大气混合冷凝器的优化设计

Optimum Design of Atmospheric Mixing Condenser

大气混合冷凝器是多效蒸发系统真空获得的关键设备,它对末效二次蒸汽的冷凝效果与生产强度密切相关。基于水蒸气的完全冷凝条件、喷头的抽汽和雾化性能等理论,围绕强化汽液传热和降低流体阻力,提出了大气混合冷凝器的优化设计方案。并以该方案对真空制盐四效蒸发系统的大气混合冷凝器进行了改造。运行结果表明,冷凝器改造前后二次蒸汽管进入冷凝器的真空度由-0.086 MPa提高至-0.089 MPa,二次蒸汽管的温度下降了6℃,即系统的有效温差增加了6℃,产量提高了11.1%,节能效益显著。同时对该真空系统实际运行过程中存在的问题进行了分析,并提出了对策措施。

Atmospheric mixing condenser is the key equipment in multi-effect evaporation system for obtaining vacuum condition.Its condensation effect for secondary steam at final stage is closely related to production efficiency.Based on the theories of fully condensing conditions,and extraction and misting properties of nozzle,and with respect to enhancing vapor-liquid heat transfer and reducing fluid resistance,the optimization design plan of atmospheric mixing condenser was proposed,which has been applied to atmospheric mixing condenser＇s transformation in a four-stage evaporation vacuum salt system.The practical results showed that vacuum degree of the secondary steam at the entrance of condenser is increased from-0.086 MPa to-0.089 MPa,and the corresponding temperature decreased by 6 ℃.It means that the effective temperature difference in the system is increased by 6 ℃,which results in significant increase in production by more than 11.1％ and great energy efficiency.Meanwhile,in this article,the problems during the actual operation of the vacuum system were analyzed,and then the corresponding countermeasures were proposed.