Wet Flue Gas Desulfurization Using a New O-Element Design Which Replaces the Venturi Scrubber

Authors: P. Lestinsky, D. Jecha, V. Brummer, P. Stehlik

Abstract:

Scrubbing by a liquid spraying is one of the most effective processes used for removal of fine particles and soluble gas pollutants (such as SO2, HCl, HF) from the flue gas. There are many configurations of scrubbers designed to provide contact between the liquid and gas stream for effectively capturing particles or soluble gas pollutants, such as spray plates, packed bed towers, jet scrubbers, cyclones, vortex and venturi scrubbers. The primary function of venturi scrubber is the capture of fine particles as well as HCl, HF or SO2 removal with effect of the flue gas temperature decrease before input to the absorption column. In this paper, sulfur dioxide (SO2) from flue gas was captured using new design replacing venturi scrubber (1st degree of wet scrubbing). The flue gas was prepared by the combustion of the carbon disulfide solution in toluene (1:1 vol.) in the flame in the reactor. Such prepared flue gas with temperature around 150°C was processed in designed laboratory O-element scrubber. Water was used as absorbent liquid. The efficiency of SO2 removal, pressure drop and temperature drop were measured on our experimental device. The dependence of these variables on liquid-gas ratio was observed. The average temperature drop was in the range from 150°C to 40°C. The pressure drop was increased with increasing of a liquid-gas ratio, but no too much as for the common venturi scrubber designs. The efficiency of SO2 removal was up to 70 %. The pressure drop of our new designed wet scrubber is similar to commonly used venturi scrubbers; nevertheless the influence of amount of the liquid on pressure drop is not so significant.

Keywords: Desulphurization, absorption, flue gas, modeling.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1100751

References:

[1] Saarnio K., Frey A., Niemi J.V., Timonen H., Ronkko T., Karjalainen P., Vestenius M., Teinilä K., Pirjola L., Niemela V., Keskinen J., Häyrinen A., Hillamo R. Chemical composition and size of particle in emissions of coal-fired power plant with flue gas desulphurization. J. Aerosol Science 73, 14-26, 2014.
[2] Xiao Y.J., Li C.T., Li S.H., Zeng G.M., Wen Q.B., Guo G.Q., Song J.K. Optimal design of a wet-type desulphurization absorber by the numerical simulation method. Chem. Eng. Research and Design 92, 1257-1266, 2014.
[3] Gutierrez Ortiz F.J., Vidal F., Ollero P., Salvador L., Cortes V., Gimenez A. Pilot-plant technical assessment of wet flue gas desulfurization using limestone. Ind. Eng. Chem. Res. 45, 1466-1477, 2006.
[4] Bandyapadhyay A., Biswas M.N. Prediction of the removal efficiency of a novel two-stage hyrid scrubber for flue gas desulphurization. Chem. Eng. Technol. 29, 130-145, 2006.
[5] Dou B., Pan W., Jin Q., Wang W., Li Y. Prediction of SO2 removal efficiency for wet flue gas desulphurization. Energy Conversion and Management 50, 2547-2553, 2009.
[6] Shimono A., Koda S. Laser-spectrometric measurement of uptake coefficient of SO2 an aqueous surfaces. J. Phys. Chem. 100, 10269- 10276, 1996.
[7] Warych J, Szymanowski M. Model of the wet limestone flue gas desulfurization process for cost optimization. Ind. Eng. Chem. Res. 40, 2597–2605, 2001.
[8] Liu S, Xiao W. Modeling and simulation of a bubbling SO2 absorber with granular limestone slurry and an organic acid additive. Chem. Eng. Technol. 29, 1167–1173, 2006.
[9] Chisholm D., Two-Phase Flow in Pipelines and Heat Exchangers. Longman Higher Education, 1983. ISBN 0711457484.
[10] Hewitt G.F., Shires G.L., Polezhaev Y.V. International Encyclopedia of Heat and Mass Transfer. CRC Press, 1997. ISBN 0849393566.
[11] Fore L.B., Dukler A.E. The distribution of drop size and velocity in gas-liquid annular flow. Int. J. Multiphase Flow 21, 137-149, 1995.
[12] Sewant P., Ishii M., Mori M. Droplet entrainment correlation in vertical upward co-current annular two-phase flow. Nuclear Engineering and Design 238, 1342-1352, 2008.
[13] Ramm V., Absorbcija gazov. Moskva: Chimija, 1966, 654 p.
[14] Gilliland E.R., Sherwood T.K. Diffusion of vapors into air streams. Industrial and Engineering Chemistry 26, 516-523, 1934.
[15] Clift R., Grace J.R., Weber M.E. Bubbles, drops, and particles: normal operation and upset conditions. New York: Academic Press, 1978, 380 p. ISBN 01-217-6950-X.
[16] Gao H., Li C., Zeng G., Zhang W., Shi L., Li S., Zeng Y., Fan X., Wen Q., Shu X. Flue gas desulphurization based on limestonegypsum with a novel wet-type PCF device. Separation and Purification Technology 76, 253-260, 2011.