燃煤烟气水分回收和颗粒物同时脱除的实验和数值模拟

Experimental and numerical simulation of water recovery and particulate matter simultaneous removal from coal-fired flue gas

我国水资源匮乏、环保要求日益增强,开展燃煤烟气水分回收与颗粒物协同脱除具有十分重要的意义。本文搭建了烟气水分回收实验系统并建立了数值模拟模型,研究了不同因素对收水率和传热系数的影响,发现影响收水率的主要因素为烟气速度和烟气温差,烟气速度3m/s、烟气温差13.2℃时,收水率为51.77%;影响传热系数的主要因素为烟气速度和烟气与换热管壁面的过冷度,烟气速度9.6m/s、冷却水温度35℃时,传热系数为274.84W/(m^(2)·K)。搭建了颗粒物协同脱除实验系统,发现当过冷度从0℃增加到4℃时,颗粒物脱除效率从3.07%增大到29.28%;烟气速度从1.4m/s增大到6.4m/s时,颗粒物脱除效率从29.28%降低至7.40%。

Due to the scarcity of water resources and the increasing emphasis on environmental protection,it is of significance to carry out the investigation on the recovery of water from the coal-fired flue gas and the co-removal of particulate matter.In this study,an experimental system for flue gas moisture recovery was constructed,and then a numerical simulation model was developed.The influences of different factors on the water collection rate and heat transfer coefficient were investigated.It was found that the main factors affecting the water collection rate were the velocity of the flue gas and the temperature difference.When the flue gas velocity was 3m/s and the temperature difference was 13.2℃,the water collection rate was 51.77%.The main factors affecting the heat transfer coefficient were the velocity of the flue gas and the subcooling of the flue gas at the heat transfer tube wall.When the flue gas velocity was 9.6m/s and the cooling water temperature was 35℃,the heat transfer coefficient was 274.84W/(m^(2)·K).Moreover,an experimental system for particulate matter removal was constructed.It was found that when the subcooling temperature increased from 0℃to 4℃subcooling,the efficiency of particulate matter removal increased from 3.07%to 29.28%.When the flue gas velocity increased from 1.4m/s to 6.4m/s,the efficiency of particulate matter removal decreased from 29.28%to 7.40%.