Intermittent Blowdown (IBD)

Many boilers are equipped with a lower drum which is commonly referred to as the “mud drum.” This drum is installed to allow circulation of water between itself and the steam drum. One side of the two drums is connected with risers, while the other side is connected with downcomers. This creates a circulatory path between the two drums.

This bank of tubing between the two drums is sometimes referred to as the “generator section.” During normal operation, solids such as sludge tend to accumulate in the lower drum. To get rid of these solids, periodically a small amount of water is sewered from the mud drum. This type of water discharge is referred to as the Intermittent Blowdown. Usually the IBD valves are opened for a few seconds during every shift.