Abstract: A rotating drum filter assembly for thickening lime sludge includes a liquid jet distributor for directing liquid jets against a strip of lime sludge filter cake on the ascending side of the drum. The distributor is positioned on the ascending side of the drum and within 45.degree. of a vertical plane tangential to the drum peripheral surface. The liquid jets are directed so as to disperse the strip in a manner such that substantially all of the lime sludge comprising the strip remains on the drum. Cake wash water formed by water distributed from shower heads immediately refills the cleaned strip thereby minimizing loss of vacuum within the hollow drum interior.

Abstract: The present invention provides an energy conserving process for calcining a clay and apparatus for carrying out the process. A dry pulverized clay powder (1) is fed to a calciner (20) to be calcined therein. The calcined clay product (3) is removed from the calciner (20) and preferably passed in heat exchange relationship with a cooling medium (71) whereby the calcined clay product (3) is cooled and the cooling medium is heated. The hot off-gas (7) discharged from the calciner (20) is passed through an electrostatic precipitator (30) to remove at least a substantial portion of calcined clay product dust (11) entrained in the exhaust gas from the calciner. The clean gas (13) leaving the electrostatic precipitator (30) is passed in heat exchange relationship with a cooling fluid (51) to further cool the gas, and preferably to evaporate at least a portion of the cooling portion to produce a heating vapor (53).

Abstract: A piezoelectric transducer assembly for producing sonar signals for transmission underwater and for detecting reflected sonar signals. The assembly includes a two-dimensional generally planar array of piezoelectric elements disposed in an elastomer casing. The elements are coupled by way of conductors to electronic circuitry which produces electrical signals for stressing the piezoelectric elements and which processes electrical signals produced by the piezoelectric element in response to reflected sonar signals. The piezoelectric elements are closely packed and are selected to have low cross-coupling characteristics. At least some of the elements are oriented so that their axes of polarization are generally perpendicular to the plane of the array.

Abstract: A flexible line array transducer assembly for detecting underwater acoustical signals. The assembly includes an array of spaced-apart piezoelectric elements arranged generally in a line and selected to have low cross-coupling characteristics, low sensitivity to incoherent mechanical perturbations in the directions longitudinal and lateral to the axis of the array, and high sensitivity to coherent mechanical perturbations such as acoustical signals. The elements are polarized in a direction generally transverse to the array and each include opposing surface areas which are generally parallel with the linear axis of the array. Electrodes are disposed on the opposing surface areas of the elements and are coupled to conductors which carry signals produced by the piezoelectric elements when the elements are stressed by acoustical signals. A porous, open-cell material is disposed about the piezoelectric elements as an encasement to maintain the elements in place and mechanically isolate the elements.