1. Check before system startup
Confirm that the compressed air pressure (0.5-0.7MPa) and industrial steam pressure (0.4-0.6MPa) meet the requirements.
Check the condition of the filter element of the tank respirator, which needs to be replaced every six months due to aging.
2. Circulation and temperature control
Injection water needs to be kept warm and circulated at a temperature above 72 ℃, with a return water flow rate of>1.2m/s and 24-hour uninterrupted operation.
The high-temperature circulation system requires regular monitoring of temperature sensors to avoid overheating or underheating.
3. Cleaning and disinfection
Daily cleaning: Use 1% NaOH solution to circulate for 60 minutes, then rinse with injection water until neutral (pH test paper detection).
Sterilization operation: When the machine is shut down for more than one day per month, it is necessary to sterilize it with superheated water at 121 ℃ for 30 minutes and have it sampled and tested by QA. If the microorganisms exceed the standard, they need to be cleaned with 0.5% hydrogen peroxide solution and re sterilized.
Passivation treatment: After a new system or long-term shutdown, it is necessary to circulate a mixture of 8% nitric acid or hydrofluoric acid for passivation, and then rinse with injection water until the conductivity is consistent.
4. Maintenance and monitoring
The UV lamp tube of the TOC monitor needs to be replaced every six months, and the suction water pump head needs to be replaced every year.
Regularly calibrate conductivity sensors, pressure gauges, and other instruments to ensure accurate data.
5. Shutdown management
Shutdown for more than a week requires thorough sterilization (NaOH cleaning+121 ℃ superheated water) and full testing.
Turn off the UV light during shutdown to prevent equipment aging.
6. Material and Design
Priority should be given to using 316L stainless steel storage tanks, with a vertical design that makes it easier to empty. When the volume is too large, a horizontal design can be chosen.
The pipeline should be made of 316L material to avoid corrosion and microbial growth.
7. Safe operation
When it comes to tank maintenance, it is necessary to follow the requirements for confined space operations, install blind plates to isolate pipelines, and use explosion-proof tools.
Operators must be trained and qualified, and overpressure or illegal operations are strictly prohibited.
The above measures can ensure the compliance, microbial control, and equipment lifespan of injection water storage tanks.