4.1.1 Lock hoppers
Although the concept of lock hoppers has been known for a very long time, and has been utilized in many other areas of industry, it has been slow in being adopted in pneumatic conveying. It is not only blow tanks that can benefit from their use, however. As the lock hopper enables the feeder to operate without a pressure drop existing across it, conventional rotary valves and conventional screw feeders can also be used for the