In the processing of the antibiotic streptomycin, the drug is purified to 50 wt% in water. For application, including IV drips, the streptomycin must be diluted and a preservative must be added. The diluent stream contains 2 wt% NaCl in water. The preservative stream contains 10 wt% preservative and 5 wt% NaCl in water. These three streams are mixed together in a mixing tank. The outlet stream is ready for packaging in IV bags.
a. Determine the ratio of the mass flow rate of the diluent stream to the outlet stream, given the drug is 10 wt% and the preservative is 3 wt% in the outlet stream.
b. Calculate the mass flow rates of the three inlet streams.
c. What is the wt% of NaCl in the outlet stream?