Assignment: Mathematical Principles in Environmental Engineering- Material Balances
I. Chemicals Addition/Dilution System
An aqueous solution of sodium hydroxide contains 20% NaOH by mass. It is desired to produce an 8% NaOH solution by diluting a stream of the 20% solution with a stream of pure water.
1. Calculate the ratios (g H2O/g feed solution) and (g product solution/g feed solution).
2. Determine the feed rates of 20% solution and diluting water needed to produce 2310 lbm/min of the 8% solution.
II. Simple Distillation Column
A mixture containing 45% benzene (B) and 55% toluene (T) by mass is fed to a distillation column. An overhead stream of 95 wt% B is produced, and 8% of the benzene fed to the column leaves in the bottom stream. The feed rate is 2000 kg/h. Determine the overhead flow rate and the mass flow rates of benzene and toluene in the bottom stream.
III. Two-Step Distillation Column
A labeled flowchart of a continuous steady-state two-unit distillation process is shown above. Each stream contains two components, A and B, in different proportions. Three streams whose flow rates and/or compositions are not known are labeled 1, 2 and 3.
Calculate the unknown flow rates and compositions of streams 1, 2, and 3.