DOI QR코드

DOI QR Code

$CaSO_4$ Decomposition and Desulfurization in In-Furnace Desulfurization for Oxy-Fuel Combustion Using DTF

DTF를 이용한 순산소연소 조건에서 탈황반응과 $CaSO_4$ 분해 특성

  • Received : 2011.04.06
  • Accepted : 2011.06.26
  • Published : 2011.06.30

Abstract

In general, the decomposition of $CaSO_4$ formed by sulfation reaction in the in-furnace desulfurization process using limestone has strong effect on the desulfurization reaction under the oxy-fuel combustion condition. In this study, the conversion rates were measured and reaction rates were calculated in order to investigate the effects of the experimental variables such as temperature and the concentrations of $CO_2$, $O_2$, $SO_2$, on the $CaSO_4$ decomposition reaction using DTF (Drop Tube Furnace) in the desulfurization reaction. The conversion rate and the reaction rate of $CaSO_4$ decomposition reaction were increased with reaction temperature. $CO_2$ concentration has little effect on $CaSO_4$ decomposition reaction in the presence of $O_2$. Under the same experimental conditions, the decomposition rate of $CaSO_4$ was enhanced with the decreasing the $O_2$ concentration, but vice versa with the increasing of $SO_2$ concentration.

순산소연소 조건하의 로내 탈황공정에서 황화반응 생성물인 $CaSO_4$의 재분해가 탈황반응에 미치는 영향이 크다. 본 연구에서는 DTF (Drop Tube Furnace)를 이용하여 반응온도, $CO_2$, $O_2$, $SO_2$, 농도 등을 포함한 다양한 실험 변수들이 $CaSO_4$ 탈황반응에 미치는 영향을 파악하기 위하여 분해반응의 전환율을 측정하고 반응속도를 계산하였다. 반응온도가 상승함에 따라 $CaSO_4$ 분해반응의 전환율과 반응속도가 증가하였고 $O_2$가 존재하는 조건에서 $CO_2$ 농도의 영향은 크지 않았다. 동일한 조건에서 $CaSO_4$ 분해속도는 $O_2$ 농도가 감소함에 따라 증가하였으나 $SO_2$ 농도가 증가함에 따라 감소되었다.

Keywords

References

  1. An, Y. M., Jo, H. D., Park, Y. S., Keel, S. I. and Lee, H. K., "Study on the In-Furnace Desulfurization for Oxy-Fuel Combustion Flue Gases Using Drop Tube Furnace," Korea Chem. Eng. Res., 47(4), 512-517(2009).
  2. An, Y. M., Jo, H. D., Park, Y. S., Keel, S. I. and Lee, H. K., "Study on Calcination Characteristics of Limestones for In-furnace Desulfurization in Oxy-Fuel Combustion," Korea Soc. Environ. Eng., 31(5), 371-377(2009).
  3. IPCC Fourth Assessment Report(AR4), (2007).
  4. Buhre, B. J. P., Elliott, L. K., Sheng, C. D., Gupta, R. P. and Wall, T. F., "Oxy-fuel combustion technology for coalfired powergeneration," Prog. Energy Combus. Sci., 31(4), 283-307(2005). https://doi.org/10.1016/j.pecs.2005.07.001
  5. Tan, Y., Croiset, E., Douglas, M. A. and Thambimuthu, K. V., "Combustion characteristics of coal in a mixture of oxygen and recycled flue gas," Fuel, 85(4), 507-512(2006). https://doi.org/10.1016/j.fuel.2005.08.010
  6. Molburg, J. C. and Doctor, R. D., "$CO_2$ capture from PC boilers with $O_2$-firing," 18th Annual International Pittsburgh Coal Conference(2001).
  7. Liu, H., Katagiri, S. and Okazaki, K., "Drastic SOx removal and influences of various factors $in_2/O_2$ pulverized coal combustion system," Energy Fuels, 15(2), 403-412(2000).
  8. Liu, H., Katagiri, S. and Okazaki, K., "Decomposition behavior and mechanism of calcium sulfate under the condition of $O_2/CO_2$ pulverized coal combusion," Chem. Eng. Comm., 187, 199-214(2001). https://doi.org/10.1080/00986440108912888
  9. Gutierrez Ortiz, F. J. and Ollero, P., "Flue-Gas Desulfurization in an Advanced in-Duct Desulfurization Process: An Empirical Model from an Experimental Pilot-Plant Study," Ind. Eng. Chem. Res., 42(25), 6625-6637(2003). https://doi.org/10.1021/ie030185t
  10. Fuertes, A. B., Velasco, G., Fuente, E. and Alvarez, T., "Study of the direct sulfation of limestone particles at high $CO_2$ partial pressures," Fuel Proc. Technol., 38, 181-192 (1994). https://doi.org/10.1016/0378-3820(94)90047-7
  11. Fuertes, A. B., Velasco, G., Alvarez, T. and Fernandez, M. J., "Sulfation of dolomite particles at high $CO_2$ partial pressures," Thermochim. Acta, 254, 63-78(1995). https://doi.org/10.1016/0040-6031(94)02067-X
  12. Fuertes, A. B. and Fernandez, M. J., "The effect of metallic salt additives on direct sulfation of calcium carbonate and on decomposition of sulfated samples," Thermochim. Acta, 276, 257-269(1996). https://doi.org/10.1016/0040-6031(95)02735-1
  13. Cheng, J., Zhou, J., Liu, L., Zhou, Z., Huang, Z., Cao, X., Zhao, Z. and Cen, K., "Sulfur removal at high temperature during coal combustion in furnaces: a review," Prog. Energy Combus. Sci., 29(5), 381-405(2003). https://doi.org/10.1016/S0360-1285(03)00030-3
  14. Guilin Hu, "Direct sulfation of limestone," AIChE J, 53, 948-960(2007). https://doi.org/10.1002/aic.11129