CFD based combustion model for sewage sludge gasification in a fluidized bed
CFD based combustion model for sewage sludge gasification in a fluidized bed
Yiqun WANG, Lifeng YAN()
Hefei National Laboratory for Physcial Sciences at the Microscale and Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
Gasification is one potential way to use sewage sludge as renewable energy and solve the environmental problems caused by the huge amount of sewage sludge. In this paper, a three-dimensional Computational Fluid Dynamics (CFD) model has been developed to simulate the sewage sludge gasification process in a fluidized bed. The model describes the complex physical and chemical phenomena in the gasifier including turbulent flow, heat and mass transfer, and chemical reactions. The model is based on the Eulerian-Lagrangian concept using the non-premixed combustion modeling approach. In terms of the CFD software FLUENT, which represents a powerful tool for gasifier analysis, the simulations provide detailed information on the gas products and temperature distribution in the gasifier. The model sensitivity is analyzed by performing the model in a laboratory-scale fluidized bed in the literature, and the model validation is carried out by comparing with experimental data from the literature. Results show that reasonably good agreement was achieved. Effects of temperature and Equivalence Ratio (ER) on the quality of product syngas (H2 + CO) are also studied.
Corresponding Author(s):
YAN Lifeng,Email:lfyan@ustc.edu.cn
引用本文:
. CFD based combustion model for sewage sludge gasification in a fluidized bed[J]. Frontiers of Chemical Engineering in China, 2009, 3(2): 138-145.
Yiqun WANG, Lifeng YAN. CFD based combustion model for sewage sludge gasification in a fluidized bed. Front Chem Eng Chin, 2009, 3(2): 138-145.
Cui H, Ninomiya Y, Masui M, Mizukoshi H, Sakano T, Kanaoka C. Fundamental Behaviors in Combustion of Raw Sewage Sludge. Energy & Fuels , 2006, 20: 77-83 doi: 10.1021/ef050188d
2
Hartman M, Svoboda K, Pohorely M, Trnka O. Combustion of dried sewage sludge in a fluidized-bed reactor. Ind Eng Chem Res , 2005, 44: 3432-3441 doi: 10.1021/ie040248n
3
Midillia A, Dogrub M, Howarthb C R. Lingc M J, Ayhan T. Combustible gas production from sewage sludge with a downdraft gasifier. Energy Conversion & Management , 2001, 42: 157-172 doi: 10.1016/S0196-8904(00)00053-4
4
Dom?′nguez A, Menéndez J A, Pis J J. Hydrogen rich fuel gas production from the pyrolysis of wet sewage sludge at high temperature. J Anal Appl Pyrolysis , 2006, 77: 127-132 doi: 10.1016/j.jaap.2006.02.003
5
Ferrasse J H, Seyssiecq I, Roche N. Thermal Gasification: A Feasible Solution for Sewage Sludge Valorisation?Chemical Engineering & Technology , 2003, 26: 941-945 doi: 10.1002/ceat.200301813
6
J Manya J, Sanchez J L, Gonzalo A, Arauzo J. Air gasification of dried sewage sludge in a fluidized bed: effect of the operating conditions and in-bed use of alumina. Energy & Fuels , 2005, 19, 629-636 doi: 10.1021/ef0497614
7
Corella J, Toledo J M. Incineration of doped sludges in fluidized bed. Fate and partitioning of six targeted heavy metals. I. Pilot plant used and results. Journal of Hazardous Materials , 2000, B80: 81-105 doi: 10.1016/S0304-3894(00)00280-6
8
Shi S P, Zitney S E, Shahnam M, Syamlal M, Rogers W A. Journal of the Energy Institute, 2006, 79(4): 217-221 doi: 10.1179/174602206X148865
9
Wang S J, Lu J D, Li W J, Hu Z J. Modeling of pulverized coal combustion in cement rotary Kiln.Energy & Fuels , 2006, 20(6): 2350-2356 doi: 10.1021/ef060027p
10
Chen C X, Horio M, Kojima T. Use of numerical modeling in the design and scale-up of entrained flow coal gasifiers. Fuel , 2001, 80(10): 1513-1523 doi: 10.1016/S0016-2361(01)00013-8
11
Vicente W, Ochoa S, Aguillon J, Barrios E. An Eulerian model for the simulation of an entrained flow coal gasifier. Applied Thermal Engineering , 2003, 23(15): 1993-2008 doi: 10.1016/S1359-4311(03)00149-2
12
Fletcher D F, Haynes B S, Christo F C, Joseph S D. A CFD based combustion model of an entrained flow biomass gasifier. Applied Mathematical Modelling , 2000, 24: 165-182 doi: 10.1016/S0307-904X(99)00025-6
13
Grammelis P, Kakaras E. Biomass Combustion Modeling in Fluidized Beds. Energy & Fuels , 2005, 19: 292-297 doi: 10.1021/ef049838o
14
Rostami A A, Hajaligol M R, Wrenn S E. A biomass pyrolysis sub-model for CFD applications. Fuel , 2004, 83: 1519-155 doi: 10.1016/j.fuel.2003.09.024
15
Petersen I, Werther J. Experimental investigation and modeling of gasification of sewage sludge in the circulating fluidized bed. Chemical Engineering Science , 2005, 60(16): 4469-4484 doi: 10.1016/j.ces.2005.02.058
16
Khiari B, Marias F, Zagrouba F, Vaxelaire J. Use of a transient model to simulate fluidized bed incineration of sewage sludge. Journal of Hazardous Materials , 2006, 135(1-3): 200-209 doi: 10.1016/j.jhazmat.2005.11.068
17
Petersen I, Werther J. Experimental investigation and modeling of gasification of sewage sludge in the circulating fluidized bed. Chemical Engineering and Processing , 2005, 44(7): 717-736 doi: 10.1016/j.cep.2004.09.001
18
Zarnescu V, Pisupati S V. An Integrative Approach for Combustor Design Using CFD Methods. Energy & Fuels , 2002, 16: 622-633 doi: 10.1021/ef010189f
19
Dixon T F, Mann A P, Plaza F, Gilfillan W N. Development of advanced technology for biomass combustion—CFD as an essential tool. Fuel , 2005, 84: 1303-1311 doi: 10.1016/j.fuel.2004.09.024
20
Fluent Inc, FLUENT 6.1 User's Guide. 2003
21
Sadakaa S S, Ghalyb A E, Sabbahc M A. Two phase bio-mass air-steam gasification model for fluidized bed reactors:Part I-model development. Biomass and Bioenergy , 2002, 22: 439-462 doi: 10.1016/S0961-9534(02)00023-5
22
Kee R J, Rupley F M, Miller J A. Chemkin-II: A Fortran chemical kinetics package for the analysis of gas-phase chemical kinetics. Technical Report SAND 89-8009 , Sandia National Labs, 1989
23
Filippis P D, Borgianni C, Paolucci M, Pochetti F. Prediction of syngas quality for two-stage gasification of selected waste feedstocks. Waste Management , 2004, 24: 633-639 doi: 10.1016/j.wasman.2004.02.014
24
Corella J, Sanz A. Modeling circulating fluidized bed biomass gasifiers:a pseudo-rigorous model for stationary state. Fuel Processing Technology , 2005, 86(9): 1021-1053 doi: 10.1016/j.fuproc.2004.11.013
