NGL TREATING TECHNOLOGIES PROVEN TECHNOLOGIES FOR FRACTIONATION PLANT OPTIMIZATION

Pentair Porous Media 4301 West Davis, Conroe, Texas 77304 • Phone (936) 788-1000 • Fax (866) 539-9032 www.porous.com

The enclosed information is the property of Pentair Porous Media and is furnished in confidence solely for the purpose of evaluating Pentair Porous Media technology.

It is not to be copied, communicated or distributed without the expressed written consent of Pentair Porous Media

Pentair’s Porous Media technologies have been optimizing plant performance for

over a quarter century. Today Pentair serves the energy industry with the most

efficient and most reliable solutions to process challenges from the well head to end

user through performance enhancing separations solutions. We’ve focused our

solutions on NGL processing from initial separation and recovery to pipeline

transport, storage and fractionation. Pentair’s ongoing commitment to technology

development has brought our revolutionary POLAREX technology to the acid gas

treating of NGL allowing a dramatic change in the pre-treatment of NGL prior to

fractionation.

NGL fractionation is the key to unlocking the value created by recent advances in

shale gas and liquid rich gas development. Tremendous growth in NGL production

and subsequent fractionation demand has fundamentally changed the requirements

of the NGL processing industry. In response, Pentair has developed a suite of

technologies to simplify the front end treatment of NGL at fractionation facilities

while dramatically increasing the flexibility and operational reliability of the

fractionation plant. This starts with feed purification. Pentair’s PROCESSOR feed

filtration systems are coupled to our LIQUISEP separators providing feed to the plant

which is free of both suspended solids and entrained water or brine. The

PROCESSOR and LIQUISEP technologies provide high efficiency filtration and

separation with the lowest capital and operational costs in the industry.

Additionally, higher purity feed results in minimized corrosion, fouling and scale

deposition which translates to greater system reliability, reduced maintenance,

higher throughput and greater operating profitability.

The heart of the NGL treating system prior to fractionation is amine treating for

residual CO2 removal. Minimizing CO2 in the ethane product is essential to

delivering product within specification and maximizing production. Pentair’s

POLAREX technology has revolutionized the amine treating of NGL liquids. POLAREX

is used in lieu of a conventional contacting column resulting in tremendous gains in

operational performance and installed capital costs one-third that of conventional

contacting towers. The POLAREX technology is also modular, easily transported to

site and requires significantly reduced footprint and civil work relative to

conventional contact towers.

Pentair Porous Media 4301 West Davis, Conroe, Texas 77304 • Phone (936) 788-1000 • Fax (866) 539-9032 www.porous.com

The enclosed information is the property of Pentair Porous Media and is furnished in confidence solely for the purpose of evaluating Pentair Porous Media technology.

It is not to be copied, communicated or distributed without the expressed written consent of Pentair Porous Media

Engineered for Efficiency

Pentair Porous Media’s technologies are widely applied in NGL treating schemes prior to fractionation and are recognized as the

optimal design for NGL fractionation plants. Pentair has provided the front end treatment for nearly one-third of the installed or

planned fractionation capacity located at Mont Belvieu, Texas - North America’s NGL fractionation and trading hub. Y-Grade NGL pre-

treatment and amine treating prior to fractionation employ Pentair Porous Media’s proven, patented POLAREX® systems as the heart of

the treating process and Pentair Porous Media’s separations systems for fluid quality assurance throughout the treating process. A

typical system provided by Pentair is that outlined in the process flow diagram above [with the exception of the molecular sieve

dehydrator (5), the regenerant heater (6) and the regenerant cooler (7)]. In a typical installation Y-grade NGL is initially treated with

Pentair’s PROCESSOR™ feed filtration system coupled with our LIQUISEP® technology in the Feed Coalescer for the removal of

suspended solids and free water / brine. Together the PROCESSOR and LIQUISEP technologies assure that the NGL fluid is free of

particles which may otherwise foul the treating system and assures that essentially all free water or brine will be removed from the

NGL. Effective removal of suspended solids and water / brine in the feed prevents the accumulation of salts in the circulating amine

system which could lead to excessive corrosion, minimizes dilution of the amine by excessive water load and minimizes the

accumulation of NORM scales (Naturally Occurring Radioactive Material) in the process equipment. The NGL then passes through two

stages of POLAREX technology to provide high efficiency amine contacting and separation in the Stage 1 and Stage 2 Amine Contactors.

The POLAREX technology replaces conventional amine contactors at a fraction of the cost and with considerable additional operational

flexibility. The arrangement allows amine to be introduced in either or both stages to maximize amine treating efficiency requirements.

A third stage POLAREX system may be employed as the Water Wash Contactor to maximize recovery of entrained and soluble amine in

the NGL prior to molecular sieve dehydration. A typical implementation also includes provision of Pentair’s PROCESSOR filter vessel as

the Regenerant Filter and LIQUISEP separator for the Regenerant Coalescer providing removal of molecular sieve dust and water

recovery from the cooled regenerant NGL stream during regeneration of the molecular sieve beds.

POLAREX® EXTRACTIVE SEPARATIONS TECHNOLOGY FOR AMINE TREATING

Efficiency. Performance. Reliability.

Pentair Porous Media’s POLAREX® technology provides chemical manufacturers, refiners

and gas processors dramatically improved separation of entrained and dissolved

contaminants relative to that achievable through implementation of conventional water

wash or solvent scrubbing towers. Conventional approaches to washing or scrubbing are

often limited by contact efficiency and subsequent separation efficiency, resulting in

limited performance and large capital investments. The POLAREX platform was developed

utilizing our advanced micro and nano-fiber technology to create a single stage, high-

efficiency, structured contactor / separator.

The patented POLAREX technology may be applied to the extraction of soluble

components from either liquid or gas process streams. The POLAREX technology has

application to both contaminant removal (e.g. - caustic, dissolved acids, salts, acid gases or

reaction by-products) as well as recovery of valuable products or solvents (e.g. – recover

soluble amines from treated LPG or NGL) for as little as 20% of the capital associated with

a conventional contactor or wash system.

Applied to chemical processes, the POLAREX technology increases process speed and

operational flexibility. Traditional approaches to neutralization or product washing

require a lengthy neutralization step followed by decanting and transfer. These steps slow

reactor turn over and frequently result in carry-over of impurities due to the limited

separation effectiveness of decanting, particularly with emulsified product / water

mixtures. The POLAREX technology allows neutralization or washing to proceed on-line

during product transfer, allowing the wash / decant steps to be eliminated entirely.

The POLAREX

technology represents a

compact, modular approach to

the separation of dissolved

contaminants. Historically,

washing or scrubbing made use

of large water wash / coalescers

or large contactor towers to

achieve reasonable performance.

The POLAREX technology allows

high efficiency contact, extraction

and separation at a fraction of

the cost and at a fraction of the

footprint of conventional

approaches; reducing project

capital by up to 80% and

providing a solution that makes

both dollars and sense.

75,000 bbl/day POLAREX®

NGL amine contactor

Reliable, Proven Performance.

Pentair Porous Media’s POLAREX technology may be applied to both gas and liquid process streams. The POLAREX technology has been

installed on liquid process streams from 20 gpm to over 3,500 gpm and with liquid viscosities as great as several thousand centipoise.

The robust design affords reliable performance in a scalable, modular package appropriate for both new capital projects as well as

placement in existing plant environments. Each system is designed to address the specific operational constraints of the facility and

process.

The flexibility of the POLAREX technology has allowed its application as an amine contactor in the amine treating of NGL or LPG for CO2

removal. In this capacity, the POLAREX displaces a conventional amine absorber tower, providing significantly increased operational

performance and flexibility at less than one-third of the installed cost. Additionally, the POLAREX has essentially no entrained solvent

loss to the treated fluid stream. These systems may operate for over two years without the need for addition of make-up amine.

Negligible amine loss also assures that the downstream molecular sieve dehydration system operates reliably. The POLAREX technology

applied as an amine contactor in NGL processing is installed at some of the world’s premier NGL fractionation facilities at operating

rates in excess of 100,000 bbl/day. Illustrated in the image below is a 75,000 bbl/day POLAREX NGL amine contacting system.

The compact footprint also results in significantly lower installed costs. As an example, a POLAREX system employed in a refinery LPG

treating unit made use of a 36” O.D. x 8’ long POLAREX vessel in lieu of a caustic scrubbing tower of 8’ diameter and 40’ height. The

modular nature of the POLAREX allowed the system to be installed within the existing available footprint of the unit, while the

alternative scrubbing tower would have required the additional cost of demolition of out-of-service process equipment to

accommodate the tower.

Please contact us to learn about how Pentair’s POLAREX technology can optimize your process.

POLAREX® EXTRACTIVE SEPARATIONS TECHNOLOGY FOR AMINE TREATING

LIQUISEP® TECHNOLOGY LIQUID-LIQUID SEPARATION OPTIMIZATION

Water Free. Worry Free.

LIQUISEP®

technology was developed to address the inherent deficiencies of conventional

coalescers, making it possible to remove essentially all immiscible liquid dispersions from

liquid process streams. The LIQUISEP technology overcomes the inherent limitations of

conventional separators, vane pack coalescers, wire mesh coalescers and even “high

efficiency” separators allowing superior separations under demanding conditions.

The LIQUISEP technology makes use of proprietary LIQUIFORM™ media and our patented

APEX® element design to intercept entrained droplets of even sub-micron geometries and

effectively remove them from the process. The LIQUIFORM media couples fiber

geometries and surface energies specifically designed to promote accumulation and

removal of the liquid from the process stream. The APEX element design works in concert

with the media technology allowing uniform fluid flow and minimizing the potential for

turbulence and fluid velocities which might otherwise interfere with droplet removal from

the process stream.

In challenging service such as emulsified feed or condensed water (e.g. – steam stripped

distillate products) where conventional coalescers have limited performance, the LIQUISEP

technology excels. Side-by-side comparisons in plant environments have illustrated the

advantage of the LIQUISEP technology relative to conventional “high efficiency”

coalescers. The LIQUISEP technology was run in parallel to a “high efficiency” coalescer to

validate relative performance. At inlet water concentrations of 23,000 ppm – 30,000 ppm,

the measured total water content of the conventional coalescer effluent was 476 ppm –

495 ppm while that of the LIQUISEP technology was 90 ppm – 100 ppm. At the operating

temperature, the water solubility was ~100 ppm indicating that the LIQUISEP technology

was operating at or near 100% efficiency for free water removal. Typical carryover

associated with LIQUISEP technology is 5 ppm – 10 ppm.

Effective recovery

of free, entrained or

emulsified liquids from process

streams mitigates the potential

for process upsets and other

operational challenges

associated with liquid carryover

such as salt deposition,

corrosion, product haze or

solvent loss. Pentair Porous

Media’s engineering expertise

allows optimal design of

separations solutions within a

plant to achieve effective,

reliable operations while

minimizing capital investment

and ongoing operational

expense.

LIQUISEP Inlet (left) and outlet (right)

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POLAREX® The Future of Liquid-Liquid Amine Contacting

Presenter:Carl Hahn Ph.D.

A special thank you to contributing authors and companies:

Jonathan Gonzalez Mark GregoryChris Hjorth

Sharon Maydak Michael McDowell

S & B Engineers and Constructors, Ltd.Enterprise ProductsAiken Engineering

Pentair Porous Media

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ABSTRACTAmine treating of natural gas liquids (NGL) has historically had no alternative other than traditional methods for contacting the product with amine for carbon dioxide (CO2) and hydrogen sulfide (H2S) removal. These traditional techniques involve contactor columns that use random packing, sieve trays or structured packing. Issues associated with conventional methods are high capital cost, amine carryover, ineffective contaminant removal and plugging/ fouling of columns and distributors/ redistributors. Repairs inside contactor columns can be difficult and expensive, particularly when the cost of downtime is considered. To address the challenges associated with conventional amine contactor equipment, Pentair Porous Media along with Enterprise Products Partners L.P. worked together to implement a Polarex® Extractive Separation system in lieu of a contactor tower for amine treating of NGL streams.

Deployment of the Polarex® System in a LPG/NGL treating process allows positive economic savings for the processor:

• A Polarex® System can provide a near-immediate solution• Significant reduction in size and cost versus the traditional sweetening method• A Polarex® System can be easily relocated to another location when necessary• Provides significant operational stability without the issues associated with conventional contacting technology.

This technology has been successfully used in several NGL treating applications, including installations in facilities operated by Enterprise at the Mont Belvieu complex.

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INTRODUCTIONShale gas has played an important role in the Natural Gas Liquids industry. Over the past decade, the combination of horizontal drilling and hydraulic fracturing has allowed access to large volumes of shale gas that were previously uneconomical to produce. The production of natural gas from shale formations has rejuvenated the natural gas industry in the United States. Over the past ten years the shale formations being explored and developed have significantly increased the natural gas production of the U.S. Available reserves have increased from 150 trillion cubic feet to over 250 trillion cubic feet of natural gas.

Many of the shale gas discoveries are rich with hydrocarbon liquids that are lighter in specific gravity than crude oil. These lighter liquids are categorized as Natural Gas Liquids (NGL). These liquids-rich shale plays have been more sought after and have created production booms in certain regions of the U.S. These production increases have created significant growth in the liquids that feed chemical feed stocks and fractionation facilities. This increase in natural gas liquids has recently made it profitable for chemical companies to once again produce chemicals in the U.S due to the decrease in the price of the NGL feedstocks. This has increased the demand from fractionators across the nation to supply these chemical feedstocks with the necessary liquid hydrocarbons.

NGL products (ethane, propane, normal butane, isobutane and natural gasoline) are used as raw materials by the petrochemical industry, as feedstocks by refiners in the production of motor gasoline and as fuel by industrial and residential users.

• Ethane is primarily used in the petrochemical industry as a feedstock for ethylene production, one of the basic building blocks for a wide range of plastics and other chemical products. • Propane is used both as a petrochemical feedstock in the production of ethylene and propylene and as a heating, engine and industrial fuel. • Normal butane is used as a petrochemical feedstock in the production of ethylene and butadiene (a key ingredient of synthetic rubber), as a blendstock for motor gasoline and to derive isobutane through isomerization. • Isobutane is fractionated from mixed butane (a mix stream of normal butane and isobutane) or produced from normal butane through the process of isomerization, and is used in refinery alkylation to enhance the octane content of motor gasoline, in the production of isooctane and other octane additives and in the production of propylene oxide. • Natural gasoline, a mixture of pentanes and heavier hydrocarbons, is primarily used as a blendstock for motor gasoline or as a petrochemical feedstock.

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NGL FRACTIONATIONNGL fractionation facilities are designed to separate the NGL feed stream into its individual product components. Most fractionation plants consist of three (3) steps. Please refer to Figure 1. below, for a general overview of the process.

1. Raw NGL Treating that consists of feed filtration, water separation and CO2 removal.2. Dehydration processes remove the soluble water in the NGL stream3. Fractionation separates the NGL feed stream into the commercially desirable products of ethane, propane, normal butane, isobutane, and natural gasoline. This process is carried out through a series of distillation towers.

NGL Treating

Dehydration

Deethanizer

Depropanizer Debutanizer

Ethane to pipeline

Natural Gasoline to Storage

i-Butane to Pipeline/ Storage

Propane to Pipeline/ Storage

Y Grade NGL From Pipeline/

Storage

N- Burane to Pipeline/ Storage

Figure 1. PFD of NGL Fractionation

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CONVENTIONAL NGL TREATING EQUIPMENTTraditionally, operators have utilized conventional sock filters, string wounds, mesh pads or vane pack type housings for the removal of particulates and/or water on the front end of fractionation plants. For CO2 removal from the NGL, conventional contactor columns have traditionally been used. These types of conventional treating equipment have been utilized over the past 50 plus years with a varying degree of success and sometimes with considerable costs and operational difficulties. The common issues associated with these conventional devices are:

• High capital costs• Amine losses & make up• Ineffective contamination removal• Plugging and fouling of columns• Costly repairs and loss of production due to downtime

Figure 2 Conventional Contacting Process Flow Diagram

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Conventional liquid-liquid pressure vessels are occasionally installed downstream of the amine columns in an attempt to capture the amine carryover. These conventional devices typically include one or more of the following and have proven to be ineffective at recapturing a significant amount of amine losses:

• Residence time vessels• Hay bale vessels• Mesh pad / vane packs• Coalescing-type vessels with elements.

POLAREX® EXTRACTIVE SEPARATION SYSTEM As an alternative to conventional treating methods and amine contactor towers, Enterprise Products chose to implement Polarex® Extractive Separation Systems at their premier NGL fractionation facilities in Mont Belvieu and Gaines County, Texas. Polarex® technology provides Enterprise Products dramatically improved separation of entrained and dissolved contaminants relative to that achievable through implementation of conventional water wash or solvent scrubbing towers. The Polarex® technology has application to both contaminant removal (e.g. – caustic, dissolved acids, salts, acid gases or reaction by-products) as well as recovery of valuable products or solvents (e.g. – recover soluble amines from treated LPG).

Figure 3 Polarex Process Flow Diagram

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Figure 3 shows a simplified flow diagram of the Polarex® systems installed in the aforementioned Enterprise Products facilities. The lean amine is injected into the NGL stream using the Polarex® Solvent Injection System upstream of the Polarex® contactor. The droplet size of the emulsified amine exiting the injection system is fifty (50) micron and smaller. This droplet size distribution creates an intimate contact between the amine and the Sour NGL for the removal of CO2. This intimate contact allows the mass transfer to occur on the micro-structured extraction media. This level of contact is then immediately followed by the effective means of capturing the dispersed phase and effectively separating it out of the NGL stream. The high specific contact area in a Polarex® system may be an order of magnitude larger than that possible in conventional extraction systems.

Enterprise Products has experienced the following process benefits of Polarex® technology compared to conventional solvent contacting towers:

• Outstanding performance in the removal of contaminants such as caustic, dissolved acids, salts, acid gases or reaction by-products.• Significant reduction in size (Vessel diameter and Footprint)• Significant reduction in capital and operational costs• Shorter lead times for a near-immediate solution (due to the reduced size)• Relative ease to relocate to another location if necessary• Stability of operations without the common issues associated with towers

CONCLUSIONPolarex® Extractive Separation System provides an alternative to traditional methods for contacting NGL product with amine for carbon dioxide (CO2) and hydrogen sulfide (H2S) removal. Enterprise Products initially installed Polarex® Technology at their Hobbs Fractionation Facility, located in Gaines County, Texas, in 2008. Enterprise Products found that this technology provided optimum performance, at a lower cost, a smaller footprint, and a system that was easier to operate. As a result Enterprise Products has since installed several Polarex® systems at its Mont Belvieu, Texas NGL Fractionation facility.