Assume the wastewater, (Flow = 100 L/min, Cin = 100 mg/L, and k = 0.4 per minute) is to be treated by three equal-volume CSTRs in series. Calculate the total volume of those CSTRs (keep in mind that each of the three is identical) to achieve the desired effluent concentration of 5 mg/L.

Aseries piping system conveys methyl alcohol. the system consists of 70 m of 1- nominal pipe follow by 50 m of 2-nominal pipe, both schedule 40 commercial steel. the 1-nominal pipe contains 3 90° elbows (regular) anda fully open gate valve, all threaded. the pressure drop through the system is 150 kpa. determine the volume flow rate through the system that is horizontally laid.