Homogenizers are mixers and are emulsifiers when used with certain substances. Of course, not all mixers are homogenizers. The terms mixers and blenders are sometimes used interchangeably; according to some definitions, however, blenders have sharper blades and operate at higher speeds than mixers.
Emulsification may occur, depending on the product; that is, solids or liquids that are usually unable to mix are blending together thoroughly. Homogenizers have been used for a number of years in many industries, including science and technology, food processing and in some industrial mixing processes. Common products that are homogenized include milk and cream or oil and water.
During the process of homogenization, the high shear mixer is immersed in the materials. The high speed rotation of the blades creates suction that draws the solid and liquid portions of the mix into the work head, where the blades are.
Centrifugal force drives the materials out the work head and through the blades, where they are finely milled and evenly dispersed. This process is done in circulation until all of the solid material has been blended and mixed evenly with the liquid, which creates a new substance with a new viscosity and appearance.
Mechanical homogenizers fall under two categories: rotor-stator homogenizers and blade type homogenizers. In a rotor-stator homogenizer, material is drawn into the mixing apparatus by a rapidly moving rotor positioned within a motionless tube containing slots or holes. Once there, the material is thrown through the slots/holes at a very high speed. This process is repeated many times, resulting in the mixing of the material.
Blade homogenizers use cutting blades which rotate at 6000 to 50000 rpm. These blades, by cutting and blending, completely mix the material within the homogenizer. The latest technology in homogenizers focuses not only on mixing material evenly, but also on preventing cross-contamination, infection control and noise produced by the machine.