Because of its design, a rotary airlock valve typically allows a small amount of conveying air to seep back into the airlock while it is sending bulk solid material to a conveying system. However, it’s important to deal with this leaked air properly in order to avoid problems for your equipment, like slowing down the flow of materials into the airlock or releasing dust into your facility.
Below, we’ll discuss three ways you can properly vent the air that comes from a rotary airlock valve leak so that you can avoid the resulting problems.
Option 1: Attach the Valve Directly to the Storage Vessel
Attaching the rotary airlock valve directly to the vessel that stores the material being moved to the conveyer system allows the valve to act as both an airlock and a metering device for the conveying line. Thus, the air that results from the rotary valve airlock leak goes straight into the storage vessel, moves through the material in storage, and then is vented from the top of the vessel. Often, the vessel has a bin vent filter that can exhaust the leaked air easily.
Option 2: Equip the Valve with a Surge Hopper
Equipping the rotary airlock valve with a surge hopper that has a dedicated vent filter. When sized proportionally to the airlock, the vented surge hopper can be fed in three different methods: it can be fed by another rotary airlock located below a storage vessel, it can be flood-fed from a storage vessel, or it can act as the transition to a metered feedpoint.
Option 3: Collect the Leaked Air in a Central Dust Collection System
By utilizing this method, the leaked air is contained in a plant’s central dust collection system – along with any entrained particles from the rotary airlock valve’s vented surge hopper. In this scenario, the dust collection system fan provides a negative draw to make sure that the leaked air follows a trail through the surge hopper and its vent until it reaches the dust collection system.
Contact ProcessBarron for More Solutions
The above solutions aren’t the only options, and each one comes with its own benefits and risks. Before you attempt to handle a rotary airlock valve leak on your own, you may want to speak with one of our trained professionals and get our expert opinion on the situation. You can also ask us about our double dump valves, which are much more resilient and won’t have the same constant leakage issues as a rotary valve. Contact us for more information!