Abstract: A garbage to hydrocarbon fuel conversion system is provided which generates electricity and hydrocarbon gases from combustible garbage. The garbage is pulverized and then burned in a destructive distillation process. The heat produced is used to generate electrical power. Dust precipitated by an electrostatic cottrell precipitator is mixed with light oil and burned in an oil burner. The heat obtained is used to maintain the destructive distillation. The gases which rise to the top of the precipitator are passed through a hydroxide solution which leaves a layer of tar and oil floating on top of the solution and a volume of hydrocarbon gases on top of this layer.

Abstract: The burner apparatus of the instant invention includes a forced air gas burner which directs a hot gas stream over an object to be cleaned in a burning chamber. The burning chamber includes a burner pipe for evenly distributing the gas stream throughout the chamber. An object-carrying basket is removably mounted in the chamber. A pollutant reduction chamber is connected to a burning chamber outlet and is constructed to reduce the content of pollutants in the gas stream which is subsequently released into the atomosphere.

Abstract: An incinerator for combustible waste materials including a combustion chamber having a side charging entrance with a base no lower than the mid-plane of the combustion chamber. A ram moves waste materials in an elongated hopper connected to the side charging door into the combustion chamber. A fire door is raised to open the charging entrance and lowered to seal the charging entrance. An elevator positioned under the hopper is charged with waste materials and raised to the level of the hopper until the platform of the elevator becomes the bottom of the hopper on a horizontal level with the base of the charging entrance. An after burner unit can be positioned over the combustion chamber. A heat recovery unit is positioned over the after burner to recover heat from the combustion for use in an outside heating unit.

Abstract: A controlled air incinerator includes a primary and secondary combustion chamber. Combustion by-products from the primary chamber are exhausted to the secondary chamber. In the secondary chamber a source of auxilliary heat is provided to maintain the temperature in that chamber at a point which is sufficiently high to fully combust any particulate and unwanted gaseous matter. The secondary combustion vessel is provided with a baffle means for increasing the residence time of combustion by-products in the secondary chamber. The baffle means comprises an arch preferably oriented concave downwardly, the inlet to the secondary chamber being situated beneath the arch. The baffle means means increases residence time and increases the turbulence of gases passing through the secondary chamber.

Abstract: A novel heat exchanger for recuperating heat from a combustion gas stream is disclosed. The heat is recuperated in a steam generator formed from a shell and tube heat exchanger. To reduce deposits on the combustion gas side of the heat exchanger the tube walls are porous so that the pressure across the tube walls during steam generation will continuously drive a small amount of water or steam from the liquid side to the smoke side to remove deposits on the tubes.

Abstract: A method of incinerating in a main combustion chamber leading directly to two consecutive reburn stages. The main combustion chamber accepts bulk refuse onto a hearth floor. In the first reburn tunnel, a burner maintains the temperature of the gases above a predetermined set point. Above that set point, the burner assumes a low setting. Below it, a high setting increases the heat produced. Alternatively, the gas may go to its high setting below a first set point; to its low setting above a second set point; and proportionate at temperatures between them. This chamber also receives outside air to assist in the actual combustion process. From the first reburn chamber, the gases go to a second reburn chamber to complete the combustion. There, they receive additional oxygen for this purpose. At temperatures above a set point determined near the third chamber, additional air enters to prevent excessive temperatures. Fume burning of hydrocarbon containing gases may also take place in the double reburn tunnel.

Abstract: An incinerator system includes a main burner chamber and an afterburner or recirculating burner chamber which forms a kinetic venturi action to insure intermixing of burning gases for substantially complete combustion. The gaseous effluents from the main burner are caused to be rotated in a vortex or tornadic action along a substantial right circular cylinder secondary burner chamber while a burner utilizing external fuel directs flame in the center of the tornadic flow as the effluents and burning gases move from one end of the secondary burner chamber to the other. A portion of the hot gases is recirculated into the main burner chamber.

Abstract: A waste material incineration system (10) and method of combusting waste material is provided wherein system (10) includes a longitudinally directed furnace (14) having a first combustion zone (42) and a second combustion zone (44). Waste material or other fuel is inserted into furnace (14) through a furnace inlet (26) and passes by gravity assist into a vortexing pattern dependent upon the geometrical contouring of the internal walls of furnace (14) in combination with preheating air conduits (86, 88 and 90). Subsequent to vortexing in the first combustion zone (42), the substantially fully combusted gases are transported through second combustion zone (44) for insert into a heat exchanger unit (12) and then passes to a scrubber unit (34) where the exhausted gases are further cleansed to expulsion of the cleansed exhaust gases through an exhaust stack (16) to the ambient atmosphere.

Abstract: Apparatus for combustion of methanol and similar fuels comprising first combustion apparatus receiving a supply of methanol or similar fuel for heating thereof and removing the water content thereof, thereby producing steam, second combustion apparatus disposed above the first combustion apparatus and in fluid communication therewith for combustion of hydrocarbon fuel resulting from the operation of the first combustion apparatus; and utilization apparatus receiving steam from the first combustion apparatus.

Abstract: An improved biomass gasifier combustor system including a furnace, a screw feeder system for feeding a biomass fuel to the furnace and a venturi eductor system adapted for drawing a gaseous combustion product from a combustion chamber of the furnace is disclosed. The furnace enclosure forms a principal chamber in which a housing containing a secondary air chamber is disposed so as to form a partition in the principal chamber which divides the principal chamber into two regions, one of which regions is a gasification chamber and the other of which is a gas combustion chamber.

Abstract: A fluidized bed combustion system for burning fuel particles, such as coal. The system includes a housing defining a first combustion region. An endless, flexible, perforate belt is shiftably mounted in the housing for supporting coal particles of relatively large size. A blower below the belt creates fluidized air which entrains smaller coal particles in a fluidized bed above the larger coal particles. The combustion gases arising due to combustion of the coal particles passes through a secondary combustion region in which coal fines are burned. The combustion gases continue upwardly through a scrubber in which limestone particles are entrained in the combustion gases to strip sulfides therefrom. The limestone particles are regenerated by a cyclone separator while the combustion gases travel through a passage containing boilers or other heat exchangers, whereby the heat from the combustion gases is transferred to fluids in the boilers.

Abstract: A method of afterburning flue gases comprises passing impure gases from, for example, an incineration plant such as a destructor, process furnace, crematory furnace or heating boiler, through a burner in an afterburner where through enforced mixture with combustion gas they undergo complete combustion. The combustion gas, depending on the composition of the flue gases, may comprise air or oxygen or either mixed with petroleum gas. In apparatus for implementation of the method, the flue gases and the combustion gas are introduced into a burner which blows the gas mixture into a flame bowl where temperatures in the range of from 1,500.degree.-2,000.degree. C. can be achieved. In one embodiment, the burner produces a conical basket-shaped flame in which the flue gases undergo complete combustion.

Abstract: In one embodiment, the incinerator has three or more aligned stationary, vertical adjacent structures, each of which has a heat-exchange section covered partially by respective plates which are so arranged as to provide between adjacent ones of the sections substantially uniform gas flow paths via a common combustion chamber disposed above all of the sections. In another embodiment, generally cylindrical vertical and aligned sections are provided, each having a heat-exchange bed supported on a perforated member. The level of the heat-exchange elements in each section is kept very low. The tops of the three sections communicate with one another via a generally horizontal, combustion passageway formed between them into which at least one burner is placed.

Abstract: A process for controlling a calciner system is disclosed wherein the temperatures of the calcined product and the flue gas, and the rate of fuel flow to the burner are measured. A fuel flow set point is determined from the product and flue gas temperatures and the rate of fuel flow to the burner is controlled to the set point.

Abstract: A liquid waste feeding system to be used in conjunction with a solid waste, pyrolytic incinerator. The liquid waste is atomized and injected into the upper end portion of the pyrolysis chamber of the incinerator through a retractable nozzle assembly. The nozzle assembly is automatically extended into the pyrolysis chamber during periods when the liquid waste is to be supplied to the incinerator, and is retracted to a location outside of the chamber when liquid waste is not being supplied. The feed rate of the liquid is controlled by the incinerator stack temperature and modulates between two temperature set points. At the upper set point, the feed rate decreases on temperature rise, which will occur when burning liquids with high BTU values. At the lower set point the feed rate decreases on temperature drop, to insure that minimum combustion temperatures are maintained in order to achieve complete burnout in the incinerator thermal reactor.

Abstract: The incinerator comprises a dome-shaped furnace containing a fire brick retaining wall, which has an upper edge spaced just beneath the curved ceiling of the furnace, and which divides the furnace into a large primary combustion chamber, and a smaller secondary combustion chamber. A plurality of perforated air-supply tubes are mounted in the primary chamber above a pathological hearth, which is mounted adjacent the bottom of the primary chamber to extend horizontally between the retaining wall and one side of the furnace. Combustion by-products created in the primary chamber pass over the top of the retaining wall, and then downwardly through the secondary combustion chamber and through an opening in the bottom thereof to one side of a discharge duct, which extends beneath the hearth to communicate with a smoke stack that is mounted at the back of a furnace.

Abstract: A waste material incineration system (10) and method of combusting waste material is provided wherein system (10) includes a longitudinally directed furnace (14) having a first combustion zone (42) and a second combustion zone (44). Waste material or other fuel is inserted into furnace (14) through a furnace inlet (26) and passes by gravity assist into a vortexing pattern dependent upon the geometrical contouring of the internal walls of furnace (14) in combination with preheating air conduits (86, 88 and 90). Subsequent to vortexing in the first combusion zone (42), the substantially fully combusted gases are transported through second combustion zone (44) for insert into a heat exchanger unit (12) and then passes to a scrubber unit (34) where the exhausted gases are further cleansed to expulsion of the cleansed exhaust gases through an exhaust stack (16) to the ambient atmosphere.

Abstract: An incinerator with a main combustion chamber leading directly to two consecutive reburn stages. The main combustion chamber accepts bulk refuse onto a hearth floor. Air jets within the floor and near the roofline provide a generally stoichiometric amount of air for the burning refuse. Of this air, 75% emanates from the nozzles located in the floor. For the designed amount of refuse, the main chamber has a sufficient area to maintain the ratio for the expected heat to the square area to less than about 100,000 Btu/sq.ft. hr. Similarly, the ratio of the main chamber's volume is less than about 12,000 Btu/cu.ft. hr. The combustion gases pass from the main chamber into a first reburn stage. The throat between the two sections introduces the gas into the latter at an angle of about 60.degree. relative to the direction of travel in the reburn section.

Abstract: An incinerator including a housing defining a combustion chamber, a hearth mounted in the chamber, the hearth having a plurality of vertical openings, air passageways in the hearth each communicating with at least one of the vertical openings, a burner mounted in the housing below the hearth, and an exhaust stacking means for conducting combustion gases into the atmosphere.

Abstract: In a thermal regeneration anti-pollution system in which there are a plurality of heat-exchange beds communicating with a high temperature incineration zone, excessive temperatures in the zone and danger to equipment in the installation are prevented by drawing off at least part of the hot gases therein. The gases are by-passed around the heat-exchange bed through which they would normally flow and then mixed in the exhaust with those incinerated gases which have been cooled through their normal passage through a heat-exchange bed.

Abstract: Disclosed are methods and apparatus for incinerating self-burning wastes by igniting the waste materials in a first chamber and limiting the supply of air in the first chamber to control the rate and temperature of combustion. The partially oxidized gasses produced in the first chamber are conducted to a second chamber through an elongated tube. Air is mixed with the partially oxidized gas in the elongated tube and the mixture ignited to complete combustion of the gasses in the tube and the second chamber. Metal wastes may be melted and recovered in the second chamber.

Abstract: Boiler fuel is exposed to a flow of pulsating hot gas and sonic energy from a pulse jet engine for classifying fuel particles with uniform size and moisture content. A second pulse jet engine directs a continuous flow of pulsating hot gas and sonic energy onto those surfaces of heat exchangers which are exposed to the boiler heating gas, for cleaning the heat exchanger surfaces. Another pulse jet engine is disposed in the exhaust stack for heating stack gas, for increasing chemical efficiency of emission control systems, while permitting greater extraction of usable heat from stack gas while inside the boiler.

Abstract: Unit for thermal incineration of non-explosive gases with minor amounts of organic pollutants and for production of hot air, and which can be adapted to various types of supplementary fuel. There is a combustion chamber which consists of a flame pipe inside an outer jacket. Through the space therebetween, incoming process gas is led as coolant. At its front end, the combustion chamber has a burner for supplementary fuel and a mixing-in zone for process gas. The process gas rapidly mixes with the hot combustion gases in the flame, the gas reaching its reaction temperature directly. Powerful turbulence in the mixing-in zone gas, film-layer cooling, convective cooling and even flow give highly efficient and pure combustion while keeping the flame pipe temperature low enough to prevent corrosion.

Abstract: An underfire system for a controlled starved-air incinerator and incinerating process which minimizes high localized temperatures in the main combustion chamber to lessen clinker formation and vaporization of inorganics for minimizing the particulate emission rate and which maximizes conversion of the fixed carbon portion of the waste materials into volatile matter for maximizing the thermal efficiency of the incinerator. The underfire system supplies air at less-than-stoichiometric requirements which creates an exothermic reaction between some of the fixed carbon in the waste material and the oxygen in the air to produce volatile carbon dioxide. In addition, steam is supplied to the burning waste materials, preferably alternately with the air supply, for creating an endothermic "water-gas reaction" between additional fixed carbon in the waste material and the steam to produce volatile carbon monoxide and hydrogen gas and for absorbing undesired heat from the exothermic reaction.

Abstract: An underfire system for a controlled starved-air incinerator and incinerating process which minimizes high localized temperatures in the main combustion chamber to lessen clinker formation and vaporization of inorganics for minimizing the particulate emission rate and which maximizes conversion of the fixed carbon portion of the waste materials into volatile matter for maximizing the thermal efficiency of the incinerator. The underfire system supplies air at less-than-stoichiometric requirements which creates an exothermic reaction between some of the fixed carbon in the waste material and the oxygen in the air to produce volatile carbon dioxide. In addition, steam is supplied to the burning waste materials, preferably alternately with the air supply, for creating an endothermic "water-gas reaction" between additional fixed carbon in the waste material and the steam to produce volatile carbon monoxide and hydrogen gas and for absorbing undesired heat from the exothermic reaction.

Abstract: A rotatable drum is equipped at a front end with a burner for liquid waste materials and at a rear end has a tiltable charging mechanism for solid waste materials and waste materials stored in barrels. The rear end of the drum is sealed by a fixed casing enveloping the charging mechanism. Adjacent that end there is a gas outlet projecting through a dome-like gas inlet connection of a fixed secondary combustion chamber. The drum shell is stepped such that a refractory lining of the semicylindrical lower drum part cooled by means of water spray nozzles is thinner than a refractory brick material of the semicylindrical drum upper part by an amount equal to the depth of the drum step. Due to rotationally reciprocating or rocking movement of the drum, the waste materials undergo pyrolysis, the pyrolysis gases flowing through a gas outlet into the secondary combustion chamber.

Abstract: An afterburner for use as a secondary combustion chamber in a starved-air combustor system to further combust any combustible material in the combustion gas and entrained solid particle material discharge from the combustion chamber of the starved-air combustor system. The afterburner is lined with refractory and includes a diverter plate positioned transversely to the incoming flow of combustion gases. The afterburner is divided into a plurality of reaction zones, each of which has an associated reaction air supply. The diverter plate imparts a cyclonic flow to the combustion gas which is enhanced by air injected in the combustion zones. The temperature of the gas discharged from the afterburner is monitored and the flow of reaction air controlled responsive to changes in discharge gas temperature from a predetermined temperature.

Abstract: The tail gas from a sulfur process is added directly to the fuel gas supplied to an incinerator burner. The H.sub.2 S in the tail gas is converted by the burner to SO.sub.2 to enable the sulfur process to meet environmental air pollution requirements.

Abstract: A cremator is provided with a primary cremation chamber and a secondary cremation chamber adjacent to and in communication with the first chamber. A method of cremating bodies utilizing the apparatus disclosed wherein a body is eighty percent consumed in the primary chamber and is then moved to the secondary chamber wherein it is consumed together with the by-products of the cremation of a second body in the primary chamber. Cremation in the secondary chamber utilizes the heat of combustion of the second body in the primary chamber to increase the efficiency of the system.

Abstract: A hazardous materials incineration system is disclosed which includes a solid waste combustor of the inclined, oscillating or rocking type and a liquid waste combustor suitable to incinerate wastes in liquid form. The combustion products from both the solid waste combustor and the liquid waste combustor are fed to an afterburner which is equipped with burners to maintain elevated temperatures throughout the length of the afterburner chamber. The products of combustion exit the afterburner into a conditioning unit which eliminates larger particulate matter, cools the combustion products and releases certain additives into the moving gas stream prior to entry into a baghouse. All neutralized salts are withdrawn at the baghouse and the gaseous baghouse effluent is directed to a further aqueous liquor contact apparatus prior to exhausting to atmosphere through a forced draft stack system.

Abstract: A method and incinerator apparatus for cleaning and utilizing the waste gases thereof to perform work after the residue and particles that pollute and contaminate the same are removed therefrom. After the waste gases are subjected to and scrubbed at high temperatures to burn and consume the particles and residue, remaining particles and residue are further separated in a heat accumulator from which the higher temperature waste gases are used as an aid in the scrubbing and cleaning the lower temperature waste gases and from which the heat of the waste gases is extracted for the performance of work.

Abstract: In a thermal regeneration anti-pollution system in which there are a plurality of heat-exchange beds communicating with a high temperature incineration zone, excessive temperatures in the zone and danger to equipment in the installation are prevented by drawing off at least part of the hot gases therein. The gases are by-passed around the heat-exchange bed through which they would normally flow and then mixed in the exhaust with those incinerated gases which have been cooled through their normal passage through a heat-exchange bed.

Abstract: A method and apparatus for the heat treatment of industrial wastes wherein at least some of the constituent materials of the wastes are subjected to combustion and/or to pyrolysis to produce flue gases and, in some applications, a residue. The supply of an oxygenated combustion-supporting gas to the wastes is regulated as a function of at least one sensed predetermined characteristic of the flue gases. The oxygenated gas may be a mixture of air and substantially pure oxygen, the feed rate of one or both of these being regulated in response to the sensed temperature and/or oxygen content of the flue gases. Such regulation maintains the oxygen content of the flue gases within the range of from 0 to 7%; and the temperature of the flue gases may be maintained from 400.degree. to 1200.degree. C. and, preferably within a range of 50.degree. C. in this region.

Abstract: A system for the combustion of waste products for the extraction of heat energy in a clean pollutant-free medium. The system includes a swirling air-cyclonic type incinerator having means for controllably consuming fuel in the form of waste products of various grades and heating values. Incinerator outlet means are provided for transmitting gaseous combustion products to a heat exchanger, a filtering device, and ultimately to a point of beneficial utilization. Through a plurality of ducts, control valves, and pumping means, a selectably variable volume of oxygen necessary to support combustion is taken from the ambient. The remaining gas flow to the incinerator for such purposes as creation of a swirling flow and cooling is pumped from the outlet side of the heat exchanger.

Abstract: A control system for multiple burners or heaters in an afterburner section of a metal scrap dryer is provided. The control system provides for cascade and sequential control including selective and sequential ignition as well as selective and sequential deenergization of the burners or heaters.

Abstract: A thermal reductor system is provided with a rotary ignition chamber having an input end, a discharge end of enlarged size relative to the input end and an inside chamber wall having a configuration for promoting natural flow of gases, smoke and ash discharge from the input end to the discharge end. To limit discharge of solid residue to a maximum predetermined size, the discharge end of the chamber is provided with a restricted ash exit. So that the ignition chamber is particularly suited for disposing of liquid wastes in a compact chamber construction, the inside chamber wall has a restriction intermediate the input and discharge ends of the chamber defining a barrier to liquid flow. An exhaust duct is provided for the passage of gases and smoke from the ignition chamber.

Abstract: A method of metering underfire air for increasing efficiency and reducing particulate emissions from wood-fire, spreader-stoker boilers is disclosed. A portion of the combustion air, approximately one pound of air per pound of wood, is fed through the grate into the fuel bed, while the remainder of the combustion air is distributed above the fuel in the furnace, and the fuel bed is maintained at a depth sufficient to consume all oxygen admitted under fire and to insure a continuous layer of fresh fuel thereover to entrap charred particles inside the fuel bed.

Abstract: A waste disposal system for the thermal conversion of municipal and industrial solid wastes into essentially pollution free products of combustion is disclosed. The waste disposal system includes a building enclosure having an interior storage area for accumulating combustible refuse, and an incinerator for thermally oxidizing the refuse. In a preferred embodiment, the incinerator includes a combustion chamber which is maintained at a reduced pressure level relative to the pressure of the surrounding atmosphere. This subatomspheric pressure arrangement produces a positive flow of air into the chamber as it is loaded thereby permitting loading during combustion virtually without risk of injury to personnel or damage to surrounding combustible material. In another preferred embodiment, the incinerator includes a primary combustion chamber which is maintained in an excess air condition as combustion occurs, and a secondary combustion chamber into which an auxiliary source of fuel such as natural gas is injected.

Abstract: This invention relates to a burning furnace of hot gas recirculation type for minimizing fuel cost. The furnace includes a cyclone which receives dust-containing exhaust gases. One or more secondary air-introducing nozzles are provided for the cyclone at top of or in close proximity to the upper end of the cyclone leading concentrically to a flue gas passage such as funnel. Upon introducing secondary air under pressure into the cyclone, a downwardly directing swirling air flow is formed therein for the separation of heavier dust together with part of the fed exhaust gases. The thus separated air-hot gas mixture including heavier dust particles is returned to initial stage of the furnace for the recirculation through the furnace.

Abstract: A smoke control device for use in motor vehicle incineration. Smoke from burning vehicles in an incineration area is directed into a collecting chamber by controlled air flows and flaps. Updrafts evacuate the chamber and force the smoke into a combustion stack. The column of smoke in the stack is raised to combustion temperature by heaters mounted on the stack. The superheated smoke is combined with heated air in the vicinity of an open flame causing combustion resulting in a clear stack discharge.

Abstract: A controlled air incinerator having an increased capacity for burning waste material and having increased efficiency for completely burning all burnable waste material fed thereto. The controlled air incinerator, which is sometimes referred to as a "starved air" incinerator, requires accurate control of burning conditions so as to provide at all times a discharge of clean flue gases free from pollutants. In the present incinerator, means are provided for transferring the waste material therethrough while burning, the means causing the burning waste material to tumble within the combustion chamber and open up so as to expose to combustion air any unburned but burnable parts of the waste material whereby the oxygen of the combustion air will result in complete combustion.

Abstract: A heat producing device utilizing solid carbonaceous material, especially material of cellulosic composition such as corn cobs, as fuel. The heat producing device includes a gasifier for the carbonaceous material. The gas outlet of the gasifier leads to a burner. A cyclonic burning chamber and particle separator are connected to the discharge of the burner. The cyclonic burning chamber and particle separator has a heat outlet and a particle discharge outlet. An adjustable air inlet and mixing chamber are installed in the heat outlet for adding ambient air to reduce the temperature of the heat discharged from the heat outlet. A discharge fan has an inlet connected to the mixing chamber and an outlet for discharging the heat received therefrom to a drying chamber or other heat utilizing source.

Abstract: A pollution control incineration system comprises an elongated duct having one or more inlets positioned at or near grade level. An upright standpipe removably covers an inlet opening to provide a polluted gas inlet to the duct from a location elevated above grade. The duct terminates at its remote end in a combination flue and pollution control system which may include pollution control devices such as an afterburner chamber, a water spray cooling chamber, a baghouse and an induced draft fan. A portable, shell type primary combustion chamber removably overfits the standpipe to allow combustible material to be burned within the shell and to direct the gases of combustion downwardly into the duct through the top of the standpipe.

Abstract: A process for the thermal after-burning of waste gases containing combustible substances capable of forming an explosive mixture with air in a specific concentration range comprises feeding the waste gas undiluted to a flame with a concentration of combustible substances which varies between the lower and the upper explosion limits, feeding the waste gas to the combustion zone at an entry speed higher than 10 m/sec, and discontinuing the supply of waste gas when a limit temperature of 80.degree. C. is exceeded in the waste gas shortly before its entry into the combustion zone.

Abstract: The present invention comprises an improved after burner for a multi-chamber incinerator including a pair of successive gas flow tubes having arcuate surfaces disposed one over the other such that the said one is an arcuate surface having a radius to a longitudinal centerline axis which is oriented in the same vertical plane but offset above the longitudinal centerline axis of the said other of said arcuate surfaces, baffles for directing gas flow including such flow from the first of said tubes to the second of said tubes, ports for ingesting air into said tubes at an angle to the path of gas flow through the tubes and super oxygenating the tubes and burners in the tubes to totally consume combustible pollutants carried by the gas flow.

Abstract: The following disclosure teaches ways and means for incinerating organic wastes in a multiple hearth furnace equipped with an afterburner. In the furnace, the wastes are pyrolyzed in an oxygen deficient atmosphere which is regulated to only partially complete the oxidation of the organic substances which are pyrolyzed from the wastes. In the afterburner, air is introduced to complete the oxidation of the partially oxidized substances carried by gases and vapors from the furnace. The air supply to the afterburner is controlled so that, at temperatures above a predetermined temperature, the quantity of air introduced is increased with increasing temperatures and is decreased with decreasing temperatures. In other words, the pyrolyzing furnace is caused to operate with a deficiency of air over its operating range, while the afterburner is caused to operate with excess air and the amount of excess air supplied is used to control the operating temperature by quenching.