What Does liquefaction Mean
The liquefaction or liquefaction is the change of state that occurs when a substance goes from a gaseous state to a liquid . The process occurs due to the action of temperature and the increase in pressure , which allows reaching a high overpressure. This differentiates liquefaction from condensation , which occurs when a substance changes state from vapor to liquid, due to the decrease in temperature.
Gas liquefaction, which was discovered by the British physicist and chemist Michael Faraday in 1818 , is achieved when a gas is cooled to its condensation temperature, then removing the latent heat of vaporization.
This process managed to improve the efficiency and lower the costs of the production of liquid air, thanks to its importance in the production of oxygen , nitrogen and other gases. It should be noted that lighters and carafes , among other items used in everyday life, contain liquid gas that was obtained thanks to liquefaction.
Finally, it can be mentioned that liquefied natural gas (LNG) is natural gas that has been processed for transportation in liquid form. LNG is considered the best alternative to monetize reserves in remote locations, where it is not profitable to bring gas directly to market through a gas pipeline or by generating electricity.
In this way, natural gas is transported as a liquid at atmospheric pressure and at -161 ° C , where liquefaction decreases the volume of gas transported by about six hundred times.
It is important to clarify that there is a semantic difference between the terms liquefaction and liquefaction , which makes them incompatible as synonyms in certain cases, particularly when talking about soils. The first is defined as the transformation into a gas of a gaseous or solid substance; the second is more precise, since it deals with the conversion into liquid only of a gas, by compressing it using considerably low temperatures .
Having said this, we can go on to define soil liquefaction , a phenomenon that consists of applying a great force (which is also known as load ) to a soil to make it go to a liquid state, or else its consistency passes to be that of a heavy liquid. It is considered a class of landslide , that is, what occurs when a large land mass moves and rushes along a slope or slope.
The liquefaction of the soil is produced by the instability of the inclination of the land that is called slope , which is carried out so that they mutually support each other. This phenomenon is one of the most serious, given its destructive effects. It occurs more frequently in loose granulated soils, with at least moderate saturation, with little drainage ; some examples are gravels and sands with streaks of sediment that impede the passage of water.
Throughout the process of soil liquefaction, while the external force (which is commonly cyclical and has no drainage) is in full action, the volume of loose sands tends to decrease. This causes an increase in the water pressure found in the pores, and in this way the shear stress decreases and the effective one begins to decrease .
The highest percentage of soils that undergo liquefaction are those made up of deposits that have occurred throughout the post-glacial period, the so-called Flandrian or Holocene , that is, in the last ten thousand years. These deposits usually have sediments and sands whose particles have comparable sizes, and are found in layers that are at least one meter thick .