With the intensification of global climate change, CO ₂ recycling technology has become a core means of industrial carbon reduction and resource recycling. The CO ₂ recycling machine separates and purifies carbon dioxide from industrial waste gas through physical or chemical methods, not only reducing greenhouse gas emissions, but also providing key raw materials for chemical, food and other fields, forming a closed-loop economic model of "capture utilization".

1、 Technical principles and core processes

CO ₂ recycling machines typically use chemical absorption, low-temperature separation, or membrane separation technologies. Taking the fermentation industry as an example, its process involves multiple key links:

Pretreatment of fermentation waste gas: at the beginning and end of fermentation, the content of CO ₂ is low and the purity is poor. It is necessary to remove foam in the gas through a demister, and adjust the pressure to meet the requirements of the suction end of the compressor.

Gas scrubbing and purification: The exhaust gas enters the scrubbing tower, and water sprays down from the top of the tower, fully contacting with the CO ₂ gas flowing from the bottom, dissolving impurities such as alcohol and sulfides. For alcohol fermentation, alcohol can also be recovered through a light alcohol absorption tower filled with metal Britex, with a recovery rate of 70%.

Drying and compression: The purified CO ₂ is dried and compressed to a pressure of 0.883 MPa or higher through a double tower, and converted into liquid or dry ice according to demand. Liquid recovery requires cooling to -20 ℃, while dry ice recovery requires the formation of snowflake shaped dry ice at the triple point (0.528 MPa, -56 ℃).

Refining and storage: Organic impurities and unpleasant odors are further removed through adsorption towers to ensure a CO ₂ purity of 99% -99.5% or higher, and stored in storage tanks or steel cylinders.

2、 Application scenarios and industry value

Food and beverage industry: CO ₂ is an important byproduct in beer and alcohol production. Through recycling machines, the beer industry can recycle hundreds of thousands of tons annually, meeting the needs of processes such as carbonation and packaging, and reducing external procurement costs.

Industrial and Commercial Refrigeration: Haier's PROFROID brand has introduced CO ₂ technology into the HVAC field, launching transcritical air conditioning systems and heat pump units. Its CO ₂ refrigerant does not damage the ozone layer, with a GWP value of only 1. The energy efficiency ratio and reliability are significantly improved. For example, the "Ice Ribbon" at the National Speed Skating Oval adopts a transcritical CO ₂ heat recovery scheme, saving up to 2 million kWh of electricity annually.

In the field of chemical and energy, recovered CO ₂ can be used to synthesize chemicals such as urea and methanol, or injected into oil fields to enhance oil recovery. In addition, CO ₂ can also be used as a solvent for processes such as dry ice cleaning and supercritical extraction.

The CO ₂ recycling machine is not only a tool for addressing climate change, but also an important engine for promoting industrial green transformation. With technological advancements and policy support, it will play a greater role in the global carbon circular economy, helping to achieve the "dual carbon" goal.