Decarbonisation Technology May 2022 Issue

Flue gas analysers for safe combustion of high hydrogen fuels Proper flue gas monitoring is critical to ensure safe combustion control, fuel efficiency, and reduced emissions, especially when firing high hydrogen fuels

Tim Tallon AMETEK Process Instruments

A midst the global transition to across many industries, including power and steam generation, oil, gas and cement production. While many companies have shifted to using natural gas in their burners to reduce their emissions to air, there is still the opportunity to decarbonise further by using hydrogen as a zero-carbon fuel – either by spiking it into the natural gas header or by using pure hydrogen as the primary fuel source. In the transition to high hydrogen fuels, it will become increasingly important to monitor the stack gas and flue gas to ensure plant safety and efficient combustion control. Challenges decarbonising combustion and trends driving use of high hydrogen fuels Now more than ever, end users are confronted with the challenges of retrofitting their plants to meet evolving environmental and regulatory targets. Operators of combustion equipment have many options available to meet their long-term decarbonisation targets, including: • Carbon capture to directly remove carbon decarbonised assets, combustion remains an important heating source emissions from the combustion process • Electrification to generate heat in place of combustion • Hydrogen fuels to generate heat without carbon emissions While deciding how to decarbonise is circumstantial, investment costs play an inherently large role in the screening process, especially for very well-established plants. Operators considering carbon capture are faced with justifying the up-front investment and securing adequate plot space for the equipment.

In many cases, centralised processes that generate high carbon emissions are primed for carbon capture technology. However, operators face much more of a challenge if they are looking to remove carbon emissions from multiple decentralised combustion sources. In the case of a refinery, there would be considerable difficulty in the logistics of isolating stack gases from multiple fired heaters and then redirecting them to a single carbon removal system. Carbon capture is one option to decarbonise combustion processes, but it also poses a challenge with existing plants that have numerous small and decentralised stack emissions. In addition, while many operators may consider electrification to reduce their carbon emissions, it might not be feasible or practical in all cases. For new greenfield projects, electrification presents a viable option for many low-temperature applications, although this approach still depends on an outside mechanism to generate and supply sufficient renewable electricity. However, the real challenge with electrification enters when applying it at a larger scale across the wider installed base of existing plants and equipment. It may not be economical to buy all new electric equipment, especially if multiple In the transition to high hydrogen fuels, it will become increasingly important to monitor the stack gas and flue gas to ensure plant safety and efficient combustion control