PSA series nitrogen machine operating instructions

1. Use and scope of use

Nitrogen is widely used in petroleum, chemical, food, electronics, metallurgy, medicine and other industries. Air separation nitrogen plants provide nitrogen for a variety of equipment in these industries. Such as metal sintering, laser drilling protective gas, cleaning and gas replacement of petroleum and chemical pipeline equipment, gas preservation and nitrogen filled packaging in the food industry, nitrogen protection of semiconductor devices in the electronics industry, injection nitrogen filled in the pharmaceutical industry and other departments requiring nitrogen.

Ordinary nitrogen produced by PSA series air separation nitrogen equipment can be used as a protective gas in various industries.



Two, PSA series air separation nitrogen machine main specifications and technical parameters are as follows:

Main specifications and parameters

Note: Nitrogen production - cubic meters/hour

Third, working principle and structure

The air separation nitrogen production equipment is a device that extracts nitrogen from the air by using carbon molecular sieve on the principle of pressure swing adsorption.

The adsorption tank of the pressure swing adsorption nitrogen machine, when the pressure is high, the carbon molecular sieve adsorbs the oxygen in the air, and the nitrogen that is not easy to be adsorbed becomes the product; At low pressure, oxygen is desorbed from the carbon molecular sieve. Using the change in pressure, the required nitrogen can be effectively separated from the air.

Main features of pressure swing adsorption nitrogen production device:

The equipment is simple, small size, and the cost of nitrogen production is low.

Convenient operation, automatic program control, low operation and maintenance costs.

The equipment is made of two tower structure, using atmospheric pressure desorption process. The gas production of air separation nitrogen production equipment is inversely proportional to the purity. The purity of nitrogen decreases when gas production is high. On the contrary, the purity of nitrogen increases when the gas volume is reduced. Users can choose the right nitrogen gas production and purity according to their needs.

The control system of the equipment adopts PLC program controller to control the valve action.



After the air is compressed by the air compressor, after drying and dusting, it enters the left adsorption tank through the left suction air valve. The pressure of the tank rises, the oxygen molecules in the compressed air are adsorbed by carbon molecular sieve, and the unadsorbed nitrogen passes through the adsorption bed and enters the nitrogen storage tank through the left suction air valve and nitrogen gas production valve. This process is called left suction. Duration is 58 seconds.

After the end of the left suction process, the left adsorption tank and the right adsorption tank are connected through the upper and lower pressure equalization valve, so that the pressure of the left and right adsorption tank is balanced, this process is called pressure equalization, and the duration is 2 seconds.

After the end of pressure equalization, the compressed air enters the right adsorption tank through the right suction air valve, the oxygen molecules in the compressed air are adsorbed by carbon molecular sieve, and the enriched nitrogen enters the nitrogen storage tank through the right suction air valve and the nitrogen gas production valve. Duration is 58 seconds.

At the same time, the oxygen adsorbed by the carbon molecular sieve in the left adsorption tank is released back to the atmosphere through the pressure reduction of the left exhaust valve, which is called desorption.

On the contrary, when the left adsorption tank is adsorbed, the right adsorption tank is also desorbing. In order to completely discharge the oxygen released from the pressure reduction in the molecular sieve into the atmosphere, nitrogen is blown through a normally open reverse blow valve to purge the desorption tank and blow the oxygen in the tank out of the adsorption tank. This process is called blowback. It happens simultaneously with desorption. After the end of the right suction, enter the pressure balancing process, and then switch to the left suction process, and continue the cycle.

The work flow of the nitrogen machine is completed by the programmable controller controlling three pilot solenoid valves, and then the solenoid valves respectively control the opening and closing of eight pneumatic pipeline valves. Three pilot solenoid valves respectively control the state of left suction, pressure balancing and right discharge. The time flow of left suction, pressure balancing and right row has been stored in the programmable controller.

When the process is in the left suction state, the solenoid valve controlling the left suction is powered on, and the pilot gas is connected to the left suction intake valve, left suction production valve and right exhaust valve, so that these three valves are opened to complete the left suction process and the right adsorption tank desorption.

When the process is in the state of pressure balancing, the solenoid valve that controls pressure balancing is energized, and other valves are closed; The pilot gas is connected to the upper pressure balancing valve and the lower pressure balancing valve, so that these two valves open and complete the pressure balancing process.

When the process is in the right suction state, the solenoid valve that controls the right suction is energized, and the pilot gas is connected to the right suction intake valve, right suction production valve,

The left exhaust valve allows these three valves to open, completing the right suction process while the left adsorption tank desorbs.

In each process, except for the valve that should be opened, the other valves should be closed.



Fourth, equipment installation and use

Air separation nitrogen production equipment should be placed on a cement plane foundation.

The pipeline should be connected strictly in accordance with the process, as shown in Figure 2.

Five, equipment normal driving steps

1, open the cold and dry machine power supply, pre-cooling 3-5 minutes;

2, the air compressor is opened, and the compressed air is processed by the cold and dry machine and the filter into the air storage tank (the user can configure it).

Each pressure gauge indicates gradual rise;

3, when the pressure of the adsorption tank reaches 0.6MPa, open the power switch on the control cabinet, you can enter the normal

The working status of;

4, when the pressure of the nitrogen storage tank reaches 0.6MPa, and then slowly open the vent valve, then the flowmeter float can be observed

Rise, adjust the nitrogen flow rate to the user's required flow rate, nitrogen analyzer shows that after the purity reaches the user's required purity,

Close the vent valve, open the valve leading to the rear gas equipment, and the product nitrogen can be used.

Note: If there is an external gas storage tank, when the pressure of the gas storage tank is 0.6MPa:

The relationship between the rated flow and the actual flow under the normal state is: (simplified formula)

QN- Rated flow rate in normal state Qs-Flowmeter indicated flow rate PS- External nitrogen tank pressure (gauge pressure)

For example, QN = 10 Nm3/h PS = 0.6MPaX9.8

QS≈4Nm3/h is calculated, which is the value of the flowmeter when the nitrogen machine is working and the pressure of the gas storage tank is 0.6MPa.

When the rated nitrogen flow rate is 20 Nm3/h and the tank pressure is 0.6MPa, the flowmeter should indicate 8Nm3/h.



Six, equipment normal parking steps

1. Turn off the power switch of the nitrogen generator;

2, close the nitrogen gas supply valve;

3. Turn off the power switch of the cold and dry machine;

4. Turn off the power supply of air compressor;



Seven, equipment failure emergency shutdown steps

1. Turn off the power switch of the nitrogen generator;

2, close the flow meter downstream valve;

3. Turn off the power switch of air compressor and cold drying machine;

4, close the nitrogen gas supply valve;



Viii. Description of the normal operation status of the equipment

1, the power indicator light, left suction, voltage balancing, right suction indicator light cycle bright indicating the nitrogen production process;

2. When the left suction indicator light is on, the pressure of the left adsorption tank gradually rises to the highest from the equilibrium pressure during the pressure equalization, while the pressure of the right adsorption tank is increased

The equilibrium pressure gradually decreases to zero when the force is equalized.

3, when the pressure balancing indicator is on, the pressure of the left and right adsorption tank will gradually reach the balance of one liter and one drop;

4. When the right suction indicator light is on, the pressure of the right adsorption tank gradually rises to the highest from the equilibrium pressure during the pressure equalization, while the pressure of the left adsorption tank is increased

The equilibrium pressure gradually decreases to zero when the force is equalized.

5, nitrogen outlet pressure indicates normal gas pressure, the pressure will fluctuate slightly when used, but the change should not be too large;

6, the flow indicator of the flowmeter should be basically stable, the fluctuation should not be too large, and the value of the flowmeter should not be greater than the amount of the nitrogen production equipment

Fixed gas production;

7, the nitrogen analyzer value should not be less than the rated purity of the nitrogen production equipment, there may be a little fluctuation, but should not fluctuate too much.



9. Operation precautions

1. Adjust the nitrogen production valve after the flow meter according to the gas pressure and gas consumption, and do not adjust the flow rate at will to ensure the equipment's safety

Normal operation;

2. The opening of the nitrogen gas production valve should not be too large to ensure the best purity;

3, nitrogen analyzer flowmeter should be adjusted to 0.5L/h scale;

4, the valve adjusted by the debugging personnel should not be rotated at will, so as not to affect the purity;

5, do not arbitrarily move the electrical parts in the control cabinet, do not arbitrarily remove the pneumatic pipe valve;

6, the operator should regularly check the pressure gauge on the nitrogen machine, and make a daily record of the pressure changes in preparation for the equipment

Barrier analysis;

7. Regularly observe the outlet pressure, flowmeter indication and nitrogen purity, compare with the required value, and solve the problem in time;

8, according to the technical requirements of air compressor, cold dryer, filter maintenance and maintenance to ensure air quality (air source must

No oil). Air compressor, dry machine must be repaired at least once a year, according to the equipment maintenance, maintenance regulations easy to replace

Damaged parts and maintenance.

9, air separation nitrogen equipment in the process of work, carbon molecular sieve has a certain wear, should be inspected and filled once a year molecular sieve.

10. Complete the daily record form.