二氧化碳併合吸收與氣提薄膜模組之實驗研究

Experimental study of hybrid absorption and stripping membrane contactors for carbon capture

潘人豪(Pan Ren-Hao)

指導教授 ： 張煖

淡江大學/工學院/化學工程與材料工程學系碩士班/碩士(2017年)

https://doi.org/10.6846/TKU.2017.00698

摘要

物理性吸收技術之能耗低於二氧化碳化學吸收技術，然而僅適用於高二氧化碳分壓系統。本研究團隊提出創新的二氧化碳併合吸收與氣提薄膜模組(HASMC)，可藉由同時進行吸收與氣提，提升應用於低二氧化碳分壓系統之物理吸收性能。本論文利用氣液通道交錯配置之併合吸收與氣提薄膜模組進行單純吸收(A)、平行式吸收氣提(P-AS)與交錯式吸收氣提(C-AS)三種操作模式之實驗研究，並使用建立於Aspen Custom Model (ACM)平台之數學模式進行模擬研究。本研究使用之物理吸收劑為碳酸丙烯酯與疏水性PTFE薄膜。實驗模組包括液體通道水力直徑高低之兩種模組，CS2與CS1。
實驗研究顯示CS1與CS2之吸收通量強化因子(相對於單純吸收)於平行式操作分別為1.17-1.58倍與1.16-1.61倍，交錯式操作則為1.61-2.21倍與1.55-2.15倍。交錯式之強化效果顯著高於平行式模組，CS2模組之強化效果則略微高於CS1模組。此外，強化效果於較低氣體濃度時較高。模擬與實驗結果相當接近，均獲得吸收與氣提通量均隨煙道氣流速、煙道氣濃度與液體流速之提高而增高。模擬結果也揭露交錯式吸收氣提操作之高強化效果是因吸收薄膜之液體邊界層可經由緊接於吸收薄膜後方之氣提薄膜面氣提操作而獲得有效再生。

關鍵字

薄膜接觸器 ； 物理吸收 ； 薄膜吸收 ； 薄膜氣提 ； 二氧化碳 ； 碳捕捉

並列摘要

Physical absorption for post-combustion carbon capture is less energy consuming than chemical absorption, however, it is only feasible for the treatment of high-partial-pressure carbon dioxide gases. A novel hybrid absorption/stripping membrane contactors (HASMC) is proposed for the treatment of low-partial-pressure carbon dioxide gases. The HASMC can effectively enhance the operation performance by simultaneous absorption and stripping in a single module. In this thesis, experiments of HASMC under three operation modes have been conducted, including pure absorption (A) as well as parallel-type and cross-type absorption and stripping (P-AS and C-AS). Simulation results are presented for these operation modes too. The physical absorbent and the membrane used are propylene carbonate and commercial PTFE (Polytetrafluoroethylene), respectively. Modules with two different hydraulic diameters were used for the experimental study.
The enhancement factors of absorption flux relative to pure absorption for P-AS and C-AS are 1.16-1.61 and 1.61-2.21, respectively. The module with smaller hydraulic diameter gives higher absorption and stripping fluxes. Experimental and simulation results indicate that both absorption and stripping fluxes increase with flue gas flowrate, flue gas concentration and liquid flow rate. The simulation reveals the absorption flux enhancement results from the refreshing of the liquid concentration boundary layer by the stripping membrane immediately following the absorption operation.

並列關鍵字

Hybrid modules ； Membrane absorption ； Membrane stripping ； Parallel flow ； Cross-flow ； Carbon Capture ； Solvent Absorption ； Membrane Contactor ； Absorption ； Stripping

參考文獻

Amrei, S.M.H.H., Memardoost, S., Dehkordi, A.M., Comprehensive modeling and CFD simulation of absorption of CO2 and H2S by MEA solution in hollow fiber membrane reactors, AIChE Journal, 60, 657-672, 2014.

Chang, H., Hsu, J.A., Chang, C.L, Ho, C.D., CFD study of heat transfer enhanced membrane distillation using spacer-filled channels, Energy Procedia, 75, 3213-3219, 2015a.

Chang, H., Hsu, J.A., Chang, C.L., Ho, C.D., CFD simulation of direct contact membrane distillation modules with rough surface channels, Energy Procedia, 75, 3083-3090, 2015b.

Chang, H., Hsu, J.A., Chang, C.L., Ho, C.D., Cheng, T.W., Simulation study of transfer characteristics for spacer-filled membrane distillation desalination modules, Applied Energy, 185, 2045-2057, 2017.

Chernyshov, M. N., Meindersma, G. W., de Haan, A.B., Comparison of Spacers for Temperature Polarization Reduction in Air Gap Membrane Distillation, Desalination,183, 363-374., 2005.