Flame, Dust and Pressure Control
4 safety functions of the IQR System™
• Flame Arresting – No flame escapes provides a safe operating environment for all the personnel and eliminates the secondary ignition possibility including following external explosion to the protected equipment.
• Dust Retention – Helps to retain process product to remove the potentially toxic product possibility entering the environment.
• Pressure Retention – Helps to absorbs explosion pressure peak and protects surrounding environment and personnel from pressure blast.
• Temperature Control – Helps to absorbs fireball with minor temperature rise in the surrounding environment.
HOW THE IQR SYSTEM™ WORKS
The quenching module helps to retain the hot gases and flames of a deflagration which includes the unburned and burning dust passing across the open explosion vent. The three-dimensional mesh arrangement behaves as a heat sink interrupting the explosion in mid-stream including pressure absorption wave and dust that normally gets ejected by a vented explosion.
While the dust explosion flame ball temperature can easily reach 932°F /500°C, the IQR quenching module naturally remains under 212°F /100°C followed by quick cool down as it has large surface area. The result is a negligible temperature changes in the environment that surround the IQR System.
With the dust retention, flame quenching and pressure control process and temperature given by IQR system, this safety device can be used indoors whenever the vented explosion impact needs to be avoided.
APPLICATION OF THE IQR SYSTEM™
The IQR System is primarily known for explosion venting using Codes and Standards such as NFPA 654, NFPA 68 and the European Atex Directive. The IQR System provides solution for the process equipment protection installed indoors where one or many conditions mentioned below exists:
o Venting to outside need ducting that is longer. Vent ducting that surpasses 6m/20ft in length is not recommendable — ducts up to 3m/10ft in length have the minimal impact on the pressure developed inside the protected process equipment.
o No space to install venting is possible. This can happen where equipment is closely packed having no space for straight and short ducting.
o No access is possible to outside for vent ducting. This can happen where equipment is installed in basement where outside wall is absent.
o Release of fireball outdoor is unacceptable; a fireball could be ejected up to 30m/100ft and have 10 times the process equipment volume that is protected.
o Release of dust (both unburned and burned) outside is unacceptable.
o Explosion pressure pulse release is unacceptable; neighboring building structures could be damaged by a pressure pulse which exceeds 2 or 3 psi across the large area for a short interval.
Majority of these application issues apply to outdoor process equipment. The IQR System can be applied to outside process equipment where safety measures should be taken to avoid snow buildup, water and ice in the quenching module.
Information required to be specified in the IQR System™
The IQR System™ is primarily a device used for explosion venting. The below information is essential to select and specify the proper IQR unit for your application.
o Process Dust (Pmax and Kst)
o Protection pressure for process equipment (Pred)
o Process Equipment Description (Volume(s));
o Normal operating pressure and temperature
Installation, Inspection and Maintenance
The IQR System is simply mounted by a bolted flange connection at the inlet, similar to an explosion vent mounting process. Installation can be in any suitable location.
If you are thinking of larger sized IQR devices or where mounted to weak equipment, extra bracing can be needed by linking to the eyebolts supplied with each individual IQR unit. The IQR system is constantly delivered with a monitor circuit and an integral Burst Alert® sensor that can generate an alarm signal when the device gets activated. Codes need that this alarm signal to shut down the process of stopping the dust feed and air that acts as the fuel for any explosion.
Annual inspection of the IQR system is always suggested to a factory trained personnel. As IQR is normally a passive safety device, like an explosion vent, regular inspection can ensure best safety.
Factory trained personnel are offered for assisting with commissioning and annual inspection. Future changes to standards and codes need both active and passive safety systems that require periodic inspection. The IQR system has no need for maintenance requirements. Commissioning and annual inspections will automatically recognize any planned maintenance necessities for each individual application.
Once the system gets activated, there is negligible external cleanup when compared to an open vented dust explosion. The IQR System can naturally be restored after activation for quick restart.