In order to grasp the national emission trends, as a reference for regulation, the base year emission calculation is reviewed and conducted every three years to renew the national air pollutant emission inventory, and to update it partially over the years. The focus of this project is to estimate the new version of air pollutant emissions (TEDS 11.0) in the base year of 2019, and the main achievements are summarized as follows:
1.The establishment of the new version of the air pollutant emission inventory: The TEDS 11.0 version of the 2019 base year is completed, and it was officially announced on July 1, 2021. The scope of TEDS 11.0 covers point sources (regulated places), line sources (road vehicles), area sources (other stationary sources and off-road transportation), ammonia sources and biological sources. The main results of the point, line and area source inventory are summarized as follows:
(1)Point source: It is declared by counties and cities for a total of 14,643 sources, with priority given to the use of data from the declaration/air pollution fee database. The total emissions from the point sources in 2019 are 20,562 for TSP, 13,440 for PM10, 10,020 for PM2.5, 51,863 for SOX, 112,395 for NOX, 81,953 for THC, 67,975 for NMHC, 248,027 for CO and 18 for Pb in unit of Metric tons/year, which are mainly from power industries, base metal manufacturing, non-metallic mineral products manufacturing, electronic component manufacturing, etc.
(2)Line source: It is based on the results of the EPA's mobile source project. The total emissions from the line sources in 2019 are 28,175 for TSP, 18,934 for PM10, 14,977 for PM2.5, 111 for SOX, 150,867 for NOX, 104,536 for THC, 96,732 for NMHC, 307,967 for CO and 18 for Pb in unit of Metric tons/year, where the main sources are diesel heavy-duty-trucks, gasoline cars and four-stroke motorcycles.
(3)Area source: It covers the emission of hydrocarbons from industrial unregulated factories, commercial (such as cooking fume, hydrocarbons from general consumer goods) and residential emissions, agricultural open burning, garbage dumps, mining and agriculture operation, construction and road dust, wind erosion of bare ground, non-road transportation and other sources. There are 119 pollution sources in total. The total emissions from the area sources in 2019 (excluding offshore ships) are 252,910 for TSP, 85,036 for PM10, 22,118 for PM2.5, 14,513 for SOX, 30,848 for NOX, 380,847 for THC, 301,795 for NMHC and 301,107 for CO in unit of Metric tons/year, and the main sources include road dust, ships in the port area, general consumer goods, agricultural and construction machinery, etc.
2.Changes in emission trends: It shows that in addition to a slight decline in domestic energy consumption, the population, total number of motor vehicles, industrial production index, average GDP per capita, and the number of livestock pigs have all increased in 2019 in comparison with 2016. However, the results from TEDS 11.0 show that the total TSP, PM10, PM2.5, SOX, NOX and VOCs have all declined in comparison with TEDS 10.1. Among them, the most notable ones include point source TSP and SOX reduction of approximately 41% and 38%, respectively. The main reasons for the reduction include the improvement of factory control equipment, the elimination of fuel facilities, the elimination of old vehicles, the reduction in the sulfur content of merchant ships' fuel, and the reduction in the proportion of agricultural waste combustion. Obviously, the reduction of air pollutants is not caused by industrial production reduction or economic activity decline, but is the result of the national air pollution control.
3.Internal quality control, review and comparative analysis: According to the common problems from previous experiences, the inventory building has strengthened the automatic data link ＆ update function, automatic check function, emission continuity comparison, contact with county and city specialists, and history record of revision. Based on the uncertainty of emission parameters, we further explored the impact of individual pollution source factors on emissions. Sensitivity analysis results show that road dust, ships, general consumer goods, industrial surface coating, agricultural machinery gasoline burning, night market oil fume, etc. are the main pollution sources that affect the uncertainty of emissions. On the other hand, the comparison between model simulation and observational data shows that the TEDS 11.0 emissions have a certain degree of credibility.
4.Emissions management plan: Through the emission management plan, counties and cities are responsible for investigating and reporting certain data related to certain pollutant source emission estimates, such as cooking fumes at restaurants and night markets, burning of gold paper for folk beliefs, burning of agricultural waste, road dust, designated activity intensity of point source, etc. The works in 2021~2023 were scheduled, and the county and city reporting operations in the 2020~2021 period were implemented. The related explanatory meetings and education and training meetings on inventory emission estimation were held, in order to assist the local environmental protection bureau to complete the relevant work projects.
5.Standardized online reporting ＆ calculation integration system; other administrative coordination tasks: An integrated system platform has been developed, where the functions include area source emission calculation modules, historical reported data query, emission management plan reporting function, announcement message query function, basic account secret data maintenance, emissions trial calculation (partially open) etc. It also organizes explanatory meetings to understand user needs and improvement opinions. This system is scheduled to be officially launched in 111 years. Other administrative coordination tasks include the submission of the Green GNP air pollution emissions account form, the collection of the latest news on the establishment of emission data in European and American countries, the update and maintenance of the air pollution emission webpage data, and the assistance in handling seminars on aerosol related topics, etc.
