History From a revolutionary idea proposed and developed by Dr. Andrew Szegvari in 1945, Attritor technology grew to become the basis for Union Process, Inc., an independent family-owned American company founded in Akron, Ohio. Today, Attritors are considered to be the most efficient grinding/dispersing systems and are used in scores of industries and research laboratories worldwide. How Batch Attritors Work The Attritor is often referred to generically as an “internally agitated high energy media (ball) mill.” The operation of an Attritor is simple and effective. The material to be ground and the grinding media are placed in a stationary, jacketed tank. This media is spheres 3/32" to 3/8" diameter. Commonly used types are carbon steel, stainless steel, chrome steel, tungsten carbide, ceramic, or zirconium oxide. The material and the media are then agitated by a shaft with arms, rotating at high speed. This causes the media to exert both shearing and impact forces on the material, resulting in optimum size reduction and dispersion. No premixing is necessary. The material can be directly fed into the jacketed grinding tank of the Attritor. Those portions of the formulation requiring only slight grinding can be easily added later. Attritors are equipped with specially designed high starting torque, two-speed electric motors. The high starting motor means no clutches, etc. are needed. The lower speed is used for charging and discharging and the high speed is used for grinding. Depending upon the application, electricals can be TEFC (totally enclosed fan cooled) or explosion-proof. Production batch Attritors are equipped with a built-in pumping system that maintains circulation during grinding for accelerated attrition and uniformity. This pump can also be used for material discharging. The final result of the grinding action is a fine, even particle dispersion. Temperature control (either cooling or heating) can be maintained due to the use of jacketed tanks. When high-pressure water, coolant, oil or steam systems are required, ASME- coded tank jackets may be employed. Because grinding action does not take place against the tank walls, wear of the walls is minimal. In addition, thinner walled tanks mean that improved heat transfer can be accomplished. Common Applications/Industries Union Process Batch-Type Production Attritors Produce Fine, Homogeneous Dispersions Quickly and Effectively Special Options TANK LININGS—special linings for metal-free grinding are available. Choose from ceramic (alumina) tiles, food grade rubber or polyurethane. ARM SLEEVES—to accommodate metal-free systems, shaft arms may be sleeved with plastic, tungsten carbide, or zirconium oxide. COVERS—can be equipped with a floating shaft seal to minimize solvent loss, or can be equipped with a MECO shaft seal for grinding under inert gases, complete with a product charging port, gas inlet and outlet. TORQUE METER—for monitoring precise energy consumption which is used for determining grinding time and for added quality control. DRIVES—variable speed drives (either mechanical or electronic) are available for conditions requiring the flexibility of multiple shaft speeds. STATIONARY ARMS—for reducing tank wear SPECIALLY CONFIGURED ARMS—for increased agitation and improved performance visit 2 • Agricultural Flowables • Bagasse • Biofuel/Cellulosic Biomass • Catalysts • Ceramics • Chemicals • Chocolate, Confectionery • Cosmetics • Cryogenic Grinding • DSM (Mechanical Alloying) • Electronic Ceramics • Ferrites • Fibers • Food Products • Glass Frits • Industrial Coatings • Metal Oxides • Metal Powders and Flaking • Minerals, Coal • Paints, toners, inks • Paper Coatings • Pharmaceuticals • Pigments • Proppants • Reaction Milling/ Mechanochemical Milling • Tungsten Carbides