Hydrogen (H2) only produces water when burned. This feature makes H2 an essential energy source for a low-carbon future, but current hydrogen production methods continue to produce greenhouse gases.
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Over 90 % of hydrogen production results in ‘grey’ hydrogen produced via steam methane reforming (SMR) or ‘blue’ hydrogen produced via carbon capture utilization and storage (CCUS). Only a small percentage of the produced hydrogen is "green", generated renewably via electrolysis.
The integration of hydrogen also faces a range of challenges, including storage limitations, flammability risks, and high production costs. There is also a need for significant investment to further develop hydrogen production and distribution.
Servomex is a leader in gas analysis, offering advanced solutions including for air separation unit (ASU) applications. The company’s support helps ensure regulatory compliance, safety, and operational efficiency, making ASU viable for all industrial applications.
The Role of Hydrogen Production
A total of 97 million tons (Mt) of hydrogen (H2) is used each year globally, with refineries converting half of this supply into petrol, diesel, and other products.
Hydrogen gas could now replace the fossil fuels used to produce it. However, production demand for H2 is projected to increase sixfold in the next 25 years. This would see demand for hydrogen reaching 125-585 Mt per year (Mtpa).
This huge shift comes with a range of technical challenges, despite representing a significant business opportunity.
A multifaceted strategy is required to reach net-zero by 2050, with a combination of electrification, renewable power, and energy efficiency potentially mitigating 70 % of emissions.
Decarbonizing heavy industry required a different approach. Essential materials produced by this sector are relied upon worldwide, including cement, steel, and aluminum.
It is not possible to simply use less of these materials, as demand is expected to rise by up to 80 % by 2050. This demand is partly in response to the need to develop renewable energy infrastructure.
Production of these materials typically requires temperatures above 1000 °C, which can be challenging to power solely from renewable sources. It is important to note, however, that carbon dioxide (CO2) is a natural byproduct of a wide range of chemical processes, including the manufacture of cement, plastics, and steel.
Hydrogen is a highly reactive element and an established energy carrier, making it a solution to many of these challenges. For instance, industry can burn H2 to generate intense heat while only producing water vapor as a byproduct.
It is also possible to leverage hydrogen to replace fossil fuels in reduction and reaction processes. For example, coal can be switched out for H2 in iron ore processing, reducing emissions from steelmaking by 80 %.
Industrial processes and infrastructure that currently use natural gas can also be adapted to use H2, allowing companies to use existing equipment with only minor modifications and limiting the need to install entirely new systems. One UK report indicated that hydrogen could potentially replace 40 % of fossil fuels employed in manufacturing by 2040.
The Need for Accurate Gas Analysis
Hydrogen is not a magic bullet because its production is currently very carbon-intensive. This means that increased use of the gas could risk offsetting the benefits of switching to it.
It is also important to note that the qualities that make H2 an ideal fuel for heavy industry also make this gas highly dangerous. For instance, hydrogen’s flashpoint is at -43 °C, much lower than that of petrol, meaning that additional safety precautions must be taken.
Hydrogen is also the lightest element with low volumetric energy density, creating additional challenges around its transport and storage unless it is liquefied or compressed. These challenges can be overcome, however.
Utilizing a combination of air separation units (ASUs) and precise gas analysis is key to ensuring safe, efficient, and sustainable hydrogen production. These technologies will prove critical to making H2 a viable part of the world’s energy future.
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The Role of SMR in Hydrogen Production
The majority of hydrogen is produced from unabated fossil fuels, most often natural gas. Steam methane reforming (SMR) combines natural gas with heated water to produce H2.
For every ton of hydrogen produced via this method, however, almost 12 tons of CO2 are released into the atmosphere. This process accounts for almost 2 % of global greenhouse gas emissions each year, highlighting its extremely unsustainable nature.
Electrolysis is a much more sustainable option. This process uses electrical charge to split water into oxygen (O2) and H2, allowing the production of clean 'green hydrogen' using only wind or solar power. This industry is still emerging, however, and it is expected to take time to build global electrolyzer capacity.
In contrast, "blue" hydrogen offers a practical and immediately actionable solution in the race to meet emissions targets.
New Technologies and Opportunities
Blue hydrogen produces the gas from fossil fuels while also using carbon capture utilization and storage (CCUS) to help limit emissions. This approach is compatible with conventional SMR, making it easier to incorporate into existing production plants.
New technologies are also being explored, including autothermal reforming (ATR). ATR is a similar approach to SMR, but instead introduces O2 to burn part of the feedstock to provide energy.
Combining ATR with CCUS could achieve higher energy efficiency while simplifying the production process and reducing investment costs. This process can capture 99 % of carbon emissions, but it is not entirely net-zero.
The use of O2 as a feedstock opens new and potentially beneficial avenues for ASUs. This technology works by dividing atmospheric air into its primary components, including O2, argon (Ar), and nitrogen (N2). The cryogenic distillation process remains the predominant method for this approach, producing high-quality, high-volume gaseous and liquid products.
Challenges of Hydrogen Integration
There are several challenges associated with integrating H2 production, particularly regarding purity and safety. For example, fuel cell applications require extremely high purity levels that often exceed 99.97 %, because even trace contaminants can significantly affect fuel cell performance.
Precise gas analysis is key to the accurate detection and quantification of a range of impurities, including O2, N2, sulfides, and carbon monoxide (CO). Hydrogen’s flammability also means that robust safety measures must be in place, including reliable leak detection and inerting systems designed to prevent combustion risks.
Safety and environmental regulations also continue to develop, with industries required to adhere to increasingly stringent standards. This necessitates the continuous monitoring and analysis of key parameters such as gas purity and emissions. Product quality must also be ensured, energy use must be optimized, and compliance must be demonstrated throughout the process.
Advanced gas analysis solutions are key to overcoming these challenges, with high-accuracy analyzers able to detect trace impurities to ensure that H2 meets even the most stringent purity requirements.
Continuous monitoring systems enable quality control, process optimization, and regulatory compliance via the provision of real-time data. Implementing these solutions allows industries to integrate effective hydrogen production, achieving high-purity H2 with safe and efficient operation, while maintaining compliance with all applicable standards.
Case Study: Analysis Enabling Zero-Carbon Steel Production
Hydrogen has significant potential to help decarbonize the steel-making industry. Coke is high-carbon coal that has been purged of volatile compounds, and this remains fundamental to the traditional blast furnace-basic oxygen furnace (BF-BOF) process.
Coke produces CO while providing heat to melt the iron ore, and this CO reacts with the ore to produce crude iron (Fe). The iron is transferred to another furnace, where O2 combines with some of the carbon in the Fe. While this approach results in the production of low-carbon steel, its high emissions of 1.73 tons of CO2 per ton of steel (including both process and combustion) mean this process is highly unsustainable.
Hydrogen can replace coke as both an energy source and a reducing gas. Reliable gas measurement is key to revolutionizing this process.
A groundbreaking project was looking to utilize a giga-scale hydrogen plant that was entirely powered by renewable energy sources, including hydropower and wind.
Instead of using the conventional BF-BOF process to create steel, this facility had opted to utilize green hydrogen produced at the site, essentially transforming the reduction reaction:
- Traditional process: Coke + iron ore = Fe + CO2
- New green process: H2 + iron ore = Fe + H2O
This innovative process is referred to as ‘H2 direct reduction of iron’ (H2 DRI) and can be used to produce iron that can subsequently be turned into steel, eliminating CO2 emissions.
Working Together to Optimize Production
Servomex had been successfully partnering with the steel and iron company behind the project for more than 40 years. Because of this longstanding collaboration, Servomex was asked to provide the high-performance gas analysis technologies necessary to ensure the efficiency, reliability, and safety of the H2 systems utilized in the DIR process.
The company’s SERVOTOUGH 2500 analyzers have been specifically designed for the analysis of toxic, corrosive, and flammable gas streams. These gas analyzers measure CO and CH4 concentrations to ensure optimized reduction process performance.
The SERVOTOUGH Oxy 1900 analyzers utilize the company’s Paramagnetic sensing technology to deliver the stable, reliable percentage O2 measurements needed to maintain process efficiency and safety.
This solution seamlessly combined with the company’s proprietary and third-party technologies by integrating with complementary sampling systems into a single analyzer house, delivering comprehensive gas monitoring and analysis capabilities.
Acknowledgments
Produced from materials originally authored by Servomex Group Limited.
This information has been sourced, reviewed and adapted from materials provided by Servomex.
For more information on this source, please visit Servomex.