A sensor, sensor disk, sensor measurement correction system, and method used in measuring a parameter in the refining zone. The sensor includes a spacer that spaces its sensing element from the disk. In one preferred embodiment, the spacer is made of an insulating material that insulates the sensing element from the thermal mass of the disk to prevent the thermal mass from affecting sensor measurement. The sensor includes a housing carried by the spacer that, in turn, carries the sensing element. Where the sensing element is a temperature sensing element, the housing is thermally conductive and the housing and spacer enclose the sensing element. Each sensor is disposed in the refining surface, preferably in its own separate bore in the disk and flush with or below axial refiner bar height. Signals from one or more sensors are processed by a processing device linked to a module containing calibration data that is applied to make sensor measurements more accurate. The module holds calibration data from sensors that are precalibrated before the sensor disk in which they are assembled is shipped, along with the module, to a fiber processing plant where the disk is installed in a refiner and the module connected to the processing device. In one preferred embodiment the sensor or sensors are carried by a sensor module that can be a removable segment of a refiner disk.

A sensor assembly and coupling arrangement for a rotary disk refiner. The sensor assembly includes a housing formed by a base and frustoconical cap that has a sensing element carrying bulb extending outwardly therefrom. The coupling arrangement includes a conduit arrangement that is received in one or more aligned preexisting instrument ports of the refiner and that releasably couples with a connector puck. The puck is carried by the backside of a refiner disk segment that lies next to the refiner disk segment that is equipped with one or more sensor assemblies. Preferably, a flexible hose communicates sensor wiring from a sensor manifold that holds a plurality of sensor assemblies to the connector puck. The sensor manifold preferably is carried by the backside of the sensor refiner disk.

A system and method for monitoring and control operation of a rotary disk refiner. A characteristic of stock in the refining zone is monitored and used to adjust a parameter, such as dilution water, feed screw speed and/or refiner gap to keep some variable substantially constant, close to a setpoint, within a range of the setpoint, close to a setpoint profile based on a distribution of a characteristic over the refining zone or a setpoint profile range. Refiner disk bar angle can be optimized to reduce refining zone temperature and energy use. Thereafter, the control method can be employed. One control method attempts to keep specific energy substantially constant by keeping a ratio between load and production substantially constant. Load is kept substantially constant by regulation dilution flow to keep refining zone temperature substantially constant. The feed screw is regulated to keep production substantially constant.

A system (30) and method for determining stock consistency and for using consistency as a process variable to control some aspect of operation of a refiner (32) used to refine stock. The system includes at least one sensor (70 or 180) from which some refiner characteristic is obtained that is used by a processor (38) in determining consistency. The method uses the characteristic, such as temperature or pressure inside the refiner or in a refining zone (304) of the refiner, along with at least one other refiner parameter in determining consistency. A controller (274) uses the consistency determined in controlling some aspect of refiner operation. In one preferred controller, consistency is compared with a consistency setpoint and adjustments are made to try to converge consistency with the setpoint. The controller can be paused to accommodate other changes made to refiner operation and released when steady state refiner operation is achieved.

A system and method for monitoring and control operation of a rotary disk refiner. The method regulates refiner operation in response to a process variable preferably in relation to a setpoint. The variable can be temperature, pressure, and/or stock consistency, refiner energy, or a variable based thereon. Volumetric flow rate of stock and/or the flow rate of dilution water can be regulated. Based on a refiner temperature, pressure, and/or stock consistency, refiner energy, or a variable based thereon, the flow rate of stock and/or dilution water can be regulated. Where temperature is used, it preferably can be a temperature inside the refiner or adjacent the inlet or outlet. Where pressure is used, it preferably can be a pressure inside the refiner or adjacent the inlet or outlet. Stock consistency can be determined using a sensor upstream or downstream of the refiner or using a sensed parameter in the refiner.