Total heat energy exchangers

Abstract

Rotary regenerative total heat energy exchanger having an asbestos-free heat exchange media formed by spirally winding flat and corrugated webs of aluminum foil and/or fully bleached, 45 lb. Kraft paper constituted by 84% fibres and 16% salts. The contained salts are 90% ammonium sulfide and 10% diammonium phosphate. Wheel thickness for efficient transfer of both sensible heat and latent heat with minimal air pressure drop across the wheel is a multiple of from 100 to 400, preferably 125 to 200, times the flute height of the corrugation web of the media. Although media may be substantially all-paper, preferred embodiments provide media having both a flat web and a corrugated web of aluminum foil, a pair of paper webs being disposed respectively on the opposite surfaces of either the flat foil web or the corrugated foil web. Contiguous webs need not be adhesively secured together although, in modified embodiments, strips of neoprene rubber or silicate adhesive may be disposed between webs, or driable neoprene can be sprayed on end faces of wheel. Annular metal bands may be disposed at intermediate radial locations to strengthen the media. A metal rim forms the outer periphery of the wheel, and angularly spaced apart spokes are set into the media and extend radially between the hub and the rim. End edges of the peripheral rim, media, intermediate annular bands, and spokes are flush with each other.