Packed Tower Internals - NTNU

1 Packed Tower InternalsKoch-Glitsch s dedication to providestate-of-the-art mass transfer equip-ment is demonstrated in a completeline of Packed Tower Internals , devel-oped through extensive testing andyears of experience with mass transferequipment, such asINTALOX HighPerformance Distribution Systems. Byunderstanding the important role of liq-uid and vapor distribution, Koch-Glitschcan confidently design Packed columnsto provide predictable Packed Tower Systems com-bine INTALOX high performance liquidand vapor distribution with high perform-ance packings such as:- FLEXIPAC ,FLEXIPAC HC ,INTALOX or Wire Gauze Structured Packings - IMTP orSNOWFLAKE High Performance Random Packing- CASCADE MINI RINGS or -ETA RING Random PackingsFor information regarding Koch-Glitsch randomand structured packings, please ask forbrochures KGRP-1, KGIMTP-1 and flow testing is used to confirmthe performance of INTALOX liquid dis-tributors.

2 Computational Fluid Dynamics(CFD) analysis is available for verificationof vapor distribution designs. Ask yourKoch-Glitsch representative about theseoptional recognizes that not allpacked towers require state-of-the-artliquid distribution uniformity. Koch-Glitsch offers a wide range of traditionalstyle Internals , used over many years inless demanding services. This brochuredescribes the importance of liquid andvapor distribution and the circumstancesin which INTALOX Packed TowerSystems should be the years, Koch EngineeringCompany, Inc., now Koch-Glitsch, hasdeveloped and acquired proven internalsand technology for Packed columns fromGlitsch and Saint-Gobain NorPro. As aresult of these acquisitions, Koch-Glitschhas identified and now offers the bestproducts and technology from each com-pany. Because of these changes, productmodel designations have also column Internals models listed in thisbrochure represent the majority of rec-ommended column Internals for course, exact replacements of any column internal formerly sold by Koch,Glitsch or Norton (NorPro) are availableupon request and can be supplied, designedand built to their original sions of many of the Internals describedin this catalog are also available in a varietyof FRP and thermoplastic materials.

3 For infor-mation regarding these products, please askfor brochure Type and Description Old NorPro Old Koch Old Glitsch PageModelModel model ModelLiquid DistributorsINTALOX High Performance Liquid Distributors 106 Pan distributor1067116 Deck distributor1168126 Channel distributor with bottom orifices1263208136 Channel distributor with drip tubes1363219141 Tubular distributor 330 POH-921 10156 Trough distributor with enhanced baffle plates312 NTD-72110186 Trough distributor with drip tubes186311 TNT-72711 INTALOX High Performance Liquid Redistributors 107 Pan redistributor1077117 Deck redistributor with bottom orifices1178127 Channel redistributor with bottom orifices1278137 Channel redistributor with drip tubes1379 Traditional Performance Liquid Distributors905 Pan distributor with V-notch risers 798306

4 NRD-65112906 Pan distributor with bottom orifices845 DRO-60112916 Deck distributor with bottom orifices816, 916301 A,B,D RTD-551- 55413926 Channel distributor with bottom orifices101613976 Trough distributor with bottom orifices14985 Trough distributor with weirs806310, 302 VND-701,71114986 Trough distributor drip tubesTNT-72715996 Trough distributor with drip point multipliersTNS 34 Traditional Performance Liquid Redistributors917 Deck redistributor with bottom orifice 817, 917 301 A,B,DRTD-552-554 13927 Channel redistributor with bottom orifice1017 301 A,B,DRTD-552-55413 Enclosed Channel and Pressure Fed Liquid Distributors941 Pipe-arm distributor with orifices844342, 304 POH-901 16943 Spray nozzle distributor1044344, 305 SNH-951-X16961 Enclosed channel distributor for offshore applications87417Ta bl e of Contents1 Packed Tower Internals Guide2 Device Type and Description Old NorPro Old Koch Old Glitsch PageModelModel model ModelFeed DevicesLiquid Feed Devices18119 INTALOX High Performance Liquid Only Feed Pipe119, 12934019719 Liquid only feed pipe719, 72919 Mixed Liquid/Vapor and Flash Feed Devices705 Flashing feed chamber85520745 Flashing feed pipe655300 RFD-56120755 Flashing or mixed phase feed gallery755341 RFD-57121758 Enhanced vapor horn192360.

5 361 VDA-99222765 Suppressed flashing feed distributor14434788 Enhanced V-baffle vapor inlet diffuser350 VDV-99421798 Vapor inlet for FCC Main Fractionators34 Vapor Feed and Distribution Devices716 Deck type vapor distributor 896 CTD-53123746 Lateral arm vapor distributor198342 VDP-99123748 Vapor diffuser19624768 EVENFLOW Vane Type Vapor Distributor19435124 Liquid Collectors611 Deck style liquid collector833501 CTD-50125613 Deck style liquid collector for offshore application34621 Trough style liquid collector733500 CTD-52125622 Trough style liquid collector for fouling services34633 Chevron vane liquid collector633510, 51126 Packing Bed Limiters27803 Structured packing bed limiter, non-interfering133403 HDG-42127805 Random packing bed limiter, non-interfering103401 BLM-46128815 Anti-migration screen between different packing sizes11134825 Random packing bed limiter823 BLM-45128845 Bed limiter used in combination with spray distributors82234883 Structured packing bed limiter/liquid distributor support 29 Packing Support Plates30802 SStructured packing support grid134102 HPS-12130804 Random packing gas injection support plate804101 RUTS-20131814 Random packing gas injection support plate, small diameter818101 UTS-21831824 Light duty random packing support plate809103 UTS-20932 General Details and Other TopicsConstruction details33 Special Tower internals343 Liquid DistributionLiquid Distribution Liquid distributors are used in packedcolumns above each bed of distributor, depending upon itsdesign features, is elevated between 0 to 8 in.

6 [0-200mm] above the space is determined by the distribu-tor type and the vertical height requiredto disengage the vapor phase from thepacking before it flows through the dis-tributor gas passage ideal distributor possesses the fol-lowing attributes, each having a specificeffect on the overall performance of thepacked Tower : Uniform liquid distribution Proper operation through its turn-down range Low vapor phase pressure drop Resistance to plugging or fouling Optimal use of vessel height for proper performance Minimal liquid residence time Mixing capability for redistribution to the next bedThe introduction of high performancetower packings in the 1970 s and 1980 saccentuated the design deficiencies ofdistributors available at the time. Inresponse, Koch-Glitsch introduced dis-tributors with features to correct thesedeficiencies. These important featuresare well understood by Koch-Glitsch andhave been incorporated in the family ofINTALOX high performance offers two categories of liquid distributors to meet the require-ments of specific applications.

7 In deter- mining which category to choose, it isnecessary to know the sensitivity of theprocess and whether the liquid distribu-tion will significantly affect the overalltower a general rule: Koch-Glitsch INTALOX high perform-ance distributors are used typically with FLEXIPAC, FLEXIPAC HC,INTALOX and wire gauze structured packings or IMTP, SNOWFLAKE,CMR and -ETA RING high perform-ance random packings in the following services: distillation, processes approaching equilibrium or heat-trans-fer applications with close approach temperature. Koch-Glitsch traditional distributors are generally used with traditional packings (FLEXIRING and HY-PAK Random Packings, plastic Super INTALOX Saddles,FLEXIGRID and GLITSCH GRID Structured Packings) in general absorption, strip-ping and heat transfer distributors take advantage of standardized, pre-engineered design and the optimal use of raw distributors do not generally provide liquid flow uniformity compa-rable to INTALOX high performance always, there are exceptions to thegeneral rules.

8 High performance packing may be used with traditional distributors in cases when only certain aspects of a high performance packing are desired. An example would be to take advantage of the high capacity of IMTP packing or the low pressure drop of FLEXIPAC HC structured packing, when the separation efficiencydemands are not high. Traditional packing may be used with high performance distributors in cases when a process is licensed and speci-fied with a certain type of decision of when to install morethan one Packed bed and redistribute theliquid is somewhat more involved. Thereare six major reasons to split a packedbed and redistribute the liquid: Feed introduction Product side draw High theoretical stage count Desire to cross-mix the liquid Liquid maldistribution Physical weight of the Packed bedIntroduction of a liquid or vapor feed toa column requires a space in the packingand redistribution of the liquid factors to keep in mind withthe introduction of a liquid feed are thetemperature and composition of the feedstream compared to the internal columnliquid.

9 Normally, unless the feed rate issmall compared to the flow rate of theinternal column liquid, it is desirable tomix the feed with the internal liquid toprovide compositional uniformity beforedistributing it to the Packed bed is also advisable to mix the feedstream and internal liquid when theirtemperatures are significantly degree of the thoroughness of themixing depends upon the magnitude ofthe differences and to what extent thegradients are expected to affect theoverall cross-mixing and maldistributioncorrection often go hand-in-hand. Whena Packed column is designed with a largenumber of theoretical stages or transferunits, a constant liquid to vapor ratio(L/V) is needed to achieve the best over-all column performance. Redistributionof the liquid ensures that the L/V ratio ismaintained, while cross-mixing betweenbeds ensures uniform on Koch-Glitsch s operating expe-rience, a rule-of-thumb is to limit a singlepacked bed to no more than 20 theoreti-cal stages or transfer units.

10 Consult aKoch-Glitsch technical representative forfurther details. Note that in some spe-cial circumstances, Koch-Glitsch appliesmore restrictive rules than those dis-cussed liquid distribution is defined asproviding equal liquid per unit area of thepacked bed surface. Theoretically thiswould require an infinite number of liquidstreams,all at identical flow. This is clearlyimpossible. A number of factors such asorifice size, fouling potential and mechani-cal construction limit the ability to makethe "perfect" distributor. INTALOX highperformance distributors approach perfec-tion by applying the following criteria: Drip points located in a uniformpattern Drip point positions uninterrupted by vapor chimneys or mechanical supports Drip points properly spaced with respect to the vessel wall Minimal variation in flow between drip pointsKoch-Glitsch "traditional" distributorshave less uniform distribution patternsand liquid flow than the INTALOX highperformance distributors.