Explosion isolation is essential for comprehensive explosion protection. Without isolation, an explosion safety concept is not only incomplete, but is also a waste of money for operators as:
In almost every production facility, individual plant components are interconnected by means of pipelines. The purpose of explosion isolation is to seal these pipelines in the event of an explosion to prevent the propagation of pressure and flames, thereby protecting the adjacent plant components. Precompression and flame jet ignition increase the severity of the explosion in the connected vessels. This leads to secondary explosions that can cause even more catastrophic damage.
Isolation systems prevent an explosion from propagating, thereby reducing the effects of the explosion to a minimum. Adjacent system components are optimally protected.
A distinction is made between active and passive isolation systems:
Active systems use sensors or detectors to detect an explosion as it occurs by registering the rising pressure or flames as they form and activate the associated isolation device, e.g. a quench valve.
Due to their structural design, passive isolation systems react purely mechanically to a propagation or loss of pressure. The latter also applies to explosion isolation flap valve. They are kept open during normal mode by means of the currents present in the pipeline. In the event of an explosion, the valve closes due to the propagating pressure front, effectively preventing the further propagation of pressure and flames.