TY - JOUR
TI - Study on multiple mechanisms and contribution weights of slagging in biomass-fired boiler
AU - Sun Yuting
AU - Sun Jinyu
AU - Ma Daoyang
AU - Qiu Tongyu
AU - Zhu Yiming
AU - Yang Shunzhi
AU - Wang Xuebin
JN - Thermal Science
PY - 2026
VL - 30
IS - 1
SP - 657
EP - 667
PT - Article
AB - To address the serious slagging issue in biomass boilers, field sampling, compositional analysis and corresponding FactSage thermodynamic calculations were conducted to study the slagging characteristics of a straw/bark-fired grate boiler. In addition to clarifying the multiple mechanisms, including the initial deposition by gaseous condensation and the fly ash capture by the viscous initial layer, the contribution weights of various mechanisms to the slagging behavior in four superheater areas were also obtained. Results indicate that K/Na double sulfates, rather than regular alkali sulfates, play a key role in forming the initial layer by condensation in high-temperature superheater. In 2nd mid-temperature super-heater, the condensed KCl and less sulfate form high-viscosity initial layer, which captures fly ash easily and results in serious slagging. The composition evolution during slagging process simulated by FactSage indicates that low temperature eutectics formed at high temperature area are more easily captured by the initial layer of high temperature superheater. The sulfates of K and Na start to combine below 950℃ and completely form K3Na(SO4)2 at 750°C. The K-Ca double sulfates exist above 850℃, while below 750℃ completely decompose into K2SO4and CaSO4. The gaseous condensation deposition contributes over 45% in the slagging of high/mid-temperature superheater, and only 8.4% in low temperature super-heater. The results provide a basis for the slagging prediction and prevention in biomass-fired grate boiler.
DO - 10.2298/TSCI250328141S
ER -