Effect of CaO on leaching characteristics of arsenic in fly ash from fluidized bed coal combustion

JIAO Fa-cun; ZHOU Bo-han; YAN Yu-le; ZHOU Yu-hui; DONG Zhong-bing

Volume 42 Issue 05

May 2014

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Article Navigation > Journal of Fuel Chemistry and Technology > 2014 > 42(05): 534-538

JIAO Fa-cun, ZHOU Bo-han, YAN Yu-le, ZHOU Yu-hui, DONG Zhong-bing. Effect of CaO on leaching characteristics of arsenic in fly ash from fluidized bed coal combustion[J]. Journal of Fuel Chemistry and Technology, 2014, 42(05): 534-538.

Citation:

JIAO Fa-cun, ZHOU Bo-han, YAN Yu-le, ZHOU Yu-hui, DONG Zhong-bing. Effect of CaO on leaching characteristics of arsenic in fly ash from fluidized bed coal combustion[J]. Journal of Fuel Chemistry and Technology, 2014, 42(05): 534-538.

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Effect of CaO on leaching characteristics of arsenic in fly ash from fluidized bed coal combustion

1.
National Center of Coal Products Quality Supervision & Inspection, Huainan 232001, China;
2.
School of Chemical Engineering, Anhui University of Science and Technology, Huainan 232001, China

Received Date: 2013-10-25
Rev Recd Date: 2014-01-19
Publish Date: 2014-05-30

Abstract

Abstract

The leaching characteristics of arsenic in fly ash from coal combustion in lab-scale fluidized bed were clarified. Calcium oxide was mixed with fed coal for matching different Ca/S molar ratio to investigate the role of calcium on the leaching behavior of arsenic. The results indicate that increase in Ca/S molar ratio promotes the retention of arsenic in fly ash and in turn reduces its emission. The reaction between CaO and arsenic is largely dependent on the sulfation of CaO. Leaching of arsenic from fly ash is greatly dependent on the pH value of leachate. Alkali fly ash generates a high pH value solution during leaching test, facilitating the prohibition of arsenic leaching. The mechanism of arsenic leaching in alkali fly ash can be described as that arsenic first releases from fly ash quickly and then subjects to the reaction with calcium to form precipitate under high pH value condition.
- arsenic,
- fluidized bed,
- calcium oxide,
- leaching characteristic

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References(15)

References

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