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1.
以模拟废水为对象,在传统的流化床反应器内,将活性污泥和经驯化的反硝化污泥按适当比例混合后,用聚乙烯醇(PVA)加适当添加剂将其包埋,并对短程硝化反硝化脱氮进行了研究.结果表明,在进水NH4+-N平均为53.60mg/L,COD为281.19mg/L,HRT12h,调控温度、溶解氧、pH等,出水亚硝化率和TN去除率分别可达95%和85%以上,短程硝化反硝化脱氮较理想.当进水COD含量从150mg/L增加到750mg/L,TN去除率从73.66%提高到96.79%.适合包埋颗粒短程硝化反硝化脱氮的最佳溶解氧浓度约为4.0mg/L.当pH一直维持在8.0左右,温度从30℃降到25℃过程中,短程硝化反硝化并未遭破坏.当温度维持在25℃,pH从8.0降到7.5,连续运行约5个周期后,短程硝化反硝转变为全程的硝化反硝化.  相似文献   

2.
CAST分段进水深度脱氮性能及在线控制   总被引:5,自引:0,他引:5  
以生活污水为处理对象,考察循环式活性污泥法(CAST)分段进水深度脱氮在线控制工艺中有机物降解、硝化和反硝化反应过程中氧化还原电位(ORP)及pH值的变化规律,建立这些控制参数与有机物去除、硝化和反硝化反应过程中主要污染物指标间的相关关系。研究结果表明:根据ORP及pH曲线上的特征点适时地停止曝气与进水缺氧搅拌,能更加有效地控制CAST多段进水工艺,达到深度脱氮的目的,并尽可能降低运行成本;当进水COD为155.0~443.6mg/L和NH4+-N质量浓度为57.98~82.40mg/L时,系统最终出水COD(化学需氧量)低于40mg/L,NH+4-N质量浓度低于0.5mg/L,TN(总氮)质量浓度低于2.0mg/L;在17,23和30℃时,升高温度能显著提高系统反硝化效果,反硝化速率随温度上升而递增;当原水有机碳源充足时,分段进水次数增多,由于反硝化速率加快,反应时间缩短,且反应末端外碳源投加量减少;采用CAST分段进水深度脱氮工艺系统除磷性能稳定,且去除率可达90%以上。  相似文献   

3.
目的研究溶解氧(DO)、温度、pH值和水力停留时间(HRT)对UASB厌氧氨氧化反应器脱氮性能的影响,寻找快速有效的脱氮处理途径.方法试验进水以人工配水的方式模拟城市生活污水,分别考察UASB反应器在不同的DO、温度、pH值和HRT反应条件下,通过检测进、出水中NH_4~+-N、NO_2~--N与NO_3~--N的质量浓度,分析UASB厌氧氨氧化反应器的脱氮性能,并确定最优环境因素.结果在进水中NH_4~+-N和NO_2~--N质量浓度分别为50 mg/L和66 mg/L、ρ(DO)1 mg/L、温度为30~35℃、pH=7~8、HRT=12 h的反应条件下,该反应器中的菌种具有最大的生物活性,污水的脱氮效果最优,总氮(TN)去除率维持在80%以上.结论厌氧氨氧化反应最佳条件的确定,为厌氧氨氧化工艺脱氮性能稳定性的控制起到关键作用.  相似文献   

4.
从螺旋升流式SUFR-UCT系统好氧反应器的活性污泥中分离得到一株好氧反硝化菌Y4,经16S rDNA系列相似性比较和系统发育分析初步鉴定属于Gordonia.sp(戈登氏菌属)。对菌株Y4反硝化能力进行试验研究,结果表明菌株Y4可以在好氧条件下有效去除培养液中的硝酸盐氮,在初始硝酸盐氮质量浓度为286 mg/L时,48 h脱氮效率可达61.2%。另外试验考察了溶解氧和温度对菌株Y4反硝化效果的影响,结果显示Y4有较高的氧耐受力,在DO为2~11.8 mg/L时都可保持较高的脱氮率;菌株Y4对温度适应性强,在30 ℃时脱氮效率高达90%。试验证明在螺旋升流式SUFR-UCT系统中存在有较好反硝化性能的好氧反硝化菌。  相似文献   

5.
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   

6.
本文采用SBBR反应器处理人工模拟废水,考察在不同C/N值条件下反应器的处理效果及氮的转化情况。试验结果表明,在室温条件下,进水氨氮浓度为120mg/L左右,保持溶解氧在2.0-2.5mg/L,运行方式为2.5(曝气)-1.5(停曝)-2.5(曝气)-1.5(停曝),当C/N值为5、6时系统脱氮效果最好,且系统主要脱氮方式为同步硝化反硝化和短程硝化反硝化。  相似文献   

7.
为进一步降低猪场示范工程排放废水中COD和氨氮的浓度,本试验尝试以葡萄糖配水模拟猪场废水,在同一个UASB反应器内实现同步的厌氧氨氧化、甲烷化和反硝化反应,以达到同时除碳脱氮的目的。结果表明,接种不同活性污泥于同一个UASB反应器内,经过约48 d反应器启动成功。在完成启动的反应器中添加亚硝酸盐氮和氨氮,使pH维持在7.3~8.3,温度、进水流量、回流量和水力停留时间等均与启动阶段保持一致,可逐步实现同步厌氧氨氧化和甲烷化反硝化。此阶段进水CODCr为500 mg/L,CODCr去除率在80%~90%之间,NO2-N去除率接近100%,氨氮去除率较低且处在波动状态。但是适当降低进水中有机物浓度,可在同时存在亚硝酸盐氮和氨氮的情况下提高厌氧氨氧化菌的竞争能力。当仅降低进水CODCr浓度(由500mg/L降至100 mg/L)时,氨氮去除率能缓慢升至30%以上。  相似文献   

8.
采用UASB反应器研究当NaCl质量浓度为2~35 g/L时对反硝化脱硫工艺以及微生物群落结构的影响。结果表明:NaCl从2 g/L增加至35 g/L的过程中,提高S∶C∶N至1∶3∶1可以保持高的单质硫产率;反应器内异养反硝化菌属所占比例随NaCl质量浓度的增加而减小,而自养反硝化菌属所占比例却随之增加;NaCl存在时,有机物的增加能够影响亚硝酸盐还原速率,从而使硫化物氧化停留在单质硫阶段,且高质量浓度NaCl条件下兼性自养反硝化微生物能同时参与硫化物的氧化、硝酸盐的反硝化和有机物的降解,使反硝化脱硫工艺维持较好的处理效果。  相似文献   

9.
文章研究了以甘油为碳源的生物反应器,在相同的硝酸盐氮浓度和甘油浓度梯度下,分别投加纯反硝化菌种和土著反硝化菌种时,去除地下水中硝酸盐的情况。结果表明,投加反硝化菌的反应器启动较快,去除效果较好,硝酸盐氮去除率可达到97.7%以上。在碳源充足的情况下,脱氮时效性差异不明显,反应器pH在7.0±0.2范围内波动。该研究旨在...  相似文献   

10.
在传统SBR工艺中,应用一种新型的纳米活性碳纤维悬浮填料,考察其对污水的脱氮除磷效果,并确定其最佳运行条件.结果表明:以进水30min—曝气4h—搅拌2h—沉淀1h—出水30min—闲置30min为最佳运行工况,在此工况运行时,进水NH3—N(氨氮)浓度为16.2~31.8 mg/L,出水NH3—N浓度为0.22~1.55 mg/L,NH3—N(氨氮)去除率为98.6%~95.1%;进水TN(总氮)为19.8~39.1mg/L,出水TN为5.94~13.68mg/L,TN去除率为70%~65%;进水TP(总磷)为3.2~4.5 mg/L,出水TP为0.46~1.13 mg/L,TP去除率为85.6%~75%,系统有较好的脱氮除磷效果,同时还存在同步硝化反硝化过程,以及较好的反硝化除磷功能.  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.
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   

15.
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   

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

18.
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   

19.
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   

20.
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   

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