Pulp preparation control system for emergency broken paper of multi-layer white cardboard machine

Abstract

The utility model discloses a pulp preparation control system for emergency broken paper of a multilayer white cardboard machine, which comprises a surface layer pulp preparation pool, a core layer pulp preparation pool, a bottom layer pulp preparation pool, a wet damage tower and a dry damage tower, and all the pulp pools supply pulp to the paper machine through pipelines; a wet damage paper recovery pipeline is connected between the paper machine and the wet damage tower, and a dry damage paper recovery pipeline is connected between the paper machine and the dry damage tower; the bottom of the wet damage tower and the bottom of the dry damage tower are connected with a multi-disc concentrator, a broke concentration tank, a broke mill forebay and a broke mill which are used for treating mixed broke pulp and then conveying the broke pulp to the core layer pulp preparation tank; an emergency broken paper flow guide pipe is further arranged between an output channel formed by connecting the wet damage tower and the dry damage tower in parallel and the core layer pulp mixing pool; by means of the emergency broken paper flow guiding pipe, automatic guiding and flow guiding into the core layer pulp preparing pool in the abnormal paper breaking stage or the starting-up paper guiding stage are achieved, a core layer can completely use a wet damage tower and a dry damage tower to recycle pulp, the permissible duration of abnormal paper breaking or starting-up paper guiding of a paper machine is effectively prolonged, and rapid consumption of stored broken paper after successful paper guiding is achieved.

Description

[Technical field]

[0001] The utility model relates to a pulping technology for broken paper of a white cardboard machine, in particular to a pulping control system for emergency broken paper of a multi-layer white cardboard machine. [Background technology]

[0002] In the papermaking process, white cardboard is mainly composed of three layers: the surface layer, the core layer and the bottom layer. This is because different pulp layers can give composite white cardboard different properties. In the ordinary production process of white cardboard, after the wood pulp is crushed and refined, it enters the pulp pool corresponding to the surface layer, the core layer and the bottom layer respectively, and the finished paper roll is produced by the paper machine. Among them, the surface layer and the bottom layer use 100% fresh wood pulp, the core layer uses 65%-80% fresh wood pulp, and the damaged paper processing conveyor line is used to copy 20%-35% damaged paper.

[0003] However, when the paper machine is in the abnormal paper breaking or paper feeding stage, the surface layer, core layer and bottom layer pulp will all enter the wet damage tower and dry damage tower because the finished roll cannot be produced. As a result, when the wet damage tower and dry damage tower are full, the machine must be stopped for processing. After the liquid level of the wet damage tower and dry damage tower is reduced, the paper feeding can be started. The processing time after the wet damage tower and dry damage tower are full is often too long, which greatly reduces the production efficiency. In order to increase the allowable time for the paper machine to handle abnormal situations and start paper feeding, white cardboard machines often need to be equipped with large wet damage towers and dry damage towers, which greatly increases the equipment cost. [Contents of the utility model]

[0004] The utility model provides a pulp distribution control system for emergency broken paper of a multi-layer white cardboard machine, which realizes 100% use of the recovered pulp of the wet damaged paper tower and the dry damaged paper tower in the core layer during abnormal paper breaking or paper feeding stage at startup, so that the allowable time of abnormal paper breaking or paper feeding at startup of the paper machine is increased to 280%, the probability of overflow of the wet damaged paper tower and the dry damaged paper tower is reduced, and the rapid consumption of the broken paper stored in the wet damaged paper tower and the dry damaged paper tower is realized after the paper feeding is successful.

[0005] The technical solution adopted by the utility model to solve its technical problems is:

[0006] A pulp distribution control system for emergency broke paper of a multi-layer white cardboard machine, comprising a surface layer pulp distribution tank, a core layer pulp distribution tank, a bottom layer pulp distribution tank, a wet breakage tower and a dry breakage tower, wherein the surface layer pulp distribution tank, the core layer pulp distribution tank and the bottom layer pulp distribution tank supply pulp to a paper machine through a pipeline and process the pulp into rolls;

[0007] A wet damaged paper recovery pipeline is connected between the paper machine and the wet damaged paper tower, which is used to pump the damaged paper from the wire section and the press section into the wet damaged paper tower after pulping by the under-machine pulper when the paper machine is in an abnormal paper break or paper threading stage; and a dry damaged paper recovery pipeline is connected between the paper machine and the dry damaged paper tower, which is used to recover the damaged paper generated in the sizing section and subsequent sections into the dry damaged paper tower when the paper machine is in an abnormal paper break or paper threading stage when the paper machine is in an abnormal paper break or paper threading stage when the paper machine is in a startup;

[0008] The bottoms of the wet damaged tower and the dry damaged tower are connected with pipelines and at least one pulp pump to sequentially concentrate, screen, purify and refine the damaged paper pulp obtained by mixing wet damaged paper and dry damaged paper, and then transport it to the multi-disc thickener, damaged paper thickener, damaged paper pre-grinding tank and damaged paper mill in the core layer stock preparation tank again;

[0009] An emergency damaged paper guide pipe is also provided between the output channel in parallel of the wet damaged tower and the dry damaged tower and the core layer stock distribution pool, which utilizes the liquid level difference between the wet damaged tower, the dry damaged tower and the core layer stock distribution pool to automatically guide and drain the slurry in the wet damaged tower and the dry damaged tower to the core layer stock distribution pool when abnormal paper breakage or paper feeding is started, so as to extend the filling time.

[0010] Preferably, an automatic switch valve for controlling the on-off of the pipeline is provided at the emergency broken paper guide pipe near the wet broken paper tower and the dry broken paper tower in parallel, and a regulating valve and a flow meter are provided at the outlet end of the emergency broken paper guide pipe near the core layer pulp mixing tank.

[0011] Preferably, the emergency damaged paper guide pipe is also provided with a flushing water valve which is connected to an external water source to flush the pipe when it is not in use.

[0012] The beneficial effects of the utility model are:

[0013] Through the emergency damaged paper guide pipe between the output channel of the wet damaged tower and the dry damaged tower in parallel and the core layer pulp distribution pool, as well as the automatic switch valve for controlling the on-off of the pipeline set at the inlet of the emergency damaged paper guide pipe, and the regulating valve and flow meter set at the outlet end; when the paper breaks abnormally or the paper is started, the liquid level difference between the wet damaged tower, the dry damaged tower and the core layer pulp distribution pool is used, and the flow is calculated by the formula. Only the distribution ratio needs to be input to automatically calculate the distribution flow, and the opening of the outlet is automatically adjusted by the regulating valve to achieve stable control of the flow, and the pulp in the wet damaged tower and the dry damaged tower is automatically guided and drained through the emergency damaged paper guide pipe, which effectively reduces the liquid level and prolongs the filling time.

[0014] The utility model has the advantages of simple structure and low cost. When abnormal paper breakage or paper threading is caused during startup, 100% of the damaged paper mixed in the wet damaged tower and the dry damaged tower can be recycled in the core layer pulp mixing pool, thereby extending the filling time of the wet damaged tower and the dry damaged tower, effectively extending the allowable time of abnormal paper breakage or paper threading of the paper machine, reducing the downtime loss caused by the fullness of the wet damaged tower and the dry damaged tower, and realizing the rapid consumption of the damaged paper stored in the wet damaged tower and the dry damaged tower after successful paper threading.

Brief Description of the Drawings

[0015] Figure 1 It is a schematic diagram of the system principle of the utility model. [Specific implementation method]

[0016] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without making creative changes are within the scope of protection of the utility model.

[0017] A pulping control system for emergency broken paper of a multi-layer white cardboard machine, such as Figure 1 As shown, it includes a surface layer pulp preparation tank 1, a core layer pulp preparation tank 2, a bottom layer pulp preparation tank 3, a wet damaged paper tower 4 and a dry damaged paper tower 5. The surface layer pulp preparation tank 1, the core layer pulp preparation tank 2 and the bottom layer pulp preparation tank 3 supply pulp to a paper machine 6 for forming paper through pipelines and process the pulp into rolls; a wet damaged paper recovery pipeline 7 is connected between the paper machine 6 and the wet damaged paper tower 4, which is used for pumping the damaged paper of the wire part and the pressing part into the wet damaged paper tower 4 after pulping by the under-machine pulper when the paper machine is in an abnormal paper break or paper feeding stage when the paper machine is in an abnormal paper break or paper feeding stage when the paper machine is in a startup; a dry damaged paper recovery pipeline 8 is connected between the paper machine 6 and the dry damaged paper tower 5, which is used for recovering the damaged paper generated in the sizing part and the subsequent sections into the dry damaged paper tower 5 when the paper machine is in an abnormal paper break or paper feeding stage when the paper machine is in an startup; The bottom of the damaged paper tower 4 and the dry damaged paper tower 5 are connected with pipelines and multiple pulp pumps to sequentially concentrate, screen, purify and refine the damaged paper pulp obtained by mixing wet damaged paper and dry damaged paper, and then transport it to the core layer pulp distribution tank 2 again; an emergency damaged paper guide pipe 13 is also arranged between the parallel output channels of the wet damaged paper tower 4 and the dry damaged paper tower 5 and the core layer pulp distribution tank 2, which uses the liquid level difference between the wet damaged paper tower 4, the dry damaged paper tower 5 and the core layer pulp distribution tank 2 to automatically guide and drain the pulp in the wet damaged paper tower 4 and the dry damaged paper tower 5 to the core layer pulp distribution tank 2 to extend the filling time when abnormal paper breakage or paper feeding is started.

[0018] Continue as Figure 1As shown, an automatic switch valve 14 for controlling the on-off of the pipeline is arranged at the output channel of the emergency damaged paper guide pipe 13 near the parallel connection of the wet damaged tower 4 and the dry damaged tower 5, and a regulating valve 15 and a flow meter 16 are arranged at the outlet end of the emergency damaged paper guide pipe 13 near the core layer pulp distribution pool 2; when working, when abnormal paper breakage or paper feeding is started, the automatic switch valve 14 and the regulating valve 15 are opened, and the liquid level difference between the wet damaged tower 4, the dry damaged tower 5 and the core layer pulp distribution pool 2 is utilized, and self-flow is realized without external power, and the regulating valve 15 and the flow meter 16 are used to adjust the paper flow rate. 6. Interlock control of the feeding amount, in which the demand flow of the emergency broken paper guide pipe 13 is calculated by the formula. Only the mixing ratio needs to be input to automatically calculate the mixing flow. Through the deviation between the measured value and the calculated value of the flow meter 16, the outlet opening is automatically adjusted through the regulating valve 15 to achieve stable control of the flow; 100% recycling of the mixed broken paper in the wet damaged tower 4 and the dry damaged tower 5 in the core layer pulp pool is achieved, the filling time of the wet damaged tower 4 and the dry damaged tower 5 is extended, and the downtime loss caused by the filling of the wet damaged tower 4 and the dry damaged tower 5 is reduced.

[0019] Moreover, a flushing water valve (not shown) is also provided on the emergency broken paper guide pipe 13. When the emergency broken paper is disabled, the on-site flushing water valve is manually opened for a flushing time of 30s-120s, which effectively prevents the emergency broken paper pipe from being blocked.

[0020] The above-described embodiments are only preferred embodiments of the present invention and are not intended to limit the scope of implementation of the present invention. All equivalent changes made based on the shape, structure and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A pulping control system for emergency broken paper of a multi-layer white cardboard machine, characterized in that: It comprises a surface layer pulp distribution tank, a core layer pulp distribution tank, a bottom layer pulp distribution tank, a wet loss tower and a dry loss tower. The surface layer pulp distribution tank, the core layer pulp distribution tank and the bottom layer pulp distribution tank supply pulp to a paper machine through pipelines and process the pulp into rolls. A wet damaged paper recovery pipeline is connected between the paper machine and the wet damaged paper tower, which is used to pump the damaged paper from the wire section and the press section into the wet damaged paper tower after pulping by the under-machine pulper when the paper machine is in an abnormal paper break or paper threading stage; and a dry damaged paper recovery pipeline is connected between the paper machine and the dry damaged paper tower, which is used to recover the damaged paper generated in the sizing section and subsequent sections into the dry damaged paper tower when the paper machine is in an abnormal paper break or paper threading stage when the paper machine is in an abnormal paper break or paper threading stage when the paper machine is in a startup; The bottoms of the wet damaged tower and the dry damaged tower are connected with pipelines and at least one pulp pump to sequentially concentrate, screen, purify and refine the damaged paper pulp obtained by mixing wet damaged paper and dry damaged paper, and then transport it to the multi-disc thickener, damaged paper thickener, damaged paper pre-grinding tank and damaged paper mill in the core layer stock preparation tank again; An emergency damaged paper guide pipe is also provided between the output channel in parallel of the wet damaged tower and the dry damaged tower and the core layer stock distribution pool, which utilizes the liquid level difference between the wet damaged tower, the dry damaged tower and the core layer stock distribution pool to automatically guide and drain the slurry in the wet damaged tower and the dry damaged tower to the core layer stock distribution pool when abnormal paper breakage or paper feeding is started, so as to extend the filling time.

2. A pulping control system for emergency broken paper of a multi-layer white cardboard machine according to claim 1, characterized in that: An automatic switch valve for controlling the on-off of the pipeline is arranged near the wet damaged paper guide pipe and the dry damaged paper guide pipe in parallel, and a regulating valve and a flow meter are arranged near the outlet end of the core layer pulp distribution tank.

3. The pulping control system for emergency broken paper of a multi-layer white cardboard machine according to claim 1, characterized in that: The emergency damaged paper guide pipe is also provided with a flushing water valve which is connected to an external water source to flush the pipe when it is not in use.

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