The fuels used to operate biomass power plants cause corrosion and erosive wear in boilers. In fact, biomass can release contaminants, such as alkali metals, chlorine, sulfur, and other corrosive chemicals, when burned. As a result, regular maintenance is fundamental to maximize the lifespan and reliability of equipment in these power stations as well as ensure plant availability, performance, and efficiency.
The key piece of equipment at Lisahally plant is the two-pass biomass grate boiler, which generates high-temperature, high-pressure steam by combusting the wood-based material fed to its furnace. The steam is then transferred to a turbine, coupled with a generator to produce electricity. Waste steam is condensed into water and fed back to the boiler via a closed-loop system.
As corrosion and erosion were affecting the integrity of Lisahally Power Stations heat exchange system, i.e. boiler furnace and wall tubing, plant managers contacted Sulzer to help them conduct the necessary repair work.