Ultra High Shear Mixing Technology Since most industrial processes dont take place in a beaker, we must always consider the real-world behavior of high-shear batch mixers in large vessels. Thinking on a molecular level, we ask, ғHow many times does each particle or droplet pass through the high shear zone? Backing up to see the process from a wider perspective, we ask, ԓHow consistent are my results? How uniform is the distribution of particle or droplet sizes in my batch? In many applications these are critical questions because they can profoundly influence the properties of your end product. The daily challenge in high-shear rotor/stator (HSM) mixing is to reach the target droplet or particle size and achieve a satisfactory particle-size distribution in the most cost-effective manner. This requires a careful balance of rotor/stator design, cycle time at a required batch size, capital cost, and per-cycle operating costs. Any batch mixing process ԗ whether the process goal is particle dispersion, particle-size reduction or emulsification generates a Gaussian distribution of results. The greater the ratio of product volume to HSM throughput, the broader the distribution will be. Of course, the goal is usually to produce the narrowest distribution possible with an equipment solution that meets the site-specific process and business requirements. The question is simply, דWhat is the most effective, economical, and practical way to produce the required particle - or droplet size distribution? At mixing equilibrium we have reached the target average particle size. Additional processing will gradually narrow the distribution curve, but extending the process for this purpose alone almost always amounts to a substantial waste of time and energy. An alternative strategy is to increase the size of the HSM. This will increase the ratio of HSM throughput-to-product- volume and narrow the curve. But this will also increase both the initial capital investment and the ongoing energy costs. The attractiveness of this solution depends heavily on the value of the product being manufactured, its competitive strength, and the overall business case for investing heavily in equipment. >

Try a different approach - an ultrahigh-shear mixer The best solution is often to switch to an ultrahigh-shear inline mixer (UHSM). In select applications, an UHSM can achieve the desired process goals in a single pass, allowing this device to process batches of product in a terminalӔ approach (that is, with one single pass of the tank contents through the UHSM, and then on to the next phase of the process). Although the UHSM typically represents a higher capital investment than a traditional single stage HSM, its ability to complete the process in a single pass often allows us to step down to...

Don't assume...test! 25-hp inline mixer with a 4.5-in.-dia. rotor would be an appropriate choice for production. Operating at 3,600 rpm, and with a flow rate of 150 gal/min, this would be a logical choice in most applications. But in this case it was impractical. The 30-minute cycle on the benchtop produced roughly 900 tank turnovers. Projecting to full-scale production in a 2,000-gal.tank, the process would require 7,200 minutes or five days. The best solution proved to be a switch to a UHSM operating at 30 hp with a 6-in.-dia. rotor and a flow rate of 20 gal/min. After the pre-mix, the UHSM...

production before you buy any scaled-up systems. An extra measure of rigor and diligence at this stage can certainly mean the difference between success and failure on the plant floor and profitability in the marketplace Charles Ross & Son Company 710 Old Willets Path Hauppauge, New York 11788 Telephone: 631-234-0500 / Toll Free: 800-243-7677 / Fax: 631-234-0691 Email: [email protected] / website: www.mixers.com >