This Is a Chemical Engineering question but that isnt among thesubjects

Problem 4.39 Felder and Rouseeau Elementary Principles OfChemical Processes 4th Edition

The hormone estrogen is produced in the ovaries of females andelsewhere in the body in men and post-menopausal women, and it isalso administered in estrogen replacement therapy, a commontreatment for women who have undergone a hysterectomy.Unfortunately, it also binds to estrogen receptors in breast tissueand can activate cells to become cancerous. Tamoxifen is a drugthat also binds to estrogen receptors but does not activate cells,in effect blocking the receptors from access to estrogen andinhibiting the growth of breast-cancer cells. Tamoxifen isadministered in tablet form. In the manufacturing process, a finelyground powder contains tamoxifen (tam) and two inactivefillers—lactose monohydrate (lac) and corn starch (cs). The powderis mixed with a second stream containing water and suspended solidparticles of polyvinylpyrrolidone (pvp) binder, which keeps thetablets from easily crumbling. The slurry leaving the mixer goes toa dryer, in which 94.2% of the water fed to the process isvaporized. The wet powder leaving the dryer contains 8.80 wt% tam,66.8% lac, 21.4% cs, 2.00% pvp, and 1.00% water. After someadditional processing, the powder is molded into tablets. Toproduce a hundred thousand tablets, 17.13 kg of wet powder isrequired. (a) Taking a basis of 100,000 tablets produced, draw andlabel a process flowchart, labeling masses of individual componentsrather than total masses and component mass fractions. It isunnecessary to label the stream between the mixer and the dryer.Carry out a degree-of-freedom analysis of the overall two-unitprocess. (b) Calculate the masses and compositions of the streamsthat must enter the mixer to make 100,000 tablets. (c) Why was itunnecessary to label the stream between the mixer and the dryer?Under what circumstances would it have been necessary? (d) Go backto the flowchart of Part a. Without using the mass of the wetpowder (17.13 kg) or any of the results from Part b in yourcalculations, determine the mass fractions of the stream componentsin the powder fed to the mixer and verify that they match yoursolution to Part b. (Hint: Take a basis of 100 kg of wet powder.)(e) Suppose a student does Part d before Part b, and re-labels thepowder feed to the mixer on the flowchart of Part a with an unknowntotal mass (m1) and the three now known mole fractions. (Sketch theresulting flowchart.) The student then does a degree-of-freedomanalysis, counts four unknowns (the masses of the powder, pvp, andwater fed to the mixer, and the mass of water evaporated in thedryer), and six equations (five material balances for five speciesand the percentage evaporation), for a net of −2 degrees offreedom. Since there are more equations than unknowns, it shouldnot be possible to get a unique solution for the four unknowns.Nevertheless, the student writes four equations, solves for thefour unknowns, and verifies that all of the balance equations aresatisfied. There must have been a mistake in the degree-of-freedomcalculation. What was it?