【Ten Years of Rapid Development in Chemical Engineering Equipment】1845–2016: Breaking monopolies – Operation of two-stage dry coal powder pressurized gasification units

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Safety first. Prevention first – let’s give praise and support to the achievements in China’s chemical engineering technology and equipment. **********************【Ten Years of Great Development in Chemical Engineering Equipment】Continuous updates and summaries are available; feel free to join the discussions at https://bbs.hcbbs.com/thread-3576046-1-1.html (Source: Haichuan Chemical Engineering Forum) ***************** The two-stage gasification unit has operated steadily for 117 days: Dry coal powder pressurized gasification technology breaks monopolies. As of August 18, the two-stage dry coal powder pressurized gasification furnace at Huaneng (Tianjin) Gasification Power Generation Co., Ltd.’s IGCC power plant had been in operation continuously for 117 days. This demonstrates that the two-stage dry coal powder pressurized gasification system, developed with Huaneng’s own intellectual property, enables full recovery of waste heat from the gasification process, resulting in a thermal efficiency of over 97%; its stability of operation is at the world’s advanced level. Wang Xiangping, deputy general manager of Huaneng Tianjin IGCC Power Plant, said in an interview with a reporter from China Chemical Industry News that the gasification unit at this demonstration plant uses a two-stage dry coal powder pressurized gasifier with a capacity of 2,000 tons per day, which is based on Huaneng’s own intellectual property. The construction of this plant took 38 months, which is 1 to 2 years less than the time required abroad. It is reported that for a considerable period of time, China’s large-scale fluidized-bed pressurized gasification technology relied heavily on imports; in particular, the full waste heat recovery technology for dry coal powder pressurized gasification was long monopolized by foreign gasification technologies. The gasification technology R&D team at China Huaneng Group Clean Energy Technology Research Institute Co., Ltd. has spent over 20 years conducting extensive basic research on gasification as well as key technologies related to fluidized-bed gasification. They have also carried out in-depth studies on various successful foreign technologies for coal-water slurry gasification and pressurized dry coal powder gasification. On this basis, and taking into account the variable characteristics of coal quality in China, Dr. Xu Shisen, the project leader, focused his research on dry coal powder pressurized gasification – a method that presents greater challenges but also offers better adaptability to different types of coal, as well as improved energy-saving and environmental benefits. He innovatively introduced the principle of chemical quenching and developed a technical setup for two-stage dry coal powder pressurized gasification. By adopting a two-stage pulverized coal gasification process, the high-temperature gas generated in the first stage reacts with the pulverized coal and steam fed in the second stage, thereby increasing the efficiency of the cold gas by 1–3 percentage points and reducing oxygen consumption by 10%–15%. The amount of quench gas required for cooling the high-temperature gas also decreases significantly. Compared with gasifiers that use similar foreign technologies, in dry coal powder pressurized gasifiers with a coal feeding rate of 2,000 tons per day, the quench gas flow rate is reduced by 100,000 to 150,000 Nm3/h, thereby reducing the electrical consumption of the plant itself. The size of the gas cooler has been reduced by over 30%, and the diameter of the high-temperature, high-pressure fly ash filter has decreased from 6.55 meters to 4.6 meters. The cost of the gasification unit is half that of similar foreign gasifiers; compared to the 5–8 year service life of such foreign units, the Huaneng gasifier can operate continuously for a longer period of time, less than 3 years. During operation, its average load is 5 percentage points higher than that of similar domestic units using imported technology. Since it began generating electricity on November 6, 2012, and in the absence of any existing experience in terms of technology and management in this field in China, Huaneng Tianjin IGCC has continued to carry out technical upgrades and thorough debugging. It has overcome a series of technical challenges, including unstable combustion in the gasifier, blockages of ash and slag inside the furnace, frequent leaks in the burner covers, and difficulties in testing different coal types. Just 16 months after operation began, the unit was able to operate at full capacity, exceeding the performance levels of similar foreign units during the same period. The stable operating time increased from 84 days to 117 days or even longer, thus achieving the goal of \"stable, long-term, full-capacity, and high-quality\" operation. Wang Xiangping told reporters that China’s resource profile of abundant coal, limited oil, and scarce gas determines that the energy structure dominated by coal will not change in the short term, and two-stage dry coal powder pressurized gasification furnaces will surely be widely adopted. Link: The gasification unit at Huaneng Tianjin IGCC demonstration power plant uses a two-stage dry coal powder pressurized gasifier with a capacity of 2,000 tons per day, which is based on Huaneng’s own intellectual property. The construction of this facility took 38 months, which is 1–2 years less than the time required abroad. To date, following the successful demonstration of Huaneng’s gasification technology in IGCC power plants, contracts for the transfer of this technology have been signed with more than 10 companies, including Sinochem Group, Sichuan Jinxiang Group, and Shaanxi Fugu Hengyuan Coal-Coke-Electrochemical Co., Ltd. A contract was also established with the American company Ember Clear to export this gasification technology to the United States for use in its IGCC projects.