Preventive Measures of Air Storage Tank Explosions

Air storage tanks are an essential part of compressed air systems, but improper design, quality issues, or operational errors can lead to severe safety accidents, such as explosions. These explosions not only threaten the safety of equipment and personnel but can also result in significant economic losses. Therefore, it is crucial to thoroughly analyze the causes of air storage tank explosions and establish effective preventive measures.

Causes of Air Storage Tank Explosions

The causes of air storage tank explosions are typically multifactorial, involving design flaws, improper material selection, poor manufacturing quality, improper operation, and failure of safety protection devices. Below are the primary causes:

1. Design and Manufacturing Defects

If structural integrity, material selection, and manufacturing processes are not carefully considered during the design phase, the tank may develop structural defects. For example, uneven wall thickness, porosity, cracks, or severe corrosion can compromise the tank's strength. These defects may lead to an explosion, even when the tank is operating under its rated pressure, as certain areas of the tank may lack sufficient strength.

2. Failure of Safety Devices

The pressure inside the air storage tank is regulated by pressure regulators and safety valves. If any of these devices fail, it can cause the pressure to become uncontrollable, potentially leading to an explosion. For instance, errors in the operation of pressure regulators, faults in the relief valve piping, malfunctioning safety valves, or inaccurate pressure gauge readings can cause a rapid increase in pressure, creating a dangerous situation.

3. High Temperature

Excessive internal temperature in the air storage tank is another significant cause of explosions. External factors such as exposure to sunlight or fires can raise the temperature of the gas inside the tank, causing the pressure to increase rapidly. When the temperature and pressure exceed the tank's structural limits, an explosion can occur.

4. Explosion Caused by Lubricating Oil

Mineral lubricating oils used in reciprocating piston compressors are flammable. If the gas temperature rises above the oil's flashpoint, the lubricating oil can undergo rapid oxidation, potentially causing an explosion. Additionally, carbon buildup from lubricating oil can form in the gas flow system. This carbon can spark due to mechanical impact, hard particle friction, or electrostatic discharge, further triggering an explosion.

5. Vibration-Induced Explosion in Exhaust Systems

The exhaust system of a compressor is often subject to damage from excessive temperature, improper piping installation, or vibrations. Excessive vibrational stress can cause pipes to loosen or crack, leading to gas leaks, or in severe cases, an explosion.

Preventive Measures for Air Storage Tank Explosions

To prevent air storage tank explosions, a comprehensive set of preventive measures must be implemented to ensure the safety, reliability, and long-term stability of the equipment.

1. Design and Manufacturing Optimization

Reasonable Design: During the design phase, materials should be appropriately chosen, and the structure should be optimized to ensure uniform strength across the tank. Issues like weak spots or uneven wall thickness should be avoided.
Use of Qualified Materials: High-strength materials that meet the required standards should be used, avoiding substandard materials.
Quality Control: Stringent quality control procedures must be followed during manufacturing to avoid defects like porosity, cracks, or other quality issues.

2. Safety Protection Devices Installation and Maintenance

Pressure Protection Devices: Install automatic pressure protection devices in the air storage tank to ensure timely shutdown or pressure relief in the event of overpressure, preventing explosions.
Regular Calibration of Regulators and Safety Valves: Pressure regulators and safety valves should be regularly calibrated and inspected to ensure reliable and flexible operation, particularly ensuring that safety valves activate at the set pressure.
Operator Training: Operators should undergo thorough training to familiarize themselves with safety procedures for air storage tanks. Regular safety drills should be conducted to ensure quick and correct responses in emergencies.

3. Temperature Control and Lubricating Oil Management

Control Gas Temperature: Regular checks of the compressor's cooling system should be conducted to ensure the water quality meets the required standards. Scale buildup on cooling pipes and cylinder walls should be cleaned, and the temperature difference of the cooling water should be controlled.
Lubricating Oil Selection: Use lubricating oils suitable for the equipment as specified in the technical documentation and control the amount of oil used, avoiding excessive or insufficient lubrication.
Prevent Carbon Buildup: Maintain the cleanliness of the exhaust system to prevent the accumulation of carbon from lubricating oils. Carbon deposits should be regularly cleaned to prevent explosions caused by thick deposits.

4. Pipe Design and Installation

Optimize Pipe Design: When designing piping systems, minimize the use of elbows, valves, and reducers, or increase the radius of bends to reduce vibrational forces on the pipes. Reducing pipe vibration helps avoid rupture and leakage.
Standardized Installation: Equipment installation must follow design requirements strictly to ensure secure connections between pipes, air storage tanks, and other components, preventing issues arising from poor installation.
Vibration Control: For pipes already experiencing vibrations, buffers or supports should be added at critical points to reduce the impact of vibrations on the system. Special attention should be given to pipe vibrations between the air storage tank and compressor, and the tank's volume may be increased to reduce uneven pulsating pressure.

5. Maintenance and Inspection

Regular Inspections and Maintenance: Regular checks and maintenance should be conducted on the air storage tank and compressor. Any potential safety hazards should be promptly addressed. Inspections should include checking gas pressure, temperature, lubricating oil condition, carbon buildup, etc., to ensure optimal system performance.
Carbon and Oil Residue Cleaning: The air storage tank and exhaust system should be cleaned regularly to prevent excessive carbon buildup. Oil residues and carbon should be removed to keep the system clean and unobstructed.

Conclusion

The occurrence of air storage tank explosions is often the result of multiple contributing factors. Through proper design, strict manufacturing quality control, the installation of effective safety devices, adherence to correct operational procedures, and regular inspections and maintenance, the risk of such explosions can be significantly reduced. These preventive measures should be rigorously followed in practice to ensure the safe and stable operation of the compressor system, effectively protecting personnel, equipment, and the production environment from harm.