Abstract: System and method for producing paper that employ an apparatus for measuring electrical characteristics of a fibrous composition. The apparatus comprises a plurality of conductivity (or resistance) detectors each comprising a sensor that is sensitive to the conductivity (or resistance) and the proximity of the material (e.g., fibrous composition) to the sensor. Measurements from the apparatus relate to the zeta potential of the fibrous materials in the composition. The zeta potential profiles corresponding optimized configurations of the sheetmaking process can be employed to monitor and control the process.

Abstract: Rock and other hard materials, such as concrete, are fragmented by a controlled small-charge blasting process. A cartridge containing an explosive charge is inserted at the bottom of a hole drilled in the rock. The explosive charge is configured to provide the desired pressure in the hole bottom, including, if desired, a strong shock spike at the hole bottom to enhance microfracturing. The cartridge is held in place or stemmed by a massive stemming bar of high-strength material such as steel which blocks the flow of gas up the drill hole except for a small leak path between the stemming bar and the drill hole walls. The cartridge-incorporates additional internal volume designed to control the application of pressure in the bottom hole volume by the detonating explosive.

Abstract: The present invention is directed to a method for breaking rock and other hard materials using small-charge blasting techniques followed by a mechanical impact breaker. In small-charge blasting techniques, a gas is released into the bottom of a sealed hole located in a free surface of the hard material. The gas pressure rises rapidly in the hole until the gas pressure causes the hard material to fracture. The impact breaker is then used to complete fracturing of the material and to remove the fractured material.

Abstract: The present invention is directed to a cartridge for use in fracturing materials, such as rock. The cartridge includes a base member, a body member, a propellant, and a device for sealing a surface of the cartridge to the surface of a hole in the material. Upon ignition of the propellant, gas pressure rapidly rises in the hole due to the sealing device. The gas pressure causes the material to form a penetrating cone fracture. Various cartridge configurations are presented depending upon the specific needs of each application.