In this fourth installment of a 14-part series of monthly articles, The Combustion Institute recognizes the 2017 Distinguished Papers selected from among the scientific papers presented during the 36th International Symposium on Combustion. Congratulations to Xin Yang, Derek Ingham, Lin Ma, Nanda Srinivasan, and Mohamed Pourkashanian for winning the DPA in the Diagnostics colloquium.
The authoritative paper, Ash deposition propensity of coals/blends combustion in boilers: a modeling analysis based on multi-slagging routes, has proposed a novel approach to build an ash deposition prediction model as an engineering tool to predict the likelihood of ash slagging and fouling in typical utility boilers. The scientific team based their model on the current understanding of ash deposition in boilers, taking into consideration sophisticated multi-slagging formation routes, incorporating more advanced thermo-chemical calculations, and crucial historical deposition and process data collected from various operational utility boilers. The developed model shows a high success rate in ranking the overall slagging propensities of typical U.S. coal blends.
Owing to market fluctuations of the world’s coal trade due to competition from a diverse energy mix and the associated environmental impacts of firing coal for power generation, many power plants are driven to incorporate aggressive low-grade coals and blends in their fuel mix or switch to co-firing biomass fuels. The chemical compositions of these coals and biomass fuel ashes can cause severe ash deposition issues due to slagging and fouling inside boilers. Uncontrolled ash deposition in a furnace can substantially reduce boiler efficiency and lead to unscheduled outages. Therefore, trending and understanding the fuel-related impacts on boiler performance and components is imperative for efficiency, dispatch optimization, and reliability. Improving the prediction of ash slagging propensity is of vital importance to power plants that plan to use low-cost aggressive fuels. Reliable prediction methods augment the ability of plant operators to be more proactive than reactive.
In the last decades, considerable progress has been made in understanding ash deposition mechanisms of various types of coals and biomass fuels. However, because of the complexity in the mechanisms behind the formation of slagging and fouling, most existing models only perform well for limited fuel types. For these reasons, a more reliable method for assessing slagging propensity of fuels is urgently needed to cover a wider range of fuels and take into consideration all major ash deposition pathways.
The scientific team’s research presented in the paper can directly benefit coal fired power plant operators and designers, equipment manufacturers, and coal and biomass fuel combustion researchers. The power industry can use the team’s research to rank and select suitable fuels to reduce the risk of fuel-related operational issues. Academic researchers can use the new method on fuel deposition to develop an improved understanding of the extremely complex slagging and fouling routes in utility boilers and explore solutions to minimize the impacts.
Power plant operators can use the scientific team’s research in the selection of new fuels or combinations of fuels to substantially reduce the risk of severe slagging in the boiler that may lead to unscheduled plant outages and subsequent consequences. The team’s research will enable power plant operators and researchers to predict and better manage the potential operational issues from ash deposition and maintain high efficiency of the boiler, and thus reduce the overall emission from the power stations.
Although similar ash deposition research has been built upon over the last 3 decades, the specific research presented in this paper was started in late 2013 and completed at the end of 2015. The scientific team’s work was based on strategic collaboration between the Energy 2050 initiative at the University of Sheffield, United Kingdom, and the Electric Power Research Institute (EPRI), United States. Researchers from the University of Sheffield developed the proposed methods and researchers/engineers from EPRI provided the comprehensive set of data and support of this research.
About 1,300 papers were submitted to the 36th Symposium in 14 combustion science colloquia. Those papers were categorized by teams of colloquium coordinators and co-chairs, and then distributed to approximately 1,000 scientific reviewers. One paper in each discipline was awarded the recognition of Distinguished Paper.
The 14 Distinguished Papers undergo committee review for consideration to receive the Silver Combustion Medal that will be awarded during the 37th Symposium in Dublin, Ireland. A paper selected for this honor exemplifies quality, achievement, and significance to advance a field of combustion science. Distinguished papers are selected biennially from among the scientific papers presented during the International Symposium on Combustion and accepted for publication in the Proceedings of The Combustion Institute.