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31.
污水资源化、二氧化碳减排及微藻生物柴油是当前能源与环境领域的前沿课题。以下围绕污水及烟道气资源化培养产油微藻的培养体系,就藻种、营养条件、培养方式、培养环境及微藻生物反应器等影响产油微藻培养的因素研究进展进行了综述。在综述的基础上提出:由于微藻具有特殊营养方式,通过藻种筛选、微藻营养条件和培养环境的优化以及高效光生物反应器和生产工艺等的创新,可利用污水进行产油微藻生产,以获得生物柴油等高附加值产品,实现微藻生物能源、污水资源化处理和CO2减排三者高度耦合的产油微藻生产体系,从而减少微藻培养费用及污水处理费用,因此,该体系具有重要的环境、社会、经济价值和商业化应用前景。 相似文献
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光合细菌与酵母菌综合处理柠檬酸废水的初步研究 总被引:11,自引:0,他引:11
对应用光合细菌和酵母菌综合处理柠檬酸废水进行了初步研究,考察了各段工艺的处理效果。结果表明,第一步用热带假丝酵母处理后,CODCr去除率为13.6%,出水pH为7.5,沉淀的酵母泥干重得率7.0g/L,蛋白质含量47%;第二步用光合细菌处理后,CODCr去除率为58%,总去除率达63.7%,出水pH为9.6,絮凝沉淀的光合菌泥干重得率1.2g/L,蛋白质含量51%。 相似文献
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植物在水产养殖废水处理中的研究进展 总被引:4,自引:0,他引:4
植物在生长繁殖过程中能吸收利用、富集、吸附和固定水产养殖水体中的有机物、无机物和重金属,降低养殖水体中的TP、TN、TSS、COD和BOD。同时,植物在水体中可通过其发达的通气组织和根系传输氧气,为微生物和其他生物的代谢活动提供适宜的条件。选择合适的植物构建人工湿地,通过人工湿地中植物、微生物和基质的物理作用、化学作用和生物作用处理水产养殖废水,可建立循环的水产养殖模式。将植物应用于水产养殖废水的处理,是实现可持续发展的生态型水产养殖的基础。本文综述了近年来藻类和高等植物在水产养殖废水处理中的研究进展。 相似文献
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Aspergillus niger broth culture on wheat bran was assessed for olive wastewater (OW) hydrolysis in order to release hydroxytyrosol (HT). The enzyme profiles of this culture broth gave essentially (IU/L): 3000 β-glucosidase and 100 esterase. Hydrolysis activity of A. niger enzyme preparation was evaluated by using three substrates: raw OW, phenolic fraction extracted from OW by ethyl acetate and its corresponding exhausted fraction. Large amounts of free simple phenolics were released from exhausted fraction and raw OW after enzymatic treatment. HPLC analyses show that HT was the main phenolic compound. One step of ethyl acetate extraction of hydrolysed OW allowed the recovery of 0.8 g of HT per litre of OW. The antioxidant activity of extracts from OW and exhausted fraction, measured by DPPH method, was drastically enhanced after hydrolysis treatment. This study demonstrates that hydrolysed OW is a potential source of bioactive phenolic compounds with promising applications in food and pharmaceutical industries. 相似文献
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Two experimental high rate algal ponds (HRAPs) (1.5m2, 570 L per unit), each with a secondaryclarifier for algal biomass separation (0.025 m2,without recirculation), were fed with urban wastewaterfor a one-year period (June 1993 to July 1994). TheHRAPs were installed on the roof of the Department ofHydraulic, Coastal and Environmental Engineering ofthe Technical University of Catalonia, Barcelona,Spain (lat. 41° 24 42 N; long. 2° 742 E). Nitrogen removal efficiency and changes intotal nitrogen, total organic nitrogen,NH4
+-N, and oxidized nitrogen underdifferent hydraulic retention times (HRTs) werecompared. HRAP A was always operated at a higherHRT than HRAP B. Both HRAPs were subjected to thesame environmental conditions of solar radiation, airtemperature and influent water quality. Grab samplesof influent, effluent of the HRAP (mixed liquor) andfinal effluent from the clarifiers were taken once aweek. The annual average nitrogen removal was 73% forHRAP A, and 57% for HRAP B. Higher removal in HRAP Awas due to a lower inorganic nitrogen concentration inits effluent. Significant differences (p> 0.05) inthe relative proportions of nitrogen forms between thetwo HRAPs were observed only in autumn and winter.This was mainly because HRAP B did not achieve a highlevel of NH4
+-N removal by stripping andalgal uptake, as observed in HRAP A. NH4
+-Nstripping was the most important mechanism fornitrogen removal (mean efficiency of 47% and 32% inHRAP A and B, respectively) followed by algal uptake,and subsequent algal separation in the clarifiers(mean efficiency of 26% and 25% in HRAP A and Brespectively). The conclusion of this study is thatHRT determines both the nitrogen removal efficiencyand the distribution of nitrogen forms in the effluentof a HRAP. The nitrogen removal level can becontrolled through suitable HRT operating strategies.By operating at a HRT of 4 days in spring and summer,and 10 days in autumn and winter, nitrogenconcentration in the effluent of a HRAP system can bereduced to less than 15 mg L-1 N. 相似文献
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Abram F Enright AM O'Reilly J Botting CH Collins G O'Flaherty V 《Journal of applied microbiology》2011,110(6):1550-1560
Aims: The objective of this work was to provide functional evidence of key metabolic pathways important for anaerobic digestion processes through the identification of highly expressed proteins in a mixed anaerobic microbial consortium. Methods and Results: The microbial communities from an anaerobic industrial‐like wastewater treatment bioreactor were characterized using phylogenetic analyses and metaproteomics. Clone libraries indicated that the bacterial community in the bioreactor was diverse while the archaeal population was mainly composed of Methanocorpusculum‐like (76%) micro‐organisms. Three hundred and eighty‐eight reproducible protein spots were obtained on 2‐D gels, of which 70 were excised and 33 were identified. The putative functions of the proteins detected in the anaerobic bioreactor were related to cellular processes, including methanogenesis from CO2 and acetate, glycolysis and the pentose phosphate pathway. Metaproteomics also indicated, by protein assignment, the presence of specific micro‐organisms in the bioreactor. However, only a limited overlap was observed between the phylogenetic and metaproteomic analyses. Conclusions: This study provides some direct evidence of the microbial activities taking place during anaerobic digestion. Significance and Impact of Study: This study demonstrates metaproteomics as a useful tool to uncover key biochemical pathways underpinning specific anaerobic bioprocesses. 相似文献
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随着经济的发展和人口的增加,环境污染和水资源短缺已经成为不可避免的全球性问题。基于微藻的废水处理技术不仅可以净化废水、解决环境污染问题,还可以利用废水中的营养元素合成生物质,现如今这种技术已经受到越来越多的关注。为了进一步提高废水处理效果、降低废水处理成本,有必要了解微藻去除废水中营养物质和污染物的机理,开发下游低成本收获技术,提升微藻高价值副产物的生产。本文综述了微藻去除碳、氮、磷、重金属、抗生素和有机物的机理和影响因素,总结了微藻的不同收获方式和微藻生物质在各个领域的应用。最后,分析了不同微藻共培养体系和微藻固定化技术的优缺点,并展望了微藻废水处理技术未来的发展方向。 相似文献