NO_(2)短期浓度和长期浓度随排气筒高度变化的差异性分析

The Differences Analysis on Short-term and Long-term Concentration of NO_(2) with Different Stack Height

本文采用《环境影响评价技术导则大气环境》(HJ 22—2018)推荐的预测模型AERMOD,研究了在不同排气筒高度时,NO_(2)短期浓度和长期浓度的差异性。结果表明,NO_(2)1 h平均质量浓度、日平均质量浓度和年平均质量浓度均随着排气筒高度升高而降低;排气筒高度越高,1 h平均质量浓度、日平均质量浓度和年平均质量浓度下降值越大。1 h平均质量浓度下降值的变化过程可分为三个阶段,日平均质量浓度和年平均质量浓度下降值的变化过程可分为两个阶段,各阶段均符合线性规律,且各阶段趋势线斜率随排气筒高度升高而降低。在本研究条件下,综合考虑环境影响和经济效益,排气筒最佳高度范围为29~30m。

Using the AERMOD model,which recommended by Technical Guidelines for Environmental Impact Assessment Atmospheric Environment(HJ 22—2018),the differences on short-term and long-term concentration of NO_(2) at different stack height were analyzed.The results showed that the average concentration of NO_(2) in 1 h,24 h,and a year decreased with the increasing of stack height.The higher the stack height was,the larger the decreasing value of the average concentration in 1 h,24 h,and a year were.The decrease value changing procedure of the average concentration in 1 h can be divided into 3 stages,and the decrease value changing procedure of the average concentration in 24 h and a year can be divided into 2 stages.The trend of decrease value was linear in every stage and the trendline slope decrease with the stack height.At the condition in this study,the best stack height was between 29~30 m based on the comprehensive consideration of environmental impact and economic benefits.