Skip to main content
Log in

Effect of Additives to Improve Calcium-Based Sorbents in Semi-Dry Flue Gas Desulphurization

  • Published:
Emission Control Science and Technology Aims and scope Submit manuscript


Semi-dry flue gas desulfurization (FGD) technology is used by some coal-based power plants to remove sulfur dioxide from flue gas. In semi-dry FGD systems, SO2 is removed by calcium-based sorbents in a reactive spray dryer, but the level of desulfurization is lower than in wet FGD systems. This work evaluates the effects of seven additives in the desulfurization of the flue gas: magnesium hydroxide, ammonium nitrate, ammonium acetate, ammonium phosphate, sodium hydroxide, citric acid, and urea. Slurries with calcium hydroxide concentrations of 10 and 20 wt% containing 2 and 4 wt% of an additive were applied in the removal of SO2. Additives containing ammonium intensified the removal of SO2 and increased the yield of the reaction. The SO2 content in the flue gas reduced by 73.8% when applying a slurry containing 4 wt% of ammonium nitrate and 10 wt% of Ca(OH)2. The use of this slurry increased the removal of SO2 by 13.5% when compared to the best result obtained using calcium hydroxide slurry without any additive.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Subscribe and save

Springer+ Basic
EUR 32.99 /Month
  • Get 10 units per month
  • Download Article/Chapter or Ebook
  • 1 Unit = 1 Article or 1 Chapter
  • Cancel anytime
Subscribe now

Buy Now

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8

Similar content being viewed by others


  1. Valle-Zermeno, R., Formosa, J., Chimenos, J.M.: Wet flue gas desulfurization using alkaline agents. Rev. Chem. Eng. 31, 303–327 (2015)

    Google Scholar 

  2. Hill, F.F., Zank, J.: Flue gas desulphurization by spray dry absorption. Chem. Eng. Process. 39, 45–52 (2000)

    Article  Google Scholar 

  3. Katolicky, J., Jicha, M.: Influence of the lime slurry droplet spectrum on the efficiency of semi-dry flue gas desulfurization. Chem. Eng. Technol. 36, 156–166 (2013)

    Article  Google Scholar 

  4. Getler, J.L., Shelton, H.L., Furlong, D.A.: Modeling the spray absorption process for SO2 removal. APCA J. 29, 1270–1274 (1979)

    Google Scholar 

  5. Newton, G.H., Kramlich, J., Payne, R.: Modeling the SO2 slurry droplet reaction. AICHE J. 36, 1865–1872 (1990)

    Article  Google Scholar 

  6. Kinzey, J.R., Kinzey, M.K.: Modeling the gas and liquid-phase resistances in the dry scrubbing process for sulfur-dioxide removal, (1988)

  7. Koech, L., Everson, R., Neomagus, H., Rutto, H.: Dissolution kinetics of sorbents and effect of additives in wet flue gas desulfurization. Rev. Chem. Eng. 30, 553–565 (2014)

    Article  Google Scholar 

  8. Frandsen, J.B., Kiil, S., Johnsson, J.E.: Optimisation of a wet FGD pilot plant using fine limestone and organic acids. Chem. Eng. Sci. 56, 3275–3287 (2001)

    Article  Google Scholar 

  9. Arpagaus, C., Collenberg, A., Rutti, D., Assadpour, E., Jafari, S.M.: Nano spray drying for encapsulation of pharmaceuticals. Int. J. Pharm. 546(1-2), 194–214 (2018)

    Article  Google Scholar 

  10. Arpagaus, C., John, P., Collenberg, A., Rutti, D.: Nanocapsules formation by nano spray drying. In: Jafari, S.M. (ed.) Nanoencapsulation Technologies for the Food and Nutraceutical Industries, pp. 346–401. Elsevier, New York, USA (2017)

    Chapter  Google Scholar 

  11. Song, H., Park, J.: Improvement of SO2 removal by the solubility change of Ca(OH)2 in the spray dryer system. Environ. Technol. 22(9), 1001–1006 (2001)

    Article  Google Scholar 

  12. Haghnegahdar, M.R., Rahimi, A., Hatamipour, M.S.: A rate equation for Ca(OH)2 and CO2 reaction in a spouted bed reactor at low gas concentrations. Chem. Eng. Res. Des. 89, 616–620 (2011)

    Article  Google Scholar 

  13. Chen, B., Laucks, M.L., Davis, E.J.: Carbon dioxide uptake by hydrated lime aerosol particles. Aerosol Sci. Technol. 45, 8765–8769 (2004)

    Google Scholar 

  14. Jarvis, J., Meserole, F., Owens, D., Roothaan, E.: Factors involved in the selection of limestone reagents for use in wet FGD systems. In: EPRI/EPA/DOE SO3 Control Symposium. 8 (1991)

  15. Letterman, R.D.: Calcium carbonate dissolution rate in limestone contactors. US Environmental Protection Agency, Washington, USA (1995)

    Google Scholar 

  16. Rochelle, G.T., King, C.J.: The effect of additives on mass transfer in CaCO3 or CaO slurry scrubbing of SO2 from waste gases. Ind. Eng. Chem. Fundam. 16, 67–75 (1977)

    Article  Google Scholar 

  17. Chang, J.C., Mobley, J.D.: Testing and commercialization of byproduct dibasic acids as buffer additives for limestone flue gas desulfurization systems. J. Air Pollut. Control Assoc. 33, 955–962 (1983)

    Article  Google Scholar 

  18. Stergarsek, A., Gerbec, M., Kocjancic, R., Frkal, P.: Modelling and experimental measurements of limestone dissolution under enhanced wet limestone FGD process conditions. Acta Chim. Slov. 46, 323–333 (1999)

    Google Scholar 

  19. Takashina, T., Honjo, S., Ukawa, N., Iwashita, K.: Effect of ammonium concentration on SO2 absorption in a wet limestone gypsum FGD process. J. Chem. Eng. Japan. 35, 197–204 (2002)

    Article  Google Scholar 

  20. Zhou, Y., Zhu, X., Peng, J., Liu, Y., Zhang, D., Zhang, M.: The effect of hydrogen peroxide solution on SO2 removal in the semidry flue gas desulfurization process. J. Hazard. Mater. 170, 436–442 (2009)

    Article  Google Scholar 

  21. Feng, S., Xiao, L., Ge, Z., Yang, L., Du, X., Wu, H.: Parameters analysis of atomized droplets sprayed evaporation in flue gas flow. Int. J. Heat Mass Transf. 129, 936–952 (2019)

    Article  Google Scholar 

  22. Khatib, J.M., Wright, L., Mangat, P.S.: Mechanical and physical properties of concrete containing FDG waste. Mag. Concr. Res. 68, 550–560 (2016)

    Article  Google Scholar 

  23. Castro, R.P.V., Medeiros, J.L., Araujo, O.Q.F., Cruz, M.A., Ribeiro, G.T., Oliveira, V.R.: Fluidized bed treatment of residues of semi-dry flue gas desulfurization units of coal-fired power plants for conversion of sulfites to sulfates. Energy Convers. Manag. 143, 173–187 (2017)

    Article  Google Scholar 

Download references


The authors would like to thank EDP and Eneva for the funding of this work, through the ANEEL Research and Development Program.

Author information

Authors and Affiliations


Corresponding author

Correspondence to Fabiano A. N. Fernandes.

Ethics declarations

Conflict of Interest

The authors declare no conflict of interest.

Additional information

Publisher’s Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

França, Í.W.L., Cartaxo, S.J.M., Bastos-Neto, M. et al. Effect of Additives to Improve Calcium-Based Sorbents in Semi-Dry Flue Gas Desulphurization. Emiss. Control Sci. Technol. 6, 105–112 (2020).

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: