2. Describing the flow of air inside a duct.

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• 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.

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• 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?

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• 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?

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• 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?

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• 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)?

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• 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)