【作者】 吴沪宁；

【导师】 冯晖；

【作者基本信息】 南京工业大学 ， 化学工程， 2004， 硕士

【摘要】 本文采用纳滤膜对宜兴申新染料厂生产的活性紫染料液进行了脱盐浓缩的渗滤过程研究,分别选用 DK、DL 和 NF270 三种带负电的纳滤膜进行了实验,从中选择出对活性紫染料液透过通量大、除盐效果好以及染料损耗低的一种纳滤膜 DK,再用该纳滤膜对活性紫工业染料液的脱盐浓缩间歇恒容渗滤过程进行了实验。实验结果显示:在 25℃温度和 1.0MPa 的压力条件下,该膜对活性紫染料的截留率接近 100%,经过九次加水浓缩的间歇恒容渗滤操作,染料纯度从 84%提高到 99%以上,同时料液被浓缩了 3 倍,达到了厂家提出的要求,说明采用纳滤膜的间歇渗滤操作过程能够实现活性紫粗制染料溶液的脱盐和浓缩目的。 接着,本文对该活性染料液体系提出了能够达到脱盐和浓缩目的的三种渗滤工艺过程,即间歇恒容渗滤过程、预浓缩-连续恒容渗滤-后浓缩组合工艺过程和连续变容渗滤过程,并对这三个渗滤工艺进行了模拟计算和比较,用于预测纳滤膜对活性紫染料液进行渗滤操作过程中各过程参数的变化,从而确定过程时间最短和水消耗量最小的渗滤工艺及工艺参数,为实际的工业应用提供理论指导。(1)对于间歇恒容渗滤过程,通过研究不同的浓缩倍数(1.5、2 和 3)和稀释倍数(1.5、2 和 3)对脱盐浓缩效果的影响,发现要达到相同的浓缩倍数和染料纯度,浓缩-稀释-浓缩形式的间歇恒容渗滤过程所用过程时间以及要消耗的渗滤溶剂量要小于稀释-浓缩-稀释形式的间歇恒容渗滤过程。对于浓缩-稀释-浓缩过程的渗滤操作而言,浓缩倍数大的过程,所用的过程时间和渗滤溶剂量要小(2)对于预浓缩-连续恒容渗滤-后浓缩组合工艺过程,通过研究不同的预浓缩倍数(1.5、2和 3)对过程参数的影响,发现达到相同的浓缩倍数和染料纯度时,预浓缩 3 倍的组合过程所需总过程时间最短,所消耗的渗滤溶剂量也最少。(3)对于连续变容渗滤过程,研究了不同的最终染料浓度以及除盐要求对过程参数的影响。结果表明,如果最终除盐要求相同而染料浓度高,则需要较长的过程时间和较小的水消耗量;如果相同染料浓度相同而除盐要求高,则需要的较长过程时间和较大的水消耗量。 最后,通过比较发现利用以上三种渗滤过程对活性紫染料进行纯化和浓缩时,达到相同的脱盐和浓缩目标,预浓缩-连续恒容渗滤-后浓缩组合工艺过程所 I<WP=4>用过程时间以及所消耗的渗滤溶剂水量要小于间歇恒容渗滤过程和连续变容渗滤过程,预浓缩倍数为 3 的组合过程所需的过程时间和水消耗量在所有的渗滤过程中是最小的,所以采用预浓缩 3 倍的组合过程对活性紫染料进行脱盐浓缩效果最佳。通过计算,本文最后得到了宜兴申新染料厂采用纳滤方法浓缩纯化其生产的活性紫染料所需的膜面积和耗水量,以便为下一步实际应用提供理论指导。更多还原

【Abstract】 Batch diafiltration experiments of industrial reactive purple dye solution werecarried out by using the three kinds of NF membranes which were DK (DesalinationCorporation), DL(Desalination Corporation) and NF270 (DOW Chemical Corporation)membranes, in order to choose the nanofiltration membrane having high permeationflux, low rejection of NaCl component and high rejection of dye. Thus, the DKmembrane in the operation mode of batch diafiltration was used for the concentrationand desalination of reactive purple dye solution. Under the temperature 25℃ andapplied pressure of 1.0MPa, observed rejection of dye component reached 100%.After nine-stage batch diafiltration operation, concentration of dye increased (去除to)3 times, and the purity of reactive dye increased from 84% to 99%. Theexperimental results showed that nanofiltration membrane DK in batch diafiltrationoperation mode was applicable to desalination and concentration of reactive dyesolution. Next, for the purpose of desalination and concentration of the reactive dyesolution, batch constant volume diafiltration process, combined process ofpreconcentration phase- continuous constant volume diafiltration phase- postconcentration phase and continuous variable volume diafiltration process werestudied. These separation and purification processes were simulated and used topredict the changes of process parameters. The work will provide useful theoreticalguide for the engineering application and embody its value. (1) The simulation ofbatch constant volume diafiltration process was used to determine the effects of thevolume concentration factor (1.5, 2, 3) on desalting and purifying of dye solution. Thesimulative results suggested that to obtain the same concentration of NaCl and purityof dye in the retentate, the higher concentration factor is, the less process time andwater quantity are required for the processed volume . With the times increased of therepeated operations of concentration-dilution , the salt concentration in the retenatewas descreased. (2) The simulation of three-phrase combined process was used todetermine the effects of the volume concentration factor in pre-concentration phase(1.5, 2, 3) on the process parameters, and the process time was optimized. For theminimum consumption of process time, the optimum value of dye concentration at i<WP=6>diafiltration was 0.264mol/L. Thus, to obtain the same concentration of NaCl and dyecomponent in the retentate, the optimum appears to be a combined process where thefeed was first pre-concentrated about 3 times by nanofiltration, followed bycontinuous constant volume diafiltration and post-concentration. The required volumeof added water depended on volume concentration factor in pre-concentration phase,salt rejection and desired salt concentration in the retentate. (3) The simulation ofcontinuous variable volume diafiltration process was to discuss the effect of finalconcentration of dye and salt in the retentate. The simulative results showed that if thesame salt concentration are obtained in the retentate, the higher the dye concentration,the longer the process time and the less volume required of added water; and if thesame dye concentration are obtained in the retentate, the lower the salt concentration,the longer the process time and the more volume required of water added. When the same dye and salt concentration (Cdye/Cdye,0 = 3, Csalt,0/Csalt = 16) areachieved, those three processes were compared. The total process time and requiredvolume of added water in the combined process were least, compared with the othertwo processes.更多还原