【Ten Years of Rapid Development in Chemical Engineering Equipment】2016–2020: China’s first ultra-high temperature and pressure fly ash incinerator was successfully commissioned
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Happy May Day 2024! Safety first. Let’s give praise and support to the achievements made in China’s chemical engineering technology and equipment. **********************【Ten Years of Progress in Chemical Engineering Equipment】A continuously updated summary post is available; feel free to join the discussions at https://bbs.hcbbs.com/thread-3576046-1-1.html (Source: Haichuan Chemical Engineering Forum) ***************** At 15:08 on May 9, 2020, the world’s first 130t/h circulating fluidized bed gasification fly ash incinerator, utilizing technology developed by the Institute of Engineering Thermophysics of the Chinese Academy of Sciences, was successfully ignited for the first time in Gao’an, Jiangxi. This marked the beginning of the hot-testing phase for this type of incinerator. At the project site, steam purging is being carried out in an orderly manner. This fly ash incinerator is Unit 1 of the 3 fly ash incineration units installed for the Jiangxi Jimin Kexin (Gao’an) Clean Industrial Gas Project. The Ga’an project is a centralized clean industrial gas supply project funded by the Jimin Kexin Group. It was established with the aim of optimizing the energy structure of Ga’an City, which is known as the \"China Building Ceramics Industry Base\", promoting the circular transformation of the industrial park, and fostering the development of clean energy and environmental protection industries. The project covers an area of over 1,600 mu, and it is planned to build a complete coal-based clean industrial gas plant capable of producing 13 billion cubic meters of such gas per year, with a calorific value of 1,500 kcal/Nm3; a power generation facility utilizing waste heat and energy will also be installed as part of this project. The project is constructed in two phases; Phase 1 is designed to have an annual gas production capacity of 9 billion cubic meters, with a total investment of around 6 billion yuan. Upon completion, the project will become the world’s largest coal-based clean industrial gas project, supplying coal-based clean industrial gas to over 40 enterprises in the ceramic industry base. In the first phase of the project, 16 circulating fluidized bed gasifiers with a capacity of 62,000 Nm3/h and 3 circulating fluidized bed fly ash incinerators with a capacity of 130 t/h and super-high temperature and pressure along with reheating are to be constructed, utilizing the gasification and combustion technologies developed by the research institute. The combustion technology used in the fly ash incinerator was developed by the research institute, with support from the Chinese Academy of Sciences’ strategic pilot science and technology project titled “CFB reburning technology for gasified ash and fine powder ash, as well as high-temperature steam generation technology.” Aiming to achieve clean and efficient utilization of coal, the institute focused on the gasified fly ash generated during the coal gasification process. Building on its more than 30 years of experience in circulating fluidized bed coal combustion technology, it worked to overcome the technical challenges associated with the fine particle size, low volatiles, high ignition temperature, difficult combustion behavior, low burnout rate, and difficulties in comprehensive utilization of gasified fly ash. As a result, a technology for fluidized combustion of gasified fly ash to produce high-temperature steam was successfully developed. Previously, this technology has completed pilot tests with a daily processing capacity of 5 tons of fly ash, industrial trials with a daily processing capacity of 40 tons of fly ash, and an engineering demonstration project at a medium temperature and pressure level of 20 t/h for the processing of 100 tons of gasification fly ash per day. The 130t/h ultra-high temperature and ultra-high pressure circulating fluidized bed fly ash incinerator designed and constructed using this technology uses the gasification fly ash generated by 16 circulating fluidized bed gasifiers as fuel; it is capable of processing 500 tons of such fly ash per day, with a rated evaporation capacity of 130t/h, a steam temperature of 571°C, and a pressure of 13.7MPa. The ultra-high pressure and ultra-high temperature steam generated by combustion is used for power generation, along with 3 waste heat and energy recovery units, each with a capacity of 45 MW. The fly ash incinerator of this project features a large volume of fly ash to be processed and high steam parameters, which is the first of its kind in the world.
What is a circulating fluidized bed? A fluidized bed is a type of reactor in which gas or liquid is used to keep solid particles in a suspended state as they pass through a layer of granular solids, thereby enabling gas-solid or liquid-solid reaction processes. These include dispersed fluidized beds, packed fluidized beds (bubble beds), bubbling beds, turbulent beds, and gas-transported beds. Suspending a large number of solid particles in a moving fluid so that the particles exhibit some of the apparent properties of the fluid is known as solid fluidization. That is, a circulating fluidized bed. In a circulating fluidized bed, fluidization occurs at an gas velocity higher than the free sedimentation velocity of the particles; the particles are carried away by the gas flow, and after the gas and solids are separated, the solids are recycled back into the bed layer to form the fluidized bed. It has many applications in industry, such as in catalytic cracking, where the catalyst is fluidized by heavy oil vapor streams in a lift pipe and transported while reactions take place. The catalyst deactivated at the top of the riser is separated from the oil and gas and then enters another fluidized reactor [regenerator], where it is fluidized by air and regenerated. The regenerated catalyst is recycled back to the riser, forming a catalytic cracking reactor with a circulating fluidized bed configuration.
What is the resource utilization technology for incineration fly ash? It is generated during the incineration of municipal solid waste; during this process, the organic components in the waste are released in gaseous form； Inorganic substances mainly form solid particulates; the larger particles settle at the bottom of the incinerator and on the grates, and are known as bottom ash. The smaller particulates, on the other hand, remain suspended in the flue gases and enter the flue gas purification system along with them. These particulates account for 50% of the incineration ash, while the remaining part of the incineration ash comes from limestone or activated carbon added during the flue gas purification process. All of these particles are captured in dust collectors such as electrostatic precipitators and bag filters. Additionally, some of the smaller particles settle at the bottom of the flues and chimneys, and these captured and settled particles are also referred to as incineration ash.
【Ten Years of Rapid Development in Chemical Equipment】The first large-diameter polyethylene centrifuge in China was developed successfully from 1688 to 2016: https://bbs.hcbbs.com/thread-5663805-1-1.html (Source: 【Hua Hai Chuan Liu】Haichuan Chemical Forum)