EENV 444 Air Pollution Control II: Test \# 2, Take Home Test: Fall 2024.
No group or consulting allowed.
Due on Dec 3, 2024, Tuesday in class 9:30 am or earlier.
Make appropriate assumptions when needed and justify
1.0 A 1000 MWe coal fired powerplant burns \( 12,500 \mathrm{Btu} / \mathrm{lb} \). coal containing \( 2.5 \% \) sulfur and 150 ppb of mercury. You are asked to determine the efficiency of control system required to meet the NSPS (Based on energy output) for SO2 and Mercury. Also suggest the type of control systems you would recommend in order to meet the emission standards of SO2 and Hg . The thermal efficiency of the powerplant is \( 38 \% \). If the coal contains \( 60 \% \) carbon, what will be the amount of CO2 emitted per day (tons) from this powerplant.
Following steps are used for grading your answers:
a) Identify the Emission Standards for SO 2 and Hg ( based on energy output) (3)
b) Determine the efficiency required to meet the above standards. Please show all your calculations (5)
c) Justify the type of control system you have chosen to meet the standards. (2)
d) Determine the amount of CO2 emissions and a brief note on its effect on climate change (2)
2.0 The company decided to use limestone FGD process to control the SO2 emissions from the above power plant with 95\% removal of sulfur dioxide. You are a new engineer and you are asked to determine the amount of solid sludge created by the limestone process. The limestone available is at \( 95 \% \) purity ( \( 5 \% \) inert) and the process needs \( 15 \% \) excess limestone. Also determine the amount of energy required to run the main fan and for pumping the sludge, given the following information: Every pound of coal burned produces 16 pounds of exhaust with a MW of 29 and the L/G ratio is 70 gallons per 1000 scf. The sludge has to be pumped with a 100 feet head loss to store it in the pond. The sludge has a specific gravity of 1.15. Fan efficiency is 0.7 and the fan pressure drop is 12 inches of H 2 O . The pump efficiency is 0.7 .
Steps used to grade your answer are:
a) identify equation to estimate the amount of limestone needed, theoretical and actual (4)
b) identify the amount of waste stream, solids and liquids (4)
c) Total Hp required for the fan, pump and heating the flue gas (4)
3.0 A 2 feet diameter packed tower packed with 1-inch ceramic Raschig rings, with a gas to liquid mass flow ratio of 1, is treating a gas stream containing \( 1.5 \% \) ammonia (volume basis). The outlet ammonia concentration shall not exceed \( 0.1 \% \) by volume to meet the EPA requirements at the exit gas stream of the tower. The tower is working at 100 F and 1
