Pipeline Control Optimization

Industry

Power

Business Issue

One of the immediate primary business objectives for a pipeline company is to increase its pipeline flow rate capacity in one of the major lines that transports heavy and light crude oil. The line consists of a total of 25 stations, which include intermediate, mainline, and delivery stations and runs over 1,000 km. The normal flow rate in the pipeline has been around 3,500 m3/hr.  The new flow rate in the pipeline is projected to be around 5,000 m3/hr.

Project Summary

The project involved conducting performance tests, reviewing the existing control strategy, and re-tuning pressure control loops.  In order to assess the health of the equipment and control loops, performance tests are conducted using Flowscanner and EnTech Toolkit software on both the control valve and the control loop.

Any field equipment that is identified as being “unhealthy” is repaired and calibrated.

The existing control strategy was also reviewed, which was a necessary step along with a process fluid simulation of the pipeline. The simulation was performed jointly with a consulting company specializing in pipeline simulation and using simulation software. The goal was to evaluate expected performance and behavior of each station’s control system under different tuning sets.

Finally onsite optimization tasks were performed, such as changing control configuration and implementing optimum pressure control loop tuning.

Scope Responsibility

Cornerstone Controls was responsible for the following areas:

  • Performance tests on pressure control valves and control loops to assess the health of equipment and control loops.
  • Provide training on pressure control valves and actuators to more than 30 maintenance personnel.
  • Review and improve pressure control strategy.
  • Dynamic performance tests at each of the 25 pipeline stations.
  • Optimum tuning of holding, suction, and discharge control loops at each station.
  • Project management to meet aggressive schedule and control cost.
  • Commissioning of pressure control system at each pipeline station.

Results

  • Project completed on schedule and 10% under budget.
  • Pipeline station control commissioning performed without affecting scheduled flow-rates.
  • Pipeline is now pumping between 4,500 and 5,000 m3/hr.
  • Station interaction has been significantly reduced due to more comprehensive loop tuning.
  • Significant energy savings were produced due to having optimum control valve movement and eliminated valve restrictions under steady state operation.