An evaporation-crystallization process is used to obtain solid potassium sulfate from an aqueous solution of salt. The fresh feed to the process contains 19.6 wt% K2SO4. The wet filter cake consists of solid K2SO4 crystals and a 40.0 wt% K2SO4 solution, in a ratio 10 kg crystals/kg solution. The filtrate, also a 40.0% solution, is recycled to join the fresh feed. Water is fed into the evaporator at a rate of 389 kg water/s. The evaporator has a maximum capacity of 175 kg water evaporated/s. Required:
a. Assume the procces is operating as maxiumum capacity. Draw and label a flowchart and do the degree-of-freedom analysis for the overall system, the recycle-fresh feed mixing point, the evaporator, and the crystallizer. Then write in an efficient order (minimizing simultaneous equations) the equations you would solve to determine all unknown stream variables. In each equation, circle the variable for which you would solve, but don't do the calculations.

b. Calculate the maximum production rate of solid K2SO4, the rate at which fresh feed must be supplied to achieve this production rate.