摘要:
A method for controlling the water jet sharpening sequence of a pulp grinder is provided, wherein a high-pressure sharpening water jet is directed toward a surface of a pulpstone with a water sharpening apparatus. An actual quality value of the fiber pulp is determined for at least one variable, and a target quality value is defined for each of the at least one variable. The actual quality values and corresponding target quality values are transmitted to a control unit that includes an adjustment strategy set for controlling water sharpening of the pulpstone. According to the adjustment strategy, the treatment pressure and/or the treatment interval of the sharpening water jet is controlled relative to an error value between the target quality value and the actual quality value of the fiber pulp. An associated apparatus is also provided.
摘要:
A method for controlling the water jet sharpening sequence of a pulp grinder is provided, wherein a high-pressure sharpening water jet is directed toward a surface of a pulpstone with a water sharpening apparatus. An actual quality value of the fiber pulp is determined for at least one variable, and a target quality value is defined for each of the at least one variable. The actual quality values and corresponding target quality values are transmitted to a control unit that includes an adjustment strategy set for controlling water sharpening of the pulpstone. According to the adjustment strategy, the treatment pressure and/or the treatment interval of the sharpening water jet is controlled relative to an error value between the target quality value and the actual quality value of the fiber pulp. An associated apparatus is also provided.
摘要:
An apparatus for controlling the level and discharge of a suspension or slurry of ground wood in a mechanical wood pulp forming process is described. The apparatus includes, below a wood grinder, a trough in which a slurry of ground wood is formed. The ground wood slurry is passed through a discharge port, which is located near the trough bottom, into a conduit in which a valve is located. The valve is controlled by a slurry level sensor so as to maintain the slurry level at a desired level at least higher than the discharge port. A wood chip cutter is employed at the discharge port and is sized to minimize blockage and facilitate removal of the slurry from the trough. In one form of the invention an apparatus for pressurizing the housing enclosing the wood grinder is described and in another form an open housing structure is shown and described.
摘要:
Apparatus is disclosed for the distribution of logs into the supply shafts of a plurality of successive grinders from a conveyor line consisting of several belt, chain or other conveyors placed in succession and carrying the logs transversely thereon. The logs are passed from one conveyor to the next and distributed into supply shafts through gaps between the conveyors, which are automatically started for moving the logs on the conveyor line so as to fill the supply shafts. The equipment previously known and used for this purpose has several disadvantages, e.g. the need for sorting of the logs, unnecessary operation of the conveyors, overfilling of the line, etc. The present invention obviates these drawbacks in that the line is provided with sensors for sensing the height of the stack of logs on the conveyor line above each grinder supply shaft, at least two sensors being located above the level of the conveyors so as to control the conveyors adjacent to the shaft, so that they will be started, in motion either simultaneously or separately towards the supply shaft therebetween to ensure that there is always a sufficient supply of logs at the grinder.
摘要:
The disclosure concerns both a process and an apparatus for producing wood pulp. Wood to be pulped is fed into a housing where the wood is ground. The housing is pressurized above atmospheric pressure. Water at a temperature over 100.degree. C. is fed to the pressurized housing in the grinding zone. The wood pulp produced by grinding is collected and is conveyed through a worm conveyor which causes the water in the pulp to be removed therefrom, while the pulp and the water removed therefrom are maintained at elevated pressure. The water under pressure is returned to the grinding zone in the housing. The wood pulp is thereafter returned to atmospheric pressure. Various pressure lock devices for transmitting the wood pulp from being under pressure to atmospheric pressure are disclosed including a nozzle, a pressure lock device, a hydrocyclone and/or a disc refiner.