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Static Mixing Technology STATIC MIXING TECHNOLOGY PRODUCT INNOVATION Since 1965, in thousands of installations worldwide, Kenics® Static Mixers have set the standard for in-line mixing and heat transfer performance. Chemineer incorporates advanced technology into every Kenics Mixer to give you reliable, uninterrupted performance that you can depend on for the long term. The result: maximum operating efficiency and overall cost savings. PRINCI P LE S OF OP ERATION In the KM Static Mixer, a patented helical mixing element directs the flow of material radially toward the pipe walls and back to the center. Additional velocity reversal and flow division result from combining alter- KM Static Mixer nating right- and left-hand elements, increasing mixing efficiency. All material is continuously and com- Front Side view pletely mixed, eliminating radial view gradients in temperature, velocity and material composition. HEV Static Mixer In the HEV and UltraTab Static mixing elements. The element easily reproduced and reliably scaled. Mixers, the element geometry maxi- geometry takes advantage of the Numerous independent studies have mizes the conversion of turbulent naturally occurring vortices induced shown Kenics Static Mixers maximize energy into efficient mixing. The by the element edges. mixing efficiency—without the wasted HEV and UltraTab produce complete energy and material blockage stream uniformity through controlled These mixing principles result in an typically found in more restrictive vortex structures generated by the applications technology that can be motionless mixers. 2 MIXING App LICATION S Kenics Static Mixers provide precise blending and dispersion of all flowable materials, without utilizing moving parts. Mixing is achieved by redirecting the flow Turbulent Blending Turbulent Blending patterns already present in empty HEV and UltraTab Static Mixers KM Static Mixer pipe. Kenics Static Mixers are Each tab of the HEV Static Mixer The KM Static Mixer produces currently being used in numerous generates a pair of streamwise rapid mixing by inducing circular processing applications, in order counter-rotating vortices, while the patterns that reverse direction at to reduce overall cost and signifi- UltraTab, with upstream injector, each element intersection. cantly improve efficiency, speed provides rapid incorporation of and control. Kenics Static Mixers additives. Both mixers produce can be found in a wide range of vigorous cross-stream mixing and rapid uniformity. markets including chemical, refining, polymer, food, pulp and paper, and water and waste- water treatment. These high efficiency mixers also handle other critical processes, such as: Heating/Cooling Kenics Mixers dramatically boost Laminar Blending Laminar Blending heat transfer rates over those KM Static Mixer KMX-V Static Mixer typically found in open pipe The alternating helical elements The intersecting blades of the under both laminar and turbulent of the KM Static Mixer continually KMX-V mixer create cross-stream flow conditions. divide, stretch and reorient the mixing and flow splitting to flow stream to produce complete achieve rapid mixing even in the Residence Time Control mixing with minimum pressure most demanding applications drop. such as those with extreme By eliminating the parabolic viscosity and volume ratios. velocity profile characteristic of laminar flow in open pipes, the helical element of Kenics Mixers promotes plug flow in continuous processes. Temperature Uniformity The radial mixing action of the KM elements rapidly eliminates Liquid/Liquid Gas/Liquid temperature gradients, reducing Dispersion Dispersion fouling and thermal degradation. The uniform turbulent shear field Gases can be incorporated into of the KM Mixer quickly disperses turbulent liquids using the KM immiscible liquids and produces a Static Mixer. Mass transfer rates narrow drop size distribution. are dramatically enhanced to maximize absorption or reaction. 3 KM SERIE S STATIC MIXER S Kenics KM Series Static Mixers feature a patented helical mixing element which produces complete radial mixing and flow division for any combination of liquids, gases, Element Assembly — KMA or solids. • Mixing elements are inserted in the customer’s existing housing Adapts to Any Piping System • Precisely controlled to assure proper fit and ease of installation in any Mixer dimensions match all stan- Fixed Element — KMS standard or custom pipe size dard pipe sizes. Mixer housings • Used for laminar, transitional, feature plain, threaded, weld prep and turbulent flow applications; or flanged ends for easy installa- suitable for most blending or tion. Flange styles include raised dispersion problems involving face slip-ons, weld neck, lap joint, liquids or gases ring joint and Grayloc-type hubs in all standard pressure ratings. • Mixing elements are attached to Mixers are available in carbon the housing wall steel, 304SS, 304LSS, 316SS, 316LSS, Alloy 20 Cb-3, Titanium, Monel 400, Nickel 200, Inconel, Hastelloy C-276, Hastelloy B-2, Edge-Sealed Element — KME FRP, PVC, CPVC, PTFE, Kynar, • Used for maximum heat transfer, PVDF, Tantalum, Zirconium and polymer reactors, certain fibrous other high alloys. applications, and mixing liquids with wide viscosity ratios • Mixing element edges are furnace- brazed to the housing wall eliminating dead areas • Continuous joining of elements to Removable Element — KMR the housing eliminates wall clear- • Used for laminar, transitional, ance to maximize heat conduction and turbulent flow applications and minimize thermal degradation where periodic cleaning or or fouling inspection is required; suitable • Available with internal surface for most blending or dispersion finishes down to 8 microinches problems involving liquids or gases Construction options include: • Mixing elements are easily • ASME/B31.3 certification and testing removed from housing • Design pressures to over 10,000 psi • Jackets, nozzles, fittings • Complete custom fabrication • Diameters to over 8 feet 4 HEV & ULTRA TAB STATIC MIXER S HEV high-efficiency static mixers handle all turbulent-flow mixing applications regardless of line size or shape. Mixing is accomplished by controlled vortex structures generated by the patented low- profile tab geometry.This provides uniform blending while limiting mixer length to less than 1-1/2 pipe diameters. Complete mixing is achieved with pressure losses 75% less than conventional static mixers. Typical applications for the HEV include all low-viscosity liquid-liquid blending processes, as well as gas- gas mixing. The HEV is ideal for processes where pressure loss and length are critical. HEV Static Mixer features include: • Lowest pressure drop available • Unlimited sizes and shapes • Shortest possible mixer length • Easy retrofit to existing lines UltraTab • Available in all metals and alloys, The UltraTab provides rapid FRP, PVC, PFA, and epoxy- mixing in circular pipe turbulent coated steel flow applications. The integral • Low cost, wafer design is available injector allows upstream injection for installation between flanges of additives to produce a 0.05 CoV (coefficient of variation) in as little HEV static mixers provide installa- as two pipe diameters downstream tion flexibility and can be configured from the exit of the mixer. The to square, rectangular or 3-sided compact tab design minimizes ducts. They are adaptable to open the length required for mixing channels typically found in water and optimizes piping layout. treatment systems. 5 KMX-V STATIC MIXER S The Kenics KMX-V Static Static Mixer Comparison, Viscosity Ratio = 53,000:1 Mixer is the 1.0000 choice for demanding mixing applications, such as those involving 0 fluids with extreme 0.1000 viscosity or volume ratios. The COV/COV common limiting factor in static 0.0100 0 2 4 6 8 10 12 14 mixer design is L/D the allowable mixer length and the patented element design offers a KMX-V Mixer with Concave Blades short length and the most efficient Static Mixer with Flat Blades mixing performance. EXCLU S IVE MIXING PRINCI P LE The KMX-V utilizes cross-stream mixing and flow splitting to achieve very rapid blending. Each element is approximately one pipe diameter in length and consists of multiple intersecting blades, which gener- ate fluid layers as the mixture flows KMX-V-4 KMX-V-8 KMX-V-12 downstream. Laser induced fluorescence (LIF) images showing cross-sectional uniformity KMX-V Mixer features include: • Superior mixing performance • Laminar flow and high-low Sheets of low viscosity viscosity mixing additives are driven along • Liquid dispersion/gas-liquid the trough of each blade contacting and abruptly sheared • Cost effective solution by strong cross-stream velocity gradients as they • Short length pass around the upstream • Standard diameters up to 24" surface. 6 TECHNOLOGY App LICATION Guaranteed Mixing Uniformity 0.100 1000 The standard technique used for 2 Others measuring the degree of mixing 0.010 100 P HEV-4 in pipe flow is the coefficient of 0.001 10 D=150mm CoV / CoVo SG=1.0 variation, CoV. The coefficient of 1 Kenics µ=1.0 cP .0001 1 variation is the ratio of the standard 1000 10 000 100 000 1 000 000 10 50 100 Re Q deviation of component concentra- tion to its mean concentration. The Mixing Uniformity Pressure Drop coefficient of variation achieved at By analyzing the inlet stream The pressure drop through Kenics the mixer discharge is dependent conditions, final mixture quality Static Mixers is the lowest in the on the inlet coefficient of variation can be predicted for all Kenics industry
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