典型重化工园区产能增加对城市O_(3)浓度影响

The impact of increased capacity at a typical petrochemical industrial park on ambient O_(3) in surrounding cities

重化工园区产能增加将加大园区挥发性有机物(VOCs)排放总量,进而影响本地及周边城市O_(3)浓度.珠三角实施的“VOCs倍量替代”政策可在城市层面有效抵消重化工园区VOCs排放量上升的不利影响,还可进一步降低城市VOCs排放总量,实现区域O_(3)浓度下降.以惠州市某大型重化工园区为例,编制2018—2020年重化工园区产能增加以及实施“VOCs倍量替代”政策的污染物排放清单,基于WRF-CMAQ模拟体系,定量分析多种情景下园区在基准年(2017年)7—10月气象条件下对惠州市及周边城市O_(3)影响程度.研究表明,重化工园区增产而增加VOCs排放4101.96 t,“VOCs倍量替代”综合减排余量7298.97 t;“VOCs倍量替代”政策可有效解决重化工园区增产对O_(3)浓度的不利影响,其中7月最为显著,主导东南风下风向的深圳市及惠州市大亚湾管委会站点O_(3)浓度降幅最大,分别为3.9μg·m^(-3)(下降率2.97%)和7μg·m^(-3)(下降率4.95%);7—10月平均对惠州市O_(3)浓度降低贡献为0.96μg·m^(-3)(下降率0.53%),对周边市深圳市、东莞市、汕尾市O_(3)浓度分别降低1.39μg·m^(-3)(下降率0.99%)、0.33μg·m^(-3)(下降率0.2%)、0.3μg·m^(-3)(下降率0.22%),对广州市和汕尾市影响可忽略不计.

Increased capacity in petrochemical industrial park leads to the significant rise in VOCs emissions,accordingly aggravating the O_(3)pollution in local and surrounding cities.In the Pearl River Delta region,the well implement of"VOCs multiple substitution"policy can effectively offset the adverse impact of rising VOCs emissions in petrochemical industrial parks by reducing the total amount of VOCs emissions at the city scale,thereafter lowering the regional O_(3)concentration.Taking a petrochemical park in Huizhou City as typical case study,we compiled the emission inventories of increased capacity and the implementation of"VOCs multiple substitution"policy during 2018 to 2020.With the developed emission inventories,the impacts of the petrochemical industrial park on O_(3)concentrations under the meteorological conditions from July to October in the base year(2017)were then quantified using WRF-CMAQ.The results showed that,7298.97 tons of VOCs were ultimate reduced attribute to the policy-implement of"VOCs multiple substitution",although the increased capacity of the petrochemical industrial park brought 4101.96 tons of VOCs emissions.The simulation results proved that the policy of"VOCs multiple substitution"can effectively mitigate the adverse effect of the increased capacity in petrochemical industrial park on O_(3)concentration.In July,the reduction of O_(3)concentrations were maximum in Shenzhen and Guanweihui monitor station,with the reduction concentration at 3.9μg·m^(-3)(with a decline rate 2.97%)and 7μg·m^(-3)(with a decline rate 4.95%),respectively.This was because their locations were in the downwind of the dominant wind direction of the southeast in July.From July to October,the average reduction contribution of O_(3)in Huizhou,Shenzhen,Dongguan and Shanwei were 0.96μg·m^(-3)(with a decline rate 0.53%),1.39μg·m^(-3)(with a decline rate 0.99%),0.33μg·m^(-3)(with a decline rate 0.2%)and 0.3μg·m^(-3)(with a decline rate 0.22%),respectively,while the contribution to O_(3)concentration reductions in Guangzhou and Shanwei were nearly neglectable.