Abstract: An in-place flush-cleanable mixer system for mixing materials in a vessel. The mixer has an impeller connected to a mixer drive shaft, the impeller and shaft being mounted in an assembly which extends through an opening into the vessel and closes that opening. The assembly has a cylindrical hub with bearings which support the shaft and with an open passageway through which the shaft extends out of an open end of the hub. The open passageway is part of a confinement region which is terminated at its outer end by a confinement shell which separates inner and outer rotors of a magnet coupling. The inner rotor is connected to the mixer shaft, and the outer rotor is connected to a drive shaft. There are no dynamic seals which close the confinement region so that the working materials can be present throughout.

Abstract: In order to circulate a two-phase system (a suspension of solid particles in liquid) in a large (e.g., 100 ft. diameter) and shallow tank (e.g., where the liquid level, Z, to tank diameter, T, ratio is 0.4), a cluster of side entering mixers is used and a desired flow pattern (much like that obtained from a top entering mixer) along the bottom and top of the material in the tank and vertically along the walls of the tank is obtained by (a) rotating an end mixer in the cluster in opposite sense to the other mixers, (b) spacing the mixers so that the interference is reduced between the flow produced by the mixers at the wall of the tank opposite from the mixers, and (c) by tilting the mixers so that the flow intersects the bottom near the wall of the tanks opposite from the mixers.