Abstract: The present invention pertains to a grate plate utilized in a cooling apparatus.Substantially the entire surface area of the exposed surface is defined by alternating rows of a plurality of (1) substantially rectangular hollow air distribution plenums that travel substantially the entire length of the exposed area in a direction parallel to the movement of solid material through the cooling apparatus. The air distribution plenums have two side walls and a top surface with which the solid material transported to the cooling apparatus comes into contact, and (2) a plurality of pockets that also travel substantially the entire length of the exposed area in a direction parallel to the movement of solid material through the cooling apparatus. The said side walls of the air distribution plenums each have a plurality of air outlets or portals located thereon through which cooling air passes from the hollow interior of the air distribution plenum into a pocket located adjacent thereto.

Abstract: Disclosed is an apparatus and a method for the comminution of brittle material in a roll crusher. The method comprises the steps of introducing fresh material feed into a roll crusher which is divided into two distinct feed inlet zones which are at least one initial feed inlet zone for said fresh feed material and at least one secondary feed inlet zone for feed which has been stressed at least once by said roll crusher. Each initial feed inlet zone and each secondary feed inlet zone directs feed into, respectively, a corresponding initial feed crushing zone and secondary feed crushing zone. In the invention, fresh feed material is introduced into the roll crusher only in the initial feed inlet zone(s) whereby it is stressed at pressures sufficient high to cause the formation of at least some agglomerates.

Abstract: A fluidizing gravity conveyor for hot particulate material which includes a heat resistant plate having a plurality of holes for receiving bubble caps or nozzles to disperse air flow from a lower plenum chamber to the upper material chamber. The upper material chamber is suitably lined with heat resistant material. Provisions are made for differential thermal expansion.

Abstract: A process and apparatus for manufacturing low sulfur cement clinker from cement raw meal containing sulfur or with fuel containing high levels of sulfur or a combination thereof. The process is carried out in an apparatus which includes a preheater, calcining furnace, clinkering furnace and clinker cooler. A separate source of fuel is added to the feed end of the kiln to maintain reducing conditions and temperatures for decomposing the sulfur compounds. Fresh air is added to the riser duct connecting the clinkering furnace with the calcining furnace and the preheater for converting sulfur dioxide to sulfur trioxide. Calcium oxide is added to the riser duct for absorbing the sulfur trioxide to form calcium sulfate. The calcium sulfate is then removed by a gas solid separator from the system. Excess fuel added to maintain reducing condition at the feed end is utilized in the calcining furnace.

Abstract: An improved apparatus for roasting fine material which includes recirculation of at least partially roasted material through the roasting furnace for further roasting. An adjustable gate is included in the recirculation system for controlling the quantity of material recirculated. A high temperature fluidizing gravity conveyor is used in the recirculation system to maintain a low profile for the system. The invention utilizing a system for classifying large particles so that they may be removed from the recirculation system. Gas locks are included for preventing the short circuiting of hot gases. The system also includes overflow conduit in the event of a plug or blockage in the system.

Abstract: A process and apparatus for manufacturing low sulfur cement clinker from cement raw meal containing sulfur or with fuel containing high levels of sulfur or a combination thereof. The process is carried out in an apparatus which includes a preheater, calcining furnace, clinkering furnace and clinker cooler. A separate source of fuel is added to the feed end of the kiln to maintain reducing conditions and temperatures for decomposing the sulfur compounds. Fresh air is added to the riser duct connecting the clinkering furnace with the calcining furnace and the preheater for converting sulfur dioxide to sulfur trioxide. Calcium oxide is added to the riser duct for absorbing the sulfur trioxide to form calcium sulfate. The calcium sulfate is then removed by a gas solid separator from the system. Excess fuel added to maintain reducing condition at the feed end is utilized in the calcining furnace.

Abstract: An attached tube cooler for a rotary kiln for cooling solid particulate material discharged from the kiln. The cooler includes a plurality of cylindrical vessels attached to and circumferentially spaced around the discharge end of the kiln for rotation therewith. Each cooler tube has an inlet for solid particulate material communicating with the outlet of the kiln, an outlet for cooled solid particulate material, an inlet for cooling gas and an outlet for gas which communicates with the kiln so that gas heated in the cooler tube can be supplied as combustion air to the kiln. Heat exchange fins are mounted inside the cooling tube at an angle such that the trailing surface of the fins in the direction of tube rotation forms an acute angle with the side wall of the cooler tube. A helical conveyor having a central opening therethrough advances material through the cooler tube.