炼焦工艺条件对焦炭强度的影响分析

探讨了备煤、炼焦工艺和参数对焦炭强度的影响,从装煤堆密度、装煤粒度、结焦速率、炭化室宽度、熄焦方式5个方面进行了分析,结果表明,增加装煤堆密度和采用干法熄焦是改善焦炭强度的有效途径。     

装煤堆密度和细度对焦炭质量的影响研究

根据40 kg试验焦炉炼焦结果,探讨配合煤堆密度和细度对焦炭质量的影响。试验结果表明,随着配合煤细度的降低,堆密度增加,焦炭的机械强度和反应后强度有所改善,但反应后强度提高到一定程度不会再发生变化。     

炼焦工艺条件对焦炭反应性和反应后强度的影响

通过40 kg焦炉炼焦实验,研究了加热速率、焦饼终温、焖炉时间、入炉煤堆密度及入炉煤细度等对焦炭的CRI(焦炭反应性)、CSR(反应后强度)的影响。结果表明:为保证焦炭成熟和获得较低的CRI值,较高的CSR值,焦饼终温应控制在1000～1050℃范围内。炼焦时焖炉时间应控制在3 h以上。提高入炉煤堆密度,可显著改善焦炭的热性质。入炉煤细度控制在90%左右时,CRI、CSR值较佳。提高加热速率,特别是粘结阶段的升温速率,有利于改善焦炭的热性质。     

影响捣固焦块度的研究

采用40kg试验焦炉对影响焦炭块度的煤质和主要工艺参数进行试验研究。研究表明，单种煤和配合煤所得焦炭块度关联性指标主要有煤的挥发分、收缩度指标和对应焦炭抗碎强度M40。降低配合煤挥发分和收缩度有利于提高焦炭块度，M40与焦炭平均块度相关性较高。提高装煤堆密度会显著降低焦炭块度，堆密度高是导致捣固焦块度比顶装焦小的主要原因之一。炼焦加热制度对焦炭块度也有较大影响，其中单纯延长结焦后期焖炉时间对焦炭平均块度有反作用，只有真正减缓炼焦速率才可提升焦炭平均块度。     

配合煤粉碎细度对焦炭质量、产量的影响

研究了配合煤细度对配合煤堆密度、焦炭机械强度、热强度及焦炭产量的影响,用来指导实际生产;在一定条件下,按照实际使用的配比,进行不同细度下配合煤40kg小焦炉结焦性试验,寻找配合煤细度与焦炭质量、产量的对应关系。     

单种煤细度对焦炭热强度的影响

通过对单种煤细度进行预处理,利用70kg焦炉及配套干熄炉进行试验,在保证焦炭热强度的前提下,确定了预粉碎的煤种及最佳细度范围,研究表明,随着细度的增加,不同细度的瘦煤和气煤对焦炭热强度的影响不同,控制出料细度在60%左右时,配合煤堆密度增大,有利于提高焦炭产量及质量。     

配入低阶煤炼焦对焦炭性能影响的研究

选用焦煤、1/3焦煤、肥煤、瘦煤、长焰煤进行配煤,堆密度为0.7g/cm3和1.0g/cm3,采用2kg焦炉炼焦,对焦炭的冷态强度和热态性能分析检测,探讨了堆密度及低阶煤加入量对焦炭性能的影响,结果表明,配入低阶煤后,焦炭的冷态强度及热态性能变差,配比小于5%时,影响较小,适当提高原料煤堆密度,焦炭的冷态强度及热态性能得到改善。     

捣固炼焦对焦炭质量的影响

利用40kg试验焦炉进行顶装与捣固炼焦试验,对比分析发现,捣固炼焦工艺可以明显改善焦炭的冷态强度,提高焦炭抗碎强度,改善耐磨强度,还可提高焦炭的反应后强度,但对焦炭的反应性影响不大,可以使焦炭粒度组成更加均匀化。     

捣固炼焦对焦炭冷、热态强度的影响

在我国炼焦生产的主焦煤中,强粘结性的肥煤和焦煤所占比例较小,如何在炼焦过程中提高气煤的配比是焦化行业目前面临的一个重要课题。为此,济钢焦化厂利用20kg试验焦炉和热态试验装置对捣固炼焦生产的焦炭进行了冷、热态强度的研究。为了解捣固炼焦对焦炭冷、热态强度的影响,我们在现有配比的情况下,通过捣固使人炉煤堆密度分别提高10％、20％、30％;然后,再通过提高气煤的配比进行捣固试验,从而研究了焦炭冷、热态强度的变化。     

捣固焦与顶装焦在高炉内行为的对比分析

从密度、气孔率、反应性和微观结构等方面对捣固焦和顶装焦进行对比分析可知,捣固焦具有较高的显密度和显气孔率;碱金属对焦炭溶损反应起催化作用,碱金属对捣固焦的催化作用大于顶装焦。     

不同配煤比和堆密度对焦炭界面结合强度影响的实验研究

采用4种常规炼焦煤,在不同配比及堆密度下进行配煤炼焦实验,利用不同测试手段,对所得焦炭界面结合强度进行研究。实验结果表明:配煤炼焦过程中,当堆密度不变时,随着配煤中黏结性组分含量的提高,焦炭界面结合强度有增加的趋势;当肥煤和焦煤分别与瘦煤和气煤配合炼焦配比不变时,随着堆密度的提高,焦炭界面结合强度有增加的趋势;当堆密度为0.95 g/cm3、焦煤与气煤按4:6配煤炼焦时,所得焦炭界面结合强度BSSI达到最高值76.36%。     

影响焦炭质量的因素分析

焦炭的质量主要取决于配合煤性质和工艺条件。配合煤的性质主要是结焦性、煤的粘结性对焦炭强度的影响较大;炼焦煤的性质影响焦炭的灰分、硫分等化学组成,影响焦炭强度。炼焦的工艺条件是水分、灰分、细度、堆密度等;结焦时间影响焦炭冷态、热态性能和显微特性。     

Correspondence between the composition and plastic properties of British coals and the structural properties and reactivity of the corresponding cokes

The chemical composition and the physico-chemical properties of a suite of British coals, mainly of types 501/2 as defined by the NCB classification, but including some coals of higher and lower rank (NCB classification 204,401/2 and 601/2), were comprehensively investigated. Each coal was subsequently carbonized under controlled conditions of size distribution, bulk density and temperature on the 250 kg scale and the tensile strength, coke structure and coke reactivity were determined. This data highlighted the significance of the atomic ratio of the oxygen and carbon of the coals and the lack of relations between coal properties and coke structure and strength. As regards coke reactivity only complex relations with coal properties could be found, with coal rank, the oxygen/carbon ratio and the chlorine content being of greatest importance.     

Basic study on separate charge of coal and waste plastics in coke oven chamber

Nippon Steel Corporation started to operate a waste plastic recycling process using coke ovens at Nagoya and Kimitsu Works in 2000 and at Yawata and Muroran Works in 2002. Now the total capacity is 120,000 tons per year and the recycling process is operating smoothly. In this process, coals and added plastics are carbonized and changed into coke, tar, oil and coke oven gas in a coke oven chamber. At present, upper limit of the addition rate of waste plastics to blended coals is 1% so that the plastic addition does not affect coke strength. However, the amount of waste plastics in Japan is as much as about 10 million tons per year and there is a real need for increasing the amount of waste plastics treated by the waste plastic recycling process using coke ovens. We investigated a method of increasing the addition rate of waste plastics without affecting coke strength by charging coal and plastic separately in a coke oven chamber. In the case of the same plastic addition rate, charging the plastic in the bottom or the top part of the coke oven chamber can decrease the deterioration of coke strength compared with charging a homogeneous mixture of coal and plastic. Charging the plastic in the bottom decreases the coke strength to a greater extent than charging the plastic in the top. This is because the decomposition of the plastic charged in the bottom decreases the bulk density of the upper coal layer. The results suggest that charging the coal and waste plastics separately increases the amount of waste plastics treated in the waste plastic recycling process using coke ovens. In order to commercialize this method, further studies are necessary concerning the charging method, device and the effect of this method on the coke oven operation.     

制备工艺对炭/石墨密封材料性能及其结构的影响

以改性的填料（二次焦）为骨料炭,中温煤沥青为黏结剂来制备炭/石墨密封材料,考察了材料制备工艺条件对材料机械强度、开孔率以及微观结构的影响。研究表明,与传统的炭/石墨密封材料制备工艺相比,利用改性后的骨料炭所制备的炭/石墨材料具有较高的机械强度和相对均匀的孔径分布。此外,随着二次焦热处理温度的升高,最终材料的体积密度和机械强度增大,开孔率降低。当二次焦热处理温度升高到540℃时,最终所得材料的抗压和抗弯强度分别达到210.0MPa和67MPa,开孔率为19.3%。炭/石墨材料经浸渍金属Cu后,Cu颗粒在利用传统工艺制备的材料中的尺寸相对较大,且存在局部聚集或团聚,而在利用二次浆涂工艺制备的材料中则呈细网状结构且均匀分布。     

COPNA树脂炭素材料的制备研究

以超细石墨粉和超细焦炭粉为原料,分别以COPNA树脂、热塑性酚醛树脂以及二者按质量比为3：2的复配树脂为粘结剂,在100MPa下成型,按一定的升温程序在真空烧结炉中烧结,测定样品的体积密度、抗压强度、抗折强度、拉伸强度、气孔率等性能,结果表明,复配树脂的粘结效果最好,COPNA树脂次之,且含量在30％时为最佳。