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Updated: Aug 5, 2026
11:14
Two-way Valorization of Blast Furnace Slag: Synthesis of Precipitated Calcium Carbonate and Zeolitic Heavy Metal Adsorbent
Published on: February 21, 2017
[Retention of selenium volatility using lime in coal combustion]
1School of Chemical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China. jychang63@263.net
Huan Jing Ke Xue= Huanjing Kexue
|August 18, 2001
Summary
Adding lime (calcium oxide) effectively reduces selenium volatility during coal combustion. This method significantly decreases selenium in fly ash and chimney leachate, especially in circulating fluidized bed (CFB) combustion.
Area of Science:
- Environmental Chemistry
- Combustion Science
- Geochemistry
Context:
- Coal combustion releases volatile elements, including selenium, posing environmental risks.
- Understanding selenium's behavior during combustion is crucial for emission control.
- Exchangeable cations in coal influence selenium volatility.
Purpose:
- To investigate selenium volatility during coal combustion.
- To determine the effect of coal's exchangeable cations on selenium release.
- To evaluate the efficacy of calcium oxide (lime) in retaining selenium.
Summary:
- Selenium volatility exceeded 97% at 815°C, influenced by exchangeable cations at lower temperatures.
- Lime addition significantly restrained selenium volatility in both fixed bed and circulating fluidized bed (CFB) combustion.
- In CFB combustion, lime altered selenium partitioning in ash and drastically reduced chimney emissions and leachate selenium concentrations.
Impact:
- Lime is an effective agent for selenium retention during coal combustion, particularly in CFB systems.
- This research provides insights for developing cleaner coal combustion technologies.
- Reduced selenium emissions mitigate environmental contamination and health risks associated with coal-fired power plants.
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