Exhaust gas treatment method and apparatus
AssigneeHeat Exchanger Industries, Inc.
InventorDonald F. Warner
Life of this patent
Estimating the term…
Abstract
Exhaust gas treatment method and apparatus extract heat from an exhaust gas by operating in a water-condensing mode which allows more heat to be recovered, removes particulate matter and condensed acid from the exhaust gas, and washes heat exchange surfaces to keep them clean and wet to improve heat transfer. Systems for heating water, air and both water and air are disclosed. Methods of constructing and assembling improved heat exchangers are disclosed.
Claims44
Apparatus for recovering heat energy from an exhaust gas which contains water vapor and sulfur trioxide, comprising, in combination;
- means defining a gas-passage housing;
- a plurality of tubes extending generally horizontally through said gas passage housing at a plurality of different levels, the exterior surfaces of said tubes within said gas passage housing carrying corrosion-protection coverings;
- means for applying said exhaust gas to said gas passage housing for flow of said exhaust gas generally perpendicularly to and between said tubes and through said housing;
- means for passing a fluid to be heated which is initially cooler than the dew point of said water vapor through successive ones of said tubes, thereby causing continuous condensation of water vapor and sulfuric acid and a continuous washing of a group of lower tubes in said housing, said gas passage housing comprising a pair of spaced-apart tube sheets each having a plurality of holes, a plastic corrosion-portection material covering the inside of each tube sheet and extending through each of the holes in the tube sheet, said tubes extending through pairs of holes in said tube sheets, said plastic corrosion-protection material extending through said holes gripping the corrosion-protection material on the exterior surfaces of said tubes.
Apparatus for recovering heat energy contained in a hot exhaust gas which contains water vapor and a corrosive constituent, and for removing substantial amounts of said corrosive constituent from the exhaust gas, comprising, in combination:
- means defining a gas passage housing;
- a tube nest comprising a plurality of tubes spaced apart from each other and extending generally horizontally through said gas passage housing at a plurality of different levels, the insides of said gas passage housing and the exterior surfaces of said tubes within said housing being covered with corrosion-protection coverings;
- means for passing said exhaust gas in heat exchange relationship generally perpendicularly to and between said tubes and through said gas passage housing;
- and means for forcing a fluid which is initially cooler than the water vapor dew point of said exhaust gas through successive tubes of said nest at a flow rate such that the temperature of said fluid within a first group of said tubes remains below said water vapor dew point to cause continuous substantial condensation of water from said exhaust gas and a continuous fall of water droplets from tubes at at least one of said levels through said exhaust gas to tubes at a lower one of said levels, said corrosion-protection coverings on said tubes promoting dropwise condensation of said water droplets on said tubes.
Heat exchanger apparatus, comprising, in combination:
- a pair of side members and a pair of metal tube sheets defining a generally rectangular housing, each of said tube sheets having a plurality of holes;
- a pair of plastic sheets covering the inside surfaces of respective ones of said tube sheets with portions of said plastic sheets extending through each of said holes in said tube sheets to the outside of the tube sheets;
- and a plurality of metal tubes having plastic exterior coverings, each of said metal tubes extending through respective holes in both of said tube sheets and being mechanically fixed in place by the gripping of its exterior plastic covering by the portions of the plastic sheets which extend through the tube sheet holes through which the metal tube extends.
Dependencies are inferred from the claim text.