焦油渣对焦炭微观结构及反应动力学的影响

对一种工业废焦油渣的基本性质、结构组成及热稳定性进行了分析,并添加该种废焦油渣于配煤中,使用实验焦炉进行了炼焦实验.应用SCHERRER′S公式研究了焦炭微晶结构的变化,并探讨了添加焦油渣对焦炭微孔结构及碳溶反应动力学的影响.结果表明,添加焦油渣促进了焦炭微晶结构的生长,焦炭微晶结构的网状平面尺寸(La)及堆垛高度(Lc)明显增加,层间距d002减少.碳原子更加容易进行重排并向石墨结构进行转变,焦炭石墨化度增加.添加焦油渣的焦炭微孔结构发生了变化,孔径更细,表面积增加,孔体积下降.就焦炭的碳溶反应而言,焦炭的反应性和反应动力学变化不明显.     

炼焦过程协同处置聚乙烯塑料的实验研究

为了从源头实现固废资源化利用，采用炼焦过程协同处置废塑料是重要途径。文章探究了聚乙烯废塑料（PE）分别与炼焦煤、配合煤（PHM）、密实化的配型煤（PXM）协同炼焦的焦炭性能，并分析PE与炼焦煤共炭化过程的化学反应机制。结果表明：在PHM中添加质量分数4%的PE得到聚乙烯塑料配合煤（PHM-PE4）,PHM-PE4炼焦所得焦炭质量整体看低于PHM单独炼焦。将一定比例的PHM用PE和PXM替代，制得聚乙烯塑料配型煤（PXM30-PE4）,PXM30-PE4炼焦所得焦炭质量优于PHM单独炼焦，此种方法在保证焦炭质量的前提下降低了炼焦配煤成本。PXM30-PE4炼焦所得焦炭相对于PHM炼焦所得焦炭的结构强度提高了2.84%，显微强度提高了1.43%，粒焦反应性降低了2.67%，反应强度增加了9.41%，平均孔壁厚度增加9μm。     

加热制度对干燥煤炼焦焦炭质量的影响

以水分含量为2%左右的干燥煤为实验原料,采用5 kg实验焦炉炼制焦炭,探讨了加热制度对干燥煤炼焦焦炭质量的影响,并运用XRD分析了加热制度对焦炭微晶结构的影响。结果表明,优化炼焦加热制度可以有效改善焦炭质量,随着炼焦终温、保温时间、升温速率的增加,焦炭的抗碎强度和反应后强度均先增大后减小,耐磨强度和反应性均先减小后增大;焦炭微晶结构中层间距d_(002)均有所减小,石墨化度升高,焦炭结构强度增大;在炼焦终温、保温时间、升温速率分别为1 150℃、2.5 h、2.5℃/min时,焦炭的质量最好。     

改善焦炭质量的若干措施

介绍了焦炭的用途和国内外质量标准,提出了改善焦炭质量的有效途径:合理选择配煤煤种和配比;配型煤炼焦;装炉煤调湿炼焦;预热煤炼焦;捣固炼焦;干法熄焦;选择粉碎;添加黏结剂和瘦化剂炼焦;焦炉大型化。     

新炭素材料的发展

新炭素材料的发展操宏学（吉林炭素总厂）１前言碳是人类赖以生存发展的基本元素。但直到上个世纪初，人类仅仅是用天然物加热来制取木炭、焦炭、炭黑等，用作燃料、金属冶炼、油墨印染等方面。到１９世纪，出现了烧结型炭素材料，即以焦炭为原料，添加粘结剂成型，隔绝空...     

文摘

<正>煤沥青对焦炭的浸润性及其在核石墨制备中的作用[刊,中]/郭文利,王晨,董得民,等//炭素,2013(4):3-9在炭素材料的制备过程中,黏结剂沥青对骨料焦炭颗粒的浸润性对炭素材料的生产工艺以及最终产品的强度、耐磨性都有重要影响。在研究中,人们先后采用润湿角法、液滴测试技术、渗透层厚度法以及结焦实验对煤沥青/焦炭的浸润性进行表征和检测。沥青的化学组分和结构、焦炭的粒度、表     

石油焦配煤炼焦试验研究

通过对石油焦的特性研究及配煤炼焦试验,考察其对配煤黏结性能及焦炭质量的影响,研究结果表明,添加石油焦会引起煤的黏结指数下降,加入石油焦配煤炼焦会降低焦炭灰分,提高焦炭硫分,降低焦炭冷强度,提高焦炭热强度。     

热压与熔融碳化物——碳素组合材料

提高石墨材料使用性能的一个途径是,在物料处理过程中添加金属炭化物对石墨进行变性处理。难熔炭化物—炭素型组合材料具有热稳定性强,在2000K以上温度下强度高的特点,而且具有令人满意的抗御各种化学介质腐蚀的能力。制作这样的材料要求发展新的先进的工艺方法。制作炭化物一炭素组合材料有多种方法,如气相沉积、多孔炭素体浸渗、电弧熔融和细散粉末成型法等。其中后两种方法有一定的优点,能够保证由高密度材料制作出相间结合力高和组份配比范围宽的线尺寸制件。     

K和Na对炼焦煤工艺性质及捣固焦质量的影响

在炼焦配合煤中添加K_2CO_3或Na_2CO_3进行捣固炼焦,考察K或Na对炼焦煤工艺性质和焦炭性能的影响,运用DTG分析K或Na对炼焦煤热解质量的影响规律,运用XRD和SEM分析K或Na对焦炭性质的影响规律.结果表明,随着K或Na添加量的增加,炼焦煤的干燥无灰基挥发分(Vdaf)质量分数先增加后保持不变,黏结指数(G)和胶质层最大厚度(Y)减小;K或Na使炼焦煤的热解DTG曲线在200℃出现失重峰,在400℃~600℃之间的热解速率变大.随着配合煤中K或Na添加量的增加,焦炭的冷态强度降低,热态性能变差,焦炭微晶结构中堆垛高度Lc减小,网状平面尺寸La变化不大,层间距d002增大,石墨化度降低;K或Na使得焦炭基质受CO_2破坏的程度加剧,从而降低焦炭结构强度.     

煤中加入负催化剂对焦炭热强度作用研究

通过添加负催化剂的无机酸(A)、氧化物(B)和单质(C)到配煤中炼焦的方式把负催化剂负载到焦炭中，研究了它们对所得焦炭热性质的作用．结果表明，无机酸(A)和氧化物(B)使焦炭冷热强度均下降，单质(C)加入煤中炼焦，无论对单种煤或是配煤，均能明显改善焦炭热性质，且在所研究的范围内，随着加入量的增大，热性质改善增大；对焦炭热性质越差的焦炭。单质(C)对其改善的程度越大．     

石墨碎在电极生产中的作用

通过石墨碎、大庆石油焦、锦州石油焦的对比试验,分析了石墨碎的性能,并通过生产试验,分析了石墨电极生产中加入石墨碎对生产及产品的影响。石墨碎具有真密度高、体积密度大,电阻率、CTE偏低,振实密度、颗粒强度大等优点。在石墨电极生产中加入一定的石墨碎可以提高产品的体积密度、强度,降低电阻率等。     

由盘锦石油焦生产石墨电极的工业化研究

分析了盘锦焦与大庆焦的特性；以盘锦焦为原料生产Ф350mm石墨电极，并对其生产过程中的工艺进行控制。结果表明，通过技术改进，用盘锦石油焦生产的普通功率电极，理化指标达到用大庆石油焦生产的同类产品，通过试用其抗热震性能、抗氧化性能、消耗性能较好，能满足用户的使用要求；采用盘锦石油焦生产石墨电极，可降低制造成本。     

Multi-factors affecting coke solution loss reaction

The coke reactivity index (CRI) of several industrial cokes and their multi-level properties were tested. The multi-level properties included specific surface, apparent porosity, microtexture, graphite crystalline structure, and mineral matter. The factors affecting coke solution loss reaction were evaluated following the literature reports.     

Properties and structure of metallurgical formed cokes

Properties and structure of formed cokes obtained from various raw materials using different technologies and changes of properties and structure of formed and conventional cokes occurring in the blast-furnace process were investigated. In formed cokes, in distinction from conventional cokes, there are many types of structure depending on the kind of raw materials used and on the technology of formed cokes production. Formed fuels have shown a lower degree of homogeneity and arrangement of structure in comparison with conventional cokes. In the blast furnace process a gradual arrangement of coke structure takes place. The process of structure arranging is more intensive in conventional coke. The petrographic composition of original coals has a great effect on the quality of the formed cokes. Based on the results of structural investigations, changes in the technological process can be introduced, to obtain a product of the desired quality.     

Carbonization of pitch: Compatibility of components in carbonization

The carbonization of four kinds of solvent-refined-coal (SRC) pitches was investigated in order to determine the properties required for the formation of needle coke. Although the pitches were free from Ql materials, two of them gave needle cokes, whereas the other two gave mosaic cokes. The BS fractions of all pitches formed needle cokes, and all Bl fractions were infusible and isotropic. A combination of suitable BS and Bl fractions gave a needle coke, whereas another mixture formed a mosaic coke, indicating that the BS and the Bl fractions can be compatible to yield a needle coke. Cocarbonization of the BS fractions from other pitch sources with the Bl from the SRC pitches was further studied to evaluate the compatibility, which has been discussed from the structural viewpoint. Trials to improve the properties were proposed, based on the structural information.     

焦炭颗粒的粒度分布及其微观结构研究

焦炭颗粒是生产碳石墨制品的主要原料，它的粒度组成、分布及其微观结构不仅对碳石墨制品的机械性能和理化性能有一定的影响，而且还直接影响到各生产工序的成品率．为此，主要对粉碎后几种焦炭颗粒的粒度组成、分布及其微观结构进行了研究．并通过分析，确立了焦炭颗粒的粒度组成及其分布规律与粉碎方式和焦炭强度之间的内在关系．     

Prospects for production of structural graphites for nuclear power engineering and other sectors of industry at the Chelyabinsk Electrode Plant Joint-Stock Co.

The results of a study of the properties of VPG-grade reactor graphite based on calcined pitch coke currently used as an alternative to KNPS-grade petroleum coke are reported. Technologies for production of new high-density fine-grained graphites based on calcined pitch coke and uncalcined pitch and resin cokes have been developed. Different shaping techniques — extrusion and hot pressing — have been tested. The newly developed high-density fine-grained graphites display superior physicomechanical properties and can be used for service in modified high-capacity reactors.Translated from Novye Ogneupory, No. 8, pp. 6 – 10, August, 2004.     

A semi-industrial scale study of petroleum coke as an additive in cokemaking

The addition of petroleum coke to a typical industrial coal blend used in the production of metallurgical coke was studied. Cokes were produced at semi-industrial scale at the INCAR coking plant, using petroleum coke of different particle size distribution as an additive. Special attention was paid to changes caused in the textural properties (porosity, pore size distribution, fissures at the interface between metallurgical coke and petroleum coke) which have been found to be responsible for variations in the metallurgical coke quality parameters (e.g., mechanical strength and reactivity towards CO₂). Variation in porosity was found to depend on particle size and the proportion of the additive. The decrease in the microporosity (i.e., pore radius<3.7 nm) of the metallurgical cokes observed when petroleum coke is added to the coal blend, is postulated to be one of the main factors responsible for the decrease in the reactivity of these cokes. The variation of the mechanical strength indices can be explained by the changes in porosity and the quality of the interfaces between petroleum coke and metallurgical coke.     

Apparent catalysis of graphitization. 4. Effect of titanium

Finely divided titanium powder has been added at the 5 wt % level to three calcined cokes of widely different graphitizabilities. After heat treatment to 2700 °C, it was found that the titanium additive enhanced the degree of graphitization for all three cokes. The graphitization enhancement was found to be directly related to the anisotropy of the cokes. Possible mechanisms describing the action of titanium are discussed. The advantages of decreased consumption of graphite and energy per ton of steel may however be negated by machining difficulties introduced by incorporated titanium carbide.     

Alteration of metallic microconstituents in petroleum coke by high temperature treatment

Petroleum coke, which is used as a feedstock for the production of graphite electrodes, construction materials, carbides and other products, may contain a limited amount of metallic microconstituents. One of the procedures for separating metals from “carbonaceous materials” is high temperature treatment (HTT). The paper deals with the results of investigation of the content of microconstituents and their chemical compounds in petroleum cokes before and after the high temperature treatment up to 2400°C. One aim of the investigation was to study the kinetics of metal separation induced by HTT. Experimental results show that metallic micro-constituents in the analysed cokes are mainly present as oxides, silicates, sulphates, sulphides, phosphates and carbides. The types of chemical compounds of the metallic microconstituents present in petroleum coke depend not only on the temperature and time of heating but also on the feedstock and on the type and concentration of microconstituents. During high temperature treatment some compounds are transformed to thermally more or less unstable forms thus facilitating partial or complete separation of metallic microconstituents. Of the identified microconstituents, Si, Al, K, Ca, Fe, Ni, Ti, V, Na, S, P, Cu and Cr, all except iron, titanium and vanadium were separated partially or completely by means of the high temperature treatment up to 2400°C.