Page 112 - Handbook of Energy Engineering Calculations

Find the theoretical reduction in straight-condensing (no regenerative heaters)
heat rates from Fig. 34. Enter the bottom of Fig. 34 at the inlet steam
temperature, 800°F (426.7°C), and project vertically upward to the 1000-
2
lb/in (abs) (6895-kPa) 1-inHg (3.4-kPa) backpressure curve. At the left, read
the reduction in straight-condensing heat rate as 14.8 percent.
Next, enter Fig. 34 at the bottom of 70 percent of maximum possible rise
in feedwater enthalpy, and project vertically to the three-heater curve. At the
left, read the reduction in straight-condensing heat rate for the number of

heaters and actual enthalpy rise as 0.71.

FIGURE 34 Reduction in straight-condensing heat rate obtained by

regenerative heating.