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Which toxic elements can be released when coal is burned?
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coal utilization
Cross-regenerative coke oven. (A) Cross section, showing the alternating arrangement of flue walls and ovens; (B) longitudinal section, showing (left) a series of combustion flues in a single flue wall and (right) part of a long, slotlike oven.
When coal is burned, various trace elements originally present in the fuel are released into the environment. These toxic substances can be categorized by how they behave during the combustion process:
- Volatile elements: Some elements escape as gases during burning, including chlorine and mercury.1
- Elements concentrated in ash: Other elements remain and become concentrated in the solid combustion by-products, such as bottom ash and fly ash, including arsenic and barium.1
Beyond these trace elements, the combustion of coal also produces sulfur and nitrogen oxides, which contribute to acid rain, as well as particulate matter and carbon dioxide, a major driver of global warming. It is an ethical imperative to manage these hazardous emissions and waste products responsibly to protect public health and the environment, as the release of such pollutants poses significant risks to ecosystems and human populations.1