Liquid and Compressed Carbon Dioxide (CO2) We commonly know carbon dioxide (CO2) as a product of combustion, as an critical ingredient in photosynthesis, a plant’s ability to transform carbon dioxide and water to glucose and oxygen in the presence of light, and the stuff that provides “carbonation” to soft drinks, beer and sparkling wines.But where does purified carbon dioxide come from? With all the attention around climate change and the role that carbon dioxide in that process, you might think that atmospheric extraction would make the most sense. As it turns out, atmospheric levels of carbon dioxide average less than 450 parts per million, making that process not the best way to get the job done and cos too much money to provide any value. Similarly, natural fermentation works fine in a wine bottle and brewing tank, but that process doesn’t have much upscale potential. No, mostly all the purified carbon dioxide that available on the market today is a byproduct of chemical manufacturing, oil refining and natural gas purification.Carbon dioxide is a colorless, odorless, nonflammable slightly acidic gas and, because it is available on such a large scale, has many uses in a number of different industries. The food industry uses CO2 in food freezing, carbonated beverage manufacturing and modified atmosphere packaging. Carbon dioxide is known as an “active gas” in shielding the arc in gas metal arc welding (GMAW / MIG welding) either by itself or in mixtures of argon and helium. Its acidic properties mixed with water make it a good water treatment additive for pH control. Liquid Carbon Dioxide is also expanded in specialized equipment to produce “dry ice” blocks and nuggets used for temporary refrigeration.Higher purities of carbon dioxide, from Dry to Ultra High Purity and Research Grades are utilized in laser cutting and marking operations, spanning everything from medical devices to steel fabrication. Growers apply controlled amounts of CO2 to bring out the best in fertilizers in greenhouse operations. High purity CO2 is generally used as an oxygen-free atmosphere for anaerobic incubation, and in the preparation of special application mixtures for blood gas monitoring.With all these applications, having local Indianapolis experts on hand to answer questions about carbon dioxide can be really helpful. Give them a call today at American Welding & Gas, Inc. at or contact us online.