Designing your dust collector hopper for mass flow
The flow properties of a free-flowing dry bulk material’s
fine fractions can be very different -- if not downright troublesome -- compared with those of the rest of the material. That’s why the fines collected in a dust collector hopper are subject to greater flow problems at discharge -- including slow flow, intermittent flow, and even a complete flow stoppage -- than solids discharging from storage vessel hoppers. This article discusses how to design your dust collector hopper to maintain steady mass-flow discharge of the collected fines and keep your process operating smoothly.
Designing an efficient, smoothly operating dust collection
system is no simple matter. Most of us concentrate
on the first part of this process: properly designing the dust collection system’s hoods and ducts to capture the dust and specifying a well-designed dust collector to remove the dust from the airflow. We think long and hard about how to maintain minimum airflows in the system’s ducts and branches, which filter element type and size is best, and how easy the filter elements will be to remove
and replace. But we tend to overlook the final part: designing the dust collector’s hopper to smoothly discharge the collected dust back to the process. Instead, we accept the collector manufacturer’s generic hopper design without question.