横向流超滤膜污染动力学模型

从超滤过程中面滤饼层内对流传输、反向传输和颗粒积累的质量平衡关系出发，建立了描述渗透通量随时间变化关系的横向流超滤膜污染动力学模型，该模型将通常难以确定的滤饼层比阻和反向扩散系数包含在两个经验参数a,b中，通过简单的实验确定参数值后，即可用于横向流超滤过程的数学模拟，模拟计算结果与实验实测数据比较接近，且从理论上说明了横向流超滤从非平衡到最终平衡过渡的原理以及半透膜压，膜面剪切率对渗透通量的影响。     

荷电超滤膜的研究：Ⅰ.氯甲基化聚砜超滤膜的研究

膜材料本身的性质是决定膜性能的主要因素，对于荷电超滤膜，荷电性和荷电程度对膜性能有较大的影响，本文研究了含氯量对氯甲基化聚砜超滤膜性能的影响，就有关制膜条件对膜的物理性能和电性能的影响也进行了研究。     

The identification of readily bioavailable pollutants in lake shkodra/skadar using semipermeable membrane devices (SPMDs), bioassays and chemical analysis

GOAL, SCOPE AND BACKGROUND: Lake Shkodra/Skadar is the largest lake in the Balkans region and located on the border between Albania to the south and Montenegro to the north. Because of the wide range of endemic, rare or endangered plant and animal species it supports, Lake Shkodra/Skadar and its extensive associated wetlands are internationally recognised as a site of significance and importance (Ramsar site). In recent years, social and economic changes in both Albania and Montenegro have lead to unprecedented levels of urban and industrial effluent entering the lake. Of particular concern is the increasing input of toxic hydrophobic organic pollutants (HOPs) into the lake and the degree to which these compounds are available for uptake by aquatic biota. Semipermeable membrane devices (SPMDs) have been shown to sample the readily bioavailable fraction (dissolved phase) of waterborne HOPs and in doing so provide relevant data for exposure assessment. The aim of the current study was to use SPMD-based sampling in conjunction with appropriate bioassays and chemical analysis to identify readily bioavailable HOPs in the lake. METHODS: SPMDs were constructed and deployed at three sites in the Albanian sector and three sites in the Montenegrin sector of Lake Skadar/Shkodra for 21 days. Following the dialytic recovery of target analytes and size exclusion chromatographic clean-up, aliquots of SPMD samples were subjected to GC-MS scan analysis for major components, GC-MS SIM analysis for 16 priority pollutant polycyclic aromatic hydrocarbons (PP-PAHs) and assayed for EROD-inducing, estrogenic and mutagenic potential using rainbow trout liver cells (RTL-W1), the yeast estrogen screen (YES) and the Ames Test, respectively. RESULTS AND DISCUSSION: A total of 39 compounds were tentatively identified in SPMD samples from the six sampling sites. Alkylated PAHs were the most abundant and ubiquitous compounds present along with various sterols and sterol derivatives. Numerous other compounds remain unidentified. 15 of the 16 targeted PP-PAHs were present in samples from one or more of the sampling sites indicating these compounds are both readily bioavailable and widely distributed in Lake Shkodra/Skadar. Total PP-PAH concentrations ranged between 3991 ng/SPMD and 10695 ng/SPMD. Bioassays carried out on SPMD samples revealed significant EROD-inducing and estrogenic potential at five of the six sampling sites indicating toxicologically relevant compounds are readily available for uptake by resident aquatic biota. EROD-inducing potential was positively correlated with targeted PP-PAH concentration (r2 = 0.74). However, comparison of bioassay- and analytically-derived toxicity equivalents revealed targeted PP-PAHs were responsible for less than 0.06% of the total EROD-inducing potential. CONCLUSIONS AND OUTLOOK: The combination of SPMD-based sampling with appropriate bioassays and chemical analysis provided an effective tool for the identification of environmentally relevant waterborne pollutants in Lake Shkodra/Skadar. Our results show that toxicologically relevant HOPs including EROD-inducing and potentially estrogenic compounds are widely distributed in the lake and readily available for uptake by aquatic biota. Our results also suggest that alkylated PAHs rather than parent compounds may be of greater toxicological relevance in the lake. As anthropogenic influences continue to increase, SPMD-based sampling is expected to play a central role in future research concerned with the identification, monitoring and assessment of the risk posed by HOPs to Lake Shkodra/Skadar's aquatic biota.     

聚醚砜纳滤膜的制备及改性研究进展

聚醚砜是一种性能优异的纳滤膜材料,具有耐热、耐压、耐燃、耐辐射、抗酸、抗氧化、抗溶剂、生物相容性好等优点,应用前景十分广阔。文章重点介绍了相转化法、共混法、荷电法、复合法等聚醚砜纳滤膜制备方法,以及表面涂覆、材料共混等物理改性方法和膜材料本体改性、膜表面接枝改性等化学改性方法,阐述研究现状,并予以评价,同时提出探索新的制膜及改性方法,降低膜成本,提高制膜过程中的环境友好性,是聚醚砜纳滤膜制备及改性的重要发展方向。     

微藻对海水养殖循环水高效碳氮磷一体化去除的研究

海水养殖循环水高盐分和波动的低碳氮比造成水处理困难和亚硝酸盐累积,影响循环水处理利用,其排放造成受纳海域生态环境破坏.本研究采用混合营养型钝顶螺旋藻结合膜光合反应器（MPBR）考察碳氮比对海水养殖循环水碳、氮、磷一体化去除效率及藻生物质产量的影响.结果表明,在原水碳氮比为5时,钝顶螺旋藻可实现碳、氮、磷高效一体化去除,出水COD低于20 mg·L^-1,满足《海水养殖水排放要求》（SC/T 9103—2007）一级标准,总氮和总磷浓度均满足二级标准.提高碳氮比有利于钝顶螺旋藻的生长、油脂累积和氮磷的去除,碳氮比为1~10时藻体内油脂含量由14.9%增到19.3%.钝顶螺旋藻膜光合反应器（MPBR）运行数据表明,聚偏二氟乙烯（PVDF）膜和无纺布生物膜均可高效稳定地截留微藻,稳定运行期出水COD、总氮和总磷浓度均满足《海水养殖水排放要求》（SC/T 9103—2007）二级标准,且均无亚硝酸盐累积.无纺布生物膜光合反应器COD去除效率（93.2%）和藻体的多糖含量（98.1 mg·g^-1）显著高于PVDF膜反应器（85.2%和70.4 mg·g^-1）,膜通量也较低,膜污染较轻.本研究中钝顶螺旋藻结合无纺布动态生物MPBR不仅实现了海水养殖循环水高效的碳、氮、磷同步去除,无亚硝酸盐累积,并可稳定收获生物质资源,为海水养殖循环水高效、安全处理和资源化利用提供依据.     

溶液环境对荷电超滤膜和传统中性超滤膜去除天然有机物的影响

以Aldrich 腐殖酸溶液为水样,研究比较了溶液环境(pH值、离子强度和钙离子)对荷电改性再生纤维素超滤膜和传统中性未改性再生纤维素超滤膜过滤过程的影响.结果表明, ①pH值主要通过质子化作用影响荷电膜以及腐殖酸分子的荷电量,进而影响荷电超滤过程.溶液pH值从7.5下降到3.5时,荷电超滤膜对腐殖酸的截留率从92%减少到79%,超滤4 h时,膜通量下降从26%增加到36%.②离子强度的改变是通过影响腐殖酸分子的物化性质和静电屏蔽作用来影响超滤过程的.当溶液离子强度为0、 3和100 mmol/L时,初始截留率依次降低,分别为92%、 87%和48%,超滤4 h时,荷电超滤膜的通量下降依次增加,分别为26%、 35%和63%.③Ca2+浓度的影响,需要综合考虑静电屏蔽作用、Ca2+的架桥作用以及滤饼层的压实性等各方面的影响.④pH值、离子强度和钙离子对中性超滤膜过滤行为的影响趋势与荷电超滤膜相似,但其影响程度有着较大的差别.研究结果对荷电超滤膜技术在实际应用中选择合适环境条件提供了参考.     

超滤法处理阴极电泳漆

报道了用荷正电的CM1中空纤维膜处理阴极电泳漆的研究,探讨了漆液循环速度、操作温度、操作压力、漆液浓度、运行时间等对膜传输性能的影响,研究了清洗对膜性能恢复的效果。实验证明,漆液中的固体份全部被截留,透过液清澈透明,在压力0.130MPa,漆液流量200—300ml/s,漆液温度30℃条件下,透过液通量可稳定在2.5—3.5ml/cm~2·h。     

固定化溶藻菌除藻效果研究

为了解固定化溶藻菌对藻类污染水源的治理效果,模拟动态膜生物反应器,将溶藻细菌RZ14菌株固定于膜组件,通过膜自生功能形成溶藻菌生物膜。采集水华水体作为进水水样,对水体中叶绿素a、有机质、氨氮及总磷变化进行跟踪测定。结果表明:结合DMBR工艺,投加溶藻菌RZ14菌株后,叶绿素a含量低于0.05mg/L,去除率接近100%,COD及BOD5去除率分别为50.08%和71.24%,氨氮及总磷去除率分别为70.73%和86.79%。将溶藻菌投加动态膜生物反应器,能快速消除水华现象,改善水质污染状况,对藻类污染水体治理效果显著。     

一种新型聚四氟乙烯膜在油田采出水的试验研究

本实验装置原水为大庆油田采出水,经过0.1μm聚四氟乙烯膜处理后要求达到SS≤1.0 mg/L、粒径中值≤1μm和0il≤5.0 mg/L的标准,然后再回注。实验结果表明:在预处理出水稳定在0il≤15.0 mg/L、SS≤5.0 mg/L、粒径中值≤3μm条件下,该水质作为膜系统的进水时,膜的出水水质中粒径中值不达标,SS和oil含量能达到设计要求。在预处理出水水质超出设计范围时,膜的出水水质中SS超标,而oil和粒径中值能达标。