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1.
沸石的改性及除磷性能研究   总被引:4,自引:0,他引:4  
天然沸石经1 mol/L氢氧化钠浸泡1 h后又经20%氯化镁浸泡2d,然后在500℃下焙烧,改性后沸石除磷能力有较大提高.在此基础上研究了时间、投加量以及不同质量浓度磷水样条件下改性沸石的除磷效果.随着接触时间的延长,沸石的除磷效果增强,但在180 min以后增加缓慢,其吸附速度符合斑厄姆公式;随着原水质量浓度的增大,吸附容量也逐渐增大.吸附等温线可用Freund lich等温式描述,并通过电镜扫描从微观上进一步探讨了改性前后沸石的表面结构变化.  相似文献   

2.
市政污水厂二级出水深度脱氮除磷吸附材料   总被引:4,自引:1,他引:4  
针对二级出水中氮、磷含量较高问题,对采用吸附法去除水中的氮、磷的天然吸附剂进行了改性和复合处理实验.结果表明,对天然沸石进行的四种改性方法中,改性效果排序为:盐热改性>盐改性>热改性>酸改性.经过盐热改性后的沸石脱氮能力提高了31.58%,最佳改性条件为:质量分数5.7%的NaCl改性2 h,500℃煅烧0.5 h.经复合后,改性沸石的除磷能力提高了68.35%,复合最佳条件为:LaCl3质量分数0.4%,复合时间1 h,200℃复焙烧失1 h.应用改性和复合后的吸附剂处理二级出水,可以有效地解决出水中氮、磷含量超标的问题.  相似文献   

3.
为了解决污水处理厂后续脱氮除磷处理工艺的占地及成本问题,以廉价天然沸石为原料,制备了能够同步脱氮除磷的复合改性沸石,研究了不同制备条件对吸附效果的影响.研究结果表明,季铵盐-氯化钠复合改性沸石不仅去除氨氮,而且实现了同步去除磷和硝氮,脱氮除磷速度快,效率高,且去除互不影响;对氨氮、磷和硝氮的吸附数据均符合伪二级动力学方程.当该沸石在生活污水中的投加量为50 g/L时,实际出水水质可由一级B一步提高到一级A,对氨氮、硝氮和磷的去除率分别高达71.09%,91.18%,93.11%.吸附饱和后的沸石经单一的NaCl溶液再生后可循环使用,且再生时间短,操作简单.该复合改性沸石在实际生活污水的处理中具有良好的应用前景.  相似文献   

4.
对沸石、膨胀蛭石、瓷砂陶粒、页岩陶粒和黏土陶粒5种硅酸盐填料改性前后对水中磷的吸附性进行了研究,并分析了硅酸盐填料投加量、吸附时间和pH等因素对磷去除率的影响.结果表明:改性前,膨胀蛭石对磷的吸附性最好,瓷砂陶粒次之,黏土陶粒、页岩陶粒和沸石较差.经过镁盐和铝盐改性后,改性膨胀蛭石除磷效果最好,其最佳使用条件为:填料用量10 g/L,pH 5~9,吸附时间60 min,此时磷去除率可达97%以上.  相似文献   

5.
介绍了处理含磷废水的生物法和改性沸石处理法,阐述了污水除磷技术的新进展,探讨了生物法与化学法有机结合除磷的可能性,指出了沸石强化A2/O工艺除磷的可行性。  相似文献   

6.
沸石作为一种廉价的无机非金属的矿物,对生活污水中的氮磷具有一定的吸附能力,由于天然沸石对氮磷的吸附效果有限,所以需经过物理化学的方法通过提高沸石的空隙率和阳离子交换容量,来达到有效去除污水中氮磷的目的,故本文采取复合改性沸石对含氮磷废水进行研究,试验结果表明:氯化钠质量分数为5%、煅烧温度为400℃制得的复合改性沸石,对氨氮去除率可达到74.2%;镧改性沸石再进行高温处理,对磷去除率为86%。天然沸石经复合改性后对于氮磷的去除率大大提高。  相似文献   

7.
针对污水处理后的排放未达标水体,利用沸石这种天然价廉的多孔材料,经过一系列改性,引入活性功能基团,得到高效稳定的除磷吸附剂.以天然沸石为原材料,研究发现原始沸石的吸附效果不佳只能达到10%~20%,对其进行时间、温度单因素实验,进行比对.由于去除效果不佳选择对其进行改性,通过对酸碱盐分别浸泡,最后得出用20%Mg Cl2最佳,利用静态试验考察了p H值、温度、吸附剂投加量、吸附时间等方面对吸附剂吸附容量的影响;去除率在条件适宜时能达到70%~80%.最后对时间、温度、投加量进值行正交试验研究,确定了吸附的最佳条件为25℃,160 min,5 g,此时去除效果可达78%.  相似文献   

8.
以浙江缙云天然斜发沸石为原料,研究通过焙烧后超声碱洗除硅,再经超声补铝后用钠盐复合改性对沸石吸附K~+性能的影响,提高对海水中K~+的吸附量.结果表明:采用0.18~0.38 mm的天然沸石,200℃下焙烧1.5 h,0.2 mol·L~(-1)的NaOH溶液超声处理2.0 h,0.5 mol·L~(-1)的AlCl_3溶液超声处理2.0 h,20%(质量分数)NaCl溶液煮沸30 min的方法复合改性得到的沸石对K~+吸附性能最佳,吸附量可达到25.64 mg·g~(-1),为天然斜发沸石吸附量的4.2倍.对最适宜条件改性后的沸石进行吸附K~+的动力学研究,其吸附过程符合准二级动力学模型.  相似文献   

9.
天然沸石在我国储量丰富,但其本身亲水性性质和结构特点使其对有机废水的处理效果并不太显著,可以通过改性提高天然沸石对有机废水的处理效果.针对天然沸石除酚性能较差,通过实验研究了天然沸石的改性方法,以提高其对有机废水中酚类的吸附能力,为沸石经改性后处理废水的效果提供了科学依据.结果表明,活化改性后的沸石对酚类有机废水有一定的处理效果,去除率在10%~50%之间,废水质量浓度相同的不同改性条件下,NaCl活化效果最好,且NaCl的改性浓度为0.3 mol/L时达到最佳处理效果.去除率:NaClNaOHH_2SO_4加热,去除率随废水质量浓度上升而逐渐下降,在中性条件下处理效果最佳.  相似文献   

10.
目的 研究石灰石不同改性方法对生活污水的除磷性能影响,提高传统湿地填料对农村分散性生活污水中磷的吸附容量与稳定性,获得更高效、更快速、更持久的除磷效果.方法 对石灰石填料进行不同浓度的酸、碱、盐单一改性以及组合改性,通过吸附量和除磷率的比较确定除磷性能最好的改性方法.结果 石灰石经NaOH溶液改性后的除磷率反而下降,经...  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.
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 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   

15.
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   

16.
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   

17.
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   

18.
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   

19.
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   

20.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

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