Abstract: Cement clinker production apparatus having a precalcination stage connected upstream of a rotary kiln, in which precalcination stage a CO-containing reduction zone in the rotary kiln off-gas duct is employed for the purpose of reducing the pollutant NOx. In order to make certain that the quantitative ratio of O2 in the rotary kiln off-gas to fuel admitted by a deNOx burner, and thus control the effectiveness of NOx reduction, a pivoting throttle valve (33) is positioned in the precalcination stage to control the quantity of rotary kiln off-gas and thus the O2 content in the kiln off-gas. The throttle valve (33) is positioned in the rotary kiln off-gas duct (15) above the deNOx burner (19), above the raw meal inlet (13), and before the confluence of the tertiary air substream with the rotary kiln off gas.

Abstract: A shoe bearing for a heavy rotary drum such as a cylindrical casing of a tube mill designed so that all the shoe bearing elements used at each bearing station are always uniformly loaded. One of the two outlying shoe bearing elements (11) is braced directly against the foundation (16) while the other shoe bearing elements (12, 13, 14) of the bearing station are supported on a flexible support cable (17).

Abstract: A system for the manufacture of cement clinker from cement raw meal in which the off-gases of the cement clinker production line not only undergo denitrification but also undergo desulfurization, so that even sulfur-rich raw materials and fuels can be employed without exceeding the prevailing pollutant emission limits. A substream of the oversize material (30) discharged from the mixing chamber (29) of the precalcination stage (16) as solid sorbent may be combined with the off-gas (22) and/or with a partial gas discharge (38) of the rotary kiln off-gas in order to convert the sulfur oxides contained in those off-gases to calcium sulfate (34), which is subsequently separated from the system off-gas.

Abstract: In order to create a process for the economical production of cement clinker in a cement clinker production line with a raw meal preheater, a precalcination stage, a rotary tubular kiln and a clinker cooler, in which the total oxygen excess required for all firing points, i.e., the ratio of total oxygen to total fuel, also designated as &lgr; value, is to lie as low as possible, it is proposed according to the invention, to continuously measure the content of CO and/or (unburned) hydrocarbons and/or other combustion products in the exhaust gas path of the precalcination stage and, in dependence on this measurement value, to perform a regulating intervention on the amount of an oxidation agent and/or catalyst to be injected into the precalcination stage.

Abstract: In cement clinker production installations, especially with short rotary tubular kiln, in order to find a way in which the thermally highly stressed rotary kiln intake chamber can be protected from overstress and therewith the entire production installation can be reliably operated it is proposed, according to the invention, to introduce directly into the rotary kiln intake chamber, a finely granular non-preheated substance usable in the cement clinker production process, to suspend or disperse it there in the rotary kiln exhaust gas and thereby to continuously cool the kiln intake chamber, and to discharge the heated finely granular substance with the exhaust gas from the kiln intake chamber and to add it to the process raw meal or direct it elsewhere.

Abstract: In order to further develop a circuit grinding apparatus with roller mill or roller press for comminution of the material bed of granular material and with at least one integrated sifter, in which mill and sifters are arranged within two fixed side face walls with an interlying turnably borne material conveyor ring settable into rotation for an internal material circuit, so that seals between the fixed side face walls and the interlying material conveyor ring that is settable in rotation are no longer necessary, it is proposed according to the invention to combine the two fixed side face walls over a housing part that houses the rotatable material conveyor ring, especially a ring housing part, into a housing tightly enclosing the entire working space of the circuit grinding apparatus, and to arrange on the underside of the housing part at least one grinding material leakage discharge from the working space of the circuit grinding apparatus.

Abstract: A grate cooler of simple construction whose cooling grate is substantly protected against wear and which can be operated in simple fashion and with a high cooling efficiency. A plurality of rotatably supported tubular oscillating shafts, spaced apart from one another, are arranged transversely to the conveyance direction of cooling feed material above a stationary cooling grate. Upwardly extending shovel arms (16a, 16b, 16c), are attached to the shafts which move with a reciprocating oscillatory motion (17) in the conveyance direction of cooling feed material. The shovel arms have a pushing surface on their forward side and a wedge surface on their rearward side and, in their oscillatory motion, moving the hot bed of cooling feed material successively from the beginning of grate-cooler to the discharge of the grate cooler.

Abstract: In order to create a sifting device with integrated static sifter member and dynamic sifter member having at least one rotatably disposed rod basket such that the two sifter members are optimally coordinated so as to operate efficiently, particularly with moist sifting material to be dried, it is proposed in accordance with the invention to have a bypass line leave from the intermediate area between the static member and the dynamic member of the sifting device for drawing off a partial flow of the sifting air flow/sifting gas flow and to supply only the remaining outgoing sifting air of the static sifter member (static cascade sifter or V-sifter) to the dynamic sifter member with the at least one rotatably disposed rod basket.

Abstract: To construct a tube mill such that a simple and compact circulation grinding system can be created therewith, with little outlay in terms of machinery, that can also manage higher stock circulation rates without high operating costs, a tube mill is disclosed whose drop-delivery housing consists of two spaced stationary non-rotating side faces, between which a rotatably mounted material conveyor ring is arranged, which can be rotated; whereby a sifting space with a dynamic sifter and/or a static sifter is integrated in this so constructed drop-delivery housing.

Abstract: In order to create a calcinator preceding the rotary tubular kiln and equipped with secondary firings in which inert fuels that are difficult to ignite or, respectively, difficult to burn (secondary fuels) can be beneficially disposed of by burning for the purpose of calcination of the cement raw meal and a complete burn-out of CO gas strands and other fuel constituents, as well as an exhaust gas with low Nox, are nonetheless assured for cement clinker production lines, the tertiary air channel in the region of the calcination unit is fashioned as a combustion chamber that expands the channel cross-section and through which the suspension flows from bottom to top. Tertiary air having a torsion component as well as an easily ignitable fuel is centrally introduced at the lower end of the combustion chamber, whereby a high-temperature zone that extends centrally from bottom to top and has a hot core flame proceeds from this burning location.

Abstract: In order to create, for cement clinker production lines, a calcinator that is connected upstream from the rotary tubular kiln and is equipped with two firings, which enables on the one hand a high-grade calcinated raw meal and on the other hand an exhaust gas with very low NOx emissions, as well as a burning that is as complete as possible of remaining CO-containing NOx reduction zones, it is provided that a combustion point with sub-stoichiometric fuel combustion be arranged both in the rotary kiln exhaust gas ascending line and also in the cooler outgoing air line which form a first and section portion, respectively, of the calcinator and that downstream in a flow direction of the suspension, additional combustion air discharges into the calcinator which combustion air is branched off from the tertiary air line coming from the clinker cooler via at least one branch line.

Abstract: In order to create a cyclone separator with segmented immersion pipe for cement clinker manufacturing system with cyclone suspension type heat exchanger system, whereby the releasable immersion pipe segment fastening is dependable and is distinguished by a long service life, it is inventively proposed to secure the immersion pipe segments at their upper end with releasable screw bolts, whereby the screw bolts are arranged in spacer sleeves distributed around the immersion pipe circumference that respectively comprise at least one window-like opening at the outside for the access of ambient air as coolant for the immersion pipe segment fastening.

Abstract: The pinion (10) on the pin shaft (11) and/or the pinion shaft bearings to either side of the pinion and/or the pinion shaft pillow blocks (12, 13) are supported by elastically deformable components (15, 16, 22, 23) so as to automatically adapt radially in an elastically compliant manner to variations in the meshing of the pinion with the rim gear on the driven rotary drum of a tube mill or the like.

Abstract: In order to enable grinding, with the lowest possible specific energy requirement, of brittle grinding material, in particular moist ores and/or other moist minerals, with the use of an interparticle crushing high-pressure roll press in which the roll surfaces are protected against wear by means of a grid armoring by an autogenous wear protection layer, without having to accept the risk of a premature damaging of the wear protection layer given the occurrence of rough particles/oversized particles/scattered particles, a smooth roll mill is connected upstream from the interparticle crushing high-pressure roll press, in whose nip (i.e. that of the smooth roll mill), the nip width is limited to a maximum of approximately 4 mm, such that only the oversized particles (scattered particles) contained in the feed material are coarse-crushed by means of individual particle crushing.

Abstract: A compact circuit grinding apparatus wherein two press rolls are housed in one housing, comprising of two stationary lateral end walls, between which is arranged a material conveyor ring, which is rotatably seated and can be set into rotation, for an internal material circulation. The inflow of material takes place through one or more openings in one or both housing end walls and the outflow of material likewise takes place laterally through one or more openings in the housing end wall. A sifter is arranged underneath the nip of the two rolls in the housing. The sifter can comprise a static or dynamic sifter and a flow of air through the sifter removes the fines from the crushed granular material.

Abstract: A cement plant for the production of cement clinker from cement raw meal has a flat plate shaped control element for distributing and/or transporting-feeding a stream of hot flour-like material which is subjected to severe thermochemical and abrasive ware. the service life of the control element is greatly increased by constructing it as a hollow body (19, 22) through which coolant flows from at least one inlet opening to at least one discharge opening.

Abstract: A method and apparatus is provided for use in cement clinker production apparatuses, particularly those with a short rotary tubular kiln, in which pollutant containing raw meals are utilized, wherein a bypass vent or gas sub-vent, exhausts a sub-stream of the rotary kiln exhaust. It is proposed to introduce meal or processing dust as condensation nuclei into the upper region of the kiln inlet chamber, these nuclei being entrained by the vented gas sub-stream. This vented gas sub-stream is subsequently further cooled by the introduction of water and/or cool air prior to its de-dusting in a dust trap.

Abstract: A magnetic separator comprising a rotatable drum including an axis of rotation and a periphery comprising a plurality of magnet blocks. The magnet blocks are mounted and arranged as circular rings about the axis of rotation. The ith magnet block is magnetized in a predetermined direction defined by .psi..sub.i =-n.rho..sub.i where n is a positive number and .phi..sub.i is an angle described by a line from the center of gravity of the ith block to the axis of rotation and a predetermine radius vector. The spacing between neighboring centers of gravity of the magnetic blocks, expressed as a sector angle, is smaller than or equal to about .pi./2 (n+1).