Abstract: A method of operating an industrial furnace, the steps that include providing a process heating zone containing heat exchange tubing for flowing process fluid through the zone; providing first and second fuel combustion zones, and first and second heat regeneration zones; during a first time interval flowing a first stream of air through the first regeneration zone to be preheated therein, flowing the preheated air stream to the first combustion zone to support combustion of fuel therein producing a flame and hot combustion gases, transferring heat from the flame and the hot gases to the heat exchange tubing in the process heating zone, and then flowing the hot gases to the second heat regeneration zone for extracting heat from the gases at the second regeneration zone; and during a second time interval flowing a second stream of air through the second regeneration zone to be preheated therein, flowing the second preheated air stream to the second combustion zone to support combustion of fuel therein producin

Abstract: A ceramic gas burner for a hot-blast stove has a burner crown essentially composed of a plurality of shaped bricks which define terminal portions of at least one combustion air duct and at least one gas duct of said burner for flow of respectively combustion air and gas. A simple and inexpensive structure is obtained when the bricks are of at most two principal types in respective layers. The bricks of each type are identical, but may be of a subsidiary type of which two bricks combine to form one brick of the principal type.

Abstract: A scrap metal recycling furnace system comprises a dry hearth furnace, a closed well furnace, an afterburner chamber, a regenerator, a safety cooler and a fume purification plant operably interconnected by a plurality of conduits to form a system wherein exhaust gases from each component of the system can be selectively supplied to at least one other component of the system.

Abstract: A regenerative burner includes a chamber containing heat storage bodies which extract heat from hot products of combustion flowing through the burner during one part of a cycle of operation and yield up that heat to incoming air during a further part of the cycle.

Abstract: A linear combustion emitter regenerator process capable of operating at high temperatures for sustained periods of time, that includes flowing reactants including fuel and air to a combustion zone; adding regenerated heat to at least one of the reactants flowing to the zone; combusting the reactants at the zone to produce combustion products at high temperature, to heat radiant emitter; operating the emitter to radiate energy from the zone passing selective wavelengths of said radiated energy spectrum through an optical filter and converting the radiation from the emitter into photovoltaic-produced electricity; mounting optical filter on water-cooled window to act as a heat shield to protect photovoltaic cells from overheating; reflecting back to the emitter portions of the spectral emission not able to activate the photovoltaic cells; extracting heat absorbed by liquid-cooled window by means of a heat exchanger to transfer heat to incoming combustion air; extracting heat from the combustion products for retu

Abstract: An air heating apparatus for air that is to be supplied to a blast furnace. The apparatus includes a number of separate air heater devices connected together in series flow relation so that the total temperature increase is the sum of the heating actions produced in the individual devices. Each device includes a tube-shell heat exchanger and a plurality of burner units oriented around the shell to direct flames against outer surfaces of the tubes.

Abstract: The present invention is a regenerative gas incineration apparatus having three heat regenerators containing refractory heat exchange material. Gas is cycled through the regenerators first in one direction, then in another. The regenerators are each connected to combustion chamber having an air-fuel system and at least one burner. A system of valved ductwork is utilized to direct gas to be processed into and upwardly through a heating first regenerator into the combustion chamber, downwardly through a cooling second regenerator and exhausting the processed gas to the atmosphere. The temporarily idle third regenerator is purged of partially treated gas remaining from a previous cycle and this gas is directed to the combustion chamber. The flow of the gas through the system is periodically changed enable the heat recovered by cooling regenerator in the previous cycle to be used to heat incoming gas in the next.

Abstract: In a method for the thermal treatment of wastes (combustible, poorly combustible and incombustible), especially those which cannot be harmlessly dumped, air is preheated in a first regenerator (2) to a temperature of 800.degree. to 1200.degree. C. and fed through a first combustion chamber (7) to a melting vessel (6) into which wastes are dumped for thermal treatment. The flue gas from the melting vessel is fed through a second combustion chamber (7') to a second regenerator (2'). The two regenerators contain sections for thermal storage (3, 3'), for the adsorption (4, 4') of flue gas impurities and for the further treatment (5, 5') of the flue gas. The air and flue gas flow is reversible, i.e., air preheated in the second regenerator (2') is fed to the melting vessel (6) through the second combustion chamber (7'). The flue gas is fed through the first combustion chamber (7) to the first regenerator (2).

Abstract: A method for removing magnesium and calcium from sodium sulfate solutions to render the solutions suitable for membrane processing, which comprises adjusting the pH of the solutions to about 11 to 13 with sodium hydroxide to form a precipitate containing the bulk of the magnesium and the calcium, removing the precipitate from the resulting partially purified sodium sulfate solution, and contacting the partially purified sodium sulfate solution with a polystyrene divinyl benzene copolymer chelating cation exchange resin having an aminophosphonic functional group and having sodium as the exchangeable cation, to remove essentially all of the magnesium and the calcium from the partially purified sodium sulfate solution.

Abstract: The presence of the oxides of nitrogen in the exhaust gas leaving a regenerator is limited by injecting water or water vapor into the regenerator 1 during its firing phase and causing the water or water vapor to reach the combustion chamber 26 of the regenerator 1 by way its heat storage bed 11 which has been preheated during a previous heat collecting phase.

Abstract: A regenerative bed is operated in a separate, additional cleaning cycle by heating the regenerative bed media to a temperature above the condensation temperature of contaminants in order to liquify and drain of the same off of the bed media. In the preferred embodiment shown, this is accomplished by over riding the normal cycling of the regenerative beds so as to retain a subject bed in a fluing mode for an abnormal amount of time (trading bed efficiency for the heating of the bed). The beds preferably also incorporate an escape opening 13 to drain off the contaminants.

Abstract: A regenerative burner system comprises two burners alternately fired and each having an air and fuel supply thereto traversing separate heat exchangers. The arrangement is such that the hot gases exhausted from the furnace during firing of the one and the other burners traverse the heat exchangers associated with the other and the one burners, respectively, relinquishing heat thereto whereby both the fuel and the air supply to each burner extracts heat from its associated heat exchanger during the firing cycle of that burner. By heating both the fuel and the air input to the regenerative system, fuels of low calorific value, e.g. blast furnace gas or any gases low in or devoid of hydrocarbons may be efficiently utilized to provide a stable high temperature flame without the need for enrichment with `pilot` fuels.

Abstract: An improved immersion tube heater means is disclosed for uniformly and reliably heating oils to a temperature below the oil's critical physical breakdown temperature so as to avoid damage to the oil and coating the tube with damaged oil byproducts.

Abstract: A method of combusting fuel in a furnace having a pair of regenerative burners, each burner having a combustion chamber and a regenerative bed having an exhaust means incorporated therewith introducing simultaneously into said combustion chamber of each burner approximately identical amounts of fuel and approximately identical amounts of oxidizing gases from at least two sources of oxidizing gases having different oxygen concentration to produce two approximately identical flame patterns directed toward the interior of said furnace; terminating the supply of fuel and said oxidizing gases to one of said burners to create a non-firing burner having a non-firing period while maintaining the production of a flame in the remaining burner to create a firing burner having a firing period; applying negative pressure to the exhaust end of the regenerative bed of said non-firing burner to initiate the exhausting of flue gases produced by said firing burner; alternating the introduction of fuel and at least one oxidizin

Abstract: A process and apparatus for oxygen-rich combustion wherein a first portion of about 5 to about 40 percent of the total fuel to be cracked and combusted is introduced to a cracking chamber where it is combusted and cracked at a temperature below about 2200.degree. F. to produce a cracked products mixture. Oxygen-rich gas of greater than about 30 volume percent oxygen is introduced to the cracking chamber in about 5 to about 50 percent of the stoichiometric requirement for complete combustion of the first portion of fuel introduced to that chamber. Cracked products mixture, a second remaining portion of fresh fuel and oxidizer having sufficient oxygen for substantially complete combustion of the combustible portion of the cracked porducts mixture and the fresh fuel are introduced to a combustion chamber wherein the combustible portion of the cracked products mixture and the fresh fuel are combusted.

Abstract: A pair of regenerative burners is provided with feed means (25) for feeding a reducing agent into the products of combustion so that this agent can reduce oxides of nitrogen in the heat store to which heat is imparted by the products of combustion. Refractory elements (17,21) comprised by the heat stores may additionally or alternatively have catalytically active surfaces to promote reaction of the lower oxides of nitrogen.

Abstract: A ceramic gas burner for a combustion chamber of a hot-blast stove of a blast furnace has parallel vertical supply ducts for the two combustion components (gas and air). One duct opens upwardly at a first outlet opening which is rectangular in shape. The second duct opens at second outlet openings which are on each side of and above the first outlet opening and whose outflow directions are oblique to that of the first outlet opening. Recesses extend in each long side of the first opening towards the second openings. To improve the mixing of the two components, opposite each recess there is another such recess in the other long side of the opening.

Abstract: A method and apparatus for improving the performance of a regenerative burner has a combustion chamber which receives and combusts controllable amounts of auxiliary fuel, an oxidizing gas, and possibly air to form hot combustion products. A controllable amount of a main fuel is then delivered to the combustion chamber and is pyrolyzed by the hot combustion products to produce a hot flame. By controlling the flame, one can maintain optimal temperature of the combustion air passing through the flame. Sensing means and computing means allow for automatic adjustments of fuel, oxygen and air flow to further maintain optimal combustion air temperatures.

Abstract: The present invention relates to a low NOx radiant tube burner. The radiant tube burner consists of; a primary combustion chamber which is located outside of the furnace and having an injection outlet of the combustion gas located approximately more inside of the furnace than the bung of the radiant tube, a primary fuel nozzle which injects primary fuel into the primary combustion chamber, and a secondary fuel nozzle which is surrounded with refractory material and injects secondary fuel into the radiant tube from the area adjacent to the injection outlet. Approximately the total amount of the combustion air is supplied into the primary combustion chamber with primary fuel under a high excess air ratio creating primary combustion. The low concentration of oxygen remaining in the primary combustion gas combined with the secondary fuel creates secondary combustion.

Abstract: A ceramic burner for a hot blast stove, having a burner head where the combustion components mix and an air duct and a gas duct beneath the head for conducting combustion components to the head, the gas duct is within the air duct and is bounded by a wall. To prevent stresses due to differences of thermal expansion at least one horizontal sliding joint is arranged in the bounding wall of the gas duct closely under the burner head. The air duct is bounded by a brickwork wall which continues upwardly past the burner head and forms a combustion chamber. The burner head projects over and is supported by a shoulder in this wall and an essentially vertical expansion joint is located between the burner head and the wall.

Abstract: A high efficiency, high temperature radiant heating system utilizing regeneratively coupled combustors. The combustor/regenerator units each comprise a porous body with combustion supported in one layered zone and regeneration occurring in an adjacent layered zone in a subsequent cycle. Each combustor/regenerator unit cycles between combustion and regeneration operational modes and is gas flow coupled with a similar unit operating simultaneously in a mode opposite that of the former. Heat in the combustion products produced at one combustor/regenerator unit is received at the regenerator zone of the other coupled unit and vice versa.

Abstract: A regenerative burner includes a chamber containing heat storage bodies which extract heat from hot products of combustion flowing through the burner during one part of a cycle of operation and yield up that heat to incoming air during a further part of the cycle.

Abstract: An auxiliary flue is disclosed to vent contaminants from a regenerative burner furnace during secondary operations so as to avoid damage to the burners from such contaminants.

Abstract: A regenerator for a regenerative heating system comprises a chamber 2 for storing a heat storage bed in the form of discrete particles 45, a closable inlet 16 for introducing fresh particles into the chamber 2 to replace contaminated particles and a closable outlet 18 for removing the contaminated particles from the chamber 2 so that the fresh particles may be introduced.

Abstract: The presence of the oxides of nitrogen in the exhaust gas leaving a regenerator is limited by injecting water or water vapor into the regenerator 1 during its firing phase and causing the water or water vapor to reach the combustion chamber 26 of the regenerator 1 by way its heat storage bed 11 which has been preheated during a previous heat collecting phase.

Abstract: The regenerative heating apparatus (FIG. 1) comprises a pair of regenerators 51a and 51b arranged so that in use while one is being heated by waste gas, the other is preheating air for the combustion of fuel. A reversing valve 58 is connected to each lower end 91a and 91b of the regenerators 51a and 51b, the valve 58 connecting the regenerators 51a and 51b to an inlet 99 for receiving air and an outlet 100 for discharge of the waste gas. The reversing valve 58 is reversible to connect one regenerator to the inlet and the other regenerator to the outlet. Each regenerator incorporates at its upper end a burner (B1 and B2) with as shown in FIG. 2 a body having a passage 2 formed with openings 3 and 4. The opening 4 serves to receive air for combustion when its regenerator is preheating air or to discharge waste gas to the regenerator while the opening 3 serves to supply combusted fuel and air to the furnace 90 or to receive waste gas from the furnace 90.

Abstract: A regenerative heating system includes at least a pair of regenerators of the type which are operable so that while one is being heated by waste gas the other is heating air for the combustion of fuel. The system includes a pair of regenerators 1 and 2 which are interconnected adjacent one end to form a chamber 4 having an outlet 8 to discharge waste gas flow into the chamber from one or other of the regenerators. Air nozzles 7 extend into the chamber 4 to inject air into the regenerators 1 and 2 during the air heating cycle of regenerator. The waste gas may be removed by the suction force of a fan or eductor.

Abstract: A system for preheating air being fed to a continuous fired furnace by means of high temperature waste gases exhausted from the furnace. The system includes two pairs of interconnected regenerators. The regenerators of one pair are alternately connected by means of a reversing valve to an ambient air inlet and a waste gas exhaust stack, and the regenerators of the other pair are alternately connected by means of a second reversing valve to the furnace's waste gas outlet duct and combustion air inlet duct.

Abstract: A burner for use in a heat regeneration system for a combustion furnace. The burner includes a burner shell having two internal chambers, wherein the first chamber is disposed on the flame axis of the burner, and the second chamber surrounds the radial perimeter of the first chamber. A gas permeable, annular regenerative bed separates the first and second chambers such that gas flow between the first and second chambers must travel through the regenerative bed in a direction which is generally radial with respect to the flame axis. The burner has "flue" and "fire" modes of operation. Valving elements are included for supplying combustion air to the second chamber under pressure when the burner is in the fire mode, and for exhausting products of combustion (POC) from the second chamber when the burner is in the flue mode. In the disclosed embodiment, the burner valving elements are annular and integral with the burner body.

Abstract: An apparatus for monitoring a negative pressure atmosphere, e.g. a regenerative furnace atmosphere during an exhaust cycle, has aspirating facilities for aspirating an atmospheric sample from the negative pressure atmosphere and moving the sample past an analyzer for content analysis thereof.

Abstract: A burner tip for passing fuel into a glass melting chamber, the burner tip having at least a portion thereof extending a distance into a fuel input passageway fluidly communicating the chamber interior to the chamber exterior, the distance being sufficient to minimize inspiration of chamber exterior or ambient air through an unsealed space formed between the outside surface of the burner tip and the walls forming the fuel input passageway, into the chamber interior, wherein at least the portion of the burner tip which extends into the fuel input passageway is made of high temperature, high oxidation-resistant material capable of withstanding the chamber interior atmosphere during both firing and off-firing cycles, while in direct contact therewith over a substantial time period.

Abstract: Pneumatic control of flow patterns in regenerators is improved by the use of flow amplifier nozzles.

Abstract: There is disclosed an apparatus and method of recovering a portion of the waste heat produced in a high temperature industrial process, such as a glass melting furnace, where the furnace has at least a pair of regenerators which are alternately used to preheat the combustion air and serve as hot exhaust heat storage means. The hot exhaust gases from the process are passed through a heat exchanger where the heat is indirectly transferred to the clean compressed air at 100 psi from the compressor of a Brayton cycle energy recovery system with the hot compressed air being expanded in a high performance turbine. The exhaust from the turbine will be at atmospheric pressure and at a temperature between 750.degree. F. and 900.degree. F. This turbine exhaust is fed to the opposite side regenerator as clean preheated combustion air.

Abstract: A heat regenerator for use in heating an enclosure such as a furnace.The heat regenerator 51 is detachable at one end from a burner B and at its other end from a reversing valve 58. The regenerator 51 comprises two axially engaging portions 56 and 57, the front portion 56 comprising a cylindrical heat storage bed 59 and a surrounding annular layer 60 of a ceramic fibre insulation material. The rear portion 57 comprises a cylindrical body of refractory having a bore 61 forming a bottle-neck type passage tapering towards the valve 58. The heat storage bed 59 comprises a monolithic refractory block through which a multiplicity of axially aligned gas-carrying channels 65 extends. These channels 65 convey combustion products from the burner portion 52 to the regenerator portion 56 in one mode of operation where the bed is extracting heat from the products for storage.

Abstract: In a regenerative furnace of the type used for melting glass, localized overheating of the regenerator packing is minimized, heating of the regenerator packing is made more uniform, and regenerator efficiency is improved by employing flow control gas jets in the space alongside the regenerator packing to counteract flow imbalances in the regenerator.

Abstract: In a multiport combustion furnace having a plurality of firing ports in undivided communication with a common source of combustion gas or air, the invention provides a method and apparatus for selective control of combustion air flow into one or more of the ports. A small quantity of pressurized gas, e.g. air, is injected, e.g. by way of a flow control pipe in an individual port, generally along the flow path of combustion air through the port to alter the amount of combustion air flowing into the port for mixing with fuel. Combustion air is increased by injecting air cocurrent with the combustion air flow to induce additional flow into the port. Combustion air is decreased by injecting air countercurrent to the flow to impede flow through the port.

Abstract: A method of and apparatus for selective control of combustion gas flow in a furnace firing port in a furnace of the type having a plurality of firing ports, each port having a passageway for receiving combustion gas, e.g. preheated air, from a common plenum chamber, wherein the chamber includes a back or target wall in opposed spaced relationship to each of the passageways. A flow control pipe is inserted through a plenum wall directed toward the passageway between the plenum and port. A small quantity of pressurized gas, e.g. air, is injected generally along the flow path of combustion air in the plenum toward passageway to alter the amount of combustion air flowing into the port. In a preferred embodiment, combustion air is increased by injecting air through a target wall flow control pipe cocurrent with the flow to induce additional flow into the port and combustion air is decreased by injecting air countercurrent to the flow adjacent to the passageway to impede flow into the port.

Abstract: A continuous regenerative tank-type glass melting furnace having a plurality of burner ports along each side in communication with a longitudinally extending plenum. Beneath and extending throughout the length of each plenum is a checkerbrick structure supported upon longitudinally extending arches carried by transverse walls. The walls divide the area beneath the checkerbricks into a plurality of chambers, each chamber being below a corresponding one of the ports. A tunnel joins each chamber to a common manifold connected to a reversing combustion air and exhaust gas system. Each tunnel is provided with a damper for varying its effective cross-sectional area, thereby permitting improved regulation of the flow distribution of exhaust gases and combustion air through the regenerators.

Abstract: A heating flue for a coke oven includes a wedge-shaped refractory brick having at least one oblique surface and vertical cylindrical bores when the brick is inserted into the vertical portion of a duct at the bottom of the heating flue. This part of the duct has an increased diameter to support the brick so that the vertical sides abut the inner duct walls and the bottom oblique surface extends toward the mouth of an obliquely-rising portion of the duct. The sum of the cross-sectional areas of the cylindrical bores in the brick is from 0.75 to 1.5 times the flow cross section of the obliquely-rising duct portion. The cross-sectional area of the top of a wedge-shaped brick which is coplanar with the flue base is in a range of between 20 and 200 with the cross section of the cylindrical bore in the brick. The diameter of the bore is between 10 and 60 millimeters. A ratio of 0.3 to 1.

Abstract: Disclosed are checker tiles for regenerative heating stoves, each tile having the general shape of a parallelepiped, the preferred tile being square in plan, having apertures extending through the tiles and having complementary ribs and grooves extending on the ends of the tile between adjacent apertures to interlock the tiles with contiguous end-abutting tiles and prevent substantial lateral movement thereof when the tiles are arranged in stacked overlapping relation.Also disclosed is supporting means for checker tiles providing for low friction and preferential sliding of horizontal contacting surfaces to permit lateral relative movement between the lowermost course of tiles and supporting means that avoids damage to tiles on dimensional changes of the tiles or supporting means due to temperature changes in operation of the stove.

Abstract: In a regenerative furnace of the type used for melting glass, localized overheating of the regenerator packing is minimized, heating of the regenerator packing is made more uniform, and regenerator efficiency is improved by employing air jets in the space alongside the regenerator packing opposite the flue to counteract flow imbalances in the regenerator.

Abstract: In a regenerative furnace of the type used for melting glass, localized overheating of the regenerator packing is minimized, heating of the regenerator packing is made more uniform, and regenerator efficiency is improved by employing a gas stream, preferably a high velocity burner, in the plenum of the regenerator to control gas flow distribution within the regenerator.

Abstract: NO.sub.x emissions from a glass melting furnace are reduced by injecting ammonia into the exhaust gas stream on a flue between primary and secondary regenerator chambers in one embodiment, and in staged zones within a regenerator in another embodiment.

Abstract: A method of and apparatus for directing and regulating the flow of combustion air to opposite ends of the regenerators of a regenerative tank-type glass melting furnace so as to minimize localized overheating and more uniformly heat the checkerworks of the regenerators, thereby improving the operating efficiency and prolonging the useful life thereof. To accomplish these ends, a substantial portion of the combustion air supplied to the regenerators is delivered to their downstream ends while a lesser portion is supplied to their upstream ends by ducts which include valves for cycling and a damper for apportioning the amount of combustion air flowing to opposite ends of the regenerators.

Abstract: A coking oven having a coking chamber and a combustion chamber with a high temperature flue gas outlet connected to a first heat exchanger for heating cool air to cool the flue gases to an intermediate temperature, a coal dryer using the intermediate temperature flue gases for drying wet coal to a water content of a few percent by weight and preheating the coal to a temperature below the boiling point of water, a coal oiler to oil the partially dried and preheated coal, and a gas cleaner system for removing particulate matter from the low temperature flue gas coming from the coal dryer; also disclosed is an improved method of coking coal and apparatus for preheating and partially drying coal that can be added to existing coke oven structures.

Abstract: Double heating flues are arranged transversely to the horizontal axes of coke oven chambers within heating walls therefor. Side walls between each double heating flue have an internal passageway in the lower part communicating by exit orifices at vertically-spaced locations with the heating flues at the opposite sides of the side wall. The lower parts of the side walls converge horizontally into side wall portions some of which abut against the vertical heating wall and others extend through the vertical heating wall in an alternating arrangement of superimposed bricks. The upper parts of the side walls extend into load-bearing contact with the roof for the coke oven chambers. In the heating walls, three identical stretcher bricks in each course interlock by tongue-and-groove abutment joints. The middle brick abuts in a symmetrical relation with a flue side wall.

Abstract: This invention provides a furnace system for and method of melting metal charges which utilizes hot gases generated by a burner, and are ordinarily discharged from the furnace as waste, for the dual purpose of preheating metal to be subsequently melted and preheating combustion air which is used to provide more efficient operation of the furnace burner.

Abstract: A method of heating up to working temperature from cold, a furnace of the regenerative or recuperative type having its interior lined with refractory material, which method comprises projecting into the furnace from one or more substantially non-radiant high velocity burners a flow of hot gases, causing said gases to circulate around said interior to heat same substantially uniformly, introducing to said interior air (preferably from the normal firing system of the furnace) alternately via one and then the other of the regenerators, and controlling said burner or burners to cause it or them to pass to an excess fuel condition by which said air is consumed within the furnace, thereby pre-heating the furnace and the regenerators up to full working temperature.