Method for rapidly detecting end of feeding of filter press

Abstract

A method for rapidly detecting the end of feeding of a filter press belongs to the technical field of filter presses and comprises the following steps: S1, obtaining a first judgment condition for the end of feeding of the filter press according to historical duration data of a time period from opening to closing of a feeding pump of the filter press; and S2, according to the flow data of the filtrate water of the filter press, obtaining a second judgment condition for finishing feeding of the filter press. S3, data of the first judgment condition and the second judgment condition serve as reference values for judging that feeding of the filter press is finished and are transmitted to a PLC, and when the filter press meets the two judgment conditions at the same time, it is indicated that feeding of the filter press is finished. According to the method for rapidly detecting the feeding end of the filter press, the historical feeding end duration and the filtrate water flow of the filter press are selected as main reference indexes of the feeding end opportunity of the filter press, manual judgment is not needed, the judgment efficiency and accuracy can be effectively improved, the production benefit can be improved, and the method is suitable for popularization.

Description

Technical Field

[0001] The present invention relates to the technical field of filter presses, and particularly to a method for quickly detecting the end of the feed of a filter press. Background Art

[0002] A filter press is a commonly used solid-liquid separation device. It uses a special filtering medium to apply a certain pressure to an object, so that the liquid seeps out, thereby realizing solid-liquid separation. According to different structures and functions, filter presses can be divided into various types, such as plate and frame filter presses, chamber filter presses, vertical filter presses, and belt filter presses, etc. Among them, plate and frame filter presses and chamber filter presses are two relatively common types.

[0003] The working principle of a filter press is mainly based on pressure filtration technology. The filter plates are tightened by a pressing device to form a closed filter chamber, and then the material to be treated is pumped into the filter chamber by a feed pump. Under the action of pressure, the liquid penetrates through the filter cloth and is discharged, while the solid particles are retained on the surface of the filter cloth to form a filter cake. The specific process can be divided into the following four main stages: pre-press stage, filtration stage, backwash stage, and pressure release stage.

[0004] Due to its efficient and reliable solid-liquid separation performance, filter presses have been widely used in many industries. The specific application fields include but are not limited to: industrial wastewater treatment, chemical raw material recovery, mineral processing, and food and pharmaceutical industries. Although filter presses, as an important solid-liquid separation device, play a key role in many industries, there are still the following deficiencies in the actual use process: the existing methods commonly used to judge the end of the feed of a filter press mainly rely on workers for manual judgment, with a high degree of dependence on workers, low work efficiency and accuracy, thus affecting the production efficiency of the filter press. Summary of the Invention

[0005] The purpose of the present invention is to overcome the deficiencies in the prior art, such as high dependence on workers, low work efficiency and accuracy, and provide a method for quickly detecting the end of the feed of a filter press. This method selects the historical feed end duration and filtrate water flow rate of the filter press as the main reference indicators for the timing of the end of the feed of the filter press. Without relying on manual judgment, it can effectively improve the judgment efficiency and accuracy, is beneficial to improving the production efficiency, and is suitable for popularization.

[0006] The present invention is realized by the following technical solutions: A method for quickly detecting the end of the feed of a filter press, comprising the following steps: S1. The feed pump of the filter press is signal-connected to the PLC sub-station in the filter press workshop to operate the opening and closing of the feed pump of the filter press. Meanwhile, the historical duration data of the filter press feed pump from the start to the stop is collected multiple times through the PLC, and the abnormal data in the historical duration data is removed, and then the average value is taken; this average value is the historical feed end duration threshold of the filter press, and this duration threshold is used as the first condition for judging the end of the filter press feed.

[0007] S2. A measurement system signal-connected to the PLC sub-station in the filter press workshop is installed on the filter press. The measurement system is used to measure the flow rate data of the filtrate water of the filter press. The flow rate data of the filtrate water of the filter press is collected through the PLC, and then the flow rate value of the filtrate water at the end of the historical feed of the filter press is determined through the flow rate data; this flow rate value is the flow rate threshold, and this flow rate threshold is used as the second condition for judging the end of the filter press feed.

[0008] S3. The data of the first condition for judging the end of the filter press feed and the second condition for judging the end of the filter press feed are used as the reference values for judging the end of the filter press feed and transmitted to the PLC. When the filter press meets both judgment conditions at the same time, it means that the filter press feed is ended.

[0009] This method mainly selects the historical feed end duration of the filter press and the flow rate of the filtrate water as the main reference indicators for the timing of the filter press to end the feeding (complete the dehydration process). By setting the flow rate threshold of the filtrate water and supplemented by monitoring the working process of the filter press, they are used as the main judgment conditions for the timing of the filter press to end the feeding. That is, the historical feed end duration threshold of the filter press is used as the first condition for judging the end of the filter press feed, and the flow rate threshold of the filtrate water is used as the second condition for judging the end of the filter press feed. That is to say, the feeding duration of the filter press and the flow rate of the filtrate water are jointly judged. When both conditions are met, the PLC judges that the filter press can stop feeding and enter the next operation process, otherwise the filter press continues to feed.

[0010] A further improvement of the present invention is that in step S1, the opening and closing of the feed pump of the filter press are manually operated. Manual operation has better flexibility and is beneficial for workers to collect the historical duration data.

[0011] A further improvement of the present invention is that the abnormal data includes the longest historical duration data and the shortest historical duration data. The selection of the above abnormal data can further improve the accuracy of the average value.

[0012] A further improvement of the present invention is that in step S2, the measurement system includes a filter press filtrate water tank and a water receiving tank arranged below the filter press filtrate water tank. The filter press filtrate water tank is connected with a drain branch pipe for leading out the filtrate water, and the drain branch pipe is connected to the top of the water receiving tank; the bottom of the water receiving tank is connected with a conveying branch pipe, the conveying branch pipe is connected with a circulation water tank, and an electromagnetic flowmeter for measuring the flow data of the filter press filtrate water is connected to the central position of the conveying branch pipe. The electromagnetic flowmeter is signal-connected to the PLC sub-station in the filter press workshop. The overall structure of the measurement system is simple, easy to assemble and convenient to operate. Through the measurement system, workers can better measure the flow data of the filter press filtrate water, ensuring the accuracy of the flow data.

[0013] A further improvement of the present invention is that a connection hole is provided at the central position of the bottom of the filter press filtrate water tank, and the filter press filtrate water tank is connected with the drain branch pipe through the connection hole. Through the above design, the assembly difficulty can be further reduced.

[0014] A further improvement of the present invention is that a cross-flow guide plate is arranged inside the water receiving tank, and the guide plate is used to guide the filtrate water introduced into the water receiving tank, so that the filtrate water can flow smoothly to the conveying branch pipe. Through the design of the above guide plate, the conveying fluency of the filtrate water can be further improved.

[0015] A further improvement of the present invention is that the conveying branch pipe is vertically connected to the water receiving tank and the circulation water tank, and the conveying branch pipe is vertically connected to the electromagnetic flowmeter through a vertical branch pipe. Through the above vertical connection design, it is ensured that the electromagnetic flowmeter is always full-pipe measured, thus ensuring that there is no overflow of filtrate water in the whole measurement system.

[0016] A further improvement of the present invention is that the drain branch pipe, the conveying branch pipe and the vertical branch pipe are all made of DN50 stainless steel pipes. The DN50 stainless steel pipes are convenient to obtain materials, which can further reduce the assembly difficulty.

[0017] The beneficial effect of the present invention is that this method mainly selects the historical feeding end duration of the filter press and the filtrate water flow rate as the main reference indicators for the filter press to end the feeding time (complete the dehydration process). By setting the filtrate water flow rate threshold and supplemented by monitoring the working process of the filter press, it is used as the main judgment condition for the filter press to end the feeding time. That is, taking the historical feeding end duration threshold of the filter press as the first judgment condition for the filter press to end the feeding, and taking the filtrate water flow rate threshold as the second judgment condition for the filter press to end the feeding. That is, jointly judging the feeding duration of the filter press and the filtrate water flow rate. When both conditions are met, the PLC judges that the filter press can stop feeding and enter the next operation process, otherwise the filter press continues to feed. It can be seen that by using this method, it is no longer necessary to rely on manual judgment, effectively improving the judgment efficiency and accuracy, which is beneficial to improving production efficiency. Description of the Drawings

[0018] To more clearly illustrate the technical solution of the present invention, the accompanying drawings required for description will be briefly introduced below. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can be obtained based on these drawings.

[0019] Figure 1 It is a judgment logic demonstration diagram of a specific embodiment of the present invention.

[0020] Figure 2 It is a structural schematic diagram of the measurement system of a specific embodiment of the present invention.

[0021] In the figure: 1, filter press filtrate water tank; 101, connection hole; 2, water receiving tank; 3, drain branch pipe; 4, conveying branch pipe; 401, vertical branch pipe; 5, circulation water tank; 6, electromagnetic flowmeter; 7, filter press workshop PLC substation; 8, baffle plate. Specific embodiments

[0022] To make the objectives, features, and advantages of the present invention more obvious and understandable, the technical solutions in the present invention will be clearly and completely described below in conjunction with the accompanying drawings in this specific embodiment. Obviously, the embodiments described below are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments in this patent, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of this patent.

[0023] Embodiment 1, now referring to Figure 1 , the description is as follows: A method for quickly detecting the end of the filter press feeding of the present invention includes the following steps: S1. The filter press feed pump is signal-connected to the filter press workshop PLC substation 7. Manually operate the opening and closing of the filter press feed pump, and at the same time, collect the historical duration data of the filter press feed pump from the start to the end through the PLC multiple times. Eliminate the abnormal data in the historical duration data. The abnormal data includes the longest historical duration data and the shortest historical duration data. After eliminating the abnormal data, take the average value; the average value is the historical filter press feeding end duration threshold, and this duration threshold is used as the first judgment condition for the end of the filter press feeding.

[0024] S2. A measurement system signal-connected to the filter press workshop PLC substation 7 is installed on the filter press. The measurement system is used to measure the flow data of the filter press filtrate water. Collect the flow data of the filter press filtrate water through the PLC, and then determine the flow value of the filter press filtrate water at the end of the historical feeding through the flow data; the flow value is the flow threshold, and this flow threshold is used as the second judgment condition for the end of the filter press feeding.

[0025] S3. Take the data of the first and second judging conditions for the end of the filter press feeding as the reference value for judging the end of the filter press feeding and transmit it to the PLC. When the filter press meets both judging conditions simultaneously, it indicates that the filter press feeding is over.

[0026] Combined with the existing coal slime pressing process, the state change of the filtrate water of the filter press can directly reflect the change of coal slime pressing during the pressing process. Usually, within one pressing cycle, the filtrate water follows the change of clear (clean water) - turbid (mixed with fine mud) - clear again (clean water), representing the three stages of the initial feeding stage - the middle feeding stage - the end of feeding respectively. At the same time, the flow rate of the filtrate water also follows the basic law of small amount (clean water) - large amount (mixed with fine mud) - small amount again until the water does not drip in a line (clean water), which can also represent the three stages of the initial feeding stage - the middle feeding stage - the end of feeding.

[0027] Based on the above two basic laws, this method mainly selects the historical feeding end duration of the filter press and the flow rate of the filtrate water as the main reference indicators for the timing of the filter press to end feeding (complete the dehydration process). By setting the threshold value of the filtrate water flow rate and supplemented by monitoring the working process of the filter press, it serves as the main judging condition for the timing of the filter press to end feeding. That is, taking the historical feeding end duration threshold of the filter press as the first judging condition for the end of the filter press feeding, and taking the flow rate threshold of the filtrate water as the second judging condition for the end of the filter press feeding. That is to say, jointly judge the feeding duration of the filter press and the flow rate of the filtrate water. When both conditions are met, the PLC judges that the filter press can stop feeding and enter the next operation process. Otherwise, the filter press continues to feed.

[0028] Example 2. On the basis of Example 1, referring to Figure 2 , the measuring system includes a filter press filtrate water tank 1 and a water receiving tank 2 arranged below the filter press filtrate water tank 1. A connection hole 101 is opened at the central position of the bottom of the filter press filtrate water tank 1. The filter press filtrate water tank 1 is connected with a drain branch pipe 3 for leading out the filtrate water through the connection hole 101. The drain branch pipe 3 is made of DN50 stainless steel pipe, and both ends of the drain branch pipe 3 are connected with the connection hole 101 and the top of the water receiving tank 2 respectively by welding.

[0029] The bottom of the water receiving tank 2 is connected with a conveying branch pipe 4. The conveying branch pipe 4 is made of DN50 stainless steel pipe. One end of the conveying branch pipe 4 is connected with the water receiving tank 2 by welding, and the other end is connected with a circulating water tank 5. And an electromagnetic flowmeter 6 for measuring the flow rate data of the filter press filtrate water is connected to the central position of the conveying branch pipe 4. The electromagnetic flowmeter 6 is signal-connected to the PLC sub-station 7 in the filter press workshop.

[0030] The overall structure of the measurement system is simple, facilitating assembly and operation. Through the measurement system, workers can better measure the flow data of the filtrate water of the filter press, ensuring the accuracy of the flow data.

[0031] Specifically, a crosswise deflector plate 8 is arranged inside the water receiving tank 2. The deflector plate 8 is used to deflect the filtrate water introduced into the inside of the water receiving tank 2, so that the filtrate water can flow smoothly to the delivery branch pipe 4. Through the design of the deflector plate 8, the delivery smoothness of the filtrate water can be further improved.

[0032] Specifically, the delivery branch pipe 4 is vertically connected to the water receiving tank 2 and the circulation water tank 5, and the delivery branch pipe 4 is vertically connected to the electromagnetic flowmeter 6 through a vertical branch pipe 401. Through the design of the above vertical connection, it is ensured that the electromagnetic flowmeter 6 is always full-pipe measured, thus ensuring that there is no overflow of filtrate water in the overall measurement system.

[0033] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for quickly detecting the end of the feed into a filter press, characterized in that, It includes the following steps: S1. The feed pump of the filter press is connected to the PLC sub-station (7) in the filter press workshop for signal connection. The opening and closing of the feed pump of the filter press are operated. Meanwhile, the historical duration data during the period from the opening to the closing of the feed pump of the filter press is collected multiple times through the PLC. The abnormal data in the historical duration data is eliminated, and then the average value is taken. The average value is the historical feed end duration threshold of the filter press, and this duration threshold is used as the first condition for judging the end of the filter press feed. S2. A measurement system connected to the PLC sub-station (7) in the filter press workshop is installed on the filter press. The measurement system is used to measure the flow rate data of the filtrate water of the filter press. The flow rate data of the filtrate water of the filter press is collected through the PLC, and then the flow rate value of the filtrate water at the end of the historical feed of the filter press is determined through the flow rate data. The flow rate value is the flow rate threshold, and this flow rate threshold is used as the second condition for judging the end of the filter press feed. S3. The data of the first condition for judging the end of the filter press feed and the second condition for judging the end of the filter press feed are used as the reference values for judging the end of the filter press feed and transmitted to the PLC. When the filter press meets both judgment conditions simultaneously, it indicates that the feed of the filter press has ended.

2. The method for quickly detecting the end of the feeding of a filter press according to claim 1, wherein In step S1, the opening and closing of the feed pump of the filter press are manually operated.

3. A method for quickly detecting the end of the feed of a filter press according to claim 1 or 2, characterized in that, The abnormal data includes the longest historical duration data and the shortest historical duration data.

4. A method for quickly detecting the end of the feed of a filter press according to claim 3, characterized in that, In step S2, the measurement system includes a filtrate water tank (1) of the filter press and a water receiving tank (2) arranged below the filtrate water tank (1) of the filter press. The filtrate water tank (1) of the filter press is connected with a drain branch pipe (3) for leading out the filtrate water. The drain branch pipe (3) is connected to the top of the water receiving tank (2). The bottom of the water receiving tank (2) is connected with a conveying branch pipe (4). The conveying branch pipe (4) is connected with a circulation water tank (5), and an electromagnetic flowmeter (6) for measuring the flow rate data of the filtrate water of the filter press is connected to the central position of the conveying branch pipe (4). The electromagnetic flowmeter (6) is connected to the PLC sub-station (7) in the filter press workshop for signal connection.

5. A method for quickly detecting the end of the feed of a filter press according to claim 4, characterized in that, A connection hole (101) is opened at the central position of the bottom of the filtrate water tank (1) of the filter press. The filtrate water tank (1) of the filter press is connected with the drain branch pipe (3) through the connection hole (101).

6. A method for quickly detecting the end of the feed of a filter press according to claim 5, characterized in that, A crosswise guide plate (8) is arranged inside the water receiving tank (2). The guide plate (8) is used for guiding the filtrate water introduced into the inside of the water receiving tank (2), so that the filtrate water can flow smoothly to the conveying branch pipe (4).

7. A method for quickly detecting the end of the feed of a filter press according to claim 6, characterized in that, The conveying branch pipe (4) is vertically connected with the water receiving tank (2) and the circulation water tank (5), and the conveying branch pipe (4) is vertically connected with the electromagnetic flowmeter (6) through a vertical branch pipe (401).

8. A method for quickly detecting the end of the feed of a filter press according to claim 7, characterized in that, The drain branch pipe (3), the conveying branch pipe (4) and the vertical branch pipe (401) are all made of DN50 stainless steel pipes.

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