Structured packing
ETCO Pack Wire Mesh Column Packing
Introduction
- ETCOPACK WM COLUMN PACKING was developed by ETCOGREEN as part of a comprehensive development program to improve column packing performance.
- The ETCOPACK COLUMN PACKING is constructed with innovative textured wire gauze layers. This special gauze (which is normally made of metal) provides a high degree of wicking, drawing the liquid in all directions into a thin film and thus providing a marked improvement in uniform wetting of the packing bed.
- The wire gauze layers are corrugated in a novel contoured pattern and arranged vertically in close contact to form modules. These modules are then stacked with an alternating 90-degree orientation of ETCO in the other layer, which gives a good lateral distribution of liquid and gas.
Performance
The capillary action and high surface area provide maximum exposure between the liquid and vapour phases, thus providing a very high mass transfer efficiency.
We design and manufacture various internals to help maximize tower performance. Good initial distribution, together with systematic redistribution, is critical to tower performance. ETCOPACKWM packing is available in the ETCOPACKWMX 500 WW 750 high-efficiency version.
Special features of this packing include
- High number of theoretical stages per unit height. (Between 3 and 8 theoretical stages per meter of packed height).
- Pressure drop per theoretical stage: 0.I-I.0 mbar.
- Can operate at a minimum liquid load of 0.05 m³/m²/h (approx.)
Applications
Because of their low pressure drop and minimum hold-up characteristics, ETCOPACK is an ideal mass transfer medium for temperature-sensitive systems. These include vacuum distillation, temperature-sensitive compounds, low-liquid loading systems, speciality chemicals, isomer separation, essential oils and fragrances, organic intermediates, amines, glycols, fatty acids, fatty alcohols, plastic monomers, vitamins and pharmaceuticals. Wire gauze packing has a limited suitability for fouling services and applications involving non-wetting liquids.
ETCO Pack Sheet Metal Column Packing
Introduction
- ETCOPACKSM COLUMN PACKING is the sheet metal version of the popular ETCOPACKWM (wire mesh) PACKING. ETCOPACKSM is supplied in modules which consist of parallel layers of uniquely designed embossed sheet metal strips which are corrugated and arranged vertically.
- These modules are then stocked at an alternating 90-degree orientation with respect to ETCO’s other layer, which results in good lateral distribution of liquids and gases. The embossed metal strips help to draw the liquid in all directions into a thin film and provides a marked improvement in uniform wetting of the packing bed.
- With the improved internal liquid distribution, high volumetric moss transfer efficiency is achieved and low pressure drop is maintained. Also, because the liquid is evenly distributed through the packing as a thin film, the total liquid hold-up in the packing is substantially reduced.
- The standard packing version has a specific surface area of 250 m²/m³ (ETCOPACKSMY 250). ETCO and other variants with specific surface areas of 125 m²/m³ (SMY 125), 175 m²/m³ (SMY 175), 350 m²/m³ (SMY 350), 500 m²/m³ (SMY 500), 750 m²/m³ (SMY 750), and X crimp (60-degree crimp alignment) are also available.
Performance
ETCOPACKSM series of packing displays excellent performance characteristics. For example, ETCOPACK SMY 250 provides
- Up to 3 theoretical stages per meter of pocked heights in the normal operating range and up to 4 stages at low gas loads.
- Large operating range with high separation efficiency up to high F factors.
- LOW specific pressure drop (below 1 mbar per theoretical image)
Performance curves for ETCOPACK SMY 250 as well as the other packing versions are available upon request. Special features of these packing include
- Can be used for increasing capacity of existing tray or packed columns.
- Pressure drop per theoretical stage: 0.3-0.1 mbar
- Can operate at minimum liquid load of 0.2 m³/m²h (approx)
High performance versions of ETCOPACK SMIY 25S/45S/75S are also available now with a 20% lower pressure drop and the same efficiency as their generic versions.
Applications
Vacuum Distillation: Where a relatively low pressure drop is critical to maintaining low bottom temperatures so as to reduce product degradation.
Atmospheric Distillation: Where a large number of theoretical stages ore required and/or where there are restrictions to overall column height.
Debottlenecking/energy reduction programs: With the advantage of a high efficiency pocking used to reduce reflux requirements and increase throughputs.
Increase product purity: This is possible due to the availability of more equilibrium stages when compared to a similarly sized column.
ETCO Pack Laboratory Packing
For laboratory and pilot plant/small capacity applications, high efficiency distillation packing’s are offered by ETCO.
These include:
A. HYFLUX
High efficiency knitted wire mesh packing belongs to the Goodloe/Hyperfil/Knitmesh family. When a moderate to large number of theoretical stages have to be accommodated within limited tower height, HYFLUX provides a high mass transfer rate (and hence maximum separation efficiency) because the fine wire or filament from which it is made provides a contact surface area in the range of 1200-2000 m²/m³ with a free volume between 94% and 97%.
B. ETCOPACK WMXD & WMXE
High-efficiency wire gauze packing’s module finds special applications for services where a large number of theoretical stages are required in a limited headroom, such as in a laboratory or pilot facility. These can be used to provide a preliminary assessment of a separation task and also to derive reliable scale-up data. ETCOPACKWMKE is a more efficient version than the WMKD but with a lower capacity factor.
ETCO Grid Packing
ETCO Rings Random Packing
ETCO SEP Column Internals
Introduction
As the oil & gas and chemical processing industry matures, a new class of high-efficiency tower internals ore required. AS a result of its in-house design and engineering capabilities, as well as its working relationship With various end users, ETCO has developed a comprehensive range of high-efficiency tower internals.
However, for high-efficiency columns (such as wire gauze structured packing and new random packing), we offer a range of compatible high-performance column internals. An optimum combination of tower internals and column packing’s can be offered to meet the requirements of our customers.
We can provide close to perfect initial liquid distribution along with matching liquid collectors/redistributors and other associated column internals. The following column internals are widely used to obtain optimum performance of designed system
- Packing support and retainer grid.
- Liquid distributor.
- Liquid collector / Re-distributor.
- Chimney Trays.
1. Packing Support & Retainer Grid
Packed beds must be supported within the column with a compatible support grid; these should be mechanically strong enough to support the dead weight of the packed bed along with the liquid hold-up in the column. Packing support grids should also be sufficiently open so as not to restrict the flow of vapour and liquid but also close enough to hold the packing (especially for random picking).
A packing retainer grid is also recommended as a good engineering practice at the top of each packed bed to restrict movement off the bed. It will also ensure that the top of the packing remains level during service.
2. Liquid Distributor
Liquid distribution is a critical factor in consistently maximizing mass transfer efficiency from a packed bed. One of the basic functions of a liquid distribution system is to reduce the horizontal inertia of the liquid at the inlet nozzle/orifice and redirect the flow downwards over the top of the packing such that the complete packing cross section receives the liquid at a uniform irrigation rate. The entire surface area of the pocking must be irrigated to promote vapor/liquid.
Various distributor designs and configurations are available to cater to specific requirements of high numbers of drip point locations, wide turndown ranges, and moderate fouling services. High-efficiency liquid distributors are equipped with level adjustment mechanisms so that levelness tolerances necessary to ensure design performance can be achieved on-site.
3. Liquid Collectors/ Re-Distributor
Where the moss transfer duty requires a total packed height that exceeds the efficient design of a single bed, two or more separate beds should be The of the liquid collector/ re-distributors to collect all the liquid draining from the bottom of one bed, mix the collected liquid to blend out composition variations and to redistribute the liquid over the second bed so that the complete packing cross section receives c uniform irrigation rate.
The complete distribution system must be sufficiently open so as to avoid excessive restriction of the gas flow, leaving the packed bed, which may in turn lead to gas misdistribution or high velocities resulting in re-entrainment of the feed liquid. These devices can be of a collector cum distributor design (with a chimney tray) and these are used for high liquid load application. Alternatively, one can use a vane type design, especially for vacuum and low liquid load service.
4. Chimney Trays
Chimney trays consist of a liquid collection deck and gas risers or chimneys designed to allow gas flow to bypass the tray. The collected liquid can either be drown from a side draw nozzle in the vessel or it can be channelled to a location below the tray (and in some cases both).
