摘要
以二甲基甲酰胺生产中易于结垢的换热器冷却过程为研究对象,采用换热管内置弹簧并利用泵的开、停措施使流体产生脉冲流动的方法对换热器在线防垢除垢进行研究。采用测定换热管外冷却水的吸热量随时间的变化关系以及试验结束后管内污垢称重法研究内置弹簧脉冲流动法对换热器在线防垢除垢效果。研究了泵的开、停时间,内置弹簧长度等因素对防垢除垢的影响。结果表明:在试验装置上,内置弹簧长度175～198cm、泵运行时间5～10s、泵停止时间5s时,具有显著的防垢除垢效果,在试验装置运行4h除垢率高达92.9%。同时在此条件下装置运行4～12h内,污垢增长量较少,说明此法除垢效果稳定。实验研究结果对实际工业换热器的改造具有一定的参考意义和指导价值。
The fouling behavior of the mixed salts scale crystallized from the DMF（NN-dimethylformamide） solution during cooling in heat exchanger was investigated.The methods of inserting screw spring in cooling tube and using pulse flow by operating the feeding pump with running-stopping operation were adopted to prevent and clean up the fouling scale on the tube wall on-line.The variation of the heat transfer amount with the time prolongation of the experiments was obtained by measuring the temperature change of the cooling water at constant flow,and the total amount of the fouling scale,the crystallized mixed salts,was measured by weighting method.The effect of the inserted spring length,prolongations of pump running and stopping time respectively were studied.The results show that,in the experimental equipment with the inserted spring length of 175～198 cm,pump running time of 5～10 s and stopping time of 5 s,there is a remarkable anti-fouling effect;And in 4 hours heat transfer,the weight of fouling scale is decreased by 92.9% as compared with that of no inserted spring.At the same operating conditions,the weight of fouling scale changes only a little when the heat transfer experimental time are 4,8 and 12 hours,respectively,which means that the method of anti-fouling is stable and effective.
出处
《高校化学工程学报》
EI
CAS
CSCD
北大核心
2010年第5期893-896,共4页
Journal of Chemical Engineering of Chinese Universities
关键词
二甲基甲酰胺
换热器
内置弹簧
防垢除垢
脉冲流动
N
N-dimethylformamide
heat exchanger
inserted spring
anti-fouling
pulse flow
