焦化行业高污染排放对中国空气质量的影响

Effects of high pollution emissions from coking industry on ambient air quality in China

为了解焦化行业对中国大气的影响,以地级市为单位收集产焦量等活动水平数据,采用排放因子法建立了我国2020年焦化行业大气污染物的排放清单,并对2021年焦炭产量在1000万t及以上的省份焦化区和非焦化区6种常规污染物的浓度、超标率、作为首要污染物出现的频率和空气质量指数等情况进行了对比分析.结果显示,焦化行业大气污染物的高排放区主要集中在我国山西、陕西、河北、内蒙古、山东等省份(自治区),陕西省榆林市排放量最高.焦化区PM2.5和PM10的年均浓度(37.7μg·m^(-3)和82.7μg·m^(-3))、超标率(9.78%和9.26%)和作为首要污染物出现的频率(17.82%和35.97%)均高于非焦化区的年均浓度(32.0μg·m^(-3)和64.6μg·m^(-3))、超标率(7.46%和6.74%)和作为首要污染物出现的频率(17.00%和22.33%),SO2在两个地区均未超标,O3仅在焦化区的夏季超标,而NO2和CO仅在焦化区和非焦化区的个别城市超标.焦化区国标空气质量指数(AQI)、总AQI(AAQI)和基于健康风险的AQI(HAQI)在各个季节的均值均高于非焦化区,AAQI对污染的变化更敏感,HAQI对环境空气质量的要求更为严格.

In order to uncover the effect of coking industry emissions on the air quality in China,the emission inventory of air pollutants from coking industry on a prefectural level in 2020 was established based on the coking activity data of coke production amounts and emission factor.Then,the concentrations,over-standard rates,frequencies of occurrence as the primary pollutant,and air quality index in 2021 between coking and non-coking areas in the provinces with over 10 million tons of coke production were compared.The results showed that the high emission areas of air pollutants from coking industry were mainly located in Shanxi,Shaanxi,Hebei,Inner Mongolia,and Shandong Province in China,and the emission amount of Yulin in Shaanxi Province ranked first in the prefectural regions.The annual average concentrations(37.7μg·m^(-3)and 82.7μg·m^(-3)),over-standard rates(9.78%and 9.26%),and the frequencies of occurrence as primary pollutants(17.82%and 35.97%)for PM2.5 and PM10 in the coking area were higher than annual average concentrations(32.0μg·m^(-3)and 64.6μg·m^(-3)),over-standard rates(7.46%and 6.74%),and the frequencies of occurrence as primary pollutants(17.00%and 22.33%)in the non-coking area.SO2 did not exceed the national standard in both the coking and non-coking area,while O3 only exceeded the standard in the coking area in summer.NO2 and CO exceeded the standard only in a few cities in both the coking and noncoking area.The average values of the Air Quality Index(AQI),Aggregate Air Quality Index(AAQI),and Health-risk Based Air Quality Index(HAQI)recorded in all seasons were higher in the coking area than in the non-coking area.Further study found that AAQI was more sensitive to pollution change and HAQI was more stringent for ambient air quality.