424 / 2018-12-27 14:02:10

上喷淋上进气喷淋塔传热性能数值研究

烟气除湿，喷淋塔，数值模拟，正交实验法

全体主题 > 数值模拟、建模与CFD

随着湿法烟气脱硫工艺在燃煤电厂的普及，脱硫后的烟气含湿量大大增加，变成饱和湿烟气 。饱和湿烟气经烟囱排放后，与温度较低的空气接触后会形成 “湿烟羽”现象，造成明显的视觉污染。针对湿法脱硫烟气含湿量过高的问题，本文提出了一种基于上喷淋上进气的喷淋系统，通过CFD数值模拟进行了正交模拟实验，研究了操作因素对实验的影响，并分析了喷淋液滴直径、喷淋液滴速度、喷淋流量、喷淋角度和喷淋高度五个因素与评价指标（喷淋塔塔效率和烟气出口液滴逃逸率）之间的关系。通过极差分析，得到了不同评价指标的最佳运行条件。分析发现，喷淋液滴直径、喷淋液滴速度和喷淋流量是影响塔效率的主要因素，喷淋角度和喷淋高度是影响逃逸率的主要因素。通过趋势分析，讨论了不同操作因素对塔效率和逃逸率的影响。本文的研究结论为其他类型喷淋塔的传热性能优化提供了参考。
Numerical study on the thermal performance of a novel spray tower with upward spraying and downward gas flow
With the popularization of wet flue gas desulphurization technology in coal-fired power plants, the moisture content of flue gas after desulphurization increases greatly and becomes saturated wet flue gas. When the saturated wet smoke is discharged through the chimney, it will form "wet smoke plume" after contacting with the air with lower temperature, causing obvious visual pollution. To solve the problem of high moisture content for flue gas wet desulphurization technology, this paper puts forward a kind of novel spray system with upward spraying and downward gas flow, and orthogonal simulation experiment was carried out by CFD numerical simulation, the influence of operation factors on experiment was studied, and the relationship between the five factors of droplet diameter, droplet velocity, droplet flow rate, spray angle and spray height and the evaluation index (spray tower efficiency and droplet escape rate at flue gas outlet) was analyzed. Through the range analysis, the optimal operating conditions for different evaluation indicators were obtained. It is found that the diameter, speed and flow rate of the spray droplets are the main factors affecting the efficiency of the tower, and the angle and height of the spray are the main factors influencing the escape rate. Through the trend analysis, the effects of different operational factors on tower efficiency and escape rate are discussed. The conclusion of this paper provides a reference for the heat transfer performance optimization of other spray towers.
Key words: flue gas dehumidification, spray tower, numerical simulation, orthogonal experimental method