What Is Ultrasonic Degassing?

Ultrasonic degassing essentially utilizes the "cavitation effect" generated when ultrasound waves propagate through a liquid to strip, aggregate, and expel gases from the liquid. Its core process can be divided into three key stages:

 

The first stage is the formation of cavitation bubbles. When ultrasound waves (typically between 20kHz and 1MHz) act on a liquid, the liquid molecules vibrate violently under the periodic pressure changes of the sound waves. In the negative pressure phase of the sound waves, tiny pores within the liquid (such as clusters of dissolved gas molecules or gaps on the surface of tiny impurities) rapidly expand, forming numerous tiny bubbles, or "cavitation bubbles." In the positive pressure phase, these cavitation bubbles are rapidly compressed.

 

The second stage is the growth and merging of bubbles. Under the continuous action of ultrasound waves, cavitation bubbles continuously absorb dissolved gases from the surrounding liquid. Simultaneously, adjacent small bubbles collide and merge under the drive of the sound waves, gradually forming larger bubbles. During this process, the gas dissolved in the liquid continuously transfers from the liquid phase to the gaseous phase, realizing the transformation from "dissolved gas" to "free gas."

 

The third stage is the rising and expulsion of bubbles. As the bubble volume increases, its buoyancy gradually exceeds the viscous resistance of the liquid, causing the bubble to rise rapidly to the liquid surface, eventually bursting and releasing its internal gas, thus completing the degassing process. Furthermore, ultrasonic vibrations can accelerate liquid convection, further promoting bubble migration and aggregation, and improving degassing efficiency.

Main application areas of ultrasonic degassing technology

 

1. Electronics and Semiconductor Industry

In semiconductor chip manufacturing and LCD panel production, tiny air bubbles in key chemicals such as photoresist, etching solution, and developer can cause defects in photolithographic patterns and uneven etching, severely impacting product yield. Ultrasonic degassing can quickly remove dissolved gases and air bubbles from these chemicals at room temperature, ensuring the precision of photolithography and etching processes. Furthermore, in the cleaning of electronic components, ultrasonic degassing enhances the penetration of cleaning solutions, preventing air bubbles from adhering to component surfaces and affecting cleaning effectiveness.

2. Chemical and Materials Industry

 

In the production of coatings, inks, and adhesives, the presence of air bubbles can lead to defects such as pinholes, craters, and insufficient gloss after coating. Ultrasonic degassing can quickly remove internal air bubbles after coating preparation, improving the leveling and application performance of the coating. In the synthesis of polymer materials, dissolved gases in monomers or polymerization systems can cause pores within the polymer, affecting the material's mechanical properties; ultrasonic degassing effectively avoids this problem. Furthermore, in the production and use of lubricating oil and hydraulic oil, ultrasonic degassing can remove air from the oil, preventing oxidation and deterioration, and reducing equipment wear and malfunctions.

3. Food and Beverage Industry

In the production of fruit juice, beer, carbonated beverages (degassing stage), and dairy products, dissolved gases can cause product oxidation and deterioration, resulting in poor taste, or foam overflow during bottling. Ultrasonic degassing can quickly remove oxygen, carbon dioxide, and other gases from liquids at room temperature, extending product shelf life and improving taste stability. For example, in the fruit juice concentration process, degassing can prevent the concentrate from discoloring and changing flavor due to oxidation; in the pre-filtration stage of beer production, degassing can improve filtration efficiency and ensure beer clarity.

4. Biopharmaceutical and Cosmetic Industry

Materials such as biological agents (e.g., vaccines, antibodies, enzyme preparations), traditional Chinese medicine extracts, and cosmetics (e.g., face creams, serums) are mostly heat-sensitive and easily oxidized, making traditional degassing methods difficult to adapt. Ultrasonic degassing can efficiently remove gas under low-temperature, chemical-free conditions, preventing material denaturation and ensuring the product's biological activity and efficacy. For example, in vaccine production, degassing prevents air bubbles from affecting the accuracy and stability of vaccine dispensing; in cosmetics production, degassing avoids foaming during product use, improving the user experience.

5. Laboratory and Research Fields

In chemical and biological experiments, dissolved gases in the reaction system can interfere with the reaction process and affect the accuracy of experimental results. Ultrasonic degassing, as a rapid and gentle degassing method, is widely used in the pretreatment of experimental solutions, such as degassing chromatographic analysis samples and degassing electrolytes in electrochemical experiments, ensuring the reliability of experimental data.