New chemical removing and air cooling technology for clean room recirculation air using chilled pure water showering method

We have developed a new chemical removing and air cooling technique for clean room recirculation air using a gas-liquid contact method that consists of a combination of chilled pure water showering and optimum packing material. We have tested a new treatment system using this technique in an actual photolithography clean room finding many kinds of chemical contaminants of water-solubility substances such as NH/sub 4//sup +/ and amine ions, and have found it to be a sufficiently practical wet-type filtration method having both functions of chemical cleanliness control and air cooling capacity control. In addition, this new system has a very simple structure, less power consumption and is maintenance free. Furthermore, the total cost including the initial and running cost of the new wet-type chemical filtration system for clean room recirculation air using our new technique can be reduced by about 30%, as compared with that of a conventional dry-type chemical filter removal system.