Abstract: Cooling seawater is used generally in petrochemical industry, power generation and shipping, however crystallization fouling of seawater would deteriorate heat transfer and increase energy consumption. The experiments of crystallization-fouling by seawater were conducted under static condition. The crystallization fouling composition was analyzed by XRD, and the results showed that seawater fouling was CaSO₄·2H₂O and Mg(OH)₂. A crystallization-fouling growth model was proposed as m=ke^-bt+M₀, and the experimental data of different roughness metal at 80℃ was fitted to the correlation with maximum relative error of 15.7%. The crystallization-fouling correlation and the growth curve showed that induction period, growth rate and mass of seawater crystallization-fouling were closely related to fouling-ions properties, super-saturation and metal surface roughness. When roughness of metal decreased, induction period of crystallization fouling became longer and grown rate became lower.

Key words: crystallization, fouling, kinetic modeling, seawater

摘要： 海水冷却水广泛应用于沿海地区的石油、化工、电力和船舶领域,但是海水容易引起严重的析晶结垢,从而降低换热效率和运行能耗。本文对海水析晶污垢的形成过程进行了静态实验研究,通过XRD分析了海水析晶污垢的组成,结果显示污垢主要成分为CaSO₄·2H₂O和Mg(OH)₂。本文提出了海水析晶污垢的生长模型,推导了污垢生长曲线关联式m=ke^-bt+M₀,拟合了80℃时不同表面粗糙度试片的海水析晶污垢生长关联式和生长曲线,拟合最大相对误差15.7%。海水析晶污垢生长关联式和生长曲线显示,海水析晶结垢的诱导期、污垢生长速率和结垢量与海水中成垢离子的晶体生长活化能、过饱和度以及换热试片的表面粗糙度有关,试片的粗糙度越小,海水析晶结垢的诱导期越长,生长速率越慢。

关键词: 结晶, 结垢, 动力学模型, 海水