Why ESP Original?

 

ESP Original is a powerful steady-state electrolyte process simulator with a dated User Interface (UI). ESP has addressed simulated aqueous chemical processes for a wide range of markets.

 

Designed originally in the early 1990s and funded by an OLI consortium of six clients, ESP (Electrolyte Simulation Program) has unique and fast convergence capabilities, critical for electrolyte processing. ESP became the fullest expression of OLI electrolyte thermodynamics, and contains flowsheet capabilities that include reaction kinetics and mass transfer in columns as well as more usual flowsheet units. 

 

Unit Operations

 

Unit operations include neutralizers, absorbers, strippers, extractors, reactors, incinerators, crystallizers, compressors, exchangers, dehydrators and saturators, as well as standard split, separate, mix and component split. Specialized operations (requiring client data for parameters for tuning) include membrane and electrodialysis.

 

Flowsheeting and control

 

Process flowsheeting with multiple recycles and control loops are allowed in ESP. Feedforward and feedback controllers and Manipulate blocks help to achieve process specifications

Hydrocarbons in ESP

 

Although this is an electrolyte process simulator, hydrocarbons are effectively modeled. Both ESP's AQ and Mixed Solvent Electrolyte (MSE) models accept pseudocomponents and hydrocarbon components as part of process input. In the AQ model, hydrocarbons are modeled using the SRK equation of state for both the gas phase and the hydrocarbon-rich nonaqueous liquid phase. In the MSE model, the SRK equation is used for the gas phase whereas both the aqueous and the hydrocarbon-rich liquid phases are modeled using the MSE activity coefficient model.

 

Sensitivities

 

The Sensitivity Block in ESP allows clients to determine the sensitivity of output results to changes in Block Parameters and physical constants.

 

User Interface (UI)

 

The UI in ESP Original has been problematic because of its age. Well designed and easy to anticipate, the original UI proves problematic particular to new users who are accustomed to newer, more standardized input. In spite of this drawback, ESP Original continues to be used and even preferred for its calculation and speed. Judicious use of MS Excel for drawing the graphics and CSV file based output allow present clients to overcome the older interface. A move to OLI Flowsheet: ESP with a new UI will be welcomed by everyone!

 

Dynamic Simulation

 

The ESP Original work included an electrolyte dynamic flowsheet simulator, DynaChem. Also hampered by a similarly dated UI, DynaChem allows the study of dynamic response of a process. Clients use DynaChem to examine control strategy, potential upsets, scheduled waste streams, controller tuning, and startup/shutdown studies. Studies of pH and compositional control, batch treatment interactions, multistage startup and shutdown, controller tuning, multicascade and adaptive control are all possible. 

Evaluation of DynaChem and application screening for DynaChem are available upon request.