Abstract: A limestone preheater which segregates material according to particle size and further provides for material bed depth adjustment, preferably during operation.

Abstract: A process for decarbonation of particles of raw meal, to be burnt in a clinkering kiln at a cement plant, the process includes: a) decarbonation of particles of raw meal, in a fluidised bed heat exchanger, the particles being suspended in a rising carrier gas including carbon dioxide, the fluidised bed heat exchanger having a solid heat carrier circulating counter-current relative to the carrier gas, to provide an effluent gas including carbon dioxide and decarbonated raw meal; b) separating the effluent gas and the decarbonated raw meal c) separating the effluent gas into a first and second part; cooling the first part of the effluent gas and recycling to provide carrier gas, d) isolating the second part of effluent gas e) recovering and re-heating the heat carrier and recirculating to step (a).

Abstract: A preheating apparatus for particulate material using hot kiln gases to preheat the particular material. The apparatus has a means to cool the hot kiln gases prior to the gases being exhausted from the preheating apparatus.

Abstract: A loading device for a shaft furnace comprises a chute supported by a suspension rotor (28) in a fixed housing. The rotor (28) is fitted with a cooling circuit, supplied with liquid coolant via a rotating annular joint (44). The latter comprises a fixed ring (60) and a rotating ring (62), and is fitted in an annular leak collecting tank (46) formed by the suspension rotor (28). Fixed ring (60) is supported by the housing (12). Rotating ring (62) is supported entirely by fixed ring (60) via a bearing (64). Selective coupling means (65, 66) connect the rotating ring (62) to the suspension rotor (28) in such a way as to transmit a rotary moment of rotor (28) to rotating ring (62) selectively, while at the same time preventing other forces from rotor (28) being transmitted to rotating ring (62).

Abstract: An apparatus for melting materials is provided comprising a melter body having a batch injection portion including a batch inlet port, a batch melting portion including a batch melting chamber adapted to receive materials from said batch injection portion, and a molten materials delivery portion including a molten materials outlet port. At least one jet stream injection assembly injects a jet stream into said batch melting chamber. The jet stream comprises a fuel, an oxidant, and heated products of combustion and produces a vortex flow pattern in said batch melting chamber. Fuel and oxidant within said vortex flow pattern react to form laminar flamelets within said vortex flow pattern. The heat generated in the flamelets melts the materials.

Abstract: An apparatus for melting materials is provided comprising a melter body having a batch injection portion including a batch inlet port, a batch melting portion including a batch melting chamber adapted to receive materials from said batch injection portion, and a molten materials delivery portion including a molten materials outlet port. At least one jet stream injection assembly injects a jet stream into said batch melting chamber. The jet stream comprises a fuel, an oxidant, and heated products of combustion and produces a vortex flow pattern in said batch melting chamber. Fuel and oxidant within said vortex flow pattern react to form laminar flamelets within said vortex flow pattern. The heat generated in the flamelets melts the materials.

Abstract: This invention relates to a a vertical shaft kiln (VSK) useful for manufacturing cement and other allied products, which comprises a rotary nodule feeder for feeding the raw materials, fitted above the kiln bed for uniform distribution of nodules of the raw materials, an air blower being placed at the base of the kiln for feeding air through a duct to a common air header having a plurality of outlet air ducts, the air duct being connected to an air cone placed inside an armoured shell of the VSK, the said air cone being provided with a grate assembly having a plurality of peripheral air slots, the air duct being connected to an air box placed above the said armoured shell, the said air box having perforations on the inside vertical wall, the air duct being connected to an air header having air entry nozzles placed in such a manner so as to supply air just below the sintering zone of the VSK, the air duct being connected to the chimney of the VSK, the said chimney being provided with a butterfly valve below th

Abstract: Carbothermally reduce a metal oxide to its corresponding metal nitride or metal carbide powder in a vertical gravity flow reactor by adding precursor pellets containing the metal oxide, a thermally decomposed binder material and carbon or a source of carbon directly to a heated reaction zone within the reactor. The pellets form a pellet bed, the top of which must be maintained within the heated reaction zone. The binder material is a blend of wheat and corn starches, optionally in conjunction with another binder such as melamine. The binder material thermally decomposes to a carbonaceous residue which functions both as an additional source of carbon and as a binder for the precursor pellets. The reactor may be modified by adding an internal vent line to remove volatile materials from the heated reaction zone before they have an opportunity to condense on internal reactor surfaces.

Abstract: A circulating fluidized bed thermal reactor such as a boiler or gasifier, having the riser divided into a sequence of stages by a plurality of restrictions which create multiple beds dynamically suspended. Circulation occurs below transport velocity, solids distribution is substantially uniform, average bed density can be varied from near-zero to very high values, solids mobility is unrestricted, temperature is uniform. Gases follow multistage CSTR flow regime, specially suited for fuels which break down into volatiles upon heating, such as biomass, hazardous wastes and most fuels other than coal.

Abstract: An improved method preheating cullet and glass batch together for use as feedstock for a glass furnace. The method uses a preheater including a separator and a heat exchanger. The heat exchanger is a direct contact raining bed in which large particles in the feedstock are heated by hot gases as the particles flow down by gravity and fine particles become entrained with the hot gas flow. The separator removes the fine particles entrained in the hot gases and remixes preheated the fine particles with the preheated cullet. Preheater systems are described in which the hot gasses are provided by the glass furnace exhaust, by a separately fired heater, by a separately fired heater combined with the glass furnace exhaust and by a separately fired heater with exhaust gas recirculation.

Abstract: Process and furnace for producing clinkered cement pellets from pellets of cement-forming batch materials without melting, fusion and agglomeration of said pellets. The furnace comprises an elongate vertical suspension shaft having top, intermediate and bottom portions. Pellets are fed at the top and heated to calcining temperatures before exiting the shaft into a pre-clinkering zone beyond the bottom. The pellets are heated to pre-clinkering temperatures and deposited on a porous pellet bed through which cooling air is forced to control the exothermic clinkering reaction and to regulate the speed at which the pellets migrate through the shaft.

Abstract: Oven for dehydrating pulverulents, sand or granules, comprising an energy-saving dehydration device, adapted to gypsum burning. The device consists of an outer casing, an inner casing and flow cones disposed on said casings. A burner and a lock complete the device. Pressure within the oven is increased by the provision of a cover, a gypsum lock and a steam valve. The process takes place in dry or moist conditions, the latter being advantageous for the processing of insulating products or for gypsum amending the nature of plaster. Heat exchange enables the products to be processed at low temperatures. The central combustion chamber prevents loss by radiation. Application to gypsum burning, during which the device has demonstrated energy savings of 50% in comparison with traditional appliances.

Abstract: The apparatus herein comprises a kettle for calcining particulate material and a surrounding furnace having a porous wall to pass heat of combustion into the kettle at one side and to permit evacuation of the products of combustion from an opposite side, and a control system to cycle the combustion and the evacuation of products of combustion between the opposite sides so that the side being evacuated becomes a heat sink to return the heat so retained therein upon the combustion cycle whereby the furnace structure is kept to a desirable level of temperature while the material in the kettle is at a significant higher temperature.

Abstract: Process and furnace for producing clinkered cement pellets from pellets of cement-forming batch materials without melting, fusion and agglomeration of said pellets. The furnace comprises an elongate vertical suspension shaft having top, intermediate and bottom portions. Pellets are fed at the top and heated to calcining temperatures before exiting the shaft into a pre-clinkering zone beyond the bottom. The pellets are heated to pre-clinkering temperatures and deposited on a porous pellet bed through which cooling air is forced to control the exothermic clinkering reaction and to regulate the speed at which the pellets migrate through the shaft.

Abstract: A retorting apparatus including a vertical kiln and a plurality of tubes for delivering rock to the top of the kiln and removal of processed rock from the bottom of the kiln so that the rock descends through the kiln as a moving bed. Distributors are provided for delivering gas to the kiln to effect heating of the rock and to disturb the rock particles during their descent. The distributors are constructed and disposed to deliver gas uniformly to the kiln and to withstand and overcome adverse conditions resulting from heat and from the descending rock. The rock delivery tubes are geometrically sized, spaced and positioned so as to deliver the shale uniformly into the kiln and form symmetrically disposed generally vertical paths, or "rock chimneys", through the descending shale which offer least resistance to upward flow of gas. When retorting oil shale, a delineated collection chamber near the top of the kiln collects gas and entrained oil mist rising through the kiln.

Abstract: Oven for charring plant matter, downdraft intermittent operation type, without external energy source. The invention relates essentially to the arrangement of the hearth located at the bottom of the oven, which provides the mechanical stability of the whole, the distribution of fresh air by means of a device permitting the circulation of air on the inside, as well as the precise control of its admission and airtight sealing at the end of the cycle; the collection of gases and pyroligneous liquors by means of an annular collector terminating in a single flue. The pyroligneous liquors are collected at the bottom of the flue. A condenser maybe installed to recover tars or to provide complete processing of the gases. Removal of the charcoal by gravity through a central opening, the cover of which contains the closable lighting aperture.

Abstract: An improved charging process for an enclosure for melting materials such as blast furnace slags or basaltic glasses. The supply of combustive gas is carried out nonuniformly in order to create a gas circulation velocity gradient in the section of the cupola corresponding to the level of the tap hole, with the lowest circulation velocities meeting in the vicinity of the tap hole.

Abstract: A gas-solids heat/exchanger apparatus particularly designed for cooling the particulate material such as calcined limestone or cement clinker, but may also be used as a dryer and/or material heater. The apparatus includes a casing having an upper particulate material inlet and a lower particulate material outlet. Upper and lower grates extend on an angle or a slant from the inlet to the outlet for holding a bed of material. Gas is supplied to an inlet plenum chamber on one side of the lower grate for passage through the grates and the bed of material to an outlet plenum chamber. The lower grate is perforated to permit gas to pass therethrough while supporting the bed of material. The upper grate includes a plurality of spaced apart, vertically oriented, perforated slats. Various parameters or gas flow rates, pressure drops and positioning of the upper grate slats are disclosed.

Abstract: A regenerative shaft furnace for burning carbonate-containing raw materials is disclosed having two or more shafts which are interconnected by ducts which operate in an alternate manner and wherein the burned raw material is cooled in the cooling zone of the shafts. Having a displacer in the cooling zone to prevent the reabsorption of carbon dioxide in the fuel gases by the burned material. A method for burning carbonate-containing raw material is also disclosed.

Abstract: In a device for raising the temperature of a plurality of solids which utilizes a heating chamber having at least one hot flue gas inlet and one or more solids inlet apertures to supply concurrent flows of solids and hot flue gas to a heating chamber, and, which utilizes at least one disengager to deflect the heated solids and prevent the solids from being exhausted from the heating chamber along with the hot flue gas, means are provided for coaxially mounting at least one hot flue gas outlet downstream of and displaced from at least one of the solids inlet apertures. Additionally, an individual disengager is associated with each hot flue gas outlet, each disengager being coaxially aligned with and positioned intermediate its associated hot flue gas outlet and a corresponding solids inlet aperture. Each individual disengager is positioned within a direct flow path of solids from a single solids inlet aperture, to prevent thermal stressing of the individual disengager.

Abstract: The furnace is circular in plan and comprises an annular charge space charged through chutes in its top wall. Effluent gas offtakes are provided in the furnace outer wall and the level of the charge bed is maintained above the chute bottoms but below those offtakes. Hot gases generated externally of the furnace pass into it through an opening in its bottom wall or hearth and travel upwardly through the charge. Solids are discharged downwardly through the same opening in counterflow. A vertical axle is journalled centrally in an upper wall of the annular furnace chamber spaced above the opening in the hearth, and a plow affixed to the lower end of the axle rotates in an open space between the hearth of the annular furnace chamber and its inside wall, so scraping heated charge solids into the discharge opening. The axle is pressure sealed to the wall through which it passes, and that seal is the only rotating seal required for the furnace.

Abstract: Apparatus for contacting a packed bed of particulate material with a treating gas includes a downwardly converging bin, hot gas distributors and a cooling gas distributor. The method whereby the apparatus is used as a reactor dryer to treat particulate sponge iron is also disclosed.