Abstract:
Unusually strong and highly perforated plates are formed by pressurized filtration of a suspension of chopped ceramic fibers in an aqueous dispersion of colloidal alumina or colloidal silica through a mold (10) having a perforated filter base (20) and a pin support base (12) having pins (14) that extend through and beyond the perforations (25) of the filter base (20). Pressurized filtration is preferably conducted by applying vacuum on the downstream side of the mold. When the resulting compact layer of chopped fibers (24) deposited on the perforated filter base (20) has the desired thickness, filtration is stopped. The perforated filter base (20) and pin support base (12) are moved apart to retract the pins (14) from contact with the perforated compact layer of chopped fibers (24) which is transferred to a drier. By operating the drier at a temperature not exceeding about 650 DEG F (343 DEG C), the compact layer of chopped fibers (24) is converted into a novel unsintered, perforated plate of unusual strength.
Abstract:
A water heater (10) of simplified construction which incorporated a unique infrared gas burner performs with notable thermal efficiency and suppression of the combustion pollutants, nitrogen oxides. The upright cylindrical water tank (11) of the new water heater is supported by a cylindrical metal skirt (15) having the same diameter of the tank. A circular perforated ceramic plate (16) is fitted transversely in the skirt (15) to provide a combustion zone (17) above it and a plenum (18) for fuel gas and air below it. A venturi tube (19) extends through the skirt (15) into the plenum (18) for the injection of gas and air. The flameless combustion occuring at the exil surface of the perforated plate (16) makes it a radiant emitter of infrared energy aimed at the bottom (13) of the water tank (11).
Abstract:
A gaseous fuel burner and method in which a high-firing rate (blue/non-surface) (9) zone is created between two lower firing rate (red/surface radiant) (3) combustion zones. The method of the invention can be achieved by selective perforation of porous sintered fiber mat burner surfaces to achieve improved burner performance and relatively low NOx emissions.
Abstract:
A gas-fired bayonet-type heater (10) has a tubular shell (11) containing a tubular porous fiber burner (17) having a high length-to-diameter ratio attached to a long feed tube (15) for the gas-air mixture. An annular space around the burner (17) and feed tube (15) within the shell (11) provides the path for the combustion gases to flow to a discharge opening (19) near the entry point of the gas-air mixture.