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The use of acoustic wave technology for cleaning power plant boilers has a history of 30–40 years worldwide. As early as 1918, Swedes used gunshots to remove soot from industrial flue furnaces. After World War II, England also used this method to clean chimneys in homes, which shows that sound can be utilized more widely through scientific approaches. In 1960, the Swedish company Kockums began developing acoustic dust removers, and they were successfully developed in 1969. After 1993, Swedish acoustic soot blowers were introduced into China and installed on some power plant boilers, achieving relatively satisfactory results. In the late 1980s, some experts from the Chinese Academy of Sciences conducted the first tests of acoustic soot removers on the boilers at Beijing No. 2 Thermal Power Plant. The results were very good, and the system was recognized by the users. And it began to be trially deployed in power plants and petrochemical boilers. Practice has shown that by taking advantage of the various properties of sound waves, it is possible for them to reach the areas that need cleaning from any direction and angle, without leaving any dead spots or areas uncleaned; this makes it an excellent replacement for traditional soot blowers. Currently, acoustic dust removal technology is widely used in industries such as power, petrochemicals, metallurgy, and cement, on equipment such as heat exchangers, dust collectors, and bag filters in boilers (including process furnaces). Acoustic soot-blowing systems are installed directly on boilers not only in projects for upgrading old equipment but also in infrastructure construction. Why has the acoustic wave dust removal technology developed so rapidly in recent years? It has its own characteristics and advantages. A brief introduction is provided below. (1) Acoustic wave dust removal technology: What are the characteristics of acoustic waves? Why can sound waves remove dust? 1) Physical properties of sound waves: First, it should be clear that sound waves with a frequency (cycles per second) within 20 Hz are called infrasound waves, which cannot be heard by the human ear ； Frequencies above 20,000 Hz are called ultrasonic waves, and they are beyond the range of human hearing ； The range between these two, namely 20 Hz to 20,000 Hz, has a audible quality and is known as audible waves. The sound waves we use for dust removal are all of low frequency, generally below 300 Hz. Why is that? (1) Low-frequency sound waves have long wavelengths and large amplitudes, as well as slow attenuation (they are not easily absorbed). (2) The radiation angle of low-frequency sound waves is spherical, 360 degrees, that is, in all directions. (3) It can propagate in solids, liquids, and gases. (4) Just like light, it can be reflected and refracted; similarly to electromagnetic waves, it can undergo diffraction. It has strong capabilities in low-frequency reflection and diffraction – these are the physical properties of sound waves, and they are also the reasons why it is superior to steam cleaning devices. These points will be explained in more detail below. 3) Why can sound waves remove dust? As mentioned earlier, low-frequency sound waves are used for dust removal. Sound waves of this low frequency possess sufficient intensity; in areas where dust and slag accumulate, such as boiler flues, heat exchangers, electrostatic precipitators, and bag filters, these sound waves exert a \"acoustic fatigue\" effect on the dust and slag. Due to the repeated oscillations of the sound waves, cyclic tension and compression forces are applied to the dust and slag, and once a certain number of such cycles occurs, the bonds holding the dust and slag together are broken due to fatigue. At the same time, due to the reflection, transmission, and diffraction of sound waves, regardless of the installation position and direction of the sound source, acoustic energy can reach all corners, gaps in tube arrays, and other relatively hidden small spaces, thereby effectively preventing the accumulation of dust particles. (II) Comparison between acoustic cleaning and steam cleaning technologies (what are the advantages?) As we know, conventional cleaning methods include steam cleaning, hydraulic cleaning, use of steel balls, and high-pressure air – all of which rely on the mechanical force generated by the flow of a medium. Among these, steam cleaning is still the most widely used cleaning technique. 1) Defects of steam soot blowers: (1) There are dead corners in the operating area ； (2) Direct application of high-pressure steam to the heated surfaces causes certain wear and corrosion to the equipment ； (3) Complex structure, high maintenance requirements, and high maintenance costs ； It is also difficult to implement programming, so some companies often refrain from using it ； (4) Due to the limited number of times steam can be directly blown in, usually once every 8 hours, the heated surfaces cannot be kept clean at all times; this not only affects heat transfer but is also detrimental to environmental protection. 2) Acoustic dust cleaner. Due to the inherent properties of sound waves, the sound wave soot cleaning technology essentially overcomes many of the aforementioned drawbacks of steam soot blowers. (1) Excellent dust removal performance, with no dead corners in the effective working area ； (2) Since sound waves are waves, they do not cause any wear or corrosion to the heated surface ； (3) Simple structure, no rotating components, minimal maintenance required, low operating costs ； (4) Due to its simple structure, it is easy to install and operate, and is fully automated ； (5) In particular, since there is no wear or corrosion on the equipment, it can be operated continuously at regular intervals throughout the day. This keeps the heated surfaces clean on a constant basis, thereby improving thermal efficiency and also contributing to environmental protection. (3) A comparison of the main types of sound generation systems used for acoustic dust removal in China: 1) Whistle-type: One of the earlier types developed in China; its audio frequency can be adjusted. However, due to its complex structure and the need for a motor, it suffers from many faults and has poor stability. 2) Hartmann flue type: Since its diameter is located in the dust accumulation area (such as flues), it is constantly subjected to high-temperature corrosion and wear from the flue gases, resulting in a shorter service life ； The nozzles tend to clog, and because audio signals experience rapid energy attenuation at higher volumes with a limited range of action, more units need to be installed under the same conditions. 3) Diaphragm type: The acoustic soot removers produced by the Swedish company Kockums and the American company BHA are both of the diaphragm type. To overcome the disadvantages of the aforementioned two types of acoustic dust removers, our company, backed by technical support from the Chinese Academy of Sciences, improved upon them by drawing on foreign technologies and taking into account the realities of production in China. As a result, we developed the ZHK series of diaphragm-type acoustic dust removers, which practice has shown to be more effective than the imported Swedish IKT230/220 models. This acoustic dust cleaner uses compressed air as the driving medium. When compressed air enters the generator chamber, it causes the diaphragm to vibrate, generating sound waves which are then transmitted through amplification sections and speakers into the area where dust has accumulated, thereby carrying out the dust removal task. This diaphragm-type acoustic soot blower has the following advantages over the other two types of acoustic soot blowers: (1) it delivers high energy, has a long acting radius, and provides excellent performance ； (2) Stable operation, low maintenance requirements, and easy to control ； (3) In particular, it has a simple structure; since the dust remover is made of stainless steel with high temperature resistance and excellent corrosion resistance, its service life is long. The acoustic dust cleaning device manufactured by Zhongke was installed on the bag filters at the Panzhihua Steel Plant in March 2001, and it has been in use for over four years to date. (4) It is easy to inspect and maintain, and the operating and maintenance costs are low. (IV) Conclusion: Some enterprise leaders do not pay enough attention to whether the dust removal system is functioning properly, to common dust accumulation issues, or to the level of exhaust gas temperature; they consider these matters unimportant, which is a sign of a weak awareness of energy conservation. As we all know, power plant boilers are real \"coal tigers\". Coal is produced entirely domestically, and coal used in power plants accounts for a large proportion of it. In power plants, fuel accounts for 70% of the costs; therefore, even a change of just a few tenths of a percent in thermal efficiency can have a significant impact when accumulated over time! One of the main reasons affecting the thermal efficiency of power station boilers is ash accumulation. Empirical analysis shows that boiler ash accumulation affects the boiler’s thermal efficiency by a few tenths of a percent; taking a 300,000-unit capacity boiler as an example, reducing coal consumption by 1 gram can result in annual savings of nearly 1 million yuan. We advise our clients to pay attention to the issue of ash accumulation in boilers. Energy savings can be achieved by focusing on small improvements; we recommend our company’s sonic ash removers as a solution to enhance thermal efficiency and improve environmental conditions. This approach is worthwhile both from an economic and a social perspective! Friends who are interested in learning about this technology can contact me; I have some pictures of our products as well as detailed information available