GPS-X Technical Reference

GPS-X Objects 28
TYPES OF OBJECTS
Common Properties
Before describing each object that appears on the GPS-X Process Table, an outline of
the properties common to some objects is presented. The objects in the Process Table
can be described as either having volume or not. There are some deviations from this
general rule, but they can be ignored for now. For example, the control splitter object
does not have any volume (called “zero volume”), while the equalization basin does have
volume. The zero volume objects do not have any dilution or residence time while the
objects with volume do.
Objects with volume have one or more influent connection points and one or more
effluent connection points. For example, the settler objects have one influent connection
point plus three effluent connection points, while the PLUG FLOW-TANK(2) object
has three influent connection points and two effluent connection points. The effluent
connection point(s) will have an overflow connection plus one or more pump
connections. The overflow is located at the upper right hand corner of the object (as
oriented in the Process Table), while any additional output connections are located on
the right hand side or bottom of the object. The additional output connections (either
called pump or underflow) simulate a constant or variable flow pump so that a flow rate
can be specified (up to the maximum pump capacity).
The volume of fluid in the tank depends on the net influent - effluent flow. If this is a
negative value, then the volume of the tank will decrease until it reaches zero. At this
point the effluent will equal the influent, regardless of the pump flow set. If the net
influent-effluent flow is positive, the tank volume will increase until the maximum
(specified by the user). At this point, the tank begins to overflow, so that the effluent flow
(sum of the overflow and pump flows) will be equal to the influent flow. The effluent
flow over and above the effluent pumped flow rates will leave through the overflow
connection point. If the net influent-effluent flow is zero, then the volume will not
change.
GPS-X Technical Reference