One of the tried and true ways for organizing information about a process is to sketch a flowchart.
Typically, you use boxes to symbolize unit processes or process units and directed lines to represent material or information flows.
For example, think of a furnace: natural gas is mixed with air and burned while exhaust gas goes out the chimney.
As you draw the chart, you label as much information as you have -- flow quantities and compositions, stream conditions, etc. If you don't know a value, go ahead and assign a variable.
Often, the problem information will be in mixed units. You can look at your chart, see this, and decide which, if any, need to be converted.
Hint: It is usually smarter to work with mass or molar flows, so be prepared to convert out of volumetric units right away.
When you assign variables, it is usually smart to assign units as well (and write them down).
As you work the problem, add your findings to the chart -- it will help you keep track of what remains to be done.
The feed to a continuous still contains 20 mol% C6 and 80 mol% C11 hydrocarbons. The composition of the overhead distillate is essentially pure C6 and the bottoms contain 5 mol % C6 and the balance C11 materials. Sketch the flowchart.
References:
R.M. Price
Original: 9/6/96
Modified: 12/25/2004
Copyright 1996, 2004 by R.M. Price -- All Rights Reserved