Abstract:
Waste tires are disposed of in a cement-manufacturing or other mineral-burning process by introducing the tires into the hot gas stream at at least one point between the mineral-inlet end of a rotary kiln and the lowermost cyclone of an associated preheater system, e.g. into the gas stream within a precalciner vessel or riser duct, the tires being maintained in contact with the hot gas for a sufficient period to effect at least partial combustion of the tires. As an alternative, the tires may be introduced into a Lepol grate preheater.
Abstract:
In the case of a process for treating residues and waste materials, in particular household, commercial, and industrial trash, in a first step in the process these materials are treated thermomechanically, for example in a worm extruder, that is, in particular, heated, separated into fibers, and brought to a solid state. Then the materials in the solid state are separated selectively and subjected to a further recycling treatment.
Abstract:
A description is given of an apparatus for shooting of whole automobile tires, preferably into a cement rotary kiln, which apparatus comprises a gun barrel, a charging device for placing automobile tires in the gun barrel, and a device for generating compressed air for propelling the automobile tire through the gun barrel. The gun barrel consists of a tube having a cross-section which is essentially rectangular over its entire length. By designing the gun barrel with a cross-section which corresponds to the cross-section of the automobile tire, the automobile tire will fill out the entire cross-sectional area of the gun barrel thereby making it possible to provide an air pressure behind the automobile tire which is sufficient for propelling the tire through the gun barrel.
Abstract:
A cement kiln having a tire injection system. The tire injection system comprises an entrance chute having an outer end portion protruding outwardly of a wall of the kiln and an inner end portion which protrudes into the kiln. The entrance chute further is disposed such that it is positioned tangentially to the kiln wall. The entrance chute includes a gate assembly having a cam follower assembly and a pivotally mounted gate member. The cam follower assembly causes the gate member to be urged pivotally between open and closed positions in response to movement of the cam follower assembly over a cylindrical camming wall positioned at a predetermined location relative to the kiln. When the cam follower assembly has caused the gate member to open, a plurality of tires or other items forming a source of supplemental fuel are injected into the entrance chute by one or more external tire injecting apparatuses synchronized in operation to rotation of the kiln. The tires or other fuel items are positively propelled at the time the entrance chute is aligned with the injecting apparatus. A dam formed at the inner end portion of the entrance chute prevents highly fluidized material within the kiln from flowing up into the entrance chute and further forms a channel relatively free of the fluidized material into which the tires may be injected during a predetermined portion, or portions, of rotational travel of the kiln. The apparatus thus allows whole tires or other fuel items or packets to be injected without the use of gravity feed and without the turbulence and splashing otherwise associated with previously developed injection systems.
Abstract:
Apparatus, and a method for using the apparatus, for stripping solid material containing at least one volatile organic compound (VOC). The apparatus is provided with a dryer having a heat source to heat the VOC-containing material to a first temperature, hot enough to volatilize the VOC, but below the cracking temperature of the VOC. The VOC in the dryer is volatilized to form VOC gases. A means for combusting the VOC gases (e.g. a kiln) heats the VOC gases with excess air to a second temperature, hot enough to destroy the organics in the VOC gases. Simultaneously the combustion means preferably can be used to treat a kiln processable material to form a desired product. The kiln includes means for feeding the kiln processable material to the heating chamber, means for cooling and recovering the desired product, and means for providing heat for the VOC dryer. The apparatus also includes a conduit for conducting the gases containing VOC from the dryer to the kiln.
Abstract:
The waste (a) is dried in direct heat exchange with hot exhaust gas (r) from a coal-burning plant (10) and both the gas mixture (g) produced during drying (3) and the dry material (t) produced from the waste are fed into the coal-burning plant.
Abstract:
A pyrolyzer-kiln system for generating combustible fume from waste material and supplementing the fuel used to provide heat energy to a clinker kiln. The system includes a pyrolyzer for generating a combustible pyrolytic fume, a kiln for burning the fume as part of a cement-forming process, a conduit for conveying the fume from the pyrolyzer to the kiln, and a closed-loop feedback component for monitoring the heating value of the fume and varying the operational parameters of the pyrolyzer to maintain the heating value of the fume generated within a predetermined range. The closed-loop feedback component includes a calorimeter which continuously samples and burns fume from the conduit. The heating value of the fume is determined by measuring the amount of auxiliary fuel and air required to be mixed with the fume to maintain a predetermined temperature when the combustion is burned within the calorimeter. Controllers monitor the amount of auxiliary fuel and air supplied to the calorimeter and vary the temperature within the pyrolyzer to effect an increase or decrease in the heating value of the fume. The system also includes a burner pipe for injecting the fume into the kiln which has a variable orifice to maintain a constant pressure differential across the orifice and thereby maintain a predetermined flame shape as the fume is burned in the kiln.
Abstract:
Excavatged landfill material is treated in a plasma fired cupola in a process wherein hazardous material such as PCB's are volatilized and consumed in an afterburner above the cupola and hazardous materials containing heavy metals are fixed in vitreous material made molten within the cupola and resulting in a non-leachable solid product.
Abstract:
A method and apparatus of cofiring hazardous organic waste in solid, pasty, greasy or sludge form by introducing it directly into the burning zone of an industrial rotary kiln and burning the waste in the burning zone simultaneously with cement, lime or lightweight aggregate. Specifically disclosed are five exemplary embodiments for introducing the waste directly into the burning zone of the kiln, i.e., (1) through a side opening in the kiln, (2) ballistically, (3) by pre-mixing with a powder or granular material and pneumatically injecting the non-sticky mixture, (4) by shredding steel drums containing the waste and thereafter separating the drum fragments and mixing the remaining waste with powder or granular material (i.e. as in (3) and (5) by pregasification of the waste.
Abstract:
An apparatus is provided for charging containerized fuel, particularly combustible hazardous waste homogenates, through a wall of a rotating kiln with minimal perturbation of mineral processing conditions. During kiln rotation fuel modules are loaded into the apparatus and charged into the kiln through a port in the kiln cylinder wall and onto the contained mineral bed. In a preferred embodiment the apparatus includes a device for actuating a port closure and a drop tube extending from the port into the kiln cylinder and positioned so that in-process mineral material does not contact the port closure during rotation of the kiln cylinder.