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BT-6

BT-6
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The unique blade geometry of the BT-6 creates optimal flow conditions above and below the disc to efficiently disperse gas at even the highest flow rate. The BT-6 impeller provides you with state of the art technology in gas dispersion applications. It was developed using the most modern flow measurement techniques and its patented blade geometry efficiently disperses gas at even the highest flow rates. Due to the efficient dispersion mechanism of the BT-6, this impeller can handle more than five times as much gas as the D-6 impeller (Rushton turbine) before flooding, and more than twice as much as Chemineer's concave blade CD-6 impeller (Smith turbine). Another benefit of the BT-6 impeller is a very flat power draw curve under gassed conditions. Since its power draw varies little with gas flow rate, the BT-6 impeller is particularly well suited for applications where gas flow rates change during the process, such as Hydrogenators. Another advantage of the more constant power draw is that changes in mass transfer during the process are smaller than with other impellers. The power draw of the BT-6 shows minimal variation when exposed to changes in liquid viscosity; it remains constant for Reynolds numbers well below one thousand, which corresponds to viscosities of several thousand centipoise in typical industrial applications. The blade design, asymmetric about the plane of the disc, has been optimized to take into account the different flow conditions above and below the disc. The BT-6 impeller's asymmetric design allows the overhang on the top of the blade to capture the rising gas flow. The gas flow is then dispersed from a strong turbulent vortex on the inside of the deep blade. No cavities form on the trailing edges of the blades. In tall tanks the radial pumping BT-6 is used as the primary gas dispersion impeller mounted directly above the gas sparger in the bottom of the tank. Axial flow impellers, such as the wide blade Maxflo W hydrofoil or the narrow blade XE-3 high efficiency impeller, are used as upper impellers. This impeller configuration combines efficient gas dispersion with good overall top to bottom blending. Uniform dissolved gas distribution is achieved throughout the vessel. Our BT-6 impeller offers many advantages over conventional gas dispersion technology: • Greater dispersion capability • Higher rates of interphase mass transfer • Minimal power draw sensitivity to changes in liquid viscosity and gas flow rate • Increased pumping capacity improves blend times and heat transfer BT-6 impellers are available in the normal configuration of six blades with a choice of welded, bolted, or adjustable blades. Standard materials of construction are carbon steel or 316 stainless steel. Fabrications from special alloys are also available. Please contact your local sales representative for assistance with your specific gas dispersion requirements.

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Three Generations of Gas Dispersion Impeller Technology The BT-6 is the leader in gas dispersion impeller technology. For over thirty years the D-6 disc style turbine with flat blades was the primary choice for gas dispersion applications. The CD-6 impeller, which was developed in the late 1980’s, is characterized by its concave blade shape. The CD-6 rapidly established itself as far superior to the D-6 with its capability of dispersing more gas combined with a power draw considerably less sensitive to changes in the gas flow rate. The CD-6 revolutionized the field of gas-liquid agitation...

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