Assessment of quality of New Zealand coals from borecore analyses

Methods are needed for predicting the properties of as-mined coals from analyses carried out on borecores. Statistical techniques are described for isolating the mean moisture, coal and mineral properties from sets of laboratory analyses carried out on borecores. Comparisons between mine and borecore samples from the same area can be used to derive general methods for predicting properties of mined coal. This Paper deals with the derivation of moisture, ash, voltaile matter, specific energy and elementary composition of coal and minerals for mined coal from borecore analysis results.     

神华煤液化残渣的液化特性研究

液化残渣有着许多不同于未液化煤的特性,研究液化残渣的特性对整个煤炭液化工艺过程以及对液化厂的经济性和环境保护都具有极大的现实意义。通过高压釜液化神华煤液化残渣,从液化恒温反应时间、温度和氢初压对神华煤液化残渣的液化特性影响进行了研究,为煤液化残渣的液化机理研究奠定基础。     

Bioprocessing of coal

A computer-assisted survey and evaluation of the international literature on microbial transformations of coal and relevant organic compounds was performed to identify candidate microorganisms and biological processes potentially applicable to coal bioprocessing. The vast majority of the literature on coal bioprocessing deals with desulphurization via pyrite removal, and some bioprocessing schemes have been proposed. Reports on organic sulphur and metals removal from coal have recently appeared. As yet unevaulated are systems for removal of other elements from coal such as oxygen and nitrogen. However, model substrates resembling certain important O and N functional groups in coal are degraded by microorganisms. These microorganisms could be potentially useful in coal bioprocessing.     

Prospects for biodesulfurization of coal: mechanisms and related process designs

Recent developments in microbiological desulfurization of coal are reviewed. Microbiological removal of organic sulfur from coal remains to be proven conclusively, but is under active study for petroleum biodesulfurization. Microbiological removal of pyritic sulfur from coal is well established in the laboratory and recent efforts have been aimed at scale-up designs and process considerations. Microbiological depyritization may be as inexpensive as other forms of advanced coal desulfurization but it has not been tested on a large scale. Processes based on ‘indirect’ bioleaching of pyrite from coal may also have applications. Other forms of sulfur in coal, such as elemental sulfur, are usually quantitatively insignificant, but nonetheless can be removed microbiologically. Thermophilic bacteria remove pyritic sulfur from coal at faster rates than mesophilic bacteria, in part due to faster abiotic rates of pyrite oxidation at elevated temperatures. Future work in biological desulfurization of coal should include studies on treatment of waste coal or refuse material.     

Determining the coking properties and technological value of coal and coal mixtures

A method is developed for determining the coking properties and technological value of coal from newly identified beds or new sections of existing mines. The coking properties are assessed on the basis of predictions of the strength and reactivity of coke obtained from batch containing coal from single beds and coal blends. The prediction of coke quality is based on the chemical and petrographic characteristics of the coal.     

煤与生物质制氢工艺评述

对国内外煤与生物质热化学转化及微生物转化制氢工艺的研究现状及发展趋势进行了综述,分析了由煤和生物质制取氢气的工艺特点,指出了各种工艺的优势和不足。讨论了日本HyPr-RING工艺和美国FutureGen项目2种煤大规模制氢方案,给出了国内外煤与生物质制氢研究进展和现阶段的氢能选择。     

由煤制取芳烃化合物的研究进展

综述了国内外由煤制取芳烃化合物的三种思路：一是通过将煤直接进行液化获取,或者先将煤液化再从产物中获得芳烃化合物;二是先对煤进行溶剂抽提,然后对产物分类加工制取芳烃化合物;三是将煤进行氧化处理来获得高价值的芳烃化合物。分析了由煤制取芳烃化合物的所面临的产物分离困难、污染环境等问题,并指出了今后需要在分离工艺和催化剂以及如何实现煤的定向转化等方面进行重点研究。     

Coal and coal ash characteristics to understand mineral transformations and slag formation

A knowledge of the composition and structure of minerals in coal is necessary in order to understand the mineral transformations and agglomerate or slag formation during combustion or gasification. Coal ash fusibility characteristics are difficult to determine precisely, partly because the ash contains many components with different chemical behaviours, and may vary from coal source to coal source.The first objective of this study was to determine if the most relevant characteristics of coal were representative of the typical coal from the South African Highveld region. Secondly, a detailed understanding of the coal and coal ash are needed in order to explain slag formation and mineral transformations.Based on standard coal properties, such as the ash content, volatile content, carbon content and maceral composition, it can be concluded that the coal sample used for this study was representative and comparable with the coal from the Highveld region.From the results obtained and the analysis done on the coal samples, it was observed that the mineral grains showed a wide range of types that ranged from pure coal to pure minerals. The types of mineral particles within the coal range from large irregular minerals to small irregular minerals on the edge of coal particles. Kaolinite and quartz can occur as fine inclusions in carbon rich particles or associated with mudstone, siltstone or sandstone, together with kaolinite infillings. The main minerals present in the coal feed are kaolinite, quartz, dolomite, calcite, muscovite, pyrite and microline. An abundance of calcium-rich particles, which are probably calcite and dolomite, were observed. These minerals are present throughout the coal structure and are not specific to one type of mineral grain or structure. An increase in Si and Al abundance in three different prepared coal fractions with increasing particle size distribution was observed the high density fractions are mainly situated in the coarser particles.After combustion or gasification, the major source of glass is derived from included minerals in carbon rich particles. It is clear that focus on the modification of the unclassified/amorphous phase, to increase viscosity (decrease slag formation or have a higher concentration of crystalline phases) at a certain temperature, or in general terms the ash fusion temperature of the coal, is important. Altering the ash chemistry involves the addition of a material to the coal to increase the viscosity.     

对焦炭界面结合状况影响的研究

研究了配煤粒度及添加沥青对无烟煤配合炼焦所得焦炭的界面结合状况的影响情况。结果表明,在配煤比、堆密度相同的情况下,适当降低装炉煤粒度,有利于界面结合。沥青在配料中对煤有不同程度的改质,从而增加了容惰性组合的能力和改善了界面结合状况。     

煤低温热解液体产物中的酚类化合物(Ⅱ)回收

煤低温热解液体产物中酚类化合物的含量约10％～30％，对其进行有效和合理的回收具有重要的现实意义。该方面的研究工作尚属起步阶段，高温煤焦油中酚类化合物的回收情况可提供有益的借鉴。笔者结合自己的研究实践和认识，评述和探讨了在现有工作的基础上如何使该方面研究取得突破性进展，并提出了今后应开展的工作和研究方向。     

Coal gasification by microwave plasma in water vapour

The influence of several parameters on the H₂ and CO yields from gasification of a coal (Blanzy) by microwave plasma in water vapour, in a static system, is discussed. The yields of H₂ and CO significantly increase for low coal weights placed in the discharge illustrating that the gasification occurs on the surface of the coal layer. The time necessary for complete gasification and the gasification yields are measured for several initial weights of coal. The relative yields of H₂ and CO depend on the initial water vapour pressure and are independent of coal granulometry. The reactivity of a coal which was pre-reacted in the discharge is similar to that of an original coal, so a possible recycling of the solid can be envisaged.     

我国煤系针状焦的研究及生产状况

概述了中国煤系针状焦的研究发展过程,讨论了国内煤系针状焦的基础理论研究及工业试验、生产状况,着重介绍了原料预处理、延迟焦化制备生焦和回转窑煅烧的煤系针状焦生产工艺过程,评价了目前国内煤系针状焦的质量和应用状况。     

The mechanism of hydrocarbon synthesis from CO and H2 on cobalt catalysts

Basic process for manufacturing liquid fuel and valuable chemicals from nonpetroleum feedstock (coal, natural gas, biomass) is the synthesis of hydrocarbons from CO and H₂ on catalysts containing Group VIII transition metals. There are also other processes for producing hydrocarbon mixtures from nonpetroleum feedstock (for example, coal or biomass hydrogenation, coal devolatilization and pyrolysis), but the preferential development of the Fischer-Tropsch process confirms its viability and prospects, which are determined by a huge source of raw materials—coal reserves in the energy equivalent are an order of magnitude higher than those of crude oil.     

A correlation between composition and explosibility index for coal dust

A composition index for coal and an explosibility index for coal dust are defined. The first is based on the proximate and ultimate analysis of different types of coals, ranging from lignites to anthracites. The second index depends on the explosibility parameters of coal dust determined by means of laboratory tests, such as the Hartmann Tube and the Godbert-Greenwald Furnace. Through a canonical correlation analysis, three regions of danger for coal dust are established; these represent safe coals, dangerous coals and very dangerous coals. The theoretical percentage of incombustible dust required to make the coal dust inert is determined.     

主焦煤配入比例对焦炭热反应性的影响

在40kg焦炉上进行了多方案的配煤炼焦试验,并对单种煤及配合煤炼焦的焦炭热反应性进行了分析,结果表明,单种焦煤炼焦时25JM的反应后强度最好;配合煤中控制主焦煤的配入比例,适当配入14SM、1／2ZN或26FM后,焦炭的热反应性比单种焦煤炼焦的效果好。     

Comparison of methods of predicting the higher thermal combustion of coal

Formulas for predicting the higher heat of combustion of coal on the basis of technical analysis (the yield of volatiles), elementary analysis, and petrographic analysis are verified. It is found that the formulas are only valid for the samples used in their derivation. Statistical analysis of data for coal from the Donetsk and Lvov-Volynsk basins shows that the higher heat of combustion of such coal is most accurately described by a mathematical formula in which the predictors are petrographic characteristics of the initial coal components, including the reflection coefficient of vitrinite. The mean higher heat of combustion may be determined for vitrinite at different metamorphic stages (for ranks from D to T) and also for liptinite and the sum of fusinized (lean) components in Ukrainian Donetsk and Lvov-Volynsk coal.     

煤的超临界流体抽提研究进展

超临界流体抽提技术是一项新型、绿色、环保的技术，超临界流体抽提技术应用于煤的目的分为超临界条件下气化制氢，超临界条件下脱除杂质和超临界条件下煤的液化3个方面，综述了超临界流体抽提技术应用于煤的研究进展，并着重论述了该技术应用于煤液化的研究进展，指出了今后的研究方向。     

粘结剂用沥青的生产

介绍了几种国内外粘结剂用煤焦油沥青的生产工艺,简明分析了每一工艺的特点,并根据国内外煤焦油加工的现状,对提高我国粘结剂用煤焦油沥青质量提出了建议。     

分子煤化学与煤衍生物的定向转化

从煤中获取“特异化学品”是煤炭非燃料利用的重要途径,对煤大分子进行“剪裁”,获取“特异化学品”和对这些“特异化学品”进行“缝制”是分子煤化学的两个重要内容,总结了煤衍生物的种类及它们可以获取的高附加值产品,分析了煤衍生物定向转化的合理途径,指出了煤衍生物定向转化中存在的问题,并提出解决办法。     

Technological value of coal. 1. Clinkering coal

The concept of technological value is discussed. On that basis, a method of assessing the technological value of coal is recommended. The technological value of the basic clinkering coal in coking batch (Zh, GZh coal) is assessed. Similar estimates are presented for poorly coking GZhO and Zh coal, with somewhat inferior clinkering properties. Three levels of technological value are identified for clinkering coal: the first level includes Zh and GZh coal from enterprises in the Kuznets and Pechorsk basins; the second includes GZhO coal from the Raspadskaya and Vorgashorskaya mines; and the third includes G coal from the Kirov mine. GZhO and G coal from other enterprises in the Kuznets Basin does not function as clinkering coal.