Transcript Document 7796897

2. Describing the flow of air inside a duct.
Air passes through a 10 inch-ID duct at 250F and 100 psig.
The velocity is found to be uniform and equal to 25 ft/sec.
Compute the mass flow rate (lbm/min) and the volumetric
flow rate in acfm and scfm.
3. Pollutant concentration and emission rate.
An exhaust vent from a plastics manufacturing plant discharges at 100 acfm of
air at 200C, 90 kPa. A continuous emissions monitor shows that the
discharge contains 5 ppm of phenol vapor. This value (5 ppm) is close to
the odor threshold and the community can be expected to detect the
medicinal, sweet odor of the phenol. The molecular weight of phenol is
94.1. What is the actual phenol concentration in the exhaust stream, and
what is the emission rate of phenol to the atmosphere?
4. The exhaust gas from an automobile contains 1.5 percent by volume of
carbon monoxide. What is the concentration of CO in milligrams per cubic
meter (mg/m3) at 25C and 1 atm pressure? What is the concentration in
ug/m3 in the exhaust pipe if it is at 200C and 1.1 atm of pressure?
5. The average daily concentration of sulfur dioxide is observed to be 415
ug/m3 at 25C and 1 atm. What is the concentration of SO2 in parts per
million?
6. The ozone concentration is observed to be 118 ug/m3 at an urban
monitoring stations. Does this value exceed the concentration found in
standard dry air (0.01-0.04 ppm)?
7. The maximum concentration of dust in the atmosphere during 24-hour
period was found to be 0.000130 grains per dry standard cubic foot
(gr/dscf). What is the equivalent concentration in micrograms per cubic
meter? (1gr/ft3 equals to 2.29 g/m3)