Natural Gas Processing

15.25. Criteria for utility flow diagrams

The UFDs shall be prepared as separate drawing titled as Utilities Distribution Flow Diagram. The distribution of utilities for plant operation shall be shown on the drawing. The utilities for plant operation are generally classified as follows where applicable:

• several grades of steam;

• several grades of condensate;

• boiler feed water;

• cooling water and sea water;

• raw (fresh) water;

• plant and potable water;

• fuel oil and fuel gas;

• instrument and plant air;

• nitrogen;

• inert gas;

• seal oil/flushing oil;

• closed circuit hot oil system;

• flare and blow-down;

• chemical system such as caustic and ammonia.

The above utilities are classified into several groups and shown on diagram(s) in accordance with ...