(112c) How Standpipes Really Work

Standpipes have traditionally been thought of as a device which allows solids to be transferred from a low pressure to a higher pressure. Standpipes can certainly do this, but their true function is not so limited. The actual purpose of a standpipe is to adjust the pressure drop across them so that the pressure drops around the circulation loop are in balance.

The four different types of standpipes and their operation will be reviewed. How each type of standpipe adjusts to balance the overall pressure drop in a circulation loop will be explained. Examples of standpipes adjusting to various operating conditions and solids flow rates will also be presented and described in detail.