Question

An unvented kerosene heater is operated for 1 hr in an apartment
having a volume of 200 m^{3}. The heater emits
SO_{2}at a rate of 50 µg/s. The ambient air
concentration (C_{a}) and the initial indoor air
concentration (C_{0}) of SO_{2} is 50 ppb (P= 1
atm, T_{indoor}=20°C,
T_{outdoor}=5°C). The ventilation rate in the
apartment is 0.9 air changes per hour. If the apartment
is well-mixed, what is the indoor air concentration of
SO_{2} in µg/m^{3} at the end of 1 hr if the decay
rate for SO_{2} is 6.39 × 10^{−5}
s^{−1}?

Answer #1

An unvented, portable heater fueled with kerosene is tested
under controlled laboratory conditions. After running the heater
for two hours in a test chamber with 46.0 m3 volume and ventilation
rate of 11.5 m3/h, the concentration of carbon monoxide (CO)
reaches 20 mg/m3. The initial CO concentration in the lab is zero,
and the ambient CO level is negligible throughout the test.
a. Find the rate at which the heater emits CO.
b. If the heater is used in a...

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NO can be treated as a conservative pollutant.
a) What is the NO source strength of the heater (mg/hr)?
b) The heater runs for one hour and then is turned off...

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A factory dumps 5.0 m3/s of waste with a pollutant
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1) 20 kg/min water at 20º C is mixed adiabatically with 40
kg/min water at 80 ºC. What is the outlet water temperature?
Select one:
a. 80 °C
b. 60 °C
c. 50 °C
d. 70 °C
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Steam at 0.8 MPa and 500 ºC is throttled over a well insulated
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