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Exercise review

Exercise review

by Pivato Alberto -
Number of replies: 0

TEXT

A power plant operates with 800 ppm NOX in the flue gas. The flue gas flow rate is 150000 m3/h at 300°C and 1 atm. An SCR system is being designed for 75% removal of NOx. Calculate the stechiometric amount of ammonia required in kg/day.

R= 8.20573E-05 m3 atm K−1 mol−1

MW NO= 30.01 g/mole

MW NO2= 46,01 g/mol

MW NH3 =17.031 g/mole

SOLUTION

Volume= 1.50E+05 m3/h

T=300    °C

Preassure= 1 atm

Assuming that NOX is represented by the 100% of NO2

n=(P*V)/(R*T)

Flow NO2=2552.1 moli/h → 2552.1 *46/1000 = 117 kg/h      

Efficiency = 0.75

8/6 moles of NH3 is required per 1 moles of NO2.

Amount of ammonia =0.75*8/6*(2552.1*17.031)*24/1000=1043 kg/day