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关键词： Wastewater treatment   Anaerobic osmotic membrane bioreactors   Extracellular polymeric substances   Salt accumulation   Membrane fouling  

摘要： Anaerobic osmotic membrane bioreactors (AnOMBRs) have attracted much attention in recent years due to their ability to produce high-quality effluent with low energy demand. Here, the performance of a thin film composite (TFC) forward osmosis (FO) membrane in an AnOMBR system is evaluated, and the key membrane foulants are examined by analyzing the characteristics of the mixed liquor and the fouling layer. As the experiment progressed, the water flux declined due to membrane fouling and salt accumulation in the bioreactor, and reached approximately 3.5 LMH by the end of each operating cycle where membrane cleaning was adopted. The conductivity increased from 3.3 mS/cm to 23.6 mS/cm over the 28-day treatment. The contaminant rejection rates of total organic carbon, total phosphorous and ammonia-nitrogen were more than 93%, 98% and 60%, respectively. Results also suggested that extracellular polymeric substances (EPS) was the major contributor to membrane fouling, and the increase of EPS in the mixed liquor with salinity was primarily composed of polysaccharides. The comprehensive characterization of the fouling layer via X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy and confocal laser scanning microcopy (CLSM) revealed the coexistence of biofouling and organic fouling. The CLSM images further demonstrated the prevalence of ? polysaccharides, proteins and microorganisms on the fouled TFC FO membrane surface. In addition, the flow cytometric analysis indicated that the foulant sample was ?bacterial viable?, the large number of bacteria in suspension (96.61% live cells) maybe corresponded to the high EPS content in the bulk mixed liquor.

关键词： MBR   污水处理   膜污染   膜清洗   防治  

摘要： 膜生物反应器在应用过程中,存在膜污染后水质降低且影响处理效率的问题。为此,文章首先分析了膜污染的形成机理和影响因素,提出以改变膜的材料属性、合液中投加填料、优化操作条件三个方面的防治措施,以求找出能够有效控制膜污染的方法。

关键词： 美国紫薇   微型扦插   基质   激素   成活率   根生长量  

摘要： 为提高美国紫薇新品种嫩枝扦插育苗成效,在陕西省苗木繁育中心,对由泥炭、珍珠岩、炉渣、细椰糠等配置的不同基质,IAB、NAA、ABT1号等激素及其不同浓度(50、100、200 mg·L^(-1))对美国紫薇“红火箭”“红火球”“红叶”品种嫩枝微型扦插成活率、幼苗根数、根长等影响进行了研究,结果表明:美国紫薇嫩枝扦插要求温度25~35℃,湿度80%以上,插穗长度2~4 cm,保留2片全叶;红火球、红火箭扦插最适宜的基质配比为泥炭∶珍珠岩1∶2,红叶扦插适宜基质配比为泥炭∶珍珠岩∶炉渣1∶1∶1;激素以ABT1号生根粉100 mg·L^(-1)处理1 h最佳。

关键词： 污泥处理   二级处理   生物反应器   处理成本   污水污泥   澄清器   澄清池   污泥量  

摘要： 污泥主要是从液体污水中除去较少量的固体物质。初级污泥包括在初级澄清器中初级处理期间除去的可沉降固体。在二级澄清池中分离的二级污泥包括来自二级处理生物反应器的处理过的污水污泥。污泥处理方法的选择取决于产生的污泥量,并比较可用处置方案所需的处理成本。

关键词： 抗盐聚合物采出水   微生物反应器   污水处理   水力停留时间  

摘要： 以大庆油田第一采油厂某抗盐聚合物污水处理站原水为研究对象,探索微生物法处理抗盐聚合物采出水的适应性。室内构建“四级厌氧-两级缺氧-好氧-沉淀”复合生物反应器进行试验,研究不同水力停留时间下复合生物反应器处理效能。试验可知复合微生物反应器能够有效降低抗盐聚合物采出水中含油量及悬浮固体,且随装置水力停留时间增加去除率显著升高。在水力停留时间16 h条件下,出水含油和悬浮固体质量浓度均小于20 mg/L,含油去除率达97.56%,悬浮固体去除率达93.24%,同时该反应器对于抗盐聚合物采出水中聚合物含量、COD含量及黏度均具备一定去除效果。试验结果表明,复合微生物反应器能够有效去除抗盐聚合物污水中污染物,微生物法在抗盐聚合物污水处理中具有巨大潜力。

关键词： 膜生物反应器式   现场检验   维护使用  

摘要： 以涠洲11-4A平台改造的生物接触氧化法生活污水处理装置为例,对海上平台生活污水处理系统、现场检验及维护使用进行介绍,旨在为海上平台生活污水处理装置的日常使用维护作引导,并启发新型设备的研发,促进对海洋生态环境的保护。

关键词： Sulfate-reducing bacteria   Metal precipitation   Bacterial community structure   Syntrophism  

摘要： The down flow structured bed bioreactor (DFSBR) was applied to treat synthetic acid mine drainage (AMD) to reduce sulfate, increase the pH and precipitate metals in solutions (Co, Cu, Fe, Mn, Ni and Zn) using vinasse as an electron donor for sulfate-reducing bacteria (SRB). DFSBR achieved sulfate removal efficiencies between 55 and 91%, removal of Co and Ni were obtained with efficiencies greater than 80%, while Fe, Zn, Cu and Mn were removed with average efficiencies of 70, 80, 73 and 60%, respectively. Sulfate reduction increased pH from moderately acidic to 6.7?7.5. Modelling data confirmed the experimental results and metal sulfide precipitation was the mainly responsible for metal removal. The main genera responsible for sulfate and metal reduction were Geobacter and Desulfovibrio while fermenters were Parabacteroides and Sulfurovum. Moreover, in syntrophism with SRB, they played an important role in the efficiency of metal and sulfate removal.

关键词： Bioenergy   Forward osmosis   MBR   Microbial community   OMBR  

摘要： Renewable energy, water conservation, and environmental protection are the most important challenges today. Osmotic membrane bioreactor (OMBR) is an innovative process showing superior performance in bioenergy production, eliminating contaminants, and low fouling tendency. However, salinity build-up is the main drawback of this process. Identifying the microbial community can improve the process in bioenergy production and contaminant treatment. This review aims to study the recent progress and challenges of OMBRs in contaminant removal, microbial communities and bioenergy production. OMBRs are widely reported to remove over 80% of total organic carbon, PO43-, NH4+ and emerging contaminants from wastewater. The most important microbial phyla for both hydrogen and methane production in OMBR are Firmicutes, Proteobacteria and Bacteroidetes. Firmicutes? dominance in anaerobic processes is considerably increased from usually 20% at the beginning to 80% under stable condition. Overall, OMBR process has great potential to be applied for simultaneous bioenergy production and wastewater treatment.

关键词： Magnesium   In vivo   Bioreactor   Ex vivo  

摘要： Traditional in vitro evaluation criteria of magnesium (Mg)-based stents cannot reflect the degradation process in vivo, due to the interdependence and interference between biodegradable properties and bioenvironment. The current direct and indirect evaluation approaches of in vitro biocompatibility do not have a hydrodynamic environment and vascular biological structure existing in vivo. Herein, we designed a vascular bioreactor to provide an ex vivo culture environment for vessels, which reveals the degradation behavior of Mg-Zn-Mn stent and the effect of its degradation on cells. We reported that rabbit carotid arteries could maintain native morphology and viability in the bioreactor under the best condition within a flow rate of 5.4 mL min(-1) and a culture time of one week. With this culture condition, Mg-Zn-Mn stents were implanted into the arteries in the bioreactors and compared with in vivo rabbit models. The arteries maintained cell survival in the bioreactor, but the cell attachment was absent on the stent struts, associated with a fast degradation. Conversely, the stents achieved a rapid and complete endothelialization in vivo for two weeks. This study could provide a correlation and difference of the degradation behavior and cellular response to the degradation of Mg-based stent between ex vivo and in vivo approaches.

关键词： Ganoderma lucidum   Mushroom biomass   Red hybrid tilapia   Liquid fermentation   Sustainable aquaculture   Landless food production  

摘要： Mushroom mycelial biomass is an alternative to unsustainable use of cash crops as feed in aquaculture systems. Lately, fish-feed mixtures enhanced with heterotrophic 1-m(2)-bioreactor-grown biomass from the mycelium of Ganoderma lucidum (MGL) were fed to red hybrid tilapia Oreochromis sp. (tilapia). MGL biomass had high protein (32.2%), carbohydrate (48.4%) and fibre (13.8%) content compared with other common fish-feed sources (fishmeal, soybean meal, rice bran and corn). Four experimental diets containing 0 (control), 5, 10 and 15 g/kg of MGL biomass respectively were randomly allocated to eight, 70-L tanks at 15 fish per tank with duplicate treatments. All diets were formulated to be isoenergetic (~ 19 kJ/g), and the fish were fed twice per day at 3% of their body weight ratio during the feeding trial, which lasted for 42 days. The utilization of 15 g/kg of MGL in the feeding trial resulted in 100% survival rate (SR), longer body length (> 1.7 cm) and higher (35 g) body weight gain (BWG) among tilapia compared with control (30 g) after 6 weeks. Surprisingly, the feed conversion ratio (FCR) of tilapia fed with 15 g/kg (1.13) treatment was significantly lower compared with control (1.98), indicating better quality feed. The specific growth rate (SGR) of tilapia at 15 g/kg MGL (2.14) indicated a significantly greater growth compared with control (1.28). Internally, the condition factor (CF: 1.85), hepatosomatic index (HSI: 2.47) and visceral somatic index (VSI: 11.06) yielded the most significant organosomatic indices for treated tilapia compared with control, resulting in superior yield and fish health. Blood analysis of MGL-treated tilapia showed that haemoglobin (HGB: 6.43 g/dl), packed cell volume (PCV: 35%), red blood cells (RBC: 2.47 x 10(6) mm(3)) and white blood cells (WBC: 1.64.3 x 10(5) mm(3)) were significantly increased (P < 0.05) at 5 g/kg. These findings warranted that high MGL biomass diets could enhance tilapia survival and growth performance and thus