In a significant advancement for the renewable energy sector, researchers have tackled a persistent challenge in biomass combustion: the problematic accumulation of ash and alkali metal components that can severely hinder boiler efficiency. This breakthrough comes from a study led by Tongyu QIU at the College of Energy and Environment, Shenyang Aerospace University, which has developed a sophisticated model to predict ash deposition and fouling in biomass-fired boilers.
Biomass is increasingly recognized for its potential as a clean energy source, particularly due to its zero CO2 emissions when burned. However, the high alkali content in biomass fuels often leads to the formation of a viscous deposition layer on the heating surfaces of boilers, which can trap fly ash and exacerbate slagging—a condition that disrupts operations and reduces efficiency. QIU’s research, published in ‘Meitan xuebao’ (Journal of the Coal Industry), addresses this issue head-on.
The team utilized FactSage software to calculate the adhesion characteristics of the initial deposition layer in the mid-temperature superheater of a biomass boiler. By integrating this with a critical velocity model, they established a comprehensive framework that accounts for both KCl condensation and fly ash capture. “Our findings indicate that the mass of KCl direct condensation accounts for 5.41% of the total deposition mass, while fly ash viscous capture contributes a significant 19.24%,” QIU explained. This insight is crucial for operators looking to optimize boiler performance and minimize maintenance costs.
Interestingly, the research revealed that while increasing wall temperature has a minimal effect on ash impaction efficiency, it is the flue gas inlet velocity that plays a pivotal role. Larger fly ash particles (50-80 μm) showed increased impaction efficiency with higher gas velocities, while smaller particles (10 μm) were more readily captured by the viscous surfaces. This nuanced understanding of particle behavior in relation to operational parameters opens the door for targeted strategies to mitigate fouling in biomass boilers.
The implications of this research extend beyond technical adjustments. As the energy sector increasingly pivots towards renewable sources, ensuring the efficiency and reliability of biomass systems is paramount. By effectively addressing ash deposition and slagging, this study not only enhances operational efficiency but also supports the broader transition to sustainable energy solutions. “Our model is a step towards making biomass a more attractive option for power generation,” QIU noted, emphasizing its potential impact on energy policy and investment.
As the energy landscape evolves, research like that of QIU and his team will play a crucial role in shaping the future of biomass technology. The ability to predict and manage fouling in biomass boilers could lead to more widespread adoption of this renewable resource, ultimately contributing to a cleaner, more sustainable energy future. For more information on this research and its implications, you can visit the College of Energy and Environment at Shenyang Aerospace University.
