A straight-through granule collection recycling system

Abstract

The application discloses a reaction system with a straight-through particle collection recycling function, which comprises a reactor and a particle collector, the particle collector is located outside the reactor, and the reactor is connected with the particle collector through a pipeline; wherein the particle collector comprises a shell and a filter part arranged in the shell; the filter part is surrounded by a filter material and is used for intercepting solid substances; the upper end of the filter part is a feeding end, and the lower end of the filter part is a discharging end; a flushing part is arranged in the filter part and is used for flushing the solid substances intercepted in the filter part. The solid catalyst in the reaction system is effectively separated from the reaction system, and the separated catalyst is flushed and then put into the reaction again. In the flushing process, no liquid substance outside the reaction system needs to be additionally used.

Description

Technical Field

[0001] This invention relates to the fields of chemical production and food processing technology, and in particular to a system for recovering and recycling solids from solid-liquid reaction products. Background Technology

[0002] In chemical production, solid particles are often used as catalysts for the reaction of liquid raw materials in reactors. In food processing, solid substances are also commonly used as active ingredients for the fermentation of liquid raw materials in fermenters or other equipment. These production processes are generally batch processes. After each batch, the solids in the solid-liquid mixture need to be filtered and separated to obtain the liquid product, and the solids are then added back into the reactor for reuse.

[0003] To obtain a pure liquid product, a filter with an automatic backwashing function is generally required. For example, patent application CN208526566U discloses a device for stabilizing the addition of a catalyst through backwashing. Under normal circumstances, the first valve 70 is open, the second valve 71 is open, the third valve 72 is closed, and the fourth valve 73 is closed. The material in reactor 10 reacts with the catalyst. Then, under the action of the second liquid delivery component 61, the mixture of material and catalyst flows through the catalyst filter 20 for filtration. The material flows into the material tank 30, while the catalyst remains in the catalyst filter 20. The material in the material tank 30 is normally transported to the downstream system through the outlet 81. Then, under the action of the first liquid delivery component 41, the material in the material tank flows through the catalyst filter to backwash the filter. The material containing the catalyst flows into the buffer tube to backwash the filtered catalyst.

[0004] However, due to factors such as the solid content of the backwashing medium, the backwashing flow rate, and the reactor capacity, it is impossible to add all the collected solids into the reactor, which in turn leads to insufficient catalyst or active component content in the reactor, affecting the reaction rate or reaction effect. Summary of the Invention

[0005] One objective of this invention is to effectively separate the solid catalyst from the reaction system, and the separated catalyst is rinsed and reintroduced into the reaction without the need for additional liquid substances outside the reaction system during the rinsing process.

[0006] Another object of the present invention is to provide a method for the continuous recycling of solid materials within a solid-liquid mixed reaction system. Using this method, the solid particles filtered out after the reaction can be efficiently flushed into the reactor using the amount of liquid reaction solution.

[0007] To achieve the above objectives, the present invention provides a reaction system comprising: a reactor and a particle collector, wherein the particle collector is located outside the reactor and the reactor and the particle collector are connected by a pipeline; wherein the particle collector includes a shell and a filter section placed inside the shell, the filter section including a cavity surrounded by filter material, the upper end of the filter section being the feed end and the lower end of the filter section being the discharge end; a rinsing component is located inside the filter section for rinsing the solid substances trapped inside the filter section.

[0008] The flushing component of this invention employs a forward flushing method to wash away solid matter trapped on the filter section, allowing the filter section to continue its filtration and separation function. The flushing solution used for forward flushing of solid matter is the reaction liquid itself, allowing the flushed solid matter to enter the reactor along with the reaction liquid for subsequent catalytic reactions. Compared to the backwashing technology of the prior art, this requires higher performance of the flushing solution; the liquid must not contain solid matter, otherwise, solid matter will be trapped on the other side of the filter screen during backwashing. Unlike the backwashing process, this invention uses the liquid flowing out of the reactor for forward flushing of solid matter trapped in the filter. No additional treatment of the reaction liquid is required before flushing, reducing process steps in industrial production and enabling continuous production.

[0009] Using the above-described reaction system, this application provides a method for reusing a solid catalyst, wherein the reaction liquid added to the reactor is repeatedly pumped into a particle collector to flush the solid particles trapped in the filter section.

[0010] For solid-liquid mixed reaction systems (e.g., solid catalysts with liquid reactants), the above method utilizes the reaction liquid in the reactor to forward flush the solid catalyst trapped in the filter section, bringing as much of the trapped solid catalyst as possible back into the reactor for reuse. Compared to existing backwashing methods, this significantly reduces the amount of liquid used to flush the solid catalyst trapped in the filter section and efficiently flushes the vast majority of the trapped solid catalyst back into the reactor for reuse. This reduces process steps and lowers production costs. Attached Figure Description

[0011] Figure 1 This is one implementation method of the reaction system.

[0012] Figure 2 This is a schematic diagram of one embodiment of the ring pipe distributor in Example 1.

[0013] Figure 3 This is a schematic diagram of one embodiment of the flushing component. Detailed Implementation

[0014] The solid-liquid mixing reaction system of this application is described in further detail below. This description does not limit the scope of protection of this application, which is defined by the claims. Certain specific details disclosed provide a comprehensive understanding of the various disclosed embodiments. However, those skilled in the art will recognize that embodiments can be implemented using other materials, etc., without employing one or more of these specific details.

[0015] Unless the context otherwise requires, the terms “comprising” and “including” in the specification and claims shall be understood as open-ended and inclusive, meaning “including, but not limited to”.

[0016] The terms "implementation," "an implementation," "another implementation," or "certain implementations" used in this specification refer to specific features, structures, or characteristics described in relation to the implementation, which are included in at least one implementation. Therefore, "implementation," "an implementation," "another implementation," or "certain implementations" do not necessarily all refer to the same implementation. Furthermore, specific features, structures, or characteristics can be combined in any way within one or more implementations. Each feature disclosed in this specification can be replaced by any alternative feature that provides the same, equivalent, or similar purpose. Therefore, unless otherwise specified, the disclosed features are merely general examples of equivalent or similar features.

[0017] The "solid-liquid mixed reaction system" of this application includes a reaction system in which a solid substance is used as a catalyst and a liquid reactant.

[0018] Especially in solid-liquid mixed reaction systems, the mass relationship between the solid catalyst and the liquid reactants is such that the solid catalyst content is 0.01% to 10 wt%. Within this range, the amount of solid catalyst retained by the filtration section is relatively large. Using the reaction system or method of this application, a small amount (of the amount of liquid reactants) of flushing liquid can effectively strip the catalyst from the filtration section and allow it to enter the reactor. The solid catalyst content is the percentage of solid catalyst to the total mass of the solid-liquid mixture.

[0019] In industrial production, some reaction systems involve the reaction of a solid catalyst with liquid reactants. After the reaction, a filter separates the catalyst from the reaction system through solid-liquid separation. To enable continuous recycling of the solid catalyst and simplify the operation process, the following reaction system is provided.

[0020] A solid-liquid mixing reaction system includes: a reactor and a particle collector, the particle collector being located outside the reactor and the reactor being connected to the particle collector via a pipe; wherein, the particle collector includes a shell and a filter section placed inside the shell, the filter section including a cavity surrounded by filter material, the upper end of the filter section being a feed end and the lower end of the filter section being a discharge end; a rinsing component is located inside the filter section for rinsing the solid material trapped inside the filter section.

[0021] The reactor is used to bring a solid catalyst into contact with a reaction liquid to carry out a chemical reaction. The resulting solid-liquid mixture is then separated into solid and liquid phases by a particle collector (i.e., a filtration device), in which the solid catalyst is collected.

[0022] In some embodiments, the filter section of the particle collector is formed by filter material creating a circumferentially closed cavity around an axis that is substantially perpendicular to the horizontal plane.

[0023] An annular space is formed between the peripheral wall of the filter section, which is made of filter material, and the peripheral wall of the shell. After the reaction, the solid-liquid mixture enters the cavity of the filter section through the upper end. After being intercepted by the filter material, the solid catalyst is retained in the filter section, while the liquid flows into the annular space and is discharged from the particle collector.

[0024] Typically, in certain solid-liquid mixed reaction systems, the particle size of solid catalysts is between 50 μm and 5 mm.

[0025] Multiple filter sections can be installed inside the housing. This can improve filtration efficiency.

[0026] The filter materials constituting the filtration section can be various materials such as Johnson's mesh, sintered metal felt, ceramic membrane, and PP cotton. All of these materials allow liquid substances to flow through while retaining solid particles, achieving solid-liquid separation.

[0027] In some embodiments, the rinsing component is located inside the filter cavity. The rinsing component is a pipe extending from top to bottom along the filter cavity, with multiple nozzles provided on the peripheral wall of the pipe. The nozzles are connected to the internal space and external space of the pipe.

[0028] Preferably, the nozzle has a short tubular structure, and the nozzle is inclined downward from one end connected to the pipe to the other end, with the angle between the nozzle and the pipe controlled at 30-90°. More preferably, the angle between the nozzle and the pipe is controlled at 45-80°.

[0029] In some implementations, the flushing component has a straight pipe of equal diameter with a roughly circular cross-section.

[0030] The short tubular structure is also basically a straight tube of equal diameter with a roughly circular cross-section.

[0031] The ratio of the pipe diameter of the rinsing component to the diameter of the short tubular structure of the nozzle is (2.5-8):1. Preferably, the ratio of the pipe diameter of the rinsing component to the diameter of the short tubular structure of the nozzle is controlled at (3-5):1.

[0032] By setting the pipe diameter ratio of the flushing component's pipes and nozzles, combined with the nozzle's tilt angle, the solid catalyst trapped on the peripheral wall of the filter section is subjected to a downward impact force, making it easily flushed off. Simultaneously, this minimizes damage to the catalyst particle structure, preserving the catalyst's catalytic performance for reuse.

[0033] In some embodiments, multiple nozzles are uniformly arranged along the circumferential direction on the same cross-section of the rinsing component's pipe; preferably, at least four nozzles are arranged.

[0034] The nozzles are arranged in one or more layers from top to bottom along the axial direction of the flushing component's pipe. On different cross-sections of the flushing component's pipe, the nozzles on adjacent cross-sections are staggered.

[0035] The total number of nozzles is determined based on the liquid ejection velocity of 1 to 5 m / s and the flow rate into the flushing components.

[0036] In some embodiments, a loop distributor is provided at the liquid inlet end of the filter section, and multiple nozzles are provided on the loop distributor.

[0037] The solid-liquid mixture discharged from the reactor flows into the filtration section through the nozzle of the loop distributor, which can more evenly trap the solid catalyst on the peripheral wall of the filtration section, making it easier to remove solid particles in the subsequent process.

[0038] Preferably, the ring pipe distributor is a ring-shaped structure formed by pipes.

[0039] Ideally, the cross-section of the filter section is basically circular, and the center line of the loop distributor is basically consistent with the center line of the filter section.

[0040] The nozzles are evenly distributed on the annular distributor, and the nozzles spray downwards.

[0041] The reaction system provided in this application allows for efficient solid-liquid separation of the reacted solid-liquid suspension using a particle collector. Fresh reaction liquid is then used to flush away the retained solid and liquid catalyst, which is simultaneously reintroduced into the reactor to continue the catalytic reaction. Compared to existing solid-liquid separation devices, this system has lower requirements for the flushing liquid, eliminating the need to control the solid content in the flushing liquid and thus removing the additional treatment steps. Furthermore, the reaction liquid within the reactor can be repeatedly pressurized and flushed through the rinsing components to remove the retained solid catalyst. In other words, the amount of reaction liquid used for flushing only needs to meet the reactor's requirements, satisfying both the reaction requirements and effectively removing and reusing the retained catalyst from the filter wall.

[0042] On the other hand, using the above-described reaction system, this application provides a method for reusing a solid catalyst, comprising: 1) a catalytic reaction is carried out in a reactor with fresh reaction liquid and solid catalyst; 2) after the reaction is completed, the product and solid catalyst are discharged from the reactor and flow into the filtration cavity of a particle collector; 3) after solid-liquid separation, the solid catalyst is retained in the filtration cavity, and the separated liquid is discharged from the particle collector; 4) fresh reaction liquid is added to the reactor, and then the fresh reaction liquid in the reactor is sent to the filtration cavity to flush the retained solid catalyst; 5) the flushed solid and liquid catalyst and fresh reaction liquid flow back to the reactor to continue the catalytic reaction, and steps 1)-4) are repeated.

[0043] The fresh reaction solution in this application refers to the reaction solution that does not contain solid particles.

[0044] In some embodiments, in step 4), the fresh reaction liquid in the reactor may be repeatedly fed into the cavity of the filter section until the trapped solid catalyst is sufficiently stripped away. In some embodiments, in step 4), when rinsing the trapped solid catalyst, the rinsing liquid is sprayed from the rinsing component at a velocity of 1 to 5 m / s.

[0045] At this spraying speed, solid particles trapped in the filter section can be washed away efficiently without damaging the structure of the catalyst of this application.

[0046] In some embodiments, in step 5), the reaction liquid discharged from the reactor is used to forward flush the solid catalyst trapped in the filter section, and the content of solid particles contained in the reaction liquid discharged from the reactor is 0.01% to 10 wt%.

[0047] Because the flushing solution containing solid particles in the filter section is used to flush the solid catalyst trapped in the filter section, the flushing effect of the flushing solution is improved. That is, the final flushing effect can be achieved with less circulation flushing time.

[0048] The performance of the catalyst of this application will be further described below with reference to specific embodiments.

[0049] Reference Appendix Figure 1 As shown, a straight-through particle collection and recycling system includes components such as a reactor 1, a particle collector 2, and a suspension circulation pump 3. The reactor is a vertical reaction vessel. The reactor and the particle collector are connected by pipelines.

[0050] like Figure 1 Reactor 1 is a vertical reaction vessel with an outlet 21 at the bottom. The outlet 21 of reactor 1 is connected to the upper part of particle collector 2 via a pipeline, transporting the material in the reactor into particle collector 2. The lower part of particle collector 2 has an opening, which is connected to the top of reactor 1 via a pipeline.

[0051] The particle collector 2 includes a shell and a filter section 4 disposed within the shell. The filter section 4 is a closed cavity formed by filter material along a vertical axis, and the peripheral wall of the filter section 4 and the peripheral wall of the shell form an annular space 9. A rinsing component 5 is disposed within the cavity of the filter section 4. The rinsing component 5 is a straight pipe structure, with one end connected to the opening 20 at the upper end of the shell and the lower end extending into the cavity of the filter section 4. Liquid in the reactor 1 can flow into the rinsing component 5 through the opening 20 via a pipeline.

[0052] One possible arrangement of the flushing component 5 is shown in the attached document. Figure 3 The flushing component 5 also includes a plurality of first nozzles 6 disposed on the straight pipe wall. Each first nozzle is inclined downward toward the extension section from one end of the straight pipe wall, and the angle θ between the first nozzle and the straight pipe wall is 30° to 90°. Multiple layers of first nozzles are disposed in the longitudinal direction of the straight pipe of the flushing component 5; multiple first nozzles are evenly disposed on each layer (i.e., on each cross-section), for example, four first nozzles are disposed on each cross-section of the straight pipe. In order to more effectively and thoroughly flush away solid particles, the multiple first nozzles on adjacent sides are staggered.

[0053] Depending on the actual situation, one or more filter units 4 may be provided.

[0054] In a preferred embodiment, in order to more uniformly trap solid particles on the peripheral wall of the filter section 4 and facilitate subsequent rinsing, the solid-liquid suspension flows into the cavity of the filter section 4 through the ring pipe distributor 7.

[0055] As attached Figure 1-2 As shown, the ring pipe distributor 7 is a ring-shaped structure formed by pipes, and an inlet is provided on the ring pipe. The inlet is connected to the reactor 1 through a pipeline.

[0056] Multiple second nozzles 8 are evenly arranged in the circumferential direction of the loop distributor 7, with the second nozzles 8 generally facing downwards. In a more preferred embodiment, the axial centerline of the loop distributor 7 is approximately the same as the axial centerline of the filter section 4, allowing for more uniform distribution of the mixed suspension on the peripheral wall of the filter section 4. Multiple nozzles 8 are evenly arranged at the lower part of the loop distributor 7, the number of nozzles 8 being determined based on the liquid ejection velocity of 0.5–3 m / s.

[0057] In some embodiments, one or more distributors of various forms, such as ring pipe, tubular, or showerhead type, can be installed below the top opening 13 of reactor 1 to improve the distribution of the suspension of raw materials and solid particles in reactor 1.

[0058] Reactor 1 may be equipped with a stirrer to thoroughly stir the liquid inside reactor 1 and improve the contact between raw materials and solid particles.

[0059] Combined with appendix Figure 1 The reaction process is further described below:

[0060] The top of reactor 1 is equipped with a liquid opening 16 and a solid opening 17. Liquid raw materials and solid particles enter reactor 1 through the top openings 16 and 17 respectively to begin chemical reaction or food fermentation. After the reaction or fermentation is completed, the suspension of product and solid particles is drawn out from the bottom opening 21 of reactor 1, pressurized by suspension circulation pump 3, and sent through shut-off valve 11 to the ring pipe distributor 7 connected to the upper opening 14 of particle collector 2. After entering particle collector 2, the suspension is evenly distributed inside the cavity of filter section 4 through nozzles 8 on ring pipe distributor 7, and under the action of internal and external differential pressure, it passes through filter section 4 and enters the annular space 9 between the shell of particle collector 2 and filter section 4 from the inside out. The solid particles in the suspension are trapped inside the cavity of filter section 4, and the clean product enters reactor 1 through the lower opening 14 of particle collector 2, shut-off valve 12, and top opening 15 of reactor 1. During this process, shut-off valves 10 and 13 are closed. The liquid flowing into reactor 1 can repeat the above steps to enter particle collector 2, where it is filtered and the solid particles in the liquid are retained multiple times until the requirements are met and then discharged from the reaction system.

[0061] After the cleaned product is discharged from reactor 1, the next batch of feed for reaction or fermentation begins. Fresh liquid feed enters reactor 1 through top opening 16. Shut-off valves 11 and 12 are closed, while shut-off valves 10 and 13 are opened. The suspension circulation pump 3 is started, drawing the liquid feed from bottom opening 21 of the reactor and pressurizing it before sending it to the rinsing component 5 connected to top opening 20 of particle collector 2. The feed is sprayed out through nozzles 6 arranged on the rinsing component 5, directly rinsing the interior of the filter section 4, fully soaking and rinsing down the solid particles collected from the previous batch. The feed then enters reactor 1 through bottom opening 18 of particle collector 2, shut-off valve 13, and top opening 19 of reactor 1. The feed and solid particles are thoroughly mixed in reactor 1, and the next batch of reaction or fermentation begins. During the next batch of reaction or fermentation, the suspension circulation pump 3 can be kept running, and the reaction suspension can be circulated between reactor 1 and particle collector 2 through the interior of the filter section 4 and shut-off valve 13.

[0062] Example 1

[0063] reaction process

[0064] This embodiment uses the appendix Figure 1-3 The reaction system shown depicts the oxidation reaction of vinyl sulfite and hydrogen peroxide. The solid catalyst particles are white powder with a particle size of 50 μm. The reactants are vinyl sulfite and hydrogen peroxide, and the product is vinyl sulfate. The reaction is carried out in a 1000 L reactor. During the reaction, the amount of catalyst used is 20 kg, the amount of reaction solution is 900 kg, and the reaction temperature is 30 °C.

[0065] Solid-liquid separation process

[0066] After 2 hours of reaction between vinyl sulfite and hydrogen peroxide under the catalysis of a catalyst, the solid-liquid mixture in the reactor is pumped through a circulating pump into a particle collector for multiple cycles of solid-liquid separation. The reaction system is discharged when the content of solid catalyst in the separated liquid is less than 0.01%.

[0067] The process of forward flushing of solid catalyst trapped in the filter section

[0068] 700L of fresh reaction liquid (i.e., reaction liquid free of solid particles) is introduced into a 1000L reactor. The reaction liquid in the reactor is pumped to a particle collector by a circulating pump to flush away the solid catalyst trapped in the filter section and carry the solid catalyst back into the reactor. A 10m... 3A circulating pump continuously pumps the mixture in the reactor to the Deao particle collector to flush the solid catalyst in the filter section. After 10 minutes of operation, 99% of the solid catalyst trapped in the filter section can be flushed away and carried back into the reactor for repeated catalytic reactions.

[0069] Comparative Example 1

[0070] The reaction process and solid-liquid separation process of Comparative Example 1 are the same as in Example 1. The difference is that this comparative example uses a backwashing process to remove the solid catalyst trapped in the filter section.

[0071] Fresh reaction solution (i.e., reaction solution free of solid particles) is used to wash away solid catalyst particles trapped on the inner wall of the filter section from the outer peripheral wall of the filter section. The fresh reaction solution is pumped at a flow rate of 10 m / s. 3 / h. To flush away 99% of the solid catalyst retained in the filter section, 5000L of fresh reaction solution is required, which exceeds the volume of the reactor.

[0072] Comparative Example 2

[0073] The reaction process and solid-liquid separation process of Comparative Example 2 are the same as in Example 1. The difference is that this comparative example uses a forward flushing process to remove the solid catalyst trapped in the filter section.

[0074] In Comparative Example 2, during the forward flushing of the solid catalyst retained in the filter section, fresh reaction liquid (i.e., reaction liquid free of solid particles) was continuously passed through the flushing unit 5 to forward flush the solid catalyst. After flushing, the catalyst was flushed at a rate of 10m... 3 Pumping the flushing solution at a flow rate of / h takes about 40 minutes to flush away 99% of the solid catalyst trapped in the filter section.

Claims

1. A method for reusing a solid catalyst in an oxidation reaction system of vinyl sulfite and hydrogen peroxide, comprising: 1) Fresh reaction solution and solid catalyst undergo catalytic reaction in the reactor; 2) After the reaction is complete, the product and solid catalyst are discharged from the reactor and flow into the filter cavity of the particle collector; 3) After solid-liquid separation, the solid catalyst is retained in the filter cavity, and the separated liquid is discharged from the particle collector; 4) Fresh reaction liquid is added to the reactor, and then the fresh reaction liquid in the reactor is sent to the flushing component of the filter cavity to flush away the retained solid catalyst. The solid particle content in the reaction liquid discharged from the reactor is 0.01%~10wt%; 5) The flushed solid and liquid catalyst and fresh reaction liquid flow back to the reactor to continue the catalytic reaction, and steps 1)-4) are repeated. The particle collector includes a shell and a filter section placed inside the shell. The filter section is a circumferentially closed cavity formed by filter material around an axis perpendicular to the horizontal plane. The upper end of the filter section is the feed end, and the lower end of the filter section is the discharge end. The rinsing component is located inside the filter cavity. The rinsing component is a pipe extending from top to bottom along the filter cavity, with multiple short tubular nozzles opened on the peripheral wall of the pipe. The nozzle is tilted downwards from one end connected to the pipe to the other, with the angle between the nozzle and the pipe controlled between 45-80°.

2. The method according to claim 1, characterized in that, An annular space is formed between the peripheral wall of the filter section, which is made of filter material, and the peripheral wall of the shell.

3. The method according to claim 1, characterized in that, The flushing components use straight pipes of equal diameter with a circular cross-section. The short tubular structure is also a straight tube of equal diameter with a circular cross-section; The ratio of the pipe diameter of the flushing component to the diameter of the short tubular structure of the nozzle is (2.5-8):

1.

4. The method according to claim 3, characterized in that, The ratio of the pipe diameter of the flushing component to the diameter of the short tubular structure of the nozzle is controlled at (3-5):

1.

5. The method according to any one of claims 1-4, characterized in that, At least four nozzles are evenly arranged along the circumferential direction on the same cross section of the flushing component's pipe.

6. The method according to claim 5, characterized in that, The nozzles are arranged in one or more layers from top to bottom along the axial direction of the flushing component's pipe. On different cross-sections of the flushing component's pipe, the nozzles on adjacent cross-sections are staggered.

7. The method according to any one of claims 1-4, characterized in that, A loop distributor is installed at the liquid inlet end of the filter section, and multiple nozzles are installed on the loop distributor; A ring pipe distributor is a ring-shaped structure formed by pipes.

8. The method according to claim 7, characterized in that, The cross-section of the filter section is circular, and the centerline of the loop distributor is consistent with the centerline of the filter section. The nozzles are evenly distributed on the annular distributor, and the nozzles spray downwards.

9. The method according to any one of claims 1-4, characterized in that, In step 4), when flushing the trapped solid catalyst, the flushing liquid is sprayed out of the flushing component at a speed of 1~5m / s.

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