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关键词： Membrane distillation bioreactor   Anaerobic bioreactor   Domestic wastewater   Biogas   Volatile fatty acid   Submerged hollow fiber  

摘要： The effects of bioreactor temperatures and salinities of an anaerobic membrane distillation bioreactor (anMDBR) on the permeation performance and their potential recovery of bioresources were fully examined in this study. To the best of our knowledge, this is the first study of a lab-scale anMDBR process utilizing sub-merged hollow fiber membranes. The hybrid system utilizing both membrane distillation (MD) and anaerobic bioreactors achieved 99.99% inorganic salt rejection regardless the operation temperatures and high initial flux from (2-4 L m(-2) h(- 1)) at 45-65 degrees C. However, after 7-day operation, the flux dropped by 16-50% proportional to the bioreactor temperatures. It was found that the effects of bioreactor temperatures had strong impacts on both the permeation performance and fouling behavior while salinity had insignificant effect. A compact non-porous fouling layer was observed on the membrane surface from the bioreactor operated at 65 degrees C while only a few depositions was found on the membrane from 45 degrees C bioreactor. In the present study, the optimal anMDBR temperature was found to be 45 degrees C, showing a balanced biogas production and membrane permeation performance including less fouling formation. At this bioreactor temperature (45 degrees C), the biogas yield was 0.14 L/g CODremoval while maintaining a methane recovery of 42% in the biogas, similar recovery to those at bioreactor temperatures of 55 and 65 degrees C. The potential recovery of volatile fatty acids made anMDBR a more economically efficient system, in addition to its lower operation cost and smaller footprint compared with most other technologies for on-site wastewater treatment.

关键词： 厌氧生物反应器   沼气升级   pH   挥发性有机酸积累   氨氮抑制   碳酸盐缓冲体系  

摘要： 高负荷是升流式(Up-flow Anaerobic Sludge Bed, UASB)、内循环厌氧反应器(internal circulation, IC)和厌氧膜生物反应器(anaerobic membrane bioreactor, AnMBR)等厌氧生物反应器发展的趋势,也是实现"沼气升级(biogas upgrading)"的难点.挥发性有机酸(volatile fatty acids, VFAs)和溶解性无机碳(total inorganic carbon, TIC)既是厌氧消化必经的中间产物,又与氨氮等弱碱共同影响高负荷厌氧消化过程的pH变化,并决定着沼气中的甲烷含量.VFAs、TIC和氨氮构成的三元pH酸碱缓冲体系是高负荷厌氧消化"沼气升级"的关键操作条件.本文总结了高负荷厌氧消化过程中pH变化规律和影响,针对不同VFAs/氨氮关系的形成机制,分析了高负荷厌氧消化碳酸盐缓冲体系特征及其对沼气CH_4/CO_2构成的影响.以厌氧膜生物反应器为例,讨论了近年来基于pH在线监测和调控方法、理论模型方面的研究进展,同时对未来的重点研究方向提出展望,以期为今后的高负荷AnMBR研发提供参考.

关键词： Landfill   Microaerobic methane oxidation   Hypoxic methane oxidation   Leachate denitrification   Microbial community  

摘要： Managing nitrogen and carbon cycles in landfills is an environmental challenge. In this study, our purpose was to test two types of methane oxidation processes coupled to denitrification inside landfills: microaerobic and hypoxic methane oxidation coupled to denitrification (MAME-D and HYME-D). Leach bed bioreactors were designed and operated for >100 d with NO3- -N concentration ranging from 100 to 400 mg N/L During six runs of the leach bed bioreactor experiment, leach bed bioreactor 2 (MAME-D) reached 100% denitrification efficiency and the highest average specific denitrification rate of 20.36 mg N/(L.d) in run 5, while leach bed bioreactor 3 (HYME-D) achieved 75% denitrification efficiency and the highest average specific denitrification rate of 8.09 mg N/(L.d) in run 6. Subsequently, waste from leach bed bioreactors 1, 2, and 3 was inoculated into anaerobic bottles to run a batch experiment for 13 d. The total consumed methane, oxygen, and nitrate amounts in the microaerobic system with no methane and oxygen supplement were 2.33 2.38, and 2.04 mmol, respectively, which almost matched the theoretical equation of aerobic methane oxidation coupled to denitrification. In the hypoxic system, the total consumed methane and nitrate amounts were 023 and 0.41 mmol, respectively, the ratio of which dosely matched the HYME-D. In addition, via the diverse functional community analysis, methane oxidation in the microaerobic system was confirmed to be conducted by methanotrophs (i.e., Methylobacter and Methylomonas) using oxygen as an electron acceptor. Subsequently, the generated organic compounds could support denitrifiers (i.e., Methylophilaceae) to complete denitrification. In the hypoxic system, Methylomonas and Methylobacter utilized nitrate as a direct electron acceptor to oxidize methane. The two landfill processes characterized here will expand our understanding of the environmental role of methanotrophs and methylotrophs in both carbon and nitrogen cycles. (C) 201

关键词： Recalcitrant compounds   Tannins removal   Non-sterile conditions   Fungal reactor   Biomolecular analyses  

摘要： Tannins are polyphenolic compounds produced by plants that are used in the vegetable tanning of leather at industrial scale. Quebracho tannin and Tara tannin are intensively used by the tanning industry and are two of the most recalcitrant compounds that can be found in tannery wastewaters. In this study two reactors fed with Quebracho tannin and Tara tannin, respectively, were inoculated with polyurethane foam cubes colonized with a fungal strain biofilm of Aspergillus tubingensis MUT 990. A stable biofilm was maintained in the reactor fed with Quebracho tannin during 180 days of operation. Instead, biofilm got detached from the foam cubes during the start-up of the reactor fed with Tara tannin and a bacterial-based suspended culture was developed and preserved along the operational period (226 days). Soluble chemical oxygen demand removals up to 53% and 90% and maximum elimination capacities of 9.1 g sCOD m(-3) h(-1) and 37.9 g sCOD m(-3) h(-1) of Quebracho and Tara tannins, respectively, were achieved in the reactors without the addition of co-substrates. Next generation sequencing analysis for bacteria and fungi showed that a fungal consortium was developed in the reactor fed with Quebracho tannin while fungi were outcompeted by bacteria in the reactor fed with Tara tannin. Furthermore, Quebracho and Tara tannins were successfully co-treated in a single reactor where both fungi and bacteria were preserved.

关键词： 膜生物反应器-超低压纳滤系统(MBR-DF)   溶解性有机物   三维荧光   17-β雌二醇  

摘要： 针对再生水的高品质化和污泥的减量化问题,构建一套膜生物反应器-超低压纳滤组合工艺(MBR-DF)中试装置,以零排泥的方式运行处理城镇污水,同时建立一套传统活性污泥处理工艺(CAS),进水COD及NH_4^+-N、TN、TP浓度分别为87.0~165.7、14.0~31.0、14.2~32.4和2.5~3.3 mgL。结果表明:浓水零排放MBR-DF系统对COD、NH_4^+-N和PO_4^(3-)具有较好的去除效果,去除率分别为95.7%、99.0%和68.5%。总溶解固体(TDS)和HCO_3^-的去除率分别为13.5%和31.1%,并能有效地降低出水总硬度。DF膜对PO_4^(3-)和SO_4^(2-)具有明显的截留作用,对NO_3^-截留效果较差,对HCO_3^-无截留作用。进水溶解性有机物(DOM)经MBR-DF后,出水中仅剩少量的类色氨酸类物质,且MBR-DF系统对进水DOM的UV_(254)消减率达到94.9%,对DOC的去除率在98.0%以上,出水DOM的腐殖质向非腐殖质转化的程度较高。MBR-DF系统和CAS系统对17-β雌二醇(E2)的去除率分别为99.9%和70.8%,MBR-DF系统可有效降低出水回用过程中存在的健康隐患。

关键词： energy saving   membrane bioreactor (MBR)   peak flux operation  

摘要： Membrane bioreactors (MBRs) have the advantages of achieving excellent effluent quality, a small footprint and smooth operation and maintenance. On the other hand, its high energy consumption remains a critical challenge for MBR application. Japan Sewage Works Agency has conducted a series of joint researches with several private companies since 2012 and developed four kinds of energy-saving MBR systems. Based on the results of long-term pilot-scale demonstrations, specific energy consumption (SEC) per unit treated effluent volume was calculated for each MBR system, resulting in all systems achieving SEC of 0.4 kWh/m(3) or less. To meet an additional requirement for expanding MBR application, it is also necessary to establish the applicability of MBR systems to combined sewer systems, suffering from occasional inflow fluctuation caused by rainfall. The capability of temporary higher flux operation during and after rainy weather was also demonstrated with three of the four developed systems.

关键词： 烟草科学   烤烟   发酵条件优化   拮抗细菌   移栽期   生物反应器   种植密度   史宏   筛选鉴定   烟叶产质量  

关键词： 厌氧膜生物反应器(AnMBR)   废水处理   高浓度有机废水  

摘要： 目前厌氧膜生物处理技术被认为是处理高浓度有机废水的研究热点之一,它结合了厌氧生物处理与膜过滤系统,从而具有运营成本低、易于管理控制及剩余污泥产率少等优点。但是,也面临着诸如盐度积聚,抑制物质和膜污染等挑战。本文综述了厌氧膜生物反应器的基本原理和构造以及相关的影响因素,为高浓度有机废水的处理提供相关建议。

关键词： 生物反应器   烟草   虾青素合成酶   植物   微藻   酵母  

摘要： 为揭示不同真核生物源虾青素合成酶在烟草中的异源表达生物活性特征,明确开发虾青素烟草生物反应器的关键分子基础,本研究对夏侧金盏花(Adonis aestivalis)、雨生红球藻(Haematococcus pluvialis)及红发夫酵母(Xanthophyllomyces dendrorhous)3种真核生物源虾青素合成酶基因进行了密码子优化合成及表达载体构建,通过农杆菌介导的瞬时表达和稳定表达试验比较了其在烟草中合成虾青素的活性差异。结果表明,3种来源的虾青素合成酶基因均能在烟草中表达,但是仅夏侧金盏花和雨生红球藻来源的合成酶能在烟草中特异合成虾青素,且夏侧金盏花虾青素合成酶的活性最高。此外,稳定表达体系优于瞬时表达体系,能准确展示不同虾青素合成酶的活性差异。本研究为真核生物源虾青素合成酶在烟草生物反应器中的应用提供了重要基础。

关键词： 自然科学学报   黑龙江大学   难降解有机废水   废水生物处理   中国土木工程学会   生物反应器   哈尔滨工业大学   分子印迹聚合物  

摘要： 丁杰(DING Jie)哈尔滨工业大学环境学院教授、博士生导师。国际水协会IWA会员、中国土木工程学会会员。教育部“新世纪优秀人才支持计划”入选者。以废水生物处理及资源化与能源化为主要研究方向,开展了污水梯级利用规模化生物产氢及系统耦合的关键技术研究,突破了污染物完全矿化的终极目标,实现了有机废水的高值能源化;运用废水酸化原理和方法开发新工艺并探索工艺调控对策,大幅度提高了难降解有机废水的处理能力和处理水平,形成针对废水特征的集成技术和成套设备,并应用于实际废水处理工程;开展基于数值模拟技术的生物反应器的研发工作,建立了气-固-液三相耦合模型,优化反应器结构和设计参数,研究成果可应用于生物反应器的系统放大与优化;针对高浓度难降解废水深度处理的问题,开展了基于磁性分子印迹聚合物的水中微量污染物的检测和去除技术研究。