Sludge filter-pressing dehydration method and double-diaphragm filter-pressing system

Abstract

The invention discloses a sludge filter-pressing dehydration method and a double-diaphragm filter-pressing system. The method comprises the following steps: forming mixed sludge; conveying the mixed sludge into a filter pressing chamber; hot water at a preset temperature in the hot water tank is conveyed into a filter pressing chamber of the double-diaphragm filter press through the circulating hot water supply structure, so that the hot water exchanges heat with mixed sludge in the filter pressing chamber, the squeezing structure is controlled to squeeze a diaphragm chamber of the double-diaphragm filter press, the diaphragm chamber squeezes the mixed sludge in the filter pressing chamber, and the mixed sludge in the filter pressing chamber is discharged; carrying out filter pressing on water in the mixed sludge to form a filter cake from the mixed sludge; mixed sludge in the feeding channel is purged through the reverse purging structure, the mixed sludge in the feeding channel is discharged, the reverse purging structure continues to purge the feeding channel, and compressed air is discharged from the space between the adjacent filter plates of the double-diaphragm filter press and takes out moisture in the filter pressing cavity. The method has the advantages that the water content of the mixed sludge is reduced, and the transportation and disposal cost is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of sludge dehydration, in particular to a sludge filter pressing dehydration method and a double-diaphragm filter pressing system. Background Art

[0002] High moisture content is one of the main factors that limit the efficiency of sludge treatment and disposal. A series of standards and specifications for sludge transportation, pyrolysis, incineration, and land use in urban sewage treatment plants have made specific technical requirements for moisture content. Dehydration is a common key technical link in various sludge treatment and disposal routes. However, sludge is a highly mixed organic-inorganic heterogeneous complex system, presenting a stable colloidal and flocculent state, and solid-liquid separation is extremely difficult. Dehydration conditioning is an important guarantee for improving sludge dehydration performance and effectively achieving solid-liquid separation.

[0003] In the sludge treatment industry, chemical agents are generally used to condition the sludge, breaking the cell walls of the microorganisms in the sludge and releasing the water inside the cells to become free water. After conditioning, the sludge enters the diaphragm filter press through the sludge pump. During the feeding process, a certain feed pressure is applied to squeeze out most of the water in the sludge. After the feeding is completed, the sludge in the filter press chamber is further squeezed by the squeezing pump to squeeze out the water in the sludge, and finally reduce the moisture content of the sludge. However, the moisture content of the filter cake squeezed out by this method is still relatively high, which increases the transportation and disposal costs. At the same time, after the diaphragm filter press has squeezed the sludge, the filter cloth of the diaphragm filter press is cleaned by separating the partitions piece by piece and spraying water to the filter cloth through a water spray head. The cleaning time is relatively long and the cleaning is not thorough. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a sludge filter pressing dehydration method and a double diaphragm filter pressing system in view of the deficiencies of the prior art.

[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions.

[0006] A sludge filter pressing and dehydration method, comprising:

[0007] Step S1, adding conditioning agents to the sludge conditioning tank for stirring and mixing to form mixed sludge;

[0008] Step S2, conveying the mixed sludge to the filter press chamber of the double diaphragm filter press through the sludge conveying structure;

[0009] Step S3, transporting the hot water of a predetermined temperature in the hot water tank to the filter press chamber of the double-diaphragm filter press through a circulating hot water supply structure, so that the hot water and the mixed sludge in the filter press chamber are heat exchanged, and the hot water after the heat exchange flows back to the hot water tank;

[0010] Step S4, after a preset mixing time, controlling the pressing structure to press the mixed sludge in the filter press chamber and separate the filter cake and the filtrate;

[0011] Step S5, purge the mixed sludge in the feed channel through the back-purge structure, discharge the mixed sludge in the feed channel, close the feed channel, and the back-purge structure continues to purge the feed channel, so that the pressure in the filter press chamber increases to a predetermined value, and the compressed air is discharged from between adjacent filter plates of the double diaphragm filter press and takes out the moisture in the filter press chamber. After a preset period of time, the pressure in the filter press chamber is unloaded.

[0012] A preferred embodiment is that the sludge filter pressing and dehydration method further comprises:

[0013] Step S6, evacuating the filter press chamber by a vacuum pump to extract the moisture in the filter cake, so that the filter cake is biscuited to form a mud cake.

[0014] A preferred embodiment is that the sludge filter pressing and dehydration method further comprises:

[0015] Step S7, open the double diaphragm filter press and unload the mud cake.

[0016] A preferred embodiment is that the sludge filter pressing and dehydration method further comprises:

[0017] Step S8, adding cleaning agent into the hot water tank, circulating hot water to the filter press chamber of the double diaphragm filter press through the circulating hot water supply structure, the filter press chamber maintains a preset pressure, and the hot water soaks and rinses the filter press chamber and filter cloth in the double diaphragm filter press.

[0018] A preferred solution is that in step S5, the feed channel is opened, and the mixed sludge in the feed channel of the double diaphragm filter press is purged with compressed air in the air storage tank, so that the mixed sludge in the feed channel is discharged; the feed channel is closed, and the compressed air in the air storage tank continues to purge through the feed channel, and the compressed air enters the filter press chamber and increases the pressure in the filter press chamber. After the pressure increases to a predetermined value, the compressed air is discharged from between adjacent filter plates of the double diaphragm filter press and takes out the moisture in the filter press chamber. After a preset period of time, the pressure in the filter press chamber is unloaded.

[0019] A double diaphragm filter press system, comprising:

[0020] A sludge conditioning module is used to add conditioning agents into the sludge conditioning tank for stirring and mixing to form mixed sludge;

[0021] A sludge conveying structure, which is used to convey the mixed sludge to the filter press chamber of the double diaphragm filter press;

[0022] A circulating hot water supply structure, which is used to circulate the hot water in the hot water tank to the double diaphragm filter press to mix with the mixed sludge;

[0023] A plate-frame pressing unit, which is used to control the plate-frame filter pressing unit to perform a pressing operation after a preset mixing time, so as to separate the filter cake and the filtrate;

[0024] The back-purge structure is used to purge the mixed sludge in the feed channel to discharge the mixed sludge in the feed channel, and to increase the air pressure in the filter press chamber to discharge the moisture in the filter press chamber.

[0025] A preferred solution is that the double diaphragm filter press also includes a vacuum pump and a negative pressure tank, one end of the negative pressure tank is connected to the plate and frame filter press unit, and the other end is connected to the vacuum pump, and the vacuum pump is used to evacuate the filter press chamber to extract moisture from the filter press chamber.

[0026] The sludge filter press dehydration method and double-diaphragm filter press system provided by the embodiments of the present invention have at least the following beneficial effects: 1. The mixed sludge in the filter press chamber is mixed with hot water and heat exchange is performed quickly, so that the temperature of the mixed sludge in the filter press chamber is increased in the shortest time. The increase in the temperature of the mixed sludge is conducive to the dissolution of intracellular substances in the mixed sludge, further improving the cell wall breaking ability in the mixed sludge, and greatly improving the dehydration performance of the mixed sludge;

[0027] 2. In the process of heat exchange between mixed sludge and hot water, heat recycling is realized. The hot water after heat exchange re-enters the hot water tank for heating, and finally the temperature of the mixed sludge in the filter press chamber is basically consistent with the temperature of the hot water tank, which reduces energy consumption and operating costs during the hot water conditioning process;

[0028] 3. During the pressing process, the hot water can be circulated to achieve mutual exchange of heat, further increase the temperature of the mixed sludge in the filter press chamber, and make the mixed sludge pressed at a high temperature, which can further reduce the moisture content of the mixed sludge;

[0029] 4. After the pressing, the mud-water mixture in the feed pipeline of the double-diaphragm filter press is purged by compressed air to be discharged to the sewage pipe network. At the same time, the residual water between the diaphragm filter plates is discharged by compressed air after the purging stage; and preparations are made for the next step of vacuum drying;

[0030] 5. After the purging is completed, the filter press chamber is vacuumed during the pressing process. While ensuring that the temperature of the mixed sludge in the filter press chamber is high, the evaporation temperature of the mixed sludge is reduced through a high vacuum environment to further remove the moisture in the mixed sludge, thereby reducing the moisture content of the mixed sludge and reducing the transportation and disposal costs;

[0031] 6. At the same time, the filter cloth can be immersed and rinsed at high temperature. Compared with traditional filter cloth cleaning, it will not waste water, save costs, greatly reduce the filter cloth attenuation rate and extend the life of the filter cloth, thereby reducing production and operation costs.

[0032] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the following specifically cites a preferred embodiment and describes it in detail with the accompanying drawings as follows. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a flow chart of the present invention;

[0034] Figure 2 The process system of the present invention is schematically shown in FIG. Figure 1 ;

[0035] Figure 3 The process system of the present invention is schematically shown in FIG. Figure 2 . DETAILED DESCRIPTION

[0036] In order to explain the idea and purpose of the present application, the present application will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0037] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by technicians in the technical field of this application; the terms used in the specification of the application herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. The terms "first", "second", "left", "right", etc. in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, not to describe a specific order.

[0038] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0039] The first embodiment, as Figure 1 and Figure 3 As shown, the embodiment of the present application provides a sludge filter pressing and dehydration method, comprising:

[0040] Step S1, adding conditioning agents to the sludge conditioning tank for stirring and mixing to form mixed sludge;

[0041] Conditioning agents are added to the sludge conditioning tank and stirred to form mixed sludge. The sludge pipeline 1 transports the conditioned mixed sludge into the homogenization tank 2 for temporary storage.

[0042] Step S2, conveying the mixed sludge to the filter press chamber of the double diaphragm filter press 12 through the sludge conveying structure;

[0043] The conditioned sludge in the homogenization tank 2 is transported into the double diaphragm filter press 12 through the filter press mud pump 6.

[0044] Step S3, the hot water of a predetermined temperature in the hot water tank 33 is transported to the filter press chamber of the double-diaphragm filter press 12 through a circulating hot water supply structure, so that the hot water is heat-exchanged with the mixed sludge in the filter press chamber, and the hot water after the heat exchange flows back to the hot water tank 33;

[0045] The temperature of the hot water in the hot water tank 33 is 45 to 100 degrees, the heat exchange time is 1200 seconds to 2000 seconds, and the temperature difference between the return hot water and the hot water entering the filter press chamber is less than 5 degrees, that is, the return hot water temperature is 40 to 95 degrees. The purpose of this is to make the temperature of the mixed sludge as high as possible and close to the hot water temperature, thereby reducing energy consumption and lowering operating costs.

[0046] Step S4, after a preset mixing time, the pressing structure is controlled to press the diaphragm chamber of the double diaphragm filter press, the diaphragm chamber squeezes the mixed sludge in the filter press chamber, the water in the mixed sludge is filtered out, and the water is discharged from the filtrate outlet, so that the mixed sludge forms a filter cake;

[0047] The mixed sludge and hot water are mixed for 15 to 60 minutes, so that the mixed sludge is in a high temperature state, which is helpful for dehydration of the mixed sludge.

[0048] In this step, the hot water in the hot water tank 33 is continuously provided to the diaphragm chamber of the double diaphragm filter press by the squeezing pump, and the hot water in the diaphragm chamber flows back to the hot water tank 33. When the squeezing pump pumps the hot water in the hot water tank 33 into the diaphragm chamber, the diaphragm chamber is in an expanded state, and the expanded diaphragm chamber squeezes the mixed sludge in the filter press chamber to filter out the water in the mixed sludge.

[0049] The temperature of the hot water in the diaphragm chamber is transferred to the filter press chamber, further increasing the temperature of the filter press chamber and facilitating the dehydration of the filter cake.

[0050] Step S5, open the feed channel, purge the mixed sludge in the feed channel through the back-purge structure, discharge the mixed sludge in the feed channel, close the sludge feed port and filtrate discharge port of the feed channel, and the back-purge structure continues to purge the feed channel so that the pressure in the filter press chamber increases to a predetermined value, and the compressed air is discharged from between adjacent filter plates of the double diaphragm filter press 12 and takes out the moisture in the filter press chamber. After a preset period of time, the pressure in the filter press chamber is unloaded.

[0051] The pressure in the filter press chamber increases to 0.1 MPa to 0.5 MPa, and the compressed air is discharged from between adjacent filter plates of the double diaphragm filter press 12 for 300 seconds to 900 seconds.

[0052] In step S5, the squeezing pump continues to supply hot water to the diaphragm chamber, the diaphragm chamber is always in an expanded state, the filter press chamber is always in a squeeze state, and the hot water in the diaphragm chamber also transfers heat to the filter press chamber and the filter cake, making the filter cake dehydration effect better.

[0053] The second embodiment, as Figure 1 and Figure 3 As shown, the difference between this embodiment and the first embodiment is that the sludge filter pressing and dehydration method further includes:

[0054] Step S6, evacuating the filter press chamber by a vacuum pump so that the vacuum degree in the filter press chamber reaches a predetermined value, so that the water in the filter cake is evaporated and extracted, and the filter cake is formed into a dry mud cake.

[0055] The vacuum degree in the filter press chamber is -0.1 to -0.09 MPa.

[0056] In step S6, the squeezing pump continues to supply hot water to the diaphragm chamber, the diaphragm chamber is always in an expanded state, the filter press chamber is always in a squeezed state, and the hot water in the diaphragm chamber also transfers heat to the filter press chamber. The higher the temperature in the filter press chamber, the faster the water evaporates. Figure 1 and Figure 3 As shown, the difference between this embodiment and the second embodiment is that the sludge filter pressing and dehydration method further includes:

[0057] Step S7, opening the filter plate of the double-diaphragm filter press 12 to discharge the mud cake.

[0058] Before step S7, the squeezing is stopped, that is, the squeezing pump stops providing hot water to the diaphragm chamber, and the hot water in the diaphragm chamber flows back to the hot water tank, and the hot water is recycled.

[0059] The fourth embodiment, as Figure 1 and Figure 3 As shown, the difference between this embodiment and the third embodiment is that the sludge filter pressing and dehydration method further includes:

[0060] Step S8, adding cleaning agent into the hot water tank 33, circulating hot water to the filter press chamber of the double diaphragm filter press 12 through the circulating hot water supply structure, the filter press chamber maintains a preset pressure, and the hot water soaks and rinses the filter cloth and filter plate in the double diaphragm filter press 12.

[0061] It saves water, recycles hot water, and has better cleaning effects on filter cloth and filter plate.

[0062] The fifth embodiment, as Figure 1 and Figure 3 As shown, the difference between this embodiment and the first embodiment is: in the step S5, the sludge feed port of the feed channel is opened, and the mixed sludge in the feed channel of the double diaphragm filter press 12 is purged by the compressed air in the air storage tank 20, so that the mixed sludge in the feed channel is discharged; the sludge feed port of the feed channel is closed, and the compressed air in the air storage tank 20 continues to purge through the feed channel, and the compressed air enters the filter press chamber and increases the pressure in the filter press chamber. After the pressure increases to a predetermined value, the compressed air is discharged from between adjacent filter plates of the double diaphragm filter press 12 and takes out the moisture in the filter press chamber. After a preset period of time, the pressure in the filter press chamber is unloaded.

[0063] The sixth embodiment, as Figure 1 and Figure 3 As shown, a double-diaphragm filter press system includes: a sludge conditioning module, a sludge conveying structure, a circulating hot water supply structure, a plate and frame pressing unit and a back-purge structure.

[0064] A sludge conditioning module is used to add conditioning agents into the sludge conditioning tank for stirring and mixing to form mixed sludge;

[0065] A sludge conveying structure, which is used to convey the mixed sludge to the filter press chamber of the double diaphragm filter press 12;

[0066] A circulating hot water supply structure, which is used to transport the hot water in the hot water tank 33 to the double diaphragm filter press 12 to mix with the mixed sludge;

[0067] A plate-and-frame pressing unit, which is used to perform a pressing operation after a preset mixing time to separate filter cake and filtrate;

[0068] The back-purge structure is used to purge the mixed sludge in the feed channel to discharge the mixed sludge in the feed channel, and to increase the pressure in the filter press chamber to discharge the moisture in the filter press chamber.

[0069] The sludge conditioning module is used to add conditioning agents to the sludge conditioning tank for stirring and mixing to form mixed sludge. The conditioning agents are added to the sludge conditioning tank and stirred to form mixed sludge. The sludge pipeline 1 transports the conditioned mixed sludge into the homogenization tank 2 for temporary storage.

[0070] The sludge conveying structure comprises a sludge inlet pump 6, a sludge inlet pneumatic valve 4 of the sludge inlet pump 6, a sludge inlet pneumatic valve 7 of the filter press, and a pneumatic valve 23 for filtrate discharge.

[0071] like Figure 1 and Figure 3 As shown, the double diaphragm filter press 12 includes a feed channel and a plurality of filter plates, the feed channel is connected to the plurality of filter plates respectively, a filter press chamber is formed between adjacent filter plates, a diaphragm chamber is provided in the filter plate, and the feed channel is not connected to the diaphragm chamber. The diaphragm chamber is isolated from the filter press chamber and the feed channel respectively.

[0072] like Figure 1 and Figure 3 As shown, the mud inlet pneumatic valve 4 of the mud inlet pump 6, the mud inlet pneumatic valve 7 of the filter press, and the pneumatic valve 23 for filtrate discharge are opened, and the mixed sludge after conditioning in the homogenization tank 2 is transported into the double diaphragm filter press 12 through the mud inlet pump 6. After the mixed sludge in the filter press chamber of the double diaphragm filter press 12 is filled with the mixed sludge, the feeding is completed, and the mud inlet pneumatic valve 4 of the mud inlet pump 6, the mud inlet pneumatic valve 7 of the filter press, and the pneumatic valve 23 for filtrate discharge are closed.

[0073] like Figure 1 and Figure 3 As shown, the circulating hot water supply structure includes a hot water tank 33, a water inlet pneumatic valve 3 of a mud pump 6, a hot water circulation pneumatic valve 27 and a hot water return pipe 29. The water inlet pneumatic valve 3 of the mud pump 6, the mud inlet pneumatic valve 7 of the filter press and the hot water circulation pneumatic valve 27 are opened, and the hot water in the hot water tank 33 is transported into the filter press chamber of the double diaphragm filter press 12 through the mud pump 6 and fully heat exchanged with the mixed sludge. The water after heat exchange re-enters the hot water tank 33 through the hot water return pipe 29 for recycling; after complete heat exchange, the water inlet pneumatic valve 3 of the mud pump 6, the mud inlet pneumatic valve 7 of the filter press and the hot water circulation pneumatic valve 27 are closed.

[0074] like Figure 1 and Figure 3 As shown, the plate and frame pressing unit includes a pressing pump 30, a pressing water inlet pneumatic valve 25, a filtrate discharge pneumatic valve 23 and a hot water circulation regulating pneumatic valve 26, which are used to control the plate and frame pressing unit to perform a pressing operation after a preset mixing time to separate the filter cake and the filtrate.

[0075] like Figure 1 and Figure 3As shown, the pressing water inlet pneumatic valve 25 and the filtrate discharge pneumatic valve 23 are opened, and the hot water circulation regulating pneumatic valve 26 is opened, and the hot water in the hot water tank 33 is transported into the diaphragm chamber of the double diaphragm filter press 12 through the pressing pump 30. The diaphragm chamber is in an expanded state, and the diaphragm chamber squeezes the mixed sludge in the filter press chamber, and the water in the mixed sludge is squeezed out and discharged to the sewage treatment system through the filtrate discharge pipeline 10. At the same time, during the pressing process, the heat in the diaphragm chamber of the double diaphragm filter press 12 is further transferred to the filter press chamber, thereby increasing the temperature of the mixed sludge in the filter press chamber, which is beneficial to squeezing out the water in the mixed sludge.

[0076] like Figure 1 and Figure 3 As shown, the back-purge structure includes a compressed air pipeline 16, a three-way pneumatic valve 14, a compressed air pipeline 16, an air storage tank 20 and a back-purge pipeline 13. The air storage tank 20 is connected to an air compressor 19 and an instrument 21.

[0077] like Figure 1 and Figure 3 As shown, after squeezing, the three-way pneumatic valve 14 is opened, the compressed air pipeline 16 and the sludge return pneumatic valve 9 are opened, and the filtrate discharge pneumatic valve 23 is closed. The air storage tank 20 allows the compressed air to enter the feed channel of the filter press through the back-blowing pipeline 13, and the mixed sludge in the feed channel is discharged to the sewage treatment system through the back-blowing return pipeline 24. After a period of blowing, the mixed sludge in the feed channel is discharged, the sludge return pneumatic valve 9 is closed, and a second blow is performed. The compressed air in the air storage tank 20 continues to enter the feed channel. Entering the filter press chamber, since the sludge return pneumatic valve 9 and the filtrate discharge pneumatic valve 23 are both in the closed state, the filter press chamber is in a closed environment, and the pressure in the filter press chamber continues to rise with the entry of compressed air. When the pressure rises to a certain value, the compressed air will be discharged through the filter plates and at the same time, the moisture in the filter press chamber will be taken out synchronously, further reducing the moisture content of the filter cake; when this process lasts for a certain period of time, the three-way pneumatic valve 14 is closed and the filtrate discharge pneumatic valve 23 is opened to unload the pressure in the filter press chamber.

[0078] like Figure 1 and Figure 3As shown, in the vacuum drying stage: open the three-way pneumatic valve 14 and switch to the vacuum pipeline 15, close the filtrate discharge pneumatic valve 23, and realize the vacuum negative pressure state in the filter press chamber through the vacuum pump 18. When the negative pressure reaches a certain value, the water in the filter cake is in a high vacuum state, so that the evaporation temperature of the water decreases, and the water in the filter cake in the filter press chamber is extracted in the form of steam, further reducing the water content in the filter cake; enter the negative pressure tank 17 through the vacuum pipeline 15 and condense into liquid water; after a period of continuous vacuum, and the squeezed hot water continuously exchanges heat with the filter cake in the filter press chamber, the filter cake in the filter press chamber is always kept at a high temperature. After the vacuum drying is completed, close the three-way pneumatic valve 14, at the same time, turn off the squeeze pump 30 and open the squeezed water reflux pneumatic valve 28 and the hot water circulation regulating pneumatic valve 26, so that the squeezed water in the filter press diaphragm chamber enters the hot water tank 33 through the squeezed water reflux pipeline 31. After the vacuum drying is completed, the mud unloading operation can be started.

[0079] like Figure 1 and Figure 3 As shown, in the mud unloading stage: the double diaphragm filter press 12 is controlled by the PLC control module 5 to perform opening, plate pulling, and mud unloading operations according to the program until the mud unloading is completed.

[0080] like Figure 1 and Figure 3 As shown, filter cloth cleaning stage: add filter cloth cleaning agent into the hot water tank 33, open the water inlet pneumatic valve 3 of the mud pump 6, the mud inlet pneumatic valve 7 of the filter press and the hot water circulation pneumatic valve 27, and input the cleaning hot water into the filter press chamber of the double diaphragm filter press 12 by starting the mud pump 6. At the same time, the cleaning hot water enters the hot water tank 33 through the hot water return pipe 29, and keeps the filter press chamber at a certain pressure to ensure that the filter press chamber is always filled with cleaning hot water, so as to realize the function of hot water immersion of the filter cloth, dissolve the residual blockage of the agent on the filter cloth by the cleaning hot water, and at the same time, the cleaning hot water is continuously circulated to flush the filter cloth. After the continuous circulation lasts for a certain period of time, the filter cloth can be cleaned. After the filter cloth is cleaned, close the mud pump 6 of the filter press and the water inlet pneumatic valve 3 of the mud pump 6 and the mud inlet pneumatic valve 7 of the filter press and the hot water circulation pneumatic valve 27; the filter cloth cleaning is completed.

[0081] like Figure 1 and Figure 3 As shown, the double diaphragm filter press 12 also includes a vacuum pump 18 and a negative pressure tank 17. One end of the negative pressure tank 17 is connected to the plate and frame filter press unit, and the other end is connected to the vacuum pump 18. The vacuum pump 18 is used to evacuate the filter press chamber to extract moisture from the filter press chamber.

[0082] like Figure 1 and Figure 3As shown, one end of the homogenizing tank 2 is connected to the feed channel of the double diaphragm filter press 12 through the mud feed pump 6, a mud feed pneumatic valve 4 of the mud feed pump 6 is provided between the homogenizing tank 2 and the mud feed pump 6, and the mud feed pump 6 is connected to the double diaphragm filter press 12 through the filter press mud feed pneumatic valve 7.

[0083] like Figure 1 and Figure 3 As shown, the hot water tank 33 is connected to the feed channel of the double-diaphragm filter press 12 through the mud feed pump 6, and a water inlet pneumatic valve 3 of the mud feed pump 6 is provided between the hot water tank 33 and the mud feed pump 6.

[0084] like Figure 1 and Figure 3 As shown, the mud feed pump 6 is connected to the feed channel of the double diaphragm filter press 12 through the filter press mud feed pipeline 8 .

[0085] like Figure 1 and Figure 3 As shown, the filter press chamber of the double-diaphragm filter press 12 is connected to the hot water tank 33 via a hot water return pipeline 29 , and a hot water circulation regulating pneumatic valve 26 is connected between the hot water return pipeline 29 and the hot water tank 33 .

[0086] like Figure 1 and Figure 3 As shown, the hot water tank 33 is connected to a heat pump heating module 34 and a tap water inlet pipeline 35, and the hot water tank 33 is connected to the filter press mud inlet pneumatic valve 7 through the screw pump inlet 32. The hot water tank 33 supplies hot water to the double diaphragm filter press 12 through the pressing pipeline 22 for flushing.

[0087] like Figure 1 and Figure 3 As shown, the hot water tank 33 is connected to the filter press chamber of the double diaphragm filter press 12 through the squeeze pump 30, and a squeeze water inlet pneumatic valve 25 is provided between the squeeze pump 30 and the filter press chamber of the double diaphragm filter press 12. The filter press chamber of the double diaphragm filter press 12 is connected to the hot water tank 33 through the squeeze water circulation return pipeline 11, and the squeeze water circulation return pipeline 11 is provided with a squeeze water circulation pneumatic valve 26.

[0088] like Figure 1 and Figure 3 As shown, one end of the gas storage tank 20 is connected to the feed channel of the double diaphragm filter press 12 through a three-way pneumatic valve 14, one end of the negative pressure tank 17 is connected to the plate and frame filter press unit through the three-way pneumatic valve 14, and the other end is connected to the vacuum pump 18.

[0089] The above is a specific implementation of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A sludge filter press dehydration method, characterized in that: include: Step S1, adding conditioning agents to the sludge conditioning tank for stirring and mixing to form mixed sludge; Step S2, conveying the mixed sludge to the filter press chamber of the double diaphragm filter press through the sludge conveying structure; Step S3, transporting the hot water of a predetermined temperature in the hot water tank to the filter press chamber of the double-diaphragm filter press through a circulating hot water supply structure, so that the hot water and the mixed sludge in the filter press chamber are heat exchanged, and the hot water after the heat exchange flows back to the hot water tank; Step S4, after a preset mixing time, the pressing structure is controlled to press the diaphragm chamber of the double diaphragm filter press, the diaphragm chamber squeezes the mixed sludge in the filter press chamber, the water in the mixed sludge is filtered out, and the water is discharged from the filtrate outlet, so that the mixed sludge forms a filter cake; Step S5, purge the mixed sludge in the feed channel through the back-purge structure, discharge the mixed sludge in the feed channel, close the sludge feed port and the filtrate discharge port of the feed channel, and the back-purge structure continues to purge the feed channel so that the pressure in the filter press chamber increases to a predetermined value, and the compressed air is discharged from between adjacent filter plates of the double diaphragm filter press and takes out the moisture in the filter press chamber. After a preset period of time, the pressure in the filter press chamber is unloaded.

2. The sludge filter pressing and dehydration method according to claim 1, characterized in that: The sludge filter pressing and dehydration method also includes: Step S6, evacuating the filter press chamber by a vacuum pump so that the vacuum degree in the filter press chamber reaches a predetermined value, so that the water in the filter cake is evaporated and extracted, and the filter cake is formed into a dry mud cake.

3. The sludge filter pressing and dehydration method according to claim 2, characterized in that: The sludge filter pressing and dehydration method also includes: Step S7, open the double diaphragm filter press and unload the mud cake.

4. The sludge filter pressing and dehydration method according to claim 3, characterized in that: The sludge filter pressing and dehydration method also includes: Step S8, adding cleaning agent into the hot water tank, circulating hot water to the filter press chamber of the double diaphragm filter press through the circulating hot water supply structure, the filter press chamber maintains a preset pressure, and the hot water soaks and rinses the filter cloth and filter plate in the double diaphragm filter press.

5. The sludge filter pressing and dehydration method according to claim 1, characterized in that: In the step S5, the sludge feed port of the feed channel is opened, and the mixed sludge in the feed channel of the double diaphragm filter press is purged by the compressed air in the air storage tank, so that the mixed sludge in the feed channel is discharged; the sludge feed port of the feed channel is closed, and the compressed air in the air storage tank continues to purge through the feed channel, and the compressed air enters the filter press chamber and increases the pressure in the filter press chamber. After the pressure increases to a predetermined value, the compressed air is discharged from between adjacent filter plates of the double diaphragm filter press and takes out the moisture in the filter press chamber. After a preset period of time, the pressure in the filter press chamber is unloaded.

6. A double diaphragm filter press system, characterized in that: include: A sludge conditioning module is used to add conditioning agents into the sludge conditioning tank for stirring and mixing to form mixed sludge; A sludge conveying structure, which is used to convey the mixed sludge to the filter press chamber of the double diaphragm filter press; A circulating hot water supply structure, which is used to circulate the hot water in the hot water tank to the double diaphragm filter press to mix with the mixed sludge; A plate-frame pressing module, which is used to control the plate-frame pressing unit to perform a pressing operation after a preset mixing time, so as to separate the filter cake and the filtrate; The back-purge structure is used to purge the mixed sludge in the feed channel to discharge the mixed sludge in the feed channel, and to increase the pressure in the filter press chamber to discharge the moisture in the filter press chamber.

7. The double diaphragm filter press system according to claim 6, characterized in that: The double diaphragm filter press system also includes a vacuum pump and a negative pressure tank. One end of the negative pressure tank is connected to the plate and frame filter press unit, and the other end is connected to the vacuum pump. The vacuum pump is used to evacuate the filter press chamber to extract moisture from the filter press chamber.

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