水力空化在废水处理的应用中英文Word文档格式.docx

1、Received in revised form 8 October 2015 修改接收日期 2015.10.08Accepted 15 October 2015 接受日期 2015.10.15Available online XXXXKeywords：关键词Wastewater 废水Cleaning 净化Hydrodynamic cavitation 水力空化Pharmaceuticals 药物Cyanobacteria 蓝藻Microalgae 微藻Viruses 病毒Legionella bacteria 军团菌ABSTRACT摘要The use of acoustic cavitati

2、on for water and wastewater treatment（cleaning） is a well known procedure. Yet, the use of hydrodynamic cavitation as a sole technique or in combination with other techniques such as ultrasound has only recently been suggested and employed声空化用于水和废水处理（净化）是一个众所周知的过程。然而，水力空化作为一种单独的技术或与其他技术（如超声波）结合使用直到最

3、近才被建议和使用。In the first part of this paper general overview of techniques that employ hydrodynamic cavitation for cleaning of water and wastewater is presented本文第一部分介绍了应用水力空化作为水、废水净化技术的发展概况。In the second part of the paper the focus is on our own most recent work using hydrodynamic cavitation for remov

4、al of pharmaceuticals （clofibric acid, ibuprofen, ketoprofen, naproxen, diclofenac, carba- mazepine）, toxic cyanobacteria （Microcystis aeruginosa）, green microalgae （Chlorella vulgaris）, bacteria （Legionella pneumophila） and viruses （Rotavirus）from water and wastewater.在本文的第二部分中，重点介绍了我们用流体力学空化技术去除水和

5、废水中药物（环丙酸、布洛芬、酮洛芬、萘普生、双氯芬酸、卡巴-马西平）、有毒蓝藻（铜绿微囊藻）、绿藻（小球藻）、细菌（嗜肺军团菌）和病毒（轮状病毒）的最新工作。As will be shown, hydrodynamic cavitation, like acoustic, can manifest itself in many different forms each having its own distinctive properties and mechanisms. This was until now neglected, which eventually led to poor p

6、erformance of the technique. We will show that a different type of hydrodynamic cavitation （different removal mechanism） is required for successful removal of different pollutants.正如将显示的那样，流体动力空化和超声空化一样，可以以许多不同的形式表现出来，每种形式都有其独特的特性和机制。到目前为止，这一点一直被忽视，最终导致了这项技术的糟糕表现。我们将证明，成功去除不同的污染物需要不同类型的水力空化（不同的去除机制）

7、。The path to use hydrodynamic cavitation as a routine water cleaning method is still long. but recent results have already shown great potential for optimisation,which could lead to a low energy tool for water and wastewater cleaning.将水力空化作为常规的水净化方法还有很长的路要走。但最近的结果已经显示出巨大的优化潜力。这可能会导致一种用于水和废水净化的低能耗工具。

8、1. Introduction1.引言Availability of water is becoming an increasing concern in the globalised world, both in developed and in developing countries.在全球化的世界里，无论是发达国家还是发展中国家，水的可获得性正成为一个日益令人担忧的问题。A sustainable use of water sources could result in the search of additional water sources or even in recyclin

9、g wastewater treatment plant effluents 1. The goal of biological wastewater treatment is a stepwise oxidation of organic pollutants aiming to achieve complete mineralisation. Yet, numerous wastewater constituents are persistent to biodegradation or they are only subjected to minor structural changes

10、 instead of complete transformation into carbon dioxide and water. Alternatively, they may be eliminated by applying advanced abiotic treatment processes such as membrane filtration, UV degradation, ozonation, advanced oxidation processes, one of them being cavitation.水资源的可持续利用可以导致寻找更多的水源，甚至可以回收废水处理

11、厂的污水1。生物废水处理的目标是逐步氧化有机污染物，以达到完全矿化。然而，许多废水成分都是顽固而难以生物降解的，或者它们只受到微小的结构变化的影响，而不是完全转化为二氧化碳和水。或者，可以通过应用先进的非生物处理工艺如膜过滤、UV降解、臭氧氧化、高级氧化工艺来消除它们，其中之一是空化。Cavitation, ie. the appearance of vapour cavities inside an initially homogeneous liquid medium, occurs in very different situations. It can be defined as th

12、e breakdown of a liquid medium under very low pressures. This makes cavitation relevant to the field of continuum mechanics and it applies to cases in which the liquid is either static or in motion. When an oscillating pressure field is applied over the free surface of a static or nearly static liqu

13、id contained in a reservoir, cavitation bubbles may appear within the liquid bulk if the oscillation amplitude is large enough. This type of cavitation is known as acoustic cavitation. However, cavitation can also occur in a liquid, which is in motion. In liquid flows, this phase change is generally

14、 due to local high velocities, which induce low pressures. The liquid medium is then broken at one or several points of weakness （gas bubbles, impurities） and larger voids （bubble clouds） appear whose shape depends strongly on the structure of the flow. In the developed cavitation, which is the focu

15、s of the present study, the flow follows a distinctive pattern where cavitation structures of different shapes and sizes are shed from the attached cavity （Fig. 1a） - the flow is from the right to the left.空化，即。在完全均匀的液体介质中，蒸汽腔的出现是在非常不同的情况下发生的。它可以定义为液体介质在极低压力下的击穿。这使得空化与连续介质力学领域相关，它适用于液体是静止或在运动的情况。当振荡

16、压力场作用于水池中含有的静止或接近静止液体的自由面上时，如果振荡幅度足够大，液体内部可能会出现空化气泡。这种类型的空化称为声空化。然而，空化也可能发生在运动中的液体中。在液体流动中，这种相变通常是由于局部高速度引起的低压力。然后，液体介质在一个或几个弱点（气泡、杂质）处“破裂”，出现较大的“空洞”（泡沫云），其形状强烈地取决于流动的结构。在本研究的重点-空化的发展过程中，水流遵循不同形状和大小的空化结构从附着的空穴中脱落的独特模式（Fig. 1a） - 水流是从右到左的。Developed cavitation occurs when the pressure difference betwe

17、en the outer flow and the inside of the attached cavity, forces the streamlines to curve towards the cavity and the surface beneath it. This causes the attached cavity to close and the formation of a stagnation point at which the flow is split into outer flow which reattaches to the wall and the re-

18、entrant jet which travels upstream, carrying a small quantity of the liquid to the inside the cavity. As the re-entrant jet travels upstream it looses momentum, turns upwards and cuts the attached cavity, causing cavitation cloud separation （shedding） . The cloud is then entrained downstream by the

19、main flow and can violently collapse in a region of pressure recovery. During the separation, circulation around the structure can appear, causing it to reshape, break up etc. Meanwhile the attached cavity begins to grow and the process is periodically repeated.当外部气流和附着的空腔内部之间的压差迫使流线向空腔及其下面的表面弯曲时，就会

20、产生空化。这导致附着腔关闭，并形成停滞点，在该停滞点处，流被分成重新附着到壁上的外部流和携带少量液体到腔内的上游流动的可再入的射流。在该停滞点处，流体被分割成重新附着到壁上的外部流和携带少量液体到腔内的可再入的射流。当再入射流逆流而上时，它会失去动量，向上翻转，“切割”附着的空腔，导致空泡云分离（脱落）。然后，云被主流卷到下游，在压力恢复的区域可能会猛烈坍塌。在分离过程中，可能会出现结构周围的循环，导致结构重塑、破裂等。与此同时，附着的空腔开始增长，并周期性地重复这一过程As the system pressure is decreased or the flow velocity is in

21、creased a small cavity will extend and grow longer and longer. It becomes a supercavity as soon as it ceases to close on the cavitator wall but inside the liquid, downstream of the cavitator （Fig. 1b）-the flow is from the right to the left. Supercavitating flow shows only one quasi steady vapour fil

22、led large scale cavity where larger disturbances in pressure and temperature are uncommon-it is not accompanied by noise, vibration and erosion, which would make the operation of a real facility somewhat easier.随着系统压力的降低或流速的增加，一个小空腔将会扩大并变得越来越长。一旦它停止关闭在空化器壁上，而是关闭在空化器下游的液体内部时，它就变成了超空化穴 （图1B）-水流从右到左，超空

23、化流显示只有一个准稳定的蒸汽填充的大型空腔，其中较大的压力和温度扰动是不常见的-它不伴随噪音、振动和侵蚀，这将使实际设施的操作变得更容易。Despite many obvious differences in appearance, on a small scale the principles which govern the hydrodynamic bubble and the acoustic bubble are basically the same. Once the cavitation bubble is generated, it may undergo a violent

24、collapse during which an intense shock wave is emitted.尽管在外观上有许多明显的不同，但在小范围内，支配水力空化泡沫和超声空化泡沫的原理基本上是相同的。一旦产生空化泡沫，它可能会经历猛烈的坍塌，在此期间会发出强烈的冲击波。Pressures up to a Gpa range and high local temperatures, in the order of 10000 K can be expected 2. These conditions are uniquely suited for mechanical substrate

25、surface or membrane cleaning, cell disruption or enhanced oxidation of chemical compounds最高可达GPa范围的压力和大约10000 K数量级的局部高温是可以预期的2。这些条件特别适合于衬底表面或膜的机械清洗、细胞破坏或增强化合物的氧化With cavitation one utilises i） extreme pressures and temperatures from cavitation collapses to disintegrate smaller organic molecules, whi

26、ch are otherwise harder to disintegrate using conventional biological methods and ii） disintegration of larger particles to enlarge the specific surface and thus increase the rate of hydrolysis and biodegradation of organic pollutants空化利用i）空化塌陷产生的极端压力和温度来分解较小的有机分子，否则用传统的生物方法很难分解；ii）大颗粒的分解扩大比表面积，从而增加

27、有机污染物的水解和生物降解的速度。Cavitation can be combined with conventional biological treatment using activated sludge. By decreasing the amount of persistent organic pollutants in wastewater treatment plant effluent, we will demonstrate the improved efficiency of treatment空化可以与使用活性污泥的常规生物处理相结合。通过减少污水处理厂出水中的顽固性有

28、机污染物的数量，我们将证明处理效率的提高。In the current industrial practice of wastewater treatment hydrodynamic cavitation is not used. Although laboratory experiments exist, the methods have not been routinely applied for practical use -some attempts include 3-6. This is, in our opinion, mainly due to lack of communi

29、cation between researchers- the environmentalists concentrate their efforts on ultrasonic cavitation, while the engineers do not realise the usefulness of cavitation and still treat it as a harmful phenomenon.在目前的污水处理工业实践中，并没有采用水力空化技术。虽然有实验室实验，但这些方法还没有被常规地应用于实际应用-一些尝试包括3-6。在我们看来，这主要是因为研究人员之间缺乏沟通-环保人

30、士将精力集中在超声波空化上，而工程师们没有意识到水力空化的有用性，仍然将其视为有害现象。Hydrodynamic cavitation has the potential to become energy efficient technique that can reduce currently necessary use of expensive chemical reagents for enhanced treatment process, which on the other hand also pose additional concerns when deposited into

31、environment. Cavitation as physical phenomena does not introduce any new chemicals to water and thus does not affect the environment after water is released into environment.水力空化有可能成为一种节能的技术，一方面可以减少目前强化处理过程中所需的昂贵化学试剂的使用，另一方面也会在沉积到环境中时带来额外的担忧。空化作为一种物理现象，不会向水中引入任何新的化学物质，因此水释放到环境中后不会对环境造成影响。Finally, as nowadays a lot of attention is put upon micropollutants such as endocrine disrupting compounds, it is expected that developed process of wastewater treatment with aid