Engineering Economy 7th Edition by Leland Blank ,Anthony Tarquin

تمرين 21

A metallurgical engineer has estimated that the capital investment cost for recovering valuable metals (nickel, silver, platinum, gold, etc.) from the copper refinery's wastewater stream will be $12 million. The equipment will have a useful life of 15 years with no salvage value. Its operating cost is represented by the relation ($2,600,000)E 19 , where E is the efficiency of the metal recovery operation (in decimal form). The amount of metal currently discharged is 2880 pounds per year prior to recovery operations, and the efficiency of recovery is estimated at 71%. What must the average selling price per pound be for the precious metals that are recovered and sold in order for the company to break even at its MARR of 15% per year