Experimental Study on the Environmental Behaviors of Poisonous Trace Elements in Post-Gasified Residues

Abstract:

Pyrolysis chars at 500°C, 700°C, 900°C and coal combustion ashes were prepared to simulate the three zones residues of underground coal gasification. The contents of trace elements in solid residues, such as chromium, manganese, arsenic, cobalt, nickel and lead, were determined by using inductively coupled plasma mass spectroscopy (ICP-MS) and the enrichment factors were also calculated. By immersing the pyrolysis chars and coal combustion ashes in weakly acidic leaching liquid (pH=4, 5, 6), the leaching features of above trace elements and their potential threat on groundwater were characterized. Compared with the enrichment feature of Fe, the results indicate that CrMnCo stably exist in pyrolysis and combustion process; Ni and As get depleted in low-temperature pyrolysis chars, while enriched in 900°C chars and coal combustion ashes; Pb becomes enriched in ash, but gets depleted with the increase of pyrolysis temperature. The concentration of As in ash leachate is higher than the 5^th class of groundwater quality standard which may cause serious pollution; the concentration of Ni is below the 4^th class and may contaminate the groundwater; other elements in leachate have little influence on groundwater because of low concentrations below the 3^rd class of groundwater quality standard.

• Periodical: Advanced Materials Research (Volumes 805-806)
• Pages: 1478-1483
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.805-806.1478
• Online since: September 2013
• Authors: Bing Xu*, Lun Jian Chen, Bao Lin Xing, Gui Yun Yi, Long Li
• Keywords: Coal Combustion Ashes, Enrichment Factor, Leaching Experiment, Poisonous Trace Elements, Pyrolysis Chars

References

[1] S.J. Wang, et al: Environmental Science & Technology, vol. 33 (2010) No. 10, p.179. (In Chinese).

[2] D.Y. Song, et al: Acta Scientiae Circumstantiae, vol. 25 (2005) No. 9, p.1195. (In Chinese).

[3] C. Fu, X.F. Bai and Y. Jiang: Journal of China Coal Society, vol. 37 (2012) No. 1, p.96. (In Chinese).

[4] E. Sočo and Jan Kalembkiewicz: Fuel, vol. 88 (2009), No. 8, p.1513.

[5] H. Haykiri-Acma, et al: Fuel, vol. 90 (2011) No. 11, p.3447.

[6] Ruud Meij and Henk te Winkel: Atmospheric Environment, vol. 41 (2007) No. 40, p.9262.

[7] R. Świetlik, M. Trojanowska and M.A. Jóźwiak: Fuel Processing Technology, vol. 95 (2012), p.109.

[8] J.G. Li, et al: Journal of China Coal Society, vol. 37 (2012) No. supp. 1, p.173. (In Chinese).

[9] Y.C. Zhang, et al: Journal of China Coal Society, vol. 37 (2012) No. 7, p.1211. (In Chinese).

[10] D.Y. Song, et al: Journal of China University of Mining & Technology, vol. 32 (2003) No. 3, p.316. (In Chinese).

[11] C.G. Zheng: Journal of Tai Yuan University of Technology, vol. 41 (2010) No. 5, p.651. (In Chinese).

[12] Y.Q. Wang, et al: Environmental Science, vol. 17 (1996) No. 1, p.16. (In Chinese).

[13] Seferinoğlu M, et al: Fuel, vol. 82 (2003) No. 14, p.1721.

[14] J. Liang, et al: Acta Scientiae Circumstantiae, vol. 27 (2007) No. 11, p.1858. (In Chinese).

[15] J. Liang, et al: Acta Scientiae Circumstantiae, vol. 26 (2006) No. 3, p.483. (In Chinese).

[16] Kapusta K and Stańczyk K: Fuel, vol. 90 (2011) No. 5, p. (1927).

[17] S.Q. Liu, et al: Journal of China University of Mining & Technology, vol. 17 (2007) No. 4, p.467.

[18] Smoli N Ski A, et al: Water Air Soil Pollut, vol. 223 (2012) No. 9, p.5745.

[19] China Environmental Science Research Institute of Solid Waste Pollution Control Technologies. HJ557-2010[S]. (2010).

[20] J.Y. Zhao, et al: Coal Geology of China, vol. 14 (2002) No. supp. 1, p.5. (In Chinese).

[21] C.Z. Deng, et al: Environmental Chemistry, vol. 31 (2012) No. 9, p.1362. (In Chinese).