Up to 35% Reduction in Production Cost

Integrating ADV® Pinnacle Performance Trays and other AMT advanced mass transfer equipment has achieved production cost reductions of up to 35% in PTA producers, BTX recovery from pyrolysis gasoline, and ethanol anhydride production.

This is achieved through a combination of improved separation efficiency, reduced energy consumption, and elimination of unnecessary chemical additives — particularly in extractive distillation applications.

What Is a Cartridge Tray?

Pre-Assembled Tray Bundles

A cartridge tray is not a single tray but a complete, pre-assembled bundle of trays and downcomers held together on a tie-rod framework. Each bundle — the "cartridge" — is fabricated and inspected in the shop, then shipped as a rigid unit ready for installation.

Because small-diameter columns cannot accommodate a manhole, there is no way for a worker to climb inside and bolt trays onto welded support rings the way they would in a large tower. Instead, the cartridge bundle is lowered into the column through its body (girth) flanges. Successive bundles bolt together as they are installed, and the assembled stack rests on support clips welded to the shell, with each tray sealed against the column wall by a circumferential gasket.

A typical bundle carries on the order of eight to ten trays. The tray decks themselves can be any standard type — sieve, valve, or bubble-cap — so the separation performance of a full-size trayed column can be reproduced inside a column only a few hundred millimetres across.

A single AMT cartridge tray unit — tray deck, integral envelope downcomer, and gasketed outer shell.

A full AMT cartridge bundle — multiple trays stacked and locked on tie-rods, ready to lower into the column.

Feed & Distribution

• Inlet diffusers
• Feed distributors
• Vapor distributors
• Liquid distributors

Quench & Mixing

• Quench decks
• Quench mixing boxes
• Inter-bed distributors
• Collector trays

Support & Retention

• Catalyst support grids
• Hold-down screens
• Outlet collectors
• Catalyst media

Controlled Liquid Distribution

The truncated downcomer geometry provides precision liquid distribution to each active bubbling area — controlled by the tray design, not by fabrication or installation quality. Equal L/V on every pass, every time.

VCFC Elimination

By achieving equal L/V distribution across all passes, ADV-TDD® eliminates Vapor Cross Flow Channeling — the dominant failure mode in large multi-pass columns that can reduce efficiency by 30–50 percentage points.

Increased Active Area

The truncated downcomer geometry provides additional bubbling area compared to conventional downcomers — simultaneously improving both throughput capacity and mass transfer efficiency without increasing column diameter.

C3 / C2 Super-Fractionation

C3 splitters, C2 splitters, and other close-boiling super-fractionation columns where high tray count and high reflux demand maximum efficiency from every tray.

Aromatics Plants

Raffinate columns, benzene columns, extract columns, and reformate splitters in BTX and aromatics production — new and revamp applications.

Other Super-Fractionations

C4, C5 olefin separation, paraxylene columns, LNG absorbers, regenerators, and other high liquid loading applications where conventional multi-pass trays underperform.

Lower Capital Cost

One column, one condenser, one reboiler, and one set of pumps and instruments replaces two of everything — directly reducing installed capital cost by 25–35%.

Lower Energy Use

The thermodynamic efficiency of separating three components in a single column with a dividing wall is inherently superior to two sequential columns, reducing energy consumption by 25–35%.

Reduced Plot Area

A single column occupies a fraction of the plot area of two separate columns with their associated equipment — a significant advantage for plant revamps and space-constrained grassroots projects.

Reduced Thermal Degradation

Shorter residence time at elevated temperatures — particularly relevant for thermally sensitive products in pharmaceutical, fine chemical, and specialty chemical applications.

Revamp Capability

Existing columns can be revamped to DWC configuration to increase capacity, improve product purities and yields, or add a third product stream — without replacing the column shell.

Three Pure Products

Produce three (or more) high-purity product streams — light product from the top, intermediate product as a side draw, and heavy product from the bottom — from a single column.

Case Study 1: Intermediate Component Separation

An existing chemical plant production line used one column with 100 trays (2.6m diameter) to separate intermediate components, with chronic product quality issues — visible impurities in the main HR product — that could not be resolved even under higher top reflux. Heat exchangers were regularly blocked, causing unexpected shutdowns.

Zehua/AMT proposed a DWC design using a 3m diameter column with 10m of structured packing plus 59 trays. The new design processed the same 110 tph feed while eliminating the impurity problem entirely.

Case Study 2: BTX Separation with DWC

A refinery modified its reform unit and added an extraction unit to recover benzene, toluene, and xylenes (BTX) from reformate. The conventional process required two columns to separate BTX. Zehua/AMT designed a DWC with AMT ADV® high-performance trays — a 3.4m diameter column with 100 trays — producing four high-purity product streams from one column.

The column was successfully started up and all product purities came within specification from first operation.

"The Great Divide" — January 2021

Jason Lyu & Fred Tahmassi, AMT International Inc., USA

Tieyong Liu, Beijing Zehua Chemical Engineering Co. Ltd, China

Evaluates different applications for dividing wall columns with two commercial case studies demonstrating 24–26% energy reduction, complete elimination of product impurities, and full purity specification achievement from first startup.

"Distillation-tray downcomer design improves mass transfer efficiency"

Joint Development: AMT International, Inc. (Plano, TX) & Petronas (Kuala Lumpur, Malaysia) · Chementator section, page 17

Featured in Chemical Engineering's Chementator section following AMT's presentation at the AIChE Spring 2010 meeting. The article describes how AMT's Downcomer Distributor technology — developed through a joint research program with Petronas — eliminates stagnant and retrograde liquid flow patterns on distillation trays by creating directional flow within the downcomer itself. In testing, the technology consistently produced 5–10% greater tray efficiency compared to conventional downcomer configurations. Applied commercially at several Petronas plants beginning in 2008, achieving +24% efficiency in LPG columns and +29% in depropanizers.

"An Innovation in Advanced Mass Transfer Technology: The Combination of a High Performance Tray and a Novel Downcomer Distributor for Optimal Performance"

Authors: Lindsey Vuong, Kuang Wu, Adam Lee (AMT International, Inc.); Zainab Bt. Kayat (Petronas Group Technology Solutions); Amy A. Yusof (Petronas Gas Berhad) · San Antonio, TX, March 24, 2010

Full technical paper presenting the theory, experimental validation, and commercial results of the AMT Downcomer Distributor technology. Includes dye injection flow pattern experiments in 1.2m and 5.2m diameter simulators, oxygen desorption tray efficiency measurements at multiple weir loadings, and complete before/after performance data from the Petronas GPP6 commercial application — LPG column tray efficiency 63%→77% (+24%) and Depropanizer 77%→97% (+29%), with C3 production increased by 2.3 MTon/hr and C4 by 4.2 MTon/hr.

"Successful implementation of a new extractive-distillation technology for aromatics recovery"

Co-authored with LG Chem, Ltd. · Edited by Gerald Ondrey · Chemical Engineering Chementator, September 2013, page 11

Reports the successful conversion of LG Chem's sulfolane liquid-liquid extraction (LLE) unit at Yeosu, Korea to AMT's AED-BTX® extractive distillation process. The converted unit achieved all revamp objectives: over 35% savings in energy, over 12% increase in production (limited by feedstock availability, not column capacity), on-specification raffinate, benzene and toluene purities and recoveries from first startup in April 2013. Capital return on investment expected in under 12 months. The conversion reused existing equipment, columns, and the original sulfolane solvent without modification.

"Advanced Aromatics Recovery Technology with AED-BTX Process"

Authors: Ciputra Jap, Jeffrey Chiu, Kuang Wu (AMT International, Inc.); Sung-Chul Yoo (LG Chem, Ltd., Yeosu, Korea); Tzong-Bin Lin, Jyh-Haur Hwang (CPC Corporation, Taipei, Taiwan) · Austin, TX, April 28, 2015

Comprehensive technical paper co-authored by AMT, LG Chem, and CPC Corporation presenting the full AED-BTX® Process history, development, commercial application, and financial results. Covers the joint R&D program begun in 2005, the CPC Corporation pilot demonstration in Taiwan (10,000 BPD pygas LLE to ED conversion), and the full LG Chem Yeosu commercial application with complete Performance Test Run data. Results: 35–38% steam savings (extended to 45–48% with slight relaxation of raffinate benzene spec), 11%+ throughput increase, benzene purity 99.95 wt%, toluene purity 99.45 wt%, sulfolane in products <1 ppm, payback period <6 months. 8 granted + 6 pending patents worldwide.

"The Great Divide"

Authors: Jason Lyu & Fred Tahmassi, AMT International Inc., USA · Tieyong Liu, Beijing Zehua Chemical Engineering Co. Ltd, China

This article evaluates different commercial applications for dividing wall column (DWC) technology — the energy-saving distillation technology that separates three or more components in a single column with 25–35% lower capital cost and 25–35% lower energy consumption than conventional two-column sequences. Two detailed commercial case studies are presented: intermediate component separation in a chemical plant achieving −24% energy consumption and complete elimination of product impurities, and BTX separation in a refinery achieving −26% steam consumption with all product purities meeting specification from first startup. Zehua/AMT had completed 19 commercial DWC installations by the time of publication.

2019 Technical Article

Authors: AMT International Inc. Engineering Team

AMT's 2019 publication in Hydrocarbon Engineering covers the ADV-TDD® (Truncated Downcomer Distributor) 3rd generation multi-pass tray technology and its application to large-diameter PDH unit C3 splitters. The article details how conventional 6-pass tray designs routinely fail to achieve design efficiency (40–65% actual vs. 90%+ design) due to uncontrolled liquid maldistribution and Vapor Cross Flow Channeling, and presents AMT's engineered solution. Contact AMT for full article access.

AMT Contributes to Industry Knowledge

AMT's engineers regularly present at industry conferences and contribute technical articles to leading publications. If you are an EPC contractor or plant owner interested in AMT's technical expertise, contact us to request copies of published articles or to discuss a technical presentation for your engineering team.

Asia Pacific

Sinopec, PetroChina, CNOOC, Formosa Plastics, CPC Corporation Taiwan, China Steel, CAPCO, PETRONAS, LG Chem — AMT's largest client concentration is across China, Taiwan, South Korea, and Southeast Asia.

Middle East & Europe

EQUATE (Kuwait), CEPSA (Spain), Petronor (Spain/Repsol), BASF (Germany) — AMT has a strong presence in both the Middle Eastern petrochemical and European refining sectors.

North America & Global

BP, NOVA Chemicals, Indorama Ventures, CHS — global majors and leading North American chemical producers have relied on AMT's products for both new builds and revamp projects.

Greater Tray Efficiency

Consistently higher than conventional segmental and multichordal downcomers under normal tray operating conditions — at all weir loadings tested (4, 6, and 8 gpm per inch).

All Flow Rates Tested

Across 120, 180, and 240 gpm tests in the 1.2m simulator, the DD ranked first for liquid flow pattern quality at every condition — water only and air/water systems.

No Pressure Drop Penalty

Segmental DC, multichordal DC, and Downcomer Distributor all exhibited very similar pressure drop characteristics — efficiency gains come at zero pressure drop cost.

Chemical Engineering Magazine — May 2010 & AIChE Spring Meeting 2010

Chemical Engineering (May 2010): "Distillation-tray downcomer design improves mass transfer efficiency" — Chementator feature on AMT/Petronas joint development
AIChE 2010: "An Innovation in Advanced Mass Transfer Technology: The Combination of a High Performance Tray and a Novel Downcomer Distributor" — Lindsey Vuong, Kuang Wu, Adam Lee (AMT); Zainab Bt. Kayat, Amy A. Yusof (Petronas)

1. Standard Sulfolane — No Special Solvent

AED-BTX® uses the original Sulfolane as the extractive distillation solvent — no proprietary solvent or additives required. Sulfolane's excellent selectivity, thermal stability, availability, and low cost apply equally to the ED process. Existing solvent inventory can be reused directly.

2. Effective Three-Phase (L+L+V) Fractionation

AMT's proprietary process and mass transfer equipment design enables effective three-phase fractionation in the ED column — achieving optimized vapor-liquid-liquid contact that reduces solvent circulation rate and energy consumption simultaneously.

3. Heavy Hydrocarbon Control in Lean Solvent

A proprietary process scheme and equipment design controls heavy hydrocarbon accumulation in the lean solvent — a critical issue that limited earlier ED implementations. This maintains optimum solvent performance and extends run times.

4. Full-Range Feedstock Capability

Effective BTX recovery directly from full-range (C6–C8) reformate or pygas feedstock — without pre-cutting C8+ components. Applicable to benzene-only, benzene/toluene, and full BTX (C6–C8) aromatics recovery applications.

Financial Benefits — Minimum Capital, Maximum Returns

Chemical Engineering (Sept 2013) & AIChE Spring Meeting (2015)

Chemical Engineering, September 2013: "Successful implementation of a new extractive-distillation technology for aromatics recovery" — co-authored with LG Chem, edited by Gerald Ondrey
AIChE Spring Meeting, April 2015: "Advanced Aromatics Recovery Technology with AED-BTX Process" — co-authored by Ciputra Jap, Jeffrey Chiu, Kuang Wu (AMT); Sung-Chul Yoo (LG Chem); Tzong-Bin Lin, Jyh-Haur Hwang (CPC Corporation)

Design from Process Data

Provide AMT with your process conditions — flow rates, operating pressure, temperature, fluid properties, and separation requirements — and our engineers will select and size the optimal separator internal combination for your service.

Own-Brand Product Supply

AMT supplies separator internals under our own product line — including the MPV Vane Pack, Z-Pack De-Entraining Device, Agglomeration Device, and AMT Mist Eliminators — engineered and fabricated to our quality standards.

Replacement Supply

AMT can supply direct replacement separator internals based on existing drawings or dimensions — ideal for turnaround projects where like-for-like replacement with a reliable supplier is the priority.

Feed Distributor

The Feed Distributor is the first internal a mixed-phase feed encounters inside a separator vessel. It performs the initial and most critical task — dissipating the high inlet momentum of the incoming stream, initiating the primary separation of gas from liquid, and distributing the flow uniformly across the vessel cross-section for effective downstream separation.

AMT's feed distributor uses a vane geometry that redirects the incoming two-phase or three-phase stream, causes the heavy liquid phase to drop out by gravity and centrifugal action, and allows the gas phase to distribute uniformly into the separation space above. This primary separation step significantly reduces the liquid loading on downstream mist elimination internals.

Swirl Tubes

Swirl tubes use centrifugal force to achieve high-efficiency gas-liquid separation in a compact footprint. The incoming gas-liquid stream passes through a set of fixed swirl vanes that impart a spinning motion to the flow — the heavier liquid phase is thrown outward to the tube wall by centrifugal force, where it drains downward and out through the liquid outlet, while the cleaned gas exits through the top.

AMT supplies swirl tubes in banks of multiple tubes for high gas throughput applications. They are effective in both vertical and horizontal separators and are particularly suited to compressor suction scrubbers, inlet separators, and gas processing applications where high liquid loading and compact vessel size are both requirements.

MPV Vane Pack

The AMT MPV Vane Pack is a high-capacity mist eliminator assembly designed specifically for horizontal or vertical gas flow in separators. The vanes are assembled in custom-designed frames with pre-determined vane spacing and gas-sealed liquid pockets on both sides of the vanes — preventing re-entrainment of captured liquid by high-velocity vapor.

Gas passes between vanes with strategically arranged openings. Droplets are separated from the gas stream by inertial forces and captured into an enclosed liquid pool, effectively eliminating re-entrainment even at high gas velocities. The MPV Vane Pack may be combined with other AMT separator internals for fully optimized multi-stage separation.

Z-Pack De-Entraining Device

The AMT Z-Pack De-Entraining Device is a vane-type mist eliminator designed specifically for horizontal or vertical gas flow. The vanes are assembled in custom-designed frames with the design vane spacing, gas seals, and drain arrangement for the specified process requirements.

The gas passes between parallel sinusoidal vanes fitted with strategically arranged hooks, separating droplets in two distinct stages. Coarse droplets and suspended solid particles are captured at the first hook, while smaller droplets are captured at the second hook after acceleration through the venturi throat created by the first hook housing. The captured liquid drains down the hooks into the bottom liquid pool. The Z-Pack may be combined with other AMT separator internals for multi-stage separation systems.

Agglomeration Device

The AMT Agglomeration Device is a 4–6 inch (100–150 mm) thick uniform wire mesh pad with a high free volume and large surface area for liquid contact. Unlike conventional mesh pads used for direct mist elimination, the Agglomeration Device is specially designed to operate at higher vapor loadings — conditions that would cause a conventional mesh pad to flood.

At these higher loadings, a clearly defined liquid reservoir develops within the mesh and fine droplets coalesce into larger droplets. These larger droplets are then re-entrained into the gas stream and carried to a downstream high-performance mist eliminator — such as the AMT MPV Vane Pack or Z-Pack — for final and complete removal. This staged approach achieves superior overall separation performance compared to any single-stage device.

The Agglomeration Device is cost-effective and easily installed in new and existing vessels. It is always recommended to be used upstream of and in conjunction with a high-performance separator internal.

AMT Mist Eliminators

AMT Mist Eliminators are porous mesh pads composed of knitted wire or plastic filament in crimped stacks, bound by a frame. They provide a high free volume and a large liquid impingement surface for the removal of fine particle size mists from gas streams. Pads are typically 4–6 inches (100–150 mm) thick and can be designed and installed in two-phase separators, three-phase separators, and distillation columns.

AMT offers a comprehensive range of mist eliminator types — from ultra-high efficiency fog coalescers for the most demanding fine mist applications through to economy high-throughput designs for standard service. Anti-fouling configurations are available for services prone to solid deposition.

Contact AMT's engineering team with your process conditions and we will recommend the optimal mist eliminator type and configuration for your specific service.