3.2 Consider the wastewater minimization problem described by Polley and Polley (2000). The process has four sources and four sinks and information concerning them can be seen in Tables 3-9 and 3-10. a Find the targets for minimum fresh water and minimum wastewater discharge after direct-recycle. b Develop a recycle strategy that attains the identified targets. TABLE 3-9 SINK DATA FOR PROBLEM 3-2 (POLLEY AND POLLEY (2000)) Sinks Flow Maximum inlet Load (tonnes/h) Concentration (ppm) (kg/h) 1 50 20 1 2 100 50 5 3 80 100 8 70 200 14 TABLE 3-10 SOURCE DATA FOR PROBLEM 3.2 (POLLEY AND POLLEY (2000)) Sources Flow Concentration Load (tonnes/h) (ppm) (kg/h) 1 2.5 2 100 100 10 3 70 150 10.5 4 60 250 15 50 50