【作者】 钟宏伟；

【导师】 张少峰；

【作者基本信息】 河北工业大学 ， 化学工艺， 2003， 硕士

【摘要】 本文从理论和实验两个方面较深入研究了汽液固多相流态化技术对换热管中硫酸钙溶液结垢的影响，探讨了三相循环流化床蒸发器的防、除垢机理，对其防除垢和强化传热性能做了进一步考察，针对固体颗粒对硫酸钙结垢诱导期的影响进行了研究，并与不加入固体颗粒的实验结果进行了比较，同时对结垢诱导期的确定方法进行了改进。 实验结果表明：惰性固体颗粒的加入不仅大大地延长了结垢诱导期，达到了防垢的目的，而且强化了传热，除垢效果明显。加入固体颗粒后的结垢诱导期要比未加颗粒的结垢诱导期延长将近5倍；加入固体颗粒浓度越大，传热效果越好；大粒径颗粒要比小粒径颗粒的传热效果好；加入的颗粒在较高速下要比低速情况下传热效果好。本文对结垢过程进行了理论分析，得出了不加固体颗粒和加入固体颗粒时硫酸钙结垢率的计算公式，数据显示，理论结果与实验结果比较吻合。更多还原

【Abstract】 In this paper, further studies were carried out for the influence of CaSO4 fouling in heating tube through vapor-liquid-solid three-phase flow state technology on theory and experiment. The mechanisms of preventing and removing fouling were discussed in the vapor-liquid-solid three-phase circulating fluidized bed. The capability of preventing and removing fouling and enhancing the heat transfer were further reviewed. The influence of induction period of CaSO4 fouling from vapor-liquid-solid three-phase flow state technology was studied, and the result was compared with that of experiment without particle. The decided way of the induction period of fouling has been improved.The experimental results show that the induction period of fouling can be prolonged by adding particles, and solid particle can prevent fouling and enhance heat transfer. The induction period of fouling was lengthens to be nearly 5 times with solid particle than without particle. The more add particles, the more the effect of heat transfer was good. The effect of heat transfer was better when the diameter of particles was bigger. The effect of heat transfer was better in high speed than low speed with adding particles. The experiential equation of CaSO4 rate of mass deposited with particles and without particles was obtained from theoretic analysis to fouling. The agreement between predicted and measured results is excellent.更多还原