UIP4000hdT – 4 kVt yuqori samarali ultratovush

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Basics of Ultrasonic Homogenization

Ultrasonic homogenizers are used for dispersion, emulsification, wet-milling, nano- & micronization, extraction (from plants and cell tissues), synthesis and catalysis of chemicals (so-called sono-chemistry) as well as degassing. Ultrasonic homogenization is often used as umbrella term that includes all these fore-mentioned applications. The ultrasound-assisted homogenization is based on the working principle of acoustic caviation, which occurs when intense ultrasound waves are coupled into a liquid medium. Under the intense ultrasound waves, minute vacuum bubbles are generated in the medium, which grow over the high pressure / low pressure cycles of the ultrasound waves. At a certain point, when the micro-bubbles have reached an energetic status, at which they cannot absorb more energy, they collapse violently. This phenomenon of vacuum bubble implosion is called cavitation. The implosion of the vacuum bubbles generates shock waves, streaming / liquid jets, high shear, high temperature and pressure differentials with sufficient energy to break covalent bonds, flex molecules and induce chemical reactions.

For best results in the homogenization process, the ultrasonic processor and its setup can be optimized by changing the following variables:

• Amplitude (displacement of the sonotrode) and intensity
• Pressure
• Temperature
• Sonication vessel (batch or flow cell: size, geometry, flow rate)

Hielscher high performance ultrasonic processors use piezoelectric generators made of lead zirconate titanate crystals. The vibrations are transmitted down a titanium horn tuned resonate at 19-26 kHz. From the horn the ultrasonic vibration is coupled via ultrasonic sonotrode (tip, probe) into the fluid medium. Hielscher offers ultrasonic processors with power ratings from 50 to 16,000 watts per ultrasonic unit and covers thereby the requirements from small lab ultrasonicators and bench-top devices up to pilot plant and fully commercial ultrasonic units for high volume throughput.

Sophisticated Process Control for Optimal Sonication Results

Sonication conditions are crucial for output, process results and reproducibility of ultrasonic processes. Besides the precise control of ultrasonic power output, adjusted by amplitude and intensity, temperature, pressure and sonication time are important factors. Hielscher’s digital ultrasonic processors come with a plugable thermo-couple. A plugable pressure sensor is optionally available. Both sensors are connected with the ultrasonic generator, which is equipped with an internal SD card. The software of the ultrasonic device writes all process data (date, time, amplitude, ultrasonic energy, net energy, temperature, pressure) in a CSV file on the SD card. This makes your sonication runs comparable and reproducible.

For high amplitudes, a higher output power is required. Under increased load such as high viscosity of the medium or elevated pressure, an increased ultrasound power is needed to drive the sonotrode at a desired amplitude. The larger the front surface of the sonotrode (tip), the more power is required to let it resonate. With a larger sonotrode, larger volumes can be processed. Hielscher’s industrial sonotrodes and cascatrodes can deliver very high amplitudes. Amplitudes of up to 200µm can be easily continuously run in 24/7 operation. For even higher amplitudes, customized ultrasonic sonotrodes are available. The sturdiness of Hielscher’s ultrasonicators allows for 24/7 operation under heavy load and under demanding conditions.

For most ultrasonic processes, temperature of sonicated medium should be as low as possible for a low temperatures promotes the generation of intense cavitation. Hielscher offers ultrasonic flow cells and reactors with cooling jackets, which support the maintenance of optimal process temperatures. Flow cells and reactores are pressurizable, too. Under elevated pressures, more intense cavitation occurs. Therefore, Hielscher offers reactors that can easily pressurized up to 300atm.

Hielscher Ultrasonics manufactures ultrasonic probes of different sizes and shapes (e.g. cascatrodes), which allows to scale up all ultrasonic process results completely linear. With 16kW ultrasonic homogenizers and manifold types of sonotrodes and flow cell reactors, Hielscher is your long-term experienced partner for ultrasonic processes on industrial scale. Besides the variety of standard ultrasonicators, Hielscher designs and manufactures customized systems, too.