Coal burned in power plants in the United States has a energy content of approximately 24 kJ/g and an average carbon content of about 62 percent (by wt). For almost all new coal plants, Clean Air Act emission standards limit emissions of sulfur dioxide (SO2) to 260 grams per million kJ of heat input (fuel value). They also restrict particulate emissions to 13 g/106 kJ.
Suppose the average plant burns fuel with 2% sulfur content (by wt) and 8% unburnable minerals called "ash." About 70% of the ash is released as "fly ash" and about 30% settles out of the firing chamber and is collected as "bottom ash." Assume that this is a typical coal plant with 3 units of heat energy required to deliver 1 unit of electrical energy.
a) Calculate the emissions of sulfur dioxide, particulates (fly ash), and carbon dioxide per kilowatt-hour of electrical energy produced. Assume that all of the carbon in the coal is released to the atmosphere.
b) Calculate the efficiency (percent removal) of the sulfur emission control system required to meet the sulfur emission limitations.
c) Calculate the efficiency of the particulate emission control system required to meet the particulate emission limitations.