In order to compare models for potassium release during biomass combustion, codes of several typical evaporation and kinetic models were written to calculate the release rate of potassium. Calculation results were analyzed in comparison with the thermogravimetric analysis of ashes from agro-stalks. It shows that: (1) Predictions from evaporation model and Zhang/Cao’s kinetic models agree better with potassium release in respect of temperature than the others. (2) The maximum release rate of potassium in Peters’ model occurs at much lower temperature, while that in Fatehi model occurs at much higher temperature than experimental results. (3) A good agreement is obtained between the evaporation model and experiment (relative error <20%), When temperature increases to 900 ℃ at high heating rate (30/50 ℃/min). The physical mechanism of the evaporation model is clear, but the simulation is considerably larger than the experiment because of the neglect on interaction of potassium salts. (4) The kinetic models and experiments indicated that the effects of potassium content in straw and heating rate are greater than that of final temperature on the release rate of potassium at 900-950 ℃.
Su Xianqiang, He Fang, Li Xiuhua, Gao Zhenqiang.
COMPARISON OF MODELS FOR RELEASE OF POTASSIUM DURING AGRO-STALKS COMBUSTION[J]. Acta Energiae Solaris Sinica. 2022, 43(5): 391-398 https://doi.org/10.19912/j.0254-0096.tynxb.2020-0775
中图分类号:
TK6
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