VPSA oxygen production system start-up and shutdown operation steps

VPSA oxygen production equipment uses electricity as power and air as raw material. It uses the characteristics of lithium molecular sieve pressure swing adsorption to achieve the separation of oxygen and nitrogen in the air under the switching of the adsorption tower, and continuously produces the required finished oxygen.

VPSA is the abbreviation of vacuum pressure swing adsorption. This type of oxygen production system belongs to medium and large industrial systems and can provide oxygen with a purity of about 93% for use.

It is precisely because of the medium and large industrial systems that we should focus on the relevant management of safe production. For example, in the start-up and shutdown operations of the equipment, we should strictly follow the relevant operating steps to ensure the safety and specifications of the production process.

Preparations before starting the VPSA oxygen production system

1. Confirm that the blower bypass valve and vacuum pump bypass valve are open;

2. Turn the blower and vacuum pump to check the oil level of the main and auxiliary oil tanks of the pump;

3. Start the cooling water pump, open the air heat exchanger inlet and outlet valves, open the blower and vacuum pump cooling water inlet and outlet valves, open the sealing water tank inlet valve to add water, and confirm that the blower and vacuum pump drain valves are closed;

4. Start the instrument gas circuit and keep the gas supply force >0.6Mpa;

5. Open the oxygen vent valve;

6. Start the cabinet power supply.

Starting process of VPSA oxygen production system

1. Adjust the sealing water tank outlet valve. After the first adjustment, this step can be omitted;

2. Start the blower and vacuum pump and wait for stable operation;

3. Start the PLC. 4. Adjust various equipment parameters

a. Control the adsorber pressure through the air intake bypass valve to make its maximum pressure <45kpa, and the blower exhaust pressure <50kpa;

b. Control the vacuum degree through the vacuum bypass valve to make its pressure not less than -55kpa, and the vacuum degree of the vacuum pump port not less than -60kpa;

c. Adjust the oxygen vent valve and gradually close it to make the oxygen purity reach 93-95%;

d. Start the oxygen compressor according to the oxygen compressor operating procedures and close the oxygen vent valve.

VPSA oxygen system shutdown process

1. Shut down the PLC;

2. Shut down the blower and turn off the cooling water;

3. Turn off the vacuum pump sealing water, and shut down the vacuum pump after running it at no load for 5-10 minutes; in case of long-term shutdown, shut down the cooling water after running it at no load for 20 minutes, and when the ambient temperature reaches or is less than 0℃, open the pump drain valve to drain the cooling water inside the pump;

4. Disconnect the power supply of the starter cabinet;

5. Turn off the instrument air source;

6. Stop the oxygen compressor according to the oxygen compressor operating procedures.