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06.08.2020, Remscheid, Germany
Meike Schulz, RHEWUM GmbH
In the port of the Lebanese capital Beirut there was a huge explosion which caused over 100 deaths and countless injuries. The exact cause of the accident is still unknown. It is suspected that a fire ignited the ammonium nitrate stored in the port. On this occasion we would like to take up this topic and inform you about possible dangers in the field of ammonium nitrate screening. Screen your ammonium nitrate safely and without risk by using RHEWUM screening technology.
Ammonium nitrate is considered to be oxidizing but cannot ignite itself - unless large quantities are close together. Then it starts to work and heats up. The ammonium nitrate catches fire. This releases oxygen and the fire spreads. In fertilizers, it may only be used in mixtures due to its latent danger. But what does this mean for screening?
Possible risks that could arise during a screening process of ammonium nitrate are, for example, high dust generation, which can lead to dust explosions and damage to health. In conformity with the ATEX directives RHEWUM screening machines are equipped with a dust-tight housing with connection to a dust extraction system to avoid high dust concentrations. A further risk is the required vibration during screening. All moving parts of a screening machine (e.g. the excitation axles, springs or bouncing balls for cleaning the meshes) which come into contact with ammonium nitrate can potentially cause an effective force. This friction can cause heat, high pressure and high impact energies.
However, internally conducted case studies of our screening experts have shown that all moving parts in directly excited RHEWUM screening machines generate 23 times less impact energy than would be required for ignition. For RHEWUM screening machines with a linear motion the case study evaluations even showed 39 times less impact energy.
In order to screen ammonium nitrate safely open flanges/lids should be avoided, the control of the suction air/dedusting should be checked and regular cleaning and inspection of the equipment should be carried out to avoid possible "death zones" (e.g. corners where the product can get stuck). The RHEWUM screening machine models WA, WAU and WAF, which are preferred for ammonium nitrate, all have an installed program control unit which is used for automatic cleaning of the screen cloths by adjustable pulses. Also screen overloads at higher energies can cause risks which are not foreseeable.
Since the 1960s, we have implemented numerous solutions for explosion-proof screening of ammonium nitrate together with our customers. Find out now about an ATEX-compliant screening machine and let our screening experts advise you without obligation. Our know-how for your safety.
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