关键词:

清洁传热, 循环流化床, 脱硅, 结垢, 结垢模型

Abstract: To solve Scaling problem, the scale formation and cleaning/prevention of desiliconization heat exchanger with liquid-solid circulating fluidized bed was investigated. The result showed that silica sediment-scaling curve was asymptotic with about 2.5 h induction period. The scaling mechanism was crystallization scaling combined with particulate scaling. When the particular inert solid particles were introduced into the heat exchanger to form liquid-solid circulating fluidized bed, the scaling layer deposited on heat transfer surface could be removed quickly and scale formation could be prevented completely, hence cleaning heat transfer was realized. The rate of the scale cleaning increased with the increase of fluid velocity and inert solid particle concentration. The scaling mechanism was not affected by inert solid particles. Based on the analysis of scale prevention mechanism of liquid-solid fluidized bed heat transfer, a mathematical model for silica sediment scaling was proposed. The predicted value of scaling model is in good agreement with experimental data.

Key words:

清洁传热, 循环流化床, 脱硅, 结垢, 结垢模型