Hielscher Cascatrode – High Surface Sonication Probe
Hielscher developed the Cascatrode™ for industrial processing applications. Cascatrodes™ are available for all industrial ultrasonic processors – from UIP500hdT (0.5kW), UIP1000hdT (1kW), UIP1500hdT (1.5kW) and UIP2000hdT (2kW) up to the world’s most powerful ultrasonic device UIP16000 (16kW).
When developing or testing new sonication processes, such as: emulsifying, dispersing, homogenizing, cell disruption and extraction, deagglomeration, or degassing you will find that specific sonication parameters work for the process better than others. Without changing the output power you can vary the sonication intensity: Either focus the power output on small surface at high intensity (high W/cm²) or couple the power into the medium using a large surface area at lower intensities (low W/cm²). The intensity increases with higher sonication amplitude, higher liquid pressure or higher viscosity and decreases with higher temperature. Once, you established an optimal parameter configuration for you process, you will need to keep this configuration constant during scale up. When scaling up, you should not change the amplitude and pressure of sonication. This way, you keep the sonication intensity – this is the ultrasonic power output per surface unit (Watts/cm²) constant. As a logical result, you need more sonotrode surface area to couple more power at a given surface intensity – this is a linear correlation.
Hielscher offers a wide range of sonotrodes (=sonication probes) for its ultrasonic devices. Commonly, the sonotrodes vary by tip diameter to provide different tip surface areas. The vertical surfaces of a sonotrode are generally negligible for power transmission, as their oscillation amplitude directed to the liquid medium is very low. The Cascatrode™ design is different, as it adds ring shaped horizontal surfaces to the tip surface. Each ring is arranged in one of the oscillation maximums of the sonotrode. By these rings, the vibrating surface that couples the ultrasound into the medium to be sonicated can be increased, significantly – allowing for higher ultrasonic power to be coupled into the liquid at a given surface intensity. The Cascatrode™ makes it possible to transmit high ultrasonic power at high amplitudes into the processed medium.
The Hielscher Cascatrodes™ are available in various lengths and diameters and with various numbers of rings – designed to match the process intensity and the specific ultrasonic application. As they are used for high power and high volume processes, the Cascatrodes™ are mostly installed into continuous flow-through systems. They are adaptable with flow cell reactors that allows for efficient inline processing at industrial scale.