Decarbonisation Technology August 2026 Issue

shutdowns. Since commissioning, these PPS- GR-based heat exchangers have demonstrated significantly longer service intervals, stable operation under challenging flue gas conditions, and improved heat recovery performance. In practice, this means less corrective maintenance and more predictable plant operation. Larger-scale applications confirm the same trend. In one project, a 4.6 MW economiser replaced a conventional heat exchanger that had repeatedly suffered from corrosion-related damage and required full replacement. Since the retrofit, the PPS-GR-based system has operated reliably without comparable maintenance issues, demonstrating that the material concept can be transferred from compact units to multi- megawatt heat recovery systems. Beyond durability, operators report practical advantages that are highly relevant for daily plant operation: reduced fouling tendencies, easier cleaning procedures, and improved availability during operating campaigns. These results are important because they show that the business case is not driven by heat recovery alone. Long service life, reduced maintenance effort, and reliable operation under real plant conditions are equally decisive for making low-temperature flue gas heat recovery economically viable. Contribution to industrial decarbonisation The recovery of low-temperature waste heat below the acid dew point contributes directly to industrial decarbonisation by improving overall efficiency and reducing reliance on fossil fuels. From a system perspective, it transforms previously unused thermal energy into a resource that can substitute primary energy demand. The scale of this opportunity is substantial. In Germany alone, the national waste heat platform has registered more than 24,000 waste heat potentials from more than 3,000 companies, amounting to 205 TWh per year ( Bundesstelle fur Energieeffizienz, 2026 ). At the European level, the sEEnergies project identified around 118 TWh per year of industrial excess heat available at 95°C and around 267 TWh per year at 25°C from major industrial sites, corresponding to roughly 4% and 9% of EU industrial final energy demand (F leiter, et al., 2020 ). If this recovered heat replaced fossil heat, the CO₂ savings would be significant: roughly

24-40 million tonnes per year for the 118 TWh potential, or 54-91 million tonnes per year for the 267 TWh potential, depending on whether natural gas or coal is displaced ( Our World in Data, 2025 ). In district heating applications, recovered heat can replace heat generated by fossil boilers. The same European analysis indicates that industrial excess heat available within a 10 km range could supply around 8% of current EU-28 district heating demand at 95°C, underlining the role of heat networks as a key route to market. Importantly, these benefits can often be realised without fundamental changes to the core process. As a retrofit solution, corrosion- resistant heat recovery offers a pragmatic and scalable pathway to reduce emissions in existing plants and make low-temperature flue gas heat recovery a directly deployable measure for industrial decarbonisation. Low-temperature waste heat from industrial flue gases has long been treated as an unavoidable stack loss. The reason was not a lack of energy potential but the difficulty of recovering this heat reliably below the acid and water dew point. Corrosion-resistant heat transfer materials change this boundary. They allow flue gases to be cooled into a temperature range where additional sensible and latent heat from water vapour condensation can be recovered, while maintaining long service life in corrosive environments. This opens a practical pathway for industrial decarbonisation. Recovered heat can support district heating networks, reduce fossil heat generation, improve the energy balance of carbon capture systems, and increase the efficiency of existing industrial assets. Conclusion: Unlocking a previously inaccessible energy source By turning previously inaccessible stack losses into useful low-carbon heat, corrosion-resistant heat recovery can become an important enabling technology for more efficient and resilient industrial energy systems. VIEW REFERENCES Dr Nicolas Schiffer Fiedler Nicolas.Schiffer@technoform.com