BEM 4351 - Unit VII Assessment.pdf - BEM 4351 Environmental...

Info icon This preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
BEM 4351 Environmental Technology Unit VII Assessment Write an essay consisting of at least 500 words addressing ALL of the following topics (a. through k.): a. What are the primary three gases comprising the atmosphere? b. Explain how temperature varies with altitude. c. Describe the environmental lapse rate. d. Why are sulfur dioxide, carbon monoxide, and lead of such importance that they are criteria pollutants under the NAAQS? e. What is the range of particle size for fly ash? f. Explain the greenhouse effect. g. Describe carbon capture and sequestration. Do you think it is viable? h. Discuss the operation of a high volume sampler. Why does it need an air pump? i. If the concentration of carbon monoxide is 2.9% at a location along the highway at 70oC, what is the concentration in ppm? j. Describe three air pollution control strategies listed on page 374 of our textbook. k. Explain the operation of a wet scrubber. Question (a.) What are the primary three gases comprising the atmosphere? Answer (a.) The atmosphere is a mixture of many different gases, but the air we breathe mostly consists of molecular nitrogen and oxygen. About 78 percent of unpolluted dry air is nitrogen and about 21 percent is oxygen. This nitrogen and oxygen combined make up approximately 99 percent of the atmosphere. The remaining 1 percent of filtered dry air is a mixture of several other gases. Most of that remaining 1 percent (about 0.9 percent) is the inert gas argon. The rest of it includes carbon dioxide, methane, hydrogen, helium, neon, ozone, and numerous other gases in trace (very small) amounts. (Nathanson & Schneider, 2015, pg.346) Question (b.) Explain how temperature varies with altitude. Answer (b.) Using the first law of thermodynamics, scientists have calculated a theoretical dry adiabatic lapse rate. Regardless of what the actual air temperature profile may be, a moving parcel of air always cool down 1°C for each 100 m it rises in the atmosphere and will warm up 1°C for every 100 m it sinks. This dry adiabatic lapse rate is calculated on the assumption that there is no moisture or water vapor in the air. Water, usually present in the atmosphere to some degree, emits or absorbs heat as it condenses or evaporates. As air rises, condensation occurs, producing a slower cooling rate (lower lapse rate) than for dry air. The average wet adiabatic lapse rate is about 6.5°C per km (3.5°F per 1000 ft). (Nathanson & Schneider, 2015, pg.348) Question (c.) Describe the environmental lapse rate. Answer (c.) Atmospheric stability depends on the rate of change of air temperature with altitude, that is, on the temperature gradient (or profile) that may prevail at a particular time and location. Normally, air temperatures in the troposphere decrease with increasing altitudes. But the rate at which the air temperature drops, called the environmental lapse rate, is of crucial importance with regard to atmospheric stability. Environmental lapse rate is also called prevailing or ambient lapse rate.
Image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern