Page 117 - Handbook of Energy Engineering Calculations

According to an article in The New York Times,* using data from Princeton
Plasma Physics Laboratory and The Energy Information Administration, the
daily waste from a 1000-MW electric-generating plant using 9000 tons of
coal per day is 30,000 tons of CO , 600 tons of SO , and 80 tons of NO. A
2
2
nuclear fission plant using 14.7 lb (6.67 kg) of uranium produces 6.6 lb (2.99
kg) of highly radioactive material. The projected nuclear fusion plant using 1
lb (0.454 kg) of deuterium and 1.5 lb (0.68 kg) of tritium produces 4.0 lb (1.8

kg) of helium.
A large demonstration project is expected to begin operating in
approximately 2030. The commercial fusion reactor is expected in
approximately 2050. Thus, while the fusion reactor has great promise, its

commercial utilization is expected to take many years to develop. At this
writing, the consensus is that both fission and fusion nuclear power will find
use during the 21st century.

kW OUTPUT OF EXTRACTION STEAM TURBINE

2
An automatic extraction turbine operates with steam at 400 lb/in absolute
(2760 kPa), 700°F (371°C) at the throttle; its extraction pressure is 200 lb/in 2
2
(1380 kPa) and it exhausts at 110 lb/in absolute (760 kPa). At full load
80,000 lb/h (600 kg/s) is supplied to the throttle and 20,000 lb/h (150 kg/s) is

extracted at the bleed point. What is the kW output?

Calculation Procedure:

1. Determine steam conditions at the throttle, bleed point, and exhaust
Steam flow through the turbine is indicated by “enter” at the throttle,
“extract” at the bleed point, and “exit” at the exhaust, as shown in Fig. 38a.
The steam process is considered to be at constant entropy, as shown by the

vertical isentropic line in Fig. 38b. At the throttle, where the steam enters at
2
the given pressure, p = 400 lb/in absolute (2760 kPa) and temperature, t =
1
1
700°F (371°C), steam enthalpy, h = 1362.7 Btu/lb (3167.6 kJ/kg) and its
1
entropy, s = 1.6398, as indicated by Table 3, Vapor of the Steam Tables
1
mentioned under Related Calculations of this procedure. From the Mollier