What options are being used to reduce the environmental effects of burning coal?

• A. Cleaning, solvent refining, gasification, liquefaction, and scrubbers.
• B. Nuclear power, solar cells, wind turbines, tidal energy.
• C. Mercury emissions.
• D. Deforestation.

Answer: (A)

Cleaner coal technologies and pollution-control measures are used to reduce environmental effects of burning coal. Cleaning coal, or coal washing, removes minerals and sulfur before combustion, which lowers sulfur dioxide and particulate emissions when the coal is burned. Solvent refining is another preparatory process that reduces impurities in the coal or its derivatives, helping to lessen pollutants released during use. Gasification converts coal into a cleaner-burning gas, allowing pollutants to be removed from the gas before combustion in a power plant. Liquefaction turns coal into liquids, which can be treated to reduce impurities before they are burned as fuels. Scrubbers, or flue-gas desulfurization systems, scrub sulfur dioxide from exhaust gases after combustion, cutting acid rain–forming emissions. Together, these approaches represent ways to lessen the environmental impact of coal use, rather than switching to other energy sources or focusing on emissions alone.