Interaction between a coke and a tar. 1. Influence of the surface chemical functions of coke

The authors studied the relation between oxygen-containing functions of cokes and contact angles of tars on cokes. Using two different cokes, a coal-tar pitch and polymer models, they showed that the coke-tar interactions depend on the hydrogen bonding between the two components and that above a critical value surface-chemical-function content has no influence on coke-tar interactions.     

焦炭气孔率对焦炭热性能的影响

通过研究40kg试验焦炉单种煤焦炭、配合煤焦炭及工业焦炉焦炭的气孔结构及焦炭热性能,得出气孔率对焦炭热性能的影响。焦炭气孔率对焦炭热性能有较大影响,随着气孔率的增加,CRI增加,CSR降低;工业焦炉焦炭气孔率与焦炭热强度之间关系密切,气孔率每增加1％,CRI增加0．48％,CSR降低1．46％。用气孔率预测焦炭热性能,对指导焦炭生产、控制焦炭热性能具有指导意义。     

Quality of coal tar in coke production

The reasons for the differences in coal-tar quality in byproduct-capture shops 1 and 2 at PAOAvdeevskii Koksokhimicheskii Zavod (AKKhZ) are explored. The influence of the below-roof temperature and the factors on which it depends is established.     

油碳复合清洗剂的开发和应用研究

研制出一种除焦油和积碳的复合清洗剂,它由水基碱性清洗剂和溶剂基清洗剂复配而成．通过工程实例论述该清洗剂在施工中的应用和清洗效果．     

针状焦用煤沥青的调制研究

介绍了煤系针状焦用原料的要求及调制方法,讨论了2种工业上原料精制的工艺,并重点阐述了国内外对原料的组分、反应性、软化点、流变性、残炭值和结晶度等方面的改性研究进展。在此基础上对煤沥青调制研究在国内的发展前景进行了展望。     

焦炉上升管中煤焦油流动特性的实验研究

为除去焦炉荒煤气显热回收过程中冷凝结焦在换热管壁表面的煤焦油,以煤焦油高温黏温特性曲线为实验依据,研究了200~800℃煤焦油在普通碳钢管道表面和镀镍涂层管道表面的流动特性情况,并线性拟合出煤焦油流动特性随温度变化的关系方程。结果表明:温度与换热管道表面煤焦油的流动特性之间呈现很好的指数关系;当管壁温度达到400℃左右时,普通碳钢管道表面的煤焦油由于流动特性的改变而基本脱除干净,镀镍涂层管道的温度在350℃左右;镀镍涂层管道在抑制结焦方面明显优于普通碳钢管道,其抑制结焦率在20%左右。     

Possibilities of tar addition to coal as a method of improving coke strength

Tests carried out in a pilot oven, in individual 19-t ovens and for a short time, in a 4.5 m high 54 oven battery, showed that addition of a certain amount of tar directly to any coal mix can improve the coke properties. The experimental procedure adopted for tar addition and the determination of the coke properties are highlighted.     

石油焦对生物质气化中焦油裂解的影响

引言 生物质作为一种清洁可再生能源正在受到世界各国的重视.生物质气化是生物质高品位利用的一种主要技术,但在气化过程中产生的焦油对装置的长周期平稳运行有严重危害,一方面低温时焦油易凝结为黏稠的液体,与灰粒一起堵塞输气管道;另一方面焦油的存在还会降低气化效率[1-6],这在一定程度上影响了生物质气化技术的推广应用,因此有必要采取措施降低气化气中的焦油量.     

煤沥青制备针状焦的研究

通过溶剂-离心法净化原料沥青,应用延迟焦化工艺制备针状焦,考察了在聚合过程中QI含量、温度、压力以及时间对成焦的影响.结果表明,原料中QI含量的减少有利于针状结构的生成,当QI含量小于0.1％时能形成大面积的针状结构;适当的温度和压力能使体系的黏度降低,促进气流拉焦作用,在470℃、0.35 MPa条件下得到的针状焦较为理想;充足的反应时间保证小球的充分融并,反应24h体系能融并、重排,形成良好的针状结构.     

70kg小焦炉的焦油渣配煤实验研究

在600g坩埚和70kg焦炉的放大实验中,以焦油渣为添加剂,气煤、肥煤、1/3焦煤、焦煤、瘦煤组成的配合煤为煤种,进行了焦油渣配煤实验研究。结果显示,添加焦油渣改善了配合煤的黏结性,增加了焦炭产率,提高了焦炭强度和热反应性。确定最佳的焦油渣添加质量分数为3%左右。     

Needle coke formation derived from co-carbonization of ethylene tar pitch and polystyrene

Ethylene tar pitch was co-carbonized with waste polystyrene to prepare needle coke. The modified properties of mesophase, which were greatly improved due to increasing naphthenic and other alkyl content, availed the formation of needle coke with high quality. The coefficient of thermal expansion value was decreased from 3.2 × 10⁻⁶/°C to 0.3 × 10⁻⁶/°C and the optical texture of the coke was changed from coarse mosaic texture to flow domain of high uniaxial orientation after adding waste polystyrene into ethylene tar pitch. The low viscosity of the mesophase pitches favored the development of mesophase and highly uniaxial arrangement. The increase in alkyl group content greatly improved characteristics of the needle coke.     

焦油化工企业高浓度废水的处理方法

针对焦油化工企业高浓度废水的水质特点,选择预处理和Cl O2/UV多级氧化消解相结合的工艺方法 ,尤其是引入紫外光(UV)催化光源,对氧化消解反应的作用效果明显,有机物和COD去除率都较Cl O2单独氧化废水时有很大提高,可有效降低废水中COD和氨氮的含量,使其达到进入生化处理系统的水质要求,且运行成本较常规Cl O2氧化工艺大幅减少。     

Reaction between CO2 and coke doped with NaCN

The role of NaCN as a catalytic precursor in the reaction between coke and carbon dioxide is examined. The experimental work included determination of reaction rate, examination of the chemical stability of NaCN and characterization of coke at various stages of reaction. The extent of sodiumcarbon contact was physically modelled by examining the distribution of potassium in the interior of a KCN doped coke sample after partial reaction.Physical evidence is presented to demonstrate that at 1123 K, the vapor cycle mechanism is the predominant mode of catalysis with catalyst concentration and specific surface area being the two most important directly measureable rate determining factors. Analysis of the rate data on the basis of a structural model demonstrated that when NaCN was used, the enhancement of the rate was inadequate for the diffusion of CO₂ through the porous coke to be important.     

Interaction of shale phenol and tar mixtures with diisocyanates

New adhesives based on shale tars and phenols were prepared by the action of diisocyanate; these adhesives exhibited an adhesive strength of up to 5.6 MPa toward a metal surface (steel 3) and were resistant to alternating temperatures from +60 to ?60°C. Upon the addition of 15–20 weight parts of oil asphaltites, the adhesives became stable to γ-irradiation to a dose of 2.7 × 10⁶ Gy.     

煤干馏生产半焦、煤焦油及干馏炉煤气的发展前景

介绍了国内半焦的发展现状、市场需求及综合效益。通过对半焦各项技术指标与铁合金专用焦的对比及半焦生产与煤制甲醇、煤制油、煤制化肥及煤电一体化等煤化工项目投资、消耗、定员等的对比分析,认为半焦产业发展前景广阔,并对半焦产业的发展提出了建议。     

焦炭反应器防渗炭耐火涂层的研制

为了提高焦炭反应器的使用寿命,降低高炉焦炭冶金性能实验成本,研制了一种用于涂覆焦炭反应器中心电偶管的耐高温陶瓷涂层材料,以隔绝炽热焦炭与中心电偶管镍基合金的炭溶反应,效果明显,效益可观。     

Fissure formation in coke. 2: Effect of heating rate, shrinkage and coke strength

We investigate the effects of the heating rate, coke shrinkage and coke breakage strength upon the fissure pattern developed in a coke oven charge during carbonisation. This is done principally using a mechanistic model of the formation of fissures, which considers them to be an array of equally spaced fissures, whose depth follows a “period doubling” pattern based upon the time history of the fissures. The model results are compared with pilot scale coke oven experiments. The results show that the effect of heating rate on the fissure pattern is different to the effect of coke shrinkage, while the effect of coke breakage strength on the pattern is less pronounced. The results can be seen in both the shape and size of resulting coke lumps after stabilisation. The approach gives the opportunity to consider means of controlling the carbonisation process in order to tune the size of the coke lumps produced.     

Production of isotropic coke by thermocracking of the anthracene fraction of coal tar

The properties of coke obtained by heat treatment of the anthracene fraction of coal tar under pressure (by thermocracking) are investigated. Pressures up to 5 MPa are used; the temperature is 500 or 550°C. For comparison, pitch coke is obtained from oxidized pitch with softening temperatures of 166.2 and 190.2°C. The coke yield from thermocracking is 70–75%. The following properties of the coke are determined: the actual density, the ash content, the yield of volatiles, the optical microstructure, the elementary composition, the change in volume on heating to 2400°C, the impurity composition, and the X-ray structural characteristics. High temperatures (at least 550°C) and heating rate of the anthracene fraction facilitate the formation of a large quantity of active radicals, which instantaneously form the three-dimensional coke structure, preventing the growth and coalescence of mesophase particles; isotropic coke is formed, with a microstructure score of 2.2. At 500°C, anisotropic coke is formed, with a microstructure score of 4.3. Despite the high softening temperature and the content of the α1 fraction, the high-temperature pitch does not form isotropic coke on carbonization. The macrostructure of the coke obtained by thermocracking is monolithic, with fine pores. The thermocracking conditions (temperature, pressure, presence of H₂) facilitate partial destruction and hydrogenation of the heterocyclic compounds. As a result, the coke has a reduced N, S, and O content. For pitch coke, the nitrogen content is 20–40% higher. The lack of ash in the anthracene fraction of coal tar results in ash- and metal-free coke. The coke obtained by thermocracking also has satisfactory X-ray structural characteristics and undergoes practically no expansion on graphitization, in contrast to pitch coke. In view of the technological convenience (absence of liquid products, high coke yield) and the quality of the coke, the production of isotropic coke by thermocracking may be regarded as a promising means of supplying the raw material used to produce artificial graphite.