短程硝化–厌氧氨氧化在实际垃圾渗滤液处理工程中的启动运行研究

针对新型脱氮工艺短程硝化?厌氧氨氧化(ANAMMOX)过程中亚硝氮难以稳定生成的难题, 设计水解酸化+UASB+好氧氧化的处理工艺, 应用于实际垃圾渗滤液处理工程。结果表明, 当进水氨氮浓度为610~1900 mg/L, C/N 比为1.8~3.5时, 在进水量为100 m³/d, 回流比为2:1, pH 值为7.5~8.0, DO为2.0 mg/L的调试条件下, O池发生短程硝化, 积累200 mg/L的亚硝氮, 积累率最高达78%。微生物DNA 检测发现, O池中AOB物种丰度是NOB的10倍以上。水解酸化池中存在COD、氨氮和总氮同时去除的现象, COD去除量不能满足全部总氮反硝化, 剩余的总氮通过厌氧氨氧化过程去除, 通过ANAMMOX反应去除的总氮占水解酸化池总氮去除量的35%~67%。在实际垃圾渗滤液处理工程中, 通过控制进水量、回流比、pH和溶解氧等条件, 成功地启动短程硝化?厌氧氨氧化工艺。     

短程硝化联合厌氧氨氧化处理垃圾渗滤液的启动

针对晚期垃圾渗滤液脱氮难的问题,采用短程硝化SBR联合厌氧氨氧化SBR工艺处理晚期垃圾渗滤液.短程硝化SBR经过50 d驯化和培养,其最终出水亚硝态氮质量浓度维持在500 mg/L左右,短程硝化率稳定在98％以上.为了消除过高亚硝态氮对厌氧氨氧化菌的抑制,压氧氨氧化SBR由传统的操作模式改为反应期间连续进水间歇沉淀和出水,其水力停留时间控制在20 h.在配水驯化期,进水亚硝质量浓度由60 mg/L提升至395 mg/L,总氮容积去除速率由0.10 kg/(m3·d)提升至0.75 kg/(m3·d);驯化结束后,逐步掺入渗滤液,在实验的第156天,进水中的亚硝态氮全部由好氧SBR的出水提供.研究结果表明:渗滤液中难降解的COD未对厌氧氨氧化菌产生抑制作用,少量的反硝化作用反而提高了系统总氮的去除率,此时,系统的总氮容积去除速率为0.76 kg/(m3·d),进水COD、亚硝态氮和氨氮质量浓度分别为295,390,295 mg/L,出水CDO、亚硝态氮和氨氮质量浓度分别为246,1.3和0.6 mg/L;在不添加任何碳源的条件下,总氮去除率达90％以上.     

准好氧填埋中不同区域反硝化类型分析

依据准好氧填埋的原理构建了准好氧填埋模拟试验装置。在填埋不同区域内布设渗滤液采样器定期进行渗滤液采样,并对渗滤液进行水质分析．分析指标包括COD、总氮、氨氮、硝态氮和亚硝态氯等。结果表明,由于受氧气浓度、氨氮浓度等的影响,不同区域内反硝化类型是不同的。好氧和准好氧区域内以好氧反硝化为主,厌氧区域内以传统厌氧反硝化为主,同时研究表明高浓度氨氮对好氧反硝化的抑制作用小于对传统厌氧反硝化的抑制。     

间歇式反应器亚硝化颗粒污泥培养试验

在间歇式反应器(SBR)中经20d驯化后,普通消化污泥具有亚硝化功能.然后接种厌氧颗粒污泥,控制反应条件:温度21 ℃,pH7.5～8.5,溶解氧(DO)质量浓度0.5～1.0 mg/L, 25 d后完成厌氧颗粒污泥向好氧亚硝化颗粒污泥的转变.好氧亚硝化颗粒污泥具有较好的脱氮效果,一个反应周期内氨氮(NH 4N)去除率达到91.4%,总氮(TN)去除率达到70.6%,亚硝酸盐氮与硝酸盐氮质量浓度比(ρ(NO-2N)/ρ(NO-3N))＞0.70,反应器实现了同步亚硝化反硝化.     

SBR工艺去除MAP沉淀后垃圾渗滤液中氨氮的实时控制

以经过UASB(上流式厌氧活性污泥床)+MAP(磷酸氨镁)处理后的垃圾渗滤液为试验用水,以氧化还原电位(ORP)、pH及溶解氧(DO)作为控制参数,系统研究了序批式活性污泥法(SBR)工艺生物脱氮过程的实时控制策略.结果表明:对于经过前处理的垃圾渗滤液,生物系统可以实现剩余氨氮的完全硝化-反硝化反应;在厌氧阶段,反硝化完全时,ORP曲线出现硝酸盐"膝点";在好氧阶段,硝化完全时,虽然pH曲线没有出现氨"谷点",但出现了转折点.因而,ORP和pH可分别作为反硝化及硝化反应控制参数.实时控制系统经2个月的稳定运行,总有机氮(TOC)和总氮(TN)的去除率分别达到了84 %和98 %.     

垃圾渗滤液厌氧氨氧化与反硝化的协同作用

采用有效容积为4.5 L的UASB生物反应器,对广东某垃圾填埋场的垃圾渗滤液配水进行厌氧氨氧化及反硝化.结果表明:在有机环境下,UASB反应器中可以实现厌氧氨氧化与反硝化的协同作用;在厌氧氨氧化活性稳定阶段(120天开始),氨氮和亚硝氮的平均去除率分别高达94.79%和98.17%;试验过程中,CODCr最高去除率可达51.68%,平均去除率为23.51%,相应的平均容积去除负荷为84.53 mg/(L·d).     

影响膜生物反应器同步硝化反硝化因素研究

通过控制膜生物反应器(MBR)中溶解氧(DO)浓度、碳氮比(C/N)、污泥浓度(MLSS)和水力停留时间(HRT)等摸索了实现同步硝化反硝化的工艺条件,同时对好氧反应器中实现同步硝化反硝化的机理进行了探讨.化学需氧量(COD)在250 mg/L左右,C/N为10～30∶1,MLSS为5 g/L,HRT为5.0 h,DO为0.6～0.8 mg/L时,总氮去除率达86.0%,取得了良好的总氮去除效果,表明由于好氧反应器中缺氧区的存在,控制好操作条件可以实现同步硝化反硝化.体系中氨氮、硝态氮浓度的变化与总氮去除的关系说明短程反硝化现象的存在,而且在实现同步硝化反硝化过程中发挥着重要的作用.     

曝气生物滤池前置反硝化去除COD、NH4+-N和总氮研究

为了满足出水总氮的要求,采用前置反硝化工艺完成脱氮过程。本文对曝气生物滤池前置反硝化工艺脱氮、去除COD的工艺性能进行研究,结果表明,系统对COD的去除主要发生在好氧柱,好氧柱出水基本比较稳定,系统出水COD浓度始终保持在50mg/L以下,COD去除率在83%以上;系统对氨氮有较高的去除效果,出水氨氮浓度低于4mg/L,去除率在80%以上;系统对总氮的去除率在40～50%之间。系统对总氮的去除率不高。     

A_2N-SBR双污泥反硝化生物除磷系统效能分析

采用生活污水和A2N-SBR工艺对反硝化除磷过程进行了研究.在进水COD浓度为325mg/L,磷浓度为9.1mg/L,氨氮浓度为65mg/L的条件下,出水氨氮浓度和磷浓度分别为3.3mg/L和0.17mg/L,氮和磷的去除率分别为95%和98%.进水C/N比对A2N-SBR反硝化除磷体系的除磷和脱氮效率都有重要影响,在进水C/N比为5时获得了最佳的脱氮和除磷效率;当C/N比小于5时,氮和磷的去除率都有大幅度的下降;当C/N比大于5时,氮的去除率未受到影响,而磷的去除率却有所下降.     

垃圾填埋层通风对循环渗滤液的硝化与反硝化作用

渗滤液循环回灌填埋层同时去除其中的碳、氮污染物的前提是层内必须存在好氧、兼性、厌氧混合代谢条件.通过对比间歇强制通风和强化自然通风这两种使填埋层内形成混合代谢条件的实验发现:两者均可使填埋层具有去除回灌渗滤液中化学耗氧量CODCr和氨氮的能力,间歇强制通风的去除负荷为CODCr165 g/(m2*d),氨氮7.5 g/(m2*d);强化自然通风则为CODCr480 g/(m2*d),氨氮16 g/(m2*d).填埋层对氨氮硝化形成的硝态氮的反硝化能力与回灌渗滤液中生物可利用碳BC与氨氮之比BC/N有关,当此比值大于4.5时,间歇强制通风填埋层可达到几乎完全的反硝化水平.但强化自然通风填埋层中,即使当BC/N大于7.5时,流出液中硝态氮仍大于50 mg/L,主要原因是层内存在持续有氧的区域,阻碍了对其的完全反硝化.     

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

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.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

Perspherical Approaches for Electrons in Atoms and Charged Excitons in Quantum Wells

Instead of following Fock’s expansion,we solve the Schrodinger equation for some quantum mechanical manybody systems such as electrons in atoms and charged excitons in quantum wells in a similar way in hyperspherical coordinates by expanding the wave functions into orthonormal complete basis sets of the hyperspherical hannonics(HHs)of hyperangles and generalized Laguerre polynomials(GLPs)of the hyperradius.This leads the equation to     

Advances in broadband wireless communications under high-mobility scenarios

Future mobile communication systems aim at providing very high data transmission rates, even in high-mobility scenarios such as high-speed wheel-track trains, maglev trains, highway vehicles, airplanes, guided missiles or spacecraft. A particularly important commercial application is the strong and increasing worldwide demand for high- speed broadband wireless communications （up to 574.8 km/ h test speeds or 380 km/h commercial speeds） in railways, providing data, voice and video services for applications such as onboard entertainment services to passengers, train control, train dispatch, train sensor status handling and sur- veillance. In such high-mobility scenarios, there are a number of communication challenges, including fast hand- over, location updating, high-speed channel modeling, estimation and equalization, anti-Doppler spreading tech- niques, fast power control, and dedicated network architec- ture. Because signal transmission in very high-speed scenarios will inevitably experience serious deterioration, it is imperative to develop key broadband mobile communi- cation techniques for such high-speed vehicles.     

Wuhan University Journal of Natural Sciences TOTAL CONTENTS

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Scale-based spatial data model for GIS

Being the primary media of geographical information and the elementary objects manipulated, almost all of maps adopt the layer-based model to represent geographic information in the existent GIS. However, it is difficult to extend the map represented in layer-based model. Furthermore, in Web-Based GIS, It is slow to transmit the spatial data for map viewing. In this paper, for solving the questions above, we have proposed a new method for representing the spatial data. That is scale-based model. In this model we represent maps in three levels: scale-view, block, and spatial object, and organize the maps in a set of map layers, named Scale-View, which associates some given scales.Lastly, a prototype Web-Based GIS using the proposed spatial data representation is described briefly.     

海南岛地体及其毗邻陆缘晚中生代—新生代古地磁研究和构造演化

本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。     

Exciton Seebeck in Molecular Systems

Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with     

Achieving Unusual States of Matter Under High Pressure

The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to