Establishment Of HFC-134a Gridded Emission Inventory In China,Prediction And Dual Environmental Effect Analysis

As one of the main alternatives chlorofluorocarbons(CFCs)and hydrochlorofluorocarbons(HCFCs)to ozone-depleting substances,global emissions and atmospheric concentrations of the HFC-134a(1,1,1,2tetrafluoroethane)have increased year by year in recent years.Due to its high global warming potential and degradation to form trifluoroacetic acid(TFA),the HFC134a emissions have attracted global attention.There are differences in the results of existing top-down and bottom-up studies,and existing studies only estimated the total HFC-134a emissions at the national or regional scale,making it difficult to analyze the spatial distribution characteristics and regional contribution of HFC134a emissions.In this study,a gridded inventory estimation method for HFC-134a was established,and the HFC-134a gridded emission inventory(1 degree × 1 degree)in China from 1995 to 2020 was constructed and optimized,and the source structure,spatial distribution mechanism were analyzed.Different scenarios were set to project the emission reduction potential of HFC-134a by 2060,and its impact on climate change and TFA production.Results show that:1.Referring to the methodology of the 2006 IPCC Guidelines for National Greenhouse Gas Inventories,combined with analytic hierarchy and univariate allocation methods,the gridded emission inventory estimation method for HFC134a in production,automotive air conditioning(MAC),industrial and commercial refrigeration and air conditioning(ICR),foam and other consumer sectors was established.The ICR,MAC,foam and other consumer sectors used analytic hierarchy and single-factor allocation to establish provincial emission inventory estimation methods,and the gridded emission inventory estimation methods used gross domestic product(GDP)as the allocation parameter.2.Using the established gridded inventory estimation method,the HFC-134a gridded emission inventory was constructed from 1995 to 2020,and the results showed that the historical cumulative HFC-134a emissions were 354 kt(294-412 kt).The MAC is the most important emitting sector,with historical cumulative emissions of 136 kt(39%).The results of country list were in good agreement with the existing research results.Provincial and gridded inventories showed that the HFC-134a emissions were spatially unevenly distributed,with emissions concentrated in eastern and coastal areas of China.Guangdong,Jiangsu and Shandong were the three provinces with the largest emissions,with the historical total cumulative emissions of 98 kt(28%).The grid with the largest emissions was in Jiangsu Province,and Guangdong Province and Shandong Province were also the provinces where the hotspot grid was mainly distributed.3.Four scenarios of BAU,KA,KA-95%and KA-AS were set to analyze the emission reduction potential,and the results showed that the cumulative HFC-134a emissions under the BAU scenario would be as high as 7118 kt.Compared to the BAU scenario,the cumulative emission reduction under the KA scenario is 3603 kt.Compared with the KA scenario,the accelerated phase-out routes of KA-95%and KA-AS set in this study will reduce cumulative emissions by 107 kt and 694 kt,respectively.Two accelerated phase-out routes still have banks of 132 kt and 91 kt and emissions of 26 kt and 15 kt by 2060.In order to achieve China’s goal of carbon neutrality by 2060,the future emission reduction path of HFC-134a should be carefully planned,and HFC-134a should be phased out earlier and faster.4.From the analysis of climate change and TFA production,the results show that under the BAU scenario,the temperature increase caused by emissions will reach 0.08℃,and the cumulative potential production of TFAis 1185 kt.If 2,3,3,3tetrafluoropropene(HFO-1234yf)and Refrigerant-513 A(R-513A)are selected to replace HFC-134a in the future,it will effectively reduce greenhouse gas emissions and their climate effects,but will lead to the potential production of more TFA.Under the KA,KA-95%and KA-AS scenarios,the temperature increase caused by emissions are 3.6×10-2℃,3.4×10-2℃ and 2.6×10-2℃,respectively,which are much lower than those under the BAU scenario.However,the cumulative potential TFA production will be as high as 3.1 times,3.2 times and 3.6 times under the BAU scenario,respectively.Given the stability of TFA in water bodies and its aquatic ecological impacts,its risks should be regularly assessed.