物理化学水处理英文讲义
水处理专业英语翻译理论
专业英语翻译理论
POPs persistent organic pollutants 持久性有机污染物 TSP total suspended particle 总悬浮颗粒 TKN total Kjeldahl nitrogen 总凯氏氮 UASB up flow anaerobic sludge blanket 上流式厌氧污泥床 MBR membrane bioreactor 膜生物反应器 SBR sequencing batch reactor 间歇式活性污泥法
科学家深信一切物质都是不灭的 b. They are quite content with the data obtained from the experiment. 他们满足于试验中所获得的数据 c. We are not sure about the effect of this parameter on the quality of the effluent. 我们不能确定这个参数对出水水质的影响
专业英语翻译理论
2.1.4 语言习惯的转换 E.g.: a. Magnetism is used to measure the coldest temperature. 磁性可用来测很低的温度 b. Light-colored things reflect more light than dark-colored things. 浅色物体反射的光比深色物体多
专业英语翻译理论
3.1.2. 形容词译为动词
1. 英语中表示感觉、知觉、信念的词，如familiar、 confident、sensible of等在句中作表语时，译成动词。
a. Scientists are confident that all matter is indestructible.
水处理英语演讲 ppt
RIGHT CHOICE
Biological contact oxidation tank
(生物接触氧化池)
microorganism
少量污泥
The advantage
• ①Can effectively remove organic contaminants , and maintain good treatment effect • ②Simple and convenient operation , easy to manage , needless sludge return , sludge bulking phenomenon does not produce . • ③Generate less sludge , sludge particles larger , easy to precipitate
The belt thickener-press filter can squeeze sludge into filter cake with two belts after flocculation.
Its operation is simple, general staff can handle the entire process after a short period of training.
Valveless gravity filter (重力式无阀滤池）
Pressure filter (压力滤池)
Ordinary rapid filter (普通快滤池)
Low cost simple and mature process easy maintenance Higher surface load stable operation
化学水处理专业英语词汇
化学水处理acid cleaning (pickling) 酸洗acid-proof lining material防酸内衬材料acidic water 酸性水regeneration waste water 再生废水agitator 搅拌器air agitation device, agitationblower 空气搅拌装置，搅拌鼓风机aluminum oxide 氧化铝ammonia (hydrazine, phosphate) injection pump 氨(联氨,磷酸盐)喷射泵amount of hydrogen leakage 漏氢量anion 阴离子anion-exchanger, anionite阴离子交换剂anion (cation) exchange resin阴(阳)离子交换树脂Abackwash for the screen 滤网反冲洗ball catcher 胶球捕集器biochemical oxygen demand for 5 days (BOD5) 五天生化需(耗)氧量boiler chemical cleaning waste water storage tank with batchwisechemicals dosage 锅炉化学清洗废水，具有分批(断续)加药的储水箱boiler chemical dosing equipment锅炉化学加药设备carbon dioxide bottle 二氧化碳瓶cathodic protection system阴极保护系统cation 阳离子cation-exchanger, cationite阳离子交换剂chemical equivalence 化学当量chlorination local control panel,totally enclosed back (rear) doortype floor mounting steel cubicle加滤就地控制盘,全封闭后开门式地面安装钢柜chlorination plant 加氯站(间) chlorination (strainer) room加氯(漉网)间chlorination unit for potable water 饮用水的加氯装置chlorine injection equipment注(加)氯设备chlorine water 氯水clarifier, sand (activated carbon)filter 净化器,砂(活性碳)过滤器cleaned by sand blast 用喷砂法清理CO2 breathing unit CO2通气装置Concentration of chemicals, chemicals Injection point 药品浓度,药品注入点Condensate polishing equipment凝结水箱处理设备condenser on load cleaning equipment凝汽器带负荷清洗设备deionized water cooling 去离子水冷却dissolved oxygen density in sampled water 取样水中的溶解氧密度domestic resin and chemical reagent国产树脂和化学试剂dry chemical system for boilerburner zone, turbine main oil tankand oil purifier 锅炉喷燃器(喷嘴)区，汽机主油箱和油净化器的干化学药剂系统duplicated countercurrent regeneration type demineralization system双套逆流再生式除盐系统equalize the characteristics of wastewater and prevent the suspended solids from sedimentating使废水的特性均匀并防止固体颗粒沉凝filling resin (pit), resin holding pit装填树脂(坑),树脂存储坑fixed bed, regenerant, countercurrent regeneration, mixed bed固定床,再生剂,逆电流再生,混(合)床flocculation and sedimentation basin, neutralization basin, PH adjusting basin絮凝沉凝池,中和池,PH调节池flocculator, flocculation絮凝器,絮凝作用gas volume and time for gas replacement气体溶积和气体置换时间hydrochloric acid 盐酸hydrogen cooling system 氢冷却系统hydrogen gas contained in the sealoil in the form of bubbles以气泡形式包含在密封油中的氢气hydrogen gas supply unit 氢气供应装置hydrogen generating station 氢气发生站hydrogen generating unit 氢发生装置hydrogen peroxide 过氧化氢in order to oxidize hydrazine, in proportion to the raw water flow为了氧化联氨,与生水流量成比例industrial (element) analysis工业(元素)分析ion exchange resin 离子交换树脂iron oxide 氧化铁kinematic viscosity, acidity (alkality, alkalinity) value, flash point, freezing (pour) point动粘度,酸(碱)废值,闪点,凝固(流动)点liquid chlorine, caustic soda, colloidal silica 液体氯,苛性钠,胶体硅low turbidity of raw water生水的低浊度lubricating oil treatment system润滑油处理系统mechanical particles, transparency (diaphaneity), demulsification time机械颗粒,透明度,反乳化时间mercury and other inorganic compounds 水银和其他无机化合物method of back washing 反洗方法methylene orange alkalinity甲基橙碱度mild steel 低碳钢tar epoxy 焦油环氧树脂nitrogen sealing equipment氮密封设备oil separator, gravity separation油分离器,重力分离oily waste water treatment unit foroil tank area 油罐区含油废水处理装置oxide 氧化物oxygen (acetylene) generating station氧(乙炔)发生站peroxide 过氧化物polisher, degasifier, filtered watertank 精处理装置,除气器,过滤水箱polypropylene, polyethylene聚丙烯,聚乙烯potassium hydroxide 氢氧化钾pretreatment unit and demineralization 予处理装置和除盐装置process parameter 过程参数regenerative agent 再生剂remove dissolved oxygen in feed-water 除去给水中的溶解氧resin catcher 树脂收集器sacrificed anode for buried pipe直埋管道用的牺牲阳性sacrificed anode of cathodic protection 阴极保护的牺牲阳极sampler 取样器scale formation 水垢的形成sewer manhole 下水道检查井(入孔) sludge recalculation clarifier污水(泥)再循环净化器sodium hydroxide 氢氧化钠sodium hypochlorite 次氯酸钠sodium phosphate dosing pump磷酸钠加药泵sponge rubber ball recirculation多孔胶球再循环steel pipe with inside tar epoxy coating 具有内部焦油环氧的钢管strainer 滤网strong acid cation (bass anion) exchange resin强酸阳离子(碱阴离子)交换树脂strong acidity (basicity) styrenecation (anion) resin强酸(碱)性苯乙烯阳(阴)离子树脂suffix 词尾-ide 化合物chloride, ammonium chloride氯化物,氯化铵hitride, aluminum nitride氨化物,氨化铝-ate 酸盐sulphate, lead sulphate硫酸盐,硫酸铅nitrate, ammonium nitrate硝酸盐,硝酸氨-ite 亚酸盐sulphite 亚硫酸盐Teflon hose 聚四氟乙烯软管transparent container of syntheticresin 合成树脂透明容器treated water quality, suspended solids, hexane (被)处理水质,悬浮固体颗粒,乙烷under reduced hydrogen gas pressure在氢压降低的情况下water quality at the outlet of themakeup (waste) water treatment plant补给(废)水处理站的出口水质water sampling and analysis equipment水样和分析设备water treatment system 水处理系统。
水处理专业英语
1、给水工程water supply engineering原水的取集和处理以及成品水输配的工程。
2、排水工程sewerage ,wastewater engineering收集、输送、处理和处置废水的工程。
3、给水系统water supply system给水的取水、输水、水质处理和配水等设施以一定方式组合成的总体。
4、排水系统sewerage system排水的收集、输送、水质处理和排放等设施以一定方式组合成的总体。
5、给水水源water source给水工程所取用的原水水体。
6、原水raw water由水源地取来的原料水。
7、地表水surface water存在于地壳表面，暴露于大气的水。
8、地下水ground water存在于地壳岩石裂缝或工壤空隙中的水。
9、苦咸水(碱性水) brackish water ,alkaline water碱度大于硬度的水，并含大量中性盐，PH值大于7。
10、淡水fresh water含盐量小于500mg/L的水。
11、冷却水cooling water用以降低被冷却对象温度的水。
12、废水wastewater居民活动过程中排出的水及径流雨水的总称。
它包括生活污水、工业废水和初雨径流以及流入排水管渠的其它水。
13、污水sewage ,wastewater受一定污染的来自生活和生产的排出水。
14、用水量water consumption用水对象实际使用的水量。
15、污水量wastewater flow ,sewage flow排水对象排入污水系统的水量。
16、用水定额water flow norm对不同的排水对象，在一定时期内制订相对合理的单位排水量的数值。
17、排水定额wastewater flow norm对不同的排水对象，在一定时期内制订相对合理的单位排水量的数值。
18、水质water quality在给水排水工程中，水的物理、化学、生物学等方面的性质。
19、渠道channel ,conduit天然、人工开凿、整治或砌筑的输水通道。
水处理专业英语资料
1、给水工程water supply engineering原水的取集和处理以及成品水输配的工程。
2、排水工程sewerage ,wastewater engineering收集、输送、处理和处置废水的工程。
3、给水系统water supply system给水的取水、输水、水质处理和配水等设施以一定方式组合成的总体。
4、排水系统sewerage system排水的收集、输送、水质处理和排放等设施以一定方式组合成的总体。
5、给水水源water source给水工程所取用的原水水体。
6、原水raw water由水源地取来的原料水。
7、地表水surface water存在于地壳表面，暴露于大气的水。
8、地下水ground water存在于地壳岩石裂缝或工壤空隙中的水。
9、苦咸水(碱性水) brackish water ,alkaline water碱度大于硬度的水，并含大量中性盐，PH值大于7。
10、淡水fresh water含盐量小于500mg/L的水。
11、冷却水cooling water用以降低被冷却对象温度的水。
12、废水wastewater居民活动过程中排出的水及径流雨水的总称。
它包括生活污水、工业废水和初雨径流以及流入排水管渠的其它水。
13、污水sewage ,wastewater受一定污染的来自生活和生产的排出水。
14、用水量water consumption用水对象实际使用的水量。
15、污水量wastewater flow ,sewage flow排水对象排入污水系统的水量。
16、用水定额water flow norm对不同的排水对象，在一定时期内制订相对合理的单位排水量的数值。
17、排水定额wastewater flow norm对不同的排水对象，在一定时期内制订相对合理的单位排水量的数值。
18、水质water quality在给水排水工程中，水的物理、化学、生物学等方面的性质。
19、渠道channel ,conduit天然、人工开凿、整治或砌筑的输水通道。
(全英文)水处理课件——过滤
.01 .1 1 5 10 50 90 95 99 99.9 99.990.1 110Percent of Media with Smaller DiameterNaturally Occurring Sand Processed Filter Sand20 30 70 80 P a r t i c l e D i a m e t e r , m m Size Distribution of Typical Naturally Occurring and Processed Filter SandFigure by MIT OCW.Adapted from: MWH, J. C. Crittenden, R. R. Trussell, D. W. Hand, K. J. Howe, and G. Tchobanoglous.Water Treatment: Principles and Design . 2nd ed. Hoboken, NJ: John Wiley & Sons, 2005, p. 881.Typical properties of filter media used in rapid filters*PROPERTY UNIT GARNET LLMENITE SAND ANTHRACITE GAC Effective Size, ES mm 0.2 - 0.4 0.2 - 0.4 0.4 - 0.8 0.8 - 2.0 0.8 - 2.0 Uniformity Coefficient,UC UC 1.3 - 1.7 1.3 - 1.7 1.3 - 1.7 1.3 - 1.7 1.3 - 2.4 Density, �� g/mL 3.6 - 4.2 4.5 - 5.0 2.65 1.4 - 1.8 1.3 - 1.7Porosity, � % 45 - 58 Not available 40 - 43 47 - 52 Notavailable Hardness Moh 6.5 -7.5 5.6 7 2 - 3 Low* = Not AvailableFigure by MIT OCW.Adapted from: MWH, J. C. Crittenden, R. R. Trussell, D. W. Hand, K. J. Howe, and G. Tchobanoglous. Water Treatment: Principles and Design. 2nd ed. Hoboken, NJ: John Wiley & Sons, 2005, p. 882.Figure by MIT OCW.Adapted from: Binnie, C., M. Kimber, and G. Smethurst. Basic Water Treatment. 3rd ed. Cambridge, UK: Royal Society of Chemistry, 2002.10010-110-210-3 10-4 10-510-610-8 10-7 10-6 10-5 10-4Sedimentation �� = 2650 kg/m 3Sedimentation �� = 1050 kg/m 3Sum 2 Sum 1Interceptionc = 0.5 mm, v = 5 m/h, o C)Particle Diameter, mDiffusionInfluence of Particle Size and Density on Filtration Transport Efficiency (d and T = 25T r a n s p o r t E f f i c i e n c y Figure by MIT OCW.Adapted from: MWH, J. C. Crittenden, R. R. Trussell, D. W. Hand, K. J. Howe, and G. Tchobanoglous.Water Treatment: Principles and Design . 2nd ed. Hoboken, NJ: John Wiley & Sons, 2005, p. 912.Figure by MIT OCW. Adapted from: Yao, K.-M., M. T. Habibian, and C. R. O'Melia. "Water and Waste Water Filtration: Concepts and Applications." Environmental Science & Technology 5, no. 11 (November 1971): 1105-1112.Figure by MIT OCW.Adapted from: O'Melia, C. R., and J. Y. Shin. Removal of particles using dual media filtration: modeling and experimental studies." Water Science and Technology: Water Supply 1, no. 4, (2001): 73-79.Figure by MIT OCW.Adapted from: Binnie, C., M. Kimber, and G. Smethurst. Basic Water Treatment. 3rd ed. Cambridge, UK: Royal Society of Chemistry, 2002.。
水处理专业英语 整理学习资料
水处理专业英语2020．02．17词汇：1.淡水fresh water释：含盐量小于500mg/L的水。
Salt content of water less than 500mg / L.2.水质water quality释：在给水排水工程中，水的物理、化学、生物学等方面的性质。
In water supply and drainage engineering, the physical, chemical and biological properties of water.3.格栅bar screen释：一种栅条形的隔污设备，用以拦截水中较大尺寸的漂浮物或其他杂物。
A grid-shaped pollution isolation device, which is used for intercepting larger-sized floating objects or other debris in water.4．曝气aeration释：水与气体接触，进行溶氧或散除水中溶解性气体和挥发性物质的过程。
The process of dissolving oxygen or removing dissolved gases and volatile substances when water and gas are in contact with each other5. 沉淀sedimentation释：利用重力沉降作用去除水中杂物的过程。
The process of removing impurities in water by gravity sedimentation.6．澄清clarification释：通过与高浓度沉渣层的接触而去除水中杂物的过程。
The process of removing impurities in water by contact with a high concentration sediment layer.7．氯化chlorination释：在水中投氯或含氯氧化物方法消灭病原体的过程。
《物理化学》的中英文翻译
《物理化学》的中英文翻译第一篇：《物理化学》的中英文翻译复习《物理化学》过程中，顺便整理了专业名词的翻译，大家凑合着，依我看，简单的会考汉译英，复杂的会考英译汉。
不管怎么样，中文英文背过最好。
如果有错误，赶紧的，说。
1多相系统 heterogeneous system2自由度degree of freedom3相律 phase rule4独立组分数 number of independent component5凝聚系统 condensed system6三相点 triple point7超临界流体 supercritical fluid8超临界流体萃取supercritical fluid extraction9超临界流体色谱supercritical fluid chromatography10泡点 bubbling point11露点dew point12杠杆规则 level rule13连结线 tie line14部分蒸馏（分馏）fractional distillation15缔合分子 associated molecule16最低恒沸点 minimum azeotropic point17最低恒沸混合物low-boiling azeotrope18无水乙醇(绝对乙醇)absolute ethyl alcohol19最高恒沸点maximum azeotropic point20会溶点 consolute point21共轭层 conjugate layer22烟碱 nicotine23蒸汽蒸馏 steam distillation24步冷曲线 cooling curve25热分析法 thermal analysis26低共熔点 eutectic point27低共熔混合物eutectic mixture28异成分熔点 incongruent melting point29转熔温度 peritectic tempreture30固溶体 solid solution31退火 annealing32淬火 quenching33区域熔炼 zone melting34分凝系数 fractional coagulation coefficient35褶点 plait point36等温会溶点 isothermal consolute point37双节点溶解度曲线 binodal solubility cueve38一（二）级相变first(second)order phase transition39超流体 super fluid40顺磁体 paramagnetic substance41铁磁体 ferromagnetic substance第二篇：中英文翻译蓄电池 battery 充电 converter 转换器 charger开关电器Switch electric 按钮开关Button to switch 电源电器Power electric 插头插座 Plug sockets第三篇：中英文翻译Fundamentals This chapter describes the fundamentals of today’s wireless communications.First a detailed description of the radio channel and its modeling are presented, followed by the introduction of the principle of OFDM multi-carrier transmission.In addition, a general overview of the spread spectrum technique, especially DS-CDMA, is given and examples of potential applications for OFDM and DS-CDMA areanalyzed.This introduction is essential for a better understanding of the idea behind the combination of OFDM with the spread spectrum technique, which is briefly introduced in the last part of this chapter.1.1 Radio Channel Characteristics Understanding the characteristics of the communications medium is crucial for the appropriate selection of transmission system architecture, dimensioning of its components, and optimizing system parameters, especially since mobile radio channels are considered to be the most difficult channels, since they suffer from many imperfections like multipath fading, interference, Doppler shift, and shadowing.The choice of system components is totally different if, for instance, multipath propagation with long echoes dominates the radio propagation.Therefore, an accurate channel model describing the behavior of radio wave propagation in different environments such as mobile/fixed and indoor/outdoor is needed.This may allow one, through simulations, to estimate and validate the performance of a given transmission scheme in its several design phases.1.1.1 Understanding Radio Channels In mobile radio channels(see Figure 1-1), the transmitted signal suffers from different effects, which are characterized as follows: Multipath propagation occurs as a consequence of reflections, scattering, and diffraction of the transmitted electromagnetic wave at natural and man-made objects.Thus, at the receiver antenna, a multitude of waves arrives from many different directions with different delays, attenuations, and phases.The superposition of these waves results in amplitude and phase variations of the composite received signal.Doppler spread is caused by moving objects in the mobile radio channel.Changes in the phases and amplitudes of the arriving waves occur which lead to time-variant multipathpropagation.Even small movements on the order of the wavelength may result in a totally different wave superposition.The varying signal strength due to time-variant multipath propagation is referred to as fast fading.Shadowing is caused by obstruction of the transmitted waves by, e.g., hills, buildings, walls, and trees, which results in more or less strong attenuation of the signal pared to fast fading, longer distances have to be covered to significantly change the shadowing constellation.The varying signal strength due to shadowing is called slow fading and can be described by a log-normal distribution [36].Path loss indicates how the mean signal power decays with distance between transmitter and receiver.In free space, the mean signal power decreases with the square of the distance between base station(BS)and terminal station(TS).In a mobile radio channel, where often no line of sight(LOS)path exists, signal power decreases with a power higher than two and is typically in the order of three to five.Variations of the received power due to shadowing and path loss can be efficiently counteracted by power control.In the following, the mobile radio channel is described with respect to its fast fading characteristic.1.1.2 Channel Modeling The mobile radio channel can be characterized by the time-variant channel impulse response h(τ , t)or by the time-variant channel transfer function H(f, t), which is the Fourier transform of h(τ, t).The channel impulse response represents the response of the channel at time t due to an impulse applied at time t −τ.The mobile radio channel is assumed to be a wide-sense stationary random process, i.e., the channel has a fading statistic that remains constant over short periods of time or small spatial distances.In environments with multipath propagation, the channel impulseresponse is composed of a large number of scattered impulses received over Np different paths，Whereand ap, fD,p, ϕp, and τp are the amplitude, the Doppler frequency, the phase, and the propagation delay, respectively, associated with path p, p = 0,..., Np −1.The assigned channel transfer function isThe delays are measured relative to the first detectable path at the receiver.The Doppler Frequencydepends on the velocity v of the terminal station, the speed of light c, the carrier frequency fc, and the angle of incidence αp of a wave assigned to path p.A channel impulse response with corresponding channel transfer function is illustrated in Figure 1-2.The delay power density spectrum ρ(τ)that characterizes the frequency selectivity of the mobile radio channel gives the average power of the channel output as a function of the delay τ.The mean delay τ , the root mean square(RMS)de lay spread τRMS and the maximum delay τmax are characteristic parameters of the delay power density spectrum.The mean delay isWhereFigure 1-2 Time-variant channel impulse response and channel transfer function with frequency-selective fading is the power of path p.The RMS delay spread is defined as Similarly, the Doppler power density spectrum S(fD)can be defined that characterizes the time variance of the mobile radio channel and gives the average power of the channel output as a function of the Doppler frequency fD.The frequency dispersive properties of multipath channels are most commonly quantified by the maximum occurring Doppler frequency fDmax and the Doppler spread fDspread.The Doppler spread is the bandwidth of theDoppler power density spectrum and can take on values up to two times |fDmax|, i.e.，1.1.3Channel Fade Statistics The statistics of the fading process characterize the channel and are of importance for channel model parameter specifications.A simple and often used approach is obtained from the assumption that there is a large number of scatterers in the channel that contribute to the signal at the receiver side.The application of the central limit theorem leads to a complex-valued Gaussian process for the channel impulse response.In the absence of line of sight(LOS)or a dominant component, the process is zero-mean.The magnitude of the corresponding channel transfer functionis a random variable, for brevity denoted by a, with a Rayleigh distribution given byWhereis the average power.The phase is uniformly distributed in the interval [0, 2π].In the case that the multipath channel contains a LOS or dominant component in addition to the randomly moving scatterers, the channel impulse response can no longer be modeled as zero-mean.Under the assumption of a complex-valued Gaussian process for the channel impulse response, the magnitude a of the channel transfer function has a Rice distribution given byThe Rice factor KRice is determined by the ratio of the power of the dominant path to thepower of the scattered paths.I0 is the zero-order modified Bessel function of first kind.The phase is uniformly distributed in the interval [0, 2π].1.1.4Inter-Symbol(ISI)and Inter-Channel Interference(ICI)The delay spread can cause inter-symbol interference(ISI)when adjacent data symbols overlap and interfere with each other due to differentdelays on different propagation paths.The number of interfering symbols in a single-carrier modulated system is given by For high data rate applications with very short symbol duration Td < τmax, the effect of ISI and, with that, the receiver complexity can increase significantly.The effect of ISI can be counteracted by different measures such as time or frequency domain equalization.In spread spectrum systems, rake receivers with several arms are used to reduce the effect of ISI by exploiting the multipath diversity such that individual arms are adapted to different propagation paths.If the duration of the transmitted symbol is significantly larger than the maximum delay Td τmax, the channel produces a negligible amount of ISI.This effect is exploited with multi-carrier transmission where the duration per transmitted symbol increases with the number of sub-carriers Nc and, hence, the amount of ISI decreases.The number of interfering symbols in a multi-carrier modulated system is given byResidual ISI can be eliminated by the use of a guard interval(see Section 1.2).The maximum Doppler spread in mobile radio applications using single-carrier modulation is typically much less than the distance between adjacent channels, such that the effect of interference on adjacent channels due to Doppler spread is not a problem for single-carrier modulated systems.For multi-carrier modulated systems, the sub-channel spacing Fs can become quite small, such that Doppler effects can cause significant ICI.As long as all sub-carriers are affected by a common Doppler shift fD, this Doppler shift can be compensated for in the receiver and ICI can be avoided.However, if Doppler spread in the order of several percent of the sub-carrier spacing occurs, ICI may degrade the system performance significantly.T oavoid performance degradations due to ICI or more complex receivers with ICI equalization, the sub-carrier spacing Fs should be chosen assuch that the effects due to Doppler spread can be neglected(see Chapter 4).This approach corresponds with the philosophy of OFDM described in Section 1.2 and is followed in current OFDM-based wireless standards.Nevertheless, if a multi-carrier system design is chosen such that the Doppler spread is in the order of the sub-carrier spacing or higher, a rake receiver in the frequency domain can be used [22].With the frequency domain rake receiver each branch of the rake resolves a different Doppler frequency.1.1.5Examples of Discrete Multipath Channel Models Various discrete multipath channel models for indoor and outdoor cellular systems with different cell sizes have been specified.These channel models define the statistics of the 5 discrete propagation paths.An overview of widely used discrete multipath channel models is given in the following.COST 207 [8]: The COST 207 channel models specify four outdoor macro cell propagation scenarios by continuous, exponentially decreasing delay power density spectra.Implementations of these power density spectra by discrete taps are given by using up to 12 taps.Examples for settings with 6 taps are listed in Table 1-1.In this table for several propagation environments the corresponding path delay and power profiles are given.Hilly terrain causes the longest echoes.The classical Doppler spectrum with uniformly distributed angles of arrival of the paths can be used for all taps for simplicity.Optionally, different Doppler spectra are defined for the individual taps in [8].The COST 207 channel models are based on channel measurements with a bandwidth of 8–10 MHz in the 900-MHz band used for 2Gsystems such as GSM.COST 231 [9] and COST 259 [10]: These COST actions which are the continuation of COST 207 extend the channel characterization to DCS 1800, DECT, HIPERLAN and UMTS channels, taking into account macro, micro, and pico cell scenarios.Channel models with spatial resolution have been defined in COST 259.The spatial component is introduced by the definition of several clusters with local scatterers, which are located in a circle around the base station.Three types of channel models are defined.The macro cell type has cell sizes from 500 m up to 5000 m and a carrier frequency of 900 MHz or 1.8 GHz.The micro cell type is defined for cell sizes of about 300 m and a carrier frequency of 1.2 GHz or 5 GHz.The pico cell type represents an indoor channel model with cell sizes smaller than 100 m in industrial buildings and in the order of 10 m in an office.The carrier frequency is 2.5 GHz or 24 GHz.COST 273: The COST 273 action additionally takes multi-antenna channel models into account, which are not covered by the previous COST actions.CODIT [7]: These channel models define typical outdoor and indoor propagation scenarios for macro, micro, and pico cells.The fading characteristics of the various propagation environments are specified by the parameters of the Nakagami-m distribution.Every environment is defined in terms of a number of scatterers which can take on values up to 20.Some channel models consider also the angular distribution of the scatterers.They have been developed for the investigation of 3G system proposals.Macro cell channel type models have been developed for carrier frequencies around 900 MHz with 7 MHz bandwidth.The micro and pico cell channel type models have been developed for carrier frequencies between 1.8 GHz and 2 GHz.The bandwidths of the measurements are in the range of 10–100 MHz for macro cells and around 100 MHz for pico cells.JTC [28]: The JTC channel models define indoor and outdoor scenarios by specifying 3 to 10 discrete taps per scenario.The channel models are designed to be applicable for wideband digital mobile radio systems anticipated as candidates for the PCS(Personal Communications Systems)common air interface at carrier frequencies of about 2 GHz.UMTS/UTRA [18][44]: Test propagation scenarios have been defined for UMTS and UTRA system proposals which are developed for frequencies around 2 GHz.The modeling of the multipath propagation corresponds to that used by the COST 207 channel models.HIPERLAN/2 [33]: Five typical indoor propagation scenarios for wireless LANs in the 5 GHz frequency band have been defined.Each scenario is described by 18discrete taps of the delay power density spectrum.The time variance of the channel(Doppler spread)is modeled by a classical Jake’s spectrum with a maximum terminal speed of 3 m/h.Further channel models exist which are, for instance, given in [16].1.1.6Multi-Carrier Channel Modeling Multi-carrier systems can either be simulated in the time domain or, more computationally efficient, in the frequency domain.Preconditions for the frequency domain implementation are the absence of ISI and ICI, the frequency nonselective fading per sub-carrier, and the time-invariance during one OFDM symbol.A proper system design approximately fulfills these preconditions.The discrete channel transfer function adapted to multi-carrier signals results inwhere the continuous channel transfer function H(f, t)is sampled in time at OFDM symbol rate s and in frequency at sub-carrier spacing Fs.The durations is the total OFDM symbol duration including the guardinterval.Finally, a symbol transmitted onsub-channel n of the OFDM symbol i is multiplied by the resulting fading amplitude an,i and rotated by a random phase ϕn,i.The advantage of the frequency domain channel model is that the IFFT and FFT operation for OFDM and inverse OFDM can be avoided and the fading operation results in one complex-valued multiplication per sub-carrier.The discrete multipath channel models introduced in Section 1.1.5 can directly be applied to(1.16).A further simplification of the channel modeling for multi-carrier systems is given by using the so-called uncorrelated fading channel models.1.1.6.1Uncorrelated Fading Channel Models for Multi-Carrier Systems These channel models are based on the assumption that the fading on adjacent data symbols after inverse OFDM and de-interleaving can be considered as uncorrelated [29].This assumption holds when, e.g., a frequency and time interleaver with sufficient interleaving depth is applied.The fading amplitude an,i is chosen from a distribution p(a)according to the considered cell type and the random phase ϕn,I is uniformly distributed in the interval [0,2π].The resulting complex-valued channel fading coefficient is thus generated independently for each sub-carrier and OFDM symbol.For a propagation scenario in a macro cell without LOS, the fading amplitude an,i is generated by a Rayleigh distribution and the channel model is referred to as an uncorrelated Rayleigh fading channel.For smaller cells where often a dominant propagation component occurs, the fading amplitude is chosen from a Rice distribution.The advantages of the uncorrelated fading channel models for multi-carrier systems are their simple implementation in the frequency domain and the simple reproducibility of the simulation results.1.1.7Diversity The coherence bandwidth of amobile radio channel is the bandwidth over which the signal propagation characteristics are correlated and it can be approximated byThe channel is frequency-selective if the signal bandwidth B is larger than the coherence bandwidth.On the other hand, if B is smaller than , the channel is frequency nonselective or flat.The coherence bandwidth of the channel is of importance for evaluating the performance of spreading and frequency interleaving techniques that try to exploit the inherent frequency diversity Df of the mobile radio channel.In the case of multi-carrier transmission, frequency diversity is exploited if the separation of sub-carriers transmitting the same information exceeds the coherence bandwidth.The maximum achievable frequency diversity Df is given by the ratio between the signal bandwidth B and the coherence bandwidth，The coherence time of the channel is the duration over which the channel characteristics can be considered as time-invariant and can be approximated byIf the duration of the transmitted symbol is larger than the coherence time, the channel is time-selective.On the other hand, if the symbol duration is smaller than , the channel is time nonselective during one symbol duration.The coherence time of the channel is of importance for evaluating the performance of coding and interleaving techniques that try to exploit the inherent time diversity DO of the mobile radio channel.Time diversity can be exploited if the separation between time slots carrying the same information exceeds the coherence time.A number of Ns successive time slots create a time frame of duration Tfr.The maximum time diversity Dt achievable in one time frame is given by the ratio between the duration of a timeframe and the coherence time, A system exploiting frequency and time diversity can achieve the overall diversityThe system design should allow one to optimally exploit the available diversity DO.For instance, in systems with multi-carrier transmission the same information should be transmitted on different sub-carriers and in different time slots, achieving uncorrelated faded replicas of the information in both dimensions.Uncoded multi-carrier systems with flat fading per sub-channel and time-invariance during one symbol cannot exploit diversity and have a poor performance in time and frequency selective fading channels.Additional methods have to be applied to exploit diversity.One approach is the use of data spreading where each data symbol is spread by a spreading code of length L.This, in combination with interleaving, can achieve performance results which are given forby the closed-form solution for the BER for diversity reception in Rayleigh fading channels according to [40] Whererepresents the combinatory function，and σ2 is the variance of the noise.As soon as the interleaving is not perfect or the diversity offered by the channel is smaller than the spreading code length L, or MCCDMA with multiple access interference is applied,(1.22)is a lower bound.For L = 1, the performance of an OFDM system without forward error correction(FEC)is obtained, 9which cannot exploit any diversity.The BER according to(1.22)of an OFDM(OFDMA, MC-TDMA)system and a multi-carrier spread spectrum(MC-SS)system with different spreading code lengths L is shown in Figure 1-3.No other diversity techniques are applied.QPSK modulation is used for symbol mapping.The mobile radio channel is modeled as uncorrelatedRayleigh fading channel(see Section 1.1.6).As these curves show, for large values of L, the performance of MC-SS systems approaches that of an AWGN channel.Another form of achieving diversity in OFDM systems is channel coding by FEC, where the information of each data bit is spread over several code bits.Additional to the diversity gain in fading channels, a coding gain can be obtained due to the selection of appropriate coding and decoding algorithms.中文翻译 1基本原理这章描述今日的基本面的无线通信。
水处理英语介绍作文
水处理英语介绍作文Water Treatment。
Water treatment is the process of purifying water to make it safe for consumption and other uses. It involves various methods and technologies to remove impurities and contaminants from water. The goal is to ensure that the water meets certain quality standards and is free from harmful substances.One common method of water treatment is filtration. This involves passing water through a filter to remove suspended solids, such as dirt, sand, and debris. Filtration helps to improve the clarity and appearance of water, making it visually appealing. It also helps to remove larger particles that can cause clogging or damage to pipes and equipment.Another important aspect of water treatment is disinfection. This is done to kill or inactivatemicroorganisms, such as bacteria, viruses, and parasites, that may be present in water. Disinfection can be achieved through various methods, including the use of chemical disinfectants like chlorine or ultraviolet (UV) radiation. It is essential to disinfect water to prevent waterborne diseases and ensure public health.In addition to filtration and disinfection, water treatment may also involve the use of chemical coagulants and flocculants. These chemicals help to remove fine particles and colloidal matter from water by causing them to clump together and settle. Coagulation and flocculation are important steps in water treatment as they improve the efficiency of filtration and remove substances that can affect water quality and taste.Water treatment is not only important for drinking water, but also for various industrial processes. Many industries rely on water for their operations, and it is crucial to treat the water to meet the specific requirements of each industry. For example, in the manufacturing industry, water treatment is necessary toremove impurities that can affect the quality of products or damage equipment.Overall, water treatment plays a vital role in ensuring the availability of clean and safe water for various purposes. It helps to protect public health, preserve the environment, and support sustainable development. With the increasing demand for water and the growing concerns about water pollution, effective water treatment becomes more important than ever. By implementing proper water treatment processes and technologies, we can ensure that everyone has access to clean and safe water.。
水与废水物化处理原理与工艺
水与废水物化处理原理与工艺英文回答：Water and wastewater physicochemical treatmentprinciples and processes are essential for ensuring clean and safe water supplies and proper management of wastewater. In this response, I will discuss the principles and processes involved in water and wastewater physicochemical treatment.Water treatment is the process of removing impurities and contaminants from water to make it safe for consumption. The physicochemical treatment methods used in water treatment include coagulation, flocculation, sedimentation, filtration, and disinfection.Coagulation is the process of adding chemicals, such as aluminum sulfate or ferric chloride, to water todestabilize and aggregate the suspended particles. This forms larger particles called flocs. Flocculation involvesgently mixing the coagulated water to enhance the formation of larger flocs. The flocs are then settled out in a process called sedimentation, where the heavier particles settle at the bottom of the water.After sedimentation, the water is subjected tofiltration to remove any remaining suspended particles. Filtration can be done through different media, such as sand, activated carbon, or membranes, depending on thelevel of purification required. Finally, disinfection is carried out to kill any remaining microorganisms in the water. Common disinfection methods include chlorination, UV irradiation, or ozonation.Wastewater treatment, on the other hand, involves the removal of pollutants and contaminants from wastewater before it is released back into the environment. The physicochemical treatment methods used in wastewater treatment include chemical precipitation, adsorption, and advanced oxidation processes.Chemical precipitation involves the addition ofchemicals, such as lime or ferric chloride, to the wastewater to form insoluble precipitates. These precipitates can then be separated from the water through sedimentation or filtration. Adsorption is another method used in wastewater treatment, where activated carbon or other adsorbents are used to adsorb organic and inorganic pollutants from the water.Advanced oxidation processes (AOPs) are used to degrade and remove persistent organic pollutants from wastewater. AOPs involve the generation of highly reactive hydroxyl radicals, which can break down complex organic compounds into simpler and less harmful substances. Examples of AOPs include ozonation, photocatalysis, and electrochemical oxidation.中文回答：水和废水物化处理原理和工艺对于确保清洁和安全的水源以及正确管理废水至关重要。
水处理 英语
水处理英语Water TreatmentWater treatment is a process that involves the cleaning and disinfection of water, making it safe for consumption by humans or animals. There are various steps involved in water treatment, each of which helps to remove contaminants from the water. This article will outline the steps that are involved in water treatment.Step One: ScreeningThe first step in water treatment is screening. During this step, the water is passed through a series of screens that help to remove large debris such as leaves, sticks, and other organic matter. The screens are usually made of metal or plastic and have small openings that allow water to pass through while trapping larger objects. Once the water has been screened, it moves on to the next step of the process.Step Two: Coagulation and FlocculationIn this step, chemicals are added to the water to help remove smaller particles that could not be trapped during screening. The most commonly used chemicals for this purpose are alum, ferric chloride, and polymer. Once the chemicals are added, the water is mixed vigorously, causing the smaller particles to stick together and form larger particles called flocs. These flocs will be removed in the next step.Step Three: SedimentationOnce the flocs have formed, the water is allowed to sit in a large tank called a sedimentation basin. During this time, the flocs settle to the bottom of the tank, and theclear water at the top is transferred to the next step of the process. The settled flocs, also known as sludge, are removed and transferred to a separate tank for further treatment.Step Four: FiltrationThe next step in water treatment is filtration. During this step, water is passed through a series of filters that help to remove any remaining particles that may have made it through the previous steps. The filters are made of sand, gravel, and activated charcoal, and are specifically designed to trap smaller particles that were not removed during coagulation and sedimentation.Step Five: DisinfectionThe final step in water treatment is disinfection. During this step, chemicals such as chlorine and ozone are added to the water to kill any remaining bacteria, viruses, or other pathogens that may be present. These chemicals are added in trace amounts that are safe for consumption by humans or animals.In conclusion, water treatment is a critical process that helps to ensure the safety of the water we consume. The steps outlined in this article are essential for removing contaminants from water and making it safe for consumption. As our population continues to grow, the need for clean and safe water will become more significant, and the importance of water treatment will continue to increase.。
水处理专业英语阅读1WaterPollutionandPollutants
1 WaterPollut ion and Pollut antsThe relati onshi p betwee n pollut ed waterand diseas e was firmly establ ished with the choler a epidem ic of 1854 in London, Englan d. Protec tionof public health, the origin al purpos e of pollut ion contro l, contin ues to be the primar y object ive in many areas. Howeve r, preser vatio n of waterresour ces, protec tionof fishin g areas,and mainte nance of recrea tiona l waters are additi onalconcer ns today.Waterpollut ion proble ms intens ified follow ing WorldWar II when dramat ic increa ses in urbandensit y and indust riali zatio n occurr ed. Concer n over waterpollut ion reache d a peak in the mid-sevent ies.Waterpollut ion is an imprec ise term that reveal s nothin g abouteither the type of pollut ing materi al or its source. The way we deal with the wasteproble m depend s upon whethe r the contam inant s are oxygen demand ing, algaepromot ing, infect ious,toxic,or simply unsigh tly. Pollut ion of our waterresour ces can occurdirect ly from seweroutfal ls or indust rialdischa rges(pointsource s) or indire ctlyfrom air pollut ion or agricu ltura l or urbanrunoff (nonpoi nt source s).Chemic allypure wateris a collec tionof H2O molecu les—nothin g else. Such a substa nce is not foundin nature—not in wild stream s or lakes,not in clouds or rain, not in fallin g snow, nor in the polarice caps. Very pure watercan be prepar ed in the labora torybut only with consid erabl e diffic ulty. Wateraccept s and holdsforeig n matter.Munici pal wastew ater,also called sewage, is a comple x mixtur e contai ningwater(usuall y over 99 percen t) togeth er with organi c and inorga nic contam inant s, both suspen ded and dissol ved. The concen trati on of thesecontam inant s is normal ly very low and is expres sed in mg/L, that is, millig ramsof contam inant per literof the mixtur e. This is a weight-to-volume ratioused to indica te concen trati ons of consti tuent s in water, wastew ater,indust rialwastes, and otherdilute soluti ons.Microo rgani sms.Wherev er thereis suitab le food, suffic ientmoistu re, and an approp riate temper ature, microo rgani sms will thrive. Sewage provid es an idealenviro nment for a vast arrayof microb es, primar ily bacter ia, plus some viruse s and protoz oa. Most of thesemicroo rgani sms in wastew aterare harmle ss and can be employ ed in biolog icalproces ses to conver t organi c matter to stable end produc ts. Howeve r, sewage may also contai n pathog ens from the excret a of people with infect iousdiseas es that can be transm itted by contam inate d water.Waterb ornebacter ial diseas es such as choler a, typhoi d, and tuberc ulosi s, viraldiseas es such as infect ioushepati tis, and the protoz oan-caused dysent ery, whileseldom a proble m now in develo ped countr ies, are stilla threat whereproper ly treate d wateris not availa ble for public use. Testsfor the few pathog ens that mightbe presen t are diffic ult and time consum ing, and standa rd practi ce is to test for othermore plenti ful organi ama that are always presen t (in the billio ns) in the intest inesof warm-bloode d animal s, includ ing humans.Solids. The totalsolids (organi c plus inorga nic) in wastew aterare, by defini tion, the residu es afterthe liquid portio n has been evapor atedand the remain der driedto a consta nt weight at 103℃. Differ entia tionbetwee n dissol ved solids and undiss olved, that is, suspen ded, solids are accomp lishe d by evapor ating filter ed and unfilt eredwastew atersample s. The differ encein weight betwee n the two driedsample s indica tes the suspen ded solids conten t. To furthe r catego rizethe residu es, they are held at 550℃for 15 minute s. The ash remain ing is consid eredto repres ent inorga nic solids and the loss of volati le matter to be a measur e of the organi c conten t Suspen ded solids (SS) and volati le suspen ded solids (VSS) are the most useful. SS and BOD (bioche mical oxygen demand) are used as measur es of wastew aterstreng th and proces s perfor mance. VSS can be an indica tor of the organi c conten t of raw wastes and can also provid ea measur e of the active microb ial popula tionin biolog icalproces ses.Inorga nic consti tuent s. The common inorga nic consti tuent s of wastew aterinclud e:1. Chlori des and sulpha tes. Normal ly presen t in waterand in wastes from humans.2. Nitrog en and phosph orous . In theirvariou s forms(organi c and inorga nic) in wastes from humans, with additi onalphosph orous from deterg ents.3. Carbon atesand bicarb onate s. Normal ly presen t in waterand wastes as calciu m and magnes ium salts.4. Toxicsubsta nces. Arseni c, cyanid e, and heavymetals such as Cd, Cr, Cu, Hg, Ph, and Zn are toxicinorga nicswhichmay be foundin indust rialwastes.In additi on to thesechemic al consti tuent s, the concen trati on of dissol ved gases,especi allyoxygen, and the hydrog en ion concen trati on expres sed as pH are otherparame tersof intere st in wastew ater.Organi c matter.Protei ns and carboh ydrat e consti tute90 percen t of the organi c matter in domest ic sewage. The source s of thesebiodeg radab le contam inant s includ e excret a and urinefrom humans; food wastes from sinks; soil and dirt from bathin g; washin g, and launde ring; plus variou s soaps, deterg ents, and othercleani ng produc ts.Variou s parame tersare used as a measur e of the organi c streng th of wastew ater. One method is basedon the amount of organi c carbon(totalorgani c carbon, or TOC) presen t in the waste. TOC is determ inedby measur ing the amount of CO2 produc ed when the organi c carbon in the sample is oxidiz ed by a strong oxidiz er and compar ing it with the amount in a standa rd of knownTOC.Most of the othercommon method s are basedon the amount of oxygen requir ed to conver t the oxidiz ablemateri al to stable end produc ts. Sincethe oxygen used is propor tiona l to theoxidiz ablemateri al presen t, it serves as a relati ve measur e of wastew aterstreng th. The two method s used most freque ntlyto determ ine the oxygen requir ement s of wastew aterare the COD and BOD tests.The COD. or chemic al oxygen demand, of the wastew ateris the measur ed amount of oxygen needed to chemic allyoxidiz e the organi cs presen t; the BOD. or bioche mical oxygen demand, is the measur ed amount of oxygen requir ed by acclim atedmicroo rgani sms to biolog icall y degrad e the organi c matter in the wastew ater.BOD is the most import ant parame ter in waterpollut ion contro l. It is used as a measur e of organi c pollut ion, as a basisfor estima tingthe oxygen needed for biolog icalproces ses, and as an indica tor of proces s perfor mance.The amount of organi c matter in wateror wastew atercan be measur ed direct ly (as TOC, for exampl e), hut this doesn’ttelluswhethe r the organi cs are biodeg radab le or not. To measur e the amount of biodeg radab le organi cs, we use an indire ct method in whichwe measur e the amount of oxygen used by a growin g microb ial popula tionto conver t (oxidiz e) organi c matter to CO2 and H2O in a closed system. The oxygen consum ed. or bioche mical oxygen demand (BOD). is propor tiona l to the organi c matter conver ted, and theref ore BOD is a relati ve measur e of the biolog icall y degrad ableorgani c matter presen t in the system. Becaus e biolog icaloxidat ion contin ues indefi nitel y, the test for ultima te BOD has been arbitr arily limite d to 20 days, when perhap s 95 percen t or more of the oxygen requir ement has been met. Even this period, howeve r, is too long to make measur ement of BOD useful, so a five-day test, BOD5, carrie d out at 20℃, has become standa rd. The rate of the BOD reacti on depend s on the type of wastepresen t and the temper ature and is assume d to vary direct ly with the amount of organi c matter (organi c carbon) presen t.单词表。
- 1、下载文档前请自行甄别文档内容的完整性，平台不提供额外的编辑、内容补充、找答案等附加服务。
- 2、"仅部分预览"的文档,不可在线预览部分如存在完整性等问题,可反馈申请退款(可完整预览的文档不适用该条件!)。
- 3、如文档侵犯您的权益，请联系客服反馈,我们会尽快为您处理(人工客服工作时间：9:00-18:30)。
Physical-chemical treatment ofwater and wastewaterTopic 1●Course descriptionPrinciples of treatment for removing contaminants from drinking water and municipal wastewater ;includes air stripping, coagulation and flocculation, sedimentation, air flotation, filtration, disinfection, oxidation, membrane processes, water softening, and carbon adsorption.●Water quality regulation●Water characteristicsMicrobiological contaminants:a)Coliform bacteriab)More resistant microbesc)Protozoad)VirusesSynthetic organic chemicals(SOCs):a)Disinfection by-products(DBPs): THMs, HAAsb)Industrial contaminants: VOCsc)Agricultural contaminantsInorganic chemicals(IOCs):a)Ground water contaminants: Heavy metal, radioactive wastesb)Plumbing systems: Pb, Cuc)Disinfectant residuals●Processes selectionConsiderations:1)Contaminants removal2)Utility capability3)Source water quality4)Costs5)Reliability6)Environmental capability7)Existing conditions8)Distribution system water quality9)Process flexibility●Fundamental principles1)Mass balance2)Reaction kinetics3)Reactor design4)Aquatic chemistry: Acid-base chemistry/Precipitation/Oxidation-reductionAim at:a)Facilitating separations (转移)b)Achieving destruction (转化)●Material Balance●Reactor Theorya)Mixed Batch Reactor(MBR) –混合式反应器b)Continuously (Completely) Stirred Tank Reactor(CSTR) –连续搅拌式反应器c)Plug Flow Reactor(PFR) –推流式反应器●MBRa)Well-mixedb)Uniform composition in all substances and conditionsc)Constant volumed)No flow in or out●CSTRa)Well-mixedb)Uniform composition in all substances and conditionsc)With same flow in or out●PFRa)Uniform longitudinal velocity profileb)Transverse well-mixingc)No longitudinal mixingd)With same flow in or out●Fundamental of reaction kineticsGlossaryUnit operations-单元操作(physical forces) ; Unit processes-单元过程(chemical reactions); Acidity-酸度; Alkalinity-碱度; Bases Coefficient- ; Equilibrium constant-平衡常数; ppm-百万分率; ppb-十亿分率;Physical-chemical treatment ofwater and wastewaterTopic 2 Basics of Water and Wastewater●WaterLake/ river/ reservoir/ groundwater●Wastewatera)Sanitary wastewater（生活废水）b)Non-sanitary wastewater（非生活废水）c)Storm sewage（暴雨污水）●Constituents in water and wastewatera)Physical characteristicsTurbidity(NTU)/ Color(CU)/ Taste(TTN)/ Odor(TON)/ Temperatureb)Chemical characteristicsOrganicBOD (Biological Oxygen Demand)/COD (Chemical Oxygen Demand)/TOC (Total Organic Carbon)/Surfactants: Detergents/VOC (Volatile Organic Compounds)/Fat/ Oils/ Waxes/ GreaseInorganicAnion: Choloride (Cl-)/ Fluoride(F-)/ Nitrate(NO3-)/ Sulfate(S2-)Cation: Sodium(Na)/ Iron(Fe)/ Manganese(Mn)/ Lead(Pb) /Copper(Cu)/ Zinc(Zn)OthersPhAcidity and alkalinityNitrogenPhosphorousPriority pollutants(优先控制污染物)Toxic metal and nonmetal ions●Constituer 构成TS (total solids)/TFS (total fixed solids)/ TVS (total volatile solids)/FSS (fixed suspended solids)----TSS(total suspended solids)----- VSS(volatile suspended solids) FDS (fixed dissolved solids)-------TDS(total dissolves solids)------VDS(volatile dissolves solids)●Other Important Terms1)BOD/COD/TOC/TN/TP/TSS2)Solubility Product(溶度积)3)Chemical Equilibrium(化学平衡)4)Henry’s Law Constant(亨利常数)5)DO●Indicator MicroorganismServing as a surrogate to indicate the water quality with respect to the fecal contamination or relative quantities of all forms of pathogens.a)Fecal Pollutant Originb)Indicator OrganismsEscherichia coli/ Fecal coliform/ Total coliformc)Numeration(计数方法):Membrane Filtration Technique●Measurement…●CalculationHardnessAlkalinityPhysical-chemical treatment ofwater and wastewaterTopic 3 Typical Processes for Water Treatment●Water EngineeringTasks:a)Removal of particlesb)Removal of pathogen to prevent waterborne diseasesc)Removal of chemical cotaminantsd)Control of taste and odorGoals:a)BOD51-5mg/Lb)TN <1mg N/Lc)TP <0.5mg P/L●Management of Water ResourcesSource selectionsMajor Sources: River/ Lake/ reservoir/ Groundwater/ Sea water●River WaterQuality:a)Fluctuates in time and location;b)Usually has a high turbidity, large number of bacteria, and a low hardness;c)May have overgrowth of algae generating unpleasant flavors (smells & tastes) andcolor.●EutrophicationEutrophication often occurs in closed water bodies such as shallow tidal rivers, lakes, reservoirs, sea bays because of limited dilution capacity resulting in nutrients accumulation in the mud.Cause:a)Death of fishes due to release of toxicants from a algae;b)Shortage of dissolved oxygen during night-time as algae consume a great deal ofoxygen by algal respiration;c)Unpleasant flavors such as bad taste and smell and high tubidity.Deal with: below 1mg N/L & 0.5mg P/L●Water Treatment & Supply Systems for River WaterMajor impurities:large & small sized debris, fine particles, ammonia, algae, dissolved organic matter…System:River →Pumping →Plain sedimentation →coagulation →Flocculation →Sedimentation →Filtration →Disinfection →Pumping →Storage →Neighborhood●Lake/ Reservoir Water TreatmentMajor impurities:SS & TDS lower than river waterQuality:Clear than river water because of the sedimentation effect.Quantity:It also varies in seasons.System:Lake →Pumping →Aeration/ Prechlorination/ Preoxidation →coagulation →Flocculation →Sedimentation →Filtration →Disinfection →Pumping →Storage →Neighborhood●Ground Water/ Well Water TreatmentMajor impurities:Heavy metal, chemical & biological pollutants.Hardness：Ca & MgSystem:Well →Aeration →Softening →Filtration →Disinfection →Add Fluoride →Storage →Neighborhood●Other Water Treatment Processesa)Softeningb)Ion Exchangec)Reverse Osmosis 反渗透d)Activated Carbon AdsorptionPhysical-chemical treatment ofwater and wastewaterTopic 4 Overview of Sewage Treatment●Terminology◆Composition-构成; Constituents-成分; Contaminants-污染物;Pollutants-污染物；Impurities-杂质; Nutrient-营养物;◆Point sources-点源; Non-point sources-非点源; Effluent-流出; Influent-流入;◆Reclamation-再生; Recycling-回收利用; Repurification-再净化;Reuse-重新使用◆Sludge-污泥; Solids-固体; Biosolid-生物固体;●Parameters of wastewaterBOD5/DO/COD/TDS/TP/TN/Fecal coliform●Effluent Standardsa)Established from a stand view of “best available technology”b)Consider environmental or purification capacity of a water receiving bodyc)Depend on usage of a receiving body and types of treatment methods●Treatment levela)Preliminaryb)Primaryc)Advanced primaryd)Secondarye)Secondary with nutrient removalf)Consider environmental or purification capacity of a water receiving bodyg)Advanced●Typical Sewage Treatment SystemRaw Waste →Bar Screen →Grit Chamber →Primary Sedimentation →Biological Treatment →Secondary Sedimentation →Advanced Treatment →Disinfection →Receiving Water Body●Types of sewage treatment processesa)Mechanical treatmentb)Biological treatmentc)Advanced treatment●Removal of constituentsa)Suspended solidsScreening/ Grit removal/ Sedimentation/ High-rate clarification/ Flotation/Chemical precipitation/ Depth filtration/ Surface filtrationb)Biodegradable organics (可生物降解的有机物)Aerobic suspended growth variations/ Aerobic attached growth variations/Anaerobic suspended growth variations/Anaerobic attached growth variations/Lagoon variations/ Physical-chemical systems/ Chemical oxidation/Advanced oxidation/ Membrane filtrationc)NutrientsNitrogen: Chemical oxidation/Suspended-growth nitrification(硝化) and denitrification(反硝化) /Fixed-film nitrification and denitrification variations/Air stripping/ Ion exchangePhosphorus: Chemical treatment/ Biological phosphorus removalNitrogen & phosphorus: Biological nutrient removal variationsd)PathogenChlorine compounds/ Chlorine dioxide/ Ozone/ Ultraviolet(UV) radiatione)Colloidal and dissolved solidsMembrane/ Chemical treatment/ Carbon adsorption/ Ion exchangef)Volatile organic compoundsAir stripping/ Carbon adsorption/ Advanced oxidation/g)OdorsChemical scrubbers/ Carbon adsorption/ Biofilters/ Compost filters●Primary Treatmenta)Preliminary treatment: Bar screen/ Grit chamber/ Comminuterb)Primary Sedimentation●Biological Treatment (secondary)a)Activated Sludgeb)Trickling Filterc)Rotating Biological Contactor●Disinfection●Oil and Grease Control●Advanced Treatmenta)Nitrogen removal: Ammonia stripping/ Nitrification/ Denitrificationb)Phosphorus removal: Chemical precipitation/ Biological Processesc)For water reused)Depend on usage: filtration/ GACWordsNitrosomonas - 亚硝化单胞菌; Nitrobacter –硝化菌; Denitrifer –脱氮菌Physical-chemical treatment of water and wastewaterTopic 5 Preliminary Unit Operations●Unit operations and processesUnit operationsa)Flow meters流量计b)Pumpingc)Screeningd)Mixinge)Flocculationf)Setting and flotationg)Filtrationh)Adsorptioni)Aeration and stripping j)Membrane Unit processesa)Softeningb)Neutralization中和c)Stabilizationd)Chemical precipitatione)Phosphorus removalf)Iron and manganese removalg)Coagulationh)Ion exchangei)Disinfectionj)Oxidation-reduction●Flow Metersa)Coriolis flowmetersb)Turbine flowmeters 涡轮流量计c)Differential pressure flowmeters 压差流量计d)Variable area flowmeters 转子流量计●WeirsWeir is an obstruction that is used to back up a flowing stream of liquid.●ScreeningA unit operation that separates materials into different sizes .Coarse screens(6-150mm)/ Micro screens(<0.5um)/ Fine screens(<6mm)a)Screenings retained on the coarse (>12mm)Debris, rocks, branches, pieces of lumbers, leaves, paper, plastics, rags, organics…b)Screenings retained on the fine(>6mm)Small rags, razor blades, grid, feces…●Coarse solids reductiona)Comminutor 磨碎机b)Macerator 碎渣机c)Grinder 研磨机●Flow equalizationA method used to overcome the operational problems caused by flowrate variations, toimprove the performance of the downstream processes, to reduce the size and cost of downstream treatment facilities.●Grit removalGrit chambers are designed to remove grit, consisting of sand, gravel, cinders, or other heavy solid materials that have subsiding velocities or specific gravities substantially greater than those of the organic putrescible solid in wastewater.Horizontal-flow grit chambers/ Aerated grit chambers/ Vortex-type grit chambers●PumpingA unit operation that is used to move fluid from one point to another.●Mixingwater and wastewaterTopic 6 Aeration ( Air Stripping )●MechanismExchange of gases from air phase to water phase (absorption) or from water phase to air phase (stripping) due to the displacement of the system from equilibrium partitioning.Unsaturation/absorption Saturation/equilibrium Supersaturation/desorption●Two-Film TheoryIt states that gas transfer is governed by the resistance of the gas and liquid films surrounding the interface.●Gas Transfer TheoryTherefore, the extent of displacement of the system from equilibrium provides the driving force that governs the gas (mass) transfer.●Major Types of Aeration MeansDiffused (or bubble) aerationSurface (mechanical) aerationGravity aerators: Cascade/ Inclined/ Tower/ Stack Tray/ Cascade Tower/ Spray Aeratorwater and wastewater Topic 7 Coagulation/ Flocculation●Colloidal StabilityRepulsion force: Electrostatic potentialAttraction force: Van der Waals force●Coagulation Theorya)Iron layer compressionb)Adsorption and charge neutralizationc)Sweep coagulation●Hydrolyzed Trivalent Alum Ions●Action of hydrolyzed metal ions1)Ionic layer compression2)Adsorption and charge neutralization3)Adsorption and interparticle bridging4)Enmeshment in sweep flocwater and wastewaterTopic 8 Settling (or Sedimentation, clarification)●BasicsPhysical removal of dense/heavy suspended solids from water by exposing the water to relatively quiescent conditions to allow settleable solids to be removed by the action of the force of gravity.settling tank (basin) / sedimentation tank (basin) / clarifier●Factors affecting particle settling——Particle density——Particle concentrationDilute suspension / Concentrated suspension——Surface flocculent natureDiscrete particles / Flocculating particles● 4 typesDiscrete Settling / Flocculating SettlingZone Settling / Compression Settling●Discrete SettlingType I settling is characterized by settling of individual particles without interaction with adjacent particles.The shape, size and density of the particles remain unchanged during settling.Examples of Type I Settlings : Settling of sand, grit etc.Application : Design of primary settling tank, grit chamber●Flocculating SettlingSettling flocculating particles in dilute suspension:——Dilute suspension --- no interference of the velocity field between particles. ——Flocculating particles --- aggregation of particles causing continually changing in size and shape of particles for settling.——The flocs will increase their size --- speed up settling●Variations of the types of sedimentation tank——Horizontal-flow settling tank——Upflow clarifier——High rate (inclined plate) settlers——Reactor (solid contact) clarifierPhysical-chemical treatment ofwater and wastewaterTopic 15 MembraneFeedwater (f)Q f=feedwater flowrate C f=feedwater concentration P f=feedwater pressurePermeate (f)Q P=permeate flowrateC P=permeateconcentrationP P=permeate pressureConcentrate (f)Q C=concentrate flowrateC C=concentrate concentration P C=concentrate pressure ClassificationMicrofiltration (MF)--------微滤Ultrafiltration (UF)----------超滤Nanofiltration (NF)----------纳滤Reverse osmosis (RO)----反渗透Dialysis--------------------------渗析Electrodialysis (ED)-------电渗析Membrane foulingHow to control：☐Pretreatment of the feed water——To reduce TSS and bacterial content☐Membrane backflushing——To eliminate the accumulated material☐Chemical cleaning of the membrane——To remove the constituents that can not be removed by backflushing。