For years, energy in the form of sonic, ultrasonic and megasonic waves has been transmitted into liquid media for purposes such as: to process the liquid media, to inactivate organisms within the liquid media, to enhance chemical reactions (sonochemistry), to degas the liquid media and to clean objects within the liquid media. It is well known that objects may be efficiently cleaned or processed by immersion in a liquid and subsequent application of ultrasonic or megasonic energy to the liquid. It is also well known that liquids can be emulsified, homogenized, mixed and/or degased by application of ultrasonic or megasonic energy to the liquid. Applications such as inactivation of organisms, pasteurization, and sterilization are documented in the ultrasonic literature.
For example, U.S. Pat. No. 7,726,325 is directed to a de-aeration device and ultrasonic cleaning device. International patent application no. WO2008/007631 is directed to a fine bubble generating unit. U.S. Pat. App. No. 2010/0175791 is directed to a super-micro bubble generation device. U.S. Pat. App. No. 2012/0282384 is directed to a fine bubble generating apparatus. The article entitled “Development of Functional Microbubbles for Ultrasound Therapy”, in the Proceedings of the 8th International Symposium on Cavitation, Aug. 13-16, 2012 is directed to a method of creating micro bubbles using shear flow. The article “Microbubble ultrasound contrast agents: a review”, by Stride, et. al., in Proc. Instn Mech. Engrs. Vol. 217, 2003, provides a review of ultrasound contrast agents. The journal article entitled “Potential uses of ultrasound in the biological decontamination of water”, by Mason et al., from the Ultrasonics Sonochemistry (vol. 10 (2003) p. 319-323) discusses using ultrasound to kill bacteria and other microorganisms. U.S. Pat. No. 6,960,173 is directed to an ultrasound wound treatment method and device using standing waves. The article entitled “Inactivation of microbes using ultrasound: a review”, by Piyasena, et al., and published in the International Journal of Food Microbiology (vol. 87 (2003) p. 207-216) discusses juice pasteurization with ultrasound. In the article entitled “A review of research into the uses of low level ultrasound in cancer therapy”, by Yu, et. al., in Ultrasonics Sonochemistry (vol. 11 (2004) p. 95-103), the use of ultrasound is discussed in the treatment of cancer. U.S. Pat. App. No. 2012/0291765 is directed to an apparatus for heating fluids for pre-treating hydraulic fracturing water through passing the fluid through a device with a spinning disk. The discussion of the above references is merely for reference and no assertion is made that the above references are in the same field of the invention or are valid prior art.