The cleaning process for circulating fluidized beds reaches a new level

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On April 26, a reporter from China Chemical Industry News learned from Jinan Huangtai Gas Stove Co., Ltd. that the new atmospheric-pressure circulating fluidized bed gasification technology for producing clean industrial gas, developed in collaboration with the Institute of Engineering Thermophysics of the Chinese Academy of Sciences, utilizes an internal and external material circulation design to drive the gasification process, thereby significantly improving the gasification efficiency, environmental friendliness, and adaptability to different types of coal. By replacing fixed-bed gasifiers with this technology, the cost of gas production is reduced to half of the original level. Experts have determined that this technology features a high gasification efficiency and broad adaptability to different types of coal, reaching an internationally advanced level comparable to that of circulating fluidized bed air-blown industrial gas production technologies. Responsible officials from various applying units agreed that this technology does not produce tar, and the system generates no waste gas or wastewater ； It is clean and environmentally friendly, with high system efficiency. Utilizing coal with a calorific value of 3500–6000 kcal/kg, even low-quality coal with high moisture and ash content can be used; the calorific value of the generated gas ranges from 1250–1450 kcal/Nm3. Moreover, the heat generated can be recovered for use in power generation, drying, heating, and other processes, thereby improving energy utilization efficiency significantly – with an overall energy conversion rate of over 98%. The gas production capacity ranges from 15,000 to 65,000 Nm3/h, meeting the needs of gas users in industries such as coking, ceramics, and chemicals. A responsible official from the company explained that the fuel fed into the furnace undergoes rapid pyrolysis at 1000°C, thanks to high-frequency cycling and large-channel feedback mechanisms. The reaction temperature within the gasification furnace is evenly distributed and easily controllable; the temperature in the furnace chamber ranges from 950°C to 1050°C. The materials can be circulated multiple times, resulting in a long residence time inside the furnace and a high rate of carbon conversion. The gas and fly ash contain no tar or phenols, and the volatile content of the condensed water is zero. Dry methods are used for ash and slag removal, ensuring cleanliness and environmental sustainability, with no wastewater generated. The entire gas station operates on a closed-loop system with circulating water; since there is no tar, there is no longer any risk of the water in the tar tank overflowing during heavy rains and contaminating groundwater and rivers. It is understood that tests conducted in various application units have shown that the system operates stably; in the absence of a backup furnace, the continuous operation rate reaches 95%, and a single furnace can operate continuously for over 140 days. When operating at full capacity, the dust content in the gas exiting the system is below 25 mg/Nm3.