Question

Explain how each of the following statements might affect the layout of process equipment:

A specific pump requires a large NPSH.

The flow of liquid from an overhead condenser to the reflux drum is gravity driven.

Pumps and control valves should be located for easy access and maintenance.

Shell-and-tube exchanges may require periodic cleaning and tube bundle replacement.

Pipes located at ground level present a tripping hazard.

The prevailing wind is nearly always from the west.

Answer 1

(a) For a pump with a large NPSH, the vertical distance between the feed vessel and the pump inlet must be large in order to provide the static head required to avoid cavitating the pump. 

(b) Place the overhead condenser vertically above the reflux drum, the bottom shell outlet on the condenser should feed directly into the vertical drum. 

 

(c) Pumps and control valves should always be placed either at ground level (always for pumps) or near a platform (sometimes for control valves) to allow access for maintenance. 

(d) Arrange shell and tube exchangers so that no other equipment or structural steel impedes the removal of the bundle. 

(e) This is why we have pipe racks never have pipe runs on the ground. Always elevate pipes and place on rack. 

(f) Locate plant to the east of major communities.