*Coal often contains sulfur as an impurity that is released as gaseous SO2 during combustion. SO2 is one of six primary air pollutants monitored by the U.S. EPA. The Clean Air Act limits sulfur emissions from large coal-fired boilers to 0.54 kg (1.2 lbs) of sulfur per million Btus of heat generated. (1 metric ton=1,000 kg=2,200 lbs=1.1 tons; 1 kg=2.20lbs).
1. Given that coal used by electric power plants has a heating value of 27.5 million Btus per metric ton, determine the number of kg of coal needed to produce 1 million Btus of heat.
2. Assuming that all the sulfur in the coal is released to the atmosphere during combustion, what is the maximum percentage of sulfur the coal can contain and still allow the utility to comply with the Clean Air Act?
*Under normal driving conditions, an internal combustion engine produces approximately 200 grams (0.2 kilograms or 0.44 pounds) of CO2 per kilometer driven. In one large city, there are 7 million cars, and each car is driven an average of 20,000 kilometers (12, 400 miles) per year.
3. Calculate the carbon footprint per car, the number of metric tons of CO2 produced by a typical car in one year.
4. Calculate the total carbon footprint for all cars in the city, the metric tons of CO2 produced by all cars in one year. (1 metric ton=1,000 kg=1.1 tons). Worth 10 points.
*This information from an EPA report shows the typical composition of U.S. municipal solid waste (MSW) in 2006.FE 11
Yard trimmings 14%
Food Scraps 13%
Glass Plastics 6%
Rubber, leather and textiles 8%
The average daily MSW production per person in the US in 2006 was 2.10 kilograms (4.60 pounds).
5. Use the data in the figure above to understand what makes up the annual MSW ecological footprint for a typical American. For each category in the pie chart, calculate the total weight in kilograms (and pounds) generated in 2006 by the average American. (1 kilogram = 2.20 pounds)