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Industry Applications, Oil & Gas
Mimic Dynamic Simulation for LNG Plants
By Zach Sample
Product: Mimic Simulation

The Mimic dynamic simulation application package for LNG plants provides a high performance solution for operator training and control system optimization.

LNG Liquefaction Plant (Source: Center for Liquefied Natural Gas)

The virtual LNG plant package provides the complete environment for control system optimization and is an effective tool for teaching process and control engineers the use and design of process controls in LNG plants.

Mimic Dynamic Simulation allows LNG Plant operations managers to:

  • Train operators on infrequent and dangerous process occurrences
  • Properly prepare an inexperienced operator workforce and create a smooth knowledge transfer process
  • Practice smooth operation and startup of liquefaction units
  • Test control system enhancements
  • Increase overall plant safety

This package uses Mimic Advanced Modeling Objects for dynamic, real-time, first principles modeling. The Mimic Advanced Modeling Objects are part of the Mimic Advanced Modeling Objects License that adds sophisticated modeling objects into the Mimic Simulation Studio modeling palette. These Objects can be used on Mimic systems for application software testing or operator training. The Mimic Advanced Modeling Objects License provides:

  • Medium to High Fidelity Simulation Performance
  • Rigorous First Principles process modeling using proven dynamic, real-time modeling methods
  • Modeling objects based on Unit Operations
  • Block to block communications of all parameters with one connection using Mimic Streams
  • Easy handling of individual stream component physical properties using Mimic Component Sets
  • Mimic OTM Process Snapshot support
  • Mimic OPC Server Access to all model parameters
  • Mimic OPC Bridge Communication with external Control Systems

In Mimic Simulation Studio, process models using these objects can be integrated with any other models or Mimic dynamic modeling blocks. All modeling objects in Mimic are IEC1131 function blocks. Models can be built off-line and then viewed executing on-line with real-time values from the Mimic Simulation engine. The process of going from off-line model building to on-line model tuning is fast and intuitive.

LNG Plant Dynamic Simulation

Mimic Dynamic Simulation for LNG plants provides accurate, real-time I/O updates to the off-line control system. The simulation consists of a collection of real-time, dynamic, first principles unit operation models configured to respond closely to the actual operations of the user’s facility. The scope of the simulation can be easily configured to meet the user’s and plant design’s needs.

LNG Plant Simulation Model as shown in Mimic Explorer

While there are a variety of LNG processes, in general a complete solution for a LNG facility will include a dynamic simulation for the following process areas:

  • CO2 Removal
  • Dehydration
  • Fractionation
  • Liquefaction
  • Storage

The most complex of these operations being natural gas liquefaction due to the involved heat exchange operations taking place between the natural gas and the refrigerant in and around the cold box.

Natural Gas Liquefaction

The pre-cooler and cold box are rigorously modeled using stacked Mimic Vessel VLE objects for each bundle. Models include the following functionality:

  • Dynamic, real-time mass and energy balances
  • Vapor-liquid equilibrium calculations performed at each pass of the model
  • Multiple two-phase outlet flows
  • Configurable activities and enthalpy correction factors to account for mixture non-idealities
APCI DMR Process Cold Box Model in Mimic Simulation Studio

In addition to the use of Mimic Vessel VLE objects to serve as flash drums, these models are supplemented with a dynamic, real-time pressure-flow network along with appropriate energy balances for each Mimic Compressor and Dynamic Heat Exchanger object.

Instructor Station Environment

The Mimic Component Studio instructor station graphic allows full control of the dynamic LNG Plant simulation with a dynamic Block Flow Diagram view of the major plant units and easy-to-use instructor controls. The following instructor controls are included:

  • LNG plant operating conditions including feed temperature, makeup composition, plant water conditions, and many other boundary condition controls
  • Individual pump and valve failure switches for ad-hoc instructor driven scenarios
  • Process Snapshot controls for full steady-state, cold start-up, and other critical LNG plant conditions
  • Operator training session scenarios with dynamic representation of current session student scores
LNG Plant Instructor Station graphic in Mimic Component Studio

Mimic Dynamic Simulation Application Packages

Mimic Dynamic Simulation Application Packages provide an excellent return on investment for plants training and operation budgets. Unlike other dynamic simulation technologies, they are:

  • Built for Operator Training and Control System Optimization. Because the dynamic simulation is built using Mimic Simulation Software, it fully supports operator training and configuration testing with any process control system environment. Mimic Simulated IO Drivers are non-intrusive and high performance, allowing IO simulation of any open process control system.
  • Easy to Customize and Modify. Mimic Operator Training Packages use Mimic Simulation Software Advanced Modeling Objects to deliver high-fidelity, dynamic process models. There is no hidden configuration in the solution. The user can easily modify the model to make it reflect the design of their plant design. The user can also add training scenarios and process snapshots as needed without limit.
  • Able to Work with Any Process Control System. Mimic models work directly with Mimic base level models and the Mimic Simulated IO System. This allows easy-to-maintain, accurate simulation of IO and control modules and provides real-time updates to the off-line control system.
  • Flexible, Powerful and Dynamic. The package is based upon Mimic Simulation Software; it is scalable from very small simulations to very large ones in the same software license. Mimic's multi-threaded simulation engine allows the fastest real-time performance of any simulation offering while still delivering accurate, dynamic simulations for a realistic operator experience at the control system operator station.
  • Scalable to Cloud Base Architecture. MYNAH Technologies is the industry leader in delivering cloud based dynamic simulation systems based upon VMware Virtualization Technology. MYNAH's Virtual Dynamic Simulators offer breakthrough flexibility and performance unavailable in legacy simulation architectures.
MYNAH's Virtual Dynamic Simulator brings the benefits of Cloud Based Computing to operator training systems.

The Virtual LNG Plant is an excellent platform for operators of liquefied natural gas production facilities to optimize their automation platform and address their operator training needs. Mimic Simulation Software is an enabling technology that addresses the needs of the energy industry process operators (see the Business Case for the Virtual Plant).

Ordering Information:

For a quotation or more information on Mimic Dynamic Simulation for LNG plants, contact MYNAH Technologies at +1.636.728.2000 or