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Major engineering breakthrough achieved in CSU dual-bed circulating fluidized bed gasification technology Author/Source: Modern Coal Chemical Engineering Date: 2022-11-16 Clicks: 28 Recently, reporters learned from CSU Clean Energy Gas Technology (Beijing) Co., Ltd. (hereinafter referred to as “CSU Clean Energy”) that the 3*20,000 Nm3/h CSU dual-bed circulating fluidized bed gasification unit (hereinafter referred to as “CSU dual-bed”) built for a glass manufacturing company in Shandong Province has been put into operation. Using bituminous coal as raw material and air as the gasifying agent, the unit was able to operate at full capacity continuously for 55 days during the trial production phase; the average calorific value of the produced gas reached 1,550 Kcal/Nm3. This makes it the world’s first large-scale circulating fluidized bed project in which the calorific value of the gas produced using air as a gasifying agent exceeds 1,500 Kcal/Nm3. Image: On March 5, 2022, during the National ** session, **** emphasized while participating in the deliberations of the Inner Mongolia delegation that China’s national condition is characterized by abundant coal, limited oil, and scarce gas, and that the energy structure dominated by coal cannot be fundamentally changed in the short term. To achieve the \"dual carbon\" goals, it is necessary to base actions on national conditions and pursue progress while maintaining stability, achieving them step by step. On March 22, 2022, **Central ***** and Han Zheng, Vice Premier of the State Council, presided over a special symposium on the clean and efficient utilization of coal. They emphasized the need to fully recognize that promoting the clean and efficient use of coal is an important way to achieve the goals of carbon peak and carbon neutrality; it is necessary to address this issue in a comprehensive manner, advance the green and low-carbon transformation of energy in a scientific and orderly fashion, and provide a solid energy foundation for high-quality development. How to achieve clean and efficient utilization of coal is a top priority for researchers working on the clean conversion of coal! As the leader in the research and development of technologies for the clean conversion of coal, the Institute of Engineering Thermophysics of the Chinese Academy of Sciences was the first research institution in China to work on circulating fluidized bed technology, and it boasts the largest team of researchers specializing in this area in China. Research and development on Zhongke single-bed technology began as early as 2004. To date, this technology (hereinafter referred to as “Zhongke single-bed”) has been successfully applied in over 30 projects across industries such as alumina, ceramics, and metallurgy, involving more than 70 units in total. The scale of industrial gas produced using this technology exceeds 28 billion Nm3/year, accounting for 65.3% of the market share, making it the dominant technology for large-scale coal-based industrial gas production. To make further breakthroughs in technologies for the clean and efficient use of coal, a research team built a 5t/d Sino-Science dual-bed technology test platform at the Langfang test site in 2012. In 2022, after years of effort, the Zhongke double-bed technology finally achieved a major breakthrough in engineering applications; test operation data showed that this technology delivered the expected results! Zhongke twin-bed technology is an improvement and upgrade based on Zhongke single-bed technology. The core design concept is to achieve hierarchical conversion of coal through the decoupling of pyrolysis and gasification processes. The principle of this process is shown in Figure 2, while the process flow diagram is presented in Figure 3. By feeding coal in the pyrolysis section, the volatiles in the coal enter the gasification and reduction zone directly after pyrolysis, thereby preventing high-calorific-value volatiles from coming into contact with oxygen at the bottom of the gasifier and being wasted through unproductive combustion ； The recycled semi-coke after pyrolysis exhibits significantly increased reactivity; it undergoes combustion and gasification reactions with the gasifying agent at the bottom of the gasifier. The reaction gases mix with the pyrolysis gases in the reduction zone, where the small amount of large-molecule substances present in the pyrolysis gases are further cracked, increasing the content of H2, CH4, C2H4, and other hydrocarbons in the syngas. Therefore, the calorific value of gas can be increased by more than 10%, with a coal savings of over 3%. The dual-bed gasification technology represents the future development direction of circulating fluidized bed gasification technology, and can be widely applied in fields such as industrial gas, chemical raw materials, and industrial hydrogen production. http://img.yf116.cn/image/img/20221116/87312925154.jpg http://img.yf116.cn/image/img/20221116/8842928420.jpg The six key advantages of Zhike’s twin-bed technology: cleanliness, efficiency, safety, reliability, scalability, and low cost. “\"Cleaning\" is mainly reflected in the fact that gas does not contain large molecular organic compounds such as tar and phenol ； Dry dust removal results in a low dust content in the gas, with the dust level being less than 10 mg/Nm3 ； It consumes little water and produces no organic wastewater. “\"High efficiency\" is primarily achieved through key technologies such as high-rate carbon circulation, decoupling of gasification and pyrolysis, preheating of hot air, efficient waste heat recovery, and re-ignition of residual carbon, thereby enabling a cold gas efficiency of 75% ； The calorific value of the gas is more than 10% higher than that of the Zhongke single-bed technology, resulting in a coal savings of over 3% ； The heat value of air vaporization exceeds 1500 Kcal/Nm3 ； The system-wide carbon conversion rate can exceed 98%. “\"Safety\" and \"reliability\" are primarily reflected in the fact that the device has few moving parts and vulnerable components, resulting in low maintenance needs; it operates stably, is easy to use, features a high degree of automation, has a high rate of safe interlock functionality, is less susceptible to human interference, and can operate continuously for over 8,000 hours per year. “\"Larger scale\" is mainly reflected in the variety of gasification furnace types available; customers can choose from furnaces with a gas production capacity ranging from 10,000 Nm3/h to 80,000 Nm3/h, which can meet the needs of various large-scale gas users. “The low cost is mainly reflected in the fact that this technology has good adaptability to different types of coal; lignite, bituminous coal, and steam coal can all be used as feedstock for gasification. By utilizing inexpensive pulverized coal and undergoing efficient, clean conversion through this technology, the cost of produced gas is much lower than that of similar technologies. This cost advantage is even more evident for users who currently rely on natural gas. Zhongke Qingneng Gas Technology (Beijing) Co., Ltd. was established in Beijing on July 9, 2014. It is a high-tech joint venture founded by the Institute of Engineering Thermophysics of the Chinese Academy of Sciences and Liaoning Fu’an Co., Ltd. The company holds complete intellectual property rights for the circulating fluidized bed gasification technologies of \"Zhongke Single Bed\" and \"Zhongke Double Bed\". Relying on the research and development capabilities of the core team from the Chinese Academy of Sciences, it is dedicated to the development and application of key technologies for the clean and efficient utilization of coal, providing cost-effective clean energy solutions for industrial gas users and contributing to China’s early achievement of its carbon peak and carbon neutrality goals!