Abstract: This invention relates to a method and an apparatus for heat treatment of a powder material comprising a device for post-combustion of the combustible constituent remaining in the powder material which contains, or is mixed with, a constituent apt to cause an exothermic reaction either with a gas or with another constituent, proceeding from a precalciner ensuring a primary combustion of the said constituent, so as to achieve the complete combustion of the said constituent.

Abstract: Pulverized mineral material is calcined by suspending it in a current of gas constituted by a combustive gas and a fuel whose combustion furnishes the necessary calories for the calcination. To enable solid fuels rich in ash, substantially inert and difficult to condition to be used, the fuel is gasified in a fluidized bed hearth by blowing air from below through the bed whereby a gaseous fuel is disengaged from the bed and flows upwardly with the very finest particles of the solid fuel suspended therein. This is mixed with air and the mineral material to calcine the same.

Abstract: A method and apparatus for the removal of hazardous and waste materials of low heat content, for example, refuse, by means of combustion wherein the combustion process is carried out in a furnace by the presence of added hot combustion air at a temperature sufficient so that the combustion and/or flue gas temperatures are at least 1250.degree. C. In a preferred embodiment of the invention, the combustion process is combined with a process for the production of cement clinker and carried out parallel to the same, wherein air at about 800.degree. C. is branched off for combustion of the hazardous substances from the cooler air of the cement clinker installation and introduced into the furnace. The hot flue gas of the combustion in the furnace is directed into the cement clinker installation. The invention further contemplates that calcium-containing carbonate carriers can be added to the refuse.

Abstract: An improved process and apparatus for producing sintered material such as dead burned clay, dolomite, magnesite or periclase with the highest particle specific gravity capable from each material. A grinding mill produces raw material which is 100% minus 20 mesh. The ground raw material is supplied to a suspension type preheater and then to a stationary flash calcining system where the material is soft burned at temperatures in the range of 1000.degree. to 1200.degree. C. From the calcining system, the calcined material is immediately supplied to hot briquetting machine where briquettes or nodules are formed. The hot nodules at a temperature of approximately 800.degree. C. are then immediately supplied to a rotary kiln which serves as a sintering furnace where the soft burned material is dead burnt at a temperature in the range of 1650.degree. to 1850.degree. C. Hot spent combustion gas from the sintering furnace is supplied to the calcining furnace to serve as preheated secondary air for combustion.

Abstract: There is here disclosed a calcining apparatus for a powdery material comprising a first preheating series composed of a calcining kiln and preheaters at a plurality of stages for heating the powdery material with an exhaust gas from the calcining kiln, a second preheating series composed of a calcining chamber disposed on an exhaust gas pipe extending from a rotary kiln and other preheaters at a plurality of stages for heating the powdery material with an exhaust gas from a rotary kiln, a gas carrying pipe for connecting the first and second preheating series in the middle thereof, and a flow path through which the powdery material fed to first and second preheating series passes is provided with a powdery material carrying pipe for connecting both series in front of second preheaters from the bottom in both series, and is further provided with a combining duct for combining powdery materials from both the series in the rear of the second preheaters from the bottom in both series, the flow path for the powder

Abstract: A method for the thermal treatment of mineral raw materials containing calcium carbonate and similar carbonates, particularly for the production of calcined products such as burnt lime, cement, magnesite, dolomite or the like wherein the raw material carriers of the calcium or other carbonate constituents are supplied to the calcining unit with a particle size of from 1 mm to 25 mm. The calcareous constituents are preferably supplied to the calcining unit with a particle size from 1 mm to 4 mm. To achieve this condition, the raw material containing the calcareous constituents is preferably pre-crushed to a particle size below 200 mm and pre-homogenized. It is then supplied to a drying comminution system connected to the calcining unit at the gas side and is suspended therein in direct heat exchange relationship with the gases. The material is preferably processed by means of single-stage crushing and grading to form the appropriate particle size.

Abstract: A method and apparatus for the heat treatment of fine-grained material wherein the degree of efficiency of the last cyclone of a multi-cyclone preheater preceding a filter is reduced in the finest grain size range and at least a proportion of the filter dust deposited in the filter is passed directly to the calciner. In this way material is prevented from caking and flowing in batches in the apparatus.

Abstract: Pulverized mineral material is calcined by suspending it in a current of gas constituted by a combustive gas and a fuel whose combustion furnishes the necessary calories for the calcination. To enable solid fuels rich in ash, substantially inert and difficult to condition to be used, the fuel is gasified in a fluidized bed hearth by blowing air from below through the bed whereby a gaseous fuel is disengaged from the bed and flows upwardly with the very finest particles of the solid fuel suspended therein. This is mixed with air and the mineral material to calcine the same.

Abstract: A combination direct/indirect fire drum heating and mixing apparatus includes a frame having an inner cylindrical drum rotatably supported thereto and having an aggregate input in one end thereof and an aggregate output at the other end thereof. A concentric outer drum is mounted around the inner drum and has an aggregate input from the material output of the inner drum and an aggregate output therefrom at the other end thereof, so that aggregate materials can pass through the inner drum and then pass between the inner and outer drums. A burner is mounted to one end of the inner cylindrical drum for directing a flame thereinto and includes a burner blower for blowing atmospheric air under pressure into the burner. An exhaust gas outlet duct operatively connects the exhaust gas from the inner cylindrical drum to the atmosphere or particulate-removing apparatus, while an exhaust gas feedback siphons vapors and gases emitted in the space between the two drums for incineration through the system burner.

Abstract: An apparatus for preheating granular ore includes a shaft defined by vertical walls, an inlet chute disposed above the shaft for introducing the ore thereinto by gravity, an ore discharge collector situated underneath the shaft for receiving preheated ore therefrom, and an arrangement for passing heating gases upwardly in the shaft. The discharge collector has vertical side walls and further, there is provided an insert situated in the discharge collector and extending generally horizontally thereacross. The insert has a downwardly widening configuration. A discharge device is disposed at a lower end of the discharge collector.

Abstract: A method and apparatus is disclosed for combustion of diverse materials, particularly combustible solids, liquids or gases, such as sewage sludge, refuse, coal, refinery sludge, tar sands, coal shale, coal tailings and spent foundry sand. A rotary combustion apparatus is employed which consists of a cylindrical drum, or other similar regularly shaped chamber, with a substantially horizontal axis of rotation including an ignition zone, a principal combustion zone, a falling temperature zone and a spent solids removal zone. The apparatus further includes solids transport chutes for forward and backward circulation of solids, arranged for the transfer of solids to or from one or more points. Feedstock may also be heated by recycled hot solids. The method and apparatus employs direct solids-to-gas contact established by lifting and cascading combustible solids through a hot gas stream.

Abstract: A process for the calcination of a solid pulverulent material comprises the steps of gasifying a solid fuel in a fluidized bed to produce an ascending current of gaseous fuel, and injecting the material in an oxidizing carrier gas into the ascending gaseous fuel current above the fluidized bed of solid fuel to disperse the pulverulent material in the gaseous fuel current, the flow velocity of the gases in the zone of injection of the material into the current being sufficient to entrain the material in the gases and to prevent them from falling into the fluidized bed.

Abstract: The invention relates to a method and apparatus for the heat treatment of fine-grained material wherein a precalcination zone formed by the kiln exhaust gas duct of a rotary kiln and into which two branch streams of cooling air which have been subjected to opposing rotational flow are introduced. In this way an equalization of the speed profile over the cross-section of the kiln exhaust gas duct and an improvement in the burning up of the fuel is achieved.

Abstract: A rotary kiln for roasting cement raw meals provided with, on the raw meal inlet side of the kiln, a suspension preheater having a calcining furnace, which includes a kiln body lined with refractory materials, a mechanism for supporting said kiln body with a slight inclination to the horizontal, and a mechanism for rotating the change kiln body around an axis thereof and on the supporting mechanism at a variable speed, wherein the slope of the axis of the kiln body ranges from 1.5% to 3.5% and the maximum rotational speed of said kiln body is in a range represented by the following equation: N=(0.2.about.0.4).times.42.3/.sqroot.D wherein N is the maximum rotational speed of the kiln body, and D is the inside diameter of refractory materials in the granulating zone of the kiln, thereby improving the granulation of the cement raw meals in the kiln.

Abstract: A method of producing cement from raw material containing a harmful substance such as sulphur, alkali and/or chlorine. In order to reduce the circulation of harmful substances a proportion of the gas or material stream is extracted from a zone in the cyclone preheater at which the desired reduction in the content of the harmful substance is achieved with minimum heat loss.

Abstract: A dust preheating system with an incipient calcinating furnace for powdery material, including a combustion furnace, a clinker cooler located on a downstream side of the combustion furnace, a preheater having a plurality of dust separators connected in series in a vertical direction to form a corresponding number of preheating stages, an incipient calcination furnace located between said preheater and said combustion furnace when seen in a flow direction of said powdery material and connected through a combustion air duct to the clinker cooler, the incipient calcination furnace including an independent fuel feeder and connected through a combustion gas duct to a lowermost dust separator of the plurality of dust separators for calcined material, a second lowest dust separator of the preheater having a dust outlet thereof connected to the incipent calcination furnace, and the lowermost dust separator having a calcined dust outlet connected to an inlet of the combustion furnace, wherein the second lowest dust se

Abstract: A method and apparatus is disclosed for retorting particulate solid materials, particularly hydrocarbon-containing materials such as oil shale, oil sands, tar sands, coal shale, coal tailings, and the like, for the recovery of a volatile constituent such as oil or gas. A rotary retorting apparatus is employed which consists of a cylindrical drum, or other similar regularly shaped chamber, with a substantially horizontal axis of rotation and having multiple compartments for retorting and combustion and, optionally, spent solids cooling. The apparatus further includes solids transport chutes for forward and backward circulation of solids, arranged for the intercompartmental transfer of solids with the capability of additions at one or more points in each compartment. Employing the method and apparatus, particulate solids feedstock is heated by recycled spent solids material to remove the volatile constituent of the feedstock in the retort section.

Abstract: An apparatus for burning pulverulent raw material, in particular cement raw meal to cement clinker, has a kiln (1), a cooler (2), a suspension calciner (4-12) and a multi-stage preheater (14-27). The preheater is provided with two material outlet ducts (22 and 22') directing a first stream of preheated material to a suspension burning chamber (4) with a hot air inlet (7) and a fuel inlet (5) and a second stream of preheated material to a kiln gas duct (28), respectively. Rapid quenching of kiln gas and accelerated rate of combustion in suspension calciner are provided by suspending and calcining the material in the streams in the burning chamber and the kiln gas duct, respectively, and uniting the two suspensions downstream of the suspension burning chamber (4). The calcined material is precipitated in and passed to the kiln from a precipitator (9), to which the united suspensions are directed.

Abstract: A method and an apparatus for calcining pulverulent raw material, in particular cement raw meal, wherein the material is calcined suspended in a stream of hot gas in a calcining zone (4) in an overheated atmosphere by burning fuel in a stream of oxygen-containing gas in the zone, and precipitated in a precipitation zone (9). The rate of combustion of the fuel is accelerated by maintaining a temperature within the range 900.degree.-1250.degree. C. in the calcining zone by dividing the raw material into two streams (22',22) introducing and calcining only the first stream of material (22') in the calcination chamber (4). The temperature of the hot suspension withdrawn from the calcining zone is reduced by 100.degree.-300.degree. C. to a level within the range 800.degree.-1000.degree. C. by suspending the second stream of material (22) in the hot suspension during withdrawal thereof from the calcination chamber (4) and before the calcined material is precipitated in the precipitator (9).

Abstract: An improved process for recycling asphaltic concrete comprises introducing asphaltic concrete particles at one end of an elongated rotating drum while supplying flame and hot gases of combustion to the drum at the opposite end, and introducing virgin aggregate into the drum intermediate the two ends. The asphaltic concrete is heated as it travels along a portion of the length of the drum and is recovered just prior to reaching the position along the drum length at which the aggregate is introduced. The aggregate is heated as it travels toward the end of the drum at which the flame and hot gases are introduced. Heated aggregate may be returned to the drum for further heating, and may be directed to the opposite drum end and mixed with the asphaltic concrete in a section of the drum.

Abstract: There is here disclosed a calcining apparatus for a powdery material comprising a first preheating series composed of a calcining kiln and preheaters at a plurality of stages for heating the powdery material with an exhaust gas from the calcining kiln, a second preheating series composed of other preheaters at a plurality of stages for heating the powdery material with an exhaust gas from a rotary kiln, and a gas carrying pipe for connecting the first and second preheating series in the middle thereof, a flow path for the powdery material being adapted so that the powdery material fed to each series may be led into the rotary kiln via a combining duct disposed in front of the undermost preheaters in both the series and then via the undermost portions of both the series. Further, disclosed is a calcining apparatus for a powdery material in which a sub-calcining kiln and a calcining chamber are disposed on an exhaust gas pipe extending from a rotary kiln.

Abstract: Apparatus and method for incinerating toxic and non-toxic waste using a modified preheater-type lime kiln is disclosed wherein the kiln is modified to incinerate waste and the preheater section is modified to provide an incineration processing aid such as limestone and also to more efficiently utilize and conserve heat values.

Abstract: Method and apparatus for burning fine grained material, particularly for the manufacture of cement clinker whereby the product quality is enhanced. At least a portion of the exhaust gases from the kiln at a temperature of about 1000.degree. to 1300.degree. C. are cooled by passing them through a steam generator to a temperature of about 200.degree. to 300.degree. C. At least a portion of the noxious substances such as alkali chlorides and sulfur are condensed out of the gas stream as well as possibly some mineral particles such as partially deacidified kiln dust. The materials condensed out of the gas are separated in the steam generator by means of periodic or continuous cleaning of the heating surfaces of the steam generator. The steam which is generated in the generator is conducted to at least one prime mover such as a steam turbine or a steam motor for the purpose of producing electrical or mechanical energy.

Abstract: An apparatus for the calcination of fine grained material, particularly material used to produce cement clinker employing at least two separate, essentially parallel preheater lines, one of which is treated with exhaust gases from a clinker-forming zone and the other is equipped with a calcination zone which itself is fed by hot combustion air from the clinker cooler. In the area of the preheater line which is attached to the exhaust gas conduit of the clinker-forming zone, a divider device is arranged for dividing the stream of material. A first conduit directs a portion of the material into the exhaust gas conduit of the clinker-forming zone and a second conduit directs material into the calcination zone. The calcination zone is in the form of a vertical reaction duct having a downwardly bent pipe at its upper end. There is also provided a conduit which connects the vertical reaction duct with the exhaust means for hot gases in the clinker-forming zone.

Abstract: A precalciner for cement raw meal is divided into upper and lower parts. The upper part is shaped into a cylinder, while the lower part is constituted by upper and lower inverted conical portions. The upper inverted concial portion has a cone angle smaller than that of the lower inverted conical portion and is connected to the lower end of the upper part through a throttle device.

Abstract: An installation for the thermal treatment of a pulverulent mineral product by gases has a support frame at a first level, a furnace for the thermal treatment of the pulverulent mineral product in suspension in hot gases generated by the combustion of air and a fuel, two groups of series-connected cyclones connected to the furnace, one of the groups of cyclones being arranged upstream of the furnace and the other group of cyclones being arranged downstream of the furnace, and conduits connecting the cyclones to each other and to the furnace so that exhaust gases from the furnace pass successively through all the cyclones of the one group while a current of air passes through all the cyclones of the other group before entering the furnace to serve as the combustion air, the exhaust gases heating the product before it enters the furnace and the air current cooling the treated product.

Abstract: Apparatus for heat treating fine-grained material comprises a rotary kiln into which material is delivered from a multistage preheater that communicates with the kiln via a vertical exhaust gas duct. Treated material is discharged from the kiln to a cooler from which two cooling air ducts extend and communicate with the exhaust gas duct at two vertically spaced zones. Material from the second lowest preheater stage is introduced into the exhaust gas duct adjacent the lower cooling air duct. Fuel is introduced into the exhaust gas duct adjacent each of the cooling air ducts. The apparatus is distinguished by a particularly high degree of deacidification of the raw material and good combustion of the fuel.

Abstract: A mechanism and method for calcining cement including a precalciner and a rotary tubular kiln receiving material therefrom and discharging through a vertical conduit to a cooler, means for delivering air through the cooler to flow up through the conduit to the kiln with a laterally movable plate type valve controllably positioned in the shaft to increase the resistance to gas flow from the cooler to the kiln and a branch conduit for receiving excess air from the cooler as tertiary air and delivering the air to the precalciner with means for separating a dust from the tertiary air.

Abstract: The present invention deals with a chute for a kiln intake housing of a rotary tubular kiln or the like, the chute having a lining composed of a refractory material and a double-walled, inwardly facing collar disposed at the lower end thereof, the collar functioning to support the lower end of the refractory lining within its metal jacket and the collar being equipped with a special coolant circulating device. The inner end of the collar is composed of support segments which are connected to each other and to a holding means, the interior space of the collar being subdivided as required in order to provide for an induced circulation of a coolant.

Abstract: An apparatus (14) embodying heat exchange means for treating solid, granular and aggregate materials, and in particular for treating spent, i.e., used, chemically bonded foundry sand. The subject apparatus (14) includes a rotatable first chamber means (16) in which the used foundry sand is preheated while traveling in a first direction therethrough from one end thereof to the other end thereof. From the first chamber means (16) the preheated used foundry sand is suitably conveyed to a thermal reclaimer means (12) for purposes of thermally removing organic matter therefrom. Thereafter, the used foundry sand is conveyed to a second chamber means (44) wherein the used foundry sand undergoes post reclamation whereby any organic matter that may yet remain in the foundry sand is thermally removed therefrom. From the second chamber means (44) the used foundry is made to pass into a third chamber means (52) which is located in surrounding heat exchange relation to the first chamber means (16).

Abstract: A method and apparatus for burning fine grained products, such as in the manufacture of cement clinker from raw cement meal wherein preheated, calcined meal is heated in a separate heating assembly to a temperature from approximately 900.degree. C. to approximately 1250.degree. C. and is then sintered into clinker in a burning assembly such as a rotary tubular kiln. The present invention provides a means for achieving a fast and uniform continuous heating in the heating assembly without reaching the critical temperature of melt phase formation and without danger of encrustations, the heat required for rapid heating being released in controlled amounts in the heating assembly, where it is immediately absorbed by the product, the heat being provided by a plurality of points of fuel introduction and/or combustion air introduction distributed over the heating assembly.

Abstract: A method and apparatus for burning cement clinker from differing mineral base materials. One of the base materials has a relatively high proportion of components which form melt phases at a predetermined temperature and another base material has a relatively slight proportion of such components. The two base materials are separately thermally pretreated. The base material higher in melt phases is at least partially melted after thermal pretreatment and is introduced into a clinker reactor in its molten state together with the thermally pretreated base material which is lower in melt phases and still exists in the solid phase. The mixture is heat treated and finish-burned into clinker in the clinker reactor. The invention also comprehends apparatus for performing the method of the invention.

Abstract: A method for removing fine-grained sediments from flowing or standing bodies of water. The sediment is dredged from the bottom of the body of water. The dredged sediment is dewatered and classified in a sieve plant. At least a fine-grained admixture material such as fly ash or refined clay is admixed to the dewatered sediment material. The admixture is granulated and the resulting granulate is dried and fired under swelling. The swelled, fired granulate is cooled and further processed. The light weight granulate is admixed to concrete or used in the production of building materials such as sinter blocks and bricks. The noxious materials and heavy metals contained in the sediment are substantially sealed into the granules produced by sintering. The resulting waste waters can be cleared such that they are suitable for feeding back into the bodies of water. The residues of the waste water treatment can also be employed as admixture component in the granulate production.

Abstract: In a primary air supply unit of a rotary kiln, an improved method for reducing a primary air rate by providing a high-pressure blower for primary air to inject the primary air from a burner together with fuel. In addition, in order to preheat the primary air and to protect any fragile portions in a clinker box for cooling sintered material from the rotary kiln and for preheating the primary air.

Abstract: A method and apparatus for burning fine grained products, such as raw cement meal, wherein the product is preheated in a preheating stage, calcined in a calcining stage, and is burned into clinker in a clinker stage followed by cooling in a cooling stage. The heating of the largely calcined product in the temperature range of about 900.degree. C. to the beginning of alite formation which occurs at approximately 1250.degree. C. is carried out under the fastest possible temperature rise conditions and the clinker reaction is carried out in concurrent flow with the gas stream in the burning stage. The clinker is then graded into a coarse grained fraction and a fine grained fraction which are then cooled in separate coolers after separation from the gas stream.

Abstract: A method of calcining mineral components such as bituminous limestone in which heat is recovered from the calcining process and is used to liberate volatilizable substances within the mineral matter before the latter is subjected to calcination. The volatilized and pyrolytically decomposed substances form a fuel which is burned to produce the calcining gas mixture.

Abstract: A method and apparatus for producing expanded clay or expanded shale finished product in a straight-line continuous rotary tube kiln provided with charging and discharge ends at respectively opposite ends of the kiln, the kiln being divided into a preheating zone and an expansion zone following one another in the direction from the charging end to the discharge end, the preheating zone being more proximate to the charging end and the expansion zone being more proximate to the discharge end, a stationary burner disposed in the vicinity of the discharge end and a mantle burner which rotates together with the kiln and which is located to heat the preheating zone.

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: Fine-grained material such as raw cement meal is preheated in a multi-stage cyclone preheater, precalcined in a precalcination zone, sintered in a rotary kiln, and cooled in a cooler. Exhaust gases from the kiln are delivered to the precalcining zone and then to the preheater. Tertiary air from the cooler is divided into two streams one of which is mixed with kiln exhaust gases between the kiln and the precalciner and the other of which is delivered directly to the precalciner. The quantity of tertiary air flowing through each branch is regulated to maintain the temperature of the kiln exhaust gases at a selected value.

Abstract: Apparatus for heat treatment of fine-grained material has a multi-stage cyclone preheater, a rotary kiln, and a gas pipe extending between the kiln and the preheater and forming a calcination zone for precalcining materials entrained in the gas stream. The gas pipe has an upwardly extending pipe section that communicates with an arcuate deflector section and a downward pipe section which extends downwards to and communicates with the lowest cyclone stage. The downwardly extending pipe section of the gas pipe has an extension constructed as a coarse separator so that relatively coarse material particles contained in the mixed gas-material stream are kept away from the lowest cyclone stage of the preheater.

Abstract: A process for the calcination of a solid pulverulent material comprises the steps of gasifying a solid fuel in a fluidized bed to produce an ascending current of gaseous fuel, and injecting the material in an oxidizing carrier gas into the ascending gaseous fuel current above the fluidized bed of solid fuel to disperse the pulverulent material in the gaseous fuel current, the flow velocity of the gases in the zone of injection of the material into the current being sufficient to entrain the material in the gases and to prevent them from falling into the fluidized bed. An apparatus for the calcination comprises a calcination chamber whose bottom is a grid carrying a bed of solid fuel through which air is blown to produce the ascending current of gaseous fuel in the chamber. An array of nozzles in an upper portion of the chamber is used to inject the pulverulent material suspended in the carrier gas into the chamber above the fluidized bed.

Abstract: A method of and apparatus for recovering exhaust gas from a boiler 2 of a thermal electric power generating device 1 are disclosed. The exhaust gas from the boiler 2 is fed through a conduit 30 to a preheat section 21 of a powder raw material treating device 20. The heat of the exhaust gas is recovered as a heat source for preheating the powder raw material. The ash contained in the exhaust gas is recovered as part of the powder raw material at the preheat section. The sulfur oxides in the exhaust gas react with the desulfurizing component of the powder raw material at the preheat section, and its reaction product is recovered as part of the powder raw material.

Abstract: A method and mechanism for heat treating a pulverulent comminuted raw material in the process of making cement including preheating the material, passing the material through a first reaction zone, supplying a first fuel supply to the first zone for supplying thermal energy for carrying out the calcination reaction, separating the material from the hot gases received from the first reaction zone and delivering the material to a second reaction zone to which is supplied a second fuel supply for supplying thermal energy for the calcination reaction in the second zone and separating the material from the hot gases from the second zone and delivering the material to a sintering kiln and then passing it to a cooler with the air from the cooler supplied to support combustion in the first zone, and with the arrangement preferably arranged in two parallel flows with each flow path containing the preheater, and the reaction zones and separators with the material flows combining just as they enter the sintering zone.

Abstract: A system including a method and apparatus for incinerating toxic and non-toxic waste materials. The system involves the use of a pre-treatment agent which is capable of insuring flowability in the waste materials to be incinerated. The agent is mixed with the material and then introduced to a rotary kiln which is fired to a temperature such that incineration of the material will occur by providing a satisfactory rate of material flow through the kiln. The kiln includes a rotary scoop feeder which is utilized for introducing the mixture of material and agent into a hot zone of the kiln. An afterburner may be utilized for decomposing materials such as hazardous organic wastes, and the output of the apparatus may be associated with a baghouse.

Abstract: To permit the utilization of high-sulfur content solid fuels in the production of cement clinker in rotary kilns, the solid fuel is gasified and the gasified fuel is contacted with a fraction of the raw material used for the production of the cement clinker to desulfurize the gasified fuel, the desulfurized gasified fuel being delivered to a calcination stage and/or the rotary kiln for furnishing calories thereto.

Abstract: The invention relates to apparatus for introducing fine material into a combustion zone by means of an air duct which has a constriction in the region of its junction with the material duct in such a way that the rate of flow is considerably increased at the point where the material is introduced and this favors the loosening of the material stream and the delivery of the material to the combustion zone.

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: This disclosure relates to a rotary kiln for heating and calcining lime, waste, etc. and to a method of direct reduction of metal oxide using such a kiln. A cylindrical outer shell is mounted for rotation on its axis, and a stationary inner tube extends into the interior of the shell. Fuel and/or combustion air flow passages extend within the tube, and burner nozzles are supported by the tube and are connected to the passages. The tube is concentrically or eccentrically mounted adjacent the upper side of the space within the shell, thereby positioning the burner nozzles at the optimum positions.

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 coke calcining apparatus comprises a rotary kiln (1), an intermediate cooler (3) installed outside of but rotating unitarily with the kiln at an intermediate part thereof and having inlets (32) and outlets (33) respectively communicating with the upstream and downstream interiors (A,B) of the kiln, and an annular weir (7) fixed to and around the inner wall surface of the kiln at a part thereof between the inlets and outlets of the cooler and functioning to cause the entire quantity of coke (6) which has been subjected to a first-stage calcination at 600.degree. to 1,000.degree. C. in the upstream interior (A) to flow through the cooler (3). The coke thus cooled to 200.degree. C. or lower is subjected to a second-stage calcination at 1,200.degree. to 1,400.degree. C. in the downstream interior (B) for 10 to 30 minutes.