Abstract: A method is described for reducing NOx emissions and improving energy efficiency during mineral processing in a rotary kiln. The method comprises injection of air with high velocity/high kinetic energy into the kiln to reduce or eliminate stratification of kiln gases. The method can be applied to mix gases in a rotary kiln vessel or in a preheater/precalciner vessel.

Abstract: A method is described for reducing NOx emissions and improving energy efficiency during mineral processing in a rotary kiln. The method comprises injection of air with high velocity/high kinetic energy into the kiln to reduce or eliminate stratification of kiln gases. The method can be applied to mix gases in a rotary kiln vessel or in a preheater/precalciner vessel.

Abstract: A printer controller for processing print data includes a data processor, direct memory access controller, first and second memories with corresponding first and second transfer data busses. A bus switch selectively connects the first and second data transfer busses. When uncoupled, the data processor accessed the said first memory via the first data transfer bus and the direct memory access controller may independently accesses the second memory via the second data transfer bus. When connected, either the data processor or the direct memory access controller may access either memory to the exclusion of the other. This permits better allocation of data transfer bandwidth in the memory controller.

Abstract: This invention comprises a converged printer architecture for controlling both electro-photographic (EP) processing and raster image processing (RIP) of data for laser modulation over a video line. By converging EP process control with image processing control, significant advantages in cost, image quality, and output stability are achieved. A digital signal processor (DSP) serves as the central processing resource of the architecture. The DSP is well suited for the dual role of image processing and real-time feedback process control. The DSP can operate in open loop motor/motion control, print process control, and in closed loop feedback control including image processing adaptations for quality and stability enhancements.

Abstract: A method is described for reducing NOx emissions and improving energy efficiency during mineral processing in a rotary kiln. The method comprises injection of air with high velocity/high kinetic energy into the kiln to reduce or eliminate stratification of kiln gases. The method can be applied to mix gases in a rotary kiln vessel or in a preheater/precalciner vessel.

Abstract: A method and apparatus for controlling the combustion of fuel modules charged into a preheater or precalciner kiln above the transition shelf, typically into the riser duct, is described. The apparatus includes a sensor for providing signals indicative of the status in the region of combustion of the fuel modules, and a controller for a fuel module feed mechanism is provided to receive signals indicative of the status of the combustion region and adjust the rate of delivery of the fuel module into the combustion region responsive to the sensed conditions in the combustion region.

Abstract: A method and apparatus is described for environmentally sound usage of combustible hazardous waste as supplemental fuel in operating rotary cement kilns. The apparatus comprises an open port in the rotary vessel at a point where during cement kiln operation the in-process mineral material is in a calcining state and where kiln gas temperatures are sufficient to decompose volatile components of the waste fuel. A drop tube extending from the port into the kiln is provided to prevent in-process mineral from escaping through the port during rotation of the rotary vessel. Combustible solids are delivered through the port under the force of gravity and air is continuously drawn into the rotary vessel through the open port during kiln operation. The apparatus and method allow efficient usage of combustible solid waste as a supplemental fuel for cement kiln operation.

Abstract: A multilevel hierarchical least recently used cache replacement priority in a digital data processing system including plural memories, each memory connected to said system bus for memory access, a memory address generator generating addresses for read access to a corresponding of the memories and a memory cache having a plurality of cache entries, each cache entry including a range of addresses and a predetermined set of cache words. During each memory read the comparator compares the generated address with the address range of each cache entry. If there is a match, then the cache supplies a cache word corresponding to the least significant bits of the generated address from the matching cache entry. If there is no such match, the generated address is supplied to the memories and a set of words is recalled corresponding to the generated address. This set of words replaces a least recently used prior stored memory cache entry having the lowest priority level.

Abstract: A preheater or precalciner kiln is modified to feed solid fuel into a riser duct of the kiln to enable efficient environmentally sound use of solid waste-derived fuel. The modified kiln includes a solid fuel delivery port in the riser duct, a fuel feeder device for feeding solid fuel through the delivery port, and a fuel suspension device for holding the solid fuel for combustion in a fixed position in the kiln gas stream.

Abstract: Novel cementitious systems comprised of gypsum, calcined clay, and clinker consisting essentially of hydraulic calcium silicates are disclosed which have the following properties: (1) a water demand of less than about 33% nc; (2) one-day strengths of at least about 1000 psi; and (3) low alkali functionality. By increasing the amount of calcined clay, the resulting cementitious system will sequentially gain the following properties: (1) alkali non-reactiveness; (2) alkali resistance; and (3) low chloride permeability. Novel methods of preparing the novel cementitious systems of this invention are also disclosed. The novel methods not only reduce production costs by decreasing fuel and raw material consumption, but they also allow the cement producer to proactively address significant environmental concerns related to the manufacturing process.

Abstract: A method and apparatus are described for environmentally sound usage of combustible solid waste in operating rotary cement kilns. A cement kiln is modified to contain a port in the rotary cylinder for delivery of combustible solid waste into the kiln for burning in contact with calcining mineral material. The port is provided with a closure and means for moving the closure between a port-opened and port-closed position at predetermined times during rotation of the kiln cylinder. The invention allows efficient use of solid waste as supplemental fuel in the cement manufacturing process.

Abstract: A method and improved apparatus is disclosed for improving combustion efficiency and reducing emission of gaseous pollutants during the manufacture of cement in conventional long rotary kilns. Air is injected through a port in the wall of a rotary cement kiln having a secondary burning zone established by burning solid fuel in contact with the in process mineral at a point downstream, relative to kiln gas flow of the clinkering zone in the kiln. The air injection apparatus is designed to enhance mixing of the injected air with the kiln gas stream and is characterized by high linear flow rates and/or multi-directional air injection ports. The air injection ports can be located downstream of a secondary burning zone to provide staged combustion with concomitant reduction in concentration of NO.sub.x, CO and hydrocarbons in the kiln gas stream.

Abstract: Novel cementitious systems comprised of gypsum, calcined clay, and clinker consisting essentially of hydraulic calcium silicates are disclosed which have the following properties: (1) a water demand of less than about 33% nc; (2) one-day strengths of at least about 1000 psi; and (3) low alkali functionality. By increasing the amount of calcined clay, the resulting cementitious system will sequentially gain the following properties: (1) alkali non-reactiveness; (2) alkali resistance; and (3) low chloride permeability. Novel methods of preparing the novel cementitious systems of this invention are also disclosed. The novel methods not only reduce production costs by decreasing fuel and raw material consumption, but they also allow the cement producer to proactively address significant environmental concerns related to the manufacturing process.

Abstract: The present invention is directed to a method for controlling the kiln gas stream in a conventional long wet or dry process cement kiln modified for delivery of solid fuel into the calcining zone. Air is injected into the kiln gas stream at a point downstream of the clinkering zone and upstream of the drying zone to promote combustion efficiency downstream of the clinkering zone.

Abstract: The present invention is directed to a method and apparatus for controlling the kiln gas stream in a conventional long wet or dry process cement kiln. A portion of the kiln gas stream can be withdrawn from the rotary kiln vessel at a point upstream, relative to kiln gas flow of the chain system in the mineral drying zone. Alternatively, or in conjunction with bypass formation, the apparatus can be used to add tertiary air to the kiln gas stream to promote combustion efficiency downstream of the clinkering zone. Use of the present apparatus to form a kiln gas bypass stream enhances operating efficiencies of long kilns by reducing dust loss, by facilitating isolation of high alkali by-product streams, by reducing alkali content of collected kiln dust, by increasing energy efficiency of long kiln operation, and by allowing greater overall control in the cement manufacturing process.

Abstract: The present invention is directed to a method and apparatus for controlling the kiln gas stream in a conventional long wet or dry process cement kiln. A portion of the kiln gas stream can be withdrawn from the rotary kiln vessel at a point upstream, relative to kiln gas flow of the chain system in the mineral drying zone. Alternatively, or in conjunction with bypass formation, the apparatus can be used to add tertiary air to the kiln gas stream to promote combustion efficiency downstream of the clinkering zone. Use of the present apparatus to form a kiln gas bypass stream enhances operating efficiencies of long kilns by reducing dust loss, by facilitating isolation of high alkali by-product streams, by reducing alkali content of collected kiln dust, by increasing energy efficiency of long kiln operation, and by allowing greater overall control in the cement manufacturing process.

Abstract: A method is described for environmentally sound usage of combustible hazardous waste in an operating rotary kiln. The method is particularly adapted for disposal of solid hazardous wastes, optionally in the form of a blended waste homogenate, packaged in sealable containers. The containers are used as fuel modules and charged into a rotary kiln cylinder where kiln gas temperatures range from about 950.degree. to about 1200.degree. C. to achieve high destruction and removal efficiencies.

Abstract: A disposable shower curtain including a holder having a mandrel with inner and outer telescoping segments normally expanded by a spring. Stationary feet, one carried by each of the telescoping segments, bears against the opposed walls of a conventional shower stall and rotatably support the mandrel. A roll of coiled sheet material is carried by the mandrel. A shield supported by a bracket at either end thereof includes a longitudinally extending braking panel.

Abstract: A method is described for environmentally sound usage of combustible hazardous waste in an operating rotary kiln. The method is particularly adapted for disposal of solid hazardous wastes, optionally in the form of a blended waste homogenate, Packaged in sealable containers. The containers are used as fuel modules and charged into a rotary kiln cylinder where kiln gas temperatures range from about 950.degree. to about 1200.degree. C. to achieve high destruction and removal efficiencies.

Abstract: A method is described for environmentally sound usage of combustible hazardous waste in an operating rotary kiln. The method is particularly adapted for disposal of solid hazardous wastes, optionally in the form of a blended waste homogenate, packaged in sealable containers. The containers are used as fuel modules and charged into a rotary kiln cylinder where kiln gas temperatures range from about 950.degree. to about 1200.degree. C. to achieve high destruction and removal efficiencies.