On the Study of Coal-Water Fuel Flow Structure during Its Pneumatic-Mechanical Atomization
DOI:
https://doi.org/10.14529/power180401Keywords:
coal-water fuel, suspension, spraying, nozzle, Weber numberAbstract
The paper describes the experimental studies of the structure of coal-water fuel (CWF) flow during its pneumatic spraying in the aerodynamic simulator of the energy boiler furnace. It analyses the 50 % coal and 50 % water CWF spraying mechanism. Parameters: coal particle size was 50 microns or less; temperature was 313 K, 353 K; pressure of CWF was 3 MPa; and pressure of air was 2 MPa. The visualization of CWF torch structure and the assessment of the flow quality were made in the plane perpendicular to the axis of the spray cone in three positions. Geometrical parameters and velocities of CWF droplets during spraying were determined. The change of the We criterion was analyzed depending on CWF drops velocity and their size.
The characteristic zones of CWF spray cone, which are generated during spraying, were established. The ranges of diameters and velocities of CWF droplets corresponding to the core of the flow, the middle and outer zones of the spray cone were determined. The We values were calculated for the corresponding CWF droplets sizes and velocities. The conditions typical for some stages of droplets crushing of sprayed CWF were described.
The research outcomes can be used for the mathematical and physical simulations of CWF spraying in the furnaces of power boilers to estimate the forecast aerodynamic characteristics of the designed and existing units.
References
Franco A., Diaz A.R. The Future Challenges for “Clean Coal Technologies”: Joining Efficiency Increase and Emission Control. Dipartimento d’Energetica “L. Poggi”, Università di Pisa, 2009, vol. 34, iss. 3, pp. 348–354. DOI: 10.1016/j.energy.2008.09.012
Dolgushin I.A. Issledovaniye i sovershenstvovaniye skhemy T·ES s kotlom TSKS dlya povysheniya effek-tivnosti i uluchsheniya ekologicheskikh pokazateley: dis. kand. tekhn. nauk [Research and Improvement of
the Scheme of Thermal Power Plants with a Boiler CCS to Improve Efficiency and Improve Environmental Per-formance. Cand. Sci. Diss.]. Moscow, 2014. 166 p.
Meza C.G., Zuluaga Rodríguez C. et al. Toward a 100 % Renewable Island: A Case Study of Ometepe's Energy Mix. Renewable Energy, 2019, vol. 132, pp. 628–648. DOI: 10.1016/j.renene.2018.07.124
Marinicheva O. [Coal Returns to Generation]. Energetika i promyshlennost' Rossii [Energy and Industry of Russia], 2012, no. 11. (in Russ.)
Khodakov G.S. Coal-Water Suspensions in Power Engineering. Thermal Engineering, 2007, vol. 54, no. 1, pp. 36–47. DOI: 10.1134/S0040601507010077
Salamatin A.G. [On the State and Prospects of Using Coal-Water Fuel in Russia]. Ugol’ [Coal], 2000,
no. 3, pp. 10–15. (in Russ.)
Nyashina G.S., Strizhak P.A. The Influence of Liquid Carbon Dioxide Emissions from the Combustion of Coal-Water Slurries. Environmental Pollution, 2018, vol. 242, pp. 31–41. DOI: 10.1016/j.envpol.2018.06.072
Dolinsky A.A., Khalatov A.A. [Hydrocarbon Fuel: Prospects for Use in Power Engineering and the Housing and Utilities Sector]. Prom. Teplotekhnika [Prom. Heat Engineering], 2007, vol. 29, no. 5, pp. 70–79. (in Russ.)
Maltsev L.I., Kravchenko I.V., Lazarev S.I., Lapin D.A. [Combustion of Coal in the form of a Coal-Water Slurry in Low-Capacity Boilers]. Teploenergetika [Thermal Engineering], 2014, no. 7, pp. 25–29.
DOI: 10.1134 / S0040363614070066. (in Russ.)
Osintsev K.V. [The Organization of the Flaring of Coal-Water Suspensions in the Furnaces of Energy Boilers]. VIII Vserossiyskaya konferentsiya s mezhdunarodnym uchastiyem “Goreniye tverdogo topliva” [VIII All-Russian Conference with International Participation “Solid Fuel Combustion”], 2012, pp. 72.1–72.8. (in Russ.)
Mingaleeva G.R. [Determination of the Optimal Characteristics of Coal-Water Fuel under the Terms
of Transportation and Gasification]. VIII Vserossiyskaya konferentsiya s mezhdunarodnym uchastiyem “Goreniye tverdogo topliva” [VIII All-Russian Conference with International Participation “Solid Fuel Combustion”], 2012, pp. 65.1–65.4. (in Russ.)
Baranova M.P. [Influence of Plasticizing Additives on the Rheological Characteristics of Coal-Water Slur-ries from Coal of Varying Degrees of Metamorphism]. Trudy KGTU [Proc. of KSTU], 2006, no. 2–3,
pp. 143–147. (in Russ.)
Tarabanko V.E., Baranova M.P. [Nature of Stabilization of Coal-Water Fuel Suspensions]. Tekhnich-eskaya khimiya. Ot teorii k praktike: sb. nauch. tr. [Technical Chemistry. From Theory to Practice: Col. of Scien-tific Proc.], Perm, 2008, pp. 299–304. (in Russ.)
Beletsky V.S., Sergeev P.V., Boreyko M.K. [On the Regulation of the Electrokinetic Properties of Coal in Suspensions]. Khimiya tverdogo topliva [Chemistry of Solid Fuels], 1990, no. 5, pp. 73–75. (in Russ.)
Ukigai T. et. al. Coal Slurry. Chem. Lett, 1995, pp. 371–374.
Tolokolnikov A.A., Yankovsky S.A., Gubin V.E., Zenkov A.V., Zaitsev A.S. Research of Mechanical Treatment Influence on Rheological Properties of Coal-Water Fuel Based on Low-Grade 3B Coal. MATEC Web of Conferences, 2016, vol. 91, 01012. DOI: 10.1051/matecconf/20179101012
Gao Z., Zhu S., Zheng M., Wu Z., Lü H., Liu W. Effects of Fractal Surface on Rheological Behavior and Combustion Kinetics of Modified Brown Coal Water Slurries. International Journal of Coal Science and Techno-logy, 2015, vol. 2, iss. 3, pp. 211–222. DOI: 10.1007/s40789-015-0075-0
Senchurova Yu.A., Murko V.I., Fedyayev V.I., Dziuba D.A., Puzyrev E.M. [Research Results of Spraying of Water Coal Fuel by Pneumo-Mechanical Nozzles]. Izvestiya Tomskogo politekhnicheskogo universiteta [News of Tomsk Polytechnic University], 2008, vol. 312, no. 4, pp. 37–40. (in Russ.)
Murko V.I., Fedyaev V.I., Karpenok V.I. et al. [The Results of Studies of the Processes of Spraying and Burning Coal Suspension Fuel]. Sovremennaya nauka [Modern Science], 2012, no. 1 (9), pp. 89–96. (in Russ.)
Senchurova Yu.A., Murko V.I. [The Mechanism of Spraying Water Coal Fuel]. Tekhnologii. Innovatsii: materialy vserossiyskoy nauchnoy konferentsii molodykh uchenykh (8–11 dekabrya 2005 g.): Novosibirskiy gosudarstvennyy tekhnicheskiy universitet [Science. Technology. Innovations: Materials of the All-Russian Scien-tific Conference of Young Scientists (December 8–11, 2005): Novosibirsk State Technical University], 2006, part 3, pp. 84–86. (in Russ.)
Daviault S.G., Ramadan O.B., Matida E.A., Hughes P.M., Hughes R. Atomization of the Twin Fluid
Atomizer. Fuel, 2012, vol. 98, pp. 183–193. DOI: 10.1016/j.fuel.2012.02.042
Ma X., Duan Y., Liu M. Atomization of Petroleum-Coke Sludge Slurry Using Effervescent Atomizer.
Experimental Thermal and Fluid Science, 2013, vol. 46, pp. 131–138. DOI: 10.1016/j.expthermflusci.2012.12.003
Boyko V.M., Poplavsky S.V. [Experimental Study of Two Types of Disruptive Destruction of a Drop in
a Stream Behind a Shock Wave]. Fizika goreniya i vzryva [Physics of Combustion and Explosion], 2012, vol. 48, no. 4, pp. 76–82. (in Russ.)
Jakobs T., Djordjevic N., Fleck S. et al. Gasification of High Viscous Slurry R & D on Atomization and Numerical Simulation. Applied Energy, 2012, vol. 93, pp. 449–456. DOI: 10.1016/j.apenergy.2011.12.026
Smith C.F., Sojka P.E., Thames J.M. Water-Free-Fluid-Resistance Slurry Atomization. Journal of Engi-neering for Gas Turbines and Power, 1990, vol. 112 (1), pp. 15–20. DOI:10.1115/1.2906470
Pilch M., Erdman C.A. Accuracy of the Acceleration-Induced Breakup of Liquid Drop. Int. J. Multiphase Flow, 1987, vol. 13, pp. 741–757. DOI: 10.1016/0301-9322(87)90063-2
Galustov V.S. Pryamotochnyye raspylitel’nyye apparaty v teploenergetike [Direct-Flow Spray Devices in Power System]. Moscow, Energoatomizdat Publ., 1989. 240 p.
