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1.
李艳春  彭茹冰  王文富  张伟锋 《科技信息》2010,(35):335-335,364
氮是造成水体富营养化的重要污染物质之一,随着污染物排放标准对氮排放的日益重视,传统的生物脱氮方法得到了进一步发展,目前多种脱氮工艺组合或通过理论创新而开辟的新型生物脱氮路线成为新的发展应用方向。在高浓度氨氮废水处理方面,短程硝化、硝化-反硝化、同步硝化反硝化和厌氧氨氧化工艺越来越受到重视,提供了可能有效解决此类废水污染的途径。  相似文献   

2.
DO对MBBR同步硝化反硝化生物脱氮影响研究   总被引:25,自引:0,他引:25  
研究了移动床生物膜反应器(MBBR)同步硝化反硝化生物脱氮城市污水处理工艺.试验结果表明,当溶解氧(DO)质量浓度为2 mg.L-1、水力停留时间为8 h、悬浮填料填充率为50%时,MBBR工艺可通过同步硝化反硝化实现90%以上的脱氮效果.生物膜内DO质量浓度梯度造成好氧和缺氧区是实现同步硝化和反硝化的关键.该工艺能在同一个反应器中实现同时硝化和反硝化,并达到两个过程的动力学平衡,大大简化了生物法脱氮的工艺流程,提高了生物脱氮的效率,并节省投资.  相似文献   

3.
通过试验探讨了RNB 11芽孢杆菌在炼油废水深度处理脱氮过程中的生理特性,考察了以该芽孢杆菌为优势菌的生物膜在生物碳滤塔脱氮中的脱氮机理、脱氮效率及其环境影响因素。结果表明,芽孢杆菌主要进行亚硝化脱氮,在氨氮进水浓度25~70mg/L范围内,氨氮去除量与进水氨氮浓度成正比,氨氮的去除率稳定在58%~69%。  相似文献   

4.
为提高耐低温异养硝化-好氧反硝化菌株Pseudomonas fluorescent sp.Z03在低碳氮比条件下的脱氮能力,采用液相还原法制备了生物炭负载纳米零价铁复合材料nZVI-BC700.结果表明:在初始氨氮浓度为50 mg/L的情况下,nZVI投加量为0.2 g/L时,nZVI-8BC700耦合体系的最适pH为6.8~7.0,nZVI-8BC700可以有效提高微生物(Z03)的脱氮效率,在72 h内氨氮去除率提高至62.1%,相同条件下,比单独Z03的脱氮效率提高21.1%.推测达到这种结果可能是因为nZVI-8BC700为生物脱氮过程提供了电子供体,并提高了相关脱氮酶的活性,在还原和吸附共同作用下完成了水体氨氮的去除.  相似文献   

5.
吴岩  任相浩  寇莹莹  成宇 《科学技术与工程》2020,20(25):10544-10549
依托传统A/O工艺,采用短程硝化-反硝化处理人工高浓度氨氮废水,并投加新型复合微生物菌剂BMc-1强化废水处理效果,研究菌剂对污水脱氮的强化效果并分析对功能菌带来的变化。结果表明,投加菌剂后可以强化脱氮性能,实验组氨氮、总氮(TN)去除率达98.8%、82.0%,比较对照组氨氮、TN去除率97.3%、75.5%,分别提高1.7%、6.5%。16sRNA测序结果表明,投加菌剂使得活性污泥中微生物量、丰度以及多样性提高,菌剂对系统原微生物环境稳定性无影响,系统中Proteobacteria、Bacteroidetes、Chloroflexi为优势门未改变。投加菌剂后主要反硝化菌Thauera和氨氧化菌Nitrosomonas数量稳定,Pseudomonas、Thiopseudomonas、Terrimonas、Nitrosomonas脱氮功能菌占比提升。检测出Acinetobacter、Pedobacter等原系统不存在的脱氮相关功能菌。实验结果表明复合菌剂BMc-1具有强化生物工艺脱氮能力的作用。  相似文献   

6.
采用改良而成的OGO工艺技术,以试验配水模拟城市生活污水,研究了OGO系统的脱氮效果,通过分析反应器各反应区的脱氮效果,并结合OGO系统脱氮效果观察系统中活性污泥絮体特性,研究分析了OGO系统的脱氮机理.试验结果表明,在进水总氮(TN)和氨氮(NH4 -N)分别为31.15~42.26 mg/L和27.53~38.58 mg/L的条件下,OGO系统对总氮和氨氮的平均去除率分别可达74.31%和83.75%.反应器外环脱氮方式为同时硝化反硝化(SND)脱氮,其脱氮量占反应器脱氮总量的80.48%,OGO工艺对氮素的生物去除绝大部分是通过同时硝化反硝化来实现的;同时硝化反硝化的宏观分区理论和微环境理论均适用于OGO系统.  相似文献   

7.
张蕾 《科技资讯》2011,(27):151-152
本文以溶解氧为控制因素,利用低溶解氧实现了短程硝化生物脱氮,研究并验证了低溶解氧条件下短程硝化过程的稳定性。试验结果表明,在短程硝化建立起来后,无论是降低系统进水氨氮浓度,还是短期内提高溶解氧浓度对短程硝化都没有太大影响,低溶解氧下系统短程硝化过程具有长久的稳定性。  相似文献   

8.
微生物诱导碳酸钙沉淀过程是基于微生物产生脲酶而发生的。因此脲酶是影响该过程的重要因素。为了改善微生物加固尾砂的效果,考虑脲酶抑制剂能有效抑制脲酶活性、延缓尿素水解的作用,本文通过在微生物加固尾砂试验过程中引入了不同掺量的脲酶抑制剂,并对加固后的尾砂柱体进行宏观力学试验与微细观检测,系统分析了脲酶抑制剂对微生物加固尾砂的效果。结果表明:适量的脲酶抑制剂可较大程度地延长巴氏芽孢杆菌迟滞期,可改善碳酸钙沉淀分布的均匀性,可提升微生物固化后尾砂试样的力学性能。其中,脲酶抑制剂的掺量为0.1%时,砂柱试样具有明显的剪切破坏模式,其剪切峰增长13.26%,有效黏聚力增长11.82%,有效内摩擦角增长6.85%,碳酸钙生成率同比增长了34.17%,孔隙率降低了46.90%。  相似文献   

9.
HRT和载体对一体化生物膜反应器脱氮除磷效果的影响   总被引:7,自引:0,他引:7  
根据生物脱氮除磷原理,设计了一体化生物膜反应器,用于生活污水的处理。在一体化生物膜反应器处理生活污水连续运行基础上研究水力停留时间(HRT)和载体对反应器脱氮除磷效果的影响,同时通过分析微生物群落变化对系统脱氮过程进行探讨。试验结果表明:载体特性对反应器脱氮除磷效果影响显著;HRT为9 h时,载体B 4反应器总氮去除率为68.9%;好氧区HRT是限制系统脱氮效果的主要因素。由于载体的作用反应器好氧区存在着好氧缺氧微环境的交替,从而实现了好氧区同步硝化反硝化的脱氮过程。  相似文献   

10.
根据生物脱氮除磷原理,设计了一体化生物膜反应器,用于生活污水的处理。在一体化生物膜反应器处理生活污水连续运行基础上研究水力停留时间(HRT)和载体对反应器脱氮除磷效果的影响,同时通过分析微生物群落变化对系统脱氮过程进行探讨。试验结果表明:载体特性对反应器脱氮除磷效果影响显著;HRT为9h时,载体B4反应器总氮去除率为68.9%;好氧区HRT是限制系统脱氮效果的主要因素。由于载体的作用反应器好氧区存在着好氧缺氧微环境的交替,从而实现了好氧区同步硝化反硝化的脱氮过程。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

15.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

19.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

20.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

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