|
Article information
2020 , Volume 25, ¹ 2, p.22-35
Donskoy I.G.
Mathematical modelling of the agglomeration in a reactive porous medium with variable permeability
Thermal processing of waste is usually carried out in fixed-bed reactors. Complex thermochemical behavior of individual components can lead to a decrease in technical and environmental efficiency. One of the problems is the bed agglomeration and formation of zones with decreasing permeability. The paper proposes a method of numerical simulation of porous media with physicochemical processes, which change permeability. Initial formulation proposes this process to be considered as melting of distributed particles in a stochastic media. The melting rate is controlled by heating of the selected element, and its local permeability changes during a phase transition. To solve this problem, numerical algorithm is developed on the basis of splitting methods. This algorithm was used to find a solution for system of non-stationary partial differential equations in two-dimensional case. The data on multiple calculations for different configurations are averaged to compare modelling results. The simulation results show that increasing the fraction of particles of the melting component leads to the significant change of the dynamic and stationary filtration regimes. The reduction in stationary flow rate is exponential function of the fraction of the melting particles. The dynamics of gas flow is also sensitive to the melting particles fraction, within the range of 5–10 % there is a rather sharp transition from a gradual (almost linear) decrease of flow in time to a sharp one, which is close to exponential behaviour. The resulting calculations for the critical fraction are compared with the measured data published for the case of combustion of mixtures with sintering fuel particles (polymers). Further work will address the modification of the model to describe waste incineration, namely, taking into account the pyrolysis and oxidation processes, three-dimensional formulation, etc.
[full text]
Keywords: biomass, solid fuel, single particle, fixed bed, pyrolysis, transfer processes, agglomeration, clinckering
doi: 10.25743/ICT.2020.25.2.003
Author(s):
Donskoy Igor Gennadyevich
PhD.
Position: Senior Research Scientist
Office: Melentiev Institute of Energy Systems SB RAS
Address: 664033, Russia, Irkutsk, 130 Lermontova st.
Phone Office: (3952)500-646
E-mail: donskoy.chem@mail.ru
SPIN-code: 9616-0926 References:
[1]. Ong Z., Cheng Y., Maneerung T., Yao Z., Tong Y.W., Wang C.-H., Dai Y. Co-gasification of woody biomass and sewage sludge in a fixed-bed downdraft gasifier. American Institute of Chemical Engineers Journal. 2015; 61(8):2508–2521. DOI:10.1002/aic.14836
[2]. Madadian E. Experimental observation on downdraft gasification for different biomass feedstocks. Gasification for Low-Grade Feedstock. InTech, 2018:79–93. DOI:10.5772/intechopen.77119
[3]. Tsvetkov M.V., Zyukin I.V., Freiman V.M., Salganskaya M.V., Tsvetkova Y.Y. Possible ways to
prevent ash slagging in peat gasification in the filtration combustion mode. Russian Journal of Applied Chemistry. 2017; 90(10):1706–1711. DOI:10.1134/S1070427217100226
[4]. Siddiqui H., Thengane S.K., Sharma S., Mahajani S.M. Revamping downdraft gasifier to minimize clinker formation for high-ash garden waste as feedstock. Bioresource Technology. 2018; (266): 220–231. DOI:10.1016/j.biortech.2018.06.086
[5]. Bhoi P.R., Huhnke R.L., Kumar A., Indrawan N., Thapa S. Co-gasification of municipal solid waste and biomass in a commercial scale downdraft gasifier. Energy. 2018; (163):513–518. DOI:10.1016/j.energy.2018.08.151
[6]. Allesina G., Pedrazzi S., Tartarini P. Modeling and investigation of the chanelling phenomenon in downdraft stratified gasifiers. Bioresource Technology. 2013; (146):704–712. DOI:10.1016/j.biortech.2013.07.132
[7]. Yang Y.B., Swithenbank J. Mathematical modelling of particle mixing effect on the combustion of municipal solid wastes in a packed-bed furnace. Waste Management. 2008; (28):1290–1300. DOI:10.1016/j.wasman.2007.04.012
[8]. Lutsenko N.A. Numerical model of two-dimensional heterogeneous combustion in porous media under natural convection or forced filtration. Combustion Theory and Modelling. 2018; 22(2):359–377. DOI:10.1080/13647830.2017.1406617
[9]. Levin V.A., Lutsenko N.A. Numerical modeling of two-dimensional time-dependent gas flow through porous heat-evolutional elements. Computational Technologies. 2006; 11(6):44–58. (In Russ.)
[10]. Openyshev P.V., Sheremet M.A. Influence of a porous insert on the fluid flow inside the gasifier shaft. Key Engineering Materials. 2016; (685):235–239. DOI:10.4028/www.scientific.net/KEM.685.235
[11]. Lutsenko N.A., Fetsov S.S. Numerical model of time-dependent gas flows through bed of granular phase change material. Intern. J. of Comput. Methods. 2019; 16(3):1950010. DOI:10.1142/S0219876219500105
[12]. Teplitskii Yu.S., Kovenskii V.I. Statement of boundary and conjugation conditions for problems of heat transfer in granular beds on the basis of a two-temperature model. J. of Engineering Physics and Thermophysics. 2006; 79(6):1147–1156. DOI:10.1007/s10891-006-0217-8
[13]. Hirschfelder J.O., Curtiss, C.F., Bird, R.B. Molecular theory of gases and liquids. New York: Wiley; 1954.
[14]. Kovenskii V.I., Teplitskii Yu.S. On the thermal conductivity of a blown granular bed. J. of Engineering Physics and Thermophysics. 2008; 81(5):998–1005. DOI:10.1007/s10891-009-0113-0
[15]. Zarodnyuk M.S., Svishchev D.A., Donskoy I.G., Zarodnyuk T.S. Formulation of the optimal control problem for gasifier unit. Proc. of XI Intern. Conf. on Non-equilibrium Processes in Nozzles and Jets (NPNJ’2016), 25–31 May 2016, Alushta. Moscow: MAI; 2016:515–516. (In Russ.)
[16]. Misyura S.Y., Donskoy I.G. Dissociation of natural and artificial gas hydrate. Chemical Engineering Science. 2016; (148):65–77. DOI:10.1016/j.ces.2016.03.021
[17]. Aerov M.E, Todes O.M., Narinskii D.A. Apparaty so statsionarnym zernistym sloem: Gidravlicheskie i teplovye osnovy raboty [Stationary granular beds: hydraulics and heat transfer]. Leningrad: Chimiya; 1979: 176. (In Russ.)
[18]. Naraghi M.E., Javadpour F. A stochastic permeability model for the shale-gas systems. International Journal of Coal Geology. 2015; (140):111–124. DOI:10.1016/j.coal.2015.02.004
[19]. Ibrahima F., Tchelepi H.A., Meyer D.W. An efficient distribution method for nonlinear two-phase flow in highly heterogeneous multidimensional stochastic porous media. Computational Geosciences. 2018; 22(1):389–412. DOI:10.1007/s10596-017-9698-0
[20]. Zhou C., Zhang Q., Arnold L., Yang W., Blasiak W. A study of the pyrolysis behaviors of pelletized recovered municipal solid waste fuels. Applied Energy. 2013; 107):173–182. DOI:10.1016/j.apenergy.2013.02.029
[21]. Patankar S.V. Numerical heat transfer and fluid flow. McGraw-Hill, Hemisphere Publishing Corporation; 1980: 197.
[22]. Di Blasi C. Mechanisms of two-dimensional smoldering propagation through packed fuel bed. Combustion Science and Technology. 1995; 106(1-3):103–124. DOI:10.1080/00102209508907769
[23]. Donskoy I.G. Mathematical modelling of woody particles pyrolysis in a fixed bed. Computational Technologies. 2018; 23(6):14–24. (In Russ.) DOI:10.25743/ICT.2018.23.6.003
[24]. Strang G. On the construction and comparison of difference schemes. SIAM J. Numer. Anal. 1968; 5(3):506–517. DOI:10.1137/0705041
[25]. Marchuk G.I. Splitting-up methods for non-stationary problems. Computational Mathematics and Mathematical Physics. 1995; 35(6):667—671.
[26]. Ren Z., Xu C., Lu T., Singer M.A. Dynamic adaptive chemistry with operator splitting schemes for reactive flow simulations. J. of Computational Physics. 2014; (263):19–36. DOI:10.1016/j.jcp.2014.01.016
[27]. Aldushin A.P., Ivleva T.P. Simulation of the hydrodynamic instability of a filtration combustion wave in a porous medium. Combustion, Explosion, and Shock Waves. 2015; 51(1):107–115. DOI:10.1134/S0010508215010116
[28]. Grinchuk P.S. Combustion of heterogeneous systems with a stochastic spatial structure near the propagation limits. Journal of Engineering Physics and Thermophysics. 2013; 86(4):875–887. DOI:10.1007/s10891-013-0907-y
[29]. Duffy N.T.M., Eaton J.A. Investigation of factors affecting channelling in fixed-bed solid fuel combustion using CFD. Combustion and Flame. 2013; 160(10):2204–2220. DOI:10.1016/j.combustflame.2013.04.015
[30]. Castaldi M., van Deventer J., Lavoie J.M., Legrand J., Nzihou A., Pontikes Y., Py X., Vandecasteele C., Vasuedevan P.T. Progress and prospects in the field of biomass and waste to energy and addedvalue materials. Waste and Biomass Valorization. 2017; 8(6):1875–1884. DOI:10.1007/s12649-017-0049-0
[31]. Xin J. Front propagation in heterogeneous media. SIAM Review. 2000; 42(2):161–230. DOI:10.1137/S0036144599364296
[32]. Garcia-Bacaioca P., Mastral J.F., Ceamanos J., Berrueco C., Serrano S. Gasification of biomass/high density polyethylene mixtures in a downdraft gasifier. Bioresource Technology. 2008; (99):5485–5491. DOI:10.1016/j.biortech.2007.11.003
[33]. Ouadi M., Brammer J.G., Kay M., Hornung A. Fixed bed downdraft gasification of paper industry wastes. Applied Energy. 2013; (103):692–699. DOI:10.1016/j.apenergy.2012.10.038
[34]. Salganskaya M.V., Glazov S.V., Salganskii E.A., Zholudev A.F. Filtration combustion of charcoalpolyethylene systems. Russian Journal of Physical Chemistry B. 2010; 4(6):928–933. DOI:10.1134/S1990793110060096
[35]. Salganskaya M.V., Glazov S.V., Salganskiy E.A., Zholudev A.F., Stesik L.N. Filtrational combustion of systems with polymeric materials. Khimicheskaya Fizika. 2013; 32(3):57–61. (In Russ.)
Bibliography link:
Donskoy I.G. Mathematical modelling of the agglomeration in a reactive porous medium with variable permeability // Computational technologies. 2020. V. 25. ¹ 2. P. 22-35
|
