## 5 Discussion: Refrigerant Recycling and Carbon Offset  
The process of refrigerant treatment includes three parts: recovery, purification and regeneration. Refrigerant recovery refers to the process of extracting the refrigerant from the original equipment. Refrigerant purification refers to the process of removing impurities in the refrigerant one by one. Refrigerant regeneration refers to the process of recycling the refrigerant after recycling. The energy consumption of refrigerant recycling treatment equipment is mainly the power consumed by the heater and the power consumed by the compressor, and the main type of energy consumed is electric energy. Because there is no mature refrigerant recovery, purification and regeneration system available for experimentation, this article chooses the Beomseek refrigerant recovery machine (model BSE-1500A, an on-site refrigerant recovery machine) as a reference [19]. The power marked on the nameplate is used as the energy consumption data for the refrigerant recovery and regener  
Figure 5: Percentage of various types of energy carbon emissions. \begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Type of Energy**} & \multicolumn{2}{c}{**Energy Input**} & \multicolumn{2}{c}{**Emission Factor Information [18]**} & \multirow{2}{*}{**Carbon Emissions**} \\ \cline{2-2} \cline{4-5}  & **Quantity** & **Unit** & **Emission Factor** & **Unit** & **(kg)** \\ \hline natural gas & 49.03 & GJ & 0.056 & kg CO\({}_{2}\) eq/MJ & 2745.99 \\ electricity & 6875.09 & kWh & 1.35 & kg CO\({}_{2}\) eq/kWh & 9281.38 \\ coal & 0.15 & ton & 2.46 & kg CO\({}_{2}\) eq/kg & 369.29 \\ gas & 0.33 & ton & 2.663 & kg CO\({}_{2}\) eq/kg & 888.37 \\ fuel oil & 0.019 & ton & 3.12 & kg CO\({}_{2}\) eq/kg & 58.85 \\ water gas & 27.05 & GJ & 0.0944 & kg CO\({}_{2}\) eq/MJ & 2553.82 \\ total & & & & 15,897.73 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Energy consumption and carbon emissions per ton of R134a production process. ation process. Reference source. The equipment weight of the recovery machine is 2420 kg, the recovery compressor power is 5.5125 kw, the condensing unit power is 5.5125 kw, and the basic power of the machine is 2.205 kw. When the machine starts the recovery mode, the recovery rate is 2100 kg/h (liquid refrigerant) and 164 kg/h (gas refrigerant), when the machine starts the regeneration mode, the regeneration rate is 90-100 kg/h. The calculation shows that it takes timeR = 10.5 h to regenerate 1 ton of refrigerant, and the total power consumption is 138.9 kWh. Calculate the emission factor with reference to the \"US Greenhouse Gas Emission Inventory\" issued by the US Environmental Protection Agency (EPA) [20], the emission factor of electric energy is 1.35 kg CO\({}_{2}\) eq/kWh, and the regeneration of 1 ton of refrigerant will cause 0.188 CO\({}_{2}\) emissions per ton equivalent. From the calculation results, it can be seen that the use of recycling equipment to regenerate the refrigerant can reduce CO\({}_{2}\) emissions by 98.9% compared with re-production of the same amount of new refrigerant, which greatly reduces energy consumption and carbon emissions. However, not all refrigerants produced in the year can be recycled and reused. Taking the refrigerant used in automobile air-conditioning systems as an example, referring to the relevant leakage data of the automobile air-conditioning system refrigerant R134a emission rating [21], it is estimated that the average value of the regular leakage of R134a is 11.5 g/y, 17 g/y for unconventional refrigerant leakage [22], the leakage caused by professional maintenance is about 35 g [23], and the leakage caused by user maintenance is about 52 g [23]. The amount of refrigerant leakage in the recycling process of each scrapped car is 100-450 g, and the remaining recyclable portion of the refrigerant in the actual air conditioner of each vehicle accounts for about 42.8% of the total refrigerant used in the life cycle of the refrigeration system. In 2019, the annual output of R134a refrigerant was 153,000 tons [24].