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Porous media combustion technology has the problem of high pollutant emissions in the field of gas combustion, especially civil burners, which have low thermal efficiency and high NOx content in the flue gas, some as high as 170ppm. In order to reduce the emission of pollutants and improve combustion efficiency, scholars have achieved many effective methods through research, such as staged combustion, rich and light combustion, flue gas recirculation and combined combustion. These combustion devices have their own unique advantages and can effectively reduce the emission of pollutants NOx. However, they also have the disadvantages of complex structure, low combustion efficiency and large burner volume. Theory and practice have proven that while reducing the NOx content in the flue gas, it often leads to an increase in the CO content in the flue gas and a reduction in thermal efficiency. This is the difficulty in researching and developing low NOx burners. Porous media combustion technology is a novel and unique combustion method. It has the advantages of high combustion efficiency and low pollutant emissions. At the same time, it has the advantages of small burner size, compact structure, wide load adjustment range, and stable combustion. It can be widely used in home heating systems, power equipment, automobile preheating systems, and various civil and industrial production processes. Research on porous media burners can not only alleviate the serious problem of pollutant emissions in the field of gas fuel combustion, but also cooperate with the "West-East Gas Pipeline" project to increase the utilization of natural gas in coastal areas and accelerate the civilian use of natural gas. It has dual academic and engineering value and significance. Regarding the combustion mechanism of gaseous fuel in porous media, foreign scholars (including some domestic scholars) have conducted relevant research work in the aspects of radiation, heat conduction, combustion rate and pollutant emission, and discussed the impact of porous media material properties and structure on the combustion process, proving the mechanism and advantages of some porous media burners for burning gaseous fuel. Domestic research on porous media burners is still in its infancy. Traditional combustion technology is characterized by free flame, and its combustion inevitably has shortcomings such as uneven temperature distribution, small combustion area, and serious pollutant emissions. This is all due to the poor thermal conductivity and radiation performance of the gas. Compared with the premixed combustion method characterized by free flame, the premixed combustion method in porous media is a combustion technology with completely different combustion pathways. It is a novel and unique combustion method. It is a process in which a gas mixture is burned in a special porous medium material that is both high temperature resistant and has good thermal conductivity. As shown in Figure 1, after the gas and air are fully mixed in the premixing chamber, they flow through the preheating zone to be preheated to close to the ignition temperature, and then enter the porous medium combustion chamber for combustion. The existence of porous media causes the gas mixture to vortex, diverge and merge strongly inside the pores while burning, causing violent disturbances, quickly transferring the heat generated by combustion to the surrounding space in the form of convection, heat conduction and radiation, rapidly expanding the combustion reaction zone, increasing the combustion rate and making combustion complete, reducing CO emissions. ； Due to the good heat exchange characteristics of the porous medium (compared to gas), the temperature in the combustion area quickly becomes uniform, maintaining a relatively stable temperature gradient, and at the same time, the maximum temperature can be kept at a low level, reducing the generation of NOX. ； Due to the existence of porous media, the heat generated in most of the combustion area recirculates, which effectively preheats the unburned mixed gas, increases the combustion speed, ensures the stability of combustion, and also increases the load adjustment range. As a stable ignition source during the combustion process, porous media not only maintains stable combustion, but also ensures high volumetric heat intensity. It is precisely because of these combustion characteristics that premixed combustion in porous media can be completed in a much smaller space than a free flame, thus making the burner volume smaller. * * Reduce the scope of its application * * widen. Therefore, as a novel and unique combustion method, premixed combustion in porous media is completely different from the combustion method characterized by free flame. Compared with it, it has the following series of advantages:: It has high combustion efficiency, low pollutant emissions, small burner size, compact structure and wide load adjustment range. Regarding the combustion mechanism of gaseous fuel in porous media, foreign researchers have conducted extensive research on radiation, thermal conductivity, combustion rate and pollutant emissions. However, due to the difficulty of experimental research and theoretical research on porous media itself, the research is still relatively preliminary. Domestic research on porous media burners is also in its infancy. I believe that the porous media burner is used for gaseous fuel combustion, so most of the combustion products produced are gases, which should not produce tar, and the heat generated by combustion is transferred to the surrounding space in the form of convection, heat conduction, and radiation, which expands the combustion reaction area, increases the combustion rate, and makes combustion complete. The following are some articles I found about porous media combustion technology. I hope they will be helpful to your research. At present, porous combustion technology is mainly based on gaseous fuel. There is no relevant information on whether it can be used for solid fuel combustion. Moreover, the current mathematical model of porous media combustion still has flaws and needs further improvement. It requires everyone's joint efforts. Maybe this technology can bear fruitful results in the near future. "Numerical Calculation of Hot Gas Percolation Heat Transfer and Coal Pyrolysis Process in Moving Beds" The hot gas is used to perform percolation heating pretreatment of coal particles before combustion. The influence of hot gas percolation heating in the moving bed on the coal pyrolysis reaction process is studied through theoretical analysis and calculation methods, and a physical mathematical model of the interaction between percolation heat and mass transfer in porous media and coal pyrolysis reaction is established. The distribution patterns of gas-solid temperature and coal pyrolysis volatilization concentration in the particle layer in the bed are studied under different conditions. The calculation results show that, The pyrolysis reaction of coal in the moving bed is closely related to the seepage heat and mass transfer process. Increasing the inlet seepage velocity and reducing the feed amount will cause the thermal penetration area to expand, the temperature level of the coal seam in the thermal area to increase, and the pyrolysis reaction section to shift toward the bed height. In the pyrolysis reaction area, porosity has a great impact on the seepage mass transfer and coal pyrolysis process. The research results have a certain reference for the design and operation of the moving bed coal pyrolysis reaction device.