Degasning

Degasning (degassing) is the removal of dissolved gases from liquids or vapors from solids. Dissolved gases such as oxygen, carbon dioxide, nitrogen or hydrogen can affect taste, stability, corrosion, or mechanical properties. The goal is to reduce or modify the gas content to improve process control, safety, or product quality. The approach depends on the gas, the liquid, and the desired final gas content.

Common methods include vacuum degassing, where the pressure above the liquid is reduced so gases exsolve and escape; thermal degassing, which heats the liquid to reduce gas solubility; sparging or sweep gas, where an inert or non-reactive gas is bubbled through the liquid to carry dissolved gases away; and membrane degassing, which uses selective permeable barriers to remove gases under pressure or vacuum.

Applications span several sectors. In the beverage industry, degassing helps control carbonation, aid taste testing, and stabilize products such as wine and beer. In water treatment and environmental engineering, degassing removes oxygen and carbon dioxide to reduce corrosion and control emissions. In metallurgy and metalworking, degassing of molten metals removes hydrogen, nitrogen, and other impurities to improve quality. In the oil, electronics, and semiconductor industries, degassing removes dissolved gases from insulating oils and process liquids to prevent voids, bubbles, or contamination.

Measurement and control rely on dissolved gas analysis and vacuum or pressure controls. Safety concerns include handling under vacuum and preventing explosive mixtures when hydrogen or other flammable gases are involved.