利用双套型微孔疏水中空纤维膜制作的膜接触器脱除水溶液中氨的传质机理，建立了过程传质模型。考察了多种实验条件变化对其传质性能的影响；系统比较了双膜型膜接触器与传统单膜型膜接触器的性能差异。实验结果表明，新型膜器减少了渗透蒸馏效应对副产品铵盐溶液的稀释作用，在相同操作条件下，所得副产物(NH4)2SO4溶液浓度值比传统膜器高出29%；当吸收液中氢离子摩尔流率是料液中氨摩尔流率的1.2倍或更低时，新型膜器的总传质系数比传统膜器高6倍以上，这表明双套膜器克服了传统膜器中由于壳程非理想流动导致的明显传质阻力。用预处理后的垃圾渗滤液作含氨料液的600天长期实验结果表明双套膜型膜器的潜在使用寿命远远高出传统膜器。%Removal of ammonia from aqueous solutions using a dual-hollow fiber membrane contactor (which contains two sets of hydrophobic microporous hollow fibers) was investigated, and a theoretical model was developed to simulate the experimental results. The influence of various experimental parameters on the performance of the new membrane contactor was studied and compared with traditional membrane contactors under similar operation conditions. Experimental results show that the concentration of the by-product (ammonium sulfate solution) obtained by the new contactor is 29% higher than that from the traditional one, due to the osmotic distillation reducing effect. When the hydrogen ion molar flow rate in the stripping solution is 1.2 times lower than that of ammonia in the feed solution, the overall mass transfer coefficient K of the new contactor is >6 times higher than that of the traditional one. This result indicates that the new contactor overcomes the obvious shell mass transfer resistance caused by non-ideal flow in the traditional module. The long-term experiment lasting 600 days using pretreated landfill leachate as feed shows that the potential working life of the new contactor is much longer.
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