Mass and Partial Energy Balance

The process flow diagram attached shows a very simplified approach to the production of Potash from Sylvinite ore. Conduct a mass balance and a partial energy balance across this process using the data constraints and stream information outlined below. A molar balance is not required. Provide a concise report outlining your methodology, assumptions made and your mass balance table/spreadsheet. The report should be no more than 10 A4 pages including tabular output and handed in on Tuesday 9th October, 13:00 in ChE 124, as well as through webct.

An energy balance across the two dryers, the hot leach and the crystalliser is required. Discuss how heat integration might be applied. Brine is used to facilitate the separation of KCl from NaCl.

Brine is saturated sodium chloride solution. At ambient temperature it will dissolve neither KCl nor NaCl. At 90°C it will form a solution with the mass composition: 0.6% NaCl, 20%KCl, 79.4% brine. For the purpose of the mass balance treat the brine as a constant composition liquid. For the energy balance across the two fluidised bed dryers, treat it as H₂O, comment on the validity of this assumption.

Note that the percentage separations given in the table below are nominal and may be adjusted within reason to help achieve the product specification and yields.