59results about "Beating/refining control devices" patented technology

Thermomechanical pulp is an important process for producing fibrous mass used in papermaking. A two-level control strategy that stabilizes and optimizes the refining process has been developed. The Stabilization layer consists of a multivariable model predicative range controller that regulates the refiner line operations. The Quality Optimization layer provides the pulp quality control as measured by an online pulp quality (freeness, fibre length) sensor. This control startegy leverages the natural decoupling in the process. The modular design technique is able to handle multiple refiner lines that empty into a common latency chest. A global optimizer is also used to integrate and coordinate the two layers for enhanced constraint handling.

A method and a control system for a refiner for pulp or like materials, the control system comprising a sensor mounted in direct mechanical connection to a non-rotating refining member so that the sensor is responsive to axial vibration movement of the support, and an analog to digital converter connected to the output of the sensor. The method and control system also include a controller connected to the analog to digital converter and responsive to the analog to digital converter to compare the amplitude of the output signal from the sensor to a baseline value based on the level of vibration associated with the pulp refiner when it is operating without plate clashing. When the signal exceeds the baseline value, an action is taken to help alleviate the plate clashing.

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.

This invention relates to a method of diagnosing or controlling a grinding mill for paper pulp, wood chips, or other fibrous materials, by measuring the incremental change in power related to an incremental change in the gap, and using the ratio of the two differences, together with the measure of applied power, as the diagnostic or control parameter.

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.

The invention relates to a method for defibering recycled fiber material in a drum pulper provided with a substantially horizontal drum. Recycled fiber material and water are fed to the drum pulper and the drum of the drum pulper is simultaneously rotated. When the drum rotates, the recycled fiber material rises up in the rotating drum and finally, due to gravitational force, falls back down. After falling and hitting to the bottom, the recycled fiber material is defibered, forming a fiber pulp mixture with water. A value of at least one parameter describing the defibration process or fiber pulp properties is measured on the basis of the drum pulper or the resultant fiber pulp mixture, and this value is used for controlling the rotation speed of the drum of the drum pulper. The invention also relates to a drum pulper implementing the method of the invention.

The invention provides a paper pulp quality control method and system of a high-concentration defibrination system. The method comprises the steps that the feeding spiral rotating speed, abrasive wheel clearance, dilution water flow, yield, mill load and paper pulp concentration of the high-concentration defibrination system are collected; a high-concentration defibrination system paper pulp quality control model is used for operation variable prediction; predicated operation variables are sent to an executing mechanism of the high-concentration defibrination system. The system comprises a data collecting unit, an operation variable prediction unit and an output paper pulp quality control unit. Based on high-concentration disc mill input and output relevant data measured by a sensor on a chemical mechanical pulping production line, an AIC criterion is combined to determine the order of a submodel, a submodel parameter is obtained through a forgetting factor least square algorithm, a mechanism model of the paper pulp quality freeness index is combined to build a Wiener model structure of the a high-concentration defibrination system, the quadratic performance index is optimized through a sequential quadratic programming algorithm, and the pulping output paper pulp quality index-freeness is effectively controlled.

An improvement to a mechanical refining system relates to an apparatus including three or more actuators (100) coupled to a stator (42) of the refining system, and a controller for independently operating the actuators. An improved method of refining permits adjustment of the overall width of a refining gap between refining elements mounted by the stator and a rotor as well as the trim of the refining elements relative to each other

A method for controlling the quality of pulp. Pulp produced by mechanical defibering of wood is screened to provide at least two fractions, of which the accept that has passed the screening phase is carried forward for use and the reject that has not passed the screening is removed from the screening phase. The consistency of the reject that is to be removed from the screening is measured and the consistency value thus obtained is used for controlling the defibrator to adjust the quality of the accept.

The present invention is directed to a process for the hot dispersing of a paper fiber stock that includes providing an aqueous paper fiber stock and pressing the aqueous fiber stock in a thickening device. In this manner, water is at least partially removed from the aqueous fiber stock to form a highly consistent paper fiber stock. The process further includes heating the highly consistent paper fiber stock, dispersing the heated highly consistent paper fiber stock with a disperser, determining a thermal energy consumed to heat the highly consistent paper fiber stock, and controlling a dewatering effect of the thickening device. The dewatering effect is increased with rising thermal energy consumption and is reduced with a falling thermal energy consumption. The instant abstract is neither intended to define the invention disclosed in this specification nor intended to limit the scope of the invention in any way.

The invention provides an automatic control system and method of knife feeding and retracting of a dual-disc refiner. The dual-disc refiner comprises a knife feeding speed reduction motor and a worm wheel and worm box. An output shaft of the knife feeding speed reduction motor is connected with a worm through a coupler. A coupler protecting cover is arranged on the periphery of the coupler. A counting marker is fixed to the coupler. A sensor corresponding to the counting marker in position is fixed to the coupler protecting cover. When the knife feeding speed reduction motor conducts rapid knife retracting, the sensor detects and records the rotating revolution N of the counting marker; when the knife feeding speed reduction motor conducts knife feeding, rapid feeding is conducted according to the revolution N stored in the last time of knife retracting, and the feeding revolution is (N-1); when knife feeding is conducted by (N-1) revolutions, rapid knife feeding is stopped and changedinto slow knife feeding; when main motor actual power collected by a power transmitter is equal to set power, knife feeding is stopped. The dual-disc refiner can conduct rapid knife feeding after being turned on, time is saved, energy consumption is reduced, the work efficiency of the device is improved, and the collision of abrasive discs of the dual-disc refiner can be prevented.

A sensor device for measuring distance between a stator and a rotor in a machine is of the magnetic type and is intended to be mounted in the stator in order to interact with an opposing surface on the rotor. A sensor body (10) can be moved axially in a housing (11) mounted in the stator by means of an operating mechanism (13) and has a stop (16) at a predetermined distance (e) from its end surface designed to interact with a corresponding stop (17) inside the housing. This distance (e) exceeds the distance (d) between the stop (17) in the hosing and the end of the sensor body (10) by a predetermined distance (c) when the sensor body is in its normal measuring position. These stops (16, 17) make possible a particularly accurate calibration of the sensor device.

A method is described for controlling a process section for thermo-mechanical pulp (TMP) refining. The process section has at least one first refiner having a plurality of sensors arranged in a predetermined position on a refiner plate of the at least one first refiner. The method comprises measuring, alternatively estimating, one or more process variables representing external states outside of the refiner Formula (I) for said process section and measuring, alternatively estimating, one or more values representing one or more internal states states Formula (II) inside said at least one first refiner, and calculating a change for said at least one manipulated variable (u 1 ) for said at least one refiner using said measurement of an internal state Formula (II) of said at least one refiner and a measurement of said one or more process external states Formula (I); for said process section by means of a mathematical process model.

A technique for latency removal which can be effected without introducing a significant lag time can advance analysis of pulp for feedback control thermo-mechanical pulp applications. The process for analyzing a pulp material includes: (a) collecting a representative sample of the pulp material, (b) adjusting the consistency of the sample to yield an adjusted pulp sample, (c) employing a disintegrator to release latency from the pulp that is in the adjusted pulp sample to form a pulp composition that is substantially free of latent properties, and (d) analyzing the pulp composition to measure at least one pulp quality.

A method is proposed for improving pulp quality at high production rates on conical disc refiners. It permits a reduction in refining intensity by enabling fibre residence time to increase by increasing consistency, while avoiding the problem of plate plugging normally associated with high discharge consistency. In practice, inlet consistency is increased by the in-feed dilution, flat zone dilution or both, but without allowing the discharge consistency to rise. Instead, the discharge consistency is controlled at a fixed optimum value by the addition of dilution water within the conical zone. The result is that residence time is increased, and refining intensity decreased, by raising the consistency in the inner region of the refining zone, while avoiding the plate plugging caused by excessive consistency in the outer region of the refining zone.

A transducer (10) for distance measurement, especially between a stator and a rotor in a refiner for paper pulp production, in which the transducer is of the magnetic type and has a tubular casing (17), the one end of which forms a measuring head (14), in which a measuring pole (15) is fitted in a holder (16) which is mounted in the end of the casing (17) and seals this. The holder (16), with a first portion (22) of its axial length, reaches beyond the end of the casing. This first portion (22) and the measuring pole (15) are intended to be able to be worn away to a smaller axial length during use of the transducer, whilst the length of the casing is maintained.

The present invention relates to a method and a system for controlling a refiner, grinder or the like for refining a product containing cellulose, such as pulp. A quality index specific to the product is provided and related to at least one predefined property of a slurry containing the cellulose product, or a finished product made of it. Control signals in response to the quality index is generated to achieve a desired value of the predetermined property, and at least one operating parameter of the refiner is set accordingly. The predefined property is either the tensile strength of said finished product or the Canadian Standard Freeness (CSF) of the slurry.