Sulfur Emission Trends and Forecast
Data compiled, analyzed, and presented by:
Presented on May 1, 2006
Sustainable Air Quality
Professor R. Husar
This presentation was designed to give a brief
overview of the trends of SOx Emissions with
respect to different sectors as well as different
fuel types. Each of the following charts give
specific representation of energy data gathered
from 1940 to 2002 along with a forecast up to
the year 2050.
Relevance to Energy Consumption
Sulfur emissions are a harmful pollutant
produced during the combustion of fossil fuels.
The fuels are separated into five different
categories for analysis in order to track the
amount of emissions produced by each:
Energy production is the main reason these fuels
are burned and thus sulfur emissions are the direct
by-product of this process.
As a result, energy consumption and sulfur
emission are very closely connected and the
analysis of energy consumption will help to shed
light on emission trends.
A perfect example of this connection is seen when
measuring energy efficiency since energy efficiency
determines the percentage of energy lost to
This category is comprised of emissions from
commercial businesses and residential homes.
The major sources of emissions in this category
• electric utilities
• a minimal amount from oil and
• virtually nothing from natural gas.
The emissions from commercial/residential result
entirely from the energy production for homes
The industrial sector includes:
• Chemical & Allied product mfg.(both organic and
• petroleum refineries & related industries (oil & gas
manufacturing, natural gas, and fluid catalytic cracking
• Metal processing (non-ferrous, copper, lead, aluminum)
• Wood, pulp & paper
• Mineral products
• Cement manufacturing
• Waste disposal and recycling
The emissions resulting from industrial activity:
• Mostly from coal combustion since older
factories use coal to produce a majority of
• Slightly less than coal from oil
• The remainder from gas and also from
industry's allocated amount of electric utility.
This sector includes:
• On-road vehicles (motorcycles, light duty gas
vehicles, light duty gas trucks, heavy duty gas
trucks, and diesels)
• Non-road vehicles (non-road gas, non-road
diesel, aircraft, marine vessels, and railroads)
• Non-road others (agriculture & forestry, other
combustion, and fugitive dust).
From greatest to least the contributors in
this sector are:
• Diesel engines
• Marine vessels
• Light duty gas vehicles & motorcycles
• Light duty gas trucks
• Heavy duty gas trucks
Vehicles are used to convert energy into
motion in order to transport people and
things. This energy produces sulfur
emissions mainly through the combustion
of gasoline and diesel fuels.
FUEL COMB. ELEC. UTILTIES
SO2, 1000 Tons/yr
1900 1950 2000 2050
El. Util CoalTot OilTot
GasTot OtherTot Coal Project.
Oil Project. Gas Project. El. Util Project.
Shows the SOx emission from the use of coal, gas, and oil for Electrical Utilities. Coal is clearly the
largest contributor in this section, producing nearly all of the total electric utility emissions. The
emissions peak in 1977 and again in 1984. This plot is particularly important because the electric
utilities sector contributes to a majority of the total SOx emissions since the 1950's
Shows the SOx emissions for the combined industrial industry. This includes coal, gas, and oil, with
coal being the greatest contributor. There has been a seemingly steady decline in the emissions with
a peak in 1970; however the emissions from gas have been increasing since 1975. The emissions
from oil have been decreasing since 1981.
Shows the SOx emissions from the manufacturing of Chemicals, Sulfur compounds, agricultural
chemical, and other chemical manufacturing. There are very little emissions coming from the
agricultural chemical manufacturing. The biggest contributor is from Chemical, then from Sulfur
compounds. There is a peak in the emissions in 1970, and from 1984 to 1989. Emissions have been
increasing again since 1998 with a hint of leveling off since the past few years.
Shows the SOx emissions from processing copper, lead, and ferrous metals. Copper is the largest
contributor, with very little being contributed from lead and ferrous metals. There is a large increase
in emissions from copper in 1970 with the emissions decreasing ever since.
Shows the SOx emissions from petroleum, petroleum refineries, and other petroleum. There is a
large peak from the refineries section in the 1970, and in 1981 from other petroleum industries.
Shows the SOx emissions from cement manufacturing, the wood, pulp, & paper industry, and from
other industrial processes. The component entitled “OtherInd” represents the total emissions for this
section. There is a peak in 1978 in both the cement manufacturing and the wood, pulp & paper
industry. It can be seen that there was an enormous decline just after this peak in the cement
Shows the SOx emissions from on-road vehicles. This includes light-duty gas vehicles &
motorcycles, light-duty gas trucks, heavy-duty gas vehicles, and diesel. There is a peak in 1990 for
diesels. Light-duty gas trucks have been steadily climbing since 1973 and currently contribute to a
significant amount of the total whereas before 1973 they contributed virtually nothing to the total.
Shows the SOx emissions from non-road vehicles. This sector includes marine vessels, railroads, and
non-road diesel. There was a major drop in railroads in 1960 which caused a major decrease in the
overall emissions. Since then there has been a slow but steady increase in all sectors since 1971.
Shows the total SOx emissions for each sector. This includes the electric utilities, industrial,
residential and commercial, transport, and metals. Electric utilities peaked in 1977 and have been
decreasing ever since. There is a small increase in 1971 for the industrial and metals sector.
The trends show that all sectors are
decreasing in SOx emissions.
This is a result of better technology and
the consumption of cleaner fuels
regardless of increased consumer demand.