Major breakthrough achieved in the integrated coal coking tar extraction and syngas production (CCSI) technology

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A major breakthrough has been achieved in the technology that serves as the key to coal utilization and the energy industry revolution – the integrated process of extracting coal tar from coal and producing syngas (CCSI). Recently, the integrated CCSI technology, developed independently by the Research Center for Efficient Hydrocarbon Utilization at Shaanxi Yanchang Petroleum (Group) Co., Ltd., made significant progress; an industrial test plant with a capacity of tens of thousands of tons was able to operate continuously for 144 hours without any issues. The yield of coal tar reached 16.23%, while the effective gas content in the syngas was over 35% (for air-based gasification), with all parameters meeting or exceeding the design specifications. 36t/d CCSI industrial test facility – Site of the CCSI industrial test facility. At present, coal in China is mainly used through direct combustion or single conversion methods, with only its calorific value and certain components being utilized. This not only leads to the waste of valuable components and economic losses but also results in some of these resources being converted into pollutants that harm the environment. Technological innovations in the differentiated utilization of coal and coal-based cogeneration are important ways to achieve efficient and clean conversion of coal as well as its use as a fuel raw material. CCSI technology enables the pyrolysis and gasification of coal to take place in a single reactor, directly converting coal into coal tar and crude syngas. This approach maximizes the utilization rate, conversion efficiency, and added value of coal resources, raising the level of coal utilization technologies to a higher standard. In the future, driven by CCSI technology, coal will be converted efficiently and cleanly into oil (coal tar) and gas (syngas). This will then be integrated with industries that produce liquid fuels, chemicals, and electricity, thereby creating a integrated production pathway for coal, oil, and electricity. This will give rise to a completely new model for energy development, having a significant and profound impact on the development of the coal chemical industry and the pattern of energy utilization in times of low oil prices, while also driving changes in the models of the coal industry and the energy chemical sector. The main technological innovations and industrial advantages are reflected in 5 aspects: the technological approach is innovative. By changing the traditional methods of utilizing coal in different ways, such as coal pyrolysis technology and integrated pyrolysis-combustion technology, and by integrating pyrolysis technology with pulverized coke gasification technology, coal can be directly converted into gaseous and liquid products within a single reactor. This approach not only yields high yields of coal tar but also enables efficient conversion of pulverized coke, allowing for complete utilization of the coal – thus resulting in higher conversion efficiency and greater added value of the products. Energy conversion is efficient. The reactor’s unique fluidization field, temperature field, and channel configuration design, along with the high-frequency circulation of high-temperature solid particles, result in a favorable temperature gradient ； The coupling of gasification and pyrolysis reactions forms a closed cyclic system, in which materials and thermal energy are exchanged between the two processes; as a result, the reaction system reaches self-thermal equilibrium, leading to a significant improvement in the overall efficiency of energy conversion. The environmental benefits are significant. By integrating CCSI technology with the power generation industry, coal tar is extracted while \"gas\" (syngas) is used to generate electricity in place of coal, thereby creating a new type of integrated coal-electricity co-production system that features clean and efficient conversion of coal, advanced processing of coal tar, and green power generation. Syngas contains no heavy metal pollutants such as mercury and arsenic, and it can be desulfurized, decarbonized, and dust-removed before power generation. This approach helps to address the high costs and poor efficiency of existing flue gas treatment systems in coal-fired power plants, by tackling pollutant emissions at the early stages of the industrial chain and thus supporting the \"Blue Sky Initiative\". It offers good economic benefits. The new kerosene-electric combined heat and power production model, with its advantages of high profitability and extremely low emissions, will surely greatly promote the transformation and upgrading of the existing coal-based power industry. At present, China uses about 2 billion tons of coal for power generation each year, and around 70% of the power plants employ subcritical boilers. If all of these boilers were upgraded using CCSI technology, it would not only significantly improve power generation efficiency but also yield an additional 200 million tons of coal tar, which could replace more than 50% of China’s crude oil imports. Furthermore, for newly built ultra-low emission power plants that use the CCSI-gas turbine power generation mode, there is no need to install large-scale air separation units, which significantly reduces the investment required for IGCC technology and enables its commercial application in China at an earlier stage. The market is vast. CCSI’s technological innovations have opened up pathways for the integrated development of coal, kerosene, and electricity production, driving continuous improvement and innovation in coal-based combined production technologies both in depth and breadth. This has facilitated the simultaneous achievement of economic benefits and environmental protection, as well as the creation of industrial clusters and circular economy development models across various industries. It is understood that research and development on CCSI technology began in October 2012, going through stages such as pilot-scale experimental studies, cold-state simulation studies, and the design and construction of a 36t/d industrial test facility. The construction of this industrial test facility was completed in August 2015; the entire process was operational by November of the same year, and significant progress has been made recently. Currently, the preparation of the process package for an industrial-scale CCSI plant with a capacity of 1 million tons per year (3,600 tons per day) developed based on this technology is underway simultaneously, and industrial demonstration and technology dissemination are expected to take place during the 13th Five-Year Plan period.