4.20 A commercial steel schedule 40 pipe (class 300) is being used to transport liquid cyclohexane at 70°F, 80 psia at a volumetric flow rate of 1000 gpm.

The fittings, valves, supports, and pump are estimated to cost 6.9 times the installed pipe cost per foot. Annual maintenance is estimated to be 2% of the installed pipe costs per foot. The pump in the system runs 12 h/day, 260 days per year. The efficiency of the pump is estimated to be 68%. The cost of energy is 0.09 $/kW·h. The pipeline is expected to have a 50-year life and a rate of return of 20%. Use an inflation rate of 1.5% to adjust the value of C1 from Table 4.10 to 2012 dollars.

a. Determine the economic diameter and specify the standard pipe size that results in the minimum system cost.

b. Determine the economic velocity of the fluid (ft/s).

c. Construct the cost curves for this scenario assuming that the friction factor can be assumed constant at the value computed for the economic diameter from part (a). Your plot should look similar to Figure 4.9.