Oxidation pneumatic filter press cabin bottom slurry treatment and recycling method and device

Abstract

The invention relates to the technical field of industrial waste treatment, and discloses an oxidation pneumatic filter press cabin bottom slurry treatment and recycling method and device, the device comprises a slurry treatment system, the slurry treatment system comprises a third crystallizer, a pneumatic filter press, a plate-and-frame filter press, a third washing liquid receiving tank, a pulping tank and a buffer tank, the pneumatic filter press, the plate-and-frame filter press and the third washing liquid receiving tank are arranged on the upper layer, and a feed port of the third crystallizer is communicated with a discharge port of the pulping tank through a pipeline. Solid-liquid separation of slurry is achieved through the plate-and-frame filter press, filtrate is circularly used for the pneumatic filter press, the requirement for fresh water is remarkably reduced, the resource utilization rate is increased, acetic acid is accurately injected, extra consumption is reduced, cost is reduced, sewage discharge is reduced through recycling of washing liquid and lubricating water, the treatment difficulty and cost are reduced, and the environment-friendly requirement is met; and green production and sustainable development are promoted.

Description

Technical Field

[0001] The invention relates to the technical field of industrial waste treatment, and in particular to a method and device for treating and recycling slurry from the bottom of a bilge of an oxidative pneumatic filter press. Background Art

[0002] In the industrial production process, pneumatic filter presses are widely used in the solid-liquid separation process. The bearings in the filter press need to be lubricated by water to reduce friction, reduce wear and extend the service life of the equipment. However, since the filter press is under a large load during operation, there are often sealing problems inside the equipment, causing the lubricating water to mix with the slurry during use, forming slurry flowing to the bottom of the filter press. The slurry at the bottom of the bilge then enters the subsequent oxidation system, thereby affecting the reaction process of the entire system.

[0003] The existing pneumatic filter press system consists of a feed port, filter plates, bearings, a lubricating water system, and a bilge sewage discharge device. The lubricating water is introduced into the bearing part through a specific pipeline to reduce the wear of the bearing. However, due to deficiencies in the equipment design, the lubricating water will mix with the leaked slurry during use, forming slurry that is retained in the bilge. After entering the oxidation reactor, these slurries will bring in a large amount of water. The introduction of water will inhibit the oxidation reaction, resulting in reduced reaction efficiency and increased by-product content. In order to ensure the normal progress of the oxidation reaction, the amount of water produced in the system must be increased, which directly increases the water treatment load of the oxidation reactor, not only leading to an increase in acetic acid consumption, but also increasing the amount of sewage discharged, thereby increasing the difficulty of sewage treatment, causing adverse effects on the environment and cost. Summary of the invention

[0004] In view of the shortcomings of the prior art, the present invention provides a method and device for treating and recycling the bilge slurry of an oxidizing pneumatic filter press, which solves the problem in the prior art that the introduction of water into the oxidation reactor leads to reaction inhibition, increased by-products, increased water treatment load and sewage discharge.

[0005] To achieve the above objectives, the present invention is implemented through the following technical scheme: an oxidizing pneumatic filter press bilge slurry treatment and recycling device, including a slurry treatment system, the slurry treatment system is composed of a third crystallizer, a pneumatic filter press, a plate and frame filter press, a third washing liquid receiving tank, a pulping tank and a buffer tank, the pneumatic filter press, the plate and frame filter press and the third washing liquid receiving tank are arranged on the upper layer, the feed port of the third crystallizer is connected with the discharge port of the pulping tank through a pipeline, the discharge port of the third crystallizer is connected with the washing port of the pneumatic filter press through a pipeline, the feed port of the pulping tank is connected with the discharge port of the plate and frame filter press through a pipeline, the feed port of the third washing liquid receiving tank is connected with the liquid outlet of the plate and frame filter press through a pipeline, the discharge port of the third washing liquid receiving tank is connected with the washing port of the pneumatic filter press through a pipeline, and the feed port and discharge port of the buffer tank are respectively connected with the discharge port of the pneumatic filter press and the feed port of the plate and frame filter press through a pipeline.

[0006] Preferably, a first pump body is provided between the buffer tank and the plate and frame filter press, a second pump body is provided between the plate and frame filter press and the pulping tank, and a third pump body is provided between the third crystallizer and the pneumatic filter press. Each pump body is used to transport the slurry to each process in sequence to ensure the flow and pressure stability of the slurry in the system.

[0007] Preferably, an acetic acid filling pipe is fixedly connected to the side wall of the beating tank, so that the beating effect of the filter cake is improved by adding acetic acid.

[0008] Preferably, both the buffer tank and the pulping tank are provided with a stirrer to prevent sedimentation of the slurry and maintain uniform distribution of the slurry.

[0009] Preferably, a pressure control system is provided in the buffer tank to ensure the stability of the pressure of the pneumatic filter press system.

[0010] A method for treating and recycling slurry from the bottom of an oxidizing pneumatic filter press comprises the following steps:

[0011] S1: Introduce the slurry formed on the bottom of the bilge into the buffer tank;

[0012] S2: The buffer tank is equipped with an agitator to prevent material sedimentation and a pressure control system to ensure the stability of the system pressure;

[0013] S3: The slurry in the buffer tank is transported to the plate and frame filter press by a pump. The pump inlet adopts bottom feeding and is equipped with a reflux to the buffer tank to prevent the sedimentation of the material.

[0014] S4: Enter the plate and frame filter press for solid-liquid separation. Two plate and frame filter presses are used in parallel to ensure the continuous operation of the system;

[0015] S5: The filter cake enters a pulping tank for pulping. After pulping with acetic acid, it is pumped to the third crystallizer for recycling;

[0016] S6: The filtrate enters the third washing liquid receiving tank and is used for washing the filter cake by the pneumatic filter press to reduce the use of fresh water.

[0017] Preferably, the buffer tank in step S2 is used to maintain the uniformity of the slurry through an agitator to prevent the slurry from settling due to long-term stillness.

[0018] Preferably, in step S4, two plate and frame filter presses are switched in parallel to ensure continuous operation of the plate and frame filter presses and reduce system downtime.

[0019] Preferably, acetic acid is added in step S5 for pulping to improve the fluidity of the filter cake and the smoothness of pump transportation.

[0020] Preferably, in step S6, the filter cake of the pneumatic filter press is washed by using the filtrate in the third washing liquid receiving tank to reduce the consumption of fresh water and realize the recycling of water resources.

[0021] The present invention provides a method and device for treating and recycling slurry from the bottom of an oxidizing pneumatic filter press. It has the following beneficial effects:

[0022] 1. The present invention realizes efficient recycling of slurry and reduces slurry loss by adopting a slurry and water separation process. The slurry in the system is separated into solid and liquid by a plate and frame filter press, and the filtrate enters the third washing liquid receiving tank and is used in the pneumatic filter press for washing the filter cake. This design not only recovers the solid matter in the slurry, but also greatly reduces the demand for fresh water replenishment in the system, significantly saves water resources, ensures the cleaning effect of the pneumatic filter press, extends the working life of the system, and improves the operating efficiency of the equipment.

[0023] 2. The present invention further reduces the system's dependence on fresh water by repeatedly using the filtrate as lubricating water during the washing process. The washing liquid is provided by the third washing liquid receiving tank during the circulation process, avoiding a large amount of water resource waste caused by multiple cleanings in traditional equipment and reducing water consumption. The recycling of this lubricating water not only meets the lubrication requirements of the pneumatic filter press, but also greatly reduces the fresh water consumption in the production process, significantly improving the utilization efficiency of water resources, while reducing the company's water treatment costs and achieving green production and sustainable development.

[0024] 3. The present invention reduces the system's demand for acetic acid by separating excess water and not introducing it directly into the reaction system. The acetic acid used in the pulping process is accurately injected through a filling pipe, reducing the extra consumption of acetic acid caused by the introduction of water. This process design not only improves the utilization rate of acetic acid, but also reduces the amount of acetic acid used in the production process, thereby effectively controlling the production cost. By reducing the use of acetic acid, not only the cost of chemical procurement is saved, but also the production operation is made safer and more environmentally friendly, meeting the optimization needs of cost-effectiveness.

[0025] 4. The present invention significantly reduces the amount of wastewater generated and reduces sewage discharge by recycling the washing liquid and lubricating water inside the system. Compared with the traditional process, the device effectively reduces the total amount of sewage discharged, reduces the difficulty and cost of subsequent sewage treatment, and the small amount of sewage generated is less difficult to treat due to the reduced consumption of chemicals in the system, further reducing the cost of sewage treatment. In addition, by reducing the generation of sewage, the present invention meets the strict requirements of environmental emissions to a certain extent, reduces the burden on the environment during the production process, and provides strong support for enterprises to achieve green production, reduce emissions, and meet emission standards. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A perspective view of the present invention;

[0027] Figure 2 It is a schematic structural diagram of the acetic acid filling pipe of the present invention;

[0028] Figure 3 It is a schematic diagram of the process of the present invention.

[0029] Among them, 1. the third crystallizer; 2. the pneumatic filter press; 3. the plate and frame filter press; 4. the third washing liquid receiving tank; 5. the rack; 6. the pulping tank; 7. the buffer tank; 8. the acetic acid filling pipe. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the specification of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] Example:

[0032] Please refer to the attached Figure 1 - Attachment Figure 3The embodiment of the present invention provides a device and method for treating and recycling slurry from the bottom of an oxidizing pneumatic filter press, which is designed to efficiently recycle and reuse slurry and water resources, reduce the use of fresh water and chemicals, and reduce sewage discharge, so as to achieve the goals of environmental protection and cost savings.

[0033] Device composition and configuration

[0034] The device mainly includes the following components:

[0035] The third crystallizer 1 is used to further extract usable substances from the slurry. The feed port of the third crystallizer is connected to the discharge port of the beating tank 6 through a pipeline to ensure that the slurry after beating can directly enter the crystallizer for crystallization treatment.

[0036] Pneumatic filter press 2: used for further washing of the filter cake and solid-liquid separation. The pneumatic filter press can efficiently wash the filter cake under high pressure conditions, and its feed port is connected to the third washing liquid receiving tank 4 to reuse the washing liquid and reduce the use of fresh water.

[0037] Plate and frame filter press 3: The plate and frame filter press is used for preliminary solid-liquid separation. Two plate and frame filter presses are set in parallel, and the continuous operation of the system is ensured by switching. When the system is performing solid-liquid separation, the first pump body transports the slurry from the buffer tank 7 to the plate and frame filter press, reducing the risk of system blockage.

[0038] The third washing liquid receiving tank 4 is used to collect and store washing liquid from the plate and frame filter press and the pneumatic filter press. The third washing liquid receiving tank is connected to the washing port of the pneumatic filter press through a pipeline to ensure the recycling of washing liquid and further reduce the consumption of fresh water.

[0039] Beating tank 6: used for beating the filter cake. An acetic acid filling pipe 8 is provided on the side wall of the beating tank, which can quantitatively inject acetic acid to improve the beating effect and ensure that the filter cake can be smoothly transported to the third crystallizer 1 for recycling.

[0040] Buffer tank 7: used for temporary storage and adjustment of slurry, to prevent sedimentation of slurry and to maintain stable pressure in the system. The buffer tank is equipped with an agitator to maintain the uniformity of the slurry, and is equipped with a pressure control system to ensure stable operation of the system. The outlet of the buffer tank is connected to the feed port of the plate and frame filter press through the first pump body, so as to transport the slurry to the separation link.

[0041] Procedure

[0042] The specific operation method of this device is as follows:

[0043] Introduce slurry into buffer tank S1

[0044] The slurry formed on the bottom of the bilge is introduced into the buffer tank 7 through a pipeline. The buffer tank is equipped with an agitator to prevent the slurry from settling when it is stationary. The buffer tank is also equipped with a pressure control system to ensure that the pressure in the system is stable to avoid blockage or pressure fluctuations during subsequent treatment.

[0045] Conveyor S2 from buffer tank to plate and frame filter press

[0046] The slurry in the buffer tank 7 is transported to the plate-frame filter press 3 through the first pump body for preliminary solid-liquid separation. To ensure the continuous transportation of the slurry, a bottom feed port is set at the pump inlet, and part of the slurry is returned to the buffer tank through a reflux pipe to prevent the slurry from settling at the pump inlet and affecting the system operation.

[0047] Solid-liquid separation of plate and frame filter press S3

[0048] The plate and frame filter press is used to separate the solid and liquid in the slurry, and the separated filter cake enters the pulping tank 6 for further processing. The device uses two parallel plate and frame filter presses, which is convenient for switching operations to ensure continuous operation of the system. The parallel processing of the plate and frame filter presses allows the system to operate normally when a single filter press is cleaned or maintained, avoiding production interruptions caused by downtime.

[0049] Slurry treatment of filter cake S4

[0050] The separated filter cake is transported to the pulping tank 6. An acetic acid filling pipe 8 is installed on the side wall of the pulping tank. The quantitative addition of acetic acid helps to improve the fluidity of the filter cake and improve the pulping effect. The agitator ensures that the acetic acid and the filter cake are fully mixed so as to break up the filter cake and form a slurry state suitable for transportation. The treated slurry is transported to the third crystallizer 1 through the second pump body and further recycled in the crystallizer.

[0051] Filtrate recovery and recycling S5

[0052] The separated filtrate enters the third washing liquid receiving tank 4, and then is used to wash the filter cake in the pneumatic filter press 2. By using the filtrate in the third washing liquid receiving tank to replace part of the fresh water, it not only saves water resources, but also ensures the washing effect of the pneumatic filter press, and reduces the operating cost of the system.

[0053] Wastewater discharge control and environmental protection measures S6

[0054] The device significantly reduces wastewater discharge by recycling washing liquid and lubricating water in each link. The reuse of washing liquid and lubricating water reduces the system's demand for fresh water, while also reducing wastewater discharge and pollutant discharge concentration. This design not only meets environmental protection requirements, reduces the difficulty and cost of sewage treatment, but also improves the system's resource utilization rate and achieves green production.

[0055] Working principle: The slurry is transported from the bottom of the bilge to the buffer tank 7 through a pipeline. At this time, the buffer tank serves as a temporary storage device for the slurry and has the function of stabilizing the system pressure. The buffer tank 7 is equipped with an agitator to prevent the slurry from settling due to long-term static state and ensure uniform distribution of the liquid. At the same time, the buffer tank is also equipped with a pressure control system to ensure that the entire system operates under stable pressure conditions and avoid failures in subsequent processes due to pressure fluctuations. The outlet of the buffer tank 7 is connected to the feed port of the plate-frame filter press 3 through the first pump body to ensure that the slurry can be stably transported to the separation link; the slurry coming out of the buffer tank 7 is transported to the plate-frame filter press 3 through the first pump body for preliminary solid-liquid separation. The device is designed with two parallel plate-frame filter presses to achieve switching use and ensure continuous operation of the system. The plate-frame filter press 3 can effectively separate the solid and liquid in the slurry, and the separated filtrate enters the third washing liquid receiving tank 4, while the filter cake is sent to the pulping tank 6 for further processing. The two plate-and-frame filter presses designed in parallel allow one device to continue to work while the other device is being maintained, ensuring efficient operation and continuity of the system; the filter cake separated by the plate-and-frame filter press 3 enters the pulping tank 6. During this process, an acetic acid filling pipe 8 is installed on the side wall of the pulping tank to accurately control the amount of acetic acid added to ensure that the filter cake can be fully broken up to form a uniform slurry. The pulping tank 6 is also equipped with an agitator to fully mix the filter cake and acetic acid, improve the fluidity of the filter cake, and facilitate subsequent transportation. The treated slurry is transported to the third crystallizer 1 through the second pump body, and further crystallized and recovered usable substances in the third crystallizer. The pulped slurry is transported to the third crystallizer 1, where it is crystallized to recover valuable components in the slurry. The discharge port of the third crystallizer is connected to the washing port of the pneumatic filter press 2 through a pipeline, and the treated slurry enters the pneumatic filter press for further washing and separation operations. By pre-treating the slurry in the crystallizer, the efficiency of subsequent filter pressing operations can be improved. The pneumatic filter press 2 is used to further wash the filter cake after crystallization to ensure that the residual liquid in the filter cake is fully washed. The washing liquid of the pneumatic filter press comes from the third washing liquid receiving tank 4, thereby reducing the use of fresh water. The pneumatic filter press 2 uses high-pressure pneumatic action to clean the filter cake to ensure that the residual substances in the filter cake are removed as much as possible, thereby improving the separation effect. The filter cake after washing can be used for other purposes or further processing, and the liquid produced by washing is refluxed to the third washing liquid receiving tank 4 again to form a closed-loop system. The filtrate separated by the plate and frame filter press 3 and the pneumatic filter press 2 is collected in the third washing liquid receiving tank 4, temporarily stored in this tank, and used as the circulating washing liquid of the pneumatic filter press. This closed-loop design greatly reduces the demand for fresh water, reduces the consumption of water resources and the cost of system operation. By reusing the filtrate, the device achieves efficient utilization of resources and reduces the discharge of wastewater, which is beneficial to environmental protection.Through the organic combination of the above devices and steps, the whole system forms an efficient slurry processing and recycling cycle. After the slurry is initially stabilized in the buffer tank 7, it is separated into solid and liquid by the plate and frame filter press 3, and then pulped by the pulping tank 6 to improve fluidity, and then enters the third crystallizer 1 for crystallization recovery. The pneumatic filter press 2 further washes the filter cake efficiently, and all the washing liquid and filtrate are collected in the third washing liquid receiving tank 4 to realize the recycling of water resources.

[0056] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An oxidation pneumatic filter press bilge slurry treatment and recycling device, comprising a slurry treatment system, characterized in that: The slurry treatment system comprises a third crystallizer (1), a pneumatic filter press (2), a plate-frame filter press (3), a third washing liquid receiving tank (4), a pulping tank (6) and a buffer tank (7); the pneumatic filter press (2), the plate-frame filter press (3) and the third washing liquid receiving tank (4) are arranged on the upper layer (5); the feed port of the third crystallizer (1) is connected to the discharge port of the pulping tank (6) through a pipeline; the discharge port of the third crystallizer (1) is connected to the pneumatic filter press ( The third washing liquid receiving tank (4) is connected to the washing port of the pneumatic filter press (2) through a pipeline, the feed port of the pulping tank (6) is connected to the discharge port of the plate and frame filter press (3) through a pipeline, the feed port of the third washing liquid receiving tank (4) is connected to the liquid outlet of the plate and frame filter press (3) through a pipeline, the discharge port of the third washing liquid receiving tank (4) is connected to the washing port of the pneumatic filter press (2) through a pipeline, and the feed port and discharge port of the buffer tank (7) are respectively connected to the discharge port of the pneumatic filter press (2) and the feed port of the plate and frame filter press (3) through a pipeline.

2. The oxidation pneumatic filter press bilge slurry treatment and recycling device according to claim 1 is characterized in that: A first pump body is provided between the buffer tank (7) and the plate and frame filter press (3), a second pump body is provided between the plate and frame filter press (3) and the pulping tank (6), and a third pump body is provided between the third crystallizer (1) and the pneumatic filter press (2). Each pump body is used to transport the slurry to each process in sequence, thereby ensuring the flow and pressure stability of the slurry in the system.

3. The oxidation pneumatic filter press bilge slurry treatment and recycling device according to claim 1 is characterized in that: An acetic acid filling pipe (8) is fixedly connected to the side wall of the beating tank (6), and the beating effect of the filter cake is improved by adding acetic acid.

4. The oxidation pneumatic filter press bilge slurry treatment and recycling device according to claim 1 is characterized in that: The buffer tank (7) and the pulping tank (6) are both provided with a stirrer for preventing the slurry from settling and maintaining a uniform distribution of the slurry.

5. The oxidation pneumatic filter press bilge slurry treatment and recycling device according to claim 1 is characterized in that: The buffer tank (7) is provided with a pressure control system to ensure the stability of the pressure of the pneumatic filter press system.

6. A method for treating and recycling slurry from the bottom of a bilge of an oxidizing pneumatic filter press, according to an apparatus for treating and recycling slurry from the bottom of a bilge of an oxidizing pneumatic filter press according to any one of claims 1 to 5, characterized in that: The following steps are involved: S1: introducing the slurry formed on the bottom of the bilge into the buffer tank (7); S2: The buffer tank (7) is equipped with an agitator to prevent material sedimentation and a pressure control system to ensure the stability of the system pressure; S3: The slurry in the buffer tank (7) is transported to the plate and frame filter press (3) by a pump, the pump inlet adopts bottom feeding, and is equipped with a backflow to the buffer tank (7) to prevent the sedimentation of the material; S4: entering the plate and frame filter press (3) for solid-liquid separation, using two plate and frame filter presses (3) in parallel to ensure continuous operation of the system; S5: the filter cake enters a pulping tank (6) for pulping, and after pulping with acetic acid, is transported to the third crystallizer (1) by a pump for recycling; S6: The filtrate enters the third washing liquid receiving tank (4) and is used for washing the filter cake of the pneumatic filter press (2) to reduce the use of fresh water.

7. The method for treating and recycling slurry from the bilge of an oxidative pneumatic filter press according to claim 6, characterized in that: The buffer tank (7) in step S2 maintains the uniformity of the slurry through an agitator to prevent the slurry from settling due to long-term static state.

8. The method for treating and recycling slurry from the bilge of an oxidative pneumatic filter press according to claim 6, characterized in that: In step S4, two plate-frame filter presses (3) are switched in parallel to ensure continuous operation of the plate-frame filter presses and reduce system downtime.

9. The method for treating and recycling slurry from the bilge of an oxidative pneumatic filter press according to claim 6, characterized in that: In step S5, acetic acid is added for pulping to improve the fluidity of the filter cake and the smoothness of pump transportation.

10. The method for treating and recycling slurry from the bilge of an oxidative pneumatic filter press according to claim 6, characterized in that: In step S6, the filter cake of the pneumatic filter press (2) is washed by using the filtrate in the third washing liquid receiving tank (4), so as to reduce the consumption of fresh water and realize the recycling of water resources.

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