Exclusive | Insights from Typical Overseas Models of Deep Processing of Coal Tar for the Development of China’s Coal Tar Deep Processing Industry (To be continued)

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This post was last edited by liaifeng on 2018-9-4 21:31. Overview: Tar has a highly complex composition, containing tens of thousands of organic compounds. 1. They are mainly aromatic compounds, and most of them are polycyclic aromatic compounds with two or more rings; alkanes, alkenes, and cycloalkanes are rare ； 2. There are also oxygen-, nitrogen-, and sulfur-containing heterocyclic compounds ； 3. Oxidized compounds such as weakly acidic phenols and neutral compounds like coumarone, oxofluorene, etc ； 4. Nitrogen-containing compounds mainly include weakly basic pyridine, quinoline and their derivatives, as well as pyrrole derivatives such as indole and carbazole ； 5. Sulfur-containing compounds are thiophene, thiophenol, thiazole, etc ； 6. The number of alkyl compounds of various hydrocarbons in coal tar is very small, and their content decreases as the number of rings in the molecule increases. The properties of the various components in tar differ, but there are many components with similar properties. It is necessary to first use distillation to separate out various fractions, so that the individual compounds such as phenol, naphthalene, and anthracene that are to be extracted can be concentrated in the corresponding fractions, after which physical and chemical methods can be employed for further separation. Approximately 500 different compounds can be identified in coal tar. Germany has the most advanced tar processing and separation technology, with over 250 types of industrially refined products available ； There are about 50 types of products refined by Japanese industry ； Nominally, 120 types are listed for production in our country, but less than 70 of them can be produced on a regular basis. 1 Current status of foreign coal tar resources and the processing industry: The main processing methods are distillation and hydrogenation. The technologies for coal tar distillation and the secondary processing of its fractions are well developed. Compounds such as naphthalene, anthracene, carbazole, acenaphthene, 1-methylnaphthalene, 2-methylnaphthalene, fluorene, and oxofluorene, which are present in high-temperature coal tar, cannot be produced economically through chemical synthesis methods at present. The development of the advanced coal tar processing industry has followed roughly four trends: first, the enlargement of processing facilities for centralized production ； II. It involves the exchange and centralized processing of the main fractions separated from various large-scale coal tar processing units ； Third, significant human, material, and financial resources are invested in the research and development of deeply processed and high-quality products ； IV. It involves integrating coal tar processing enterprises to form large groups and companies. http://mmbiz.qpic.cn/mmbiz_png/mHibIuV9efNsfmeaCkPia5IfM0AXJmrM50WYjVib3wM5zfiaxgyBOjibfIia97baFS7Deu3U6R43aWJ4ibDvnO2hibT9sQ/0?wx_fmt=png Three foreign coal tar-based business models: The first model involves offering a wide range of products in various specifications and grades, through purification and formulation processes. For example, the German company Lütgé produces over 220 different products that are separated and formulated from tar. Naphthalene has 4 grades, resins have 5 grades, anthracene has 7 grades, and asphalt binders and impregnating materials have 20 grades. According to market demands, the operating parameters can be changed on the same device to produce products of different grades, thereby achieving the versatility of the device. The second model: deeply processed products that build on coal tar processing outputs and expand into areas such as fine chemicals, dyes, and pharmaceuticals. For example, Sumitomo Chemical in Japan focuses solely on the purification or further development of pure compounds derived from coal tar, and has developed and produced 180 different products. For example, there are 21 types of phenol derivatives ； There are 32 types of quinolines and their derivatives ； There are 60 types of naphthalene derivatives. Third mode: Focus on processing asphalt-based products. The other fractions obtained from coal tar distillation are not processed and are sold in their mixed form; only the asphalt produced by distillation is processed to increase its added value, which ensures the overall profitability of the tar processing project. Japanese Mitsubishi Corporation, the American company Rilly, and the American company Koppers all produce high-value specialty products in the processing of coal tar asphalt. The needle coke, impregnated asphalt, and carbon fibers produced by Mitsubishi in Japan dominate the market, maintaining a technological monopoly and selling them at high prices. Rilly Company uses coal tar pitch to produce over 20 products, including high-grade pavement oils, asphalt paints, and roof sealing materials. Advanced processing of phenol oil: http://mmbiz.qpic.cn/mmbiz_png/mHibIuV9efNsfmeaCkPia5IfM0AXJmrM50Web4cuMVlvn8q0Rb1xUHT5hiaB010Ql1a2XCcllbVUBKYlQmUWhmCZw/0?wx_fmt=png. Advanced processing of refined oil: http://mmbiz.qpic.cn/mmbiz_png/mHibIuV9efNsfmeaCkPia5IfM0AXJmrM50GuroIrC5yTRvsSJLa53vJb2VmX3iaJSyjyCzJczQiantJFh3JhIDxjicQ/0?wx_fmt=png. The main products obtained through the separation of refined oil include quinoline, isoquinoline, methylquinolines (2-methylquinoline, 4-methylquinoline), methylnaphthalenes (α-methylnaphthalene, β-methylnaphthalene, mixed methylnaphthalenes), indole, biphenyl, acenaphthene, phenanthrene, and oxofluorene. Advanced processing of washing oil: http://mmbiz.qpic.cn/mmbiz_png/mHibIuV9efNsfmeaCkPia5IfM0AXJmrM50lZn2JFR0LUywUVA3hEo4A1UZttdr0209Am2MVAMvpJjwqLJHLIaJgQ/0?wx_fmt=png. This technology features the following advantages: ● It has a wide range of applicable raw materials; it can be used to process not only washing oil but also naphtha oil and methylnaphtha oil. ●It handles a large volume of raw materials, uses high-efficiency packed towers, and yields products with high purity; the purity of β-methylnaphthalene can reach over 98%. ●Both mixed fraction distillation and packed rectifying columns employ negative pressure distillation, which helps to reduce the system temperature and the requirements for materials, thereby ensuring the smooth operation of the system. Additionally, the steam and warm water generated by the device can be fully utilized to reduce its energy consumption. Advanced processing of anthracene oil: The boiling points of anthracene, phenanthrene, and carbazole at atmospheric pressure are 339.9°C, 338.4°C, and 354.76°C respectively. The boiling points of anthracene and phenanthrene are similar to each other, while that of carbazole is quite different from theirs. To carry out the distillation process, the following methods can be employed: Using vacuum distillation to lower the boiling point and increase the relative volatility allows for a reduction in the heating temperature, thereby decreasing the risk of coking ； Adding an azeotropic solvent for azeotropic distillation can reduce the heating temperature and increase the recovery rate ； Adding a low-boiling solvent can act as a stripping agent, as well as reducing the distillation temperature and increasing the relative volatility. (1) Vacuum distillation or solvent dephenylation, followed by distillation and solvent purification, such as the production process used by the French company BEFS ； Alternatively, anthracene, phenanthrene, and carbazole can be separated first by distillation, followed by solvent extraction, as in the production process used by the German company Lütte. The purpose of the distillation-solvent method is the comprehensive utilization of anthracene, phenanthrene, and carbazole; this method is widely used in Germany, the United States, and Japan. http://mmbiz.qpic.cn/mmbiz_png/mHibIuV9efNsfmeaCkPia5IfM0AXJmrM50qmkcxgfjwYdAcd6sQx4mMlhc4OLLynYZbv7iaeA2aY2Haicc60txtYHA/0?wx_fmt=png The traditional sulfonation-alkali fusion process used for the deep processing of industrial naphthalene has some shortcomings: when producing 2-naphthol, it is necessary to remove 10–15% of the 1-naphthalenesulfonic acid isomers. The process of removing isomers consumes a significant amount of energy, results in the loss of some refined naphthalene, generates large amounts of wastewater and waste acid, and at the same time complicates the manufacturing process as well as accelerating equipment corrosion. Naphthalene is sulfonated to yield mixed naphthalenesulfonic acid; through processes such as blowing, neutralization, alkali fusion, acidification, and distillation, crude mixed naphthol is obtained, which is then separated to produce high-purity 2-naphthol. http://mmbiz.qpic.cn/mmbiz_png/mHibIuV9efNsfmeaCkPia5IfM0AXJmrM50icEzPh60JqsaLa7eHnkHU1SbTJqDLDia3MmFgvAmU7c57DJcoCZIKBpg/0?wx_fmt=png Deep processing of coal tar pitch – needle coke. I. Raw material pretreatment: The static sedimentation separation method is used; the purpose of this treatment is to remove impurities from the soft pitch (mainly quinoline-insoluble substances, or QI), thereby adjusting the molecular weight distribution to an appropriate level. II. It consists of three parts: delayed coking, hydraulic decoking, and venting. The refined asphalt passes through a heat exchanger for heat exchange before entering the raw material buffer tank; it is then pumped into a heating furnace and subsequently sent to the coke tower. III. Calcination involves crushing and grading the delayed coking produced in the coking tank, and then subjecting it to calcination to remove volatile components, thereby obtaining qualified needle coke. It adopts a rotary kiln calcination technique and consists of three parts: the delayed transportation of needle coke, calcination, and the packaging and storage of the calcined needle coke. Advanced processing of coal tar pitch – pitch-based carbon fibers: http://mmbiz.qpic.cn/mmbiz_png/mHibIuV9efNsfmeaCkPia5IfM0AXJmrM50LibQ7PBLsLM1DRseRQyKgeKia0eSMgU4RiccC0ibrdkcGxaHN5qhkwCG1A/0?wx_fmt=png At present, over 50% of high-performance pitch carbon fibers are used in the aerospace industry; in the future, due to considerations related to weight reduction as well as shock absorption, their use is expected to expand to railway vehicles and automobiles as well. The demand for asphalt-based carbon fiber in foreign markets is primarily driven by the replacement of industrial PAN-based products and by developments in the aerospace industry (such as the F-35 fighter jet, as well as the A380 and Boeing 787). Advanced processing of coal tar pitch – Advanced processing of carbon fiber coal tar pitch – Isostatic graphite http://mmbiz.qpic.cn/mmbiz_png/mHibIuV9efNsfmeaCkPia5IfM0AXJmrM50LQXuP4AibHfCa5KsibdFRt1Enic32UQ2A0YIxW5tRWrZF4DibdHgLG1yyA/0?wx_fmt=png Production abroad is mainly concentrated in three companies: Japan’s Toyo Carbon Co., Ltd., France’s Roland Carbon Group, and Germany’s SGL Group. All three of these companies have production facilities in China as well. http://mmbiz.qpic.cn/mmbiz_png/mHibIuV9efNsfmeaCkPia5IfM0AXJmrM50hibja3Hmibo0uyQE7U6ibuFPZAQzTwbNQibiazMoNuP4ZG9xLzlc3vBZ6Ew/0?wx_fmt=png http://mmbiz.qpic.cn/mmbiz_png/mHibIuV9efNsfmeaCkPia5IfM0AXJmrM50HGEYsyPG5fAP5guZndqLJaw5EONOdn3Isc1le7NASMxrUVHVGCIITg/0?wx_fmt=png http://mmbiz.qpic.cn/mmbiz_png/mHibIuV9efNsfmeaCkPia5IfM0AXJmrM50lONrtZdIhsJyktUtpR0nGZjdibWUOHLibny9fD6G2T15zaYeKWzgMsgA/0?wx_fmt=png http://mmbiz.qpic.cn/mmbiz_png/mHibIuV9efNsfmeaCkPia5IfM0AXJmrM50lmcgDRIN3v76QpGuzxJa8LRg0KrNNiayicpDQicVZ2kWHjkMIol5zg9uQ/0?wx_fmt=png http://mmbiz.qpic.cn/mmbiz_png/mHibIuV9efNsfmeaCkPia5IfM0AXJmrM50TyzhGOIRxpAnCnqsSS3x8ZbXk3hYqpraQKlI9nEtWWIeZnHkdtWqyA/0?wx_fmt=png http://mmbiz.qpic.cn/mmbiz_png/mHibIuV9efNsfmeaCkPia5IfM0AXJmrM50toy6diaWA71icibGFgDYpV2RzNwNUCS6Y7x8S164J9trcthIgCKFNIDOg/0?wx_fmt=png http://mmbiz.qpic.cn/mmbiz_png/mHibIuV9efNsfmeaCkPia5IfM0AXJmrM50NJo0YPicYd2iclGysxyib4QmZReWEohmorvs3JHunJt6EGDMWtatjvvKg/0?wx_fmt=png http://mmbiz.qpic.cn/mmbiz_png/mHibIuV9efNsfmeaCkPia5IfM0AXJmrM50wWNbjBD9hVSWe0dpXA5QZJgGKeNgU5IiboLBKqeMIsohMTqMkSs3Isw/0?wx_fmt=png http://mmbiz.qpic.cn/mmbiz_png/mHibIuV9efNsfmeaCkPia5IfM0AXJmrM50uW4JibLRxstjeKHSzjMVPbXqMOJJCpnOrayVpibcVIyGy1RZ6hNlxxXw/0?wx_fmt=png http://mmbiz.qpic.cn/mmbiz_png/mHibIuV9efNsfmeaCkPia5IfM0AXJmrM50NSYPUotPWM8o9fr8UR8m9a5uib5nlwGAnGq9BhAyJxZ53ibp6t5icb8vw/0?wx_fmt=png Source: 2016 National Forum on Deep Processing of Coal Tar and Hydrogenation Technology Industrialization Author: Bu Xinping, Senior Engineer from the Industry Development Department of the China Petroleum and Chemical Industry Federation http://mmbiz.qpic.cn/mmbiz/cZV2hRpuAPhu*bIOsThcH7HF1lpQ0YvkVxZRNLHj5sOYQUIZwNnK4bicCxIqXR9Ie9TgFTkWzPhzGLRde2Y9dSA/0 Notice from the National Coal Tar Deep Processing and Hydrogenation Technology Cooperation Group regarding invitations to join this group. As a major by-product of coal chemical processing, coal tar plays an important role in modern coal chemical industry, and its deep processing is an essential part of it. The deep processing routes for coal tar rely primarily on chemical extraction and hydrogenation processes. Advances in extraction techniques for fine chemicals, increased efforts in the development of downstream products, and the growing maturity of technologies for producing clean fuels through coal tar hydrogenation have all contributed to an improvement in the scale, technology level, and sophistication of the coal tar deep processing industry. The high added value of products derived from coal tar deep processing, along with their potential for further development, are driving this industry toward more concentrated processing, larger-scale facilities, greater diversity in products, and a focus on high-end markets. To strengthen communication and cooperation among enterprises involved in the deep processing of coal tar, as well as to promote technological innovation and breakthroughs in this field, Beijing Coal Chemical Information Technology Co., Ltd. took the initiative to establish the \"National Coal Tar Deep Processing and Hydrogenation Technology Cooperation Group\" (hereinafter referred to as the \"Cooperation Group\") in collaboration with authoritative experts and scholars in the coal tar deep processing industry, as well as relevant organizations. The aim is to make full use of existing resources, create a shared mechanism platform, and build a high-level organizational structure for the coal tar deep processing industry. We hereby invite enterprises involved in the deep processing of coal tar, as well as those in related fields such as engineering design, technology research and development, equipment supply, and universities, to join the collaboration group. For more detailed information, please contact the secretariat of the collaboration group. Contact persons for the Secretariat of the National Coal Tar Deep Processing and Hydrogenation Technology Cooperation Group: Chen Qiang, Wang Zhiguang. Mobile phones: 15810440453, 13681169949. Telephone: 010-85398926. Fax: 010-85398926. Email: meihuake2016@163.com. WeChat group for communication within the cooperation group: Add WeChat at 15810440453, and indicate: Cooperation Group, organization name, position, and name http://mmbiz.qpic.cn/mmbiz/yqVAqoZvDibG6wlFUVibvvuoCyK8g203xOro3M0heA85f2zcGjmesNG0T3EOll2iaZmETKyGbbumLT6wRor227Mmw/0?wx_fmt=png http://mmbiz.qpic.cn/mmbiz_jpg/mHibIuV9efNsfmeaCkPia5IfM0AXJmrM50yECVicfaHMzM5OWiaKWN5QuxNfTQSugEHdnTU70fYC0vxXibbsw9OnQjg/0?wx_fmt=jpeg The 3rd China (Hangzhou) International Symposium on New Coal Chemical Engineering 2017