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1.
斜发沸石对氨氮吸附性能的试验分析   总被引:24,自引:0,他引:24  
通过静态试验、动态试验和再生试验研究了天然斜发沸石吸附氨氮的热力学性质、再生性能和影响因素.试验结果表明:斜发沸石对氨氮的静态饱和吸附量为3 100 mg/100 g,当氨氮浓度为35 mg/L时,动态饱和吸附量为2 200 mg/100 g,分别是粉末活性炭、颗粒活性炭、硅藻土的20倍、23倍、27.5倍,选择重量比为3:7的NaCl NaOH混合液作为斜发沸石的再生剂可进行3次重复再生使用,有效寿命可达140 h以上.斜发沸石处理含氨废水具有重要实用前景.  相似文献   

2.
研究以开发经济型处理低浓度含氨海水的工艺为目标,选用对氨氮有较强选择性和吸附性的天然斜发沸石作为吸附材料,将含氨氮海水通过烧杯实验和连续通水实验,系统地考察进水氨氮的浓度、pH值、沸石用量,以及洗脱条件对氨氮吸附特性的影响.结果表明,新鲜沸石处理低浓度含氨氮海水效果较好,去除效率可以达到75%左右;新鲜沸石穿透后,用海水 HCl的洗脱效果最佳,洗脱率可以达到98.2%.  相似文献   

3.
沸石分子筛因其特殊的结构特性对氨氮具有较高的吸附性能.将天然斜发沸石在250℃下高温改性,并用于含氨氮溶液的等温吸附处理,获得了在不同氨氮初始质量浓度下的改性沸石等温吸附曲线.根据朗格缪尔吸附理论拟合得到改性沸石的等温吸附方程1/qe=7.589 86/Ce+0.137 39,并求得其对氨氮的理论最大吸附量qm为7.278 6 mg/g.通过对沸石曝气生物滤池系统在不同水力负荷和气水比条件下的运行研究,总结出改性斜发沸石作为曝气生物滤池工艺的最佳水力负荷为0.15~0.25m3/(m2.h),气水比为20∶1.  相似文献   

4.
斜发沸石去除氨氮及其再生的研究   总被引:1,自引:0,他引:1  
为了有效去除污水中的氨氮,采用斜发沸石进行污水中氨氮的吸附去除研究,同时探讨了化学再生和生物再生的效果.结果表明,氨氮在沸石上吸附符合Langmuir吸附等温式;生物化学再生后沸石,经过2个月稳定运行,采用Na^+质量浓度2 000 mg/L,气水比为5∶1,温度为15-26.5℃时,氨氮的去除效率可超过80%.沸石可以作为一种有效的氨氮吸附材料并且可有效再生.  相似文献   

5.
以天然斜发沸石为原料,研制硅基沸石滤料,并以硅基沸石滤料作为填料,研究探讨硅基沸石滤料对废水中氨氮的静态吸附作用.对比天然斜发沸石,通过质量浓度与吸附量的Langmuir曲线和Freundlich曲线,对硅基沸石滤料的吸附机理和离子交换性能进行分析.实验表明,自行研制的硅基沸石滤料符合国家标准,对氨氮的静态吸附容量可高...  相似文献   

6.
:以粒径为 1 ~1. 5 mm 和 2 ~4 mm 的细、粗两种天然斜发沸石为实验材料,进行氨氮吸附等温线实验和吸附动力学实验,探讨沸石对雨水中氨氮的吸附规律。结果表明,实验沸石对 NH+4的吸附等温线符合 Frundlich 公式,且细沸石和粗沸石对氨氮吸附量的极限值分别为 5. 83 mg/g 和 18. 375 mg/g;细沸石比粗沸石有更好的吸附效果;粗沸石对氨氮的吸附反应为一级反应,吸附速率常数为 0. 022 212 g. m 2. h 1。  相似文献   

7.
为了探索天然片沸石对高氨氮废水的吸附机理及最佳再生方法,选取河北省天然片沸石为研究对象,采用单因素试验法,通过吸附动力学、吸附等温线、吸附热力学进行研究。结果表明,在温度25℃下,粒径为50~600μm,氨氮质量浓度为500 mg/L时,准二级动力学方程更能准确地描述片沸石对氨氮的吸附过程,颗粒内扩散和液膜扩散在吸附过程中占主导地位;当温度为45℃,片沸石的饱和吸附量为7.81mg/g,吸附等温试验较符合Freundlich模型。吉布斯自由能ΔG<0,吸附是自发的吸热反应,适当升高温度可提高片沸石的吸附量。对饱和片沸石的最佳再生溶剂为0.1mol/L的NaCl溶液,解吸率为79%,且可多次洗脱再生。研究结果有助于进一步提高片沸石在氨氮废水处理中的经济效益和环境价值,使得沸石在工业废水处理中的应用前景更加广阔。  相似文献   

8.
对沸石分子筛、天然沸石、造纸厂废渣(木屑和蔗髓)吸附制浆废气中的甲醇进行初步研究,探讨吸附法处理制浆厂废气的可行性.研究吸附温度、吸附时间、甲醇浓度对ZSM-5疏水分子筛、5A分子筛和天然斜发沸石吸附甲醇的影响,探讨不同水分含量的木屑和蔗髓吸附废气中甲醇的效果.研究结果表明:ZSM-5分子筛对甲醇的吸附量最大,5A分子筛次之,天然斜发沸石最小;该3种无机吸附材料对甲醇的饱和吸附量均随吸附温度的降低而增大,随气相甲醇浓度升高而增大,但温度越高达到饱和吸附所用时间越短,40℃时ZSM-5分子筛、5A分子筛和斜发沸石的饱和吸附量分别为15.00mg/g、4.90,mg/g和2.68,mg/g.水分含量影响木屑和蔗髓吸附甲醇的性能,水分含量越高,达到吸附饱和用时越长,饱和吸附量越大;实验条件下,水分含量为59.89%,的松木木屑、55.29%,的桉木木屑和54.82%,的蔗髓分别在吸附12h、10h和5h左右达到饱和,饱和吸附量分别为16.30mg/g、12.84mg/g和13.56mg/g.造纸厂的木屑和蔗髓等废渣可先用来吸附制浆废气,然后再送废渣炉进行燃烧处理.  相似文献   

9.
分别用粉末状沸石和颗粒状沸石在静态和动态条件下吸附处理废水中的氨氮,进行沸石吸附氨氮的吸附等温线、吸附动力学、动态吸附及再生实验。结果表明:Freundlich方程和Langmuir方程均能描述沸石对氨氮的吸附行为,但Langmuir方程的拟合相关性优于Freundlich方程;用假二级方程能很好地拟合沸石吸附氨氮的吸附动力学实验数据;在其他实验条件相同的条件下,粒径为0.8~1 mm的沸石去除氨氮效果明显优于粒径为3~5 mm和1~2 mm的沸石,同一粒径的沸石在废水流速为4 m/h时吸附效果最好;当沸石质量为35 g时,以0.9 mol/L NaCl做再生液,再生时间5 h,再生液用量为0.7 L的条件下,沸石经5次再生后仍具有较好的吸附效果。  相似文献   

10.
斜发沸石去除废水中氨氮及其再生研究   总被引:1,自引:0,他引:1  
利用天然斜发沸石离子交换脱除氨氮机理处理污水厂二级出水,通过对沸石离子交换柱的NH4+交换量、沸石柱离子交换柱的再生和再生盐水的脱氮进行分析,确定了去除污水厂二级出水中氨氮的工艺流程和适宜参数,经处理后氨氮含量低于5 mg/L,达到一级A的国家排放标准(GB198918-2002)。本研究可为污水厂二级出水中氨氮的处理提供一定的技术依据。  相似文献   

11.
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   

12.
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   

13.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

14.
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。  相似文献   

15.
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  相似文献   

16.
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  相似文献   

17.
18.
The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   

19.
R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).  相似文献   

20.
The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.  相似文献   

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