Diluted Bitumen Railcar Vapour Control - LBCG · • Lean Oil Absorption ... Safer Vapour Control System Implementation. N ... Vapours from blended / diluted bitumen

Rangeland Engineering Company Ltd.Suite 400, 534 – 17th Avenue SW

Calgary, Alberta Canada T2S 0B1Tel: (403) 265-5130 Fax: (403) 265-5163

W W W . R A N G E L A N D E N G . C O M

Diluted Bitumen RailcarVapour Control:

Safety Concerns in the Transport Industry

Authors: Todd Kennedy*Freddy Arias

* Corresponding author

Rangeland Engineering is based in Calgary, Alberta. We are a midsize full-service engineering, procurement and construction management (includes process, mechanical, electrical, civil,

structural and instrumentation disciplines) company.

Our focus is the midstream market and we specialize in rail and truck terminals, product treatment and storage including salt caverns, oil and gas processing, and natural gas liquids.

We support the entire project lifecycle - from feasibility studies to detail design to commissioning and start-up. We partner with clients to simplify process, reduce costs and waste, improve

constructability, ensure reliability, and optimize design.

Look to some of the biggest and best energy companies in Alberta and you’ll find a team of Rangelanders embedded in the design and development of their projects

http://www.rangelandeng.com/

Introduction to Rangeland

1. Introduction & Background2. Loading Operation3. Vapour Pressure and Composition4. Offloading Operation5. Flammable Mixtures6. Vapour Control7. Recommendation #1 – Process Purge8. Recommendation #2 – Separation 9. Recommendation #3 – O2-free Displacement10.Conclusions

OUTLINE

Source: http://www.aogr.com/web-exclusives/exclusive-story/rail-gives-oil-shippers-new-capacity-flexibility

Source: Transporting Crude Oil by Rail in Canada, Canadian Association of Petroleum Producers, March 2014


OUTLINE

Loading Operation

“Open” Loading System

Loading Operation

“Open” Loading System

Previously Undefined Vapours Released to

SurroundingsDiluted Crude Oil to

Railcar

Loading Operation

“Closed” Loading System

Loading Operation

“Closed” Loading System

Previously Undefined Vapours to Vapour Collection Header

Diluted Crude Oil to Bottom of Railcar (valve connection)


OUTLINE

Vapour Pressure and Composition

Predicting Railcar VapourHydrocarbon Concentration


Impacts on Vapour Pressure


Impacts on Vapour Pressure

Blending Ratio Impacts TVP

$$$

Source: http://www.crudemonitor.ca/condensate.php?acr=CRW


Edmonton Condensate Blend (CRW-705)August 9, 2015


OUTLINE

Offloading Operation

“Open” Offloading System



Air Enters Railcar fromAtmosphere

Diluted Crude toCollection Header

Composition in VapourSpace Remains Constant



TVP of Liquid Determines

Quantity of Air is Drawn into Car

TVP of Liquid Determines Quantity of Vapours Released

from Liquid



OUTLINE

Flammable Mixtures

Reid Vapour Pressure (RVP)— a term commonly defined by ASTM D323 Reid Vapour Pressure Method - used to describe the pressure exerted by an air saturated fluid at a vapour/liquid ratio of 4:1 at 37.8°C.

- Canadian Crude Quality Technical AssociationCCQTA Information Regarding the Measurement and

Reporting of Light Ends and Vapor Pressure of Live Crude oil

Flammable Mixtures

Source: API Recommended Practice 2003: Protection Against Ignitions Arising Out of Static, Lightning, and Stray Currents

Flammable Mixtures

Simple flow diagram for University of Calgaryheavy oil lab experiment

Flammable Mixtures

University of Calgary heavy oil lab experiment

Flammable Mixtures

University of Calgary heavy oil lab experiment

Flammable Mixtures

Model Railcar Vessels on Shaker TableUniversity of Calgary heavy oil lab experiment

Flammable Mixtures

Dilbit results of U of C experimentand actual field sample

Raw Composition (mol%)

Theoretical (Eq.1)

Bench Scale Experiment

(U of C)

Operational Railcar Sample

Methane (C1) 0.00 0.00 0.82

Ethane (C2) 0.17 0.18 0.03

Propane (C3) 0.62 0.46 0.10

iso-Butane (iC4) 0.19 0.11 0.35

normal-Butane (nC4) 3.63 2.00 0.90

iso-Pentane 8.19 3.73 2.94

normal-Pentane 5.62 2.56 2.24

normal-Hexane 0.53 0.20 0.73

Normal-Heptane 1.29 0.01 0.28

Nitrogen 63.10 71.69 73.72

Oxygen 16.77 19.06 17.81

Total Hydrocarbons 20.1 9.3 8.4

LFL Mixture 1.5 1.5 1.5

UFL Mixture 7.9 8.1 8.2

Auto-ignition Temp. 356°C 372°C 367°C

Traveling Mixing Effect

Railcar Vapour GenerationShaking and Temperature Mechanisms

Flammable Mixtures

Effect of travel between different climates

Temperature Drop Could Push Vapour Composition

into Flammable Range

TVP Could Drop With Temperature Drop As

Car Travels North

Higher TVP Could Present a Rich Hydrocarbon Mixture in High

Temperature Climate

Flammable Mixtures

Effect of travel between different climates


OUTLINE

1. Vapour Destruction Units (VDU)• Flares• Incinerators• Catalytic Oxidizers

2. Vapour Recovery Units (VRU)• Vapour Balancing• Carbon Adsorption• Lean Oil Absorption• Condensation/Refrigeration• Membrane Separation

Vapour Control

Image Source: https://en.wikipedia.org/wiki/Fire_triangle

Vapours from blended / diluted bitumen

Vapour Control

“The Fire Triangle”

• Flammable Railcars Perceived as Empty• Explosion Risk During Transportation• Fire Risk at Loading Terminals• Safety Risk to Operating Personnel

• Liability and Reputation Risk!

PROBLEM:


OUTLINE

Recommendation #1Process Purge

Current Vapour Control System Implementation


Safer Vapour Control System Implementation

N2 Purge:• Limits O2 content below

LOC• ~ 4¢ per barrel of oil

loaded

CH4 Purge:• Increases HC

concentration above UFL• ≤0.5¢ per barrel of oil

loaded



OUTLINE

Recommendation #2Separation

Undiluted Crude / Railbit

SAVE $$$

Recommendation #2Separation

Other Safe Area Away from

Flammable Limit


OUTLINE

Recommendation #3Oxygen-Free Displacement

“Closed” Offloading System


“Closed” Offloading System


O2-Free Gas Displacing Liquid

(e.g. N2, CH4)Railcar Remains

O2-Free at All Times

Image Source: https://en.wikipedia.org/wiki/Fire_triangle

Vapours from blended / diluted bitumen

• Eliminates an entire side of the “Fire Triangle”

• Cost depends on gas used and associated price in local market

• Cost should be similar to recommendation #1 ~2 – 4 ¢ per barrel of oil offloaded.


Target Region forRailcar Vapour Space


Target Region


OUTLINE

• Recommendation #1 – Purge Headers at Loading Terminals– Quick to implement– Doesn’t eliminate explosive mixtures within

railcars– Can be implemented by loading terminal

operator without impact to customers– Relatively inexpensive to operate– Less than 5¢ per bbl of liquid shipped

Conclusions

Protect your assets and protect your people!

• Recommendation #2 – Remove Light Ends– Requires higher capital cost investment– Additional cost saving in recovering diluent

• Price of condensate is currently ~$65/bbl• 2020 forecasted price is ~$100/bbl by 2020

– Will require heat to offload– Implemented by loading terminal– Operating cost will be very site dependent

Conclusions


• Recommendation 3# – Eliminate Oxygen– Safest option– Protects full transportation cycle– Implemented at offloading terminal– Would require industry consensus unless

operating with guaranteed dedicated fleet of cars– Relatively inexpensive to operate – Less than 5¢ per bbl of liquid shipped

Conclusions


Conclusions

Your assets, employees, liability, and reputation are worth hundreds of millions of dollars.

You can’t afford not to protect them……especially for a nickel per barrel.

5¢

Liability: $500,000,000Damages: $300,000,000Human Life: Priceless

Estimated cost of a single catastrophic incident

per barrel

QUESTIONS?

Documents

Diluted Bitumen Railcar Vapour Control - LBCG · • Lean Oil Absorption ... Safer Vapour Control System Implementation. N ... Vapours from blended / diluted bitumen