OLI warm lime softening simulation

Lime and MagOx Silicate reactions modeling 


Simulating lime softener operation is challenging with the current OLI database since lime softener reaction thermodynamics and MgO-Si surface complexation kinetics are not well understood. Also, the lime softener simulation model needs an empirical component to account for the effect of contaminants including oil and grease, organics, and any polymers that are added to improve the phase separation.


In this project, a thermodynamic and kinetic-based model was developed that included precipitation kinetics and surface complexation of lime softening. The model parameters will be refined based on individual plant lime softening operation data. This model will be very useful for understanding the influence of various process parameters on lime softener performance and for optimizing the process conditions and chemical addition to improve the operation.

With a successful lime softener model, the following benefits can be achieved:

·       increased throughputs through lime softener, thus more recycled water means reduced waste water;

·       reduced chemical consumption, thus reducing indirect greenhouse gas (GHG) emissions; and

·       reduced lime softener operation upsets, which increases efficiency and reduces waste water.

This OLI simulation capability was developed in part by funding from COSIA in the Beyond Solubility project with OLI 


Subodh Peramanu, PhD

Process and Technology Advisor, CNRL 

Simulation and modeling work contributed by
AJ Gerbino, PhD

Vice President Client Success, OLI