Carbon dioxide is an odorless (at very low concentrations), colorless gas that is stable at room temperature. Living creatures produce carbon dioxide as a waste product of respiration, which is then utilized by plants to form food by photosynthesis. Carbon dioxide also has numerous industrial and commercial uses—ranging from firefighting to electronic equipment manufacture.
Carbon dioxide gas is used in industries to produce chemicals and as feedstock. According to “IPCC Special Report on Carbon Dioxide Capture and Storage,” carbon dioxide gas is involved in the production of refrigeration systems, welding systems, water treatment processes (to stabilize the pH of water) and carbonated beverages. It is also used in the metals industry to enhance the hardness of casting molds and as a soldering agent. Carbon dioxide is found in various fire extinguishers and prevents oxygen from further fueling a fire. Carbon dioxide-based fire extinguishers effectively manage electrical fires and those caused by solvents, fuels and oils.
Chemical and Pharmaceutical Applications
Carbon dioxide gas is used to make urea (used as a fertilizer and in automobile systems and medicine), methanol, inorganic and organic carbonates, polyurethanes and sodium salicylate. Carbon dioxide is combined with epoxides to create plastics and polymers. It is used for water treatment; to keep food cool (as dry ice); and to cool, pressurize and purge equipment.
Carbon dioxide gas is used in the electronics industry for circuit board assembly, to clean surfaces and in the manufacture of semiconductor devices.
Carbon dioxide gas is used in enhanced oil recovery (EOR). EOR is a class of techniques for increasing the quantity of extracted crude oil from oil fields. Carbon dioxide is injected under high pressure into an oil reservoir, which pushes the oil through pipes and up to the surface of the ground. Carbon dioxide gas injection aids oil recovery and reduces the viscosity of recovered oil.
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