Sulzer Chemtech. Internals for packed columns

Transcription

1 Sulzer Chemtech Internals for packed columns

2 Table of contents Page Introduction 2 Column types 3 Liquid distributors 4 Selection of liquid distributors 4 Splash-plate distributor VEP 5 Channel-type distributors VKG and VKR 6 7 Collector / distributor VS 8 Distributors for corrosive media 9 10 Distributors for further applications Distributor hole size 14 Liquid collectors Support and locating systems 17 Gas / Liquid inlet systems Introduction This brochure provides an overview of Sulzer Chemtech Column Internals, which have be developed in Sulzer Chemtech s extensive test facility and used in commercial applications for many years. The following pages will provide you with detailed information on our internals for structured and random packings. At Sulzer Chemtech, decades of design, construction and manufacturing experience are combined with on-going development and state-of-the-art production methods to guarantee you products of the highest possible quality. In order to comply with your specific requirements, our sales engineers and specialists will always be ready to discuss detail inquiries with you personally. We look forward to working with you to develop a customized packed tower solution that will exceed your expectations. 2

3 Internals for packed columns Column type When preparing column internals specifications, you must know whether you will be using a flanged column or a welded vessel. If your column is a welded vessel, then you must know the inside diameter of the manhole. Prior to beginning engineering of your column and internals, Sulzer Chemtech will verify with you the overall column height, and the manhole inside diameter Flanged columns Packings and internals are installed through the column flange. Welded vessel columns Packing and segmental internals are installed through manholes. 3

4 Liquid distributors Selection of liquid distributors For every process application, Sulzer Chemtech can offer you a solution fitted to your own particular needs. When selecting the optimal distributor, professional advice from Sulzer Chemtech s specialists is always valuable. Our decades of experience and well-founded expertise make your distributor selection decisions easy. Peak performance of your column is achievable only if you precisely match your column internals to both your packings and their specific process application. The following chart shows a choice of Sulzer Chemtech distributors to match your own particular liquid loading and column size. Sulzer Chemtech specialists will help you select just the right liquid distributor for your process application. 200 Collector/distributor, VS Specific liquid load (m 3 /m 2 h) 50 : Channel-type distributor, VKG Channel-type distributor VKG1) VKR1) High-liquid load distributor, VKH/VEH Splash-plate distributor, VEP Splash-plate distributor, VEPW Low-liquid load distributor, VKRPW 1 ) fi Midget load distributor VEPK Column diameter (m) 1) Can be supplied in a flanged version, also for diameters > 0,8 m These distributors are suitable for most applications. For very difficult applications, Sulzer Chemtech can provide customdesigned distributors that will fit your specific requirements. 4

5 Liquid distributors Splash-plate distributor VEP The splash-plate distributor VEP is Sulzer Chemtech s most widely used distributor. Its patented discharge system has several advantages: Fewer lateral holes, due to the spreading effect of the splash-plate. Larger hole diameters than conventional discharge systems. Anti-plugging, due to large holes and the lateral discharge of liquid. The feed liquid is pre-distributed at a precisely controlled rate from a main channel (mounted above) into the individual arm channels Splash-plate distributor VEPW For low liquid flow rates, the special splash-plate distributor VEPW is used to accommodate liquid loads as low as 0.1 m 3 /m 2 h. Low pressure drop and no entrainment up to F 4.5 Pa 0.5 Discharge system VEP Specifications Diameter Liquid load > 0.8 m 0.5 to 30 m 3 /m 2 h VEPW: 0.1 to 1.0 m 3 /m 2 h Drip-point density 40 to 200 drip points per m 2 Turndown ratio 3:1 max. Gas load F-factor up to 4.5 Pa 1/2 Sensitivity to contamination Construction details Special note Slight Can be levelled by a device supported on the packing If required, this distributor can be constructed as a self-supporting unit (e.g. for use with random packings) 5

6 Liquid distributors Channel-type distributor with bottom holes VKG The channel-type distributor VKG has been successfullly used for many years in columns up to 2 m diameter. It is one piece distributor with integral channels attached, suitable for installation through a removable head of a vessel. A segmental version can be installed through a manhole in larger vessels. The liquid is fed into a large center channel, then distributed through holes in the individual channel bottom onto the packing. The VKG distributor is not recommended at low liquid loads when suspended solids are present Discharge system VKG Specifications Diameter Liquid load 0.25 to 2.0 m; flanged design above 0.8 m 1 to 100 m 3 /m 2 h Drip-point density 40 to 200 drip points per m 2 Turndown ratio 3:1 max. Gas load F-factor up to 4.5 Pa 1/2 Sensitivity to contamination Construction details Special note At low liquid loads Can be levelled by means of locating or suspension device In addition, a pre-distribution system is used at high liquid loads and larger column diameters 6

7 Liquid distributors Channel-type distributor with lateral tubes VKR The channel-type distributor VKR resembles the distributor VKG except that it uses tubes at the side of the channels rather than holes in the channel bottom to distribute the liquid onto the packing. This feature makes the distributor VKR less susceptible to plugging. The multiple-stage version is able to handle broad liquid loading ranges, up to 10:1. The range of liquid loading must be carefully considered when designing a distributor VKR Low-liquid load distributor VKRPW For extremely low-liquid loads, the special channel distributor VKR- PW is used to accommodate liquid loads as low as 0.05 m 3 /m 2 h. Its has a supplemental liquid distribution system beneath each tube to distribute extremely low liquid volume evenly to the packing VKR Discharge system VKRPW Specifications Diameter > 0.25 m Liquid load 1 to 20 m 3 /m 2 h for VKR; 0.05 to 1 m 3 /m 2 h for VKRPW Drip-point density 40 to 200 drip points per m 2 Turndown ratio 3:1 max.; multiple-stage distributor, 10:1 Gas load F-factor up to 5 Pa 1/2 for VKR; up to 3.5 for Pa 1/2 for VKRPW Sensitivity to contamination Slight Construction details Can be levelled by means of locating or suspension device Special note The low-liquid load distributor is constructed in diameters up to 4 m 7

8 Liquid distributors Collector / distributor VS The collector/distributor VS is used whenever collection and redistribution of liquid is required at very high liquid loads. It resembles a chimney tray; however the chimney arrangement is custom designed for your application s liquid distribution and pressure drop requirements. For moderate liquid loads applications, where liquid mixing is important, a separate accumulator tray must collect the liquid and feed it to a liquid distributor located below it Specifications Diameter Liquid load m >30 m 3 /m 2 h Drip-point density 40 to 160 drip points per m 2 Turndown ratio 3:1 max. Gas load F-factor up to 3 Pa 1/2 Sensitivity to contamination Construction details Special note Slight Tray construction, bolted and supported on ring with chimney types corresponding to hydraulic requirements Truss supports are used in large column diameters 8

9 Liquid distributors for corrosive media Plastic distributor The bottom-hole distributor VEG and the channel-type distributor VKR are available in PP, PVDF, PVC, and other plastic materials. The maximum operating temperature is 60 to 100 o C depending on plastic material Specifications Diameter Liquid load m 1-20 m 3 /m 2 h Drip-point density 80 to 200 drip points per m 2 Turndown ratio 3:1 max.; multiple-stage, 10:1 Gas load F-factor up to 4.5 Pa 1/2 Sensitivity to contamination Slight for VKR Construction details Supported on the packing Graphite distributor VSTG The one-piece distributor VSTG is constructed of graphite for use in highly corrosive environments. It uses tubes with lateral outlets to distribute the liquid onto the packing. It is installed in flanged column only. Graphite distributors VSTG can be used to collect and redistribute liquids between packed sections Specifications Diameter m Liquid load 1 to 20 m 3 /m 2 h Drip-point density 40 to 160 drip points per m 2 Turndown ratio 3:1 max., multiple-stage, 10:1 Gas load F-factor up to 3 Pa 1/2 Sensitivity to contamination Slight Construction details Supported on the packing 9

10 Liquid distributors for corrosive media Glass distributor VRGG The distributor VRGG is made of glass for use in small columns. The patented closed tube discharge system has special outlets on the underside of the distribution tubes to distribute the liquid onto the packing. It is a one-piece distributor that can be installed through a column flange by following the prescribed installation procedures Specifications Diameter m Liquid load 1 to 20 m 3 /m 2 h Drip-point density 40 to 200 drip points per m 2 Turndown ratio 3:1 max. Gas load F-factor up to 4.5 Pa 1/2 Sensitivity to contamination High Construction details Supported on the packing 10

11 Liquid distributors for further applications Spray nozzle distributor VRD The spray nozzle distributor VRD is specially designed for and used in refinery and scrubber columns. Proper spray nozzle selection is crucial to the operation of your columns. Sulzer Chemtech specialists will help you chose from a variety of fullcone, axial, and tangential nozzles to customize your spray patterns to your specific application s requirements Midget load distributor VEPK This distributor is applied for very low liquid loads < 100 l/m 2 h The orifices are placed in sidewalls to allow catching of sinking dirt High-liquid load distributor VKH/VEH The distributor VKH is used for high liquid loads, e.g. greater than 20 m 3 /m 2 h. This is an excellent nonplugging distributor. The liquid is discharged laterally from rectangular channels onto the packing

12 Liquid distributors for further applications Bottom-hole distributor VEG The distributor VEG resembles the widely used splash-plate distributor VEP. The difference is that the li quid is discharged through holes in the channel bottoms rather than laterally against a vertical baffle. It is not recommended for liquids containing solids Lateral distributor VER The liquid is discharged laterally and guided by conducting elements to the packing surface. The distributor allows high vapor loads F > 5 Pa 1/ Tube distributor VRG The distributor is non sensitive on moving conditions like columns operated off shore or on vessels. Liquid is discharged from the underside of the tubes. This distributor is not suited for liquids containing solids or contamination

13 Liquid distributors for further applications Extraction distributor VRX The distributor VRX is a two-stage distributor for use in packed liquidliquid extraction columns. Its special design, specific for continuous and dispersed phase, prevents emulsions from occurring, even when surface tensions are low Radial distributor VFS The distributor VFS was developed and especially designed for emulsions and liquids with high solids contents. It uses open, radial channels with deflector plates to direct the liquid onto the packing. The distributor is a cost efficient solution for applications where somewhat increased liquid maldis-tribution can be tolerated Slotted distributor VES The distributor VES is used to distribute liquids containing catalyst residues. It uses open channels with lateral slots and deflector plates to distribute the liquid

14 Liquid distributors Outlet hole sizes in distributor channels The following table enables the determination of approximate distributor channel hole sizes at normal liquid loadings. The hole size can be roughly determined in relation to the liquid load and the required drip-point density. The choice of drip-point density must be made in accordance with the specific surface area of the packing used. Exact hole sizes will be determined by Sulzer Chemtech s specialists after all necessary parameters have been defined. In this way your distributor will be con-figured to match your application and achieve optimal hydraulic conditions. VEP splash-plate Drip point density (VD) figures consider the distribution effect of the splash-plate. hole size (mm) L (m 3 /m 2 h) VD 80 VD 160 VD 200 VD 330 Hole sizes in other distributors hole size (mm) L (m 3 /m 2 h) Distributor test rig All Sulzer Chemtech liquid distributor configurations are routinely performance tested in Sulzer Chemtech s liquid distributor test rig prior to delivery. Minimum and maximum flow rates measurements are always performed. Surface area measurements are possible, with the detection of standard deviations Distributor test rig

15 Liquid collectors Vane collector SL The collector SL is used as a separate unit to accumulate liquids from packed sections within a column. This collector requires a ring channel welded to the column wall. The pressure drop of this collector is negligible Collector support grid SLT The collector SLT combines a packing support grid with a vane collector. As a packing support, it can support the direct load of packings with surface areas up to 350 m 2 /m 3. For finer packings, additional drip plates are used. This non-welded collector SLT is often used in applications where space between packed beds is critical. This collector requires a support ring inside the column Collector SLF The collector SLF is designed to be installed between the column flanges in smaller flanged columns

16 Liquid collectors Chimney tray collector SK The collector SK is an established and versatile accumulator tray design, available either as bolted or sealwelded construction. It is generally used in large diameter columns with high liquid loads Pressure drop is a function of the type and configuration of the chimneys. Sulzer Chemtech specialists can design your collector SK to your process specifications. Whether you need a total draw-off, a flash tray, a gas distribution device, or a unique chimney configuration, the collector SK can be custom designed to meet your specific application needs

17 Support and locating systems Support grids TEB / TSB TEB and TSB are used with structured packings. Both require support rings to be welded to the column wall. TEB s are grids for flanged columns. The segmental grids of the TSB pass through manholes and are clamped together for convenient installation. The grid is a non welded construction. TEB and TSB support grids are ideal for applications requiring expensive alloys. Certain high performance packings require additional drip plates. Support grids TE / TS TE and TS are intended for structured packings with surface area over 350 m 2 /m 3 packing volume. They are designed with drip plates to prevent premature flooding of the packing. These support grids rest on support rings or gussets welded to the column shell. For columns over 3 m ID, additional supports and major beams may be required. Random packing support grid GIS / EMS GIS and EMS are used with random packings and serve as gas injection trays to distribute the gas to bottom layers of the packing. Both grids have an open cross sectional area of 0%, GIS and EMS differ only in their overall height. EMS is used in small column up to 1.2 m diameter. GIS is used in larger diameter columns. Retaining grid for random packings RPB Retaining grids, consisting of wire mesh welded to the underside of grid frames, are required above random packing beds. Such grids may be either suspended from a liquid distributor above it or bolted to a support ring welded to the column wall

18 Gas inlet systems Gas inlet systems When preparing column specifications, the method of feeding the column, drawing off liquids, and removing gases must not be over-looked. They are as important as selecting of the optimum packing and matching it to the proper internals to get peak performance from your packed column. Owing to years of experience and continuous development at Sulzer Chemtech, we are always in a position to offer you both standard gas inlet systems and specialty tailored solutions based on CFD studies GITV Cyclon inlet GD Open inlet CFD-simulations to analyse and improve vapour distribution GIG Tube inlet GDP Splash plate inlet GIV Vane inlet

19 Liquid inlet systems Liquid inlet systems LV inlet 100% liquid feeds to small diameter columns LRR inlet Super-heated liquid feeds LV (2) inlet % liquid feeds to larger diameter columns LRP inlet Liquid feeds containing gases

20 Please check for your local contact Sulzer Chemtech Ltd, a member of the Sulzer Corporation, with headquarters in Winterthur, Switzerland, is active in the field of process engineering and employs some 4000 persons worldwide. Sulzer Chemtech is represented in all important industrial countries and sets standards in the field of mass transfer and static mixing with its advanced and economical solutions. The activity program comprises: Process components such as fractionation trays, structured and random packings, liquid and gas distributors, gas-liquid separators, and internals for separation columns Engineering services for separation and reaction technology such as conceptual process design, feasibilities studies, plant optimizations including process validation in the test center Recovery of virtually any solvents used by the pharmaceutical and chemical industry, or difficult separations requiring the combination of special technologies, such as thin film/short-path evaporation, distillation under high vacuum, liquid-liquid extraction, membrane technology or crystallization. Complete separation process plants, in particular modular plants (skids) Advanced polymerization technology for the production of PLA and EPS Tower field services performing tray and packing installation, tower maintenance, welding, and plant turnaround projects Mixing and reaction technology with static mixers Cartridge-based metering, mixing and dispensing systems, and disposable mixers for reactive multi-component material Distributed by: V Printed in Switzerland Legal Notice: The information contained in this publication is believed to be accurate and reliable, but is not to be construed as implying any warranty or guarantee of performance. Sulzer Chemtech waives any liability and indemnity for effects resulting from its application.