Automatic sludge discharge control method for filter press

Abstract

The invention discloses an automatic sludge discharge control method for a filter press, which comprises the following steps: S1, after the filter press enters a sludge discharge process, starting a detection system, acquiring an image of the surface of a filter plate of the filter press by a scanning end of the detection system, and transmitting the image to a control end of the detection system; s2, the control end of the detection system processes the obtained image to obtain information about whether a mud cake on the surface of the filter plate falls off or not, and the mud cake information is transmitted to a filter press control system; s3, the filter press control system controls whether the auxiliary mud unloading device operates or not according to the mud cake information on the surface of the filter plate. The filter press has the characteristics of simple principle, convenience in operation, high sludge unloading efficiency and the like, realizes full-automatic work, and does not need manual field work.

Description

Technical Field

[0001] The invention relates to the technical field of sludge treatment, and in particular to an automatic sludge unloading control method for a filter press. Background Art

[0002] The filter press is a solid-liquid separation equipment in the sludge treatment industry. It achieves mud-water separation through filter cloth and filter plate under extrusion to reduce the moisture content of sludge. Among them, some sticky mud cakes will not fall off naturally during the mud unloading process of the filter press, and manual mud shoveling or other auxiliary mud unloading devices are required to help the filter press unload mud. In recent years, the auxiliary mud unloading device of the filter press has shown a blowout development, and various auxiliary mud unloading devices have been used; after the filter press uses some auxiliary mud unloading devices, although it can help the filter press unload mud, it also reduces the working efficiency of the filter press.

[0003] The automatic mud unloading device of the filter press has no corresponding detection system or method during the mud unloading process, and the auxiliary mud unloading device can only unload mud once for each filter plate without distinction. The existing technology has the following defects: The filter press takes a long time to unload mud. In actual use, the filter press has a certain natural shedding rate of mud cake: during the unloading process, after the filter plate is pulled apart, the mud cake can fall naturally without the auxiliary mud unloading device working. The natural falling rate of the mud cake is related to the mud quality of the mud cake and the use time of the filter cloth. Generally, the natural falling rate of the mud cake is between 10% and 99%. If each filter plate needs the auxiliary mud unloading device to work once during the unloading process (when the auxiliary mud unloading device is working, the filter press will suspend the plate pulling action or the hook-pulling filter plate device is in a suspended state), the overall unloading time of the filter press will be longer.

[0004] The mud unloading effect cannot be automatically determined, and the batch processing capacity of the filter press is low. Although most filter presses are currently equipped with auxiliary mud unloading devices, the mud unloading effect of the auxiliary mud unloading device is not stable, which has a lot to do with the use time of the filter cloth and the mud properties. Generally, the longer the filter cloth is used, the worse the filtration performance will be, the lower the mud cake drop rate will be, and the lower the mud unloading rate of the filter press will be. At present, the auxiliary mud unloading device can only mechanically work once on the same filter plate, and there is no way to automatically detect the mud unloading effect. If the mud cake on the filter plate still does not fall off after the auxiliary mud unloading device works, the mud cake will occupy the chamber space of the filter plate, resulting in a reduction in the processing capacity of the next batch of filter presses and a reduction in the production efficiency of the filter press. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide an automatic mud unloading control method for a filter press with simple principle, convenient operation and high mud unloading efficiency in view of the deficiencies in the prior art.

[0006] In order to solve the above technical problems, the technical solution adopted by the present invention is: A filter press automatic mud unloading control method comprises the following steps: Step S1, when the filter press enters the mud unloading process, the detection system is started, and the scanning end of the detection system obtains the image of the filter plate surface of the filter press and transmits it to the control end of the detection system; Step S2, the control end of the detection system processes the acquired image to obtain information on whether the mud cake on the surface of the filter plate has fallen off, and transmits the mud cake information to the filter press control system; Step S3: The filter press control system controls whether the auxiliary mud unloading device is running according to the mud cake information on the filter plate surface. As a further improvement of the present invention, in step S1, the scanning end of the detection system moves synchronously with the plate pulling device of the hook-pulled filter press filter plate during the mud unloading process, and moves with the pulled filter plate. When the filter plate is pulled open, it starts to scan the filter plate to obtain an image of the filter plate surface. As a further improvement of the present invention, the scanning end of the detection system scans the front, side and back of the filter plate to obtain image information of the filter plate height C, filter plate width D and total thickness b of the filter plate and mud cake, and transmits the image information to the control end of the detection system for processing and modeling to form a 3D image of the filter plate. As a further improvement of the present invention, the control end of the detection system divides the entire filter plate into N areas according to the 3D image of the filter plate, then the total area S of the entire filter plate = s1+s2+s3+s4+......+ sN; the total thickness of the filter plate and the mud cake corresponding to each area are b1, b2, b3, b4,..., bN respectively; then the total average thickness of the filter plate and the mud cake B = (b1+b2+b3+b4+......+bN) / N. As a further improvement of the present invention, the control end of the detection system compares the calculated total average thickness B of the filter plate and the mud cake with the designed thickness A of the filter plate. If B≤A, it indicates that the mud cake on the surface of the filter plate has fallen off, the auxiliary mud unloading device does not work, and the filter press control system controls the plate pulling device to continue pulling the plate to unload the mud. As a further improvement of the present invention, the control end of the detection system compares the calculated total average thickness B of the filter plate and mud cake with the designed thickness A of the filter plate. If B>A, it indicates that the mud cake on the surface of the filter plate has not fallen off, and the filter press control system controls the auxiliary mud unloading device to work once. After the auxiliary mud unloading device finishes working once, the detection system scans again to obtain the mud cake information; if the mud cake still has not fallen off, the auxiliary mud unloading device works again; if the mud cake falls off, the auxiliary mud unloading device stops working, and the filter press control system controls the plate pulling device to continue pulling the plate to unload the mud. As a further improvement of the present invention, when the auxiliary mud unloading device works on the same filter plate for a preset number of times, the plate pulling device continues to pull the plate to unload mud regardless of whether the mud cake falls off, and the filter press control system alarms and records. As a further improvement of the present invention, the filter press control system adopts a PLC control system. As a further improvement of the present invention, the scanning end of the detection system adopts a camera or an array camera or a camera combined with an infrared detector.

[0007] Compared with the prior art, the advantages of the present invention are: The automatic mud unloading control method for the filter press of the present invention can identify whether there is mud cake on the filter plate of the filter press through the detection system. When the filter press control system receives information that there is no mud cake on the filter plate, the filter press control system controls the auxiliary mud unloading device to directly skip the auxiliary mud unloading step and continue the plate pulling mud unloading step, which effectively saves mud unloading time and improves the mud unloading efficiency of the filter press. If the detection system identifies that the mud cake on the filter plate does not fall off during the mud unloading process, the filter press control system can control the auxiliary mud unloading device to work again to make the mud cake fall off the filter plate, which significantly improves the mud unloading rate of the filter press. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 It is a schematic diagram of the process of automatic mud unloading control of the filter press in a specific embodiment of the present invention; Figure 2 It is a schematic diagram of the composition of a control system in a specific embodiment of the present invention; Figure 3 It is a working principle diagram of the detection system in a specific embodiment of the present invention; Figure 4 It is a front view schematic diagram of a filter plate of a filter press in a specific embodiment of the present invention; Figure 5 It is a side view of a filter plate of a filter press in a specific embodiment of the present invention.

[0009] Legend: 1. Front of filter plate; 2. Side of filter plate; 3. Back of filter plate; 4. Center hole of filter plate; 5. Filter press hole. DETAILED DESCRIPTION

[0010] The present invention is further described below in conjunction with the accompanying drawings and specific preferred embodiments, but the protection scope of the present invention is not limited thereby.

[0011] In the description of the present invention, it should be understood that the terms "side", "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0012] In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or suggesting relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "multiple" means two or more, unless otherwise clearly and specifically defined.

[0013] Example like Figure 1 , Figure 2 and Figure 3 As shown, the automatic mud unloading control method of the filter press of the present invention comprises the following steps: Step S1, when the filter press enters the mud unloading process, the detection system is started, and the scanning end of the detection system obtains the image of the surface of the filter plate of the filter press and transmits it to the control end of the detection system.

[0014] Step S2: The CPU control end of the detection system processes the acquired image to obtain information on whether the mud cake on the surface of the filter plate has fallen off, and transmits the mud cake information to the filter press control system.

[0015] Step S3: The filter press control system controls whether the auxiliary mud unloading device is running according to the mud cake information on the filter plate surface. The detection system is linked with the filter press control system to accurately control the start and stop of the auxiliary mud unloading device, thereby increasing the mud cake drop rate and thus improving the mud unloading efficiency and production efficiency of the filter press.

[0016] In this embodiment, the filter press control system adopts a PLC control system, which has the characteristics of simple principle, convenient operation and precise control. The scanning end of the detection system can use an image forming device such as a camera or an array camera or a camera combined with an infrared detector to accurately obtain the key parameters of the filter plate surface.

[0017] In this embodiment, the detection system can identify whether there is mud cake on the filter plate of the filter press. When the filter press control system receives information that there is no mud cake on the filter plate, the filter press control system controls the auxiliary mud unloading device to directly skip the auxiliary mud unloading step and continue the plate pulling mud unloading step, which effectively saves mud unloading time and improves the mud unloading efficiency of the filter press. If the detection system identifies that the mud cake on the filter plate does not fall off during the mud unloading process, the filter press control system can control the auxiliary mud unloading device to work again to make the mud cake fall from the filter plate, which significantly improves the mud unloading rate of the filter press.

[0018] In step S1 of this embodiment, the scanning end of the detection system moves synchronously with the plate pulling device of the hook-pulling filter press filter plate during the mud unloading process, and moves with the pulled filter plate. The filter plate starts to be scanned at the moment the filter plate is pulled open to obtain an image of the filter plate surface. like Figure 4 and Figure 5 As shown, a filter plate center hole 4 is provided in the center of the filter plate, and filtrate holes 5 are provided around the filter plate. The scanning end of the detection system scans the front side 1, the side side 2 and the back side 3 of the filter plate to obtain key image parameter information such as the filter plate height C, the filter plate width D, and the total thickness b of the filter plate and the mud cake, and transmits the image information to the control end of the detection system for processing and modeling to form a 3D image of the filter plate.

[0019] The control end of the detection system divides the entire filter plate into N areas according to the 3D image of the filter plate. The total area of ​​the entire filter plate S = s1+s2+s3+s4+......+ sN; the total thickness of the filter plate and mud cake corresponding to each area are b1, b2, b3, b4,..., bN respectively; the total average thickness of the filter plate and mud cake B = (b1+b2+b3+b4+......+bN) / N.

[0020] The control end of the detection system compares the calculated total average thickness B of the filter plate and mud cake with the designed thickness A of the filter plate. If B≤A, it indicates that the mud cake on the surface of the filter plate has fallen off. The control end of the detection system sends corresponding instructions to the filter press control system, and the auxiliary mud unloading device does not work. The filter press control system controls the plate pulling equipment to continue pulling the plate to unload the mud.

[0021] If B>A, it means that the mud cake on the surface of the filter plate has not fallen off. The control end of the detection system sends a corresponding instruction to the filter press control system. The filter press control system controls the auxiliary mud unloading device to work once. After the auxiliary mud unloading device finishes working once, the detection system scans again to obtain the mud cake information; if the mud cake still has not fallen off, the auxiliary mud unloading device will work again; if the mud cake falls off, the auxiliary mud unloading device stops working, and the filter press control system controls the plate pulling device to continue pulling the plate to unload the mud.

[0022] When the auxiliary mud unloading device works on the same filter plate for a preset number of times, for example, twice, the specific number of repetitions can be set according to the actual sludge quality. After the auxiliary mud unloading device works twice, regardless of whether the mud cake falls off, the plate pulling device continues to pull the plate to unload mud, and the filter press control system alarms and records.

[0023] In other embodiments, parameters such as the design thickness A of the filter plate and the number N of regions divided by the filter plate may be adjusted according to actual site conditions.

[0024] The above is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A filter press automatic mud unloading control method, characterized in that: The following steps are involved: Step S1, when the filter press enters the mud unloading process, the detection system is started, and the scanning end of the detection system obtains the image of the filter plate surface of the filter press and transmits it to the control end of the detection system; Step S2, the control end of the detection system processes the acquired image to obtain information on whether the mud cake on the surface of the filter plate has fallen off, and transmits the mud cake information to the filter press control system; Step S3: The filter press control system controls whether the auxiliary mud unloading device is running according to the mud cake information on the filter plate surface.

2. The automatic mud unloading control method of the filter press according to claim 1, characterized in that: In step S1, the scanning end of the detection system moves synchronously with the plate pulling device of the hook-pulling filter press filter plate during the mud unloading process, and moves following the pulled filter plate. When the filter plate is pulled open, it starts to scan the filter plate to obtain an image of the filter plate surface.

3. The automatic mud unloading control method of the filter press according to claim 2 is characterized in that: The scanning end of the detection system scans the front side (1), the side side (2) and the back side (3) of the filter plate to obtain image information of the filter plate height C, the filter plate width D and the total thickness b of the filter plate and the mud cake, and transmits the image information to the control end of the detection system for processing and modeling to form a 3D image of the filter plate.

4. The automatic mud unloading control method for a filter press according to claim 3, characterized in that: The control end of the detection system divides the entire filter plate into N areas according to the 3D image of the filter plate. The total area of ​​the entire filter plate S = s1+s2+s3+s4+......+ sN; the total thickness of the filter plate and mud cake corresponding to each area are b1, b2, b3, b4,..., bN respectively; the total average thickness of the filter plate and mud cake B = (b1+b2+b3+b4+......+bN) / N.

5. The automatic mud unloading control method of the filter press according to claim 4, characterized in that: The control end of the detection system compares the calculated total average thickness B of the filter plate and mud cake with the designed thickness A of the filter plate. If B≤A, it indicates that the mud cake on the surface of the filter plate has fallen off, the auxiliary mud unloading device does not work, and the filter press control system controls the plate pulling device to continue pulling the plate to unload the mud.

6. The automatic mud unloading control method of the filter press according to claim 4, characterized in that: The control end of the detection system compares the calculated total average thickness B of the filter plate and mud cake with the designed thickness A of the filter plate. If B>A, it indicates that the mud cake on the surface of the filter plate has not fallen off. The filter press control system controls the auxiliary mud unloading device to work once. After the auxiliary mud unloading device finishes working once, the detection system scans again to obtain the mud cake information; if the mud cake still has not fallen off, the auxiliary mud unloading device works again; if the mud cake falls off, the auxiliary mud unloading device stops working, and the filter press control system controls the plate pulling device to continue pulling the plate to unload the mud.

7. The automatic mud unloading control method of the filter press according to claim 6, characterized in that: When the auxiliary mud unloading device has worked on the same filter plate for a preset number of times, the plate pulling device will continue to pull the plate to unload mud regardless of whether the mud cake falls off or not, and the filter press control system will alarm and record.

8. The automatic mud unloading control method for a filter press according to any one of claims 1 to 7, characterized in that: The filter press control system adopts a PLC control system.

9. The automatic mud unloading control method for a filter press according to any one of claims 1 to 7, characterized in that: The scanning end of the detection system adopts a camera or an array camera or a camera combined with an infrared detector.

Images