A The original 10-ton boiler, oil furnaces, and 4-ton boiler in Huayu Factory merely adopted water-film separators and wet scrubbers to filter flue gas, which did not meet emissions standards. In August 2019, the Huayu Factory invested 800,000 CNY to integrate the treatment of flue gas from all three boilers and added a set of baghouses, along with desulphurization and denitrification equipment, which effectively reduced the emission of sulfur dioxide, nitrogen oxides, and particulate matter, resulting in considerable environmental benefits. The project was officially completed in January 2020. After the completion of these modifications, emissions of sulfur dioxide, nitrogen oxides, and various particulates have met all environmental standards. This will reduce annual emissions of sulfur dioxide by 1.89 tons and nitrogen oxides by 2.32 tons.