Abstract: In a method for reducing the NOx emissions of a rotary kiln of a clinker production plant, fuel supplied through a burner of the rotary kiln is burned along with primary air fed through the burner, wherein the primary air has a lower oxygen content and the primary air has an oxygen content reduced relative to that of the ambient air and a temperature increased relative to that of the ambient air, and the primary air is obtained by mixing ambient air with exhaust gas from the rotary kiln or from a heat exchanger connected to the rotary kiln and used for preheating raw meal. The primary air is further obtained by mixing with hot air, in particular waste air from a clinker cooler.

Abstract: A device to bring a gas into contact with a particulate solid bulk material, comprising a first and a second tubular, radially gas-permeable element (1, 2) having different diameters and which each define a central axis, wherein one of the elements is essentially coaxially placed in the second element, wherein the elements (1, 2) internally define a ring-shaped shaft (30) for a material (40) that is to be contacted by the gas, wherein the elements have essentially vertically oriented axes, a ventilation device (50) for compelling the gas radially through the shaft and the material, a first device (41) for addition of the material to an upper end of the shaft (30) and a second device (31-36) for output of dried material from the lower end of the shaft. Driving means (12) are provided for internal displacement of the elements (1, 2). At least one of the walls is provided with at least one screw line ramp which maintains a high porosity and a controlled feeding of the material.

Abstract: A multizone convection furnace is provided in which gas from a cooling chamber of the furnace is directed into one or more heat zones of the furnace for the purpose of providing a specified thermal profile. The gas introduced from the cooling chamber into the one or more heat zones is of the same type of gas present in the heat zones, and typically is nitrogen. In a preferred embodiment, the convection furnaces comprises a heating chamber composed of a plurality of adjacent heat zones and a cooling chamber at the exit end of the heating chamber. A conveyer extends through the furnace for movement of a product through the heat zones and cooling chamber of the furnace. The cooling chamber is coupled to one or more of the heat zones such that cooled gas from the cooling chamber can be introduced into selected heat zones. In one version, a cooled gas path is provided to all of the heat zones and cooled gas is introduced into intended zones by opening associated valves.

Abstract: A diffuser plate for a reflow oven includes an upper surface and a plurality of nozzle openings therein. Each of the plurality of nozzle openings has a raised surrounding portion for restricting condensed flux on the upper surface of the diffuser plate from flowing through the nozzles. A drain hole permits condensed flux on the upper surface to flow downward through the plate.

Abstract: An integrated fluidized bed ash cooler for a fluidized bed boiler, particularly a circulating fluidized bed (CFB) boiler, employs at least two fluidized bed sections positioned in series along a solids flow path. Each section contains fluidizing means, the first section along the solids path being separated from a following section with a threshold. The first section contains means for measuring a bed temperature in the vicinity of the fluidizing means and at a higher elevation within the fluidized bed. Means are provided for removing oversized bed material from the first section to facilitate the removal of ash while minimizing the possibility of ash plugging during operation.

Abstract: A rotary kiln for pyroprocessing particulate material includes a cylindrical kiln shell supported for rotation about a longitudinal central axis. The kiln has a plurality of circumferentially spaced peripheral openings provided in the kiln shell near its exit end for discharging pyroprocessed particulate material therethrough. A raised grate disposed over each discharge opening has a generally convex geometric profile that projects into the interior of said kiln shell.

Abstract: The present invention relates to a cooling system of a furnace, more particularly, to a multi-cycle cooling system, located by the furnace door. The multi-cycle cooling system comprises the first gas cooling cycle, the second gas cooling cycle, the first liquid cooling cycle, the second liquid cooling cycle, the heat sinks and the heat insulation slot. When inside the process tube proceeds the high temperature process like depositing process, the first gas cooling cycle and the second gas cooling cycle are opened and the second liquid cooling cycle is closed at the same time. The second gas cooling cycle and the second liquid cooling cycle are assembled in the first flange, which is located on the process tube and contacts with the door. The first liquid cooling cycle in the second flange, which is located on the process tube and contacts with the first range, is always opened.

Abstract: A solder reflow oven for the processing of ball grid array substrates bearing solder balls is described, comprising: input means for introducing substrates into the oven, a processing chamber within which the substrates are subject to a solder reflow process, and output means for discharging substrates from the oven for further processing or handling, and means for transferring the substrates through the processing chamber in a first direction towards the output means. The processing chamber comprises a plurality of heating and cooling zones arranged with a constant pitch in the first direction, and the transferring means is adapted to move the substrates in the first direction in stages, with each component moving a distance equal to the pitch between two zones in each stage, whereby the components are moved from zone to zone in stages.

Abstract: Cooler for combustion products, with a conveyor through which air flows, which cooler is formed by a stationary grate surface (7) and a conveyor (8). The conveyor contains a plurality of drivers (9) moved at a distance from one another over the grate surface. A pre-space (30) is formed at the back of the feed stream fed to the grate (7,8), which pre-space is delimited on the underside by the conveyor (7,8) and accommodates a slope of the products to be cooled. The products in the pre-space are intensively cooled and surround the drivers in a protective manner as the latter enter the hot product bed.

Abstract: A plate globally shaped like an upturned caisson with a bearing surface (10) for supporting and driving forward a bulk material layer to be cooled with a cooling gas passing through the platex. The plate front part (10b), viewed in the material forward motion direction, is formed with overlapping flanges (14) sloping upwards and defining transverse cavities (20) in the bearing surface and the overlapping parts of two adjacent flanges (14) defining narrow channels (22) for the cooling gas to pass through.

Abstract: An annular cooler for a rotary kiln having a series of tubes longitudinally extending parallel to the axis of kiln and radially spaced therefrom. The tubes have flights mounted therein for carrying and moving clinkers discharged from the lower end of the kiln into the tubes and then upward to the upper end of the tubes where they are discharged into an appropriate collecting bin. A cooling medium is drawn downward through the tubes opposite to the direction of travel of the clinkers. The cooling medium which is heated as it travels through the tubes is directed into the kiln upon leaving the cooling tubes for use in the combustion process in the kiln.

Abstract: A method and apparatus for acoustically enhancing cooling of molten liquid. In one embodiment, a cement plant has a mill in which raw materials are mixed and ground into a powder, a kiln in which the powdered raw material undergoes a calcining process and is converted into a molten liquid known as clinker, a cooler for cooling and solidifying the clinker, and a finishing mill for grinding and mixing the clinker with gypsum and/or other raw materials. The clinker cooler has a transport mechanism for transporting clinker from an inlet end to an outlet end and a plurality of fans, located below the transport mechanism, for blowing air up through the transport mechanism and into the bottom surface of the clinker bed. The clinker cooler has one or more horns positioned on the roof of the cooler for emitting acoustic energy into the cooler. A controller controls activation of each horn independently, such that each horn may be operated continuously or intermittently.

Abstract: A cooler (6) for cooling of particulate material which is subjected to heat treatment in the rotary kiln is mounted at the material outlet end (1) of a rotary kiln. The cooler is provided with annular chambers (7, 8, 9) disposed around each other, and which are successively passed by the material from the outlet (5) of the kiln to a material outlet (20) in the stationary housing (15) of the cooler in countercurrent with the cooling air which flows from an air inlet (18) and through the annular chambers to the kiln in which the air thus heated is utilized as combustion air.

Abstract: The temperature of articles in an "environmental" chamber is stabilized by evacuation of the "environmental" chamber, after having stabilized the temperature of such an article to approximate that of a controlled-temperature member spaced from the article by a small gap, to a pressure just sufficient to provide viscous gas behavior, adjusting the temperature of the article to closely match that of the member by gas conduction heat transfer across the gap, and evacuating the chamber to high vacuum.

Abstract: An inlet for a rotary kiln comprises a plurality of arcuate segments supported adjacent the inlet opening of the kiln to form a trough protruding through the inlet opening. Each of the segments is hollow and has an opening through which a cooling medium may be introduced.

Abstract: In a method for cooling a rotary kiln having a cylindrical outer jacket, cooling air is blown at high speed radially towards the jacket from an annular supply-air chamber surrounding the jacket and having a perforated inner wall which is located at a slight distance from the jacket and through which the cooling air is blown towards the jacket. The cooling air is sucked out from the space between the jacket and the inner wall to an annular exhaust-air chamber which is separate from and surrounds the supply-air chamber and communicates with said space. The cooling-air flow through the chambers is adjusted by fan devices connected thereto. A device for implementing this method has an annular supply-air chamber surrounding the jacket and having a perforated inner wall which is located at a slight distance from the jacket and designed for radially blowing cooling air towards the jacket.

Abstract: Cooler pocket grate for use in conveying hot clinker from discharge end of cement kiln to cooled clinker processing area. Alternate stationary and moving grates constructed as stainless steel castings are provided with upper surface ridges having through holes for fan driven cooling air from underlying cooler bed compartments. Intermediate pockets between ridges retain clinker which serves as a grate wear resistant interface with kiln discharged hot clinker conducted along the cooler bed.

Abstract: A revolving grate cooler for cooling of clinker or similar products comprising a tubular shaped body having a plurality of holes. A plurality of curved metal cooling plates having a plurality of openings are secured to a front inner surface of the body, and a plurality of curved plates having smooth surfaces, some of which have outwardly extending projections, are secured to a middle portion of the body. A pressurized chamber communicates with the body to provide air flow through the holes and openings for cooling the products within the body.

Abstract: Therapeutic agent delivery devices and methods for using them in treatment of dental disease are disclosed. In the treatment of periodontal disease, a therapeutic agent such as tetracycline mixed in a polymeric matrix such as ethylene vinyl acetate copolymer is packed into the area to be treated and kept in place for a suitable time, during which the therapeutic agent diffuses out of the polymeric matrix, providing continuous therapy for the treatment site.

Abstract: The present invention concerns a method for transforming a rotary kiln equipped with a planetary cooler and intended in particular for the manufacture of cement, a kiln obtained by this method and a burning line equipped with this kiln, the kiln being constituted by an inclined rotary tube through which the material flows and which is heated inwardly, this tube comprising a downstream section constituting a burning zone having a smaller diameter than that of the upstream section constituting a material preparation zone, both sections being connected by a conical part, and the downstream section having a diameter comprised between 4 and 5,1 meters and a length comprised between 20 and 50 meters.

Abstract: Apparatus for cooling a bed of pyroprocessed particulate material such as lime received from a source such as a kiln, the cooler including a shaft with one or more underlying hoppers through which the material flows as cooling air is forced upwardly therethrough. The invention embodies hoppers with uniform slopes at any given elevation, dual hopper slopes with one being extremely steep, internal flow guiding means, as well as an octagonal or partially octagonal wall configuration and matching scalloped octagonal hoppers. Also included is the concept of providing substantially equal areas of draw in any angular segment about the vertical center line of discharge from a hopper or cluster of hoppers. The resultant is more uniform flow of material down through the cooler and correspondingly more efficient cooling. Alternative embodiments include hopper transition pieces in lieu of the cooling shaft being constructed in an octagonal or partially octagonal configuration.

Abstract: Therapeutic agent delivery devices and methods for using them in treatment of dental disease are disclosed. In the treatment of periodontal disease, a therapeutic agent such as tetracycline mixed in a polymeric matrix such as ethylene vinyl acetate copolymer is packed into the area to be treated and kept in place for a suitable time, during which the therapeutic agent diffuses out of the polymeric matrix, providing continuous therapy for the treatment site.

Abstract: Apparatus for cooling a bed of pyroprocessed particulate material such as lime received from a source as a kiln, the cooler including a shaft with one or more underlying hoppers through which the material flows as cooling air is forced upwardly therethrough. Each of the hoppers has an associated air inlet assembly comprising compactly stacked air inlet rings concentric with and symmetrically shaped to the hopper entry. The air inlet rings are supplied with air from ducts which are provided with dampers by which the amount of air fed to each horizontal cross sectional segment of the hopper can be controlled. A deflector ring formed of an inclined particle flow deflector surface equalizes the rate of draw above by modifying the relative areas affected.

Abstract: Apparatus for cooling a bed of pyroprocessed particulate material such as lime received from a source such as a kiln, the cooler including a shaft with one or more underlying hoppers through which the material flows as cooling air is forced upwardly therethrough. The invention embodies hoppers with uniform slopes at any given elevation, dual hopper slopes with one being extremely steep, internal flow guiding means, as well as an octagonal or partially octagonal wall configuration and matching scalloped octagonal hoppers. Also included is the concept of providing substantially equal areas of draw in any angular segment about the vertical center line of discharge from a hopper or cluster of hoppers. The resultant is more uniform flow of material down through the cooler and correspondingly more efficient cooling. Alternative embodiments include hopper transition pieces in lieu of the cooling shaft being constructed in an octagonal or partially octagonal configuration.

Abstract: A lifting element (5) for pipe coolers for material produced at least partially in lumps, e.g. clinker, has a mounting portion (8) fixed to the shell (1) of the pipe cooler, and a carrier portion (9) which extends essentially at right angles thereto and comprises at least one aperture (15; 24,25) passing through it. It may be of fork-like construction, with each aperture (24, 25) located between two tines (21, 22, 23).

Abstract: A controller for a clinker cooler for cooling high temperature clinker supplied from a rotary kiln by controlling the quantity of high temperature clinker cooling air at a constant value comprising maintaining the pressure at the rear side of a baffle plate mounted in the cooler constant by varying the opening of a damper of a cooler exhaust fan and the rotating speed of the cooler exhaust fan, and controlling the pressure of a kiln outlet hood by the quantity of clinker cooling air of the all air chambers of the cooler except for the first chamber on the kiln side of the baffle plate. Thus, the variations in the cooler exhaust amount and the secondary air flow rate occurring in the prior-art control means are reduced to stabilize the steps, to improve the quality of the clinker and to reduce the thermal quantity consumption per unit.

Abstract: A two stage material cooling apparatus for cooling hot particulate material such as cement clinker discharged from a furnace such as the rotary kiln. The first stage includes a direct heat exchanger such as a reciprocating grate type heat exchanger or an attached tube cooler and serves primarily as a heat recuperator. This cooler acts on the principle of direct heat exchange between cooling gas and the hot material whereby the material is cooled and the gas is heated and returned to the kiln as preheated secondary air for combustion. The second stage cooler is a shaft type cooler with gas permeable sides so that cooling gas passes through the material generally perpendicular to the flow of material. The gas which is supplied to the second cooler can come from recirculated cooling gas or from ambient. The gas discharged from the second cooler can be supplied directly to the gas inlet of the first cooler recirculated to its inlet after passing through an air to air heat exchanger.

Abstract: An apparatus for pack cooling flat stock to be retrofitted to a standard cooling bed. The apparatus includes collecting means having a plurality of stacker arms mounted for movement with respect to the stationary notch bars of the cooling bed between a first, retracted position, in which the arms underlie the notches in the stationary notch bars to permit uninterrupted transport of bar stock across the bed, and a second, lifting position in which the arms can lift a flat bar to a height sufficiently above the uppermost travel of the moving notch bars to permit a successive flat bar being transported across the cooling bed to be received in the notch of the stationary bar just vacated by the flat bar lifted by the stacker arms. Upon the return of the stacker arms to their first position, the flat bar held thereon will be placed on top of the newly-introduced flat bar to form a stack, resulting in a retarded cooling rate for the flat bars in the stack.

Abstract: An arrangement for recovering the sensible heat of dumpable hot stock includes a continuous conveying belt guided about at least two deflection pulleys and formed by articulately connected plates. The carrying run of the conveying belt with the hot stock applied thereon and the empty lower run each are guided through a cooling zone. In order to recover the sensible heat from the hot stock to an extent as large as possible and with a high efficiency, without having to use a bed covering material, the plates of the conveying belt are designed to include at least two layers, an outwardly carrier layer receiving the hot stock and an inwardly arranged insulation layer.

Abstract: Upon leaving the mold, plastic bottle preforms are engaged internally and/or externally by pneumatic suction grips which form an annular chamber (15, 27) through which atmospheric cooling air is circulated. This increases the rate of production of the preforms by cooling them during handling, rather than separately at a discrete cooling station.

Abstract: A conveyor has successive mutually spaced driven rollers in which hot rolled steel rod is transported in the form of overlapping offset rings. The rings are rapidly air cooled by first nozzles which direct first jets of cooling air upwardly to impinge against and to flow around the conveyor rollers, and by second nozzles which direct second jets of cooling air upwardly between the rollers. The first and and second jets of cooling air produce respective first and second velocity profiles, each having an average velocity. The arrangement of the first and second nozzles in relation to each other and to the conveyor rollers is such that the velocity profiles of the first and second jets are superimposed one over the other to produce a broader combined velocity profile having an average velocity greater than that of either the first or second velocity profiles.

Abstract: A rotary kiln has a sealable separating gap between the kiln outlet head and an inlet shaft leading to a cooler. In order that the shortest possible drop height for the fired material falling out of the discharge end of the rotating cylinder may be maintained despite the separating gap, interengaging steps and side openings defined thereby are formed in the side walls of the kiln outlet head and the inlet shaft, and sections of the separating gap which run at different heights open into the side openings and the horizontal distance between any two steps lying opposite one another corresponds approximately to the maximum displacement path of the kiln outlet head.

Abstract: The invention relates to an inlet for a cooler in a rotary furnace. The lining of the inlet opening comprises a frame structure masoned of prefabricated lining blocks and a similarly prefabricated central part. The central part comprises a steel mould, a lining cast in the mould, and preferably also a transverse beam of steel. The central part is removably mounted in the steel jacket of the cooler inlet. The object of the invention is, on one hand, to permit a quick replacement of a worn lining of the cooler inlet and, on the other hand, to improve the quality of the lining because this can always be cast under controlled conditions.

Abstract: The cast metal grill element, which is the subject of this invention, concerns an apparatus for heat exchange between a solid in the divided condition, at high temperature, and a fluid, and comprises a plate of refractory steel, which is apertured with holes therethrough and the upper face of which comprises at least one recessed region, in the bottom of which is a hole in which the leg of a connecting member is engaged, the connecting member securing the grill element to its support. The grill element is for use in particular in cement works, in an apparatus for heat exchange between clinker and air.

Abstract: A calcining system wherein raw material is preheated by raw material preheating device for preheating the raw material by contact with a gas, calcined in a rotary kiln and cooled in a planetary cooler; a portion of cooling gas used for cooling the calcined material in the planetary cooler and heated thereby is led through an air extracting duct to the raw material preheating device and the rest of the heated cooling gas is introduced into the rotary kiln: and exhaust gases from the rotary kiln is led to the raw material preheating device.

Abstract: A cooler grate for hot cement clinker is provided with a plurality of rows of air holes and the bottom face of the grate is formed with a plurality of fins which undulate between the successive air holes to impart strength to the grate and turbulence to the air directed upwardly through the grate so as to cool the grate to a temperature substantially below the hot clinker on the grate.

Abstract: A calcining system for the manufacture of cement clinker and the like including the combination of a preheater into which the raw material to be calcined is introduced, a rotary kiln which receives the preheated material either directly or through a preliminary calcinator, and a cooler which receives the discharge of the rotary kiln. In accordance with the invention, a heater means is operatively associated directly with the cooler to bring the cooler up to operating temperatures during start-up.

Abstract: A planetary cooler has a plurality of circumferentially spaced cooling tube supports each of whichhas a pair of axially spaced side plates and an insert with two flanges which are fitted into openings in the side plates and welded to the latter. Each flange has a pyriform opening which communicates with a radial clearance extending between circumferentially adjacent side plates at their radially outer portions.

Abstract: A rotary kiln having a plurality of outlets for passage of material from within the kiln to associated cooler tubes mounted in use in planetary fashion around the outlet end of the kiln. Each kiln outlet has a tubular support to which the inlet end of the associated cooler tube is attached, and a steel reinforcing ring within the support. Insulation is provided between the ring and the support and the ring is lined internally with a wear-resisting ceramic material. An annular collar is formed of the same material as the ring and extends radially beyond the joint between the support and the kiln shell. The collar--which is bolted to the kiln shell--is insulated from both the support and the kiln shell and is coated with a wear-resistant ceramic material.

Abstract: In a process and plant for producing cool sintered particulate agglomerated solids of ore, the solids are moved in a continuous stream through a heat-treating zone to form a layer of the agglomerated solids and hot particles thereof are obtained from the layer. The hot particles are moved in a continuous stream into a structurally separate cooler which is heat-insulated from the heat-treating zone and through the cooler in a cooling path. Cooling air is blown into the cooler to flow countercurrently to the continuous stream of hot particles in the cooling path to subject the hot particles to forced countercurrent cooling whereby the cooling air is heated by contact with the hot particles and the entire heated cooling air is delivered into the heat-treating zone.

Abstract: A method for processing various organic materials such as lignocellulosics or biomass into more useful states, such as charcoal, carbon black, and coke, and other processed products while producing useful off-gases, includes feeding aggregate pieces of the material to a vertically extending heating chamber and, preferably, closing the chamber to air to control oxygen therein. The pieces are conveyed upwardly through the chamber in a predetermined time by spiral vibratory conveyor. The chamber is heated to a preselected temperature sufficient for gaseous conversion of volatile hydrocarbon constituents of the material. Resultant off-gases are removed from the chamber for further use such as burning thereof for heating the chamber or condensing volatiles, etc.Apparatus for carrying out the method includes preferably first and second such chambers, there being continuous spiral vibrator tray in each chamber carried by a central, vertical support column.

Abstract: A rotary kiln (1) having a plurality of cooler tubes (2) arranged in a planetary fashion therearound. The cooler tubes (2) rest in saddles in a ring-shaped member (3) surrounding the rotary kiln and are retained in the saddles by caps (4) with clearance so as to permit axial movement and radial heat expansion of the cooler tubes (2). The ring-shaped member (3) is attached to the kiln (1) by a plurality of ring support members having a first flange (6) attached to inner surface portions of the ring-shaped member, a second flange (5) attached to outer surface portions of the kiln (1) and an intermediate web member (7) having a substantially frusto-conical surface and connecting the first flange (6) and the second flange (5). Preferably, the first flange (6) and web member (7) have slots (8) extending axially of the kiln across their entire lengths. The slots (8) can extend axially of the kiln across the second flange (5) as well.

Abstract: Rotary drum type heat treatment apparatus having a rotary drum rotatable about a longitudinal axis. The drum has an outlet end and the apparatus includes a cooling section having a movable grate with one end disposed beneath the outlet end of the rotary drum for receiving material from the drum. The drum is provided at the outlet end with a plurality of circumferentially spaced distribution members, each of which has at least one side surface extending longitudinally outwardly beyond the outlet end and inclined with respect to a radial line of the drum for engagement with material being discharged through the outlet end to deflect the same.

Abstract: Individual suspension of satellite cooling tubes with the aid of wire cables in the region of the discharge end of a revolving tubular kiln in two support locations spaced apart on the axial direction. Each suspension unit comprises a number of suspension elements selectable according to the operative requirements. These elements preferably include three pretensioned wire cables anchored to suitable retaining elements secured to the kiln casing. In a preferred embodiment, the wire cables are arranged so that two of them exert upon the associated cooling tube a tractive force, the resultant of which is oriented towards the kiln axis, whereas the third wire cable, which is anchored by at least one resilient element, applies to the cooling tube a force directed in opposition to the resultant and of equal value.

Abstract: Satellite cooling tubes are mounted about a cylindrical rotary kiln, and funnel-shaped couplings connect one end of each cooling tube to the cylindrical kiln. A pair of cylindrical discharge spouts and connecting sockets are connected between the kiln and each of the funnel shaped couplings. The discharge spouts are arranged in an equally spaced annular array about the rotary kiln in two annular rows with the spouts of one row being offset circumferentially with respect to the spouts of the other row.

Abstract: The invention has to do with an apparatus for removing heat from cylinders of the rotary kiln recuperator cooler. The apparatus comprises heat-exchange tubes which are fixed on the lateral surfaces of bow-shaped support members so that they go around the cooler surface along a wave line with a space of variable cross section being formed between the heat-exchange tubes and the surfaces of the cylinders. Such constructional arrangement of the apparatus permits the heat-transfer area to be increased and substantially greater amount of heat to be removed from the surfaces of the cylinders.

Abstract: The invention relates to a method to promote the physical or chemical exchanges in a moving mass of material contained in a rotating exchanger. A gaseous or liquid fluid which may be combustible or not, is forced through the said mass in movement by injecting the said fluid within the said moving material by means of a system of variable flow injectors passing through the wall of the rotating exchanger.

Abstract: A rotary kiln has at one end circumferentially spaced apart outlet openings into each of which extends a sleeve establishing communication between the interior of the kiln and a planetary cooling tube. Encircling the inner end of each sleeve is a refractory collar that is flush with the surface of the kiln's lining. Between each tube and the edge of the associated outlet is a thermally insulative packing.

Abstract: An improved apparatus for cooling heated metal items such as extrusion billets, and in particular billets of aluminum alloys is disclosed. The apparatus comprises a cooling chamber, means for transporting individual billets into and out of the cooling chamber, and inlet and outlet openings for the ingress and egress of a cooling medium from said chamber. A fan or the like is employed to produce a flow of air through the cooling chamber.

Abstract: A cementitious product is produced from a combination of two groups of materials: the first group consisting of lime or Portland cement or Linfan (which is defined as a thermally cracked shell of calcium sulfate surrounding a core of lime) or Linvein (a lime particle coated with cracked calcium carbonate); and a second material consisting of thermally cracked fly ash which is cracked by thermally quenching such finally divided particulate material from an elevated temperature at least above 300.degree. C. and preferably higher than 450.degree. C. to ambient or below ambient temperatures.The two materials are blended together. They are mixed with water, placed in a form, and then allowed to cure. Filler materials can also be used in the form of sand, gravel, and other aggregates, depending upon the strength and compositional characteristics desired in the final product.