Fuel Quality Impact in a Historical Perspective: A Review of 25 Years of EU-Funded Research on Fuel Characterization, Ash and Deposit Formation, and Corrosion

Heating and cooling are responsible for approximately half of EU’s final energy demand, while biomass is currently responsible for more than 90% of all renewable heat. The goal is to increase share of biomass-based technologies, in the European heat market, from 11% in 2007 to about 25% in 2020 [RHC-Platform, 2014]. Combined Heat and Power (CHP) from biomass is a suitable technology for medium- and large scale units, where many utility and industrial applications can be found, especially in Scandinavia. The main challenge for efficient CHP and high temperature steam production from biomass are ash-related problems. Corrosion due to the difficult ash composition of biomass limits both steam temperature and efficiency. By solving these issues, large-scale boilers offer a huge potential for efficiency increase and emission reduction, during CHP generation at cost-competitive and environmental friendly conditions. In order to reach these goals, and to enable a secure and nearly carbon neutral heat and power generation, recently, the Biofficiency proposal, was granted under Horizon2020, aiming to:
Develop next generation, biomass-fired CHP plant, increasing the steamtemperatures up to 600°C, at medium to large scale (10 to 200 MWth).
Increase the efficiency of CHP plants by elevated steam temperatures throughsolving and understanding of ash-related problems – slagging, fouling andcorrosion.
Reduce emissions – i.e. CO2, particulates, CO, NOX, and SO2 – by efficiency gain,reduction of impurities and by intelligent plant design.
Broaden the feedstocks for pulverized fuel (PF) and fluidized bed (FB) powerplants, using pre-treatment methods with focus on the reduction of harmful,inorganic elements: Cl, S and the alkali metals.
Prevent power plant damage due to high-temperature Cl-induced corrosion.
Reduce costs for utilities due to increased efficiency, lowered emissions and fuelconsumption, decreased number of outages and maintenance due to handling ofash-related problems.