| 摘要 |
The invention relates to a method and apparatus for producing sterile air suitable for being administered to intensive-care patients in hospitals. The main purpose is to obtain such sterile air starting from atmospheric air, with a more complete degree of purity than available from conventional methods using atmospheric air, and to obtain this medical-grade air free of gaseous contaminants and germs, at a cost substantially lower than when such air is prepared by mixing pure nitrogen with pure oxygen. The invention comprises compressing atmospheric air through at least one dry-piston compressor, condensing water vapor out of the compressed air through expansion into a buffer tank, filtering out dust particles down to micron size in a prefilter, drying the air through an adsorption desiccator and eliminating gaseous contaminants through an adsorption-desorption device. A second dust filter is provided for trapping any dust released from the adsorption units. The air is then treated for the elimination of biological contaminants, such as viruses and bacteria, by flowing through a sequence of three biological filters of the coalescence type, and finally through a cold sterilizing unit. A feature of the invention is that the desiccator and the unit for the elimination of gaseous contaminants use an active product of the same nature, namely a combination of metal oxides with K, Na and Mg silicates, the amount of this product being larger in the second unit than in the desiccator. |
