CA1125077A
Expired / Lapsed
CA
⏱️ 0.0 years remaining
Procedure and apparatus for preparing groundwood mechanically from wood chips
Assignee: Stora Enso Oyj
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Filing: 1980-03-19
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Granted: 1982-06-08
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Expires: 2000-03-19
Abstract
Abstract ABSTRACT OF THE DISCLOSURE A process for mechanically producing groundwood from wood chips, the wood chips being treated, after pre-heating under pressure in a steaming chamber, in two steps in disk grinders operating under pressure, these disk grinders having feeding means of enclosed construction. The groundwood coming from the first stepdisk grinder is conducted under the pressure of the steam generated in the blade interval of the grinder to the feeding means of the second step disk grinder. The transport of the groundwood is performed along a pipeline which is directly connected to the feeding means of the second step disk grinder. In said feeding means feeding problems arising from floating of the groundwood in the steam flow discharging from the second disk grinder against the ground-wood flow is eliminated by feeding into the pipeline water or a chemical solution, which increases to the specific gravity of the groundwood.
Inventors
- 👤 Erkki Valkama
- 👤 Rainer Skinnar
- 👤 Kauko Tiainen
- 👤 Pentti Hyytiainen
Bibliographic Details
Application Number
—
Jurisdiction
CA
Data Source
google_patents
Last Synchronized
2026-10-30 17:12
CPC Classifications
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Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
174 words
In a process for mechanically producing groundwood from wood chips, in which the wood chips, after pre-heating under pressure in a steaming chamber, are treated in first and second sequential steps in disk grinders under pressure, said disk grinders having feeding means of enclosed construction, the groundwood from disk grinder of the first step being conducted, under the pressure of the steam generated in the blade interval of the grinder of the first step to the feeding means of the disk grinder of the second step, the improvement in which the transport of the groundwood is effected along a pipeline which is directly connected to the feeding means of the disk grinder of the second step, into which pipeline water or a chemical solution, which increases the specific gravity of the groundwood is fed whereby any problems in the feeding means of the disk grinder of the second step due to floating of the groundwood in the steam flow discharging from the disk grinder of the second step against the groundwood flow is avoided.
Claim 2
Dependent Claim
174 words
In a process for mechanically producing groundwood from wood chips, in which the wood chips, after pre-heating under pressure in a steaming chamber, are treated in first and second sequential steps in disk grinders under pressure, said disk grinders having feeding means of enclosed construction, the groundwood from disk grinder of the first step being conducted, under the pressure of the steam generated in the blade interval of the grinder of the first step to the feeding means of the disk grinder of the second step, the improvement in which the transport of the groundwood is effected along a pipeline which is directly connected to the feeding means of the disk grinder of the second step, into which pipeline water or a chemical solution, which increases the specific gravity of the groundwood is fed whereby any problems in the feeding means of the disk grinder of the second step due to floating of the groundwood in the steam flow discharging from the disk grinder of the second step against the groundwood flow is avoided.
Claim 3
Dependent Claim
64 words
A process according to claim 1, in which the addi-tion of water of chemicals is made upstream of a push valve in the pipeline, by which valve the steam pressure in the disk grinder of the second step is regulated to be lower than the pressure prevailing in the disk grinder of the first step by the amount of flow resistance in the pipeline.
Claim 4
Dependent Claim
22 words
A process according to claim 1, in which the first step is effected by at least two disk grinders connected in parallel.
Claim 5
Independent Claim
137 words
An apparatus for mechanically producing groundwood from wood chips comprising at least one first step disk grinder, a first feeding means for feeding pre-heated wood chips from a steam chamber to said at least one first step disk grinder; said first feeding means being adapted to operate into the pres-sure prevailing in the steam chamber; a second step disk grinder, second feeding means for feeding groundwood for the at least one first step grinder to the second step grinder into the pressure of steam generated in the at least one first step disc grinder; said second feeding means being of a closed structure, the at least one first step disk grinder having an output connector connected by a pipeline with the second feeding means whereby the highest steam pressure is obtained in the second step disk grinder.
Claim 6
Independent Claim
137 words
An apparatus for mechanically producing groundwood from wood chips comprising at least one first step disk grinder, a first feeding means for feeding pre-heated wood chips from a steam chamber to said at least one first step disk grinder; said first feeding means being adapted to operate into the pres-sure prevailing in the steam chamber; a second step disk grinder, second feeding means for feeding groundwood for the at least one first step grinder to the second step grinder into the pressure of steam generated in the at least one first step disc grinder; said second feeding means being of a closed structure, the at least one first step disk grinder having an output connector connected by a pipeline with the second feeding means whereby the highest steam pressure is obtained in the second step disk grinder.
Claim 7
Dependent Claim
35 words
An apparatus according to claim 4, in which there are provided a plurality of first step disk grinders connected in parallel and connected by means of a common pipeline to the second step disk grinder.
Claim 8
Dependent Claim
59 words
An apparatus according to claim 4, in which in the pipeline between the first and second step grinders, immediately downstream the outlet connector, there is provided means for introducing water or a chemical solution, its quantity being regulated by means of a valve so that the grinding consistency in the second step disk grinder is between 20 and 30%.
Claim 9
Dependent Claim
65 words
An apparatus according to claim 4, 5 or 6, in which a pipeline is provided between the first and second step grinders which contains a push valve for regulation of the pressure on the input side of the second step disk grinder to be lower than the pressure prevailing in the first step disk grinder by the amount of the flow resistances in said pipeline.
References Cited (Backward Citations)
No citation records indexed.
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