The NEA Process
In a Near-Critical Expansion Atomization (NEA) process, the carbon dioxide is used in this process for the atomization and the crystallization of the product. The product subjected to the process is maintained in the liquid phase in a feed tank at a controlled temperature and subsequently conveyed, at the desired pressure, to the “atomization tower” where there is contact with the carbon dioxide released to atmospheric pressure.
The result is the formation of microscopic droplets (atomization) immediately cooled to temperatures much lower than 0° C.
The lipid is crystallized in a stable form, and particulate matter obtained has a narrow size distribution in the range 8–100 microns. The process parameters (carbon dioxide pressure and temperature and product) are regulated in function of the desired particle size.
The possibility of working small quantities of a product, even with a very low melting point, is an indisputable advantage compared to conventional processes. The direct contact between the product and the carbon dioxide also ensures the optimal exploitation of the properties of cryogenic gas.
The product obtained can be immediately inserted into the stages of production, mixed or packaged in a modified atmosphere using the carbon dioxide derived from the process.
With NEA process special applications are possible, for example in the pharmaceutical field, where fine particulates are required (5–30 micron) for the insertion of active ingredients in a matrix.