Oilfield NGL Liquid Handling

8/15/2019 Oilfield NGL Liquid Handling

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Prism MidstreamUnderstanding How to Treat Off-Spec NGL’s Doug Coleman – Vice Presiden t

NGL Recovery Optim izat ion & Cryo p lant Faci l i t ies Design 2015

17 February - 18 February 2015 | Houston, Texas


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Founded in 2000 by a management team comprised of former

employees of Union Pacific Resources Corporation

Gathering and Processing platform in East Texas

• 320 MMscfd gas processing plant

• 14,500 Bpd of fractionation

• 700 miles of pipe• Truck NGL and Condensate loading and unloading facilities

• Rail loading and unloading access

Prism Gas Systems was sold to CNP in June 2012

Prism Gas Systems

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Founded in 2012 as Prism Midstream LLC with Energy Spectrum

Company Focus

• Texas natural gas gathering and processing

• Crude gathering and transloading

• Liquids handling

Assets• Transloading facility in Pecos, Texas

• Two stabilization facilities in the Permian Basin

• 153 mile Eaglebine area gas gathering system

Prism Midstream

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Understanding how to treat off spec NGL’s from

Refrigeration and JT Processing Plants

Review of typical NGL and NGL pipeline specifications

Evaluation of the causes of off spec NGLs and the associated

operational problems

Methods for treating NGL’s for color, H2S, CO2, and high methane

or high C1/C2 ratio

Liquids Handling

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Typical NGL specifications

Composition

• Carbon Dioxide

• Methane

• Ethane

• Aromatics• Olefins

• Vapor Pressure

Corrosiveness• Copper Strip @ 100⁰ F

• Total Sulfur• Hydrogen Sulfide

NGL Specifications

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Typical NGL specifications (continued)

Color

• Saybolt number

Dryness

• No free water or

• No free water at a specific temperature

• Hydrogen Sulfide

NGL Specifications

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Typical NGL “Pipeline” specifications

Generally include the previous specifications and tests for

• Olefins

• Distillation end point

• Halides including fluorides

• Maximum pipeline temperature• Generally include the previous specifications and tests for

A field test to check that the NGL product is “water white”

NGL Specifications

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NGL Specifications

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Lone Star NGL Pipeline

• Energy Transfer

• West Texas to Mount Belvieu

• 1170 miles of pipeline

• 137,000 Bbls/day capacity


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NGL Specifications

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Lone Star NGL Pipeline

• CO2, 500 ppm max

• Vapor Pressure, 600 psig

@100deg F

• Copper Strip @ 100 deg F, No.1• Hydrogen Sulfide, Pass on

ASTM D-2420

• Color, +25 Saybolt

• Dryness, No free water

@34degF


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NGL Specifications

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Sandhills NGL Pipeline

• CO2, 1000 ppm max

• Vapor Pressure, 600 psig

@100deg F

• Copper Strip @ 100 deg F, No.1• Hydrogen Sulfide, Pass on

ASTM D-2420

• Total Sulfur, Max 150 ppm

• Color, +27 Saybolt

• Dryness, No free water

@34degF


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Typical causes of off spec NGLs

High CO2• CO2 composition spikes in the inlet gas production

• Running the unit too cold to increase production

High C1/C2 ratio

• Running the unit too cold• Failure to plan, no NGL stabilizer installed along with the

Refrigeration or JT plant

Causes of Off Spec NGLs

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Typical causes of off spec NGLs (continued)

Off Color

• Rust from the internals of a new pipeline or “new-used”

storage

• Crude carry over from field production facilities

• Water contamination and associated “dyes”

High H2S

• Failure of upstream H2S scavenger injection facilities

• Condensate/crude carry over from field production

Causes of Off Spec NGLs

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Treatment for high C1/C2 and high vapor pressure

Running too cold; warm up the unit

• High C1 or C1/C2 ratio

• Most refrigeration and JT units are not designed operate below

-40⁰F

• Too high vapor pressure product to truck

• NGL stabilizer to drive off the CO2 and ethane if not included in

the original design

NGL stabilizer to remove CO2

Treating for High C1 / C1/C2 ratio

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Solutions for high CO2 NGLs

Warm up the unit; running too cold

• High CO2

• Too high vapor pressure to truck

• Install a NGL stabilizer to drive off the CO2 and ethane if not

included in the original design

Install NGL stabilizer to remove CO2 and ethane

Chemical scavenger

• Amine or other chemical that will “bind” the CO2• Settles out at the storage• Expensive to operate

Treating for High CO2

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Solutions for off color NGLs

Charcoal Filter

• Similar to a Charcoal filter for an amine unit

• Removes the heavier hydrocarbons and dyes that cause

NGL’s off spec for color

Condensate stabilizer or “weathering” • If the color is due to a large carry over crude would rapidly

deplete the charcoal bed

• Stabilizer separates the NGLs from the crude equivalent which

contains the color

Treatment for Off Color NGLs

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Treatment for sour NGLs

H2S scavenger

• Amine or other chemical that will “bind” the H2S

• Settles out at the storage and drained with any water

• Expensive to operate

Caustic Treater (KOH)• Typically an “experienced” vessel or vertical filter

• Cost effective but once the caustic is spent it needs to be

replenished

Amine Unit Treater• Well known process and cheaper operating costs than a

caustic treater

• Highest capital costs

Treating for High H2S

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C O N F I D E N T I A L

Prism Liquid Handling Facility

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Project

• Provide liquids handling services for

growing Permian Basin production• On spec and off spec NGLs

• Field condensate

• Improved netbacks, one stop shop

• Proven experience in the area

Scope• Trucking loading and unloading facilities

on US HWY 190 in Crockett County

• NGL injection point

• Caustic treater for treating of NGLs for

H2S and CO2

• NGL stabilizer for treatment of high C1 or

C1/C2 ratio

• 2000 BBL/day condensate stabilizer


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Pecos Transloading Facilities

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Transloading Facility

• Manifest service

• Multiple purchasers

• Current capacity 15,000 Bpd

• Developing unit train capabilities

• Multi Commodity

• Crude Oil• Condensate

• Frac Sand

• Tubulars


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Leon County - Bright Star System

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Bright Star

• 153 mile gas gathering system

• Serves Leon and Houston Counties

• In the heart of the Woodbine / Eagle

bine play

• Developing a crude gathering system

with a section of under utilizedpipeline


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Oilfield NGL Liquid Handling