GPPC and GPRC Technology Targets Gas Plant Performance

Barry D. Payne & Associates Inc. offer Advanced Process Control strategies designed for multiple platforms, that deliver plant improvements with your current controls today!

On Target Solutions include Advanced Gas Processing Control technology that delivers performance comparable to, or better than complex multi-variable control packages.  This technology runs in your DCS, or your PLC, or can be scaled down to a Multi-Loop Controller, and requires no host or supervisory computer.  Ongoing maintenance costs are significantly less than multi-variable controllers, while the installed cost of BDP On Target Solutions is typically less than 25% of a multi-variable control software application.

In Cryogenic Demethanizers, the controls incorporate two major elements:

  • GPPC - Gas Processing Performance Control - with C1/C2 or C2/C3 Composition Control and Cold Separator temperature control for maximum liquids recovery - combining inputs from an Onstream Analyzer, DeC1 Pressure, Inlet Gas Flow, Expander Outlet Temperature, and Reboiler Duty calculations to yield stable, reliable composition control and recovery from upsets.

In a recent paper, the GPPC controller was compared to a multi-variable controller costing in excess of six figures.  Standard deviation of the liquid to volume ratio C1/C2 data for the two strategies differed by only 0.15%, even though the total cost of the BDP On Target Solution was less than $20,000.

  • GPRC - Gas Processing Rate Control - with the composition under control, this Capacity Controller manipulates Cryo Processing Pressures and Recompressor Speeds or Recycle valves.  It seeks whichever limit (Inlet/Residue Pressure or Treating/Cryo Flow) is currently in effect, while being constrained from lowering Tower Pressure below "Coldspin" or Recompressor limits (Surge, Low Suction Shutdown, or Rod Loading).  This results in minimum pressure at any rate, normally maximizing recovery.  If fuel costs outweigh Ethane values, the order can be reversed, minimizing Recompressor horsepower at any throughput.

The GPRC controller has been utilized to balance parallel Cryo Plants with shared or split recompression, without wasting horsepower on "back-pressure" valves or other means.

Gas Processing Performance Strategies
Scalable CryoPlant Control Solutions for Your Current Automation Platform

Barry D. Payne & Associates, Inc.
P.O. Box 1829 (77497-1829)
10707 Corporate Dr., Suite 222
Stafford, TX 77477

Phone: 281-240-4488
Fax: 281-240-3913
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