| The anthracite and lean coal, which belong to the high rank coal, make up a greatpart of the non-coking coal. However, these two kinds of non-coking coal have not beenused for coke making, because they do not have caking properties. Therefore, bymodifying treatment anthracite and lean coal for coal blending for coking, it can helpdecrease the cost of production, improve economic efficiency of enterprises, and help tosolve the problem of coking coal resource scarcity.This subject study using a pulverized coal modifier(ZBS), which is independentresearch and development modifier, modified the coking property of anthracite and leancoal, and to improve the add quantity of non-coking coal in coking process. Meanwhile,based on the plastic mechanism of coking and the principle of hydrogen supply, themodification mechanism of ZBS has been studied through the elemental analysisdetection method. In the200kg coke oven experiment, both the top-charging methodcoking and the stamp-charging coking, discussed the effect of ZBS on improve thequality of coke when blended with anthracite and lean coal. The4.3m coke ovenindustrial test have achieved with an amount of more than10wt.%non-coking coal wasadded, and the quality of coke is up to standard. Through experimental study, mainconclusions are shown as follows:①Studied the mechanism of ZBS modified the anthracite and lean coal. First,anthracite and lean coal after adding ZBS, its ash and sulfur are not adverselyaffected;Second,ZBS modifier can supply hydrogen to the radical fragment which aregenerated from coal pyrolysis, and make the fragment reach saturation and stabilized toproduce liquid component which has low relative molecular mass. As thus, the increaseof metaplast content in coking process, contribute to the bond of inert components andadd quantity of non-coking coal in coking process.Finally, ZBS modifier plays a role ofcatalytic agent in the coal pyrolysis. That is to say, ZBS can catalyze the coal pyrolysisreaction, which is conducive to produce more metaplast and improve the bondingsituation of non-coking coal,after the modification of non-coking coal has a certainplasticity temperature range, coking performance is improved.②As the result of the200kg coke oven Conventional coketest, when blended coaladded5wt.%anthracite and6wt.%lean coal in the top-charging method coking, theoptimal amounts of ZBS–M03modifier for0.10wt.%of mixed coal which moisture content of10wt.%. The coke quality of the optimal treatment group, compared with theblank group which without non-coking coal, has been significantly improved. Thecrushing strength of coke (M40) increased by0.8%, post-reaction strength of coke (CSR)increased by3.30%.③As the result of the200kg coke oven Tamping coketest, when blended with25wt.%non-coking coal in the stamp-charging coking, the optimal amounts of ZBSmodifier for0.20wt.%, and the quality of coke reached the standard of second classmetallurgical coke.④Based on the200kg coke oven test research, put forward the industrial testscheme suitable for Kunming Iron&Steel Co, Ltd.Ratio0: Yipinglang coal10wt.%,Panjiangcoal20wt.%, coking coal55wt.%,1/3coking coal15wt.%; ratio1and ratio2Add ZBS-M03modifier, ratio3add ZBS-M05modifier, using the most good amount,are blended with5wt.%anthracite and6wt.%lean coal.⑤The results of industrial test shown that: Compared with the blank group (ratio0),the metallurgical properties of coke from other groups (ratio1, ratio2and ratio3) haveimproved. In ratio1, the M40raised by1.45%, wear strength of coke (M10)reduced by1.9%, coke reactivity (CRI) fell by5.37%, and CSR raised by7.04%. In ratio2, the M40raised by1.75%, M10reduced by1.8%, CRI fell by1.95%, and CSR raised by1.18%. Inratio3, the M40raised by3.10%, M10reduced by1.2%, CRI fell by0.10%, and CSRraised by0.71%. Through analyzing the economic benefit for each ratio, it is concludedthat the optimal proportion is ratio1, by which can reduce the cost of coal blendingabout24.4Yuan/ton. |
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