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1.
A/O-MBBR工艺处理制革废水的研究   总被引:2,自引:1,他引:1       下载免费PDF全文
介绍了A/O-MBBR工艺对制革废水的进一步处理,考察了废水的有机物处理效果及氨氮(NH3-N)的处理效果。实验结果表明,当填料填充比例为60%时,有机物的处理效果:随着水力停留时间(HRT)的延长,COD去除率增加,当HRT达12 h时COD去除率达到92%;在HRT为12h时,随着进水COD质量浓度增加,COD去除率增加,在400 mg.L-1时达到95%,之后随COD质量浓度的继续增大其去除率有所下降。氨氮的处理效果:随着HRT的逐渐增大,氨氮质量浓度不断降低,在HRT为12 h时,出水氨氮质量浓度小于1.5 mg.L-1;氨氮去除率随进水COD质量浓度变大呈上升趋势,COD质量浓度在400 mg.L-1时氨氮去除率达到98%。  相似文献   

2.
人工湿地已成为广泛运用的污水处理方式,但仍存在效率较低等缺陷,而以人工湿地耦合多种强化工艺已成为近年来的研究热点。分别构建了磁场强化和光催化强化的人工湿地,针对不同进水浓度和水力停留时间(hydraulic retention time,HRT)(24、48、72 h),探究在磁场和光催化强化作用下的人工湿地对污水中TP、PO43--P、NH4+-N和CODCr的去除效果。研究结果表明,施加磁场后可促进人工湿地系统对NH4+-N和CODCr的去除,当HRT为24~72 h时,磁场强化的人工湿地对NH4+-N和CODCr的去除率分别能达到58.77%~96.91%、41.16%~85.42%。光催化作用由于大量自由基的生成,对污水中部分污染物降解效果明显,其对TP的去除率最大能达到59.85%,相比传统的人工湿地去除率提高了27.82%;去除NH  相似文献   

3.
本研究以竹炭和砾石为组合填料,开展了水平潜流人工湿地和垂直流人工湿地对生活污水净化效果的比较研究。结果表明,水平潜流人工湿地对生活污水中COD、总氮和总磷的平均去除率分别为72.2%、47.8%和59.8%,垂直流人工湿地分别为75.0%、48.1%和58.2%。两种人工湿地中COD去除率均随水力停留时间(HRT)的增加而提高,而总氮和总磷去除率分别在HRT=3.5d和HRT=2d最高。不同人工湿地中细菌数量为水平潜流湿地稍高于垂直流湿地,根区高于非根区,而真菌数量则相反,且细菌和真菌的数量均随着HRT的增加而增加。  相似文献   

4.
膨胀蛭石用于人工湿地去除氮磷的研究   总被引:1,自引:0,他引:1  
采用实验室模拟上向流人工湿地的方法研究了系统运行参数对膨胀蛭石去除氮、磷效果的影响.结果表明:膨胀蛭石的吸附作用在运行前期对氮、磷的去除起主要作用,在运行后期,氮、磷去除主要依靠微生物的作用;挂膜膨胀蛭石较未挂膜膨胀蛭石对氮、磷的去除率分别提高了9.8%,9.5%;膨胀蛭石人工湿地中TN,TP的进水质量浓度在0~100 mg/L,0~8 mg/L范围内时,其去除率随进水质量浓度的增大而增大,当进水质量浓度超过这个范围时,填料的吸附作用降低,生物膜的降解作用增强.膨胀蛭石是一种性能优异的人工湿地填料,对其进行人工挂膜可有效增强其去除氮、磷的能力.  相似文献   

5.
焦化废水经常规二级生物处理后仍残留大量难降解有机物,其排放会对环境构成危害。本研究采用铁炭法强化人工湿地来深度处理外排焦化废水,考察其有机物处理效果并与砾石湿地进行对比。研究结果表明:HRT为5d时,铁炭法强化人工湿地对COD的平均去除率分别为24.35%,高于砾石人工湿地的9.25%,并将BOD5/COD比值从0.1提高到0.35,提高了可生化性;铁炭法强化人工湿地对酚类、含氮类、苯系物、卤代烃(醇)等典型难降解有机物均有良好的降解效果,有机物种类从进水的41种减少到出水的17种,而且含量均有大幅削减。  相似文献   

6.
两种人工湿地不同填料层净化污水效果研究   总被引:1,自引:0,他引:1  
通过采集复合垂直流人工湿地(IVCW)和水平潜流人工湿地(HSCW)侧面不同高度的水样,初步研究了两种湿地填料的表层、中层、底层分别对污水中CODCr,TN,TP的净化效果.结果显示:①对CODCr的去除,两种人工湿地均未表现出显著差异.②两种湿地对TN的去除,主要取决于填料的中层和底层.③IVCW的填料表层除磷效果稳定,随环境因素变化,填料的中、底层TP去除率存在显著差异;HSCW中除磷主要在填料的底层,表层和中层填料容易出现明显的基质磷释放现象.  相似文献   

7.
采用粉末活性炭(PAC)-超滤(UF)一体化工艺处理微污染水,考察投炭量对浊度、UV254和CODMn去除效果和对膜污染的影响以及有机物去除效果随PAC停留时间的变化。研究结果表明:超滤膜出水浊度保持在0.100 NTU以下,且不受进水浊度以及PAC投加量的影响。在10,20和40 mg/L投加量下,随着PAC投加量增加,有机物去除率逐渐提高,但单位质量PAC有机物去除效果逐渐下降,10 mg/L PAC可以满足试验水质条件下经济性和出水水质的要求。PAC对有机物去除效果随停留时间增加而降低,较高PAC投加量下降幅度较小。PAC-UF工艺可以有效控制膜污染,次氯酸钠与酸、碱形成的复合药剂对跨膜压差恢复效果最佳。  相似文献   

8.
为了探讨水力停留时间及水力负荷对人工湿地处理效果的影响,构建6种不同类型的人工湿地进行中试研究,分析其在不同水力条件下对农村生活污水的净化效果。结果表明:在相同的水力条件下,垂直流人工湿地对污染物的去除率最高,表面流人工湿地的最低;湿地的最佳水力停留时间为48 h,总氮去除效果最好的是垂直上行人工湿地,去除率为93.02%,总磷、化学需氧量去除效果最好的是垂直下行人工湿地,去除率分别为91.71%、 81.67%,氨氮去除效果最好的是水平潜流人工湿地,去除率为72.73%;除化学需氧量外,各人工湿地处理效果都随水力负荷的增加而劣化;表面流人工湿地的最佳水力负荷为5 cm/d,垂直流与水平潜流人工湿地的最佳水力负荷为15 cm/d;挡板的增设可以延长湿地的水力停留时间,改善处理效果,增设挡板适合的水力负荷范围为15~25 cm/d。  相似文献   

9.
采用悬浮载体生物流化床工艺处理城市生活污水,考察了进水pH对其处理效果的影响.结果表明,进水pH变化不影响有机物去除效果;氨氮(NH3-N)去除率随pH上升而上升,最佳pH为7.5;当pH在6.5~8.0之间变化时,总氮(TN)去除率基本保持在50%以上,但当pH值>8.2和<6.1时,TN去除效率有着下降的趋势.因此在指定试验条件下,pH变化不影响有机物的去除;pH为中性或偏碱性的环境下,反应器对NH3-N及TN有很好的去除效果.  相似文献   

10.
采用填充聚氨酯(FPUFS)载体的上流式生物氧化反应器处理含烃废水中的硫化物,考察了曝气量、水力停留时间(HRT)、进水硫化物浓度、pH值和进水石油烃浓度对硫化物生物氧化的影响。结果表明,在曝气量为300mL/min,HRT为90min,进水硫化物浓度<300mg/L,pH值为6.1~7.8的条件下,硫化物去除率在80%以上。在试验考察的石油烃浓度范围内,反应器对总有机碳(TOC)没有明显的去除效果,石油烃对硫化物去除率的影响不超过5%,但硫酸根转化率随石油烃浓度的增加显著下降。  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.
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   

13.
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   

14.
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   

15.
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   

16.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

17.
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.  相似文献   

18.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

19.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

20.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

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