Liquid Mixing and Agitation Equipment

What is Liquid Mixing and Agitation?

Where in the mixing process would you find Sterimixers and Sterivalves?

• Storage: the liquid is kept in constant movement in order to keep two or more different liquids mixed in a constant concentration and temperature throughout the vessel. For example, a typical low-shear biopharmaceutical application in storage tanks, buffer and media hold.
• Heat transfer: the liquid needs to be constantly moving in order to achieve a constant temperature in heated (jacketed) vessels.
• Mixing miscible liquids: the pumping action of the mixer combines the liquids with the objective being the creation of a homogeneous composition in the tank. Higher pumping rates will speed up mixing but might produce more shear and the formation of an undesirable vortex. A balance between mixing time and acceptable shear/vortex is required.
• Dissolving solids in liquid: similar to mixing miscible liquids, the pumping action helps to dissolve and keep the ingredients in a liquid state. Solids that are hard to incorporate often require a higher degree of shear and the ability to form a vortex.
• Suspensions: solids are kept in suspension in a liquid phase. Low shear mixers are typically used. The amount of transferred power required depends on the particle settling speed and the degree of suspension that is desired (e.g. off-the-bottom or uniform suspension).
• Dissolving gas in liquid: this is common in bioreactors where air is introduced and the mixer helps disperse the bubbles in order to increase oxygen transfer. The degree of shear is related to the oxygen transfer rates required by the application.