Abstract: A continuous digester comprises a wash zone having a plurality of individual wash screens disposed about an inner wall of the digester for the withdrawal of co-current downflow liquor from the wash zone. A conduit is connected in fluid communication between each of the wash screens and a collector for co-current downflow liquor withdrawn from the wash zone of the digester. A valve is interposed along the length of the conduit leading from each of the wash screens. The valve is operable between open and closed positions in response to a signal received from a temperature sensor associated with the conduit leading from each of the wash screens.

Abstract: A continuous digester comprises a wash zone having a plurality of individual wash screens disposed about an inner wall of the digester for the withdrawal of co-current downflow liquor from the wash zone. A conduit is connected in fluid communication between each of the wash screens and a collector for co-current downflow liquor withdrawn from the wash zone of the digester. A valve is interposed along the length of the conduit leading from each of the wash screens. The valve is operable between open and closed positions in response to a signal received from a temperature sensor associated with the conduit leading from each of the wash screens.

Abstract: This invention is directed to a method for cooking wood chips in a digester for the separation of wood fibers from their bonded state, the digester having a vertical centerline, a substantially circular cross-section, and a wash zone adjacent the bottom end thereof and a plurality of individual wash screens disposed about the inner wall of the digester for the withdrawal of liquor from the wash zone. In the first step of the method, substantially equal volumes of liquor are dynamically withdrawn from the wash zone through individual ones of the wash screens, while monitoring of the flow rate of liquor exiting the digester through individual ones of the wash screens. The monitored flow rate is used to increase or decrease the flow rate from screens to a value substantially equal to the flow rate of liquor from the digester through each of the screens.

Abstract: An active vibration control system including a sensor responsive to a source of vibration and which provides an output signal representative of the vibrations; at least one actuator positioned to impart canceling vibrations to the source of vibrations based on an input signal; a correction subsystem responsive to the actuator for estimating the sensor output in the absence of the canceling vibrations and which outputs a corrected output signal representative only of the vibrations emanating from the source; and a state space predictor responsive to the corrected output signal for determining the input signal to the actuator based on variations in the corrected output signal to better control vibrations especially in chaotic systems.

Abstract: This invention is directed to a method for cooking wood chips in a digester for the separation of wood fibers from their bonded state, the digester having a vertical centerline, a substantially circular cross-section, and a wash zone adjacent the bottom end thereof and a plurality of individual wash screens disposed about the inner wall of the digester for the withdrawal of liquor from the wash zone. In the first step of the method, substantially equal volumes of liquor are dynamically withdrawn from the wash zone through individual ones of the wash screens, while monitoring of the flow rate of liquor exiting the digester through individual ones of the wash screens. The monitored flow rate is used to increase or decrease the flow rate from screens to a value substantially equal to the flow rate of liquor from the digester through each of the screens.

Abstract: An active vibration control system including a sensor responsive to a source of vibration and which provides an output signal representative of the vibrations; at least one actuator positioned to impart canceling vibrations to the source of vibrations based on an input signal; a correction subsystem responsive to the actuator for estimating the sensor output in the absence of the canceling vibrations and which outputs a corrected output signal representative only of the vibrations emanating from the source; and a state space predictor responsive to the corrected output signal for determining the input signal to the actuator based on variations in the corrected output signal to better control vibrations especially in chaotic systems.