【Ten Years of Rapid Development in Chemical Equipment】From 1372 to 2024: Hydrogen price drops to 0.7 yuan! Coal supercritical water gasification hydrogen production and power generation combined production technology

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On January 1, 2024, the “Beautiful Yuyang: A Window to Northern Shaanxi” event, which featured presentations of key industries aimed at attracting investment as well as an investment signing ceremony, was held at the China Arts and Crafts Museum and the China Intangible Cultural Heritage Museum. Yuyang District successfully secured 6 investment projects, with a total amount of investment reaching 7.002 billion yuan. Yuyang District signed a tripartite investment agreement for the \"Coal Supercritical Water Gasification for Hydrogen Production and Power Generation Integrated Project\" with Shaanxi China Nuclear Jiaotong Chaojie Energy Technology Co., Ltd. and China Nuclear Huachen Construction Engineering Co., Ltd ； “The “multi-product generation technology for hydrogen production via coal supercritical water gasification,” commonly known as the “supercritical water coal gasification technology,” is a technological achievement resulting from 20 years of research by an academic team led by Academician Guo Liejin from Xi’an Jiaotong University. Data shows that supercritical water coal gasification technology, as a transformative technology, differs fundamentally from traditional coal-fired power generation and coal gasification power generation technologies. Traditional coal-fired power generation, including coal gasification power generation, involves burning coal in air through fire to initiate an oxidation reaction with oxygen; this is an exothermic process. This thermal energy can be utilized; the hot air currents in coal-fired boilers are absorbed by the water inside the boilers, which then turns into steam. This steam is used to drive turbines to generate power, a process commonly known as steam turbine power generation. There is another type of power generation that is more efficient than steam turbine power generation, called gas turbine power generation. Since the material used for this device must be more heat-resistant and meet higher performance requirements, its manufacturing process is particularly difficult. Oxidation reactions naturally produce sulfur dioxide and nitrogen oxides, in addition to particulate matter emitted during coal combustion (the source of PM2.5). To remove sulfur, nitrogen oxides, and particulates, companies need to install dust removal devices. This cost is very high for businesses. Running these devices simultaneously also consumes energy. As a result, the overall efficiency is not high, averaging just over 40 percent. Supercritical water refers to water in which, when the pressure and temperature reach certain values (approximately 22 MPa and 374°C), the density of water expanded by high temperature is exactly the same as the density of water vapor compressed by high pressure. At this point, there is no difference between the liquid and gas forms of water; they merge completely to form a new liquid state that exists under high pressure and high temperature. “\"Supercritical water coal gasification\" does not use air; instead, it simply mixes coal with water to allow them to react. The entire process is not an oxidation reaction; there is no traditional combustion process. Instead, it is a reduction reaction in which hydrogen is burned to produce water. The product resulting from this process is clean, and supercritical steam at high temperature and pressure is generated, which can also be used to drive turbines. The efficiency achieved is higher than that of traditional methods, and there is no pollution. The team led by Guo Liejin from Xi’an Jiaotong University has successfully developed a series of experimental facilities, including a supercritical water fluidized bed, that enable the complete vaporization of coal. Above 700°C, the carbon gasification rate for all types of coal in China reaches 100%. The thermodynamic models, chemical reaction kinetics models, and integrated optimization of the reaction system for hydrogen production via supercritical water gasification have been completed. A pilot-scale demonstration system capable of processing 1 t/h of coal has been successfully developed; through technical and economic analysis, it was found that when the system processes 83.3 t/h of coal, the cost of hydrogen can be reduced to 0.7 yuan per unit. According to previous reports, on February 11, 2018, the first cogeneration demonstration project for the \"technology of producing hydrogen and electricity through coal supercritical water gasification,\" developed by the team led by Academician Guo Liejin at the Key Laboratory of Multiphase Flow in Power Engineering at Xi’an Jiaotong University, was officially launched at Xi’an Thermal Power Co., Ltd., a subsidiary of Xi’an Urban Investment Group. This demonstration project involves an investment of 500 million yuan to build a 50MW coal supercritical water gasification cogeneration unit along with its associated facilities. Once completed, the project will achieve zero emissions of sulfur oxides, nitrogen oxides, dust, and wastewater.