In three parts, this article by Rembe GmbH will give comprehensive information about the basics of explosion safety and the available protective systems for this purpose.
Conventional venting through the use of explosion vents
If a plant is situated outside buildings or if parts of a plant are next to an outer wall, one frequent safety precaution is to install explosion vents. Such precautions are usually applied, for instance, to stationary silos, filters, and elevators that are situated outside of buildings. If an explosion occurs, the explosion vent protects the system by opening. This reduces any overpressure within the vessel and the explosion is released to the outside. As virtually no processes are the same, there are numerous types of explosion vents, which differ in shape and material, as well as their resistance to temperature, pressure, and vacuum. Even processes with considerable hygiene requirements can be equipped with explosion vents today. The explosion vent EGV HYP, made by a German company, was highly successful in passing the European Hygienic Engineering and Design Group cleanability test. The test involves ensuring the in-place cleanability of plant components where this is a practical requirement for the manufacturing of hygienic products.
If a plant is situated within a building, however, explosion vents are not suitable for pressure relief purposes, as the safety area around them is inadequate to relieve the emerging dust and flames. Such an arrangement would pose an enormous safety risk to humans and machinery. This problem is often solved through the use of vent ducts, which channel the spread of an explosion to the outside. The disadvantage, however, is that it prevents any process-optimised plant design and is usually very expensive. This is because the longer the distance between an explosion and its source, the higher the pressure that the vent duct and the plant need to withstand, resulting in higher (production) costs for the vent duct.
Flameless venting, on the other hand, is an option that is both economical and effective. Different manufacturers use different technologies in flameless venting.
For example, the special mesh filter that is used in a Q-Box or Q-Rohr efficiently cools down any flames, preventing both flames and pressure from emerging and ensuring particulate retention. The typical increase in pressure and noise that accompanies an explosion within a building is reduced to an almost imperceptible minimum, thus protecting both humans and machinery. In addition to the special stainless steel mesh filter, the Q-Rohr and Q-Box each have an explosion vent with an integrated signalling system that alerts the process control system when the explosion vent has opened.
REMBE provides customers in all industries with safety systems for their plants and equipment.
Read the article online at: https://www.worldcement.com/special-reports/28122018/everything-you-need-to-know-about-explosion-safety/