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利用臭氧氧化实现复合生物反应器污泥减量 总被引：3，自引：0，他引：3
采用复合生物反应器,对应用臭氧氧化实现污泥减量进行了研究。2个相同的复合生物反应器平行运行,1个作为对照系统,1个作为氧化系统。反应器内装有半软性填料,投加量为10%。曝气池中悬浮污泥浓度为1 500 mg/L左右,生物膜浓度为2 000 mg/L左右。试验结果表明,随着臭氧氧化污泥比例的增加,污泥表观产率系数也随之降低,当臭氧投量为0.05 g O3/gSS,每天氧化的污泥分别为反应器内污泥的10%,20%,30%时,污泥表观产率系数分别减少28.2%,44.9%,75.8%。虽然随着污泥氧化比例的增大,氧化系统出水CODcr略有增加,但氧化系统仍能保持其生物处理能力,CODcr去除率在92%以上;2个系统之间氨氮的去除率相差不大,氧化系统的硝化能力基本没有受到臭氧氧化的影响。 相似文献
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We have shown that municipal wastewater and sewage sludge are contaminated by organotins. Here, we investigate the behaviour and fate of tributyltin (TBT) in laboratory-scale sewage sludge treatment at various conditions including both aerobic and anaerobic, and mesophilic and thermophilic. Organotins were determined by capillary GC-FPD. Fresh raw sewage sludge was stored in a tank that was connected to five chemostats maintained at different conditions. Raw sludge contained TBT, dibutyltin (DBT) and monobutyltin (MBT) residues in the range of 0·28 to 0·83 mg/kg (dry weight). The volumetric TBT concentration was 10·5 μg/litre in the influent, and ranged from 7·4 to 8·3 μg/litre in the effluent of the different chemostats. In the anaerobic mesophilic treatment, concentrations of TBT did not decrease with increasing sludge residence time, DBT increased and MBT showed no clear trend. The DBT increase is suggested to be due to leaching from the PVC walls of the chemostats, and not to degradation of TBT alone. The TBT reduction did not show significant differences between the mesophilic and thermophilic anaerobic fermentors. These findings indicate that the degradation of TBT during sludge treatment is only low under all conditions tested. 相似文献
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将1株产油淡水微藻——微拟球藻(Nannochloropsis sp.MASCC 11)分别接种到青岛市2家市政污水处理厂(STP)的尾水中,根据其生长、油脂产率和营养盐去除情况,评价了利用STP尾水培养微藻以生产富油的藻生物质同时深度净化尾水的可行性。结果表明,团岛污水处理厂(TD-STP)和李村河污水处理厂(LC-STP)尾水中无机氮和磷酸盐的浓度虽然远低于BG11培养基,但仍能支持微藻生长,而且以未经稀释的尾水更具优势,培养8 d后,藻生物量分别达到BG11培养基中生长微藻的65.23%和44.77%。STP尾水经稀释后处于营养盐缺乏状态,有利于藻细胞内脂质积累,但是油脂产率最大值(10.5 mg·L-1·d-1)仍出现在未经稀释的TD-STP尾水中,为未稀释LC-STP尾水的1.37倍。LC-STP尾水中微藻的油脂产率较低,可能与该处理厂接纳工业废水而在尾水中残留较多有害物质有关。在微藻的直接和间接作用下,TD-STP和LC-STP尾水中磷酸盐的去除率分别达到94.5%和100%;无机氮的去除率较低(分别为59.2%和45.4%),与尾水中初始N/P较高有关。上述结果表明,与接纳工业废水的污水厂相比,处理生活污水的污水厂所排尾水较适于培养产油微藻,能够实现产油微藻低耗培养与尾水深度净化相耦合。 相似文献
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利用新型间歇增氧垂直流人工湿地,揭示了不同进水N H4+-N浓度下盐度提升对湿地脱氮性能及微生物群落的影响.试验结果表明:间歇增氧垂直流人工湿地在盐胁迫下的脱氮性能明显优于传统垂直流人工湿地,高盐(2.0％ 盐度)对TN去除性能影响较大,对COD去除性能影响相对较小.进水NH4+-N浓度为40 mg/L时,当盐度由0％... 相似文献
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Ben Ameur W Ben Hassine S Eljarrat E El Megdiche Y Trabelsi S Hammami B Barceló D Driss MR 《Marine environmental research》2011,72(5):258-264
Concentrations of ten polybrominated diphenyl ethers (PBDEs) and eight methoxylated polybrominated diphenyl ethers (MeO-PBDEs) in mullet (Mugil cephalus) and sea bass (Dicentrarchus labrax) collected from the Bizerte Lagoon and the Mediterranean Sea were investigated. To the best of our knowledge, this is the first report of these compounds in marine fishes from Tunisia. The PBDE mean concentrations in fish from Bizerte Lagoon were 45.3 and 96.2 ng g(-1) lw respectively in mullet and sea bass, while the concentrations of these compounds in mullet and sea bass from Mediterranean Sea were 7.80 and 27.9 ng g(-1) lw respectively. MeO-PBDE concentrations in mullet and sea bass from Bizerte Lagoon ranged from 6.46 to 286 ng g(-1) lw and from 49.4 to 798 ng g(-1) lw respectively, while the concentrations of these compounds in mullet and sea bass from Mediterranean Sea ranged from 190 to 401 ng g(-1) lw and from 353 to 578 ng g(-1) lw respectively. The total PBDEs and total MeO-PBDEs concentration in fish from Bizerte Lagoon were similar or slightly lower than those reported for other species from other locations around the world. 相似文献
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已有的研究证明,固定化光合细菌对污水中有机污染物的处理效果优于分散的光合细菌。本文利用从海洋中筛选分离的海洋光合细菌,以海藻酸钠为海洋光合细菌固定化基质,蒙脱石纳米材料为固定化基质添加剂,研究了固定化海洋光合细菌处理生活污水的效用。研究表明,使用海藻酸钠为基质的固定化海洋光合细菌和以蒙脱石纳米材料为添加剂的固定化海洋光合细菌对生活污水中的氮、磷均具有一定的处理效率,前者对氨氮、总氮和总磷的处理率最高分别为87.68%,70.95%和71.90%。添加蒙脱石纳米材料为添加剂后的固定化海洋光合细菌的去除率则分别为91.30%,73.51%和84.88%。添加有纳米蒙脱石的固定化海洋光合细菌比没有添加的固定化海洋光合细菌的去除率高10%左右,而且两者对氮、磷的处理速率也有大幅度的提高,在12h左右即可将处理效率提高到60%~80%。在高浓度有机废水和高氮磷浓度的废水处理中具有较强优势,同时由于该方法使用固定化光合细菌的量较少,回收简单,对污水处理中的污泥减量化也有一定的贡献。 相似文献
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The chitosan–montmorillonite composites (CTS–MMT) were prepared by CTS in combination with Na-type montmorillonite (Na-MMT). The composites were characterized by X-ray diffraction and Fourier transform infrared spectroscopy. The effects of initial pH value of the solution, adsorbent dose, the mass ratio of CTS to Na-MMT, the adsorption temperature, and contact time on acid fuchsin (AF) removal efficiency were investigated. The results indicated that the CTS could be successfully intercalated into the interlayers of Na-MMT. With the increase in content of CTS, some of them may be distributed on the surfaces of the clay and the AF removal efficiency can reach 80.2% using CTS–MMT as adsorbent to treatment AF wastewater (the AF concentration 20?mg/L) under the condition of pH, 5; adsorbent dose, 5?g/L; the mass ratio of CTS to Na-MMT, 0.25:1; adsorption temperature, 40°C; and contact time, 90?min. Meanwhile, it was shown that the adsorption processes were better fitted by pseudo-second-order model and the Freundlich model. 相似文献
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西瓦湖及其邻近河流中双酚A的浓度分布 总被引：6，自引：0，他引：6
双酚A属于内分泌干扰物，已经被多个国家列入优先污染物名单。本文研究了西瓦湖及其邻近河流各环境介质中双酚A的浓度分布。结果表明．湖内表层水、悬浮物和沉积物中的双酚A浓度分别为6．7～37．8ng／L，0.4～3．5ng／L和3．4～50．5ng／g，西瓦湖北岸河流中双酚A的浓度则高得多，表层水、悬浮物和沉积物中的浓度分别为62．9—3035ng／L，2．5～457．7ng／L和10．5～365．7ng／g。水体和悬浮物中的双酚A浓度呈现北部站位最高，中部其次，西南角水闸附近最低的分布格局，说明其污染源主要来自北岸工业区的废水排放。沉积物中的双酚A浓度出现了中西部地区较高的反常现象，可能与该地区废泥渣的排放有关。与世界上其他地区相比．西瓦湖及其临近河流中双酚A的污染相当严重，其中河流中的双酚A浓度超过了生物效应的临界浓度，可能会对当地的多种生物造成危害。 相似文献
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PCR-DGGE解析阴离子交换膜生物反应器反硝化过程中微生物群落结构变化 总被引：3，自引：0，他引：3
通过扫描电镜和聚合酶链式反应-变性梯度凝胶电泳(PCR-DGGE)方法考察了进水NO3-浓度变化对阴离子交换膜生物反应器微生物种群结构的影响。研究结果表明,在进水NO3-浓度从47.01 mg/L逐渐增加到168.55 mg/L的过程中,出水中NO3--N浓度满足我国饮用水水质标准中小于10 mg/L的要求。电镜扫描图显示微生物的形态结构发生了很大变化。对不同阶段的样品进行PCR-DGGE图谱和相似系数分析,发现随着反应的持续进行,微生物种群结构发生了演替变化,证实污泥微生物生态能够迅速进行优胜劣汰的筛选,调整内部微生物种群结构,从而达到适应环境的目的。 相似文献
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本文研究碳氮(C/N)比变化对移动床生物膜反应器(MBBR)处理海水养殖废水性能的影响。结果表明,当C/N比从7∶1降至3∶1,出水COD浓度无明显变化,平均去除率保持在90%以上。C/N比的变化对脱氮过程有较大影响,当C/N比从7∶1降低至3∶1,NH+4-N去除率由89.51%±1.24%增至92.70%±1.08%,NO-2-N浓度由(4.84±0.50)mg/L降至0 mg/L,NO-3-N浓度由(0.47±0.29)mg/L升至(8.12±0.25)mg/L。C/N比的降低提高了比氨氧化速率、比亚硝酸盐氧化速率和与硝化相关的微生物酶活性,但降低了比耗氧速率、比硝酸盐还原速率、比亚硝酸盐还原速率、脱氢酶活性和与反硝化相关的微生物酶活性。松散型胞外聚合物和紧密型胞外聚合物的多糖含量随C/N比的降低而降低,说明在低COD条件下,多糖能够被微生物利用。微生物群落的丰富度和多样性随C/N比的降低而降低,硝化菌属(Nitrosomonas和Nitrospira)和反硝化菌属(Azoarcus、Comamonas、Hyphomicrobium、Paracoccus、Thauera、Devosia、Pseudomonas和Rhodanobacter)的相对丰度发生改变,从而影响MBBR脱氮性能。 相似文献
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Chemical oxygen demand (COD) is a practical parameter that is used to estimate the amount of organic pollutants in aqueous systems. It is generally used as a guideline to control the quality of waste treatment effluent globally and is a management tool to evaluate the total pollution load in the highly developed coastal regions of Korea. It is a preferred method because of the speed and simplicity of the analysis and because there are fewer instrumentation requirements. The Ministry of Oceans and Fisheries (MOF) of the Republic of Korea developed a standard procedure for the measurement of COD. It has been revised several times, and the most recent revision was made in 2013 (MOF 2013–230). In this study, we modified the standard COD measurement procedure (MOF 2013–230), especially the sample digestion apparatus, to enhance analytical efficiency for a large sample number (batch), which is called a Korea Institute of Ocean Science and Technology (KIOST) modified MOF 2013–230. We examined uncertainty related to each experimental step and optimized laboratory conditions to reduce such uncertainties. The detection limit and estimated expanded uncertainty related to the KIOST modified MOF 2013–230 was 0.18 and 0.11 mg O2/L at a 95% confidence level (k = 2), respectively. This study also provides several tips to maintain consistent COD measurements in seawater using the alkaline potassium permanganate method. 相似文献
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Hyo Jin Lee Sang Hee Hong Moonkoo Kim Sung Yong Ha Soon Mo An Won Joon Shim 《Ocean Science Journal》2011,46(2):95-103
Masan and Haengam Bays in Korea are highly polluted and semi-enclosed. Domestic and industrial effluents are directly or indirectly
discharged into the bays through sewage treatment plants (STP) and creeks. In this study, 15 dissolved sterol compounds were
determined in order to understand their sources and relative contribution. Freshwater samples were taken from 13 creeks and
at two STP sites on a monthly basis. Total dissolved sterol concentrations ranged from 993 to 4158 ng/L. The concentrations
of sterols in winter were higher than in summer. Among the sterols analyzed, cholesterol, β-sitosterol, coprostanol and cholestanone
were major compounds in creek water. Seawater samples were concurrently collected at 21 stations in Masan Bay. Total sterol
concentrations ranged 118–6,956 ng/L. Inner bay showed high concentrations of sterols in summer, while outer bay showed high
sterol concentrations in winter. Among the sterols, cholesterol, β-sitosterol and brassicasterol were major compounds in seawater.
In order to examine the contribution of urban sewage, the concentration of coprostanol and fecal sterol ratios were calculated.
Most of the creek water, inner bay and near STP outlet samples were affected by sewage. Terrestrial organic matters accounted
for a high proportion of dissolved organic matter origin. Fecal origins were relatively high in the inner bay areas and in
the STP outlet, while sterols of marine origin were high in the outer bay areas. 相似文献
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Comparative vitellogenic responses in three teleost species: extrapolation to in situ field studies. 总被引：5，自引：0，他引：5
Induction of vitellogenin (VTG) was compared among three teleostean species to determine their relative sensitivity of exposure to 17 beta-estradiol (E2). Japanese medaka (Oryzias latipes), sunshine bass (Morone saxatalis x Morone chrysops) and channel catfish (Ictalurus punctatus) were exposed to aqueous concentrations of E2 ranging from 10 to 100,000 ng/l for 21 days. Respective EC50 values for plasma VTG detected by western blot in medaka, catfish and bass were 200, 170 and 1560 ng E2/l. Since these EC50 values are based on VTG induction curves calculated relative to control values, they indicate differences in species' sensitivity to E2 exposure. Catfish and bass VTG responses obtained in laboratory exposures were compared to VTG responses previously observed with 21-day wastewater treatment plant effluent exposures. Plasma VTG induction in effluent-exposed fish ranged from 14 to 82% above reference values depending on species. Extrapolation of field responses with laboratory-exposed fish indicate catfish and bass were exposed to the equivalent of 27-240 ng E2/l in sewage effluent. 相似文献
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Sewage disposal is a major environmental issue in both developed and developing countries and removal of pollutants such as organic matter, nutrients, heavy metals and persistent organic compounds is required to protect the environment. Novel biological systems using constructed mangrove wetland and immobilized microalgal beads have been developed as alternative systems for treating different types of sewage and pollution at source. The feasibility and efficiency of constructed mangrove wetland to remove organic matter and nutrients from primary settled municipal sewage were demonstrated through a series of greenhouse experiments and a pilot-scale field trial. The treatment efficiency of constructed mangrove wetland was comparable to, or higher than, the conventional constructed wetland. An immobilized microalgal system was developed to remove toxic persistent pollutants from industrial wastewater. Pollutant-resistant microalgal species were selected for culture in domestic wastewater. The harvested biomass was immobilized in alginate beads. Bench-scale experiments showed the algal beads were effective in removing industrial pollutants such as heavy metals (e.g. Cu, Zn, Ni, Cr, etc.), organometallic compounds (e.g. tributyltin, TBT), and persistent organic compounds (e.g. polycyclic aromatic hydrocarbons, PAHs) through biosorption and biodegradation. The adsorbed metals could be recovered by desorption process, and the beads could be used repeatedly for many adsorption–desorption cycles. 相似文献
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Wastewater discharges affect the functioning of small temporarily open/closed estuaries (TOCEs) through two main mechanisms: (1) they can significantly change the water balance by altering the quantity of water inflows, and (2) they can significantly change the nutrient balance and hence the water quality. This study investigated the bio-physical responses of a typical, small TOCE on the east coast of South Africa, the Mhlanga Estuary. This estuary receives significant inflows of treated effluent from upstream wastewater treatment works. Water and nutrient budgets were used together with biological sampling to investigate changes in the functioning of the system. The increase in inflows due to the effluent discharges has significantly increased the mouth breaching frequency. Furthermore, when the mouth closes, the accumulation of nutrients leads to eutrophication and algal blooms. A grey water index, namely the proportion of effluent in the estuary and an indicator of the additional nutrient inputs into the estuary, reached high values (?50%) during low flow regimes and when the mouth was closed. In these hyper-eutrophic conditions (DIN and DIP concentrations up to 457 μM and 100 μM respectively), field measurements showed that algal blooms occurred within about 14 days following closure of the mouth (chlorophyll-a concentrations up to 375 mg chl-a m−3). Water and nutrient balance simulations for alternative scenarios suggest that further increases in wastewater discharges would result in more frequent breaching events and longer open mouth conditions, but the occurrence of hyper-eutrophic conditions would initially intensify despite more frequent openings. The study indicates how water and nutrient balance simulations can be used in the planning and impact assessment of wastewater treatment facilities. 相似文献
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Polychlorinated biphenyls (PCBs) are relict contaminants, while polybrominated diphenyl ethers (PBDEs) are in increasing use. Using sediment cores collected in the Strait of Georgia, we demonstrate that the surface sediment concentration of PCBs is largely determined by environmental processes, such as sediment accumulation and mixing rates, while that of PBDEs is strongly influenced by proximity to source. The Iona Island wastewater outfall appears to be a primary pathway for PBDEs. As well, Vancouver Harbour is highly contaminated with both classes of chemical. BDE-209, the main component of deca-BDE, is the dominant PBDE congener. Environmental debromination is not evident. Currently, the ranges of the surface concentration of PCBs and PBDEs are similar to one another, but that will change in the future, as the concentration of PBDEs continues to rise. The experience with PCBs suggests that if PBDEs were banned today, it would take decades for inorganic sediment to bury them. 相似文献