Preparation system of oxygen-deficient nitrogen

Abstract

The utility model discloses a preparation system of oxygen-deficient nitrogen, which comprises a buffer tank as an oxygen-deficient nitrogen tank; a gas inlet of the buffer tank is connected with a gas mixer, a high-purity nitrogen inlet pipe and a compressed air inlet pipe are respectively connected with a gas inlet of the gas mixer, and the two gases enter the oxygen-poor nitrogen tank after being mixed in the gas mixer. According to the oxygen-deficient nitrogen preparation system provided by the utility model, high-purity nitrogen and compressed air provided by a chemical industry park can be used as raw material gases, and the high-purity nitrogen and the compressed air respectively enter the gas mixer in proportion to be mixed and then enter the oxygen-deficient nitrogen tank, so that the oxygen-deficient nitrogen with required concentration is continuously provided for production.

Description

TECHNICAL FIELD

[0001] The utility model relates to the preparation system of oxygen -deficient nitrogen. BACKGROUND

[0002] The production and storage process of acrylic acid and acrylate monomer generally needs to provide a certain amount of oxygen as an inhibitor. The main mechanism of oxygen as an inhibitor is that it can capture free radicals. In the free radical polymerization reaction, free radicals are initiators and chain growth agents of polymerization reaction. However, when oxygen exists, it will react with free radicals to generate products such as peroxide radicals or hydrogen peroxide, thereby consuming free radicals and preventing the polymerization reaction.

[0003] However, too high oxygen concentration makes the solvent in the production process within a certain space in the explosion limit range, which will bring great safety risk in the production process of acrylic acid and acrylate, so oxygen-deficient nitrogen with an oxygen content of 5-8% is needed for the production of acrylic acid and acrylate monomer.

[0004] The domestic process for producing acrylic acid and acrylate monomer generally uses pressure swing adsorption technology PSA to prepare oxygen-deficient nitrogen. The principle is to separate gas mixture by using the difference in the "adsorption" performance of molecular sieves for different gas molecules. It uses air as raw material and uses a high-performance and high-selectivity solid adsorbent to separate nitrogen and oxygen in air. The equipment cost is high, and the maintenance and operation energy consumption cost is also high. Moreover, the unstable oxygen content leads to frequent polymerization of process materials. UTILITY MODEL CONTENTS

[0005] The utility model provides a kind of preparation system of oxygen-deficient nitrogen, continuously provides the required concentration of oxygen-deficient nitrogen for the production of acrylic acid and acrylate monomer.

[0006] Specifically, the utility model provides the technical scheme as follows: the preparation system of oxygen-deficient nitrogen includes buffer tank, as oxygen-deficient nitrogen tank, gas inlet is connected with gas mixer, high-purity nitrogen gas inlet pipe and compressed air inlet pipe are connected with the gas inlet of gas mixer respectively, high-purity nitrogen gas and compressed air are mixed into gas mixer according to proportion and then enter oxygen-deficient nitrogen tank, continuously provide the required concentration of oxygen-deficient nitrogen for production.

[0007] Flow meter and automatic regulating valve are respectively arranged on high-purity nitrogen gas inlet pipe and compressed air inlet pipe to monitor raw material gas inlet flow and adjust gas inlet quantity.

[0008] The on-line oxygen content analyzer is arranged on the top of the oxygen-poor nitrogen tank, and is connected with the automatic adjusting valve on the compressed air inlet pipe, the on-line oxygen content analyzer analyzes the oxygen content of the gas in the tank, and controls the automatic adjusting valve on the compressed air inlet pipe, and the automatic adjusting valve automatically adjusts the flow of the inlet compressed air according to the set oxygen content.

[0009] The pressure remote control device is arranged on the top of the oxygen-poor nitrogen tank, and controls the automatic adjusting valve of the nitrogen inlet pipe, and the pressure remote control device automatically adjusts the flow of the inlet nitrogen according to the set pressure.

[0010] The drainage pipeline is arranged at the bottom of the oxygen-poor nitrogen tank, and the oxygen-poor nitrogen tank is drained regularly to ensure the dryness of the oxygen-poor nitrogen.

[0011] The emergency cut-off valve is arranged at the top outlet of the oxygen-poor nitrogen tank, and the emergency cut-off valve and the on-line oxygen content monitor form interlocking control, when the oxygen content is greater than or equal to 8%, the emergency interlocking cut-off is realized to avoid the formation of explosive gas in the reaction system.

[0012] The flow monitor is arranged at the top outlet of the oxygen-poor nitrogen tank to ensure the flow supply of the oxygen-poor nitrogen user, and timely alarm is realized when low flow occurs.

[0013] The one-way valve is arranged at the top outlet of the oxygen-poor nitrogen tank to prevent the material of the gas system from being reversely connected to the oxygen-poor tank.

[0014] Beneficial effects:

[0015] 1. The utility model provides a preparation system of oxygen-poor nitrogen, including buffer tank, as oxygen-poor nitrogen tank, its gas inlet connects gas mixer, high purity nitrogen inlet pipe and compressed air inlet pipe enter gas mixer in proportion respectively after mixing and enter oxygen-poor nitrogen tank, and the oxygen-poor nitrogen of required concentration is provided for production continuously.

[0016] 2. The on-line oxygen content analyzer is arranged on the top of the oxygen-poor nitrogen tank of the utility model, the oxygen content of the gas in the tank is analyzed, the automatic adjusting valve on the compressed air inlet pipe is controlled, and the flow of the inlet compressed air is automatically adjusted according to the set oxygen content.

[0017] 3. The pressure remote control device is arranged on the top of the oxygen-poor nitrogen tank of the utility model, and the automatic adjusting valve of the nitrogen inlet pipe is controlled by the pressure remote control device, and the flow of the inlet nitrogen is automatically adjusted according to the set pressure.

[0018] 4. The emergency cut-off valve is arranged at the top outlet of the oxygen-poor nitrogen tank of the utility model, and the emergency cut-off valve and the on-line oxygen content monitor form interlocking control, when the oxygen content is greater than or equal to 8%, the emergency interlocking cut-off is realized to avoid the formation of explosive gas in the reaction system.

[0019] 5. The flow monitor is arranged at the top outlet of the oxygen-poor nitrogen tank of the utility model to ensure the flow supply of the oxygen-poor nitrogen user, and timely alarm is realized when low flow occurs.

[0020] 6. The top outlet of the oxygen-deficient nitrogen tank of this utility model is equipped with a one-way valve to prevent the material from the gas system from flowing back into the oxygen-deficient tank. Attached Figure Description

[0021] Figure 1 This is a structural schematic diagram of an embodiment of the present utility model. Specific Implementation

[0022] like Figure 1 The oxygen-deficient nitrogen gas preparation system shown is an embodiment of this utility model. The system includes a buffer tank, serving as the oxygen-deficient nitrogen gas tank 1. The inlet of the oxygen-deficient nitrogen gas tank 1 is connected to a gas mixer 2. A high-purity nitrogen gas inlet pipe 3 and a compressed air inlet pipe 4 are respectively connected to the inlet of the gas mixer 2. Automatic regulating valves 5 and 6 are respectively installed on the high-purity nitrogen gas inlet pipe 3 and the compressed air inlet pipe 4. The high-purity nitrogen and compressed air are mixed in the gas mixer 2 after the inlet ratio is adjusted by the regulating valves 5 and 6, and then continuously supplied with the required concentration of oxygen-deficient nitrogen gas for production.

[0023] Flow meters 7 and 8 are respectively installed on the high-purity nitrogen inlet pipe 3 and the compressed air inlet pipe 4 to monitor the inlet flow rate of the raw material gas.

[0024] An online oxygen content analyzer 9 is installed on the top of the oxygen-deficient nitrogen tank 1. It is connected to the automatic regulating valve 6 on the compressed air inlet pipe 4. The online oxygen content analyzer 9 analyzes the oxygen content of the gas in the tank and controls the automatic regulating valve 6 on the compressed air inlet pipe 4 to automatically adjust the intake compressed air flow rate according to the set oxygen content.

[0025] A pressure remote control device 10 is installed on the top of the nitrogen-deficient gas tank 1. The pressure remote control device 10 controls the automatic regulating valve 5 of the nitrogen inlet pipe 3 to automatically adjust the nitrogen inlet flow rate according to the set pressure.

[0026] A drain line 11 is installed at the bottom of the oxygen-deficient nitrogen tank 1 to drain the gas regularly and ensure that the oxygen-deficient gas is dry.

[0027] An emergency shut-off valve 12 is installed at the top outlet of the oxygen-deficient nitrogen tank 1. The emergency shut-off valve 12 is interlocked with the online oxygen content monitor 9. When the oxygen content is ≥8%, the emergency interlock shut-off is activated to prevent the formation of explosive gas in the reaction system.

[0028] A flow monitor 13 is installed at the top outlet of the oxygen-deficient nitrogen tank 1 to ensure the flow supply for oxygen-deficient users and to promptly alarm when low flow occurs.

[0029] The top outlet of the oxygen-deficient nitrogen tank 1 is equipped with a one-way valve 14 to prevent material from the gas system from flowing back into the oxygen-deficient nitrogen tank 1.

Claims

1. A system for producing oxygen-depleted nitrogen gas, characterized by, The application relates to a nitrogen gas buffer tank, which is used as an oxygen-poor nitrogen gas tank; an air inlet of the buffer tank is connected with a gas mixer; a high-purity nitrogen gas inlet pipe and a compressed air inlet pipe are respectively connected with air inlets of the gas mixer.

2. The system for producing oxygen-lean nitrogen gas according to claim 1, characterized by, Flow meters and automatic adjusting valves are respectively arranged on the high-purity nitrogen gas inlet pipe and the compressed air inlet pipe.

3. The system for producing oxygen-lean nitrogen gas according to claim 2, characterized by, An online oxygen content analyzer is arranged on the top of the oxygen-poor nitrogen gas tank and is connected with the automatic adjusting valve on the compressed air inlet pipe.

4. The system for producing oxygen-lean nitrogen gas according to claim 2, characterized by, A pressure remote control device is arranged on the top of the oxygen-poor nitrogen gas tank and is connected with the automatic adjusting valve on the nitrogen gas inlet pipe.

5. The system for producing oxygen-lean nitrogen gas according to claim 1, characterized by, A drain pipeline is arranged at the bottom of the oxygen-poor nitrogen gas tank.

6. The system for producing oxygen-lean nitrogen gas according to claim 1, characterized by, An emergency cut-off valve is arranged at the top outlet of the oxygen-poor nitrogen gas tank and forms interlocking control with the online oxygen content monitoring instrument.

7. The system for producing oxygen-lean nitrogen gas according to claim 1, characterized by, A flow monitoring instrument is arranged at the top outlet of the oxygen-poor nitrogen gas tank.

8. The system for producing oxygen-lean nitrogen gas according to claim 1, characterized by, A one-way valve is arranged at the top outlet of the oxygen-poor nitrogen gas tank.

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