为了提高碳酸氢铵-反向电渗析模块的产电性能，对其构型进行了优化，并分析了其能量效率的变化特点。结果表明，当碳酸氢铵-反向电渗析模块采用5对离子交换膜及0.2 mm厚的隔板时，其功率密度可达最大值0.85 W/m2（不计电极系统能量损耗）。膜对数量不超过8时，开路电压、内阻及最大功率密度均随膜对数的增加而逐渐升高，且膜对数与开路电压、内阻均呈现出良好的线性关系；膜对数量大于8时，装置产电性能逐渐变差。对于相同种类的隔板，采用较薄的隔板能减小装置的内阻，其产电性能更好；对于同等厚度的隔板，编织结构紧密的隔板更优。实验中装置能量效率稳定于30%左右，表明其在能量利用方面具有一定优势。

 The configuration of a reverse electrodialysis (RED) stack utilizing ammonium bicarbonate solutions was optimized in order to improve the power output. The variation of energy efficiency was also analyzed. The results showed that a maximum power density of 0.85 W/m2 was achieved with the use of five cell pairs and a spacer with a thickness of 0.2 mm when ignoring the power consumption due to the electrode system. Whenthe number ofcell pairs ranged from 2 to 8, the open circuit voltage, internal resistance and maximum power density allimproved gradually with the increase of cell pairs. Meanwhile, the number of cell pairs had a good linear relationship with both the open circuit voltage and internal resistance. The RED stack instead had a reduced power output when the number of cell pairs was over 8. For two spacers with the same type, the thinner one resulted in a decreased internal resistance and thus increased thepower output. For the spacers with the same thickness, the one with a compact woven structure performed better. Energy efficiency of the RED stack stabilized at about 30% during the experiment, which shows it’s promising for energy utilization.
Key words: reverse electrodialysis; ammonium bicarbonate; waste heat; configuration

[1]Pattle R E. Production of electric power by mixing fresh and salt water in the hydroelectric pile [J]. Nature, 1954, 174(4431): 660.
[2]Post J W, Hamelers H V M, BuismanC J N. Influence of multivalent ions on power production from mixing salt and fresh water with a reverse electrodialysis system [J]. J Membr Sci, 2009, 330(1-2): 65-72.
[3]Turek M, Bandura B. Renewable energy by reverse electrodialysis [J]. Desalination, 2007, 205 (1-3): 67-74.
[4]Cusick R D, Kim Y, Logan B E. Energy capture from thermolytic solutions in microbial reverse-electrodialysis cells [J]. Science, 2012, 335(6075): 1474-1477.
[5]Luo Xi, Cao Xiaoxin, Mo Yinghui, et al. Power generation by coupling reverse electrodialysis and ammonium bicarbonate: Implication for recovery of waste heat [J]. Electrochem Commun, 2012, 19: 25-28.
[6]Chen Huijuan, Goswami D Y, Stefanakos E K. A review of thermodynamic cycles and working fluids for the conversion of low-grade heat [J]. Renew Sust Energ Rev, 2010, 14(9): 3059-3067.
[7]Tchanche B F, Lambrinos G, Frangoudakis A, et al. Low-grade heat conversion into power using organic Rankine cycles–A review of various applications [J]. Renew Sust Energ Rev, 2011, 15(8): 3963-3979.
[8]Veerman J, Saakes M, Metz S J, et al. Reverse electrodialysis: A validated process model for design and optimization [J].Chem Eng J, 2011, 166(1): 256-268.
[9]Veerman J, Saakes M, Metz S J, et al.Reverse electrodialysis: Performance of a stack with 50 cells on the mixing of sea and river water [J].J Membr Sci, 2009, 327(1-2): 136-144.
[10] Veerman J, Saakes M, Metz S J, et al.Electrical power from sea and river water by reverse electrodialysis: A first step from the laboratory to a real power plant [J]. Environ Sci Technol, 2010, 44(23): 9207-9212.
[11]Vermaas D A, Saakes M, Nijmeijer K. Power generation using profiled membranes in reverse electrodialysis [J]. J Membr Sci, 2011, 385-386: 234-242.
[12]Post J W, Hamelers H V M, BuismanC J N.Energy recovery from controlled mixing salt and fresh water with a reverse electrodialysis system [J].Environ Sci Technol, 2008, 42(15): 5785-5790.
[13]D?ugo?e?cki P, Gambier A, Nijmeijer K, et al. Practical potential of reverse electrodialysis as process for sustainable energy generation [J]. Environ Sci Technol, 2009, 43(17): 6888-6894.
[14]Veerman J, Saakes M, Metz S J, et al. Reverse electrodialysis: evaluation of suitable electrode systems [J]. J ApplElectrochem, 2010, 40(8): 1461-1474.
[15]D?ugo?e?cki P, D?browska J, Nijmeijer K, et al.Ion conductive spacers for increased power generation in reverse electrodialysis [J]. J Membr Sci, 2010, 347(1-2): 101-107.
[16]Veerman J, Jong R M D, Saakes M,et al.Reverse electrodialysis: Comparison of six commercial membrane pairs on the thermodynamic efficiency and power density [J]. J Membr Sci, 2009, 343(1-2): 7-15.
[17]Kim Y, Logan B E. Microbial reverse electrodialysis cells for synergistically enhanced power production [J]. Environ Sci Technol, 2011, 45(13): 5834-5839.
[18]Veerman J, Post J W, Saakes M, et al.Reducing power losses caused by ionic shortcut currents in reverse electrodialysis stacks by a validated model [J]. J Membr Sci, 2008, 310(1-2): 418-430.