煤岩组成　；参考：《中国矿业大学》2015年硕士论文

【摘要】：永城矿区的洗精煤具有低灰、低硫、高发热量的特点,大块的精煤可以作为直接气化的原料;细颗粒则用来发电,用作高炉喷吹。块精煤中夹杂着一种介石煤,造成精煤质量下降,其质量介于精煤和矸石之间,密度较接近精煤,其中次生矿物与煤混合较均匀,而且质地紧密,不容易被破碎,容易造成块精煤的灰熔点降低、同时伴有结渣现象,但发热量相对较高,具有较高的利用价值。因此需通过合理有效的手段对介石煤进行分选。煤是由多种显微组分组成的混合物,对介石煤与块精煤的成分进行分析时可以得出:介石煤中镜质组含量为76.95%,块精煤中镜质组含量为95.35%,二者相差较大。本文针对介石煤的性质,采用破碎解离的手段将介石煤破碎到不同粒度上限,通过煤样破碎试验研究煤和煤岩显微组分的破碎性能。重液浮沉试验可以分选出富镜质组的低密度煤样及惰质组相对富集的高密度煤样,结合显微煤岩组分分析研究表明:介石煤主要分布在1.5-1.6 g/cm3密度级,随着破碎粒度变小,解离粒度逐渐加深,镜质组含量从未破碎解离前的76.95%上升到破碎后的86.29%,惰质组分的含量则从17.70%降低到9.42%,惰质组含量降低明显,这说明外力的破碎解离使煤中的煤岩组分产生了解离,各显微组分间由紧密嵌布的状态逐渐解离成分散的单体状态,并在重液浮沉作用下实现富集。对破碎至0.5mm以下的介石煤样进行浮选试验和分步释放试验,探索在不同药剂制度条件下介石煤的最佳浮选条件以及在相同药剂制度条件下,浮选机与浮选柱浮选效果的比较。通过浮选可以实现镜质组分的相对富集,从介石煤的浮选探索试验看出:通过浮选从煤中可以分离富集部分有机显微组分,但是精煤产率不高,镜质组分富集程度较低。通过破碎解离、重液分离以及浮选的方法可以实现有机显微组分的相对富集。将介石煤从块精煤中分离出来并加以利用,提高资源利用效率,对提高精煤质量和增加煤矿经济效益具有非常重要的意义。
[Abstract]:The clean coal in Yongcheng mining area has the characteristics of low ash, low sulfur and high calorific value. The bulk coal can be used as raw material for direct gasification, while fine particles can be used for power generation and blast furnace injection. There is a kind of mesite coal mixed in the block clean coal, which causes the quality of the clean coal to decrease, its quality is between the clean coal and the gangue, the density is close to that of the clean coal, and the secondary mineral and coal are mixed more evenly, and the texture is close, so it is not easy to be broken. It is easy to cause ash melting point of block coal to decrease, accompanied by slagging phenomenon, but the calorific value is relatively high, so it has higher utilization value. Therefore, it is necessary to separate mesite coal by reasonable and effective means. Coal is a mixture composed of many macerals. It can be concluded that the vitrinite content in the mesite coal is 76.95, the vitrinite content in the block coal is 95.35, and the difference between them is great. In this paper, according to the properties of mesite coal, the breaking and dissociation method is used to crush the mesite coal to different upper limits of particle size, and the crushing properties of coal and coal rock macerals are studied by coal sample crushing test. The low-density coal samples with rich vitrinite and the high-density coal samples with relative enrichment in inertinite group can be separated by heavy liquid floatation test. The results of microscopic coal composition analysis show that mesite coal mainly distributes in the density order of 1.5-1.6 g/cm3, and decreases with the crushing granularity. The content of vitrinite increased from 76.95% before fragmentation to 86.29% after fragmentation, and the content of inertinite decreased from 17.70% to 9.42%, and the content of inertinite decreased obviously. This indicates that the break-up and dissociation of the external forces lead to the dissociation of the coal and rock components in the coal, and the microscopic components are gradually dissociated from the closely embedded state into the dispersed monomer state and enriched under the action of heavy liquid floatation. Flotation tests and stepwise release tests were carried out on mesite coal samples broken to 0.5mm. The optimum flotation conditions of mesite coal under different reagent systems and the comparison of flotation effect between flotation machine and flotation column under the same reagent system were explored. The relative enrichment of vitrinite components can be realized by flotation. From the flotation experiments of mesite coal, it can be seen that some organic macerals can be separated and enriched from coal by flotation, but the yield of clean coal is not high and the enrichment degree of vitrinite component is low. The relative enrichment of organic macerals can be realized by means of crushing and dissociation, heavy liquid separation and flotation. It is of great significance for improving the quality of clean coal and increasing the economic benefit of coal mine to separate and utilize the mesite coal from the block coal to improve the efficiency of resource utilization.
【学位授予单位】：中国矿业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TD94

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