粉末活性炭对膜过滤性能的影响

向一体式膜生物反应器中投加粉末活性炭(PAC),可以显著提高膜的过滤性能,有效缓解膜的污染.研究结果表明:投加PAC的吸附作用减少了由于胞外聚合物(EPS)而引起的膜污染;膜表面PAC颗粒的存在减小了浓差极化层的厚度和水力边界层的厚度,提高了过滤物质的传递速率;膜表面形成的PAC层还可过滤微生物和胶体颗粒,减少了它们到达膜表面的数量.     

Broad range analysis of endocrine disruptors and pharmaceuticals using gas chromatography and liquid chromatography tandem mass spectrometry

Endocrine disrupting compounds (EDCs) and pharmaceuticals and personal care products (PPCPs) have been globally detected in impacted natural waters. The detection of trace quantities of EDCs and PPCPs in the environment is of great concern since some of these compounds have known physiological responses at low concentrations. EDCs can have a wide range of polarities, acidic and basic moieties, and exist in trace quantities, which often requires numerous complex extractions, large sample collection volumes, and multiple instrumental analyses. A comprehensive method has been developed allowing for the analysis of 58 potential EDCs in various water matrices using a single solid-phase extraction (SPE) of a 1 L sample with subsequent analyses using both gas chromatography and liquid chromatography, each coupled with tandem mass spectrometry (GC–MS/MS and LC–MS/MS). Instrument detection limits ranged between 0.12–7.5 pg with corresponding method reporting limits of 1–10 ng l⁻¹ in water. Recoveries for most compounds were between 50% and 112% with good reproducibility (RSD 6–22%).     

错流式动态膜-生物反应器中污泥活性的研究

应用错流式动态膜-生物反应器(CDMBR)对己内酰胺废水进行了180 d的实验,实验过程中测定反应器的膜出水和上清液的水质,并对污泥进行了耗氧呼吸速率测定.结果表明,上清液COD一直保持在100mg/L以下,而膜出水的则保持在50 mg/L以下,膜对上清液的COD去除率达50%,而对氮的去除没有贡献.可溶性细胞产物(SMP)在反应器内容易积累,停留足够的时间后能被生物降解.通过投加抑制剂测定耗氧呼吸速率,发现异养菌、硝化细菌和亚硝化细菌的活性由于F/M的降低和SMP积累受到一定的抑制,但不影响系统的处理效率.跨膜压力、膜面流速越大,通量衰减得也就越快.     

Pressurized liquid extraction of six tetracyclines from agricultural soils

Veterinary antibiotics used in agriculture can be introduced into the environment through land application of animal manure, accumulating in soils and groundwaters and posing a significant risk to human health and animal well-being. As the analysis of tetracyclines in soil is challenging due to their strong interaction with soil minerals and organic carbon, the objective of this study was to develop a reliable and reproducible method for quantitative analysis of chlortetracycline and oxytetracycline, and their respective metabolites in soils. A method based on pressurized liquid extraction (PLE) with in-cell clean-up was developed for the extraction of chlortetracycline and oxytetracycline and four likely metabolites from a set of four soils. Optimized conditions included a cell size of 22?mL, soil loading of 5?g, pH of 8.0, methanol:water ratio of 3:1, 50?°C, and two cycles. Soil extracts were analysed by high-performance liquid chromatography (HPLC) coupled with ion trap mass spectrometry (MS). Recoveries of seven tetracyclines from soil ranged from 41% to 110%. The limits of detection for tetracyclines were 0.08–0.3 µg g^?1 soil, and intra- and inter-day variation ranged from 0.12–0.34%. The proposed PLE method is suitable for quantification of tetracyclines in agricultural soils at typical concentrations expected in contaminated environments.     

Sorption of radiolabelled glyphosate on biochar aged in contrasting soils

Glyphosate mobility from terrestrial to aquatic environments has raised concerns about it. Utilizing soil’s inherent properties along with sorption properties of aged biochar, we hypothesized that selective application of biochar would be more effective in economic terms for glyphosate sorption on contrasting soils. To test this hypothesis, batch experiments and liquid scintillation counting for ¹⁴ Okada, E.; Costa, J. L.; Bedmar, F. Adsorption and mobility of glyphosate in different soils under no-till and conventional tillage. Geoderma 2016, 263, 78–85.[Crossref], [Web of Science ®] , [Google Scholar]C labeled glyphosate were used. The sorption behavior of glyphosate was examined in four contrasting Australian soil types (Oxisol, Vertisol, Entisol, and Inceptisol) amended with aged biochar to determine glyphosate concentrations by measuring ¹⁴ Okada, E.; Costa, J. L.; Bedmar, F. Adsorption and mobility of glyphosate in different soils under no-till and conventional tillage. Geoderma 2016, 263, 78–85.[Crossref], [Web of Science ®] , [Google Scholar]C activity using liquid scintillation counting. Freundlich parameters were calculated for soil-soil/biochar combinations. The pattern of glyphosate sorption was Oxisol?>?Vertisol?>?Entisol?>?Inceptisol. Oxisol adsorbed approximately five times more glyphosate compared with Inceptisol. Oxisol soil system adsorbed maximum amount of glyphosate principally due to the presence of iron-aluminum oxides exhibiting variable charges which got increased due to the presence of aged biochar. Considering all the soil/soil-biochar systems, Inceptisol soil system showed the least adsorption of glyphosate. A significant contribution of char was observed only in the Entisol soil system and the finding is valuable as char can be applied in Entisol soil systems to control glyphosate mobility.     

热电厂双膜法中水深度处理系统运行效果与问题分析

中水已成为热电厂的重要水源,其深度处理是影响电厂水处理系统的关键。为评估双膜法在电厂深度处理中的潜力与稳定性,考察了山东某热电厂石灰混凝-超滤(UF)-反渗透(RO)系统不同季节的处理效果及污染物去除特征与各工段贡献率。研究表明：双膜法对浊度、色度、电导、碱度、COD和TOC的去除率分别达95.82%、96.62%、96.73%、98.22%、96.42%和89.13%,在夏季严重膜污堵的条件下,也可保障产水达标,是一种有效的中水深度处理技术。预处理仅去除某些大分子腐殖酸类有机物、硬度类物质、悬浮物,富里酸类有机物、氮等其他溶解性物质主要由RO去除(去除率均60%),因此,存在膜结垢和污堵的风险。不同季节污染物浓度变化不显著,但夏季高温条件下微生物代谢和繁殖速率较高,荧光指数(fluorescence index, FI)大于2,生物指数(biological index, BIX)为1.2左右,这是夏季膜污堵爆发的关键原因。     

BPAC-UF对二级出水中抗生素抗性基因的去除及膜污染缓解机制

采用生物粉末活性炭(BPAC)-超滤(UF)组合工艺去除控制二级出水中抗生素抗性基因(ARGs),并对ARGs的去除和BPAC缓解膜污染机制进行了探讨。结果表明：与直接超滤工艺相比,组合工艺对水中四环素类抗性基因(tetA、tetW)、磺胺类抗性基因(sul Ⅰ、sul Ⅱ)以及溶解性有机碳(DOC)的去除效果均有较大的改善,这主要是由于BPAC对ARGs的吸附降解作用所致;水中16S rDNA、int Ⅰ 1和DOC含量与不同种类ARGs浓度具有显著相关性,强化上述指标的去除可有效促进ARGs的削减;在BPAC投加量较低时,组合工艺的膜比通量较直接UF有所提高,膜污染状况明显改善;直接UF时,膜污染状况与滤饼层过滤模型的拟合度最好,而组合工艺的膜污染状况与标准膜孔堵塞模型和滤饼层过滤模型拟合度均较好。BPAC-UF组合工艺是一种较好的去除ARGs的工艺。     

施粪肥土壤中抗生素的提取条件优化及残留特征

为确立高效的土壤抗生素提取条件,揭示施用粪肥土壤中抗生素的残留水平,分别采集江苏省常州市某养猪场新鲜猪粪样品6份、施用粪肥及无机肥水稻土壤样品各13份,对土壤抗生素提取液配比与超声提取时间进行筛选,利用高效液相色谱-串联质谱（HPLC-MS/MS）对生猪粪便和土壤中的四大类（四环素类、磺胺类、喹诺酮类和大环内脂类）15种抗生素含量进行检测分析。结果表明,最优提取条件选择为：提取液配比为甲醇：EDTA=1：1,超声提取时间为10 min,四环素类抗生素的加标回收率为73.2%~93.4%,磺胺类为81.2%~101.1%,喹诺酮类为106.3%~110.8%。该养猪场猪粪与施粪肥土壤中均未检测到大环内脂类抗生素,其余各类抗生素平均残留量从高到低排序分别为：猪粪中四环素类 > 磺胺类 > 喹诺酮类;施粪肥土壤中四环素类 > 喹诺酮类 > 磺胺类,四环素类是最主要的抗生素污染物,残留量分别为猪粪中1.9~12.5 mg·kg-1、施粪肥土壤中23.9~212.4 μg·kg-1;施无机肥土壤中未检测出抗生素,施粪肥土壤中的抗生素来源于生猪粪便。     

膜蒸馏处理页岩气井压裂返排液

页岩气压裂返排液的有效处理是页岩气开发急需解决的关键环保问题之一。针对新页HF-1井页岩气压裂返排液经预氧化结合湿式氧化（PO-WAO）工艺处理的出水COD不达标、含盐量高等技术难题,采用膜蒸馏处理技术对工艺的出水进行深度处理。通过膜蒸馏单因素和正交实验表明料液温度和冷凝温度对膜蒸馏处理效果影响较大,在料液温度、冷凝液温度、真空度、运行时间分别为80℃、8℃、0.090 MPa和60 min的最佳工艺条件下,膜通量可达1.750 L·（m2·h）-1,出水COD浓度为95.8 mg·L-1,出水水质可满足《污水综合排放标准》（GB 8978-1996）中一级排放的要求。膜蒸馏出水中电导率为63 μS·cm-1,氯化钠的质量浓度为1.168 0 mg·L-1,可有效降低处理后的压裂废液对周围土壤的盐碱化伤害。     

焚烧法处理环己酮生产中的皂化液

用环已烷氧化生产环已酮的生产过程中会产生大量的皂化液 ,它含有大量的有害物质 ,是一种难处理的高污染有机废水。某石化厂在借鉴造纸行业的黑液焚烧技术的基础上 ,采用焚烧法来处理皂化液 ,并得到副产蒸气和回收了碳酸钠 ,实现了皂化液的无害化与资源化 ,具有良好的社会效益、环境效益和经济效益 ,每处理 1t皂化液可盈利 10 0～ 2 0 0元