【作者】 潘自鼎；

【导师】 吴燕翔；

【作者基本信息】 福州大学 ， 化学工程， 2004， 硕士

【摘要】 本工作采用的支撑液膜体系，是以 D2EHPA（二（2－乙基己基）膦酸）为载体，正庚烷、煤油和癸醇三种物质作为膜溶剂，聚丙烯为支撑体材料。本研究探讨了氨（铵）在支撑液膜中传质机理，考察各因素对渗透系数的影响，建立氨（铵）在中空纤维型支撑液膜的传质模型，并对传质渗透过程进行模拟。首先，测定包括分配系数、水相传质扩散系数和反应平衡常数等基础参数，并分析了各操作条件对其影响。分配系数的研究结果表明，分配系数Kp随着料液氨（铵）浓度和pH值增大而增大，以正庚烷为膜相的Kp比煤油和癸醇的相对较大；采用多孔板法测定水相中NH4＋和NH3扩散系数，并将测定值与经验公式估算值进行对比，结果表明，测定结果是可靠的；反应常数Kr随着载体浓度升高而增大，正庚烷为载体溶剂时Kr最大，pH值对Kr的影响较大，Kr随料液pH值减小而增大。其次，采用间歇平板支撑液膜，简化操作条件，使总传质阻力的变化只与膜相阻力有关，而与料液相和反萃相阻力无关的前提下，研究膜内传质过程，并归结出氨（铵）在支撑液膜内传质模型，求解膜内扩散系数等模型参数，为中空纤维连续传质数学模拟打下基础。实验结果表明，搅拌速率达到800rpm以上时，总传质阻力的变化与料液相阻力无关；膜相中无载体和含有载体的情况，反萃相pH值分别小于2和3时，总传质阻力的变化与反萃相阻力无关。最后，考察操作条件例如膜溶剂种类、载体浓度、料液和反萃相pH值、以及进料速度等对氨（铵）对k值的影响；建立中空纤维连续传质数学模型，利用模型模拟分析几何尺寸、支撑体性能参数以及操作条件对体系传质过程的影响。实验结果表明，所建立的数学模型与实验值比较吻合。以上的研究为支撑液膜法处理氨氮废水技术中液膜体系的选择、工艺过程优化等提供了理论指导和依据，为实际应用奠定一定的基础。更多还原

【Abstract】 In the present dissertation, a system of supported liquid membrane has been selected: D2EHPA used as carrier; decanol, kerosene and hexylmethane respectively used as the diluents; and polypropylene as membrane support material. The mechanism of ammonia (ammonium) transporting through the SLM and the factors affecting the permeability coefficient are investigated. At last, model of mass transfer across the supported liquid membrane is established, by which the mass transfer is simulated. Firstly, allocation coefficient, diffusion coefficient and reversible reaction equilibrium const are determined, and the operation factors affecting these parameters also investigated. The results obtained show that Kp value increases with the increasing of the initial concentration and pH value of the feed phase, using hexylmethane as diluent has higher Kp value than decanal and kerosene; the determined diffusion coefficients show little difference with the values that are calculated by the experiential equation given by Reid-Sherwood and Wilke-Chang; Kr increases as the carrier concentration increases, using hexylmethane as dilute has larger Kr value than the other two, Kr value increases with the decreasing of pH value in the feed phase, and is varied with pH value sharply.Secondly, relatively more ideal condition is investigated under which the total transport resistance is independent of the feed and strip resistance, that is, the main resistance is concentrated in the membrane. Under these conditions, the permeation process in the flat-sheet-supported liquid membrane is investigated, the model of the transport of NH3-N in membrane is established, and the parameters of the model are solved. The results show that when the stirring speed reaches 800 rpm, the total transport resistance is independent of the feed resistance; when there is no carrier in the membrane, or there is some proportion of carrier in the membrane, if the pH value is less than 2 or 3 respectively, the total transport resistance is independent of the strip resistance. <WP=4>Lastly, the factors affecting slope k such as the type of solvent, proportion of D2EHPA in the membrane, pH value of the feed and the strip, and the feed speed, are investigated. The model of the transport of NH3-N through hollow fiber liquid membrane is established. Using this model, the effects of the geometry dimension and property parameters of membrane support material and operation conditions on mass transport are analyzed. The results show that the model is consistent to the experiment date.The present research provide the theoretic guidance and foundation for the selection of SLM system and the optical of operation condition, and it lay some foundation for the practical application of the removal of ammonia nitrogen from waste water using SLM technology.更多还原