Let us consider a column consisting of ideal plates. If we are somewhere at nth plate as shown in figure below, the plate immediately above the plate is n-1 and immediately below is n+1. Subscripts are used on all quantities showing the point of origin of the quantity.
Two fluid stream enters the plate
- Stream of liquid Ln-1 mol/h from plate n-1
- Stream of vapor Vn+1 mol/h from plate n+1
Two fluid stream leaves the plate
- Stream of liquid Ln mol/h descends to plate n+1
- Stream of vapor Vn mol/h rises to plate n-1
Concentration of liquid and vapor phase are denoted by ‘x’ and ‘Y’ respectively. Then concentration of stream entering the plate becomes
- Vapor entering plate Yn+1
- Liquid entering plate Xn-1
Concentration of stream leaving the plate becomes
- Vapor leaving plate Yn
- Liquid leaving the plate Xn
Name : Pratiksha Shrestha
Ms. Shrestha holds masters degree in food engineering and bioprocess technology from Asian Institute of Technology (AIT) Thailand. She is currently working for Government of Nepal at Department of Food Technology and Quality Control (DFTQC), Kathmandu. She is also a teaching faculty in College of Applied food and Dairy Technology (CAFODAT) affiliated to Purbanchal university, Nepal.