Atmospheric bulk deposition of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in the vicinity of an iron and steel making plant

An IRA-743 resin bulk sampler was validated to monitor long-term bulk deposition of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). Six consecutive sampling campaigns (2008-2009) were conducted at four sites around steel complexes in Pohang, South Korea to investigate spatial and seasonal variations of PCDD/F bulk deposition. The bulk deposition within the steel complex showed the highest ∑_4-8PCDD/F (Tetra-Octa) fluxes, ranging from 204 to 608 (mean: 352) pg m⁻² d⁻¹, indicating steel complexes were major sources of PCDD/Fs. The homologue profiles were dominated with lower chlorinated PCDFs. Furthermore, the prevailing winds were confirmed to influence the spatial distribution of PCDD/F deposition. There were apparent seasonal variations of the bulk deposition at each site, and seasonal homologue patterns of PCDD/Fs were clearly observed. According to the passive air sampling, however, no significant seasonal change of ambient air concentrations of PCDD/Fs was observed. Therefore, it was concluded that the seasonal variations of deposition fluxes of PCDD/Fs probably resulted from temperature-dependent gas/particle partitioning.     

混凝-生物强化联合处理环氧树脂高盐废水

环氧树脂高盐废水是目前较难处理的工业废水之一.采用混凝联合生物强化工艺:通过混凝过程进行预处理后,投加嗜盐菌进行生物强化考察盐度变化对系统降解有机物的影响以及污泥性状的变化情况.结果表明,当废水中氯离子浓度达到驯化目标10 g/L时,系统对COD的去除率仍稳定在85％左右;以没有投加嗜盐菌的反应器为对照组,在进水COD平均浓度为550 mg/L左右,氯离子浓度由12 g/L增至21 g/L时,对照组COD平均去除率由82％降至60％以下,而投加了嗜盐菌的反应器(投加组)则仍保持在85％以上;此外,盐度的变化同时影响污泥的活性及其沉降性能,随着盐度增大,两组中的污泥活性均有所降低,但投加组的污泥活性相对较高,其污泥的沉降时间和污泥体积指数(sludge volume in-dex,SVI)值也较低.采用本工艺处理环氧树脂高盐废水,使得生物处理过程能够长期稳定运行,且能够保持较高的耐盐度和COD去除率.     

载钯螯合树脂的制备、表征及其降解多溴联苯醚的初步研究

以聚丙烯醛-异烟酰腙螯合树脂为高分子载体, 利用其活性基团对钯的选择性富集分离性能, 将金属元素钯键合到高分子载体上, 制备一种含钯树脂材料(树脂1), 并进一步原位还原得到还原态的载钯树脂(树脂2)。利用红外光谱、扫描电镜和X射线衍射等对以上2种含钯树脂材料进行了分析表征,并考察了它们对持久性有机污染物(POPs)多溴联苯醚(PBDEs)的脱溴降解性能。结果表明,2种树脂对BDE₂₀₉均有降解活性, 其中树脂1的降解性能比树脂2的降解性能要高, 树脂中钯的氧化形态可能对BDE₂₀₉的催化降解起主要作用。     

树脂吸附-Fenton试剂氧化法处理水杨醛生产废水

采用树脂吸附-Fenton试剂氧化法处理水杨醛生产废水。XF-01树脂和XF-02树脂静态吸附水杨醛生产废水时,COD去除率均在85％以上,挥发酚去除率均高于90％。XF-02树脂对水杨醛生产废水的处理效果更佳。动态吸附随废水流量增大,吸附出水的COD和挥发酚质量浓度均增加。适宜的废水流量为15BV,树脂的最佳脱附温度为80℃。在连续4批的吸附-脱附实验中,吸附出水的平均COD约为1200mg／L,平均挥发酚质量浓度小于10mg／L。在Fenton试剂氧化中,铁屑和铁粉的催化效果差别很小,都好于FeSO4·7H2O。以铁屑为催化剂、H2O2溶液加入量为1％时,氧化出水的COD小于150mg／L,挥发酚质量浓度小于0．5mg／L。     

A miniature stainless steel net dumbbell-shaped stir-bar for the extraction of phthalate esters in instant noodle and rice soup samples

Abstract

This work reports the development of a very-simple-to-construct stir-bar extraction device so called “a dumbbell-shaped stainless steel stir-bar.” The extraction device was assembled from a rolled up stainless steel net filled with an XAD-2 sorbent and a metal rod to allow the use of a magnetic stirrer during extraction. The dumbbell-shaped stainless steel stir-bar was used to extract diethyl phthalate (DEP), dibutyl phthalate (DBP), and di(2-ethylhexyl) phthalate (DEHP) before analysis by a gas chromatograph equipped with an electron capture detector (GD-ECD). Under the optimal conditions, the developed method provided a good linearity from 10.0 to 1,000.0?ng mL^?1 for all three compounds. Limits of detection and limits of quantification were 9.37?±?0.29?ng mL^?1 and 31.22?±?0.95?ng mL^?1 for DEP, 5.73?±?0.31?ng mL^?1 and 19.1?±?1.0?ng mL^?1 for DBP and 3.30?±?0.06?ng mL^?1 and 11.0?±?0.19?ng mL^?1 for DEHP, respectively. Good recoveries in the range of 81.89?±?0.17 to 109.5?±?2.0% were achieved when the method was used to extract phthalate esters in five instant noodle and two rice soup samples.     

Nitrogen removal efficiencies and microbial communities in full-scale IFAS and MBBR municipal wastewater treatment plants at high COD:N ratio

• Two IFAS and two MBBR full-scale systems (high COD:N ratio 8:1) were characterized. • High specific surface area carriers grew and retained slow-growing nitrifiers. • High TN removal is related to high SRT and low DO concentration in anoxic tanks. The relative locations of AOB, NOB, and DNB were examined for three different kinds of carriers in two types of hybrid biofilm process configurations: integrated fixed-film activated sludge (IFAS) and moving bed biofilm reactor (MBBR) processes. IFAS water resource recovery facilities (WRRFs) used Anodkalness^TM K1 carriers (KC) at Broomfield, Colorado, USA and polypropylene resin carriers (RC) at Fukuoka, Japan, while MBBR WRRFs used KC carriers at South Adams County, Colorado, USA and sponge carriers (SC) at Saga, Japan. Influent COD to N ratios ranged from 8:1 to 15:1. The COD and BOD removal efficiencies were high (96%–98%); NH₄⁺-N and TN removal efficiencies were more varied at 72%–98% and 64%–77%, respectively. The extent of TN removal was higher at high SRT, high COD:N ratio and low DO concentration in the anoxic tank. In IFAS, RC with high specific surface area (SSA) maintained higher AOB population than KC. Sponge carriers with high SSA maintained higher overall bacteria population than KC in MBBR systems. However, the DNB were not more abundant in high SSA carriers. The diversity of AOB, NOB, and DNB was fairly similar in different carriers. Nitrosomonas sp. dominated over Nitrosospira sp. while denitrifying bacteria included Rhodobacter sp., Sulfuritalea sp., Rubrivivax sp., Paracoccus sp., and Pseudomonas sp. The results from this work suggest that high SRT, high COD:N ratio, low DO concentration in anoxic tanks, and carriers with greater surface area may be recommended for high COD, BOD and TN removal in WRRFs with IFAS and MBBR systems.     

改性三聚氰胺甲醛树脂的合成及性能研究

研究了反应物配比、反应时间、反应温度、ＰＨ值对丙烯酰胺改性三聚氰胺甲醛树脂絮凝效果的影响，实验结果表明絮凝效果最佳的合成反应条件为三聚氰胺／甲醛／丙烯酰胺（质量比）＝１／５（２－３），反应温度为７０℃，反应时间为４ｈ，ＰＨ值为９．０左右。     

野外便携净水器净水消毒工艺试验研究

野外便携净水器应具杀菌消毒效率高、净水时间短、使用寿命长、操作方便等功能使用要求。通过试验考察了三碘树脂和载银活性炭两种不同净水消毒工艺流程对原水处理效果。结果表明：三碘树脂材料比载银活性炭材料具有灭菌效果好、反应接触时间短、使用时间长等优势，是一类具有良好军事应用价值的野外便携净水器的净水消毒材料。     

大孔树脂对邻苯二甲酸的吸附研究

研究了XDA-200大孔树脂对水溶液中邻苯二甲酸的吸附。结果表明XDA-200树脂对水溶液中的邻苯二甲酸吸附速度很快，30min内基本达到平衡，其后达到完全平衡的吸附进程非常缓慢。树脂对邻苯二甲酸的吸附量随质量浓度增加而增加。pH值降低，有利于邻苯二甲酸在溶液中以分子态存在，易于树脂吸附。邻苯二甲酸的吸附均满足Freundlich和Langmiur等温吸附方程。泄漏点与进水浓度和流速均有很大关系。     

用螯合树脂研究光解作用对水中铝形态的影响

本文对用螯合树脂分离水中无机铝和有机铝的方法、螯合树脂的制备及其对无机铝的交换进行了探讨。结果表明,水体中的有机铝在紫外光照射下能分解为无机铝,其分解速度随光照时间的增加而增加。由于无机单聚体铝对鱼类有致毒作用,因此,光解作用的结果使水体中铝的毒性增加。