Design Parameters of Explosion-Propylene Oxide Storage Ventilation System?

Design Parameters of Explosion-proof Ventilation System for Propylene Oxide Storage Warehouse

propylene oxide is an important chemical raw material, which is widely used in polyurethane, epoxy resin, textile auxiliaries and other fields. Propylene oxide is flammable and explosive, and improper management during storage can easily lead to safety accidents. Therefore, in the design of propylene oxide storage warehouse, explosion-proof ventilation system is a vital part. This paper will analyze the key elements of the explosion-proof ventilation system of the propylene oxide storage warehouse in detail from the perspective of design parameters.

1. Explosion-Proof Ventilation System Design Objectives

Propylene oxide will form an explosive mixture in the air if it leaks or volatilizes during storage. When the explosion limit is reached, the ignition source such as open flame or electrostatic spark may cause an explosion accident. Therefore, the core goal of the explosion-proof ventilation system is to reduce the concentration of propylene oxide vapor in the warehouse below the lower explosion limit through effective ventilation. The ventilation system also needs to take into account multiple safety requirements such as explosion-proof, fire prevention and corrosion prevention.

2. ventilation design parameters

1. ventilation number method The calculation of ventilation volume is an important basis for the design of explosion-proof ventilation system. Generally, the air change rate method is a common method for calculating the ventilation volume. According to the Code for Fire Protection Design of Buildings and the Code for Safety of Hazardous Chemicals Warehouse, the ventilation rate of the propylene oxide storage warehouse shall not be less than 3 times per hour, and may be increased to more than 5 times per hour under special circumstances. The higher the ventilation rate, the better the ventilation effect, but the energy consumption also increases accordingly. Therefore, it is necessary to find a balance between safety and economy in the design.

2. leakage calculation method Another method of calculating ventilation is based on the leakage of propylene oxide. Assuming that the leakage of propylene oxide in the warehouse is Q (unit: kg/h), the ventilation rate should be at least 10 times of Q to ensure that the leaked propylene oxide vapor can be discharged in time. For example, if the leakage of propylene oxide is 0.5 kg/h, the ventilation rate should be at least 5 m³/s.

3. wind speed design parameters

In the propylene oxide storage warehouse, the design of wind speed should take into account the uniformity and safety. Too low wind speed will lead to the accumulation of propylene oxide vapor in the dead corner area, while too high wind speed may cause equipment vibration or dust flying, affecting safe production. Generally speaking, the wind speed of propylene oxide storage warehouse should be controlled between 0.5 and 1.0 m/s. The distribution of wind speed should be uniform to avoid too low or too high wind speed in local areas.

4. air outlet design parameters

The location and design of the air outlet directly affect the efficiency of the ventilation system. The exhaust outlet of the propylene oxide storage warehouse shall be set at the top of the warehouse, and the propylene oxide vapor shall be effectively discharged by using the principle of hot gas rising. The opening area of the air outlet shall meet the ventilation requirements, and the ratio of the area of the air outlet to the area of the warehouse shall not be less than 1:50. The air outlet should be far away from the air inlet to avoid short circuit of hot and cold air and affect the ventilation effect.

5. explosion-proof ventilation system other design parameters

1. Gas detection equipment Propylene oxide leak detector and combustible gas detector shall be installed in the propylene oxide storage warehouse. These devices can monitor the gas concentration in the warehouse in real time. When the concentration reaches the set value, the system will automatically start the exhaust fan or issue an alarm signal. The selection of gas detection equipment shall meet the explosion-proof requirements to ensure safe operation in explosive environments.

2. Type Selection of Explosion-proof Fan The core equipment of the explosion-proof ventilation system is the explosion-proof fan. When selecting a fan, it is necessary to consider factors such as air volume, air pressure, and power. The explosion-proof fan of the propylene oxide storage warehouse shall have a high explosion-proof grade, such as Ex d IIA T4 protection grade, and meet the requirements of relevant standards. The installation position of the fan should be far away from the fire source to avoid safety accidents caused by equipment failure.

3. Safety control parameters In order to ensure the safety of the explosion-proof ventilation system, it is necessary to set the safety interlock device in the system. For example, when the concentration of propylene oxide in the warehouse reaches a certain value, the system will automatically close the ventilation pipe to prevent the propylene oxide vapor in the air from flowing back to other areas. The air outlet shall be equipped with flame arrester and explosion-proof valve to prevent external fire from entering the warehouse through the air outlet.

6. operation and maintenance

The explosion-proof ventilation system of the propylene oxide storage warehouse needs regular inspection and maintenance. Including cleaning the dust in the ventilation pipe, checking the operation status of the fan, calibrating the gas detection equipment, etc. Through regular maintenance, to ensure that the system is always in the best working condition, to provide a reliable security for the storage of propylene oxide.

Conclusion

The design of an explosion-proof ventilation system for a propylene oxide storage warehouse is a complex and elaborate process that involves a comprehensive consideration of multiple design parameters. Through the reasonable design of key parameters such as ventilation, wind speed, exhaust outlet, and the selection of gas detection equipment and explosion-proof fan, the explosion risk of propylene oxide vapor can be effectively reduced to ensure the safety of the storage process. In the future, with the continuous development of the chemical industry, explosion-proof ventilation technology will continue to innovate to provide more efficient and safe solutions for the storage of hazardous chemicals such as propylene oxide.