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1. The main sources from which carbon dioxide gas can be economically recovered include, as sources suitable for producing liquid carbon dioxide products: ① Hydrogen production off-gases from coal and natural gas: including decarbonization off-gases from ammonia synthesis and methanol production plants, hydrogen production decarbonization off-gases from refineries, and decarbonization off-gases from hydrogen peroxide production plants, etc； ②Fermentation off-gases: including alcohol fermentation off-gases, biogas decarbonization off-gases, etc ； ③Gases generated as by-products in chemical and petrochemical production: including natural gas purification and decarbonization exhaust gases, ethylene oxide decarbonization exhaust gases, melamine exhaust gases, lime kiln exhaust gases, and exhaust gases from oxygen-enriched combustion in furnaces. 2. In the liquid carbon dioxide production process, the carbon dioxide feed gas recovered through production processes and purification technologies is first buffered and separated. After being pressurized by a carbon dioxide compressor to facilitate the adsorption of harmful components, it exchanges heat with the cold energy provided by the refrigeration system, thereby turning into liquid carbon dioxide. A simple schematic is as follows: A reasonable process plan is designed based on the components of the carbon dioxide feed gas, the presence of harmful gases, and the requirements regarding the quality grade of the resulting liquid CO2 product. The typical production process design for liquid carbon dioxide currently involves adsorption + distillation, as well as catalytic oxidation to remove harmful components; a simplified schematic is shown below. 3. Main uses and specifications of liquid carbon dioxide: China’s current standards for liquid carbon dioxide are mainly divided into food-grade standards and industrial-grade standards. The standard for food-grade use is GB10621-2006 \"Liquid carbon dioxide as a food additive\" ； The main standards applicable to industrial-grade products are GB/T6052-2011 \"Industrial Liquid Carbon Dioxide\" and HG/T2537-93 \"Carbon Dioxide for Welding\". 3.1 Main uses of food-grade liquid carbon dioxide: (1) carbonated beverages (Pepsi/Coca-Cola, etc.), beer, and ready-to-make beverages (coke machines in fast-food restaurants, etc.) ； (2) Food preservation, food-grade dry ice, greenhouse vegetables ； (3) Puffed foods, tobacco shreds puffing ； (4) Supercritical extraction, etc ； 3.2 Main uses of industrial-grade liquid carbon dioxide: (1) Carbon dioxide shielded welding ； (2) Dry ice cleaning ； (3) Oil extraction ； (4) Rare earth mining and processing (strontium carbonate, barium carbonate, etc.) ； (5) Pharmaceutical and pesticide intermediates (monocyanamide, dicyanamide, etc.), chemicals, etc. 3.3 Carbon dioxide solidified into dry ice can be used for artificial rainfall, firefighting, mold casting, and more. 4. The product quality, CO2 recovery rate, and utility consumption of the carbon dioxide production units designed by our company: 4.1 All performance indicators of the products meet the **food-grade standards GB10621-2006 as well as the **industrial-grade standards GB/T6052-2011. 4.2 Carbon dioxide recovery rate: ≥75% 4.3 Utility consumption