MODELING OF A DUSTED GAS FLOW CLEANING PROCESS USING A KINEMATIC MODEL OF THE INTERACTION OF DISPERSED PARTICLES WITH DROPLETS IN A WET SCRUBBER

Keywords: dusted flow cleaning, slurry droplets, wet scrubber, Venturi tube, spray density

Abstract

A mathematical model is proposed for the scavenging process of the dispersed particles by droplets in a wet scrubber under excess spray density in Venturi tube within kinematic approach of the interaction of particles in countercurrent gas-dispersed flows, which refines the existing engineering model, taking into account the spatial size variation of the droplets, due to their coagulation with wet slurry droplets and uncaptured particles entering a wet scrubber from the Venturi tube. The results of calculations with the adopted mathematical model showed that in case of possibility to organize the spraying of a gas flow in a scrubber with 300–500 micron droplets aerosol at a specific spray density of about 1 liter/m3, a 1–2 meters wide layer of droplets ensures effective absorption of both uncaptured PM2.5 solid particles, and the slurry droplets from the Venturi tube. The ejection of the slurry droplets into a wet scrubber from the Venturi tube, and the associated increase in the size of the scrubber droplets due to coagulation with slurry droplets, does not noticeably affect the efficiency of the dusted gas stream cleaning. An adopted mathematical model was applied to calculate the capture of particles by droplets in cylindrical and conical scrubbers. Due to the increase in a residence time of the droplets upon increased velocity of the countercurrent gas flow, the efficiency of gas cleaning from dispersed particles in a conical scrubber appears to be higher than in a cylindrical scrubber. However, with an increase in the spray density above 2 liter/m3 and with droplet diameters greater than 1000 microns, the efficiency of the conical scrubber decreases, which is associated to an increase in the escape of a significant proportion of massive drops to the walls with a reduction in the scrubber reactor cross-section.  Bibl. 21, Fig. 4.

Author Biographies

I.A. Volchyn, Coal Energy Technology Institute of National Academy of Sciences of Ukraine, Kyiv

Doctor of Technical Sciences

V.A. Raschepkin, Coal Energy Technology Institute of National Academy of Sciences of Ukraine, Kyiv

Doctor of Philosophy (Engineering)

References

Commission Implementing Decision (EU) 2017/1442 of 31 July 2017 establishing the best available methods (BAT) for the European Parliament. Official Journal of the European Union. L 212/1. 17.8.2017.

Thierry Lecomte, José Félix Ferrería de la Fuente, Frederik Neuwahl, Michele Canova, Antoine Pinasseau, Ivan Jankov, Thomas Brinkmann, Serge Roudier, Luis Delgado Sancho. Best Available Techniques (BAT) Reference Document for Large Combustion Plants. — Seville, Spain. European IPPC Bureau. 2017. 986 p. — https://eippcb.jrc.ec.europa.eu/sites/default/files/2019-11/JRC_107769_LCPBref_2017.pdf

Directive 2010/75/EU of the European Parliament and of the Council of 24 November 2010 on indutrial emissions (integrated pollution prevention and control). Official Journal of the European Union. L 334. 17.12.2010.

Directive 2015/2193/EU of the European Parliament and of the Council of 25 November 2015 on the limitation of emissions of certain pollutants into the air from medium combustion plants. Official Journal of the European Union. L 313. 28.11.2015. – https://eur-lex.europa.eu/legal-content/EN/TXT/PDF /?uri=CELEX:32015L2193&from=EN

Mussatti D., Pechan E.H. & Associates, Inc. Wet Scrubbers for Particulate Matter. EPA/452/B-02-001. July, 15, 2002. 64 p.

Kropp A.I., Akbrut L.I. [Ash precipitators with Venturi tubes at thermal power plants]. Moscow : Energia, 1977. 460 p. (Rus.)

Volchyn I.A., Raschepkin V.A. [Specific issues of Flue Gas Cleaning in Wet Venturi scrubbers at excess spraying]. Energotehnologii i Resursosberezhenie. [Energy Technologies and Resource Saving]. 2018. No. 3. pp. 41–50. (Rus.)

Volchyn, V. Raschepkin, A. Iasynetskyi A. Flue Gas Dedusting in Venturi Scrubbers at Thermal Power Plants. Environmental Engineering and Management Journal. 2018. 17 (11). pp. 2515–2525.

Shvydkiy V.S., Ladygichev M.G. [Gas Cleaning: A Reference Book]. Moscow : Teploenergetik, 2002. 640 p. (Rus.)

Ravi G., Gupta S.K., Viswanathan S., Ray M.B. Optimization of Venturi Scrubbers Using Genetic Algorithm. Ind. Eng. Chem. Res. 2002. Vol. 41. pp.2988–3002.

Costa M.A., Ribeiro A.P., Tognetti E.R., Aguiar M.L., Goncalves J.A.S., Coury J.R. Performance of a Venturi Scrubber in the Removal of Fine Powder from a Confined Gas Stream. Materials Research. 2005. 8 (2). pp.177–179.

Nabil Rafidi, Fredrik Brogaard, Lei Chen, Rikard Hâkansson, Ali Tabikh. CFD and experimental studies on capture of fine particles by liquid droplets in open spray towers. Sustainable Environment Research. 2018. No. 28. pp 382–388.

Jinder Jow. Resource Utilization and Management of Fly Ash. Cornerstone. The official journal of the World Coal Industry. 2016. Vol. 4, Iss. 3. рр. 61–66.

Brogren C., Karlsson H.T. Modeling the absorption of SO2 in a spray scrubber using the penetration theory. Chem. Eng. Sci. 1997. 52 (18). pp. 3085–3099.

Flagan R.C., Seinfeld J.H. Fundamentals of Air Pollution Engineering. — California Institute of Technology. PRENTICE HALL, 1988. 542 р.

Belousov V.V. [Theoretical bases of gas cleaning processes]. Moscow : Metallurgy, 1988. 256 p. (Rus.)

Volchyn I.A., Raschepkin V.A. [Mathematical modeling of the processes of fly ash particles coagulation with droplets in the Venturi tubes of TPP wet scrubbers]. Energotehnologii i Resursosberezhenie. [Energy Technologies and Resource Saving]. 2012. No. 2. pp. 44–53. (Rus.)

Rudnick S.N., M. Koehler J.L., Martin K.P., Leith D., Cooper D.W. Particle Collection Efficiency in a Venturi Scrubber: Comparison of Experiments with Theory. Environ. Sci. Technol. 1986. 20 (3). рр. 237–242.

Calvert S., Lundgren D., Metha D.S. Venturi Scrubber Modelling. J. Air Pollut. Control Assoc. 1972. Vol. 22. pp. 529–532.

Nigmatulin R.I. [Dynamics of multiphase media]. Moscow : Nauka, 1987. Vol. 1. 464 p. (Rus.)

Raschepkin V., Volchyn I. Simulation of the particulate matter removal process in a wet scrubber with a conical bottom at the excess liquid-to-gas ratios in the Venturi tube. Abstracts: 6th International Congress “Sustainable Development: Protecting the Environment. Energy Saving. Balanced Nature Management». Lviv, September 23–25, 2020. Lviv: Western Ukrainian Consulting Center (ZUKC), Ltd., 2020. P. 23.

Published
2021-09-20
How to Cite
Volchyn, I., & Raschepkin, V. (2021). MODELING OF A DUSTED GAS FLOW CLEANING PROCESS USING A KINEMATIC MODEL OF THE INTERACTION OF DISPERSED PARTICLES WITH DROPLETS IN A WET SCRUBBER. Energy Technologies & Resource Saving, (3), 84-98. https://doi.org/10.33070/etars.3.2021.07
Section
Environment protection