Technical paper
Steady-State Simulators Are Developing A Dynamic Personality
Process simulators have been used for years to design and model actual operation of all types of different plant processes. The majority of process simulators provide a "steady-state" picture of plant operations and do not account for changes in inlet or ambient conditions. Steady state simulators are very useful when first designing a plant under a certain set of conditions, or when developing a baseline for plant operation. These simulators are also much more affordable than the dynamic simulators that are available in today's market. Unfortunately, plant operating conditions very seldom match design conditions and it is difficult for the Operator to discern what effect the changing conditions have on his process without performing numerous simulations using trial and error and manual manipulation. Even then, these results are often times suspect. Crosstex Energy Services, L.P. and Bryan Research and Engineering, LLC undertook a project to model one of the Crosstex gas processing facilities using the ProMax simulation software. Using the program's capabilities to rate the performance of various plant equipment, as it executes the simulation, and by utilizing available parametric study features that allow numerous runs to be made consecutively, without interruption, the ProMax simulator was able to provide a series of "snapshots" that provided a realistic and accurate prediction of how the plant will respond to changes in conditions. While this is still a prediction of steady state operation, the simulator has approached the dynamic threshold and only lacks the time derivative to cross over into that next dimension. This paper will show the steps that were taken to reach this point, the benefits it provided and how it might be used at other plant locations.
Process simulators have been used for years to design and model actual operation of all types of different plant processes. The majority of process simulators provide a “steady-state” picture of plant operations and do not account for changes in inlet or ambient conditions. Steady state simulators are very useful when first designing a plant under a certain set of conditions, or when developing a baseline for plant operation. These simulators are also much more affordable than the dynamic simulators that are available in today’s market. Unfortunately, plant operating conditions very seldom match design conditions and it is difficult for the Operator to discern what effect the changing conditions have on his process without performing numerous simulations using trial and error and manual manipulation. Even then, these results are often times suspect. Crosstex Energy Services, L.P. and Bryan Research and Engineering, LLC undertook a project to model one of the Crosstex gas processing facilities using the ProMax simulation software. Using the program’s capabilities to rate the performance of various plant equipment, as it executes the simulation, and by utilizing available parametric study features that allow numerous runs to be made consecutively, without interruption, the ProMax simulator was able to provide a series of “snapshots” that provided a realistic and accurate prediction of how the plant will respond to changes in conditions. While this is still a prediction of steady state operation, the simulator has approached the dynamic threshold and only lacks the time derivative to cross over into that next dimension. This paper will show the steps that were taken to reach this point, the benefits it provided and how it might be used at other plant locations.