Liquefaction

Liquefaction is a term used in materials sciences to refer to any process which either generates a liquid from a solid or a gas, or generates a non-liquid phase which behaves in accordance with fluid dynamics. Liquefaction occurs both as part of natural processes, and in man-made processes used in science and commerce. For example, "[a] major commercial application of liquefaction is the liquefaction of air to allow separation of the constituents, such as oxygen, nitrogen, and the noble gases", while another application is the conversion of solid coal into a liquid form usable as a substitute for liquid fuels.

In geology, soil liquefaction refers to the process by which water-saturated, unconsolidated sediments are transformed into a substance that acts like a liquid, often in an earthquake. By undermining the foundations and base courses of infrastructure, liquefaction can cause serious damage.

In physics and chemistry, the phase transitions from solid and gas to liquid (melting and condensation, respectively) may be referred to as liquefaction. The melting point (sometimes called liquefaction point) is the temperature and pressure at which a solid becomes a liquid.

In commercial and industrial situations, the process of condensing a gas to liquid is sometimes referred to as liquefaction of gases.

Coal liquefaction is the production of liquid fuels from coal using a variety of industrial processes.

Liquefaction is also used in commercial and industrial settings to refer to mechanical dissolution of a solid by mixing, grinding or blending with a liquid.

...
Wikipedia