Industrial Explosion Protection and Risk Assessment

I. Elements of an industrial explosion

combustible substances (dust, gas and smoke) mixed with oxygen in the air is ignited to produce an explosion. In the production process or closed storage container explosion, the pressure will rise rapidly within milliseconds, the resulting destructive force will put people and equipment in danger. Most equipment that handles, processes and stores materials is not designed to withstand the pressure generated by deflagration. Only specially designed to withstand the maximum pressure generated by the deflagration (Pmax) of the equipment can be spared, but the design pressure of such equipment is usually more than 75 psig (5.2 barg). So such equipment is incredibly expensive.

deflagration is a burning fireball to the speed of sound below the forward propagation of the phenomenon, is to be compared with the speed of sound above the burst phenomenon. Generally speaking, the protection of industrial equipment can be protected from the hazards of deflagration.

Second, dust explosion prevention and protection measures

Usually, the need to use several measures to eliminate the risk posed by deflagration. These measures can be applied to the technology can be divided into passive and active. Typical passive protection technology is mechanical, without the need for external energy. Explosion relief devices (called blast panels) are passive protection techniques. Active protection systems require one or more energy sources to function. Explosion suppression systems are active prevention technologies. Spark Detection and Elimination Systems are active prevention technologies that are used to detect and eliminate sources of ignition that could lead to a fire or explosion. Both active and passive guards require periodic inspection. Stainless steel blast panels provide affordable relief protection against dust explosions, but must be installed in a safe location that can accept the fireball generated by the relief.

Third, there are a variety of options for the assessment of explosion risk

These measures can be categorized as prevention and protection. The application of various measures need to be assessed separately , including the following.

1. to quantify the risk; identification of raw materials deflagration characteristics (may require experimental determination).

2. Consider whether to apply a combination of preventive and protective measures.

Explosive direct venting is favorable from an economic point of view, but the impact of the release must be fully assessed to determine the correct safety measures that can be applied:.

1. Can the fireball formed in a deflagration be released?

2. Can relief piping be installed to protect indoor equipment?

3. How can connected equipment be isolated to prevent the propagation of the explosion?

4. Can the equipment withstand the reaction force generated by the venting exhaust?

5. Can the building or equipment in the relief area withstand the blast pressure shock and the short-lived high temperatures of the fireball?

The answers to the above questions usually determine the type of protection that should be used, for example.

1. Measures to suppress explosion propagation without venting.

2. Preventive measures against fire + explosion hazards: (daily management and process management to limit the amount of combustible loads)

3. Anti-static management, especially for dust with low minimum ignition point (MIE).

4. Spark detection and elimination technology, i.e., management and control of spark-generating sources (e.g., grinding, milling).