Study on the In-Furnace Desulfurization for Oxy-Fuel Combustion Flue Gases Using Drop Tube Furnace

Drop Tube Furnace를 이용한 순산소연소 배가스 로내탈황에 관한 연구

  • Received : 2009.03.09
  • Accepted : 2009.07.18
  • Published : 2009.08.31

Abstract

$SO_2$ concentrations in oxy-fuel combustion flue gases increases about three times as high as that of conventional air combustion system owing to the flue gas recirculation for the control of combustion temperature. So the desulfurization reaction is different from that of the conventional air combustion system due to exceptionally high $CO_2$ and $SO_2$ concentration. In this study, drop tube furnace(DTF) system was used to investigate the desulfurization characteristics of limestone in oxy-fuel combustion furnace. The experiments were performed under $O_2/CO_2$ atmosphere to examine the effect of operating variables such as reaction temperatures, Ca/S ratios and inlet $SO_2$ concentrations on the $SO_2$ removal efficiencies. $SO_2$ removal efficiency increased with reaction temperature, Ca/S ratio and inlet $SO_2$ concentration. And the addition of water vapor resulted in about 4~6% of increase in $SO_2$ removal efficiency.

순산소 연소에서 $SO_2$ 농도는 배가스의 재순환으로 인해 기존의 공기연소에 비해 3배 이상 높게 나타나고, $CO_2$ 농도와 $SO_2$ 농도가 높기 때문에 탈황현상이 기존의 공기 연소와는 다르게 나타난다. 본 연구에서는 순산소 연소조건에서 로내탈황 특성을 알아보기 위해 Drop Tube Furnace(DTF)를 이용하여, 반응온도, 유입 $SO_2$ 농도 그리고 Ca/S 비 등의 운전변수에 따른 $SO_2$ 제거효율을 측정하였으며 수분의 영향에 대해서도 알아보았다. 반응온도, 유입 $SO_2$ 농도 그리고 Ca/S 비가 증가함에 따라 $SO_2$ 제거효율은 증가하였고 유입가스 내 수분이 존재할 경우 $SO_2$ 제거효율은 약 4~6% 증가하는 것으로 나타났다.

Keywords

References

  1. Buhre, B. J. P., Elliott, L. K., Sheng, C. D., Gupta, R. P. and Wall, T. F., "Oxy-Fuel Combustion Technology for Coal-fired Power Generation, " Prog. Energy Combust. Sci., 31, 283-307(2005) https://doi.org/10.1016/j.pecs.2005.07.001
  2. Wall, T. F., "Combustion Processes for Carbon Capture," Proc. Combust. Inst., 31, 31-47(2007) https://doi.org/10.1016/j.proci.2006.08.123
  3. Ahn, K.-Y., Lee, S.-M. and Lee, Y.-D., 'Application of Oxyfuel Combustion to Power Generation System,' Proc. SAREK 2006 Winter Annual Conference, 370-375(2006)
  4. Kim, H.-J., Choi, W.-Y., Bae, S.-H. and Shin, H.-D., 'Oxy-fuel and Flue Gas Recirculation Combustion Technology: A Review,' KSMEB, 32(10), 729-753(2008)
  5. Chen, J.-C., Liu, Z.-S. and Huang, J.-S., "Emission Characteristics of Coal Combustion in Different $O_2$/$N_2$, $O_2$/$CO_2$ and O2/RFG Atmosphere," J. Hazard. Mater., 142, 266-271(2007) https://doi.org/10.1016/j.jhazmat.2006.08.021
  6. Liu, H., Zailani, R. and Gibbs, B. M., "Comparisons of Pulverized Coal Combustion in Air and in Mixtures of $O_2$/$CO_2$," Fuel, 84, 833-840(2005) https://doi.org/10.1016/j.fuel.2004.11.018
  7. Andersson, K. and Johnsson, F., "Process Evaluation of an 865 MWe Lignite Fired $O_2$/$CO_2$ Power Plant," Energy Conv. Manag., 47, 3487-3498(2006) https://doi.org/10.1016/j.enconman.2005.10.017
  8. Kim, J.-S., 'Climate Change and $CO_2$ Recovery Technology,' NICE, 25(5), 450-458(2007)
  9. Kim, H. K., Kim, Y. M., Lee, S. M. and Ahn, K. Y., "NO Reduction in 0.03-0.2 MW Oxy-fuel Combustor Using Flue Gas Recirculation Technology," Proc. Combust. Inst., 31, 3377-3384(2007) https://doi.org/10.1016/j.proci.2006.08.083
  10. Simpson, A. P. and Simon, A. J., "Second Law Comparison of Oxy-fuel Combustion and Post-combustion Carbon Dioxide Separation," Energy Conv. Manag., 48(11), 3034-3045(2007) https://doi.org/10.1016/j.enconman.2007.06.047
  11. 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
  12. Yoo, K.-S., Song, B.-H., Kim, S.-D. and Kim, K.-T., 'Toxic Gas Cleaning Technology Sorbents in Waste Incinerators,' J. Korea Solid Wastes Engineering Society, 14(6), 611-622(1997)
  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 Combust. Sci., 29, 381-405(2003) https://doi.org/10.1016/S0360-1285(03)00030-3
  14. Chen, C. and Zhao, C., 'Mechanism of Highly Efficient in-furnace Desulfurization by Limestone Under $O_2$/$CO_2$ Coal Combustion Atmosphere,' Ind. Eng. Chem. Res., 45, 5078-5085(2006) https://doi.org/10.1021/ie060196x
  15. Liu, H., Katagiri, S. and Okazaki, K., "Drastic SOx Removal and Influences of Various Factors in $O_2$/$CO_2$ Pulverized Coal Combustion System," Energy Fuels, 15, 403-412(2000) https://doi.org/10.1021/ef000171p
  16. Ye, Z., Wang, W., Zhong, Q. and Bjerle, I., "High Temperature Desulfurization Using Fine Sorbent Particles Under Boiler Injection Conditions," Fuel, 74, 743-750(1995) https://doi.org/10.1016/0016-2361(94)00011-F
  17. Cho, K.C. and Lee, S.I., 'Desulfurization Characteristics of Domestic Limestone, ' J. Korean Society of Environmental Administration, 9(2), 257-264(2003)
  18. Han, K.H., Ryu, H.J., Shun, D.W., Yi, C.K., Ryu, J.I. and Jin, G.T., 'Desulfurization Characteristics of Domestic Anthracite in a Pressurized Fluidized Bed Combustor,' 24th KOSCO Symposium Symposium, 237-246(2002)
  19. Han, K.H., Song, Y.S., Ryu, J.I., Son, J.E. and Jin, G.T., 'The Characteristics of $SO_2$ Emission with Korean Anthracite in a Pressurized Fluidized Bed Combustor,' HWAHAK KONGHAK, 41(1), 86-92(2003)
  20. Hu, G., Dam-Johansen, K., Wedel, S. and Hansen, J. P., "Direct Sulfation of Limestone," AIChE J., 53(4), 948-960(2007) https://doi.org/10.1002/aic.11129
  21. Hu, G., Dam-Johansen, K., Wedel, S. and Peter Hansen, J., "Review of the Direct Sulfation of Limestone, " Prog. Energy Combust. Sci., 32, 386-407(2006) https://doi.org/10.1016/j.pecs.2006.03.001
  22. Jin, D.S., Deshwal, Park, B.R., Park, Y.S. and Lee, H.K., "Simultaneous Removal of $SO_2$ and NO by Wet Scrubbing Using Aqueous Chlorine-dioxide Solution," J. Hazard. Mater., 135, 412-417(2006) https://doi.org/10.1016/j.jhazmat.2005.12.001