Energy from biomass corresponds to more than 60% of all renewable energy sources in Europe and is currently the most widely used worldwide. Recently, the Paris Agreement in the 21st Conference of the Parties for global climate change (COP21) set the objective of global electricity production in 2050 will be almost entirely based on zero-carbon emitting technologies, so biomass energy will contribute to that objective and significantly reduce dependence of fossil fuels. However, currently biomass plants have not reached the efficiency that can be obtained with fossil fuels, mainly due to severe corrosion caused by alkali metals, chlorine and other corrosive elements, resulting in a shorter boiler components lifetime, so maximum temperatures and steam pressures are limited, which translates into lower overall efficiency and profitability. Moreover, biomass feedstock is increasingly diverse and there is a need for generic understanding of the associated corrosion risks. Today’s dominant bioenergy source is clean wood, it is expected that the share of lower cost, but more corrosive waste will increase in the future.
The BELENUS project was conducted from March 2019 until February 2024 and was funded within the H2020 program of the European Commission. BELENUS aimed at will reduce bioenergy CAPEX and OPEX through a holistic approach to prevent mainly corrosion in the boiler, in particular in superheater tubes: a) new surface engineering: biomass corrosion highly resistant coatings on creep resistance materials; b) new strategies of welding and bending for coated tubes improving the quality and efficiency of boiler components; and c) new online corrosion monitoring system specifically designed for biomass CHP plants. The project brought together a broad consortium formed of industry partners, SMEs, universities and research institutions of the biomass and materials science sector.
The new coatings, the new welding and bending strategies of the coated tubes and the corrosion monitoring system will allow raising biomass plants efficiency by increasing the operating temperature resulting in reducing the fuel expenditure and providing flexibility by allowing the use of different types of biomasses, as well as the lifetime of critical components of biomass fired boilers.
The validation tests of the new materials and developments involved lab scale, pilot plant and real plant exposure. Modelling and lifetime prediction tools and cost and life cycle analysis were undertaken so the optimum materials and coatings have been chosen from the durability, economic and environmental perspectives, maximising the sustainability in economic and environmental terms.
