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Ten years of rapid development in chemical engineering technology; praise for the prosperous and strong China. This is just a starting point to encourage more people to participate and contribute to the discussions. HaiChuan becomes even better with your involvement – we welcome everyone to join in the forum discussions. Be careful with fire risks as the heat increases in July. ---------------------------------------------- As of July 7, 2023, the large-scale dry coal powder fluidized bed project with a daily coal input of 3,500 tons (in dry powder form) and a pressure of 6.5 megapascals has been successfully put into operation at Shandong Ruixing Group, and its cumulative operating time has now exceeded 620 days. Gu Zongqin, president of the China Nitrogen Fertilizer Industry Association, said that this marks the successful development and operation of the world’s largest powder gasifier with the highest gasification pressure. It will be recorded in the history of gasification development in China, and it holds great significance for promoting the green and low-carbon development of the industry. At the meeting, Jiang Congbin, chairman of Aerospace Changzheng Chemical Engineering Co., Ltd., stated that the operating rate of the company’s ultra-large 6.5 MPa powder gasification unit exceeds 95.2%; its gasification performance, steam production, and system pressure differences all meet the design specifications, and the unit operates stably. Jiang Congbin said that the long-term operation of large-scale aerospace powder gasification units demonstrates the following: first, during operation, the high-pressure dry powder delivery system functions smoothly, without any interruptions or blockages caused by powder; the gasification process allows for a wide range of operational adjustments, and a load adjustment range of 60% to 100% can be achieved at a gasification pressure of 6.5 megapascals ； Secondly, the unit operates stably and reliably over the long term; the flow pattern in the gasification chamber is well-organized, there are no issues of overheating or blockages in the gasification unit, and the slag accumulation on the surface of the water wall is uniform ； Thirdly, the single-top-mounted multi-channel gasification burner offers high efficiency; its cooling structure on the fire-facing side is well-designed, ensuring long-term operation of the burner ； Fourth, the coal type has been thoroughly studied; the operating parameters and gasification chamber dimensions are appropriately selected, resulting in a high carbon conversion rate and excellent gasification performance ； Fifthly, the structure of the boiler is reasonably designed; its steam production meets the design specifications and operation is stable. Inspections revealed no blockages anywhere in the boiler, and only a thin layer of ash was present on the water wall surfaces, which can be easily removed ； Sixth, the new type of quenching structure ensures stable liquid levels, high safety, reliable operation, and thorough gas-liquid mixing. “The effective gas yield of this gasification unit is 542 kilograms per thousand standard cubic meters of coal used, while the oxygen consumption is 289 standard cubic meters per thousand standard cubic meters of coal used. The carbon conversion rate reaches 99.05%, and the daily coal processing capacity is 3,165 tons. This year, the unit operated at pressures above 6.0 megapascals for over 110 days, with all performance indicators meeting the design specifications. In addition, the waste boiler operates stably, with continuous operation lasting over 6 months; there is no slag formation on its heating surfaces, and the ash accumulation is loose, allowing it to fall off easily during startup and shutdown processes. ”Jiang Congbin said. On September 25, 2021, the super-large aerospace powder gasification unit at Shandong Ruixing was started up for operation; on September 27, gas production was achieved successfully, the entire process chain was operational, and qualified synthetic ammonia product was produced. On September 25, 2022, the project passed the acceptance inspection by the High-Tech Center of the Ministry of Science and Technology. The Shandong Ruixing super-large aerospace furnace has a vertical structure, with dimensions of φ3800/4400×44800. Its gasification pressure is 6.5 MPa. It employs a large-scale waste boiler–quenching type dry coal powder gasification technology, following a semi-waste boiler process: the high-temperature syngas generated in the gasification chamber is first cooled to an intermediate temperature (around 800°C) using a waste boiler, and then further cooled and washed by water quenching. The aerospace company has also developed new methods and key technologies for preventing ash accumulation in large-scale dry coal powder gasification.