Degázás

Degázás is a term used in various scientific and industrial contexts to describe the process of removing dissolved or entrapped gases from a liquid or solid. The specific methods and purposes of degásing vary widely depending on the material and the application.

In the field of materials science and engineering, degásing is often crucial for producing high-quality materials. For example, in metallurgy, molten metals often contain dissolved gases like hydrogen, nitrogen, and oxygen, which can lead to defects such as porosity and embrittlement in the final cast product. Degásing techniques for metals include vacuum treatment, where the molten metal is held under reduced pressure to allow dissolved gases to escape, or sparging, where an inert gas like argon is bubbled through the melt to carry away the dissolved gases.

In the processing of polymers, degásing is essential to remove trapped air or volatile byproducts that can form during polymerization or extrusion. This is often achieved using vacuum ovens or specialized extruders with vacuum venting. In vacuum casting, degásing of both the resin and the mold is performed to ensure a bubble-free final product, common in industries like aerospace and 3D printing.

The pharmaceutical and food industries also employ degásing. For instance, carbonated beverages undergo a degásing process to reduce their effervescence if needed. In pharmaceutical manufacturing, degásing of solutions can be necessary to prevent issues during filtration or to ensure the stability of drug formulations.

The underlying principle of most degásing methods involves reducing the partial pressure of the gas above or within the material, or increasing the solubility of the gas in the surrounding medium (e.g., by using a carrier gas). The efficiency of degásing depends on factors such as temperature, pressure, surface area, and the viscosity of the substance being treated.