6.10 Investigate the effect of the separator pressure on the operating parameters of the boiler blowdown system described in Figure P6.9B. For this evaluation, vary the separator pressure from 20 to 100 psia and plot the following curves:

a. The annual energy cost savings as a function of the separator pressure.

b. The mass flow rate of the low-pressure process steam (lbm/h) and the volumetric flow rate of the dirty water (gpm) leaving the separator. Plot these on the same graph (using the plot overlay feature in EES). Use the left-hand axis to plot the low-pressure process steam mass flow rate and the right-hand axis to plot the dirty water volumetric flow rate.

c. Comment on the results of the parametric studies from parts

(a) and (b).