Aiming at the two main mechanisms of initial deposition layer of ash deposition

namely

condensation and thermophoresis mechanism

a mathematical model for the formation of initial deposition layer by K-containing species was established. The rationality of the model was validated by the experimental results in the literature which indicates that considering the changes of the thickness of the deposition layer and the surface temperature have a reasonable improvement. The model was used to study the deposition process of K-containing gas and aerosol particles on the heating surface

and to investigate the effects of K-containing species composition

flue gas temperature and velocity. The results show that

because of the difference in the relative concentrations of K-containing gas and aerosol particles

both condensation and thermophoresis deposition may play a major role in the formation of the initial deposition layer at the beginning of the deposition process

while thermophoretic deposition dominates the later stage. The effects of flue gas temperature and velocity on the deposition process is similar

that is

the higher flue gas temperature and velocity

the higher the initial deposition rate

the lower the later deposition rate

and the lower the thickness of the deposited layer.