The principle of pressure control in a storage oil tank centers on maintaining a stable balance between the internal pressure of the tank and the external atmospheric pressure. This balance is critical to prevent structural damage and ensure the safe storage and handling of oil.
Passive Pressure Relief
- Uses vent devices like pressure-vacuum vents
- Opens automatically when internal pressure reaches pre-set limits
- Releases excess air or vapor during filling operations
- Draws in atmospheric air during emptying to prevent vacuum formation
- Relies on mechanical triggers without external power
Active Pressure Control
- Uses sensors to monitor pressure in real time
- Control units adjust pressure proactively
- Can activate mechanical valves to release vapor before critical levels
- May redirect excess vapor to recovery units instead of venting
- Introduces filtered air to maintain pressure balance
Vapor Pressure Management
- Accounts for vapor production from volatile oils
- Venting or recovery systems handle ongoing vapor production
- Non-volatile oils mainly experience pressure changes from volume adjustments
- Volatile oils require active monitoring and vapor handling
- Prevents pressure from building beyond safe limits
Pressure Fluctuation Causes
- Changes in the volume of stored oil
- Variations in temperature
- Vaporization of volatile components in oil
- Rapid filling or emptying operations
- External atmospheric pressure changes
In summary, the principle of pressure control in a storage oil tank revolves around proactive and reactive mechanisms that counteract pressure fluctuations. By combining passive vents for basic balance and active systems for precise control when needed, the tank maintains internal pressure within a safe range—protecting its structure, preserving oil quality, and ensuring safe operation.