| Coking is the longest and most successful technology in all coal utility technologies. But due to the complexity, diversity and inhomogeneity of coal structure and constitute, up to now, practice and experience keep ahead of theory in coke-making industry. Studying coking process further from theory is the aim of this subject. According to this goal, the work in three aspects were done in this paper:1) 16 coals of different rank were chosen, and coking experiments were done at 3 ℃/min in a IKg experimental coke oven. The chars and cokes produced at different final temperature were testes and analyzed by different methods and measures after cooled to room temperature, in order to get the detailed coking mechanism of different rank coals from these results.2) Two different anthracites and weak-caking coals were chosen and blended with a fat coal and a coal tar pitch (CTP) and a petroleum pitch (PP) respectively in different ratios for coke making to learn further the co-carbonization process of non-coking coals.3) A non-recovery coke oven, SJ96 coke oven, is chosen and studied. From measuring the top space gases constitutes and numerical calculating the temperature field distribution during coking process, the coking technology and characteristic was got basically. From above experimental work, the results are as follows: Each denotation method of coal rank has its localization. The volatiles of 16 coals have quadric multinomial relations with their dilatation temperature TI and theirvitrinite maximum reflection R0 v,max respectively. Equation were as follows: The coal with 35% or so volatile has the largest dilatation and plastic temperaturedomain in all 16 different rank coals .During coking process, the optical textures of coal with volatile <20% becomeunchanged up to temperature higher than 600 ℃, and most are domains and flows;while those with volatile >20% become unchanged at temperature >500℃, mostof them are mosaics.It can be watched by SEM that the conglutinating of fat coal during cokingprocess, but weak-caking coal shows granule fragments, and lean coals showslight variation. Chars produced by different rank coals can be saw that wasconstructed by layers of 40~100nm.During coking process, the true relative density (TRD) of coals with volatile<20% have a inflexion at 600 ℃, if temperature is >600℃, TRD increases morerapidly; while those with volatile >20% have a inflexion at 500℃, TRD increasesmore rapidly if >500℃. Except for gas coals and weak-caking coals, duringcoking process, it has linear relation between volatile variation of other coals andtheir TRD. As the volatiles drop down, their effects on TRD go up.The coke TRD decreases approximately linearly as volatile increases. The cokeproduced by weak-caking coals has the lowest TRD in 16 coals.The cokes produced by anthracites and weak-caking coals have highmicro-strength in all 16 cokes, other cokes micro-strength dropped slightly asvolatile increases. As the heating rate increases, micro-strength declines.The relation between coke micro-strength and coal volatile and petrography canbe deduced as follows:M=87.35 - 0.45Vdaf- 3.821, r=0.6581During coking process, the diameter of fragment micro-crystal layers of all coals (La) increases linearly as temperature increases, the distance between layers (d) don't show much change, it has not rule of the variation of micro-crystal height (La). The coke produced by weak-caking coals has the largest layer distance (d) and least Lj.No evident relation between coke micro-strength and TRD is found. The coke rank order of approaching to graphic carbon: C1 >B 1 > A1 > Y1 >D 1. From the extracting experiments of coals in CSa-NMP, it can be deduced that the extracting yield is up to coal rank, the coal with Vdaf 35% has the highest extracting yield (43%), and the coal with Vdaf<12% can hardly extracted any components.The extractable matters in coal are important components during c...
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