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A major breakthrough has been achieved in the \"complete set of technologies for the hydrogenation of the entire fraction of medium- and low-temperature coal tar\". Author/Source: Modern Coal Chemical Industry; Date: July 22, 2020; Clicks: 146. On July 20, 2020, the China Petroleum and Chemical Industry Federation organized experts to hold an evaluation meeting for the scientific and technological achievements related to the \"development and industrial application of a complete set of technologies for the hydrogenation of 500,000 tons per year of the entire fraction of medium- and low-temperature coal tar\", a project developed through collaboration among companies such as Xinjiang Xuanli Environmental Protection Energy Co., Ltd., Fushun Petrochemical Research Institute of Sinopec Corporation, Shenzhen Qianhai Xinneng Energy Technology Co., Ltd., Shengbang Technology Co., Ltd., and Maoming Ruipai Petrochemical Engineering Co., Ltd. The evaluation committee believes that this technology is the first of its kind in the world and is generally at the international leading level. The appraisal committee was composed of 7 renowned domestic experts, including Academician Cao Xianghong from the Chinese Academy of Engineering and Academician Xu Chunming from the Chinese Academy of Sciences. Leaders and representatives such as Hu Qianlin, Secretary of the Party Committee and Deputy General Secretary of the China Petroleum and Chemical Industry Federation; Cheng Renjie, Executive Director of Beijing Xuanli Investment Co., Ltd.; Fang Guangxin, Chief Scientist of Xinjiang Xuanli Environmental Protection Energy Co., Ltd. and Chairman of Shenzhen Qianhai Xindeng Energy Technology Co., Ltd.; Guan Minghua, former Chief Engineer of the Fushun Petrochemical Research Institute of Sinopec; and Chen Buning, Chief Engineer of Xinjiang Xuanli Environmental Protection Energy Co., Ltd., also attended the meeting. The appraisal meeting was chaired by Zhao Ming, deputy director of the Science, Technology and Equipment Department of the China Petroleum and Chemical Industry Federation. Results Introduction: Medium- and low-temperature coal tar is a product obtained from the pyrolysis of low-rank coal, and it represents an oil substitute with great potential for development. Since medium- and low-temperature coal tar contains large amounts of heavy metals, mechanical impurities, resins, and asphaltenes that are difficult to handle, if it enters a fixed-bed hydrogenation system, it can easily clog the reactors, leading to frequent shutdowns and the need to replace catalysts, which severely affects the economic efficiency of the plant. Current technologies mostly use vacuum distillation, delayed coking, or fluidized bed reaction methods to pre-treat medium- and low-temperature coal tar, concentrating heavy metals, mechanical impurities, resins, and asphaltenes in bottom ash or petroleum coke. The light components are then subjected to fixed-bed catalytic hydrogenation, resulting in 25–30% of the coal tar feedstock being converted into bottom ash or petroleum coke with low added value. This approach presents problems such as low liquid yield, low cetane number of the hydrogenated oil, short operation cycles for the equipment, poor economic efficiency, and weak resilience to fluctuations in oil prices. In response to the problems and challenges existing in current technologies, this achievement addresses the strategic needs of energy security. Focusing on improving efficiency and promoting transformation and upgrading in the field of coal tar hydrogenation, it integrates various theoretical and technical innovations such as full-range purification technologies for medium- and low-temperature coal tar along with hydrogenation techniques, complete conversion technologies for resins and asphaltenes, technologies for increasing the cetane number of hydrogenated oil product 1 through ring-opening and weak chain-breaking processes, and technologies for ensuring long-term operation of the reactors. For the first time both domestically and internationally, it has solved industry-related challenges such as the removal of metals and mechanical impurities, complete conversion of resins and asphaltenes via fixed-bed hydrogenation, enhancement of the cetane number of hydrogenated oil 1, and ensuring long-term operation of the reactors. As a result, a set of fixed-bed hydrogenation technologies for medium- and low-temperature coal tar that is at the international leading level has been developed, significantly advancing the technological progress and industrial upgrading of China’s coal tar hydrogenation industry. Industrial application: In 2017, Xinjiang Xuanli Environmental Protection Energy Co., Ltd. began construction of a hydrogenation plant capable of processing 500,000 tons per year of full-range medium- and low-temperature coal tar, in the Naomao Lake Industrial Park in Hami, Xinjiang. The plant came online in January 2018 and has since operated stably over long periods of time. In 2019, the enterprise, technology team, and design team carried out a 72-hour self-calibration of this device, and all parameters met the expected levels, with a maximum load of 105%. The test results show that the oxygen content in low- and medium-temperature coal tar in the whole fraction is 6%–8%; the pretreatment technique can reduce the total metal content to below 20 μg/g, the ash removal rate is >80%, and the yield of coal tar after purification is >99% (on an anhydrous basis) ； During the hydrogenation process, the hydrogen consumption is 6%–6.5%, and the yield of C5+ liquids is greater than 94%. The yield of the hydrogenated oil product is 20%–24%, while the aromatic content is above 65%, making it an excellent raw material for aromatics production ； The yield of hydrogenated oil 1 is 70%–75%, with a cetane number of ≥46 and a cetane value of ≥51; it is possible to produce diesel fractions such as 0#, -10#, -20#, and -35# that meet National VI standards (GB 19147-2016) in a flexible manner, depending on seasonal changes. Prospects for promotion and application: The national production of coal tar is around 20 million tons per year, and it constitutes an ultra-heavy, ultra-viscous and low-quality oil source. Making good use of these resources to reduce their weight is in line with the broader trend of resource utilization; it not only serves as a supplement to petroleum resources but also enhances the viability of coal tar processing enterprises. At present, China’s annual production of low-grade coal is around 2 billion tons. If all of this low-grade coal is processed using low-temperature carbonization technology, 160–200 million tons of tar can be produced, which is equivalent to more than 80% of the country’s current crude oil production. Thus, the market potential for coal tar in the future is enormous. As domestic energy demand continues to rise and the country’s reliance on imported oil increases, vigorously developing the selective utilization of lower-grade coal as well as coal tar hydrogenation technologies not only aligns with the policies regarding the coal industry and energy development strategies, but it also helps to promote the clean and efficient use of coal. It facilitates the transition to new forms of energy in the coal industry and supports its high-quality development, bringing about significant economic, environmental, and social benefits.