A pickle producing plant produces and discharges a waste brine solution with a salinity of 13,000 mg/L NaCl at a rate of 0.14 MGD into a stream. Before the discharge enters the stream, the flow rate of the stream is 1.2 MGD and the salinity is 20 mg/L. Assume that you can model this as a CSTR.
What is the concentration of the mixture of the stream and the discharge directly below the discharge point?
Directly below the discharge point is a prime fishing spot and the fish are intolerant to salt concentrations above 200 mg/L. How much salt should be removed per day from the plant effluent stream in order to maintain a concentration of salt < 200 mg/L in the stream mixture?