1. Dr Saad Al-ShahraniChE 201: Introduction to Chemical Engineering  Separation operations are subject to the conservation of mass  Separation of components of a mixture are carried out to effect desired component recovery or product purity.  To determine the effectiveness of a separation operation, we need a measure of the degree of separation. 1.Steady state. 2.Continuous. 3.No chemical reactions occur.  If the separation process is: COMPONENT RECOVERIES AND PRODUCT PURITIES

2. Dr Saad Al-ShahraniChE 201: Introduction to Chemical Engineering  Then for each component, i, in a mixture of C components, the molar (or mass) flow rate in the feed, n i (F), is equal to the sum of the product molar (or mass) flow rates, n i (P) for that component in the N product phases, p. To solve the above equation for the n i (P) from specified values of n i (F), we need an additional N−1 independent expressions involving n i (P). For example, if a feed mixture containing C components is separated into N product phases,[C(N-1)] additional expression. F COMPONENT RECOVERIES AND PRODUCT PURITIES

3. Dr Saad Al-ShahraniChE 201: Introduction to Chemical Engineering  For a sequence of distillations, a mixture is separated into a bottoms mixture, and a distillate mixture.  The concentration of species ( i ) in the product flow of the bottoms or distillate is related to the input concentration through a split fraction (SF) for component ( i ) in separator K. COMPONENT RECOVERIES AND PRODUCT PURITIES

4. Dr Saad Al-ShahraniChE 201: Introduction to Chemical Engineering Where: molar flow rate of species (i) in the first product in separator k. molar flow rate of species (i) in the feed in separator k. K 1 2 FiFi  Split fraction (SF) depends on: (1) Component thermodynamic and transport properties in the vapor and liquid phases, (2) Number of contacting stages. (3) Relative vapor and liquid flows through the column. COMPONENT RECOVERIES AND PRODUCT PURITIES

5. Dr Saad Al-ShahraniChE 334: Separation Processes SF =1, signifies that separation operation has successfully removed essentially all of component (i) into a particular product stream. Split Ratio (SR): It is the ratio between the amount of component in two different product streams. There are other measure of separation ability such as separation power (separation factor). Other measures are the product purity, and the overall percent recovery. COMPONENT RECOVERIES AND PRODUCT PURITIES

6. Dr Saad Al-ShahraniChE 334: Separation Processes K=1 K=2K=3 56.0175.5 501.5 234.1 445.5 270.0 Example COMPONENT RECOVERIES AND PRODUCT PURITIES

7. Example

8. Dr Saad Al-ShahraniChE 334: Separation Processes COMPONENT RECOVERIES AND PRODUCT PURITIES

9. Dr Saad Al-ShahraniChE 334: Separation Processes COMPONENT RECOVERIES AND PRODUCT PURITIES

10. Dr Saad Al-ShahraniChE 334: Separation Processes COMPONENT RECOVERIES AND PRODUCT PURITIES

11. Dr Saad Al-ShahraniChE 334: Separation Processes COMPONENT RECOVERIES AND PRODUCT PURITIES