空气预热温度对燃烧状况的影响

空气预热是有效的节能技术,但预热温度的提高同时带来NOx排放浓度增加的问题。为了了解其规律,本文针对某烯烃厂芳烃加热炉的空气预热改造项目,对不同空气预热温度情况下的燃烧状况和NOx排放规律做了研究。首先利用数值模拟方法,构建了加热炉三维几何模型,将燃烧模型和NOx生成模型结合,对不同空气温度下的燃烧温度和NOx排放进行模拟,对炉膛内部温度分布及NOx排放规律做了研究,最后找出空气预热最佳温度。

The numerical simulation of preheated air temperature on combustion process

The preheating air combustion is a technology of saving energy effectively,however,NOx emission also increases as a function of exponent with the increasing of the preheated air temperature.Aimed at clarifying the relation of them.On the reconstructing a set of air pre-heater project to the heat furnace in some Olefin Plant,the numerical simulation of the influences of preheated air temperature on combustion process with the NOx emission was carried out.The 3D geometry model of the heat furnace was fulfilled at first,and then the numerical simulation combined with the combustion model and NOx model was performed to display the temperature distribution and NOx emission in the hearth on the different preheated air temperature,and finally the best preheated air temperature was presented.