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The following is Ende’s coal gasification technology, and its advantages are evident from the introduction. Then I would like to ask whether Haiyou’s method is more cost-effective compared to other methods Compare in which aspects. It might be a rather stupid question; I hope experts won’t laugh at it. The Ende atmospheric coal gasification technology was developed through numerous innovations and modifications based on the Winkler coal gasification technology from Germany. Compared with the Winkler fluidized-bed gasifier, the Ende coal fluidized-bed gasifier shares common features while also having its own characteristics, which are mainly as follows: (1) Replacement of the grate with nozzle-based air distribution. The Ende coal fluidized-bed gasifier eliminates the grate used in the original Winkler gasifier and replaces it with a nozzle-based air distribution system; this solves the problem of slag formation at the bottom of the furnace, thereby improving the operational stability of the gasifier, with its operation rate generally exceeding 90%. ⑵ The gas carryover is recycled back to the furnace. By adding secondary nozzles in the upper middle part of the furnace, the fine pulverized coal carried up from the lower part of the bed is further gasified, and the volatiles generated at the lower part of the gasification furnace are further cracked into gas components such as methane ； Additionally, by returning the coarse particulate fly ash separated by the cyclone dust collector to the gasification furnace for use in the reaction, not only is the overall carbon conversion rate during the gasification process improved, but the carbon content in the fly ash can also be reduced to below 20%, thereby enhancing the efficiency of coal energy utilization in the gasification process. ⑶ High gasification efficiency: Since the solid material in the fluidized bed is in a boiling state during normal operation of the gasifier, there is intense contact between the gas and solid phases. As a result, the temperature and concentration gradients throughout the bed layer are very small, which **enhances the chemical reactions as well as the mass and heat transfer processes between the gas and solid phases inside the gasifier. This enables the fluidized bed gasifier to achieve a gasification efficiency that is 3-4 times higher than that of conventional fixed-bed gasifiers of the same diameter operating at atmospheric pressure. ⑷ One of the advantages of fluidized-bed gasifiers is that they can utilize inexpensive pulverized coal. The main requirement is that the raw coal should have high reactivity; low-rank coals such as lignite, bituminous coal, weakly caking coal, and non-caking coal meet this criterion. In China, these types of raw coal are abundant and widely distributed. ⑸ The gasification process does not produce tar, resulting in good environmental properties. In the fluidized bed gasification process, the bed temperature is around 900–1050°C, with a uniform temperature distribution. Therefore, during the gasification process, the tar and other heavy hydrocarbons produced as a result of coal pyrolysis are broken down quite completely, resulting in very low levels of tar, phenols, and similar substances in the crude gas emitted. This **simplifies the gas purification system and reduces environmental pollution. ⑹ It operates stably with minimal maintenance requirements. By eliminating the grate at the bottom of the gasifier, problems such as slag formation at the furnace bottom that used to occur are avoided; the gasifier itself is essentially just an empty cylinder. The gasification furnace consists only of a furnace body lined with refractory material and a removable nozzle; it has no transmission components or vulnerable parts. Moreover, the bed temperature is much lower than that in fluidized-bed gasification furnaces, which reduces the wear and erosion on the refractory material. As a result, fewer requirements are placed on the refractory material, allowing the furnace to operate at a higher rate. ⑺ The production load can be adjusted flexibly. Practice has shown that the production load of the Ende coal fluidized bed gasifier can be adjusted within the range of 40%-110%, which makes it easier to meet the requirements of the production process. ⑻Easy to start and stop the furnace; the gasification furnace can be started and stopped conveniently. To shut down the furnace, the supply of raw coal and gasifying agent can be stopped, allowing the furnace to be shut down within a few minutes. Since the gasifier is lined with refractory material, the cooling rate is slow; it is even possible to introduce a gasifying agent again after several days to restart it. In fact, during the shutdown period, a small amount of air is injected into the gasifier once or twice a day to maintain its internal temperature. This feature is even more practical when gas is used as an industrial fuel gas. ⑼The waste heat boiler has a long service life. Due to changes in the process flow, the wear on the boiler tubes of the waste heat boiler caused by dust carried in the gas has been reduced, thereby extending the lifespan of the waste heat boiler as well as the time between maintenance sessions. ⑽Gas has a wide range of applications. The operation of the Ende coal fluidized bed gasifier can utilize air, oxygen-enriched air, or pure oxygen together with steam as gasifying agents to produce gas with varying compositions and calorific values, thereby meeting the needs of different users. ⑾The amount of steam generated is large. Due to the high temperature of the raw gas exiting the gasification furnace, waste heat boilers are used to recover the sensible heat contained in the gas, thereby improving the overall thermal efficiency of the gasification process. The superheated steam produced not only meets the requirements of the gas production process but also allows for the supply of some excess steam to external parties. ⑿The cost of gas production is low. Unlike fixed-bed gasifiers that can only use lump coal as raw material, the Endo fluidized-bed gasifier uses pulverized coal as raw material. Since pulverized coal has a high yield and large production volume, its price is much lower than that of lump coal, which inevitably results in a significant reduction in the cost of gas production. Furthermore, since fluidized-bed gasification increases the gasification intensity, the coal gas production capacity of a single gasifier **increases**, and the relative production cost also decreases. For example, the coal gas production cost of the Ende fluidized bed gasifier in Jingdezhen is lower than that of the conventional fixed bed gasifier.