As the hydrogen economy advances across the Transmission sector, and more recently into Utilities and Gas Distribution, we sat down with our subject matter expert, Mario Yturriago, Senior Integrity Engineer at Dynamic Risk, to learn how Hydrogen will continue to play a more dominate role across the pipeline industry in support of environmental stewardship and sustainability.

 

What is hydrogen (H)?

Hydrogen (H) is the lightest and most abundant element in the universe contributing to 75% of the universe’s mass. It is a catalyst for life, providing fuel to our sun, energy to our planet, and bonding with elements essential for life, such as oxygen, to create water. The Periodic Table of Elements represents hydrogen with a “H” as it is one atom of hydrogen and has an atomic number of 1, referred to as “atomic hydrogen” or diffusible hydrogen”.

Granted, with all its abundance, one would expect hydrogen to be easily obtainable within our environment. However, it is this lightness, near weightlessness, that allows hydrogen to easily escape our atmosphere. In everyday life, isolated hydrogen atoms are extremely rare and tend to combine with other atoms in compounds, or with another hydrogen atom to form ordinary (diatomic) hydrogen gas, H₂.

Hydrogen (H₂) is a gas which forms when two hydrogen atoms bond together and become a hydrogen molecule. Often referred to as “molecular hydrogen”. An example is water, where the chemical formula is H₂O, which means a molecule of hydrogen bonds with an oxygen atom into a compound. Hydrogen (H₂) is colorless, odorless, tasteless, and highly combustible.

Molecular hydrogen (H₂) is the gas used in industry and carried through pipelines. Although, not in quantities large enough for industry use. Hydrogen (H₂) is not a source of energy but a carrier of energy so it must be produced.

 

How is hydrogen (H₂) produced?

Hydrogen (H₂) production is currently categorized primarily by the energy source (non-renewable or renewable) used. Secondarily, descriptive coloring (blue or green) representative of the energy source. Tertiary, by the method (e.g., SMR, ATR, or Electrolysis) employed in its production.

Blue hydrogen is hydrogen (H₂) produced from non-renewable energy sources by one of two primary methods. Steam Methane Reforming (SMR) is the most common and uses natural gas (methane) to split into hydrogen (H₂) and Carbon Monoxide (CO). Autothermal Reforming (ATR) uses Carbon Dioxide (CO₂), Oxygen (O) or steam to react to form hydrogen (H₂). It is considered blue whenever the emission generated from the reforming processes are captured and stored underground.

Green hydrogen is hydrogen (H₂) produced by electrolysis of water, using an electric current to break water (H₂O) into its component elements of hydrogen (H₂) and oxygen (O). It is considered green when the electric current is generated by renewable energy sources such as solar power or wind turbine.

 

What are the benefits of using hydrogen to reduce our environmental footprint and reduce emissions?

Hydrogen has significant importance in the pursuit of achieving a state of net zero emissions (carbon neutrality). The immediate benefits of hydrogen will aid in reducing the amount of carbon emissions into the atmosphere which contribute to increased climate change. However, the potential long-term benefits are even greater as hydrogen may become instrumental in providing a sustainable energy solution. Produced by means of renewable energy in virtually unlimited quantities to serve as a fuel source where the combustion of this fuel results in water vapor, net zero emissions.

Examples in terms of blue hydrogen and green hydrogen are:

• Blue Hydrogen – The production of hydrogen through the reforming processes (SMR or ATR) removes hydrocarbons from natural gas. The blending of the produced hydrogen with natural gas reduces the amount of natural gas for consumption thus reducing carbon emissions from entering the atmosphere. The resulting by-product or exhaust resulting from the combustion of the hydrogen is water vapor.

 

• Green Hydrogen – The production of hydrogen through the electrolysis of water generated by renewable energy sources does not emit any negative emissions into the atmosphere.

 

How is hydrogen used within the pipeline industry?

The petroleum refining, metal treatment, fertilizer production and food processing industries require high volumes of hydrogen for their processes and are best serviced through pipeline service. Furthermore, there are emerging industries which also use hydrogen that include energy generation, hydrogen distribution, and fuel cells.

The energy generation sector is actively seeking to transition from the present fossil fuels such as petroleum, coal, and natural gas for thermal power generation to hydrogen. Traditionally, fossil fuels are used to heat water for steam which is used for turbine generators to generate electricity. Hydrogen will replace these fossil fuels, thus preventing the release of carbon dioxide from being a contributing factor in global warning.

Hydrogen distribution is the blending of hydrogen with natural gas or 100% hydrogen service through new pipelines or the retrofitting of current natural gas pipelines to hydrogen for businesses and residential homes. The use of hydrogen equivalent to that of natural gas for common essentials such as heating, hot water heaters, and stove tops. Also, the blending of hydrogen with nature gas is used to reduce the release of carbon dioxide emissions into the atmosphere.

 

What opportunities do pipeline operators have with Hydrogen?

The emergence of a hydrogen economy will provide for growth and new opportunities for pipeline operators. These opportunities include the retrofitting of existing natural gas systems to blended hydrogen/natural gas or 100% hydrogen transmission and distribution pipelines. However, the hydrogen distribution industry is poised to experience the greatest opportunities as new pipelines are installed in service of this expanded service capacity. The advancement of infrastructure to support the hydrogen economy such as production methods, storage, and distribution.

 

What Challenges do operators currently face transporting hydrogen and how does Dynamic Risk support?

The current challenges to pipeline operators transporting hydrogen are comparable to other gases which are classified as flammable, toxic, or corrosive and in transmission service. Examples of gases which are transported through pipelines include natural gas (NG), carbon monoxide (CO), and synthesis gas (SG) and have done so for many years.

An important distinction between molecule hydrogen (H₂) and atomic hydrogen (H) is that molecular hydrogen (H₂) is what is transported through pipelines as opposed to atomic hydrogen (H) which is not purposefully produced but an occurrence under specific conditions. Atomic hydrogen (H) can be produced either internally or externally of a pipeline through chemical reaction which can cause corrosion to pipelines. Sources of atomic hydrogen commonly observed within pipeline operations include:

• Pipe products containing hydrogen sulfide (e.g., sour services)
• Environment exposure (e.g., soil, chemicals, or water)
• Hydrogen ions produced during excessive cathodic protection (CP) reduction reactions.

Hydrogen embrittlement (i.e., hydrogen induced cracking or hydrogen damage) is caused by the diffusion of atomic hydrogen which is generated through a corrosion process at the surface of the steel and extends through the pipe wall. The introduction of hydrogen can reduce the ductility of the pipe wall, causing embrittlement. Since the threat only exists when atomic hydrogen is present, the threat can be categorized as hydrogen cracking.

The mechanisms of hydrogen embrittlement include:

• Hydrogen Enhanced De-cohesion (HEDE)
• Hydrogen Enhanced Localized Plasticity (HELP)
• Absorption Induced Dislocation Emission (AIDE)

Contributing factors leading to the propagation of hydrogen induced cracking include:

• Susceptible pipe material (e.g., API 5L steels),
• A source of atomic hydrogen (e.g., cathodic poisons that inhibit hydrogen recombination at the surface or excess hydrogen formation at the surface),
• Internal or externally applied stresses (e.g., circumferential, or longitudinal loading)

Furthermore, the blending of some gases such as hydrogen with natural gas or 100% hydrogen for distribution service is not common across the industry. Specifically, these products in commercial and residential use. This presents potentials that may require regulatory considerations for safety related to production, distribution, commercial, and residential use.

Dynamic Risk’s prior knowledge and experience within the Transmission and Midstream sector also expands into Facility and Distribution integrity management, providing our clients with industry leading technology enabled consulting services in this emerging market. Our Subject Matter Experts (SMEs) have the knowledge and experience with risk identification, assessment of threats, and consequence evaluation in aiding operators towards continuous improvement.

Our team partners with our clients to provide effective integrity management solutions towards the elimination of pipeline failures with risk- informed decision-making and determining appropriate actions for mitigation.

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About the Author:

Mario Yturriago, Senior Integrity Engineer

Mario has 30+ years’ experience within key industry domains including engineering, IT, and database application and development/support. Mario is currently a Senior Integrity Engineer at Dynamic Risk. Since 2008, his primary focus has been within Pipeline Integrity and Operations, which includes the development and execution of Integrity Management Programs (IMP), integrity assessments, regulatory audits, review and development of standards and procedures and development of risk assessment. Mario holds a Bachelor of Science (B.S.) Industrial Technology from Southern Illinois University.