# Mass Balances in Evaporative Crystallization

Requires a Wolfram Notebook System

Interact on desktop, mobile and cloud with the free Wolfram CDF Player or other Wolfram Language products.

Requires a Wolfram Notebook System

Edit on desktop, mobile and cloud with any Wolfram Language product.

In this Demonstration, you can perform mass balances on an evaporative crystallization process. Use the sliders to select the correct solution for the variables shown in green, then check the "solution" box to verify your answers. Click the "new problem" button for a new set of conditions.

Contributed by: Rachael L. Baumann and Neil Hendren (November 2018)

Additional contributions by: John L. Falconer

(University of Colorado Boulder, Department of Chemical and Biological Engineering)

Open content licensed under CC BY-NC-SA

## Details

Overall material balances

= mass flow rate of fresh feed (kg/h)

= mass flow rate of water exiting evaporator (kg/h)

= mass flow rate of solid KCl crystals exiting the crystallizer and filter (kg/h)

= mass flow rate of slurry exiting the crystallizer and filter (kg/h)

= mass fraction of KCl in fresh feed

= mass fraction of water in fresh feed

Material balance around crystallizer and filter

= mass flow rate of solution exiting evaporator (kg/h)

= mass flow rate of recycle (kg/h)

= mass fraction of KCl in stream exiting evaporator

= mass fraction of KCl in solution exiting crystallizer and filter

= mass fraction of water in solution exiting crystallizer and filter (this is equivalent to as the exit stream from the crystallizer is split)

= mass fraction of KCl in recycle stream

Material balances around mixing point

= mass flow rate entering evaporator (kg/h)

= mass fraction of KCl in stream entering evaporator

Material balance around evaporator

Dependence of solubility on temperature

= solubility of KCl in 100 kg

= evaporator operating temperature (°C)

= solubility of KCl in 100 kg

= crystallizer and filter operating temperature (°C)

Note that and , where is the stream.

Recovery rate

View the screencast video at [1] for more practice with material balances on a crystallizer.

Reference

[1] University of Colorado. *Crystallizer Material Balance with Recycle* [Video]. (Oct 29, 2013) www.youtube.com/watch?v=Dnfgc4_OFhI.

## Snapshots

## Permanent Citation