Oxidized tail gas recycling and nitrogen making system

Abstract

The utility model discloses an oxidized tail gas recovery nitrogen-making system, which is characterized in that an oxidation tower is connected with an oxidized tail gas gas-liquid separator through an oxidized tail gas cooler, the oxidized tail gas gas-liquid separator is connected with a condenser through an expansion valve, and the condenser is connected with a tail gas adsorption treatment system; the tail gas adsorption treatment system is connected with a nitrogen making unit through a nitrogen making machine front buffer tank; and the nitrogen making unit is connected with a nitrogen storage tank. According to the device, the oxidation tail gas is recycled, gas resources are used for preparing nitrogen, pressure energy is used for power generation, the treatment cost of the oxidation tail gas is reduced, and resource utilization is achieved.

Description

TECHNICAL FIELD

[0001] The utility model belongs to hydrogen peroxide production technical field, more particularly in a kind of recovery of oxidized tail gas nitrogen system. BACKGROUND

[0002] At present, most of the hydrogen peroxide production devices in China use anthraquinone fixed bed process, which uses anthraquinone as a carrier, and several of C9-C10 heavy aromatic hydrocarbons, trioctyl phosphate, ortho-methylcyclohexyl acetate and tetrabutyl urea are used as solvents to prepare working solution, and industrial grade hydrogen peroxide product is obtained through hydrogenation, oxidation, extraction, purification and other processes.

[0003] Nitrogen generator is mainly divided into two types: membrane separation nitrogen generator and pressure swing adsorption nitrogen generator. Membrane separation nitrogen generator uses the difference in permeability of different gases to realize the separation of nitrogen; pressure swing adsorption nitrogen generator uses the adsorption and desorption characteristics of molecular sieve to realize the separation and purification of nitrogen. Pressure swing adsorption nitrogen generator is mainly used in hydrogen peroxide production, and its process is as follows:

[0004] (1) Air purification: remove water vapor, carbon dioxide and other impurities in the input air through filter;

[0005] (2) Compression and cooling: compress and cool the purified air to reach the adsorption temperature of molecular sieve;

[0006] (3) Adsorption and desorption: use the adsorption characteristics of molecular sieve to adsorb nitrogen on molecular sieve at high pressure, and discharge the remaining oxygen and other gases. Then, nitrogen is desorbed from molecular sieve by reducing pressure;

[0007] (4) Nitrogen purification: purify the desorbed nitrogen through a series of steps such as heating, pressurizing or depressurizing, etc. to obtain high-purity nitrogen;

[0008] (5) Product output: store or output the purified nitrogen for use.

[0009] Chinese patent CN217961985U discloses a hydrogen peroxide oxidation tail gas separation and recovery system, which comprises an extraction tower and an oxidation tail gas cooler, a separation buffer tank, a cyclone separator and a coalescer connected in sequence; the oxidation tail gas cooler is connected with the oxidation tail gas outlet of the oxidation tower, so that the oxidation tail gas discharged from the oxidation tower is cooled by the oxidation tail gas cooler and then enters the separation buffer tank, cyclone separator and coalescer in sequence for gas-liquid separation, which is beneficial to completely separate and recover organic components in oxidation tail gas, and reduce the organic content and VOCs content in oxidation tail gas emission.

[0010] The Chinese patent CN221580142U discloses a hydrogen peroxide production oxidation tail gas recycling device, which comprises a box body, a separation cylinder arranged in the box body and arranged vertically, and spiral blades spirally extending around the separation cylinder, and solves the problem of low condensation efficiency of the cooler in the prior art.

[0011] However, the prior art mainly solves the problem of gas-liquid separation in the oxidation tail gas, and does not effectively realize the resource utilization of the gas components and the working liquid. The residual aromatic hydrocarbon organic matter in the oxidation tail gas is directly discharged, which will cause serious environmental pollution, and even cause central nervous system dysfunction, and even death in severe cases. Therefore, the recycling of the oxidation tail gas is not only a necessary means for saving resources, but also a necessary means for reducing environmental pollution and improving production safety. SUMMARY

[0012] In view of the above technical problems, the utility model provides a kind of recycling of oxidation tail gas nitrogen production system, realizes the recycling of oxidation tail gas, wherein gas resource is used to prepare nitrogen, and pressure energy is used to generate electricity, reduce the processing cost of oxidation tail gas, and realize resource utilization.

[0013] In order to achieve the above purpose, the utility model provides a kind of recycling of oxidation tail gas nitrogen production system, oxidation tower is connected with oxidation tail gas cooler and oxidation tail gas liquid separator, oxidation tail gas liquid separator is connected with condenser through expansion valve, condenser is connected with tail gas adsorption treatment system, tail gas adsorption treatment system is connected with nitrogen making machine group through nitrogen making machine front buffer tank, and nitrogen making machine group is connected with nitrogen storage tank.

[0014] Preferably, the oxidation tail gas liquid separator is connected with the nitrogen making machine front buffer tank pipeline, and the nitrogen making machine front buffer tank is connected with the emptying valve pipeline.

[0015] Preferably, the oxidation tail gas cooler is connected with the cooling water storage tank in circulation.

[0016] Preferably, the oxidation tail gas liquid separator, the condenser and the tail gas adsorption treatment system are respectively connected with the working liquid storage tank pipeline.

[0017] Preferably, the expansion valve is connected with the gear box and the coupling, the coupling is connected with the asynchronous motor, and the asynchronous motor is connected with the storage battery.

[0018] Preferably, a demister is arranged in the oxidation tail gas liquid separator, and the gas inlet pipe is provided with a downward elbow.

[0019] Further preferably, the downward elbow extends into the inner bottom of the oxidation tail gas liquid separator.

[0020] Preferably, the gas inlet pipe of the nitrogen making machine front buffer tank is provided with a downward elbow, and the downward elbow extends into the inner bottom of the nitrogen making machine front buffer tank.

[0021] The present application has the advantages of:

[0022] 1. The oxidation tail gas in the hydrogen peroxide production device is recycled and cooled, and then used to produce nitrogen by a nitrogen production unit, so that the resource utilization rate and the consumption of the catalyst in the nitrogen production unit are improved, and the treatment difficulty of the oxidation tail gas is reduced.

[0023] 2. The oxidation tail gas is cooled and gas-liquid separated in multiple processes by using an oxidation tail gas cooler, an oxidation tail gas gas-liquid separator, an expansion valve, a condenser and a tail washing adsorption treatment system, so that the working liquid remaining in the oxidation tail gas is completely separated from the oxidation tail gas, and the separated working liquid can be recycled, the utilization rate of the working liquid is improved, the resource waste is reduced, and the working liquid can avoid affecting the nitrogen production effect.

[0024] 3. The pressure of the oxidation tail gas in the expansion valve can be converted into mechanical energy to generate electricity, so that the pressure is recovered while refrigeration is realized, the tail gas pressure energy is effectively recycled and reused, and the energy waste of the tail gas is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0025] Fig. 1 It is a schematic diagram of the whole connection of the present application.

[0026] Fig. 2 It is a sectional view of the oxidation tail gas gas-liquid separator.

[0027] Fig. 3 It is a sectional view of the nitrogen production machine front buffer tank.

[0028] In the figure, 1 is an oxidation tower, 2 is an oxidation tail gas cooler, 3 is a cooling water storage tank, 4 is an oxidation tail gas gas-liquid separator, 5 is a working liquid storage tank, 6 is an expansion valve, 7 is a condenser, 8 is a tail gas adsorption treatment system, 9 is a nitrogen production machine front buffer tank, 10 is an emptying valve, 11 is a nitrogen production unit, 12 is a nitrogen storage tank, 13 is a gear box, 14 is a coupling, 15 is an asynchronous motor, 16 is a storage battery, and 17 is a demister. DETAILED DESCRIPTION

[0029] The technical scheme of the present application will be further explained and described below in combination with the drawings and specific embodiments. It should be noted that the following embodiments are only preferred embodiments of the present application, and should not be understood as limiting the present application. The protection scope of the present application should be based on the content recorded in the claims. The modifications and replacements of the technical scheme of the present application made by those skilled in the art without creative labor fall within the protection scope of the present application.

[0030] Embodiment 1

[0031] As Figs. 1-3As shown, a nitrogen generation system for recovering oxidation tail gas is described. The top of an oxidation tower 1 is connected to an oxidation tail gas cooler 2 and an oxidation tail gas gas-liquid separator 4. The oxidation tail gas gas-liquid separator 4 is connected to a condenser 7 via an expansion valve 6. The condenser 7 is connected to a tail gas adsorption treatment system 8. The tail gas adsorption treatment system 8 is connected to a nitrogen generator unit 11 via a nitrogen generator pre-buffer tank 9. The nitrogen generator unit 11 is connected to a nitrogen storage tank 12. Air reacts in the hydrogen peroxide production unit—oxidation tower 1—consuming oxygen to become oxidation tail gas. The oxidation tail gas is discharged from the top of oxidation tower 1 and enters the oxidation tail gas cooler 2 to be cooled to 30-40°C. Then, it undergoes expansion and cooling via the expansion valve 6 and condenser 7 to obtain oxidation tail gas at 5-15°C. This is then transported to the tail gas adsorption treatment system 8 for adsorption, further separating the oxidation tail gas from the working fluid. The separated oxidation tail gas is then transported to the nitrogen generator buffer tank 9 for buffering. After adjusting the gas flow rate, it is sent to the nitrogen generator unit 11 for nitrogen generation. The generated nitrogen is stored in the nitrogen storage tank 12.

[0032] Preferably, the oxidation tail gas gas-liquid separator 4 is connected to the nitrogen generator pre-buffer tank 9 via pipeline, allowing the oxidation tail gas processed in the oxidation tail gas gas-liquid separator 4 to be directly transported to the nitrogen generator pre-buffer tank 9 for buffering and regulating gas flow; the nitrogen generator pre-buffer tank 9 is connected to the vent valve 10 via pipeline, allowing for convenient regulation of gas flow by controlling the opening or closing of the vent valve. This facilitates the maintenance of various systems.

[0033] Preferably, the oxidation tail gas cooler 2 is circulatedly connected to the cooling water storage tank 3, and the cooling water stored in the cooling water storage tank 3 is circulated to the oxidation tail gas cooler 2 for heat exchange, thereby achieving cooling and temperature reduction of the oxidation tail gas.

[0034] Preferably, the oxidation tail gas gas-liquid separator 4, condenser 7 and tail gas adsorption treatment system 8 are respectively connected to the working fluid storage tank 5 via pipelines, so that the working fluid separated from the oxidation tail gas gas-liquid separator 4, condenser 7 and tail gas adsorption treatment system 8 can be discharged and temporarily stored in the working fluid storage tank 5 for recycling and to improve resource utilization.

[0035] Preferably, the expansion valve 6 is connected to the coupling 14 via the gearbox 13, the coupling 14 is connected to the asynchronous motor 15, and the asynchronous motor 15 is connected to the battery 16. The exhaust gas pressure in the expansion valve 6 is converted into mechanical energy, which is then transmitted to the asynchronous motor 15 to generate electricity. The generated electricity is temporarily stored in the battery 16 and then connected to the power grid for use.

[0036] Preferably, the oxidation tail gas gas-liquid separator 4 is equipped with a demister 17 and the air inlet pipe is provided with a downward bend, which improves the efficiency of oxidation tail gas gas-liquid separation.

[0037] Further preferably, the downward bend extends into the inner bottom of the oxidized tail gas gas-liquid separator 4, so that gas-liquid separation is more complete.

[0038] Preferably, the gas inlet pipe of the nitrogen generator front buffer tank 9 is provided with a downward bend, which extends into the inner bottom of the nitrogen generator front buffer tank 9, so that gas-liquid separation is more complete.

Claims

1. A nitrogen recovery system for oxidized tail gas, characterized by: The oxidation tower (1) is connected with the oxidation tail gas cooler (2) and the oxidation tail gas gas-liquid separator (4), the oxidation tail gas gas-liquid separator (4) is connected with the condenser (7) through the expansion valve (6), the condenser (7) is connected with the tail gas adsorption treatment system (8), the tail gas adsorption treatment system (8) is connected with the nitrogen making machine group (11) through the nitrogen making machine front buffer tank (9), the nitrogen making machine group (11) is connected with the nitrogen storage tank (12).

2. The nitrogen generation system for recycling oxidized tail gas according to claim 1, characterized in that: The oxidation tail gas gas-liquid separator (4) is connected with the nitrogen making machine front buffer tank (9) through pipelines, and the nitrogen making machine front buffer tank (9) is connected with the emptying valve (10) through pipelines.

3. The nitrogen generation system for recycling oxidized tail gas according to claim 1, characterized in that: The oxidation tail gas cooler (2) is connected with the cooling water storage tank (3) in circulation.

4. The nitrogen generation system for recycling oxidized tail gas according to claim 1, characterized in that: The oxidation tail gas gas-liquid separator (4), the condenser (7) and the tail gas adsorption treatment system (8) are respectively connected with the working liquid storage tank (5) through pipelines.

5. The nitrogen generation system for recycling oxidized tail gas according to claim 1, characterized in that: The expansion valve (6) is connected with the coupling (14) through the gear box (13), the coupling (14) is connected with the asynchronous motor (15), and the asynchronous motor (15) is connected with the storage battery (16).

6. A nitrogen generation system for recovering an oxidation tail gas according to any one of claims 1, 2 and 4, characterized in that: The oxidation tail gas gas-liquid separator (4) is provided with a demister (17), and the gas inlet pipe is provided with a downward elbow.

7. The nitrogen generation system for recycling oxidized tail gas according to claim 6, characterized in that: The downward elbow extends into the inner bottom of the oxidation tail gas gas-liquid separator (4).

8. The nitrogen generation system for recycling oxidized tail gas according to claim 1 or 2, characterized in that: The gas inlet pipe of the nitrogen making machine front buffer tank (9) is provided with a downward elbow, and the downward elbow extends into the inner bottom of the nitrogen making machine front buffer tank (9).

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