Recovery system

Abstract

The utility model provides a recovery system which comprises a reactor, an absorption tower, a condenser, a first compressor, a crude product storage tank, a second compressor, a rectifying tower and a gas-liquid separation tank, the top of the reactor is communicated with a first pipeline, the bottom of the absorption tower is communicated with the bottom of the reactor through a second pipeline, and the top of the absorption tower is communicated with the first pipeline through a third pipeline; the condenser is installed on the second pipeline, the first compressor is installed on the third pipeline, the crude product storage tank is communicated with the bottom of the absorption tower through a fourth pipeline and a fifth pipeline, the second compressor is installed on the fifth pipeline, and the middle of the rectifying tower is communicated with the crude product storage tank through a sixth pipeline; the gas-liquid separation tank is communicated with the rectifying tower through at least two eighth pipelines so as to be used for separating rectified materials and realizing reflux of the rectifying tower, and the gas-liquid separation tank is communicated with the crude product storage tank through a ninth pipeline so as to be used for guiding separated gas into the crude product storage tank. The recovery system provided by the utility model is beneficial to improving the raw material utilization rate so as to reduce the production cost.

Description

Technical Field

[0001] The utility model relates to the technical field of gas recovery and utilization, in particular to a recovery system. Background Art

[0002] Allyl acetate is an important fine chemical with a wide range of applications. The primary method for producing allyl acetate worldwide today uses propylene, acetic acid, and oxygen as raw materials, catalyzed by metal Pd, to produce the product. However, due to the low single-pass conversion of propylene (less than 20%) in the allyl acetate production process, the product from the oxidation reactor undergoes condensation and absorption, resulting in a certain amount of unreacted propylene dissolved in the crude allyl acetate. This results in low raw material utilization and, consequently, increased production costs. Utility Model Content

[0003] In order to overcome the deficiencies of the prior art, the present invention aims to provide a recycling system that is beneficial to improving the utilization rate of raw materials and reducing production costs.

[0004] In order to solve the above problems, the technical solutions adopted by the present invention are as follows:

[0005] A recycling system comprising:

[0006] A reactor, wherein the top of the reactor is connected to a first pipe, and the first pipe is used to introduce gas materials into the reactor for reaction;

[0007] an absorption tower, wherein the bottom of the absorption tower is connected to the bottom of the reactor through a second pipeline, and the top of the absorption tower is connected to the first pipeline through a third pipeline;

[0008] a condenser installed on the second pipeline for condensing the product discharged from the reactor;

[0009] a first compressor installed on the third pipeline for pumping the gas in the absorption tower into the reactor;

[0010] a crude product storage tank, connected to the bottom of the absorption tower through a fourth pipe and a fifth pipe, the crude product storage tank being used to hold materials discharged from the absorption tower. When observing the absorption tower, an access point of the fifth pipe is higher than an access point of the fourth pipe;

[0011] a second compressor installed on the fifth pipeline for pumping the flash gas in the crude product storage tank into the absorption tower;

[0012] a distillation tower for rectifying and separating the material discharged from the crude product storage tank, wherein the middle portion of the distillation tower is connected to the crude product storage tank via a sixth pipeline, and a seventh pipeline for draining liquid is provided at the bottom of the distillation tower; and

[0013] The gas-liquid separation tank is connected to the distillation tower through at least two eighth pipes for separating the materials after distillation and realizing the reflux of the distillation tower. The gas-liquid separation tank is connected to the crude product storage tank through a ninth pipe for introducing the separated gas into the crude product storage tank. The bottom of the gas-liquid separation tank is connected to a tenth pipe for discharging part of the separated materials.

[0014] In some possible implementations, the top of the absorption tower is further connected to an eleventh pipeline for feeding absorption liquid, and the absorption liquid is used to absorb uncondensed product vapor.

[0015] In some possible implementations, the reactor, the absorption tower, the crude product storage tank, the distillation tower, and the gas-liquid separation tank are arranged in sequence.

[0016] In some possible implementations, the first compressor is a centrifugal compressor or an axial flow compressor.

[0017] In some possible implementations, the second compressor is a liquid ring compressor, a reciprocating compressor, or a screw compressor.

[0018] In some possible implementations, the reactor is a shell-and-tube reactor.

[0019] Compared with the prior art, the beneficial effects of the present invention are:

[0020] In the present application, through the coordinated cooperation between the reactor, absorption tower, condenser, first compressor, crude product storage tank, second compressor, distillation tower and gas-liquid separation tank, the gas discharged along with the product after the reaction can be separated and recovered into the reactor in multiple steps, thereby helping to improve the utilization rate of raw materials and reduce production costs.

[0021] The present invention will be described in further detail below with reference to the accompanying drawings and specific implementation methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A connection diagram of a recycling system provided in one embodiment of the present application.

[0023] Description of Figure Numbers:

[0024] 100 - Recovery system; 10 - Reactor; 11 - Second pipeline; 12 - First pipeline; 20 - Absorption tower; 21 - Third pipeline; 22 - Fourth pipeline; 23 - Eleventh pipeline; 30 - Condenser; 40 - First compressor; 50 - Crude product storage tank; 51 - Fifth pipeline; 52 - Sixth pipeline; 60 - Second compressor; 70 - Distillation tower; 71 - Eighth pipeline; 72 - Seventh pipeline; 80 - Gas-liquid separation tank; 81 - Ninth pipeline; 83 - Tenth pipeline. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0026] The terms "first", "second", etc. in the specification and claims of this application and the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. It should be noted that when an element is referred to as "fixed to" another element, it can be directly on the other element or there can be an element in the middle. When an element is referred to as "connected to" another element, it can be directly connected to the other element or there can be an element in the middle. When an element is referred to as "set on" another element, it can be set on the other element or there can be an element in the middle.

[0027] Reference Figure 1 One embodiment of the present application provides a recovery system 100. For example, recovery system 100 can be used to produce allyl acetate. Recovery system 100 includes a reactor 10, an absorption tower 20, a condenser 30, a first compressor 40, a crude product storage tank 50, a second compressor 60, a distillation tower 70, and a gas-liquid separator 80.

[0028] The top of reactor 10 is connected with the first pipeline 12, and the first pipeline 12 is used for gaseous material being imported into reactor 10 to react, and taking the production of allyl acetate as an example, propylene, acetic acid, oxygen and inert gas four can be passed into reactor to react, and corresponding catalyst, such as supported PD catalyst, can be provided with in reactor 10. The bottom of absorption tower 20 is connected to the bottom of reactor 10 by second pipeline 11, and the top of absorption tower 20 is connected to the first pipeline 12 by the third pipeline 21, so as to be conducive to improving the miscibility of recovered gas and initial feed gas. Condenser 30 is installed in second pipeline 11, and condenser 30 is used for condensing the product discharged from reactor 10, so that product is passed into absorption tower 20 in the form of liquid, and residual reaction gas and inert gas can be passed into absorption tower 20 in the form of gas. The first compressor 40 is installed in the third pipeline 21, and the first compressor 40 is used for the gas pump in absorption tower 20 into reactor 10, so as to realize the recovery of reaction gas. The crude product storage tank 50 is used to hold the materials discharged from the absorption tower 20. The crude product storage tank 50 is connected to the bottom of the absorption tower 20 through the fourth pipeline 22 and the fifth pipeline 51. When observing the absorption tower 20, the access point of the fifth pipeline 51 is higher than the access point of the fourth pipeline 22. Exemplarily, the access point of the fifth pipeline 51 can be above the liquid phase space at the bottom of the tower and below the filler in the absorption tower. Exemplarily, both the fourth pipeline 22 and the fifth pipeline 51 can be connected to the top of the crude product storage tank 50. The second compressor 60 is installed on the fifth pipeline 51. The second compressor 60 is used to pump the flash gas in the crude product storage tank 50 into the absorption tower 20. This part of the gas is also pumped by the first compressor 40 to react in the reactor 10, thereby further recovering the gas.

[0029] The distillation tower 70 is used to distill and separate the materials discharged from the crude product storage tank 50. The middle part of the distillation tower 70 is connected to the crude product storage tank 50 through the sixth pipe 52. For example, it can be connected to the bottom of the crude product storage tank 50. The bottom of the distillation tower 70 is provided with a seventh pipe 72 for draining. The gas-liquid separator 80 is connected to the distillation tower 70 through at least two eighth pipes 71 (two eighth pipes 71 are shown in the figure) for separating the distilled materials and realizing the reflux of the distillation tower 70. The gas-liquid separator 80 is connected to the crude product storage tank 50 through the ninth pipe 81 for introducing the separated gas into the crude product storage tank 50. For example, the gas-liquid separator 80 can be connected to the top of the crude product storage tank 50 through the ninth pipe 81, so that the gas separated by the gas-liquid separator 80 is pumped into the reactor 10 through the first compressor 40 and the second compressor 60, thereby realizing further recovery of the gas. The bottom of the gas-liquid separator 80 is connected with a tenth pipe 83 to discharge part of the separated materials.

[0030] During specific operation, the reactants are introduced into the reactor 10 for reaction. The materials in the reactor 10 are condensed by the condenser 30 and then flow into the absorption tower 20. The gas in the absorption tower 20 is pumped into the reactor 10 for recycling by the first compressor 40, and the materials in the absorption tower 20 are discharged into the crude product storage tank 50. During this period, the flashed gas is pumped into the absorption tower 20 by the second compressor 60 and further pumped into the reactor 10 for recycling by the first compressor 40. The materials discharged from the crude product storage tank 50 are distilled in the distillation tower 70 and then introduced into the gas-liquid separation tank 80 for treatment, so that the gas dissolved in the product overflows and is guided into the crude product storage tank 50, so that it can be pumped into the reactor 10 by the first compressor 40 and the second compressor 60, thereby realizing gas recovery.

[0031] In the present application, through the coordinated cooperation between the reactor 10, the absorption tower 20, the condenser 30, the first compressor 40, the crude product storage tank 50, the second compressor 60, the distillation tower 70 and the gas-liquid separation tank 80, the gas discharged along with the product after the reaction can be separated and recovered into the reactor 10 in multiple steps, thereby helping to improve the utilization rate of raw materials and reduce production costs.

[0032] In some embodiments, the top of the absorption tower 20 is further connected to an eleventh pipe 23 for feeding an absorption liquid. The absorption liquid is used to absorb uncondensed product vapor, thereby reducing the possibility of product vapor being pumped into the reactor 10, thereby improving the reaction conversion efficiency in the reactor 10. For example, the absorption liquid can be an aqueous acetic acid solution. At this point, the absorption liquid and the product liquid are passed together into the distillation tower 70 for distillation treatment, thereby separating the absorption liquid and the product.

[0033] In some embodiments, the reactor 10 , the absorption tower 20 , the crude product storage tank 50 , the distillation tower 70 , and the gas-liquid separation tank 80 are arranged in sequence, thereby facilitating reduction of the layout space of the recovery system 100 .

[0034] In some embodiments, the first compressor 40 is a centrifugal compressor or an axial compressor.

[0035] In some embodiments, the second compressor 60 is a liquid ring compressor, a reciprocating compressor or a screw compressor. The types of the first compressor 40 and the second compressor 60 are selected to have advantages of low equipment cost and high pumping efficiency, thereby further reducing production costs.

[0036] In some embodiments, the reactor 10 is a shell-and-tube reactor, which has the advantages of good heat transfer performance and good mixing performance.

[0037] In another embodiment, a tank reactor, a tower reactor or a jet reactor can be selected according to the reaction type.

[0038] For example, the absorption tower 20 may be a packed tower, a plate tower or a valve tower.

[0039] The above-mentioned embodiments are only preferred embodiments of the present invention and cannot be used to limit the scope of protection of the present invention. Any non-substantial changes and replacements made by technicians in this field on the basis of the present invention fall within the scope of protection required by the present invention.

Claims

1. A recycling system, characterized in that: include: A reactor, wherein the top of the reactor is connected to a first pipe, and the first pipe is used to introduce gas materials into the reactor for reaction; an absorption tower, wherein the bottom of the absorption tower is connected to the bottom of the reactor through a second pipeline, and the top of the absorption tower is connected to the first pipeline through a third pipeline; a condenser installed on the second pipeline for condensing the product discharged from the reactor; a first compressor installed on the third pipeline for pumping the gas in the absorption tower into the reactor; a crude product storage tank, connected to the bottom of the absorption tower through a fourth pipe and a fifth pipe, the crude product storage tank being used to hold materials discharged from the absorption tower. When observing the absorption tower, an access point of the fifth pipe is higher than an access point of the fourth pipe; a second compressor installed on the fifth pipeline for pumping the flash gas in the crude product storage tank into the absorption tower; a distillation tower for rectifying and separating the material discharged from the crude product storage tank, wherein the middle portion of the distillation tower is connected to the crude product storage tank via a sixth pipeline, and a seventh pipeline for draining liquid is provided at the bottom of the distillation tower; and The gas-liquid separation tank is connected to the distillation tower through at least two eighth pipes for separating the materials after distillation and realizing the reflux of the distillation tower. The gas-liquid separation tank is connected to the crude product storage tank through a ninth pipe for introducing the separated gas into the crude product storage tank. The bottom of the gas-liquid separation tank is connected to a tenth pipe for discharging part of the separated materials.

2. The recycling system according to claim 1, wherein: The top of the absorption tower is also connected to an eleventh pipeline for feeding absorption liquid, and the absorption liquid is used to absorb uncondensed product vapor.

3. The recycling system according to claim 1, wherein: The reactor, the absorption tower, the crude product storage tank, the distillation tower and the gas-liquid separation tank are arranged in sequence.

4. The recycling system according to claim 1, wherein: The first compressor is a centrifugal compressor or an axial flow compressor.

5. The recycling system according to claim 1, wherein: The second compressor is a liquid ring compressor, a reciprocating compressor or a screw compressor.

6. The recycling system according to claim 1, wherein: The reactor is a tubular reactor.

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