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Theoretical study on the soot-blowing mechanism of acoustic soot blowers: To address the issue of long-term soot accumulation in boilers, the main device used for soot removal is the soot blower. New theories regarding soot-blowing methods are continually being sought both domestically and internationally; however, based on their principles, the main types of soot blowers include steam soot blowers, gas pulse soot blowers, and acoustic soot blowers. ⑴Steam soot blowers primarily use the impact force of high-pressure steam jets to remove slag and ash deposits from the heated surfaces. It is effective at removing the sticky ash accumulation on the heating surfaces in the furnace and high-temperature areas. However, the use of steam results in increased steam consumption, which reduces the efficiency of the boiler. On the other hand, the impact force of steam increases wear on the tube walls, as well as raising the humidity of the flue gases, thereby increasing their dew point temperature and exacerbating low-temperature corrosion ； Furthermore, the steam soot blower belongs to the contact-type soot blowing method, hence there are significant dead zones for soot removal (as shown in the figure below). http://www.htsker.com/uploads/allimg/181111/1-1Q1110T32KD.jpg For example, the main chemical components of the fly ash from CFB circulating fluidized bed boilers are SiO2, Al2O3, and CaO, etc. It can be used as a clay-like raw material, providing silicon and aluminum components, and it also has high reactivity; it is widely used in the manufacture of building materials such as cement. If a CFB furnace uses a steam soot blower for cleaning, it will introduce a large amount of moisture and wet steam into the furnace; the gas consumption of one such steam soot blower is 0.3 t/h. An excessive amount of moisture and steam entering the furnace can cause the ash to form cement-like lumps, as well as lead to low-temperature corrosion of the heating surfaces at the rear of the furnace. To improve boiler efficiency, CFB boilers employ lower flue gas temperatures compared to pulverized coal boilers; the low-temperature corrosion of the rear heating surfaces reduces the service life of the boilers as well as their operational safety. Considering also the various maintenance issues associated with steam soot blowers, steam soot blowing is not suitable for use in CFB circulating fluidized bed boilers. ⑵A gas pulse shock wave soot remover uses air and combustible gases (such as hydrogen, acetylene, gas, liquefied gas, and natural gas) mixed in appropriate proportions as the working medium. High-frequency ignition takes place within a special container, resulting in deflagration that generates enormous sound energy as well as large amounts of high-temperature, high-speed gas. These gases strike the heated surfaces in the form of shock waves, causing the soot on their surface to be dislodged and carried away with the flue gas. Since this type of soot blower generates high-temperature, high-speed gases, it requires a high level of sealing performance in the pipelines, and the overall maintenance effort for the shock wave soot blowing system is considerable ； On the other hand, since it relies on the deflagration of a mixture of combustible gas and air, there are significant safety hazards ； On the other hand, due to the large amount of combustible gas used, the operating costs are very high ； Finally, since it oscillates, impacts, and washes the surface of the heat exchange tube bundle in the form of shock waves instantaneously, it belongs to contact-type soot blowing; as a result, there are significant dead zones for soot blowing, as shown in the figure below. Currently, this type of dust remover is gradually being rejected by the market. http://www.htsker.com/uploads/allimg/181111/1-1Q1110T415349.jpg⑶ The acoustic dust cleaner uses compressed air as the working medium; under the control of a solenoid valve, the energy of the compressed air is converted by an acoustic wave generator into acoustic energy, which is then transmitted outward in the form of sound waves. Sound waves combine in forms such as direct propagation, penetration, reflection, and diffraction to create a strong resonant sound field that acts on the heated surface, breaking the bond between the ash particles and that surface thereby achieving ash removal. It has no impact on the boiler pressure or the heat exchange surfaces; it requires low operating and maintenance costs, and cleaning is thorough with no dead corners (as shown in the figure below). The technologies involved in the design and use of sound wave generators and controllers all fall under the category of sound wave technology. http://www.htsker.com/uploads/allimg/181111/1-1Q1110TQ1547.jpg Currently, acoustic dust removers are gaining increasing recognition in the domestic market and playing an increasingly important role in practical engineering applications. Zhou Baodong and Wang Guiling compared acoustic dust removers, steam dust removers, and shock wave dust removers in terms of economy, safety, and performance. It points out that the acoustic soot blower has obvious advantages in terms of its structure, soot blowing method, and soot blowing range. In recent years, scholars have also studied devices such as long-range water-based soot removers and microwave soot removers, and have further improved these devices by utilizing modern advanced technologies; for example, our company’s frequency-adjustable high-intensity acoustic wave soot remover.