Clean Coal Technology
As previously mentioned under the Electric Cars page, electric cars can be made into an even cleaner mode of transportation if Clean Coal Technology (CCT) is used.
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Clean Coal Technology Methods
There are four clean coal technologies. These include pre combustion, combustion, post combustion, and conversion. Pre combustion is the process of cleaning coal before it is burned. Different ways of cleaning the coal include physically, column flotation, chemically, or biologically. The second technology, combustion, cleans coal while it is inside the furnace. By burning the coal in a furnace it prevents the formation or escape of pollutants. A type of combustion cleaning technology that is most common is fluidized bed combustion. This process grinds coal into particles, mixes them with limestone, and then injects them with hot air. As the air burns the coal, the limestone captures sulfur emissions. The water tubes collect the heat that is generated and form steam. The steam then produces electricity. This technology reduces sulfur emissions by 90 percent. The third technology, post combustion, are techniques used after the coal is burned. This cleans the air before it goes through the smokestacks and is released into the atmosphere. The final technology is conversion. In this process, coal is turned into a liquid or gas that can be cleaned and used as fuel. |
CCTs Effect On Pollutants
Most coal plants have installed clean coal technologies and the result they have on pollutants is substantial. Three of the main pollutants released while coal is burned are sulfur dioxide (SO2), nitrogen oxides (NOx), and particulate matter. SO2 is the most produced pollutant from the burning of coal. SO2 causes damaging acid rain. About 14,100 tons of SO2 are emitted each year by a typical coal plant. However, if CCTs are put into place then these emissions can be reduced to 7,000 tons. NOx are also produced from the burning of coal. NOx cause ground level ozone which can burn lung tissue, worsen asthma, and make people more susceptible to respiratory diseases. An uncontrolled coal plant typically emits 10,300 tons of NOx per year. Once CCTs are put into place then that number drops to about 3,300 tons per year. A third pollutant that is emitted from the burning of coal is particulate matter. A coal plant with no CCTs emits about 500 tons per year. If CCTs, such as baghouses, are used then up to 99 percent of these particulates can be captured. |
Other Methods to Reduce Emissions
There are many ways to reduce emissions while still having the same amount of electricity produced as before. First, fuel switching is the idea of switching to a lower carbon fuel such as natural gas or biomass. By switching to natural gas fewer CO2 emissions are released which makes the burning more efficient. Also, biomass is a good option because it is a renewable fuel that naturally reduces CO2 emissions. Another way to reduce emissions is to use a different energy source for electricity. Wind and solar power are both clean energy sources and if used correctly they will produce the same amount of electricity as coal. |