1. Repeat Exercise 10.10 for the following cases:
The superheater provides steam at 600°F and 600 psia
ii. The discharge pressure from the turbine is 300 psia
Figure 10.30 Superheater and turbine.
l'igure 10.30 Superheater and turbine
For both cases (i) and (ii), calculate
a) Isentropic efficiency of the turbine
b) Lost work for the process
c) Thermodynamic efficiency of the process
2. Complete Exercise 10.11 in the text. Note - disregard heat flow to the
3. Complete Exercise 10.21 in the text. Use the RSTOIC model in ASPEN PLUS to
determine the results operating in both adiabatic and isothermal mode. Assume a
pressure drop of 0.1 bar across the reactor. The stoichiometry for the reaction is:
10.10 ,000 IL hr of salurated walet al 600 psia is superhiaated to 650 F and expanded aeross lurbine to 200 psia as illustrated in
a. Isentropic efficiency of the turbine
h. ost work for the process
c. efficiency of the process
Tigure 10.30 Superheater and turbine.
10.11 Superheated steam at 580 F and 500 psia is expanded across turbine, as shown in l'igure 10.34 to 540 F and 400 psia. 0.9 kW of shaft work
is produced. The turbine exhaust is coolod by 77 F reservoir to its dew point at 400 psia.
Figure 10.31 Turbine and cooler.
Flowrate of steam in 1b /hr
b. of the Lurbine
e. Lost work
d. Thermodynamic efficiency
10.21 A reactor is to be designed lor the oxidation of sullur dioxide. with excess oxygen from air, to sullur trioxide. The entering leed, al 550 K and
1.1 bar consists of 0.219 kmol/s of nitrogen, 0 058 kmol/s of oxygen, and 0 028 kmol/s of sulfur dioxide. The fractional conversion of sulfur dioxide
50%. The reaction is very cxothermic. Three cases are to be considered:
a. Adiabatic reaction
b. IsoLhetinial reaction with the heal of reaction transferred to boiler leed water al 100*C
c. Isothermal reaction with the heat of reaction transferred to boiler feed water at 200' C