Aerodyne’s Vacu-Valve® Trickle Valve System is the most cost-effective way to manage dust discharged from bag filters or cyclones under negative pressure. The Vacu-Valve consists of an automatic non-powered valve and has a duckbill rubber sleeve which is held closed by the negative pressure. As material builds up, the sleeve is forced open and the material discharges from the hopper. The system’s negative pressure then closes the sleeve automatically. Wagner Quarries Company, a state-of-the-art limestone mining facility located in Sandusky, Ohio, was experiencing very costly problems with its rotary airlock valves. Due to the abrasive nature of limestone dust, the rotary airlock valve’s performance was short lived. In addition, the difficult access to the drive assemblies made repairs a challenge. The company decided to replace their expensive rotary airlocks with the much more cost-effective Vacu-Valve from Aerodyne. This trickle valve system improved overall process efficiency and saved an estimated $8,000 to $10,000 a year or more.