8.4 Conclusion
121
than for hydrodynamic cavitation and requires careful examination of the operating
parameters. Although the roadmap for the intensification of cavitation processes in
the chemical industry has been defined for 20 years by the pioneers in the field, the
road is still long to lead to a generalization of these techniques. However, many efforts
are made to complete the knowledge in the quantification of cavitational collapse
intensity as well as in the development of reactors and the control of operational
parameters. For this purpose, the laboratories are developing numerous semi-pilot or
pilot reactors and much new multidisciplinary collaboration between experimenters
and theoricians.
One of the undeniable contributions of recent years is the continuous progress
of power electronics. Indeed, the control of the ultrasound systems is complex and
nowadays is carried out by digital electronics, which is more efficient and furnishes
better control through sophisticated calculation algorithms. Thus, the quality of the
electronic control is important and aims to stabilize the functioning of the system in
the space and in time. One of the most convincing examples is how to control the
vibration of an axial probe. By setting the operating point exactly to the resonance
of the system, the physics of piezoelectricity shows a direct relationship between
the current supplied by the generator and the displacement at the end of the probe.
Thus, the volume displacement of the fluid located at the end of the probe is constant
whatever the nature of the liquid involved and the power will be the consequence
of the effort to produce to maintain this displacement. This example illustrates that
the control and control strategy of a device can have a major impact on the induced
ultrasound phenomenon and its interpretation.
However, after highlighting the difficulties of dealing with large volumes, we must
keep in mind that scaling can be carried out in an alternative and economical way by
paralleling microfluidic devices.
References
Badve M, Gogate P, Pandit A, Csoka L (2013) Hydrodynamic cavitation as a novel approach for
wastewater treatment in wood finishing industry. Sep Purif Technol 106:15–21
Cao H, Wan M, Qiao Y, Zhang S, Li R (2012) Spatial distribution of sonoluminescence and sonochemiluminescence generated by cavitation bubbles in 1.2 MHz focused ultrasound field. Ultrason
Sonochem 19:257–263
Carpenter J, Badve M, Rajoriya S, George S, Saharan VK, Pandit AB (2016) Hydrodynamic cavitation: an emerging technology for the intensification of various chemical and physical processes
in a chemical process industry. Rev Chem Eng 33:433–470
Casadonte DJ Jr, Flores M, Petrier C (2005) Enhancing sonochemical activity in aqueous media
using power-modulated pulsed ultrasound: an initial study. Ultrason Sonochem 12:147–152
Cintas P, Mantegna S, Calcio Gaudino E, Cravotto G (2010) A new pilot flow reactor for highintensity ultrasound irradiation. Application to the synthesis of biodiesel. Ultrason Sonochem
17:985–989
Crudo D, Bosco V, Cavaglià G, Grillo G, Mantegna S, Cravotto G (2016) Process intensification
in biodiesel production with a rotor-stator type generator of hydrodynamic cavitation. Ultrason
Sonochem 33:220–225
121
than for hydrodynamic cavitation and requires careful examination of the operating
parameters. Although the roadmap for the intensification of cavitation processes in
the chemical industry has been defined for 20 years by the pioneers in the field, the
road is still long to lead to a generalization of these techniques. However, many efforts
are made to complete the knowledge in the quantification of cavitational collapse
intensity as well as in the development of reactors and the control of operational
parameters. For this purpose, the laboratories are developing numerous semi-pilot or
pilot reactors and much new multidisciplinary collaboration between experimenters
and theoricians.
One of the undeniable contributions of recent years is the continuous progress
of power electronics. Indeed, the control of the ultrasound systems is complex and
nowadays is carried out by digital electronics, which is more efficient and furnishes
better control through sophisticated calculation algorithms. Thus, the quality of the
electronic control is important and aims to stabilize the functioning of the system in
the space and in time. One of the most convincing examples is how to control the
vibration of an axial probe. By setting the operating point exactly to the resonance
of the system, the physics of piezoelectricity shows a direct relationship between
the current supplied by the generator and the displacement at the end of the probe.
Thus, the volume displacement of the fluid located at the end of the probe is constant
whatever the nature of the liquid involved and the power will be the consequence
of the effort to produce to maintain this displacement. This example illustrates that
the control and control strategy of a device can have a major impact on the induced
ultrasound phenomenon and its interpretation.
However, after highlighting the difficulties of dealing with large volumes, we must
keep in mind that scaling can be carried out in an alternative and economical way by
paralleling microfluidic devices.
References
Badve M, Gogate P, Pandit A, Csoka L (2013) Hydrodynamic cavitation as a novel approach for
wastewater treatment in wood finishing industry. Sep Purif Technol 106:15–21
Cao H, Wan M, Qiao Y, Zhang S, Li R (2012) Spatial distribution of sonoluminescence and sonochemiluminescence generated by cavitation bubbles in 1.2 MHz focused ultrasound field. Ultrason
Sonochem 19:257–263
Carpenter J, Badve M, Rajoriya S, George S, Saharan VK, Pandit AB (2016) Hydrodynamic cavitation: an emerging technology for the intensification of various chemical and physical processes
in a chemical process industry. Rev Chem Eng 33:433–470
Casadonte DJ Jr, Flores M, Petrier C (2005) Enhancing sonochemical activity in aqueous media
using power-modulated pulsed ultrasound: an initial study. Ultrason Sonochem 12:147–152
Cintas P, Mantegna S, Calcio Gaudino E, Cravotto G (2010) A new pilot flow reactor for highintensity ultrasound irradiation. Application to the synthesis of biodiesel. Ultrason Sonochem
17:985–989
Crudo D, Bosco V, Cavaglià G, Grillo G, Mantegna S, Cravotto G (2016) Process intensification
in biodiesel production with a rotor-stator type generator of hydrodynamic cavitation. Ultrason
Sonochem 33:220–225