Most dust collectors are equipped with a motor-driven rotary airlock valve that empties contents from the hoppers. Rotary valves have been used for many years and do obtain some advantages. However, cleaning rotary valves is difficult and time consuming. These valves run continuously, regardless if dust is present, which leads to wasted electricity. In addition, the valves can wear out rapidly, resulting in costly repairs and replacements. A highly cost-effective alternative is Aerodyne’s Vacu-Valve® Trickle Valve System. The Vacu-Valve relies on the negative pressure of the material handling system to hold the duckbill sleeve closed. As the dust or material builds up, the sleeve is forced open, allowing the contents to discharge. Once emptied, the negative pressure then immediately closes the duckbill again. This trickle valve system requires no lubrication, power, or controls. Materials that would normally jam or wear out a rotary airlock valve, the Vacu-Valve handles with ease. There is a variety of duckbill sleeve options designed for specific applications; and the Vacu-Valve is available in an open or closed design, to further accommodate the particular application.