Abstract: A double layer cooler for particulate material has a conveyor to which separate streams of such material are delivered at spaced intervals to form lower and upper layers of material on the conveyor. As the layers move toward the discharge end of the conveyor a coolant passes upwardly through the layers. At the discharge end of the conveyor the material of the lower layer is discharged, whereas the material of the upper layer passes over a stationary quantity of material to a crusher in which the upper layer material is crushed. From the crusher material is returned to that stream which forms the lower layer on the conveyor. The lower layer of material thus is precooled and comminuted.

Abstract: The invention relates to a method as well as to apparatus for combined grinding of at least two materials of differing grindability, such as clinker and limestone, wherein the material which is more difficult to grind is pre-crushed to a Blaine fineness of grinding of at least 700 cm.sup.2 /g and there-after is further ground together with the other material to produce the finished material.

Abstract: The invention relates to the comminution of moist mineral material in the comminution zone of a material comminuting machine followed by breaking up of agglomerates which have formed and subsequent wet classification of the broken-up material. A good disagglomerating effect and reliable operation is achieved with relatively compact construction of the apparatus if the comminuted product is subjected to at least an injection of fluid with at least partial disagglomerating effect whilst still within the material bed comminuting machine and immediately after leaving the comminution zone, and afterwards is passed on to the wet classification.

Abstract: In this method according to the invention for extracting metals, starting ore material is subjected to material bed comminution and then leached by the addition of leaching fluid. In order to be able to ensure an optimal yield of metals even in the case of greatly differing particles sizes of the comminuted ore material, the comminuted ore material is divided into oversize material and fine material, whereupon oversize material is delivered to a heap leaching and fine material to a tank leaching.

Abstract: A supporting roller bearing for a rotary drum comprises a supporting roller, supporting on its outer surface a circumferential running surface of the rotary drum. The supporting roller is mounted with axial clearance. A measuring device determines the particular axial position of the supporting roller and is connected by way of a control unit to an adjusting arrangement to alter the angle between the axis of the supporting roller and the axis of the rotary drum as a function of the measured axial position of the supporting roller.

Abstract: A reciprocating grate cooler has a plurality of grate plates mounted on a reciprocable support structure for conveying hot material longitudinally across a grate surface formed by the grate plates. The support structure has passages therein and an inlet for admitting cooling gases into the passages for delivery to the hot material. A stationary cooling gas delivery duct has an outlet adjacent the inlet of the support structure and both are provided with sealing frame plates mounted on the support structure and delivery duct, respectively, in generally parallel, closely spaced relation to one another to provide a wear-free dynamic air seal between the delivery duct and the support structure.

Abstract: Bulk material cooling comprises includes a conveyor having a support surface for transporting bulk material from the conveyor inlet to its outlet. A first material supply chute is provided at the inlet for depositing a quantity of relatively cool material on the conveyor. A baffle is located downstream of the supply chute for leveling the material on the conveyor and forming a uniform thickness layer of such material. A second material supply chute is arranged downstream of the baffle for depositing a layer of relatively hot material atop the first layer. The first layer of material protects the conveyor from the heat of the second layer. Cooling air is passed upwardly through the first and second layer to cool the material.

Abstract: A roller mill having a fixed roller and a floating roller mounted on a frame and driven in opposite directions includes two gear units for the rollers and two independent torque absorbers to minimize the transfer of torque loads to the frame. Each torque absorber has a pair of two arm levers pivoted at spaced axes on the frame so that one end of each lever is adjacent one end of the other. A first force transmitting member couples the adjacent ends of the levers to each other and a second force transmitting member couples the opposite ends of the levers to the associated gear unit.

Abstract: The invention relates to a cooler grate for a reciprocating grate cooler, with a plurality of grate plate supports extending transversely with respect to the cooler grate and constructed as hollow bodies, on which in each case grate plates are supported so that they are co-ordinated in transverse rows and sealed by means of screw connections, wherein the grate plates have cooling gas openings and cooling gas connecting channels are constructed between the grate plate support and the cooling gas openings.

Abstract: A method of desulphurizing flue gases polluted with SO.sub.2 comprising cooling the gases to a temperature of about 0.5 to 20.degree. above the dew point of the gases and flowing the gases through a granular sorbent prepared from a mixture of commercial cement and water.

Abstract: A roll mill has a fixed roll journalled in stationary fixed bearings and a floating roll journalled in movable bearings enabling the floating roll to be pressed against the fixed roll under high pressure. An adjustable spacing arrangement is provided between the two bearings to enable a gap of selected width to be formed between the rolls. The spacing arrangement includes a pair of shaft-like distance members received and guided in associated bores of the fixed bearings for movement therealong. Free ends of the distance members extend outward of their bores and engage the opposing floating bearings to adjust the positions of the rolls as they wear so as to maintain the selected gap width. The free ends are retractable into the bores to allow the bearings to abut one another and thereby optimize the wear life of the rolls.

Abstract: The invention relates to the cooling of hot bulk material, particularly cement clinker, ore material or the like, in a grate cooler, in which the bulk material is transported on the cooler grate surface toward an outlet and exposed to cooling gas from below. At least a part of the relatively cooler lower portion of the material layer is discharged through suitable chutes upstream of the cooler outlet while in transport to increase the cooling efficiency of the process.

Abstract: In this tiltable supporting roller bearing according to the invention for supporting a rotary drum there are provided a freely rotatably mounted supporting roller and an appertaining bearing structure which is tiltably supported with respect to a stationary foundation plate with the aid of easily shifted support bearings which are arranged inclined against one another in such a way that the point of rotation of the line of contact between the supporting roller and the riding ring of the rotary drum lies with the vertical central axis of the supporting roller. With a particularly simple and reliable design, this construction makes it possible to compensate for skewing of the rotary drum riding ring and at the same time markedly to reduce or largely avoid undesirable consequences of the axial forces resulting from longitudinal movements of the rotary drum.

Abstract: The invention relates to a grinding plant and to a method of grinding and classifying brittle material for grinding, in which two classifiers are used. The finer fraction from the first classifier is delivered to a second classifier which separates it into coarse material and fine material. The coarse material passes into a fine grinding mill and from there is conveyed back to the second classifier by way of a mechanically transporting conveyor arrangement.

Abstract: The invention relates to a method of producing cement clinker from fine-grained cement raw material which after preheating and calcining is burnt in a clinker burning zone divided into two stages and is then cooled. Optimum process conditions, particularly in the clinker burning zone, are achieved in that the calcined material is first of all heated to a temperature up to the region of the sintering temperature in a stage formed by a fluidized bed or spouted bed so that a build-up granulation of the material is brought about, whereupon the material thus heated is heated to the sintering temperature in a second stage of the clinker burning zone which acts as the finish-burning stage and tempered to the finishing burn.

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: The invention relates to a rotary drum with relatively large dimensions, the shell of which is supported by means of riding rings each on a pair of supporting rollers of a supporting roller stand. For this purpose the rotary drum shell merely bears two riding rings which are attached so as to be fixed against rotation and which are supported on two supporting roller stands of which at least one simultaneously forms the rotary drive arrangement for the rotary drum in the form of a friction drive. This produces a combination of features by means of which the mounting of the rotary drum is statically determinate and can be driven reliably in an extremely simple manner.

Abstract: The invention relates to the comminution of brittle material for grinding in a material bed roll mill with two grinding rolls, in which the material for grinding is comminuted between the cylindrical surfaces of the grinding rolls by the application of a grinding force. In order to prevent damage to the roll surfaces due to excessively high surface pressures but to utilise the maximum capacity without exceeding it, the roll surface pressure is continuously monitored and when an upper limit is exceeded the pressure is reduced to a permissible value by reducing the grinding force.

Abstract: The invention relates to apparatus for material bed comminution of brittle material for grinding, with two roll-like comminuting tools, in which the length:diameter ratio is in each case less than 1 and of which one tool is fixed and the other is mounted so as to be movable, wherein a working gap distance is maintained between the two comminuting tools in the unloaded starting position and the comminuted material for grinding is substantially pressed to form agglomerated scabs. In order to ensure a relatively low wear and a relatively maintenance-free operation the length:diameter ratio of the comminuting tools is less than approximately 0.3 and the diameter of the roll-like comminuting tools is chosen to be sufficiently great that the scab thickness is always greater than the working gap distance.

Abstract: The invention relates to the comminution of material for grinding, particularly for the production of cement, wherein the material for grinding is comminuted in a mill and the comminution product is classified in a classification zone into fines and oversize material and the oversize material is returned to the mill. With a view to effective influencing of the breadth of the particle size distribution as well as a relatively low specific energy consumption the comminution product is classified in the classification zone in at least two air separators which are connected one behind the other in series, and a proportion of the oversize material from the first air separator is returned directly to the mill, the remaining proportion being delivered to the second air separator.