Improving Plant Production Capacity
Changing market conditions and energy costs have been key drivers for many companies to focus on improving production
capacity of chemical plants.  Existing plants always achieve maximum production capacity up to limitations of certain key
pieces of equipment, or sometimes several pieces of equipment.  The production capacity limitation may be caused by a
variety of restrictions, including a process pressure or temperature limitation, a maximum rotating equipment speed, a rotating
equipment driver power limit, maximum flows through equipment of existing size with corresponding high fluid pressure losses,
reduced process conversions or yields at maximized plant rates, and, high heat fluxes and resulting impacts on furnace
equipment and boilers, causing excessive tube metallurgy temperatures or departure from nucleate boiling in associated
boilers.  There are also a variety of other plant production capacity limitations too numerous to cover in this brief process
technology article.

When owners of exiting chemical plants decide to increase plant production a “Base Case” plant performance study should be
completed.  This Base Case plant study should be developed at a time frame when the plant is operating at or near the
maximum production rate possible, with all of the key equipment causing the production capacity limitation carefully
documented.  Plant site operating personnel and the process engineering staff should develop a complete listing of all
operating plant process information to be recorded prior to the study, fully representing the Base Case plant performance.  
This process information should include all feedstock compositions, flows, temperatures and pressures, measured plant
product flows and flowing conditions, all key equipment thermocouple and pressure readings, all stream analyses, and rotating
equipment speeds, from process computer hardware, as well as key local field instruments where on-line process computer
information may not exist.  Since the process information changes continuously, it is best to gather this data over at least a
shift, and preferably for about 24 hours and use logical segments of the data, or averages of the data in the plant
performance analysis, representing the Base Case operation and plant performance.

Plant personnel fully experienced with the facility, and/or others having complete expertise and knowledge in performing
process simulation and related process performance calculations should develop plant models and performance analyses from
the Base Case process information, to accurately represent the detailed plant equipment performance.