This page contains Abstracts of research on Crude oil done by the Transportation of Dangerous Goods Directorate.
On this page
- Abstract – Crude oil sampling and analysis: Impact of crude oil properties on flammability properties – March 31, 2021
- Abstract – Rail tank cars exposed to fire: Analysis of thermal conditions in a railcar engulfed in a crude oil fire (Series 1-3 Tests) - March 24, 2021
- Abstract – Crude Oil Equation of State Final Report – October 18, 2019
- Abstract – Task 3: Combustion Experiments and Modeling – August 26, 2019
- Abstract – Heavy Crude: Closed vs. Open Sampling and the Effect on Light End (C1- C6) Composition over Time- March 2019
- Abstract: Crude Oil Sampling and Testing Methods Literature Review - February 8, 2017
- Abstract – Task 2: Sampling and Analysis Method Evaluation February 8, 2017
- Abstract: Crude Oil Sampling and Analysis Final Report - August 10, 2015
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Abstract – Crude oil sampling and analysis: Impact of crude oil properties on flammability properties – March 31, 2021
Crude oil is a flammable, naturally-derived liquid. Its properties vary based on where and when it was extracted. It can also contain measurable amounts of hydrogen sulfide gas, which is toxic. The Transportation of Dangerous Goods Act and Regulations regulate the shipping of crude oil in Canada.
Crude oil shipping by rail has increased in recent years. These shipments often use long trains of crude oil tank cars, and some have derailed. These derailments can involve fires, which means that the intact rail cars filled with crude oil can experience high temperatures for a long time. This can lead to a release of flammable vapours, crude oil pool fires, and boiling liquid expanding vapour explosions.
Transport Canada’s Transportation of Dangerous Goods Directorate commissioned this crude oil sampling and analysis. The project had four (4) key goals:
- To add samples to the directorate’s database of measured crude oil properties
- To learn more about how the flammability of crude oil relates to other properties
- To predict flammability based on other physical and chemical properties
- To understand how crude oil type or packing group line up with measured properties
We collected 25 samples of crude oil from across Western Canada. A statistician made sure that these samples represented the kinds of crude oils that are transported by land in Canada. We tested the samples to measure properties like:
- vapour pressure
- initial boiling point
- liquid composition
- vapour composition
A statistician analysed the results of the tests, along with the results from older crude oil sampling and analysis projects from the directorate, using several statistical analysis tools. This work was done with InnoTech Alberta. This report does not make any direct connections between crude oil properties and fire behaviour.
- There are statistical relations between the flammability properties of crude oil and other crude oil properties
- Crude oils with higher density and/or higher viscosity were more likely to have a lower heat of combustion and a higher initial boiling point
- Models were developed to predict flammability properties from the other crude oil properties
- Gross heat of combustion was much more predictable than initial boiling point
- Vapour phase hydrogen sulfide (H2S ) concentration was only weakly predictable
- Density of crude oil is a key property in the analysis, meaning that crude oils with similar density are more likely to be similar in other ways
Read the summary report: Research summary - Impact of crude oil properties on flammability properties
To get a copy of the report, please contact us.
TP: TP 15460E
Abstract – Rail tank cars exposed to fire: Analysis of thermal conditions in a railcar engulfed in a crude oil fire (Series 1-3 Tests) - March 24, 2021
If rail tank cars that transport crude oil get into an accident, a fire sometimes follows. In order to understand how tank cars will behave in a fire, we need to understand how different crude oils burn and how quickly the oil in a tank car heats up.
In 2015, Transport Canada (TC) partnered with the National Research Council of Canada (NRC) to look at crude oil pool fires. Then, in 2016, due to test facility requirements, TC and the NRC chose Sandia National Laboratories as the place to perform testing in Albuquerque, New Mexico, USA. For the testing, we set fire to pools that were two (2) metres in diameter. We looked at how fire heated an object, and how variations (like type of oil, temperature, quantity of fuel or height of the object) affected the results.
In this study, Sandia National Laboratories analyzed and burned three (3) different fuels:
- Bakken crude oil
- diluted bitumen (dilbit)
We chose these fuels because both Bakken and dilbit are transported in Canada, and because they are some of the most and least dense crude oils that move through Canada. Heptane is a pure substance and was used in the first round of testing as a “control” to help us compare results as it is widely available and well-studied.
In order to measure how a fire can heat an object, we built a special tool called a calorimeter. This tool is a cylinder and has temperature measuring devices (thermocouples) at different points on the outside and inside which allows us to measure the differences in temperature between these two areas.
The calorimeter was built to represent a tank car and was 1/10th the size of a rail tank car. We also used other tools to measure flame properties to find out how much heat the fire released.
For each crude oil fuel, we looked at different test arrangements and changed these aspects from test to test:
- how high above the fuel we placed the calorimeter
- whether the calorimeter was used or not
- whether or not there was a steady flow of fuel into the fuel pan
- differences in fuel supply temperature (20°C or 60°C)
The study showed that Bakken crude oil and heptane burned steadily in a way that was easy to measure and analyze. The dilbit burned unsteadily, which we found was due to its high levels of heavy hydrocarbons compared to the other two test fuels.
The calorimeter absorbed more heat from both the Bakken and dilbit oils, even though the heptane fire burned hotter. The soot produced from burning a “dirtier” oil led to the calorimeter absorbing more heat.
We found that changing the different aspects listed above had little effect on the test results. Both heptane and Bakken burned 10% faster when the fuel was warmed. The dilbit tests were difficult to compare to the other fuels because the fire burned unsteadily.
All of this information is available in the full report from the NRC. It also includes Sandia National Laboratories’ reports on the fire testing and their analysis of the crude oil’s composition.
To get a copy of the report, please contact us.
TP: TP 15465
Abstract – Crude Oil Equation of State Final Report – October 18, 2019
More and more crude oil is being shipped by rail, and there is growing interest in understanding the risks of this kind of transport.
During a rail accident, tank cars carrying crude oil may be exposed to extreme fire temperatures for long periods of time. Because crude oil can have widely different compositions, it is hard to predict how it may behave when this happens. Another complication is that tank cars have pressure relief devices, which may allow some crude oil to escape (vent) from the tank car. Venting can change the crude oil still inside the tank car.
The Transportation of Dangerous Goods Directorate commissioned this study, which had two key objectives:
- To better understand how crude oil behaves in closed containers (such as tank cars) exposed to fire conditions up to 950°C. Specifically, to understand how this changes due to boiling, venting and chemical reactions.
- To develop a computer model that can predict crude oil properties at high temperatures, and compare its predictions to lab test results.
This work was done with CanmetENERGY, Natural Resources Canada.
- We developed a computer model that can predict properties of various crude oils at high temperatures. This initial model was able to account for venting but not chemical reactions.
- Building on the initial model, we added some chemical reactions to create a “reacting model.” This model could predict thermodynamic properties and crude oil composition in liquid and vapour phases, at high temperatures and pressures.
- We tested three crude oils in a lab at high temperatures and pressures. How those crude oils behaved was very similar to what the computer model predicted.
- Case studies with the reacting model showed that how crude oil behaves in closed containers is different when chemical reactions are added. Because of this, the amount of crude oil pressure relief valves can vent goes down depending on the type of crude oil.
To get a copy of the report, please contact us.
Abstract – Task 3: Combustion Experiments and Modeling – August 26, 2019
The United States (U.S.) Department of Energy (DOE) launched the Crude Oil Characterization Research Study in 2015, with the US Department of Transportation (DOT) and with the Sandia National Laboratories (SNL) serving as technical lead.
Transport Canada is working with U.S. DOE and DOT on this research. Together, they will evaluate whether crude oils transported in North America, including those produced from "tight" formations, exhibit physical or chemical and combustion properties that are distinct from conventional crudes during transportation and handling.
The SAND2019-9189 report, released in August 2019, presents results from Task 3: Combustion Experiments and Modeling, which is part of SNL's comprehensive Crude Oil Characteristics Research Sampling, Analysis and Experiment (SAE) Plan (PDF, 286 KB). The report can be accessed at: https://www.osti.gov/biblio/1557808.
The report describes an experimental study of physical, chemical, and combustion characteristics of selected North American crude oils, and how these associate with thermal hazard distances resulting from pool fires and fireballs.
The emergence of large volumes of tight oils within the North American Transportation system over the last decade coupled with several high-profile train accidents involving crude oils, has raised questions about the role of oil properties in general, and tight oils in particular, in affecting the severity of hazard outcomes in related crude oil fires.
The objective of the pool fire experiments was to measure parameters necessary for hazard evaluation, namely, burn rate, surface emissive power, flame height, and heat flux to an engulfed object. To carry out this objective, a series of 2-m diameter indoor and 5-m diameter outdoor experiments were performed.
The objective of the fireball experiments was to measure parameters required for hazard evaluation which include fireball maximum diameter, height at maximum diameter, duration, and surface emissive power using 400-gallons of crude oil per test.
The crude oil samples used for the experiments were obtained from several U.S. locations, including tight oils from the Bakken region of North Dakota and Permian region of Texas, and a conventionally produced oil from the U.S. Strategic Petroleum Reserve stockpile. These samples spanned a measurable range of vapor pressure and light ends content representative of domestic conventional and tight crudes.
The results indicate that all the oils tested in the study have comparable thermal hazard distances and the measured properties are consistent with other alkane-based hydrocarbon liquids.
If you have any questions or comments about this study, please contact us.
Abstract – Heavy Crude: Closed vs. Open Sampling and the Effect on Light End (C1- C6) Composition over Time – March 2019
Transport Canada (TC) studied heavy crude oil to learn whether one method of sample collection was better than the other in capturing crude oil samples for the purpose of compositional analysis.
Several methods exist to collect crude oil samples in the field. In two previous sampling and analysis campaigns, TC used a closed floating piston cylinder to collect crude oil, but the method was challenging for some heavy crude oils due to their high viscosity.
In our latest study, we wanted to learn if collecting heavy crude oils using open sampling under atmospheric pressure would cause significant loss of light ends from the oils (i.e. hydrocarbon gases such as methane (C1) and propane (C3)) as compared to the closed floating piston cylinder method.
We presumed that heavy crude oils contain trace amounts of light ends. As well, because heavy crude is so viscous, it could be harder for light ends to diffuse out of the crude oil. So we also presumed there would be a negligible loss of light ends, regardless of the type of sampling method used.
In the study, we collected four crude oils – three heavy and one light – using both open and closed methods. We analyzed the samples for light end hydrocarbons (C1 – C6) and retention of light ends over a 4-week period. The comparison of results from Week 0 to Week 4 supported the hypothesis that, in heavy crude oil samples, light ends are present in low to trace amounts and diffusion of light ends out of heavy crude oil at atmospheric pressure is minimal.
We concluded that, when handled and stored properly, collecting heavy crude samples using an acceptable open sampling method does not lead to a significant loss of light end hydrocarbons compared to a closed method.
To obtain a copy of the report, please contact us.
Catalogue Number: T86-55/2018E-PDF
ISBN : 978-0-660-29113-0
Abstract: Crude Oil Sampling and Testing Methods Literature Review - February 8, 2017
The Transportation of Dangerous Goods Program commissioned a literature review comparing sampling and analysis methods and their appropriateness to a number of Canadian crude oils. Currently there are significant variations in the type of sampling and analysis techniques used for crude oil classification prior to the oil being transported in Canada. A specific sampling method may only be suitable for certain types of crude oils and certain analytical methods. By the same token, for a specific analytical test, one sampling method may work better than another, depending on the type of crude oil. As a result, InnoTech Alberta, a provincial research corporation, undertook this work. The literature survey concluded that sampling into open containers under atmospheric pressure is suitable for collecting samples of dead crude oils, heavy crude oils, and for test methods where the loss of light components will not affect the accuracy of analytical techniques. Sampling under closed conditions should be done whenever there are any concerns about the loss of volatiles and for light oils including condensates, and diluted bitumen. In terms of test methods, those that allow direct sample introduction from a pressurized cylinder into the instrument (such ASTM D8003) and eliminate evaporative losses prior to analysis are preferred. Density and hydrogen sulfide content measurements can also be affected by the loss of volatiles and therefore methods that call for closed sampling are recommended.
To obtain a copy of the report, please contact us.
Abstract - Task 2: Sampling and Analysis Method Evaluation - February 8, 2017
The United States (US) Department of Energy (DOE) launched the Crude Oil Characterization Research Study in 2015, with the US Department of Transportation (DOT) and with the Sandia National Laboratories (SNL) serving as technical lead.
Transport Canada is working with US DOE and DOT on this research. Together, they will evaluate whether crude oils transported in North America, including those produced from "tight" formations, exhibit physical or chemical and combustion properties that are distinct from conventional crudes during transportation and handling.
SNL's comprehensive Crude Oil Characteristics Research Sampling, Analysis and Experiment (SAE) Plan (PDF, 286 KB) makes recommendations it describes as distinct tasks. These tasks describe the research needed to improve understanding of tight crude oil properties, especially as they compare to conventional crude oil properties and relate to transportation.
Task 1, a literature review entitled 'Review and Evaluate New and Emerging Crude Oil Characterization Data' is complete; TC did not participate on this task. You can find a report at http://prod.sandia.gov/techlib/access-control.cgi/2015/151823.pdf (PDF, 7.3 MB).
The SAND2017-12482 report (released in December 2017) presents results from Task 2: Sampling and Analysis Method Evaluation.
The aim of Task 2 was to identify commercially available methods that accurately and reproducibly collect and analyze crude oils for vapor pressure and composition, including dissolved gases. The project team selected several sampling and analysis methods, then compared their performance to that of a well-established mobile laboratory system; the current baseline instrument system for the U.S. Strategic Petroleum Reserve Crude Oil Vapor Pressure Program.
Specifically, using crude oil sampled from two specific locations in the US, the experimental matrix evaluated performance for both:
- capturing, transporting, and delivering hydrocarbon fluid samples from the field to the analysis laboratory
- analyzing for properties related to composition and volatility of the oil, including true vapor pressure, gas-oil ratio, and dissolved gases and light hydrocarbons
The report SAND2017-12482 was revised (June 2018) and a new report (SAND2018-5909) "Revision 1 – Winter Sampling" was issued. This report incorporates additional seasonal data and compositional analysis results that have become available since the publication of the prior report, SAND2017-12482, in December 2017.
Going forward, the project team will use methods that performed well in Task 2 in:
- Task 3 (Combustion Experiments and Modeling)
- Task 4 (Compositional Analyses of Multiple Crude Types)
You can access the original Task 2 report (SAND 2017-12482 report released in December 2017) at https://www.osti.gov/scitech/biblio/1414422-doe-dot-crude-oil-characterization-research-study-task-test-report-evaluating-crude-oil-sampling-analysis-methods.
You can access the Revision 1 of the Task 2 report (SAND2018-5909, June 2018) at (https://www.osti.gov/biblio/1458999-doe-dot-crude-oil-characterization-research-study-task-test-report-evaluating-crude-oil-sampling-analysis-methods).
If you have any questions or comments about this work, please contact us.
Abstract: Crude Oil Sampling and Analysis Final Report - August 10, 2015
The July 6, 2013 Lac-Mégantic derailment and other incidents in Canada and the United States have raised many questions about the safe transport of crude oil by rail. They also put a spotlight on the need to further investigate crude oil properties and behaviour.
This report describes the testing the Transportation of Dangerous Goods Directorate has done to assess the composition and properties of crude oils transported by road and rail in Canada. We:
- Verified the applicability of the current classification requirements described in the Transportation of Dangerous Goods Regulations (TDGR) Part 2, for Class 3, Flammable liquids; and Class 2, Gases.
- Focussed on assessing other hazards that crude oil may pose during transport.
68 samples of crude oil were collected and analysed. The crude oil was destined for transport by rail or road in Canada and represents a wide range of crude oils from condensates to bitumen, under controlled conditions. We also subjected the samples to a variety of tests including but not limited to:
- Flash point determination
- Initial Boiling Point determination (IBP)
- Reid Vapor Pressure (RVP)
- True Vapor Pressure (TVP)
- Compositional analysis and Gas Oil Ratio by gas chromatography (GC)
- Hydrogen sulphide (H2S) analysis in the vapor phase and flammable gas testing
- The GC method found IBPs that put 56 out of the 68 samples in Packing Group I, the highest hazard group for Class 3 Flammable Liquids.
- The ASTM D86 method, a commonly used standard for IBP testing of flammable liquids, found IBPs consistently higher than the GC tests.
- The Report recommends using the method that combines GC data from two ASTM standards (D8003/ D7169) as a more accurate method for determining IBP of crude oil containing light ends (methane, ethane, propane and butane).
- Most TVP values were above atmospheric pressure (101 kPa) at 50 oC.
- TVP values were higher than the RVP values for the crude oil samples tested by both methods.
- Based on compositional analysis, one crude oil sample contained enough amounts of light ends to result in a TVP above 300 kPa at 50 oC, which meets the TDGR's definition of a gas.
- Vapour phase measurements of H2S ranged from 0-65000 ppm, with 42 of the 68 crude oil samples having values below 1000 ppm.
We performed this testing with Alberta Innovates-Technology Futures (AITF), an Alberta provincial research corporation.
To support the published report, the crude oil data collected during this project is now available upon demand.
The data set is presented in Microsoft Excel and contains the following information on the samples:
- Region of origin;
- Sample type (e.g., heavy oil, condensate, etc.);
- Sampling method (atmospheric or pressurized);
- Inbound and outbound mode of transportation (rail, pipeline, truck);
- Hydrogen sulphide (H2S) concentration in the vapor phase (ppm);
- Flash point (°C);
- Water and sediment content (%);
- Density (kg/m3);
- Initial Boiling Point (IBP) (°C);
- Reid Vapor Pressure (RVP) (kPa);
- True Vapor Pressure (TVP) (kPa);
- Gas Oil Ratio (m3/m3);
- Simulated distillation profile; and
- Compositional analysis (%).
Note: The data set does not name the companies that own or operate the facilities at which we took samples or the exact geographic point of sampling.
To obtain a copy of the report or of the dataset, please contact us.