Chapter 4, Problem 4.50P

Following is a diagram of the shirt-cleaning process used by the Roods of Suds One-Day Laundry Sendees. Inc. The shirts are soaked in an agitated tub containing Whizzo, the Wonder Detergent, and are then wrung out and sent to a rinse stage. The dirty Whizzo is sent to a filter in which most of the din is removed, and the cleaned detergent is recycled back to join a stream of pure Whizzo, with the combined stream sening as the feed to the washtub.

Wh

Dirty shirts

H

| Clean shirt* Pure Wh 97* Wh AGITATED

TLB87* Wh8* Wh FILTER Recycled Wh

Data:

1. Each 100 lb_m of dirty shirts contains 2.01b_m of dirt
2. The washing removes 95% of the dirt in the dirty shirts.

For each 100 lb_m of dirty shirts. 25 lb,„ of WTfizzo leaves with the clean shirts, of which 22 lb_n, is wrung back into the tub.

The detergent that enters the tub contains 97% Whizzo. and that which enters the filter contains 87%. The wet dirt that leaves the filter contains 8.0% Whizzo.

How much pure Whizzo must be supplied per 1001b_ra of dirty shirts?

What is the composition of the recycled stream?