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: The invention utilizes fluid bed air heaters for burning coarse solid fuels which supply heated gases to annular shaft kilns or double inclined shaft kilns. The solid fuels are introduced into a fluidized bed of inert material, such as sand, alumina or ash, through means of an air lock and the hot gases of combustion pass through a cyclone separator to remove solid materials, which can be reintroduced into the fluidized bed. The hot gases are injected into the kilns to supply heat as needed for calcining or burning limestone or similar materials. Temperature control of the gas leaving the fluid bed air heater and reduced contamination of the burned materials are disclosed advantages of the present invention.

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: 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: A pneumatic system for exerting a downward grinding force on the roller assemblies of a roller type grinding mill. The pneumatic system consists of a plurality of resilient and flexible pneumatic cylinders or bellows operatively connected through a crank arm, a horizontal rotatable shaft and lever to the roller assembly. The flexible pneumatic cylinders exert an upward force on the crank arm which in turn exerts a downward force through the rotatable shaft and lever on the grinding roll. Vertical movement and vibration of the roller assembly is absorbed by the flexible cylinder to maintain a steady grinding force on the rollers.

Abstract: A conveying apparatus includes a casing having a bore therethrough with an inlet for solid particulate material to be conveyed and an outlet. A screw impeller is rotatably mounted in the casing by front and rear bearings with the rear bearings being positioned near the inlet. Material is discharged from the casing through a coaxial outlet into a discharge chamber. Gaseous fluid under pressure is supplied to the discharge chamber for entraining and conveying the particulate material through a pneumatic conveying line which is flow connected to the outlet of the discharge chamber. A valve, which closes the outlet of the casing, is biased closed by a weight and opened by material being advanced by the screw impeller. The valve includes a valve plate with an opening which surrounds the shaft of the screw impeller and provides a seal at the casing to substantially prevent gaseous fluid from entering the casing.

Abstract: A wear resistant pipe elbow for use in transporting fluent materials such as in a pneumatic conveying system. The elbow includes a wear back or wear resistant surface on the inside of the outer wall of an arcuate channel connecting an inlet leg with an exit leg of the elbow. The wear resistant surface may include a plurality of steps which extend symmetrically toward the inlet leg and the outlet leg. The center of the steps is preferably located on a radius extending from the center of curvature of the arcuate channel through the junction of the longitudinal axis of the inlet leg and the longitudinal axis of the outlet leg. The wear back or wear resistant surface may be made up of a member including a plurality of ribs which defined spaced apart pockets. These pockets are designed to receive and at least partially retain material being conveyed through the system. While the ribs or steps in the wear resistant backing will wear, the depth of metal in this area will prolong the life of the elbow.

Abstract: A grate plate and a combination of a grate plate and support apparatus for a reciprocating grate type material transport apparatus. The support apparatus includes spaced apart forward posts having an interconnecting transverse bar and spaced apart rearward posts having an interconnecting transverse bar. The grates include a transverse lower rib with a protrusion which permits the grate to be secured to the forward posts. The grate includes downwardly extending wings along each side. The rear end of each wing includes a detent that cooperate with the bar interconnecting the rear posts. Protrusions in the midsection of the grate rest on the forward posts. Each grate is thus supported at four points.

Abstract: A method and apparatus for producing cement which includes intermixing the cement forming raw materials with water, coal or coke and cement as a binder and forming this mixture of materials into nodules by pelletizing or extrusion. The system is particularly designed for use in making white cement where raw materials low in coloring compound are used as raw feed. The nodules are then sized to obtain a feed material having a size range on the order of one quarter inch by 14 mesh which is suitable for use in a fluidized bed reactor. The nodulized raw material is thermally processed in a fluidized bed reactor at temperatures in the range of approximately 2500.degree. to 2700.degree. F. for white cement and 2350.degree.-2450.degree. F. for typical gray Portland Cement. The coal or coke mixed with the raw material serves to supply between 60% and 90% precent of the fuel required for the process with the remainder being supplied directly to the fludized bed.

Abstract: A process of treating the dust catch from a cement manufacturing operation to produce either cement clinker or an intermediate product suitable for feed to a conventional cement clinker production facility. A biproduct of enriched alkali and sulfur compounds is also produced. The process includes a feed preparation stage where dust catch, coal or coke and a binder such as cement are combined. Additives to correct the material chemistry may also be added. This mixture is formed into nodules which are dried and then sized to form a feed material. The feed material is processed at or near cement clinkering temperatures in a fluidized bed reactor to volatilize alkali and sulfur compounds and products the intermediate product or cement clinker. Suitable heat recovery devices are utilized in the product cooling phase.

Abstract: A pneumatic conveying and material blending system which includes a bin having an open vertical column mounted therein with a bottom of a column being spaced from the bottom of the bin. The material inlet is located in the bottom of the bin and a pneumatic conveying system supplies material to be blended from a source to the material inlet and conveys the material upwardly through the column so that the material is discharged from the top of the column in the manner of a geyser whereby it is spread over the top surface of material already in the bin. Material already in the bin flows down through the bin by gravity and is entrained by the upwardly flowing gas stream and conveyed up the column so that material already in the bin is blended with material being supplied to the bin.

Abstract: An apparatus and process for calcining gypsum is disclosed which utilizes a flash furnace for rapidly calcining fine particulate gypsum while the material is suspended in a stream of hot gas. The method and apparatus utilize a two-stage suspension preheater for utilizing waste gases from the calcining furnace for preheating raw material to be calcined and a two-stage suspension cooler for cooling hot calcined gypsum which is discharged from the calcining furnace. Spent cooling gas is supplied to the preheater for use in preheating the fresh gypsum to be calcined. The invention also contemplates recirculating a portion of the gypsum discharged from the furnace back to the furnace for further calcination. Hot product may be discharged directly from the furnace.

Abstract: A pneumatic conveying and material blending system and method which includes a bin having an open-ended vertical column mounted therein with the bottom of the column being spaced from the bottom of the bin. The material inlet is located in the bottom of the bin and a pneumatic conveying system supplies material to be blended from a source of the material inlet and conveys the material upwardly through the column so that material is discharged from the top of the column in the manner of a geyser whereby it is spread over the top surface of material already in the bin. The material already in the bin is drawn into the bottom of the column so that material already in the bin is blended with material being conveyed to the bin. A deflector is positioned over the top of the column to aid in spreading the incoming material. Booster gas can be supplied through a section of the bin adjacent the bottom of the column.

Abstract: A combined storage silo and homogenizing device for powdery materials such as cement raw meal. A silo is divided into an upper storage vessel and a lower homogenizing chamber. The storage silo has a slab floor having a plurality of spaced apart openings therein which serve as outlets for the vessel and communicate with inlets for the homogenizing chamber. The homogenizing chamber includes a small pneumatic blending device having a lateral outlet in its bottom feeding blended material to a column having a top outlet for the device.

Abstract: A pressure relief device for pneumatic conveying lines to serve as a safety device in the event of an explosion or sudden pressure increase within the conveying line. The device includes a pair of semi-cylindrical shells normally joined together by a shear pin or pressure sensitive key which ruptures when excessive pressure in the conveying line exerts excessive force on the shell sections. When the joining device ruptures, the shell sections open up to relieve line pressure. A suitable mounting arrangement is provided including guide bars for the shells, bumpers and spring return arrangement.

Abstract: In a fabric filter dust collector of the type including a plurality of elongated tubular fabric filter elements with an inlet for gas and entrained solids, an outlet for filtered gas and an outlet for separated solids wherein the gas and entrained solids enter the dust collector, the gas passes through the fabric filters to the outlet of the collector and particulate material is collected on the surface of the tubular filter elements. A sonic horn cleaning system including sound generators or horns are positioned in the dust collector which when sounded transmit energy to the filter elements to remove the filter cake from the tubular filter elements. A system is provided for determining whether the horns are operating and includes a tube connected to the vent of the horn which tube passes through the casing wall to a remote location where a sound detecting device can be utilized to pick up sound waves transmitted through the tube from an operating horn.

Abstract: Apparatus for conveying solid particulate material which takes the form of a line charging device for a pneumatic conveying system. The apparatus is of the type which includes a screw impeller rotatable in a casing for advancing material from a hopper through the casing to a discharge chamber. From the discharge chamber, gas under pressure entrains the material and serves to convey it through an attached conveying line. A pair of diametrically opposed outlets from the casing are provided to introduce material from the casing into the discharge chamber. A normally closed flap valve is operatively associated with each of the casing outlets to aid in establishing a seal of material at the outlet. The use of nozzles between the source of gas under pressure and the conveying line has been eliminated.

Abstract: A division head for a tubular grinding mill for controlling the level of material being ground in the upstream compartment of the mill. The division head is formed by a plurality of hollow pie shaped segments covered on the upstream side by grates which permit material to flow into the division head and liners and on the downstream side. A partition divides the pie shaped segments into radially inward sections and a radially outward section. Material within the radially inward sections flows out of the division head into a downstream compartment of the mill through a central discharge cone. Some of the radially outward sections are flow connected directly to the radially inward sections through an opening in the partition dividing the pie shaped segments. Dampers are provided for controlling flow of material through the opening connecting radially outward sections with radially inward sections.

Abstract: A flap valve used for selectively closing an open-end of a material conduit. The flap valve is particularly adapted for use in high temperature installations such as at the discharge of a high temperature cyclone separator. The valve includes a shaft rotatably mounted in a fixture properly positioned relative to the conduit to be closed. The shaft includes a polygonal central section and a flap with a top surface adapted to close the open end of the conduit and one end of the flap lies atop the polygonal section of the shaft. The back of the flap is bent perpendicular to the top surface to overhang the shaft. A dog having a similarly shaped polygonal opening slides over the central section of the shaft and has a leg which lies atop the top surface of the flap. This dog serves to transmit rotational forces between the shaft and the flap while allowing relative movement between the shaft on the flap in a direction parallel to the shaft axis to permit relative thermal expansion.

Abstract: A method and apparatus for roasting fine grained ores such as cement raw meal, lime, dolomite, gypsum, phosphate rock and the like. A suspension preheater consisting of a plurality of serially connected cyclone separators is utilized to preheat the raw material. A suspension type roasting furnace follows the suspension preheater which is, depending upon the material being treated, followed by either a rotary kiln for further heat treatment of the material or by a cooler for cooling the product. The apparatus includes an arrangement for recirculating a portion of the material which has passed through the roasting furnace back into the roasting furnace to increase the degree of roasting. An existing preheater, suspension type calciner, rotary kiln cement clinker producing plant can be converted to the method and apparatus by the addition of an appropriately located splash plate.