π型向心徑向流吸附器氣?固兩相模型傳熱傳質特性

王浩宇; 劉應書; 張傳釗; 陳福祥; 馬曉鈞; 李春旺

doi:10.13374/j.issn2095-9389.2019.03.26.001

π型向心徑向流吸附器氣?固兩相模型傳熱傳質特性

doi: 10.13374/j.issn2095-9389.2019.03.26.001

1.
北京聯合大學生物化學工程學院，北京 100023
2.
北京科技大學能源與環境工程學院，北京 100083

基金項目: 北京市自然科學基金資助項目(8182019)；北京市教育委員會科技計劃一般資助項目(KM201711417014)；國家自然科學基金資助項目(51578065)

詳細信息

通訊作者:
E-mail：zhangchuanzhao@buu.edu.cn

中圖分類號: TG142.71
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出版歷程
- 收稿日期: 2019-03-26
- 刊出日期: 2019-11-01

Heat and mass transfer characteristics of the gas?solid two-phase model in a π-shaped centripetal radial flow adsorber

1.
College of Biochemical Engineering, Beijing Union University, Beijing 100023, China
2.
School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China

More Information

Corresponding author: E-mail: zhangchuanzhao@buu.edu.cn

摘要

摘要: 為了明確徑向流吸附器變壓吸附制氧的傳熱傳質規律并提高制氧效率，建立π型向心徑向流吸附器（CP-π RFA）的氣固耦合兩相吸附模型，通過計算流體力學方法對能量模型、吸附熱以及顆粒尺寸等因素進行了數值模擬。結果表明：單相模型在加壓過程和吸附過程中床層內最高溫度分別為309.19 K和311.63 K，氧氣摩爾分數最高值分別為55.66%和62.65%；同等條件下兩相模型在加壓過程和吸附過程中床層內最高溫度分別為302.27 K和305.29 K，氧氣摩爾分數最高值分別為57.51%和66.02%。未考慮吸附熱的加壓過程和吸附過程床層內最高溫度分別為293.5 K和293.9 K，氧氣摩爾分數最高值分別為59.25%和72.18%；同等條件下考慮吸附熱時在加壓過程和吸附過程中床層內最高溫度分別為302.3 K和305.3 K，氧氣摩爾分數最高值分別為57.51%和66.02%。隨著顆粒直徑的增加，出口產品氣的氧氣摩爾分數逐漸下降，同時產品氣流量與回收率逐漸增加，顆粒直徑1.6 mm為最佳吸附劑顆粒直徑。本實驗獲得了吸附器內部傳熱傳質規律，為CP-π RFA用于變壓吸附制氧提供重要的技術參考。
- 徑向流 /
- 吸附 /
- π型向心 /
- 兩相流 /
- 數值模擬
Abstract: In order to investigate the heat and the mass transfer during pressure swing adsorption (PSA) for oxygen production and improve oxygen production efficiency, a gas-solid two-phase pressure swing adsorption model was established for the π-shaped centripetal radial flow adsorber (CP-π RFA). The energy model, the adsorption heat, and the particle diameter were comparatively studied using this model. The results show that the maximum temperature in the adsorbent bed during pressurization with air (PR) and high-pressure feed (AD) processes for the single-phase model are 309.19 K and 313.63 K, respectively. The highest oxygen mole fractions in the adsorbent bed during PR step and AD step using the single-phase model are 55.66% and 62.65%, respectively. Under the same operating conditions, the maximum temperature in the adsorbent bed during the PR and AD steps for the two-phase model are 302.27 K and 305.29 K, respectively. The highest oxygen mole fractions in the adsorbent bed during PR step and AD step using the two-phase model are 57.51% and 66.02%, respectively. For no-adsorption heat, the maximum temperatures are 293.5 K and 293.9 K, respectively, and the highest oxygen mole fractions in the adsorbent bed during the PR step and AD step with no-adsorption heat are 59.25% and 72.18%, respectively. However, the maximum temperature in the bed during the two steps with adsorption heat are 302.3 K and 305.3 K, respectively, and the highest oxygen mole fractions are 57.51% and 66.02%, respectively. As the particle diameter increases, the highest oxygen mole fraction of the outlet would decrease, while the oxygen flow rate and recovery would increase. The adsorbent with a particle diameter of 1.6 mm is the best size. The laws of the heat and the mass transfer in the adsorber can provide an important technical reference for CP-π RFA in the PSA for oxygen production.
- radial flow /
- adsorption /
- π-shaped centripetal /
- two phase flow /
- numerical simulation

HTML全文

圖 1 π型向心徑向流吸附器的結構示意圖. （a）流動型式；（b）三維模型；（c）網格劃分圖

Figure 1. Structure of CP-π RFA：（a）flow pattern；（b）3D model；（c）grid graph

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圖 2 網格無關性檢驗

Figure 2. Test of mesh independence

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圖 3 單組分N₂和O₂的吸附平衡曲線模擬結果與文獻對比

Figure 3. Comparison of the simulation results of adsorption equilibrium curves for single component N₂ and O₂ and literature reported

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圖 4 能量模型對π型向心徑向流吸附器在變壓吸附制氧過程中溫度云圖的影響. （a）兩相模型?加壓過程；（b）單相模型?加壓過程；（c）兩相模型?吸附過程；（d）單相模型?吸附過程

Figure 4. Effect of energy model on temperature distribution of CP-π RFA in PSA oxygen production：（a）two phase?Pr；（b）single phase?Pr；（c）two phase?Ad；（d）single phase?Ad

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圖 5 能量模型對π型向心徑向流吸附器在變壓吸附制氧過程中溫度的影響曲線

Figure 5. Effect of energy model on temperature profiles of CP-π RFA in PSA oxygen production

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圖 6 能量模型對π型向心徑向流吸附器在變壓吸附制氧過程中O₂摩爾分數云圖的影響. （a）兩相模型?加壓過程；（b）單相模型?加壓過程；（c）兩相模型?吸附過程；（d）單相模型?吸附過程

Figure 6. Effect of energy model on oxygen distribution of CP-π RFA in PSA oxygen production：（a）two phase?Pr；（b）single phase?Pr；（c）two phase?Ad；（d）single phase?Ad

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圖 7 能量模型對π型向心徑向流吸附器在變壓吸附制氧過程中氧氣摩爾分數的影響曲線

Figure 7. Effect of energy model on oxygen mole fraction profiles of CP-π RFA in PSA oxygen production

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圖 8 吸附熱對變壓吸附制氧過程中溫度云圖的影響. （a）兩相模型?考慮吸附熱的加壓過程；（b）單相模型?未考慮吸附熱的加壓過程；（c）兩相模型?考慮吸附熱的吸附過程；（d）單相模型?未考慮吸附熱的吸附過程

Figure 8. Effect of absorption on temperature distribution in PSA oxygen production：（a）two phase?adsorption heat-Pr；（b）single phase?no adsorption heat-Pr；（c）two phase?adsorption heat-Ad；（d）single phase?no adsorption heat-Ad

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圖 9 吸附熱對徑向流變壓吸附制氧過程中溫度曲線的影響

Figure 9. Effect of adsorption heat on temperature profiles in PSA oxygen production

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圖 10 吸附熱對變壓吸附制氧過程中氧氣摩爾分數云圖的影響. （a）兩相模型?考慮吸附熱的加壓過程；（b）單相模型?未考慮吸附熱的加壓過程；（c）兩相模型?考慮吸附熱的吸附過程；（d）單相模型?未考慮吸附熱的吸附過程

Figure 10. Effect of absorption heat on oxygen distribution in PSA oxygen production：（a）two phase?adsorption heat-Pr；（b）single phase?no adsorption heat-Pr；（c）two phase?adsorption heat-Ad；（d）single phase?no adsorption heat-Ad

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圖 11 吸附熱對徑向流變壓吸附制氧過程中氧氣摩爾分數的影響曲線

Figure 11. Effect of adsorption heat on oxygen mole fraction profiles in PSA oxygen production

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圖 12 顆粒直徑對吸附性能影響云圖. （a）d_p=0.4 mm；（b）d_p=1.6 mm；（c）d_p=2.8 mm；（d）d_p=4.0 mm；（e）d_p=5.2 mm

Figure 12. Effect of particle diameter on adsorption property：（a）d_p=0.4 mm；（b）d_p=1.6 mm；（c）d_p=2.8 mm；（d）d_p=4.0 mm；（e）d_p=5.2 mm

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圖 13 吸附劑顆粒直徑對氧氣摩爾分數及出口產品氣流量的影響

Figure 13. Effect of particle diameter on oxygen mole fraction and product flow rate

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圖 14 顆粒直徑對床層內氧氣摩爾分數沿徑向變化影響曲線

Figure 14. Effect of particle diameter on oxygen mole fraction profiles at the axial center position

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圖 15 顆粒直徑對床層內氧氣回收率的影響

Figure 15. Effect of particle diameter on oxygen recovery

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表 1 π型向心徑向流吸附器的結構參數

Table 1. Structure parameters of CP-π RFA

結構參數	數值	結構參數	數值
吸附器殼內徑/mm	219	外流道氣流分布孔直徑/mm	8
外分布筒內徑/mm	211	外流道氣流分布孔開孔率/%	3.6
吸附劑套筒內徑/mm	153	中心流道氣流分布孔直徑/mm	4
中心流道內徑/mm	26	中心流道氣流分布孔開孔率/%	25.5
氣流分布孔厚度/mm	3	吸附劑堆填高度/mm	187

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表 2 π型向心徑向流吸附器制氧循環過程的初始條件

Table 2. Initial conditions for the oxygen production of CP-π RFA

參數	數值
氣體摩爾分數	21%O₂，79%N₂
壓力/Pa	101325
氣相溫度/K	293
固相溫度/K	293
氣相氧氣質量分數	0.233
單位質量吸附劑氧氣吸附量/(mol·kg^?1)	0.0262832
單位質量吸附劑氮氣吸附量/(mol·kg^?1)	0.6328067

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表 3 吸附劑顆粒具體參數

Table 3. Specific parameters of absorbent particles

床層孔隙率	顆粒密度${\rho _{\rm{p}}}$/(kg·m^?3)	直徑${d_{\rm{p}}}$/mm	比熱容/(J·kg^?1·K^?1)
0.4	1035	1.6	1100

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表 4 組分氣體物性參數

Table 4. Physical parameters of component gas

組分氣體	摩爾質量/(g·mol^?1)	臨界溫度/K	臨界壓力/Pa	傳質系數/s^?1
O₂	32	154.4	5.04×106	62
N₂	28	126.1	3.39×106	19.7

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表 5 吸附等溫線參數

Table 5. Parameters of adsorption isotherm parameters

吸附質	k₁/(mol·kg^?1·Pa^?1)	k₂/K	k₃/Pa^?1	k₄/K	ΔH/(kJ·mol^?1)
O₂	7.87×10^?9	1541.211	6.79×10^?10	1968.24	12
N₂	9.86×10^?9	2010.908	1.67×10^?9	2250	18

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表 6 Skarstrom循環順序

Table 6. Skarstrom cycle sequence

循環順序	循環過程示意圖	時間/s
升壓		t₁=7
吸附		t₂=5
降壓		t₃=3
反吹		t₃=5

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表 7 吸附器1的邊界條件

Table 7. Boundary condition for adsorber 1

吸附器1邊界條件設置
口A	質量入口	質量入口	壓力出口	壓力出口
口B	壁	壓力出口	壁	質量入口
床壁	壁	壁	壁	壁
軸線	軸對稱	軸對稱	軸對稱	軸對稱

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參考文獻(26)

[1]	Chiang A S T, Hong M C. Radial flow rapid pressure swing adsorption. Adsorption, 1995, 1(2): 153 doi: 10.1007/BF00705002
[2]	Huang W C, Chou C T. Comparison of radial-and axial-flow rapid pressure swing adsorption processes. Ind Eng Chem Res, 2003, 42(9): 1998 doi: 10.1021/ie020129c
[3]	Dai Z S, Yu M, Rui D Z, et al. Investigation on a vertical radial flow adsorber designed by a novel parallel connection method. Chin J Chem Eng, 2018, 26(3): 484 doi: 10.1016/j.cjche.2017.11.005
[4]	Tian Q Q, He G G, Wang Z P, et al. A novel radial adsorber with parallel layered beds for prepurification of large-scale air separation units. Ind Eng Chem Res, 2015, 54(30): 7502 doi: 10.1021/acs.iecr.5b00555
[5]	Ruthven D M, Farooq S, Knaebel K S. Pressure Swing Adsorption. New York: VCH Publishers, 1994
[6]	Smolarek J, Leavitt F W, Nowobilski J J, et al. Radial Bed Vaccum/Pressure Swing Adsorber Vessel: US Patent, 5759242.1998−6−2
[7]	Genkin V S, Dilman V V, Sergeev S P. Distribution of a gas stream over height of a catalyst bed in a radial contact apparatus. Int Chem Eng, 1973, 13(1): 24
[8]	Zheng D X, Xie Z J, Bai L J. Prediction of adsorption breakthrough curves of the radical flow adsorber. J Xi'an Petrol Inst, 1990, 5(4): 31 鄭德馨, 謝志鏡, 白麗君. 徑向流吸附器吸附穿透曲線的計算. 西安石油學院學報, 1990, 5(4):31
[9]	Kareeri A A, Zughbi H D, Al-Ali H H. Simulation of flow distribution in radial flow reactors. Ind Eng Chem Res, 2006, 45(8): 2862 doi: 10.1021/ie050027x
[10]	Lu J L, Zhang X J, Qiu L M, et al. Theoretical analysis of uniform flow distribution in vertical radical adsorption bed. CIESC Journal, 2012, 63(Suppl 2): 21 陸軍亮, 張學軍, 邱利民, 等. 立式徑向流吸附器中流體均布的理論分析. 化工學報, 2012, 63(增刊 2): 21
[11]	Zhang X J, Wang X L, Lu J L, et al. Numerical simulation of vertical radical flow adsorber used in air separation unit. J Eng Thermophys, 2013, 34(5): 822 張學軍, 王曉蕾, 陸軍亮, 等. 空分用立式徑向流分子篩吸附器數值模擬. 工程熱物理學報, 2013, 34(5):822
[12]	Li R J, Zhu Z B. Investigations on hydrodynamics of multilayer π-type radial flow reactors. Asia-Pac J Chem Eng, 2012, 7(4): 517 doi: 10.1002/apj.601
[13]	Zhang X J, Lu J L, Qiu L M, et al. A mathematical model for designing optimal shape for the cone used in z-flow type radial flow adsorbers. Chin J Chem Eng, 2013, 21(5): 494 doi: 10.1016/S1004-9541(13)60527-3
[14]	Zhapbasbayev U K, Ramazanova G I, Kenzhaliev O B. Modelling of turbulent flow in a radial reactor with fixed bed. Thermophys Aeromech, 2015, 22(2): 229 doi: 10.1134/S0869864315020092
[15]	Wang H Y, Liu Y S, Meng Y. Effect of the gas distribution system structure of a radial flow adsorber on gas distribution. Chin J Eng, 2015, 37(1): 91 王浩宇, 劉應書, 孟宇. 徑向流吸附器布氣系統結構對布氣效果的影響. 工程科學學報, 2015, 37(1):91
[16]	Wang H Y, Liu Y S, Shi S S, et al. Influence of the structure of radial flow adsorbers on oxygen production with pressure swing adsorption. Chin J Eng, 2015, 37(2): 238 王浩宇, 劉應書, 施紹松, 等. 徑向流吸附器內部結構對變壓吸附制氧效果的影響. 工程科學學報, 2015, 37(2):238
[17]	Liu Y S, Zheng X G, Dai R F. Numerical study of flow maldistribution and depressurization strategies in a small-scale axial adsorber. Adsorption, 2014, 20(5-6): 757 doi: 10.1007/s10450-014-9619-7
[18]	Sun L M, Amar N B, Meunier F. Numerical study on coupled heat and mass transfers in an adsorber with external fluid heating. Heat Recovery Syst CHP, 1995, 15(1): 19 doi: 10.1016/0890-4332(95)90034-9
[19]	Zhu X Q, Liu Y S, Yang X, et al. Study of a novel rapid vacuum pressure swing adsorption process with intermediate gas pressurization for producing oxygen. Adsorption, 2017, 23(1): 175 doi: 10.1007/s10450-016-9843-4
[20]	Li Z Y, Liu Y S, Wang H H, et al. A numerical modelling study of SO₂ adsorption on activated carbons with new rate equations. Chem Eng J, 2018, 353: 858 doi: 10.1016/j.cej.2018.07.119
[21]	Li G, Xiao P, Zhang J, et al. The role of water on postcombustion CO₂ capture by vacuum swing adsorption: Bed layering and purge to feed ratio. AIChE J, 2014, 60(2): 673 doi: 10.1002/aic.14281
[22]	Yang X, Epiepang F E, Li J B, et al. Sr-LSX zeolite for air separation. Chem Eng J, 2019, 362: 482 doi: 10.1016/j.cej.2019.01.066
[23]	Epiepang F E, Yang X, Li J B, et al. Mixed‐cation LiCa‐LSX zeolite with minimum lithium for air separation. AIChE J, 2018, 64(2): 406 doi: 10.1002/aic.16032
[24]	Sorial G A, Granville W H, Daly W O. Adsorption equilibria for oxygen and nitrogen gas mixtures on 5a molecular sieves. Chem Eng Sci, 1983, 38(9): 1517 doi: 10.1016/0009-2509(83)80087-6
[25]	Fang L, Xiao J S, Benard P, et al. Thermal effects on pressure swing adsorption cycles for hydrogen purification. J Eng Thermophys, 2018, 39(5): 1104 方靚, 肖金生, 皮埃爾·貝納德, 等. 氫氣純化變壓吸附循環的熱效應. 工程熱物理學報, 2018, 39(5):1104
[26]	Prakash M J, Prasad M, Srinivasan K. Modeling of thermal conductivity of charcoal–nitrogen adsorption beds. Carbon, 2000, 38(6): 907 doi: 10.1016/S0008-6223(99)00202-X