Three-dimensional full-loop simulation of biomass gasification in dual fluidized bed

doi:10.11949/0438-1157.20190192

Abstract

Abstract:

A three-dimensional full-loop simulation of biomass gasification in an industry-scale dual fluidized bed is conducted based on the MP-PIC (multi-phase particle-in-cell) method. In this method, the parcel motion is descript under Lagrangian framework while the gas turbulence is solved by large-eddy simulation (LES), meanwhile, the complex gas-solid interaction, pyrolysis, gasification and homogeneous/heterogeneous reactions are considered simultaneously. Firstly, the independence of grids and particles per parcel (PPP) is conducted, and the numerical results agree well with the experimental data. Secondly, the gas-solid flow characteristics and syngas distributions in dual fluidized bed are revealed and the effects of bed temperature, biomass particle number and drag force correlation on syngas production are analyzed. The results show that the temperature increases, the CO mole fraction at the outlet increases, and the remaining components decrease; the gasification effect of the smaller biomass particle size is better than the larger biomass particle size. The drag model has a negligible effect on the syngas production.

Key words: MP-PIC, dual fluidized bed, biomass gasification, numerical simulation

摘要：

基于多相质点网格方法（multi-phase particle-in-cell，MP-PIC）对工业尺度的双流化床生物质气化过程进行了三维全循环数值模拟。其中，在拉格朗日框架下求解颗粒团运动，采用大涡模拟法（large-eddy simulation, LES）求解气相湍流，同时考虑复杂的气固耦合以及生物质的热解、气化、均相/异相反应。首先，通过独立性检验确定了计算所需的最佳网格数与计算颗粒数，且模拟结果和实验结果对比良好。其次，揭示了流化床内生物质气化过程中的气固流动特性及气体组分分布规律，研究了床内温度、生物质粒径、曳力模型等因素对产物气体组分分布的影响。结果表明：温度升高，出口处的CO摩尔分数增加，而其余组分都减小；较小生物质粒径的气化效果要优于较大的生物质颗粒粒径；曳力模型对各产物气体组分的摩尔分数几乎无影响。

关键词: MP-PIC, 双流化床, 生物质气化, 数值模拟

CLC Number:

Dali KONG, Kun LUO, Junjie LIN, Shuai WANG, Chenshu HU, Debo LI, Jianren FAN. Three-dimensional full-loop simulation of biomass gasification in dual fluidized bed[J]. CIESC Journal, 2019, 70(8): 3167-3176.

孔大力, 罗坤, 林俊杰, 王帅, 胡陈枢, 李德波, 樊建人. 双流化床生物质气化的三维全循环数值模拟[J]. 化工学报, 2019, 70(8): 3167-3176.

Figures/Tables 13

Table 1 Proximate analysis and ultimate analysis of biomass

Proximate analysis/%(mass)				Ultimate analysis/%(mass)
Fixed carbon	Volatile	Ash	Moisture	C	H	O	N, S, Cl
20.2	72.53	2.09	5.18	51.3	5.29	40.9	0.71

Table 2 Chemical reaction and reaction rates

方程	反应速率
$C + O 2 ? C O 2$	$r 2 = 4.34 × 107 θ s T p e x p (- 13590 / T p) [O 2]$
$C + H 2 O ? C O + H 2$	$r 3 f = 6.36 m c T p e x p (- 22645 / T p) [H 2 O]$
$C + H 2 O ? C O + H 2$	$r 3 r = 5.218 × 10 - 4 m c T p 2 e x p (- 6319 / T p - 17.29) [H 2] [C O]$
$C + C O 2 ? 2 C O$	$r 4 f = 6.36 m c T p e x p (- 22645 / T p) [C O 2]$
$C + C O 2 ? 2 C O$	$r 4 r = 5.218 × 10 - 4 m c T p 2 e x p (- 2363 / T p - 20.92) [C O] 2$
$C + 2 H 2 ? C H 4$	$r 5 f = 6.838 × 10 - 3 m c T p e x p (- 8078 / T p - 7.087) [H 2]$
$C + 2 H 2 ? C H 4$	$r 5 r = 0.755 m c T p 0.5 e x p (- 13578 / T p - 0.372) [C H 4] 0.5$
$C O + 0.5 O 2 ? C O 2$	$r 6 = 1.3 × 1011 e x p (- 15155 / T g) [C O] [O 2] 0.5$
$H 2 + 0.5 O 2 ? H 2 O$	$r 7 = 2.2 × 109 e x p (- 13110 / T g) [H 2] [O 2]$
$C H 4 + 2 O 2 ? C O 2 + 2 H 2 O$	$r 8 = 5.01 × 1011 e x p (- 24117 / T g) [C H 4] 0.7 [O 2] 0.8$
$C 2 H 4 + 3 O 2 ? 2 C O 2 + 2 H 2 O$	$r 9 = 1 × 1015 e x p (- 20808 / T g) [C 2 H 4] [O 2]$
$C 3 H 8 + 5 O 2 ? 3 C O 2 + 4 H 2 O$	$r 10 = 8.6 × 1011 e x p (- 15000 / T g) [C 3 H 8] 0.1 [O 2] 1.65$
$C O + H 2 O ? C O 2 + H 2$	$r 11 = 2.75 θ s e x p (- 10079 / T g) [C O] [H 2 O]$

Table 2 Chemical reaction and reaction rates

方程	反应速率
$C + O 2 ? C O 2$	$r 2 = 4.34 × 107 θ s T p e x p (- 13590 / T p) [O 2]$
$C + H 2 O ? C O + H 2$	$r 3 f = 6.36 m c T p e x p (- 22645 / T p) [H 2 O]$
$C + H 2 O ? C O + H 2$	$r 3 r = 5.218 × 10 - 4 m c T p 2 e x p (- 6319 / T p - 17.29) [H 2] [C O]$
$C + C O 2 ? 2 C O$	$r 4 f = 6.36 m c T p e x p (- 22645 / T p) [C O 2]$
$C + C O 2 ? 2 C O$	$r 4 r = 5.218 × 10 - 4 m c T p 2 e x p (- 2363 / T p - 20.92) [C O] 2$
$C + 2 H 2 ? C H 4$	$r 5 f = 6.838 × 10 - 3 m c T p e x p (- 8078 / T p - 7.087) [H 2]$
$C + 2 H 2 ? C H 4$	$r 5 r = 0.755 m c T p 0.5 e x p (- 13578 / T p - 0.372) [C H 4] 0.5$
$C O + 0.5 O 2 ? C O 2$	$r 6 = 1.3 × 1011 e x p (- 15155 / T g) [C O] [O 2] 0.5$
$H 2 + 0.5 O 2 ? H 2 O$	$r 7 = 2.2 × 109 e x p (- 13110 / T g) [H 2] [O 2]$
$C H 4 + 2 O 2 ? C O 2 + 2 H 2 O$	$r 8 = 5.01 × 1011 e x p (- 24117 / T g) [C H 4] 0.7 [O 2] 0.8$
$C 2 H 4 + 3 O 2 ? 2 C O 2 + 2 H 2 O$	$r 9 = 1 × 1015 e x p (- 20808 / T g) [C 2 H 4] [O 2]$
$C 3 H 8 + 5 O 2 ? 3 C O 2 + 4 H 2 O$	$r 10 = 8.6 × 1011 e x p (- 15000 / T g) [C 3 H 8] 0.1 [O 2] 1.65$
$C O + H 2 O ? C O 2 + H 2$	$r 11 = 2.75 θ s e x p (- 10079 / T g) [C O] [H 2 O]$

Fig.1 Geometry and grids of dual fluidized bed

Table 3 Operational parameters

参数	数值	参数	数值
进料量/(kg/h)	72.8	二次风量/(kg/h)	260
进料温度/K	293	二次风温度/K	632
气化室蒸汽质量流量/(kg/h)	85.6	三次风量/(kg/h)	362
气化室蒸汽温度/K	640	三次风温度/K	648
拨料蒸汽流量/(kg/h)	27.1	甲烷流量/(kg/h)	19.5
拨料蒸汽温度/K	640	甲烷温度/K	293
一次风量/(kg/h)	36	助燃空气流量/(kg/h)	561
一次风温度/K	602	助燃空气温度/K	293

Fig.2 Time-evolution solid flux under different grids number and particles number

Table 4 Average solid flux under different parameters

算例	网格数	平均颗粒流量/(kg/s)	算例	计算颗粒数	平均颗粒流量/(kg/s)
Case 1	223125	6.43	Case 4	347705	6.30
Case 2	286875	6.50	Case 5	474369	6.38
Case 3	354375	6.85	Case 6	539796	7.09

Fig.3 Molar fraction of export product gases

Fig.4 Comparison of gaseous mole fraction at outlet between experiment and simulation

Fig.5 Time evolution of gas-solid flow patterns in dual fluidized bed

Fig.6 Contour plots of syngas mass fraction in dual fluidized bed

Fig.7 Distribution of gas and particle temperature in dual fluidized bed

Fig.8 Pressure distribution in the dual fluidized bed

Fig.9 Effects of operating conditions on gaseous mole fraction in dual fluidized bed

References 32

1	Ellabban O , Abu-Rub H , Blaabjerg F . Renewable energy resources: current status, future prospects and their enabling technology[J]. Renewable and Sustainable Energy Reviews, 2014, 39: 748-764.
2	Ong Z , Cheng Y , Maneerung T , et al . Co‐gasification of woody biomass and sewage sludge in a fixed‐bed downdraft gasifier[J]. AIChE Journal, 2015, 61(8): 2508-2521.
3	Heidenreich S , Foscolo P U . New concepts in biomass gasification[J]. Progress in Energy and Combustion Science, 2015, 46: 72-95.
4	Shayan E , Zare V , Mirzaee I . Hydrogen production from biomass gasification: a theoretical comparison of using different gasification agents[J]. Energy Conversion and Management, 2018, 159: 30-41.
5	常圣强, 李望良, 张晓宇, 等 . 生物质气化发电技术研究进展[J]. 化工学报, 2018, 69(8): 27-39.
	Chang S Q , Li W L , Zhang X Y , et al . Progress in biomass gasification power generation technology [J]. CIESC Journal, 2018, 69(8): 27-39.
6	Gómez-Barea A , Leckner B . Modeling of biomass gasification in fluidized bed[J]. Progress in Energy and Combustion Science, 2010, 36(4): 444-509.
7	Karl J , Pröll T . Steam gasification of biomass in dual fluidized bed gasifiers: a review[J]. Renewable and Sustainable Energy Reviews, 2018, 98: 64-78.
8	Zhong W , Yu A , Zhou G , et al . CFD simulation of dense particulate reaction system: approaches, recent advances and applications[J]. Chemical Engineering Science, 2016, 140: 16-43.
9	van der Hoef M A , van Sint Annaland M , Deen N G , et al . Numerical simulation of dense gas-solid fluidized beds: a multiscale modeling strategy[J]. Annu. Rev. Fluid Mech., 2008, 40: 47-70.
10	Baltussen M W , Buist K A , Peters E A , et al . Multiscale modelling of dense gas–particle flows[J]. Advances in Chemical Engineering, 2018, 53: 1-52.
11	Snider D M . An incompressible three-dimensional multiphase particle-in-cell model for dense particle flows[J]. Journal of Computational Physics, 2001, 170(2): 523-549.
12	Xie J , Zhong W , Jin B , et al . Simulation on gasification of forestry residues in fluidized beds by Eulerian-Lagrangian approach[J]. Bioresource Technology, 2012, 121: 36-46.
13	Xie J , Zhong W , Jin B . LES‐Lagrangian modelling on gasification of combustible solid waste in a spouted bed[J]. The Canadian Journal of Chemical Engineering, 2014, 92(7): 1325-1333.
14	Loha C , Chattopadhyay H , Chatterjee P K . Three dimensional kinetic modeling of fluidized bed biomass gasification[J]. Chemical Engineering Science, 2014, 109: 53-64.
15	Wang S , Luo K , Hu C , et al . Impact of operating parameters on biomass gasification in a fluidized bed reactor: an Eulerian-Lagrangian approach[J]. Powder Technology, 2018, 333: 304-316.
16	Shuai W , Huang L , Zhenhua H , et al . Numerical modeling of a bubbling fluidized bed coal gasifier by kinetic theory of rough spheres[J]. Fuel, 2014, 130: 197-202.
17	Wang S , Yin W , Li Z , et al . Numerical investigation of chemical looping gasification process using solid fuels for syngas production[J]. Energy Conversion and Management, 2018, 173: 296-302.
18	Xie J , Zhong W , Shao Y , et al . Simulation of combustion of municipal solid waste and coal in an industrial-scale circulating fluidized bed boiler[J]. Energy & Fuels, 2017, 31(12): 14248-14261.
19	Snider D M , Clark S M , O'Rourke P J . Eulerian-Lagrangian method for three-dimensional thermal reacting flow with application to coal gasifiers[J]. Chemical Engineering Science, 2011, 66(6): 1285-1295.
20	Gidaspow D . Multiphase Flow and Fluidization: Continuum and Kinetic Theory Descriptions[M]. Academic Press, 1994.
21	Harris S E , Crighton D G . Solitons, solitary waves, and voidage disturbances in gas-fluidized beds[J]. Journal of Fluid Mechanics, 1994, 266: 243-276.
22	Kirnbauer F , Hofbauer H . Investigations on bed material changes in a dual fluidized bed steam gasification plant in Gussing, Austria[J]. Energy & Fuels, 2011, 25(8): 3793-3798.
23	Yu J , Yao C , Zeng X , et al . Biomass pyrolysis in a micro-fluidized bed reactor: characterization and kinetics[J]. Chemical Engineering Journal, 2011, 168(2): 839-847.
24	Yoon H , Wei J , Denn M M . A model for moving‐bed coal gasification reactors[J]. AIChE Journal, 1978, 24(5): 885-903.
25	Syamlal M , Bissett L A . METC gasifier advanced simulation (MGAS) model[J]. Technical Note, 1992. DOI: 10.2172/10127635 DOI
26	Howard J B , Williams G C , Fine D H . Kinetics of carbon monoxide oxidation in postflame gases[J]. Symposium (International) on Combustion, 1973, 14(1): 975-986
27	Mitani T , Williams F A . Studies of cellular flames in hydrogen oxygen nitrogen mixtures[J]. Combustion and Flame, 1980, 39(2): 169-190.
28	Dryer F L , Glassman I . High-temperature oxidation of CO and CH₄ [J]. Symposium (International) on Combustion, 1973, 14(1): 987-1003.
29	Kaushal P , Pröll T , Hofbauer H . Model development and validation: co-combustion of residual char, gases and volatile fuels in the fast fluidized combustion chamber of a dual fluidized bed biomass gasifier[J]. Fuel, 2007, 86(17/18): 2687-2695.
30	Westbrook C K , Dryer F L . Simplified reaction mechanisms for the oxidation of hydrocarbon fuels in flames[J]. Combustion Science and Technology, 1981, 27(1/2): 31-43.
31	Lu X , Wang T . Water–gas shift modeling in coal gasification in an entrained-flow gasifier(1): Development of methodology and model calibration[J]. Fuel, 2013, 108: 629-638.
32	Li T , Dietiker J , Shadle L . Comparison of full-loop and riser-only simulations for a pilot-scale circulating fluidized bed riser[J]. Chemical Engineering Science, 2014, 120: 10-21.

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