Effects of coal rank and reaction conditions upon coprocessing coal with waste tyre

It is well known that the amount of waste tyre increases every year, and a numerous amount of waste tyre is landfilled or dumped all over the world, which causes environmental problems, such as destruction of natural places and the risk of fires. Coprocessing waste tyre and coal is considered as one of the effective processing methods of both materials. Upon coprocessing lower rank coal (Wyoming, C; 68%) with waste tyre, the synergistic effects to upgrading, such as the increase of oil yield and the decrease of residue yield, were appeared. However, the synergistic effects were not observed on coprocessing two kinds of higher rank coals with waste tyre. The reactions of coal with benzophenone were carried out to discuss the hydrogen donatability of coal. Conversion of benzophenone to diphenylmethane on the reaction with Wyoming coal was higher than those of higher rank coals. Accordingly, it was considered that the synergistic effects to upgrading upon coprocessing Wyoming coal with waste tyre were obtained owing to the enhancement of stabilization of radicals from tyre and Wyoming coal through the hydrogen donation from both tyre and Wyoming coal. The effects of reaction temperature and the amount of solvent upon coprocessing Wyoming coal with waste tyre were also discussed in this study.     

Thermogravimetric study of coal and petroleum coke for co-gasification

As a preliminary study of gasification of coal and petroleum coke mixtures, thermogravimetric analyses were performed at various temperatures (1,100, 1,200, 1,300, and 1,400 °C) and the isothermal kinetics were analyzed and compared. The activation energies of coal, petroleum coke and coal/petroleum coke mixture were calculated by using both a shrinking core model and a modified volumetric model. The results showed that the activation energies for the anthracite and petroleum coke used in this study were 9.56 and 11.92 kcal/mol and reaction times were 15.8 and 27.0 min. In the case of mixed fuel, however, the activation energy (6.97 kcal/mol) and reaction time (17.0 min) were lower than the average value of the individual fuels, confirming that a synergistic effect was observed in the coprocessing of coal and petroleum coke. This work was presented at the 6 ^th Korea-China Workshop on Clean Energy Technology held at Busan, Korea, July 4–7, 2006.     

平朔煤显微组分与低温煤焦油及石油渣油共处理的研究

采用高压微型反应釜，将平朔煤的洗精煤以及分离出的显微组分与低温煤焦油、石油渣油在不同反应温度和初始氢压下分别进行共处理，考察了各显微组分的共处理活性，比较了低温煤焦油与石油渣油在共处理过程中的效果，并分析了煤油共处理过程中可能发生的反应。     

Catalytic coprocessing of coal and petroleum residues with waste plastics to produce transportation fuels

Coprocessing reactions with waste plastics, petroleum residues and coal were performed to determine the individual and blended behavior of these materials using lower pressure and cheaper catalysts. The plastic used in this study was polypropylene. The thermodegradative behavior of polypropylene (PP) and PP/petroleum residues/coal blends were investigated in the presence of solid hydrocracking (HC) catalysts. A comparison among various catalysts has been performed on the basis of observed temperatures. The higher temperatures of initial weight loss of PP shifted to lower values by the addition of petroleum residues and coal. The catalysts were also tested in a fixed-bed micro reactor for the pyrolysis of polypropylene, petroleum residues and coal, alone and blended together in nitrogen and hydrogen atmosphere. High yields of liquid fuels in the boiling range 100-480 °C and gases were obtained along with a small amount of heavy oils and insoluble material such as gums and coke. The results obtained on the coprocessing of polypropylene with coal and petroleum residues are very encouraging as this method appears to be quite feasible to convert plastic materials into liquefied coal products and to upgrade the petroleum residues and waste plastics.     

The use of coal liquefaction catalysts for coal/oil coprocessing and heavy oil upgrading

The catalytic hydrogenation of heavy oil and mixed coal-heavy oil (coprocessing) systems has been the focus of a recent study at the Federal Energy Technology Center (FETC). The intent of this effort was to extend the use of coal liquefaction technologies to heavy oil upgrading and coprocessing systems. Specifically, new dispersed molybdenum-based catalysts developed at FETC and a novel silica-doped hydrous titanium oxide (HTO : Si)-supported NiMo catalyst developed at Sandia National Laboratories (SNL) were tested in these systems. The results indicate the potential of coal liquefaction catalysts for use in coprocessing and heavy oil upgrading. High conversions of coal–oil mixtures were observed with dispersed catalyst loadings as low as 100 ppm Mo. Similar results were observed in heavy oil systems. Also, the novel NiMo/HTO : Si catalyst was at least as effective as commercially-available supported catalysts (e.g. Amocat 1C) for conversion of high boiling point material to distillable products and aromatics removal.     

煤炭直接液化技术研究

我国煤炭直接液化技术研究已达到国际先进水平．兖州、天祝、神府烟煤和先锋．沈北、东胜褐煤都是较好的直接液化原料煤。煤直接液化的馏分油最适宜生产高辛烷值汽油、优质喷气燃料和催化重整制取芳烃原料油．两段催化液化由1t无水无灰煤生产5bb1馏分油．煤油共炼与直接液化相比较，简化了工艺过程，改进了馏分油产率和质量。我国煤直接工艺发展方向是煤油共炼或两段催化液化工艺。     

温度对催化裂化油浆与煤共处理沥青性质的影响

用 1 L反应器在煤油比为 1∶ 1 ,在 40 0℃～ 45 0℃的温度范围内 ,研究了温度对共处理反应及沥青性质的影响 .在实验条件下 ,沥青产率最高 .保持同一蒸油温度时 ,所得共处理沥青随反应温度的增加沥青性质发生了有规律的变化 .随温度的增加 ,沥青分子量逐渐下降 ,软化点逐渐下降 .这归结为沥青分子中分子量 >1 0 0 0的分子含量下降 .共处理沥青具有一定的延度 .流变性规律显示 40 0℃时共处理沥青与 Shell 90 # 道路沥青具有类似的流变规律     

兖州煤与大庆减压渣油共处理的研究

采用大庆减压渣油与兖州煤共处理，详细考察了共处理过程对煤液化转化率的影响，并借助棒状薄层色谱（ＴＬＣ－ＦＩＤ）通过对原料组成的考察，论证了大庆减压渣油在共处理过程的作用。结果表明，大庆减压渣油是煤液化的不良溶剂，当它与兖州煤共处理时，能降低兖州煤的液化能力。共处理过程中延长反应时间与升高反应温度有类似的效果，均使甲苯不溶物－前沥青烯含量降低，促进煤液化产物向小分子方向转化。在共处理中大庆减压渣油在     

炼油厂氢气成本及利用效率研究

高效利用氢气是提高炼油企业竞争力的关键因素之一。研究不同原油价格体系下常规制氢方式的氢气成本以及炼油装置氢气消耗与氢气产出,结果表明,煤炭或者石油焦POX制氢在较高油价下可以提供相对廉价的氢气来源。在科威特原油基础上设计的渣油脱碳型、渣油加氢型以及两者组合型4个加工方案,采用轻油差值与氢耗差值的比值来表示氢气利用效率,模拟结果表明,渣油加氢型加工流程的氢气利用效率高于渣油脱碳型加工流程,其中渣油加氢、催化裂化、小型焦化炼油加工流程的氢气利用效率最高,渣油加氢、催化裂化、小型溶剂脱沥青加工流程的氢气利用效率居中。     

A method to predict solubility of hydrogen in hydrocarbons and their mixtures

Knowledge of solubility of hydrogen in hydrocarbon systems is important in design and operation of units and equipments in petroleum and coal processing plants for upgrading fuels quality. In this paper a method based on regular solution theory is proposed for prediction of solubility of hydrogen in hydrocarbons, petroleum fractions and coal liquids at different conditions of temperature and pressure. Hydrogen solubility parameter is calculated through solvent type or its molecular weight. Evaluation of results shows that the method can predict solubility data within the same range of accuracy as those calculated from an EOS or other models while this method is simpler and does not require critical properties of solvent which in most cases cannot be estimated accurately. For more than 400 data points and for systems consisting pure hydrocarbons, coal liquid and petroleum fractions the AAD for the proposed model from estimating solubility of hydrogen and Henry's constant for pressures up to 160 bar was about 5%. The proposed method is applicable to fractions with molecular weight ranging from 70 to 650 which is equivalent to carbon number ranging from 6 to 46. The temperature and pressure ranges are 283-623 K and 1-160 bar, respectively. Solubility range is from 0.01 to 26 mol%.     

Coprocessing of a Turkish lignite with a cellulosic waste material: 2. The effect of coprocessing on liquefaction yields at different reaction pressures and sawdust/lignite ratios

Most of the research works done for alternative energy sources have shown that, in general, coprocessing of coal with biomass-type wastes has a positive effect on the liquefaction yields and these materials are increasingly studied as coliquefaction agents for the conversion of coal to liquid fuels. Addition of biomass waste materials to coal is known to be synergetic in that it improves the yields and quality of liquid products produced from coal under relatively mild conditions of temperature and pressure. This paper reports the coprocessing of a Turkish lignite with sawdust in the category of biomass-type waste material. The experiments have been conducted in a stainless-steel reactor, and temperature and tetralin/(lignite+sawdust) ratio were kept constant at 350 °C and 3:1 (vol/wt), respectively. This is the first time that the influence of reaction pressures on coliquefaction yields was investigated. In addition, the influence of the sawdust/lignite ratios on coprocessing conversion and product distribution was also investigated under the same reaction conditions. The runs were carried out at 10, 25, 40, 55, and 70 atm initial cold hydrogen pressure values and at 0.5:1, 0.75:1, 1:1, 1.25:1, and 1.5:1 sawdust/lignite (wt/wt) ratio values.     

Mild coal extraction for the production of anode coke from Blue Gem coal

The quality and availability of petroleum coke used in the manufacture of carbon anodes for aluminum production is a growing concern to the industry. Coke quality and yields have progressively declined as changes in refinery practice and the move towards processing an increasing proportion of heavier sour crudes have affected coke properties, resulting in an increase in the metal impurities and sulfur content of the coke. An alternative supply of anode coke is required to supplement or eventually replace calcined petroleum coke. The significant domestic reserves of coal could represent a viable carbon resource for anode production, provided defined coke specifications can be met and at a cost that is economically viable.The principal objective of this study was to examine the feasibility of producing anode grade coke by the UKCAER process for the mild solvent extraction of coal. Blue Gem coal from Eastern Kentucky was dissolved in a high boiling point solvent, the mineral matter and unreacted products removed by filtration, and the clean coal liquid converted to coke. The performance of the coal in solvent extraction was compared to a very reactive coal from Western Kentucky. A simple solvent-extraction screening test was established to assess potential candidate materials and process variables without the need for prolonged and complex routines. The coals were assessed in more detail to determine the optimum process conditions by conducting larger scale extraction tests to yield sufficient material for conversion to coke. The green cokes were calcined and the products characterized. The composition and structure of the calcined cokes were compared to typical petroleum coke and assessed for their use in the fabrication of carbon anodes.     

Early coal hydrogenation catalysis

Three inputs were necessary to make catalytic hydrogenation of coal possible. One was the ammonia synthesis which, in 1910, introduced high pressure and temperature into the chemical industry. The second was the experimentation by F. Bergius who showed, in 1913, that coal can be liquefied by adding hydrogen at high pressure and temperature. The liquid products were similar to coal tar. They were not of the quality required for gasoline or diesel fuel production. The use of catalysts to refine the coal oil appeared then to be hopeless since coals contained sulfur, a poison for all then known hydrogenation catalysts. The third input was methanol synthesis in 1923. M. Pier found selective, oxidic catalysts that were less sensitive to sulfur than e.g. the metallic catalyst for the ammonia synthesis.In 1924 M. Pier, in the laboratories of the BASF, prepared sulfur resistant coal hydrogenation catalysts: sulfides and oxides of molybdenum, tungsten, and the iron group metals. With these catalysts it became possible to add hydrogen; split carbon-carbon bonds; and eliminate such heteroelements as sulfur, oxygen and nitrogen from coals and oils. Thus fuels were produced that met petroleum fuel specifications.Optimum catalyst action was achieved by subdividing coal hydrogenation into two stages. The coal was converted, with a dispersed catalyst in the “liquid phase”, into middle oil. This was then hydrogenated over fixed bed catalyst, in the “vapor phase”, to gasoline. On this basis a large scale demonstration plant for the liquefaction of central German brown coal was erected in 1927.The development of catalysts for these two stages proceeded on different routes. Liquid phase catalysts were discarded after one pass through the reactor. They were cheap, or used in very small amounts. It was found soon that coal of different rank required different catalysts, and that the mineral matter of the coal played an important role.The first commercially used vapor phase catalysts were of the hydrorefining type. Hydrocracking activity was achieved by using high temperatures. A great step forward was made in 1930 when a special preparation of tungsten disulfide permitted hydrocracking activity at low temperatures. Thus the first essentially dual function catalyst was found. Its hydrocracking activitity was further increased, and gasolines with a higher octane number were obtained by using it on acidic supports such as materials containing alumina-silica.Such supported catalysts were poisoned by the nitrogen compounds present in coal oils. Therefore a refining step for these oils was needed. The vapor phase was subdivided into the “prehydrogenation” (hydrorefining) and “splitting hydrogenation” (hydrocracking) steps. Further development of catalysts with specific functions for these two steps proceeded rapidly. In addition, separate catalysts were developed for the production of gasolines with a high content of aromatics.The various catalysts developed primarily for the hydrogenation of coal derived oils introduced hydrogen processing into the petroleum refining industry. There they were further modified and improved for the processing of petroleum. These improved catalysts, in turn, will be of help to a future coal liquefaction industry.     

Importance of the textural characteristics of inert additives in the reduction of coal thermoplastic properties

Seven carbonaceous materials of different origin were chosen in order to study the influence of their porous structure on the modification of the thermoplastic properties of a bituminous coal. The materials included were: two non-coking coals, a petroleum coke, coke fines, two residues from tyre recycling and a bituminous residue. The materials were heat-treated to 900 °C to prevent any chemical interaction between the volatiles evolved during co-carbonization. The thermoplastic properties of blends that contained 10 wt.% of additive were measured by means of the Gieseler test. Microporosity was measured by CO₂ adsorption at 273 K, whereas meso and macroporosity were determined by means of mercury porosimetry. The results of the porous structure assessment are discussed in relation to the modification of coal plasticity.     

Effect of process conditions on co-liquefaction kinetics of waste tire and coal

Thermal and catalytic liquefactions of waste (recycled) tire and coal were studied both separately and using mixtures with different tire/coal ratios. Runs were made in a batch tubing bomb reactor at 350–425°C. The effect of hydrogen pressure on the product slate was also studied. Mixtures of tire components and coal were used in order to understand the role of the tire as a solvent in co-liquefaction. In the catalytic runs, a ferric-sulfide-based catalyst impregnated in situ in the coal was used. Both the tire components and the entire tire exhibit a synergistic effect on coal conversion. The extent of synergism depends on temperature, H₂ pressure and the tire/coal ratio. Experiments with coal and tire components show that the synergistic effect of tire is due to the rubber portion of the tire and not the carbon black. The synergism mainly leads to an increase in the yields of asphaltenes, which are nearly double those in the coal-only runs at 400°C. The conversion of coal increases dramatically using the catalyst, but the catalytic effect is attenuated somewhat in the presence of tire, especially at high tire/coal ratios. The data were analyzed using a consecutive reaction scheme for the liquefaction of coal to asphaltenes and thence to oil+gas, both reactions being of second order; a second-order conversion of tire to oil+gas; and an additional synergism reaction when both coal and tire are present, first-order in both coal and tire. Parallel schemes were assumed for thermal (uncatalyzed) and catalyzed reactions. The uncatalyzed liquefaction of coal has a low apparent activation energy, 36 kJ/mol, compared to those for the synergism reaction (84 kJ/mol) and the catalytic coal liquefaction (158 kJ/mol). The conversion of asphaltenes to oil+gas is relatively independent of temperature and of the presence of the catalyst. The catalyst appears to play a significant role in the conversion of coal to asphaltenes, but a negligible role in the synergism reaction.     

煤油共处理过程中的反应机理

主要从煤中键的裂解、氢转移机理以及逆反应等方面论述了近年来在煤液化过程特别是煤油共处理过程反应机理研究的新进展, 着重介绍了溶剂、催化剂对氢转移机理的影响, 指出今后应加强对煤油共处理反应机理的研究, 用于指导将来可能的工业实践．     

煤焦油中渣相的分析及应用

分析了煤焦油中渣相的性质,其具有很强的反应性,可作为一些沥青反应添加剂使用,并在应用方面做了一些阐述.     

煤焦油加工工艺研究

伴随大规模油田的开采,生产煤焦油的低温干馏工艺过程逐步淘汰。但国内仍有大量回收的煤焦油,所以要深入分析煤焦油的特点,作为进一步加工的依据,来系统的分析以及指导煤焦油工艺加工的方向以及过程。     

煤炭直接液化先进工艺的经济性

煤直接液化可以生产液体燃料油。比较了碳氢化合物研究公司（ＨＲＩ）的两段催化液化（ＣＴＳＬ）、煤油共炼和氢─—煤工艺的经济性。煤油共炼可以看作是重质渣油提质和煤液化之间的过渡技术。作出在中国建设煤油共炼示范工厂的经济分析和评价。     

煤酸合成树脂的研究

风化煤氧化制取的煤酸与乙二醇以及热固性酚醛树脂进行缩合反应。煤酸与乙二醇反应的平衡酯收率达４５％，生成的树脂难以固化，但通过加入乙二胺共同反应，可以在２００℃内热压成型，并具有很高的抗压强度。热固性酚醛树脂中羟甲基和煤酸中羧基缩合而成煤酸酚醛复合树胎，该树脂与填充剂混炼后制得的模塑料机械性能较好；而在酚醛模塑粉中混入少量煤酸可以起到加速固化作用。