Improving on a Good Thing: The Chemineer Xe-3 High-Efficiency Impeller
Eric E. Janz, Chemineer, Inc., P.O. Box 1123, Dayton, OH 45401, Julian B. Fasano, Mixer Engineering Company, 2673 Stonebridge Drive, Troy, OH 45373, and Kevin J. Myers, University of Dayton, 300 College Park, Dayton, OH 45469-3433.
The introduction of low-power number axial-flow impellers revolutionized the design of agitators for flow-controlled processes such as blending, heat transfer, and solids suspension. These impellers were capable of meeting process objectives at lower torque and power levels than traditional pitched-blade turbines. The Chemineer HE-3 is an example of a first generation high-efficiency impeller that has found numerous applications in the chemical processing and allied industries. Building upon the success of the HE-3, a new high-efficiency impeller, the XE-3, has been designed to further improve impeller performance, both in terms of mechanical characteristics and process performance. By virtue of their shape, the blades of the XE-3 are stronger than those of the HE-3, thus reducing the weight of the impeller. This provides a number of benefits, including lower material costs and the possibility of using higher speeds, and thus lower torques, and/or longer shafts. Although these mechanical improvements are quite positive, obtaining them at the cost of reduced process performance would not be acceptable. Thus, the XE-3 is designed to provide higher pumping efficiencies and improved solids suspension performance than other high-efficiency impellers. This presentation will describe how the XE-3 simultaneously improves mechanical and process performance, including comparisons of the pumping efficiency and solids suspension performance of the XE-3, HE-3, and pitched-blade impellers.