Oxyfuel

Oxyfuel refers to processes that burn fuel gas in oxygen rather than in air, yielding a hotter, more controllable flame and an atmosphere that can be tailored for specific metalworking or combustion outcomes. The term covers both metalworking applications, such as welding and cutting, and industrial combustion schemes designed to facilitate carbon capture by producing CO2-rich exhaust.

In oxy-fuel welding and cutting, a burner blends a fuel gas (acetylene, propane, or natural gas) with a high-purity oxygen stream. In welding, the flame type is chosen to achieve neutral, oxidizing, or reducing conditions for proper metal fusion. In cutting, the preheated metal is oxidized by a jet of oxygen that blows away the molten oxide, enabling clean cuts in ferrous metals. Benefits include higher flame temperature, precise control, portability, and compatibility with a range of metals. Drawbacks include higher oxygen consumption, safety hazards associated with flammable gases and oxygen, and limited suitability for non-ferrous metals, which may oxidize or behave differently under the flame.

Beyond welding and cutting, oxy-fuel combustion is used in some power generation and industrial furnace contexts to burn fuel in nearly pure oxygen instead of air. The resulting flue gas is predominantly CO2 and water, which can simplify carbon capture and storage. Implementing this approach requires an air separation unit to supply oxygen, introduces energy penalties, and influences furnace design, heat transfer, and material requirements.

Equipment and safety considerations are central to oxyfuel systems, including oxygen supply, fuel gas handling, burners, and proper insulation. Safe operation hinges on managing the high flame temperatures and the oxidizer-rich environment to prevent unintended ignition and chemical hazards.