Abstract: A heat generator comprising a fuel supply chamber (7a), having at its lower end an inwardly tapered section (12), comprising at its lower end a burner plate (14) with mixing strips (33) and a combustion pipe (20), said tapered section (12) being provided with apertures (8) for primary air in its upper part, apertures (13) for secondary air at a level just above the level of the burner plate (14) and apertures (22) for tertiary air at a level just below the level of the burner plate (14) at the level of mixing strips (33). Preferably all air supplies are preheated. The combustion pipe (20) stands in closed connection with an outlet-pipe, preferably provided with an adjustable ventilator.

Abstract: Description is of fluidized bed shell boiler arrangements in which the sides of the bed within the furnace tube are generally vertical, being provided by vertical walls within the furnace tube. The bed walls may include water tubes or be substantially vertical portions of arcuate panels mounted within the furnace tube. Fluidizing gas is fed to fluidizing gas ducts communicating with the bed from a plenum chamber including paddles movable into positions closing off at least some of the ducts during initial start up of the boiler to reduce the amount of combustible gas (or hot gases) fed to the ducts when heating the bed to its operating temperature. The ducts may be formed by mounting halfround or U-shaped member on the bottom of the furnace tube, the ducts tapering along their lengths such that the gas passing into the bed exits at substantially the same velocity across the width and length of the bed.

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.

Abstract: An installation for gasifying coal in a fluidized bed under high pressure has a vessel resistant to the high pressure and a reactor disposed in the interior of the vessel and having a principal chamber constituting a gasification chamber which permits the establishment of a principal fluidized bed of substantial depth and an auxiliary fluidized bed of a smaller depth. An inclined traveling grate forms the bottom of the gasification chamber and has a lower grate portion supporting the principal fluidized bed and an upper grate portion supporting the auxiliary bed situated in a space between the vessel walls and the gasification chamber. The principal and auxiliary fluidized beds are maintained in hydrostatic equilibrium.

Abstract: A water gas furnace comprising an outer container to provide a housing in which coke is placed into its lower part. A water container is placed within the housing. The coke is ignited and heats the water in the container converting it into steam. The steam is ejected into the coke, which together with air, produces water gas. Preferably, pumice stones are placed above the coke. The water gas is accepted into the pores of the pumice stones, where the heated pumice stones ignite the water gas, producing heat. The heat is extracted by a heat exchanger provided about the housing.

Abstract: A fluidized bed furnace and boiler for the combustion of flyash with a moisture content of 45% by weight. The flyash is produced as a by-product of a coal gasification process and transported in water to a slime dam. From the slime dam a slurry of flyash and water is initially thickened in a gravity thickener (1) (FIG. 1) and then converted to filter cake in a tubular filter press (4). The filter cake is fed through pressurized hoppers (8) and chutes to the base of the boiler (10) and is distributed across the floor through chutes in the side walls and through chutes surrounded by a tubular array of water tubes and extending into the boiler furnace chamber terminating approximately one quarter of the furnace width from the side walls. A fluidized bed with a depth of about 3 meters is formed by discharging air heated in an associated air heater through nozzles in the floor of the furnace chamber to effect combustion.

Abstract: A boiler comprising a fluidized bed combustion chamber which communicates with an exchange enclosure containing water tubes heated by the combustion tubes and within which is arranged an exchange and dust removal chamber equipped with water tubes and containing a vertical internal partition dividing it into two half chambers communicating with one another. One of these half chambers communicates with the upstream part of the enclosure through an inlet orifice situated at the top part and constrains the fumes to follow a descending path along the partition, while the other communicates with the downstream part of the enclosure through an outlet orifice situated at the top part and constrains the fumes to follow an ascending path.

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: The disclosure herein describes a furnace for consuming solid fuel, such as wood, which comprises a gravitational feed chute for feeding the solid fuel in a combustion chamber; the chute has an open lower feed end adjoining the combustion chamber, the feed end being equipped with a plurality of flexible spaced retaining elements which serve to support the load of solid fuel in the chute; air nozzles are provided in the combustion chamber facing the feed end of the chute to create a circulation forcing combustion gases to pass through a zone of high temperature in the combustion chamber.

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.

Abstract: This invention relates to an improvement in direct contact water heaters and in methods of effecting heat exchange between hot gas and cold water. In a typical direct contact water heater cold water is sprayed downwards within a main chamber where it meets hot gas passing upwardly in a counter-current fashion. A direct contact water heater according to this invention includes an antechamber through which the hot gas is passed before entering the main chamber. The hot gas passing upwardly in a counter current fashion to hot water which is at a temperature higher than the dew point of the gas raises the dew point of the hot gas before it enters the main chamber so that the cold water entering the main chamber is heated in an efficient manner to higher temperatures than could previously be effected.

Abstract: In an improved refuse incineration system, wet refuse is heated in a dryer (4) to remove most moisture therefrom while converting such moisture into steam for use in order to save energy consumption in a steam generating plant. The dried refuse is then fed into a boiler (23) for combustion where, because it has been dried, the combustion gas temperature within the boiler is greatly increased and thus the thermal efficiency improved.The preferred form of the system includes additional devices (27, 38) for preheating air used to support combustion of refuse enhancing the extent of combustion of combustible matter in the refuse. The preferred system also including devices (34, 29) for increasing the recovery of residual heat content from the waste stack gas.

Abstract: A novel steel construction solid-fuel firing boiler for civil heating applications comprises a space portion defined by side, bottom, cover, front and rear walls forming therein an interspace for water to be heated, a firestone block burner in the space portion separating a fuel containing upper zone and a lower zone where a flame extends and flue gas is conveyed, the burner defining at a top face thereof a housing with a bottom hole for communicating the upper and lower zones and accommodating therein a refractory material body having a structure for holding overlying embers. The housing bottom and the refractory material body define a channel opening at the hole and communicating with an air distribution chamber in the front wall for conveying secondary combustion air.

Abstract: Disclosed is a heating device of assembled cast panel construction with flanges joined together and whose front, side, back and top walls and bottom grates define a combustion chamber. The angled side walls define an obtuse interior angle and the side and top walls define an obtuse interior angle. An embodiment of the heating device is a boiler incorporated by operatively connected expansion tank, holding tank and a coil of water tubes disposed in the combustion chamber's top area. Another embodiment of the heating device is a hot-air furnace incorporated by a plenum chamber, cold-air return and blower fan with such blower fan directing cold air from the cold-air return to and through the plenum chamber where it is heated. A still further embodiment combines the boiler and hot-air furnace with such heating device.

Abstract: A method for generating steam by a high pressure, high intensity, or high heat release method of combustion in an elongated combustion zone having upstream and downstream ends and an intermediate location and utilizing a normally-solid fuel which produces non-combustible solid residues in which the fuel is introduced axially and a volume of air, at least equal to the stoichiometric amount, is introduced as an annular, rotating stream to produce a rotating vortex of fuel and air, such introduction and flow through the combustion zone being carried out in a manner to collapse the vortex and create plug flow at the intermediate location, burning the fuel and air to produce flue gas at a heat release rate of at least 7 MM Btu/hr, abruptly terminating combustion by the introduction of water, vaporizing the water to produce a mixture of flue gas and steam, and separating solid residues therefrom.

Abstract: The specification describes arrangements in which the attemperation or control of the temperature of a fluidized bed in a fluidized bed combustion unit effected by means of the mixture of a variable proportion of inert gas with fluidizing air fed to the bed may be supplemented with steam. Supplementation with steam being effected to a relatively minor extent during normal operation of the unit but being effected to a major extent when the temperature of the bed passes outside the range at which attemperation may be effected by use of recycled flue gas. The combustion unit is described in use within an arrangement including process plant in the form of a rotary drum dryer.

Abstract: Method of improving the operation and efficiency of a steam generating furnace fired with high moisture content fuel, comprises providing a drying shaft parallel and offset from the combustion chamber of the furnace; wet fuel is introduced into the upper portion of the shaft while a portion of the hot products of combustion gases from the upper portion of the combustion chamber are also permitted to flow into the upper portion of the shaft. The hot gases evaporate moisture from the fuel and are simultaneously cooled thereby so as to increase in density and fall by gravity within the shaft co-currently with the fuel for recirculation into the lower portion of the combustion chamber while the at least partially dried fuel is deflected from the bottom of the shaft into the lower portion of the combustion chamber along with the recirculated gases.

Abstract: A wood-fired boiler construction is shown having a firebox (15) mounted on a metal base (12) and concrete slab (11) in an insulated shed (13). The firebox is a generally box-like structure constructed from spaced, metal tubular members (16) of generally rectangular cross section, the tubular members each having the wider cross-sectional dimension thereof in the plane of a respective wall. The tubular members are interconnected to provide a free flow of fluid throughout the walls of the box-like structure, and spaces between the tubular members are covered by metal plates overlying and connected to the outer sides of the walls. A fluid storage tank (30) is mounted above the firebox and is interconnected to the firebox to provide a flow of fluid therebetween. The firebox is provided with a door and a chimney, both having dampers therein to control combustion.

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: A steam generating unit using gas recirculation (28) for steam temperature control, where the recirculated gases are introduced (38) into the furnace (12) through the bottom opening (34) through which the ash is discharged. Dampers (40) are positioned in the gas recirculation duct (28) for controlling flow therethrough.

Abstract: An improved heating unit comprises a combustion chamber which includes a fuel-supporting perforated burning platform located a distance from the bottom of the combustion chamber. A perforated air plenum is disposed within the combustion chamber a short distance from the combustion chamber top wall to overly a portion of the burning platform. A blower forces air upwardly through the perforations in the burning platform to facilitate waste material combustion and the blower also forces air downwardly through the plenum perforations against the burning platform to further oxygenate the flames and thereby achieve nearly complete combustion. The pressure of incoming air into the combustion chamber forces the exhaust gases through the air passageway above the plenum and out through an exhaust pipe. A heat exchanger, taking the form of a water jacket, surrounds the combustion chamber to cool the combustion chamber and to recover the heat radiated upon combustion of the waste combustible material.

Abstract: A traveling grate for a furnace. The grate is formed of plural pipes through which flows a cooling medium, in particular water. The grate also includes plural movable chains. Grate plate guide flanges are arranged laterally on the pipes. The guide plates, which are connected to the chain rest on the guide flanges. The upper strand of each movable chain is guided in an additional chain guide. The lower strand serves to move ash which has fallen through the grate away to a collection station.Due to the heat discharge through the pipes, the heating performance of the grate can be increased or at a given heating performance an elevated life span can be achieved. Fluid which can be heated up in the pipes can be used profitably, for example to preheat boiler heat.

Abstract: An energy recovery system for an incinerator. Hot flue gases from the incinerator are discharged into a vertical stack and the lower end of the stack is connected through an auxiliary conduit to a heat exchanger, such as a steam or hot water boiler. An induced draft fan draws the hot flue gases through the conduit and boiler to generate steam or hot water and a damper is located within the conduit. A fuel burner is connected in the conduit and operates to supply heat to the boiler during periods when the incinerator is not operating. A first flow sensing mechanism is located in the conduit upstream of the boiler, while a second flow sensing mechanism is positioned in the stack downstream of the connection of the stack and the conduit.

Abstract: A steam generating furnace which burns high moisture content fuel has a panel of heat absorbing tubes dividing it into two vertical interconnecting passageways: (a) a combustion chamber for burning the predried fuel and (b) a drying shaft for extracting moisture from the fuel. Wet fuel is introduced near the top of the drying shaft. As it falls it is dried by some of the hot gases diverted from the top of the combustion chamber into the top of the drying shaft. The cooling of the hot combustion gases due to evaporation of moisture from the wet fuel causes a difference in density between the gases in the two passageways, creates a natural, unidirectional circulation of part of the combustion gases from the top of the combustion chamber to the drying shaft. Predrying the wet fuel causes the fuel to burn faster and hotter thereby producing a stable and efficient combustion of the wet fuel at higher specific combustion rates.

Abstract: A new and improved stove or furnace for efficient combustion of wood fuel including a vertical feed combustion chamber for receiving and supporting wood fuel in a vertical attitude or stack, a major upper portion of the combustion chamber column comprising a water jacket for coupling to a source of water or heat transfer fluid and for convection circulation of the fluid for confining the locus of wood fuel combustion to the bottom of the vertical gravity feed combustion chamber. A flue gas propagation delay channel extending from the laterally directed draft outlet affords delayed travel time in a high temperature environment to assure substantially complete combustion of the gaseous products of wood burning with forced air as an actively induced draft draws the fuel gas and air mixture laterally through the combustion and high temperature zone.

Abstract: This invention is a non-fossil fuel fired hot water system which allows a large amount of water or other liquid to be raised to a relatively high temperature, but below the boiling point, in a relatively short period of time. Due to a unique air circulation system, extremely high temperatures of the combustible material can be obtained with secondary burning eliminating all visible particulate material from the exhaust stack of the system. The unique firebox itself is disposed such that it is surrounded by water on all sides including the access closures for said firebox.

Abstract: A boiler which is designed to be fired by oil and/or gas comprises a water cooled combustion tube closed at one end and located within a water space of the boiler, is connected to a solid fuel fired boiler by an auxiliary furnace having a combustion chamber with means to introduce solid fuel into the combustion chamber, and an opening in the wall of the combustion chamber, the opening having an extension nozzle extending therefrom whereby hot gases may pass from the extension nozzle of the furnace into the combustion tube of the boiler at a position intermediate the ends of the combustion tube.

Abstract: Moisturized hot air having a high temperature and a high humidity is produced by mixing high-temperature combustion gas with low-temperature steam.A low-temperature steam chamber generates low-temperature steam under low pressure and low temperature. A combustion chamber furnishes heat for steam generation to the low-temperature steam chamber. A flue connects the combustion chamber to the low-temperature steam chamber.

Abstract: A steam or hot water generator, operating by solid fuels having high contents in volatile materials, provides that the column of fuel bears on an inwardly inclined grate. A fraction of the carbureting air passes through the grate and fuel, carrying along the volatile products. Another fraction of air, not passing through the grate and accordingly also not through the fuel, but which is however heated by travelling under the grate, joins with the fraction rich in volatile products which is still unburnt, bringing the latter to combustion.

Abstract: A furnace system for automatic, continuous and efficient burning of fragmented wood-type fuel incorporates a wood-type fuel combustion chamber, a fragmented wood-type fuel feeder or conveyor for trickle feeding fuel into the chamber at selected uniform rates, a heat exchanger or heat exchange plenum, igniter for igniting the fuel fragments supported in the combustion chamber, a flame sensor mounted relative to the combustion chamber for sensing the presence of flames from fuel supported in the combustion chamber, one or more blowers providing forced air or forced draft, and a control circuit for controlling and sequencing operation of the elements for the furnace system and for operatively coupling the flame sensor and igniter for switching off the igniter upon sensing of flames from the wood-type fuel.

Abstract: A fluidized bed furnace (10) is provided having a perforate grate (9) within a housing which supports a bed of particulate material including some combustibles. The grate is divided into a plurality of segments (E2-E6, SH1-SH5, RH1-RH5), with the airflow to each segment being independently controlled. Some of the segments have evaporating surface imbedded in the particulate material above them, while other segments are below superheater surface or reheater surface. Some of the segments (E1, E7) have no surface above them, and there are ignitor combustors (32, 34) directed to fire into the segments, for fast startup of the furnace without causing damage to any heating surface.

Abstract: A grateless furnace has a combustion chamber, means to introduce solid fuel into the combustion chamber and to permit said fuel to form a fire bed in the bottom thereof, the combustion chamber being of such configuration that slag formed during combustion of the fuel accumulates under the influence of gravity, at a low part of the bottom of the combustion chamber, said low part having an opening through which said slag may pass for removal from the furnace. The bottom of the chamber may be V-shaped.

Abstract: This invention relates to methods of and apparatus for treating waste products. The apparatus comprises a furnace 1 and a recuperator 2, the furnace comprising at least one rotary section 4 for combustion and/or pyrolysis of the waste products and a stationary section 3 for guiding the smokes generated in the furnace between said rotary section 4 and the recuperator 2. This latter comprises an arrangement 11 -12 for causing the smokes to flow in a state of heat exchange with a fluid 14 for exploitation of the heat thus recovered. A heat-carrier fluid circuit is also incorporated between the walls delimiting the said stationary section 3 and/or the said rotary section 4 of the furnace and the recuperator 2, in such manner that the heat-carrier fluid may transfer the heat it had absorbed during its passage within the furnace walls to the exploitation fluid in the recuperator.

Abstract: Sulfur is readily and efficiently removed from solid fuel in a boiler installation which comprises a hearth for burning and thereby gasifying the solid fuel, the hearth including a grid supporting a fluidized bed of the solid fuel spread thereover, and a tubular boiler body superimposed on, and integral with, the hearth, the boiler body including a lower portion receiving the gasified fuel from the hearth, an upper portion, a common transverse wall dividing the tubular boiler body into the lower and upper portions, and a burner extending into the upper boiler body portion near the dividing transverse wall and receiving a supply of secondary combustion air. A conduit connects the lower boiler body portion to the burner for feeding the gasified fuel therefrom to the burner, and dust removing and desulfurization cyclones in the conduit remove dust and sulfur from the gasified fuel.

Abstract: A stove in which the fuel is combusted within a primary combustion zone and the products of combustion are transported into a tertiary combustion zone surrounded by a container of water. A bundle of secondary combustion tubes connect the primary and tertiary combustion zones. The tertiary combustion and separation chamber termed a posatron completes the combustion and separates a portion of the creosote and other condensable materials from the combustion gases. The combustion gases are then conducted through small pipes immersed in the water bath to cool the combustion gases and complete the condensation of water, creosote and other unburned constituents. The water and creosote mixture flows into a creosote collection chamber and the products of combustion are either recycled to the combustion chamber or exhaused to the atmosphere. Heat is removed from the system by recirculating air or by hot water circulation.

Abstract: A water heating system for use with an incinerator. The incinerator includes a combustion chamber to burn waste material and a stack is connected to the combustion chamber to discharge the hot flue gases. Located within the stack is a heat exchanger. A water heating system is located within a building and includes a closed conduit having a pump to continuously circulate hot water through the conduit. A second conduit connects the first conduit with the heat exchanger in the stack and a second pump is employed to circulate water through the second conduit. In addition, a bypass is connected across the second conduit. A valving system is operable during periods when the incinerator is not operating to flow water through the first conduit and to separately flow water through the second conduit via the by-pass, so that water will continually flow through the heat exchanger.

Abstract: A solid fuel burning hot water heater is described having a primary combustion chamber with a refractory material base portion which forms the locus of combustion. A water jacket defines an upright portion over the refractory base portion for receiving a charge of fuel in a generally vertical stack. The water jacket is coupled to a source of water for at least convection circulation and assists in confining the locus of solid fuel combustion to the base of the chamber. Heat exchange channels or pathways are defined around the outer periphery of the water jacket in heat exchange relationship with the water jacket for transfer of heat from the end products of combustion to the circulating water. A flue gas delay channel arrangement extends from the draft outlet at the base of the combustion chamber to the heat exchange pathways.

Abstract: A liquid or solid fuel-fired boiler for a central heating system is disclosed comprising a combustion chamber and a heat exchanger arranged therearound and connected in a heating fluid circuit comprising an upper header and a lower header interconnected by straight, parallel spaced apart tubular elements for communication therebetween. The tubular elements are disposed along the lateral sides and the back side of the boiler and are embedded in refractory material. Cylindrical interstitial spaces are formed between the tubular elements and the surrounding refractory material to prevent stresses. Flow passages between the tubular elements and the headers are of progressively decreasing cross-sectional area from the back to the front of the boiler thus improving heating fluid flow and temperature uniformity. The lower edge of a cowl defines a throttle passage with the refractory material to control the flow of flue gases to the flue duct.

Abstract: A compact and modularized boiler is comprised of interconnected modules. h module is removable and replaceable with an identical module for easy on site repair. The modules are separated physically and in function as a supercharger module connected to provide compressed air; a burner module connected to receive fuel and compressed air for combustion; a furnace module housing a combustion chamber for receiving hot gas from the burner module and water to be heated from a pump module; a steam drum module for separating liquid and steam; a superheater module interfaced with the furnace module for generating superheated steam; and a convection module for providing additional surface area for heat transfer from the hot gas to the working liquid. The boiler is compact and modular.

Abstract: The invention concerns a heating boiler operating on solid, comparatively finely divided fuel, such as chips or peat, and which is used to produce hot water or steam. The boiler comprises a furnace, in which the grate consists of a shell-like burning basket, which can be placed in rotary motion about its substantially horizontal axis. The rotating of the burning basket may be arranged by connecting to the basket a tubular arm provided with a gear wheel and which is connected to a motor placed outside the boiler. The arm then simultaneously serves as duct through which the fuel is introduced into the burning basket. The purpose of the rotating burning basket is to boost the combustion reaction so that comparatively wet fuel can be used in the boiler. The combustion may furthermore be boosted by placing the burning basket in the furnace in a housing having as its extension a cyclone constituting a helical exhaust duct for the flue gases, which sets the gases at high temperature into strongly turbulent motion.

Abstract: An exterior wall of the firebox of a wood burning stove or the like fixedly supports in close heat exchanging relation therewith a plurality of aluminum fins comprising plates arranged in close side-by-side, substantially coplanar and parallel relation. A single continuous jointless tube of relatively stiff, heat conductive material is bent in a serpentine shape with elongate substantially parallel legs each fixed to the exterior face of a respective plate. The serpentine tube is in contact with said plates except where bent to extend from the end of one plate to the next. In a preferred embodiment, a cover is fixed with respect to and overlies the fins and serpentine portion of the tube, with the ends of the tube extending outward therefrom for connection through water lines to pump and valve apparatus associated with a tank of water to be heated.

Abstract: Energy and useful products are recovered from plantain wastes in a self-contained waste treatment plant wherein the raw material waste is charged into a boiler where the same is combusted to produce flue gases containing several organic compounds and dry ash containing residue mineral salts. The flue gas heats water in a water reservoir to generate steam which drives a turbine generator to produce electricity, the flue gas then being collected and at least partially condensed to form a pyroligneous acid solution from which alcohols and the like can be recovered. The dry ash containing residue mineral salt is mixed with other minerals or reagents with the resulting mass being supplied into a continuously stirred fusion furnace situated within the boiler to which heat is supplied by the flue gas to produce commercially useful products, such as zeolites, dolomite or other related products.

Abstract: A burning cell for solid waste fuel materials comprises a lower cylindrical chamber where a pile of said waste fuel is burned with the aid of a plurality of horizontal arrays of tuyeres that feed the air against said pile, and an upper cylindrical chamber separated from said lower chamber by a centrally opened partition, said upper chamber having a helical array of downwardly inwardly and sidewardly inclined tuyeres to produce an outer descending whirlpool of air which reverses direction at said partition to form a central ascending whirlpool of air, said upper chamber having a centrally opened roof for exhausting said air, whereby the large particle fuel is totally burned in said pile in the lower chamber, whereas the partially burned fines are entrained by the air from said lower chamber tuyeres and passed upwardly into the central ascending whirlpool through said upper chamber to furtherly burn said fines without any contact between said fines and the walls of said upper chamber.

Abstract: A combustion apparatus and a process used to obtain hot water without producing any pollution therefrom, including a hermetic casing, a furnace and cyclone device, all of which are disposed in the hermetic casing. The furnace being designed to combust a waste material and the exhaust gases including dust being introduced into the cyclone device to eliminate the dust. The hot water is obtained by surrounding the furnace and cyclone device with a space including water which contacts directly to the heated walls thereof.

Abstract: The furnace has a feeding channel (4) through which firewood is transported into a fire chamber (3). A steam pipe (10) leads into the channel (4). Through said pipe (10), steam is introduced into the solid fuel material in bursts as soon as a certain temperature is exceeded within the said channel (4). The steam increases the humidity in the air and the moisture of the firewood, thereby reliably preventing a spreading of the fire within the feeding channel (4), without simultaneously impairing combustion within the fire chamber (3).

Abstract: A solid fuel burning device having a combustion chamber and a heat exchange chamber. The two chambers are joined by a tunnel composed of refractory material through which hot flue gases pass from the combustion chamber to the heat exchange chamber, causing the tunnel walls to be heated to the point of incandescence. As the flue gases pass through the tunnel there is a substantial reduction in uncombusted material by pyrolysis. The tunnel has an outside wall adopted to transmit energy by radiation.

Abstract: A furnace for burning dry or wet wood waste products such as hogged bark and the like is provided with a grating therein comprised of aligned rows of bricks resting on supporting cross beams, with at least some of the rows of bricks maintained a uniform distance from other rows of bricks by spacers disposed between such spaced-apart rows of bricks. The furnace is charged by turbulent air entering both above and below the grating, with a select portion of such air being pre-heated. A temperature gradient is established between an area immediately beneath the grating and the area above the grating in the range of 2200.degree. F. and can be controlled by selected initial placement of the bricks and spacers to achieve an optimum cross sectional area for flow of heated, turbulent air through the grating to produce a temperature for efficient heating, drying and burning of wood waste products in an essentially pollution-free manner.

Abstract: A furnace for burning dry or wet wood waste products such as hogged bark and the like is provided with a grating therein comprised of aligned rows of bricks resting on supporting cross beams, with at least some of the rows of bricks maintained a uniform distance from other rows of bricks by spacers disposed between such spaced-apart rows of bricks. The furnace is charged by turbulent air entering both above and below the grating, with a select portion of such air being pre-heated. A temperature gradient is established between an area immediately beneath the grating and the area above the grating in the range of 2200.degree. F. and can be controlled by selected initial placement of the bricks and spacers to achieve an optimum cross sectional area for flow of heated, turbulent air through the grating to produce a temperature for efficient heating, drying and burning of wood waste products in an essentially pollution-free manner.

Abstract: A method and system for controlling the combustion of, for example, coal or bark in a stoker boiler or black, liquor in a recovery boiler to provide operation at maximum efficiency. Control loops are provided for primary or undergrate air and secondary or overfire air. The undergrate air control loop is adjusted as a function of carbon dioxide or steam/fuel ratio, and the overfire air control loop is adjusted as a function of carbon monoxide. In addition to carbon monoxide, combustibles and opacity may be used. Air redistribution is also used to minimize combustibles or CO or opacity.

Abstract: A portable power plant for combustion of solid fuels with contiguous generation of steam and power, wherein the plant is constructed with a low-profile, contiguous dual stage combustion chamber and adjacent dual stage boiler chamber for controlled pyrolysis burning of low B.t.u. solid fuels, the plant having controlled gas and air flow for phased burning and cycling of combustion products with capture and utilization of system generated heat for air and fuel preheating, the plant being constructed for vehicle carriage for mobility to the fuel site.