| abstract |
Method and apparatus for removing dissolving radon gas from water for the purpose of reducing the exposure of household occupants to elevated airborne radon levels. Radon removal is accomplished by a membrane - mediated air stripping process which is based on the passage of radon from water (28) flowing along one surface of the membrane to stripping air (27) flowing along the second surface of the membrane. Particularly useful are dense polymeric membranes comprised of silicone rubber and hydrophobic microporous membranes. The dense membranes may be self-supporting, but are preferably composite membranes consisting of a dense film on a porous support membrane. The system can employ a subsystem for storage and recirculation of treated water through a housing in which the radon-permeable membrane is supported. Optionally, a hybrid subsystem can be employed which includes a carbon adsorption subsystem for the treated water downstream of the housing. |