Abstract:
Affected by the unfavorable topographical conditions and the massive residential coal combustion during heating season in winter, haze events occur frequently in the Guanzhong area of Shaanxi Province, China. The regional air quality has improved significantly since 2017 when the residential coal combustion control policies implemented. Based on the field investigation of the residential coal usage and local statistical data, the situation of residential coal control in 7 cities (districts) of Guanzhong area during the past four years (2017 ~ 2020) was evaluated. The PM
2.5 from residential coal combustion contribution to ambient PM
2.5 was estimated by Box model, and the health and economic benefits were evaluated by Poisson Regression model in this study. The results showed that residential coal has been effectively controlled in Guanzhong area during winter from 2017 to 2020, with the total reduction of 777,938.00 t. The reduction amount in Xi'an and Weinan were the highest, and the treatment rate reached 100% in Yangling District. The residential coal control decreased the daily average PM
2.5 concentration during heating season in Guanzhong by 7.2 μg·m
-3 and the contribution from resident coal sector to PM
2.5 decreased by 4.5% approximately in the past four years, which account for 12.4% of the PM
2.5 improvement. The premature mortality rate of residents decreased by 1.50E-05 (95% confidence interval (CI): 3.66E-06, 2.62E-05), with a reduction rate of 98.2%; the morbidity rate (incidence of outpatient, hospitalization and chronic bronchitis) decreased by 4.11E-04 (95%CI: 1.71E-04, 6.59E-04), with a reduction rate of 98.3%. The health benefit population was estimated to be 10,662 and the consequent economic benefit was estimated to be as high as 1.412 billion RMB from the residential coal control in the Guanzhong area, Shaanxi.