Unit 10、Unit 12、Unit 13考试内容
句子翻译
1、Pollution of our water resources can occur directly from sewer outfalls or industrial discharges (point sources) or indirectly from air pollution or agricultural or urban runoff (nonpoint sources).
水资源的污染可能是被污水的排放或工业废水的排放直接造成（点源），也可能是被大气污染或农业、城市排水间接造成的（非点源）。
2、Chemically pure water is a collection of H20 molecules—nothing else. Such a substance is not found in nature—not in wild streams or lakes, not in clouds or rain, not in falling snow, nor in the polar ice caps.
化学纯水是水分子的收集（只有水分子）。在自然界是不存在化学纯的水，在天然的溪水或天然湖水里，在云朵或雨水里，在下的雪或在极地的冰箱里都不存在化学纯的水。
3、Suspended solids (SS) and volatile suspended solids (VSS) are the most useful. SS and BOD (biochemical oxygen demand) are used as measures of wastewater strength and process performance.
悬浮固体和挥发性悬浮固体是很有用的两个参数，悬浮固体和生化需氧量是用来测量废水的污染强度和处理性能。
4、BOD is the most important parameter in water pollution control. It is used as a measure of organic pollution，as a basis for estimating the oxygen needed for biological processes, and as an indicator of process performance.
在水污染控制中，生物化学需氧量是很重要的参数。可用来作为表示有机污染的测量方法，可作为估计生物处理时所需的氧量的基础，并可做为处理性能的指示性参数。
5、Water molecules have no memory. and therefore it is silly to talk about the number of times that the water you drink has been polluted and repurified, as if the molecules gradually wore out. All that is important is how pure it is when you drink it.
水分子是没有记忆力的，所以谈论被污染和被净化的饮用水的次数是没意义的，例如分子的逐渐损耗。而当我们饮水的时候到底它有多纯净才是最重要的。
6、When the sewage reaches the treatment plant, it first passes through a series of screens that remove large objects such as rats or grapefruits, and then through a grinding mechanism that reduces any remaining objects to a size small enough to be handled effectively during the remaining treatment period.
当生活污水到达污水处理厂时，它首先通过一系列的滤网以除去如老鼠，葡萄柚似的大物体，和在接下来的处理时期里，通过一架磨碾机以减少剩下的物体的尺寸使其足够小能有效地被处理。
7、The treatment methods available to cope with these troublesome wastes are necessarily specific to the type of pollutant to be removed, and they are generally expensive. A few of these techniques are described below.
用于应付这些麻烦废水的处理方式是必需专门除去这类污染物，而且它们一般很昂贵。如下描述几种这些技术。
8、By bubbling air through water, or by creating contact between air and water by spraying, dissolved iron or manganese (Fe ,Mn ) is oxidized to a less soluble form (Fe ,Mn ), which precipitates out and can be removed in s settling tank or filter.
通过空气气泡进入水中，或通过喷洒引起空气和水接触，溶解性的铁和锰（Fe ,Mn ）被氧化成一种溶解性水的形式（Fe ,Mn ），它们被析出然后能在一个沉淀池或过滤器中被去除。
9、Softening of water is a process that removes hardness, caused by the presence of divalent metallic ions, principally Ca2+and Mg2+. Hardness in water is the result of contact with soil and rock, particularly limestone, in the presence of CO2
水的软化是将水除去硬度的一个过程，硬度的产生由于二价金属离子的存在（尤其是钙离子和镁离子），水的硬化正是由于水与土壤或岩石接触反应的结果，对于在有二氧化碳存在下的石灰石，水的硬化更为明显。
10、Activated Carbon is an extremely adsorbent material used in water treatment to remove organic contaminants. Activated carbon is produced in a two-stage process. First, a suitable base material such as wood, pest, vegetable matter, or bone is carbonized by heating the material in the absence of sir. Then the carbonized material is activated by heating it in the presence of sir, CO2 , or steam to burn off any tars it has and to increase its pore size. Adsorption of gases, liquids, and solids by activated carbon is influenced by the temperature and pH of the water as well 55 the complexity of the organics being removed.
活性炭是一种很好的吸附剂被广泛用于水处理中来除去有机污染物。活性炭的制备要经过两个过程。第一，适合的基本材料例如木头，泥炭块，植物材料，或者在缺少空气中被加热炭化的骨头。然后在存在空气，二氧化碳的情况下，加热这种炭化的物质使其有活性，或者蒸发烧掉其含有的任何焦油来增大它的气孔。用活性炭吸附气体、液体、以及固体的去除效果会受水的温度、pH 值和有机物的复杂性的影响。
11、In reverse osmosis (RO), fresh water is forced through a semipermeable membrane in the direction opposite to that occurring in natural
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4+
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osmosis. Because the membrane removes dissolved salts, the main application for RO has been in desalination. However, the process also removes organic materials, bacteria, and viruses, and its application in water treatment is growing.
反渗透（RO ）是指以自然渗透逆方向通过半透膜的过程。因为渗透膜可以去除了溶解盐，所以反渗透的最主要应用是用于脱盐。然而，这过程中的有机原材料，细菌和病毒也被去除了，所以反渗透在污水处理中的应用还有待进一步发展改进。
段落翻译
Organic matter. Proteins and carbohydrate& constitute 90 percent of the organic matter in domestic sewage. The sources of these biodegradable contaminants include excreta and urine from humans; food wastes form sinks; soil and dirt from bathing; washing, and laundering; plus various soaps, detergents, and other cleaning products.
Various parameters are used as a measure of the organic strength of wastewater. One method is based on the amount of organic carbon (total organic carbon, or TOC) present in the waste. TOC is determined by measuring the amount of CO2 produced when the organic carbon in the sample is oxidized by a strong oxidizer and comparing it with the amount in a standard of known TOC.
Most of the other common methods are based on the amount of oxygen required to convert the oxidizable material to stable end products. Since the oxygen used is proportional to the oxidizable material present, it serves as a relative measure of wastewater strength. The two methods used most frequently to determine the oxygen requirements of wastewater are the CODS and BOD tests. The COD. or chemical oxygen demand, of the wastewater is the measured amount of oxygen needed to chemically oxidize the organics present; the BOD. or biochemical oxygen demand, is the measured amount of oxygen required by acclimated microorganisms to biologically degrade the organic matter in the wastewater.
BOD is the moat important parameter in water pollution control. It is used as a measure of organic pollution. as a basis for estimating The amount of organic matter in water or wastewater can be measured directly (as TOO, for example), hut this doesn’t’ t tell us the oxygen needed for biological processes, and as an indicator of process performance.
whether the organics are biodegradable or not, To measure the amount of biodegradable organics, we use an indirect method in which we measure the amount of oxygen used by a growing microbial population to convert (oxidize) organic matter to CO2 and H20 in a closed system. The oxygen consumed. or biochemical oxygen demand (HOD). is proportional to the organic matter converted, and therefore BOD is a relative measure of the biologically degradable organic matter present in the system. Because biological oxidation continues indefinitely, the test for ultimate BOD has been arbitrarily limited to 20 days. when perhaps 95 percent or more of the oxygen requirement has been met. Even this period, however, is too long to make measurement of BOD useful, so a five-day test. BOD, carried out at 20t. has become standard. The rate of the BOD reaction depends on the type of waste present and the temperature and is assumed to vary directly with the amount of organic matter (organic carbon) present.
有机物 生活污水中的有机物90％是由蛋白质和碳水化合物组成。这些可生物降解的物质包括人类的尿和排泄物、洗涤槽的食物残渣、土和洗澡的脏物、洗衣用水和洗烫水，及各种肥皂、洗洁精和其他清洁产品。
各种指标用来衡量废水中有机物浓度。一种方法是基于废水中的有机碳的总量（即总有机碳TOC ）。总有机碳是由样品中有机碳被强氧化剂氧化成二氧化碳的数量与已知的总有机碳的标准数量的比较所决定的。
常见的另一种方法是根据把氧化物转化成稳定的最终产物所需要的氧气。因为需氧量正比于污水中现存的氧化物，它可以用于废水浓度的相对衡量。通常确定废水需氧量的两种方法是COD （化学需氧量）和BOD （生化需氧量）的测定。化学需氧量，是用化学方法氧化有机物的需氧量。而生化需氧量，是通过适应环境的微生物的以生物的方式降解废水中的有机物的需氧量。
在水污染控制理论中，生化需氧量是最重要的参数。生化需氧量用于测定有机物污染，是评估生物反应需氧量的基础和反应过程的指标。
我们可以直接地测定水或者废水中的有机物含量（例如测定总有机碳），但是这并不能告诉我们有机物是否有被生物降解。为了测定可生物降解的有机物量，我们用一种间接的方法，也就是在一个封闭的系统里，测定将有机物转化（氧化）成二氧化碳和水所用的生长的微生物群的耗氧量。耗用的氧气，或生化需氧量，正比于有机物的转化量。因此，生化需氧量是系统中生物降解有机物的相对衡量。因为生物氧化过程可以无限次地进行，最终生化需氧量的测定被限定为20天，这个时间能够满足95%或以上的微生物氧气需求。但是过程时间过长，致使生化需氧量的测定没有效用。所以一种五天式的测定，即将水样置于20℃的黑暗环境五天，作为生化需氧量的标准。生化需氧量的反应速度取决于存在的废水类型、温度以及假设其随着存在的有机物（有机碳）的数量的变化趋势。 Secondary Treatment
The next series of steps is designed to reduce greatly the dissolved or finely suspended organic matter by some form of accelerated biological action. What is needed for such decomposition is oxygen and organisms and an environment in which both have ready access to the nutrients.
One device for accomplishing this objective is the trickling filter. In this device, long pipes rotate slowly over a bed of stones, distributing the polluted water in continuous sprays. As the water trickles over and around the stones, it offers its nutrients in the presence of air to an abundance of rather unappetizing forms of life.
An alternative technique is the activated sludge process. Here the sewage, after primary treatment, is pumped into an aeration tank, where it is mixed for several hours with air and bacteria-laden sludge. The biological action is similar to that which occurs in the trickling filter. The sludge bacteria metabolize the organic nutrients; the protozoa, as secondary consumers, feed on the bacteria. The treated waters then flow to a sedimentation tank, where the bacteria-laden solids settle out and are returned to the aerator. Some of the sludge must be removed to maintain steady-state conditions. The activated sludge process requires less land space than the trickling filters, and, since it exposes less area to the atmosphere, it does not stink so much.
The effluent from the biological action is still laden with bacteria and is not fit for discharge into open waters, let alone for drinking. Since the microorganisms have done their work, they may now be killed. The final step is therefore a disinfection process. ，usually chlorination, Chlorine gas, injected into the effluent 15 to 30 minutes before its final discharge, can kill more than 99 percent of the harmful bacteria. 二级处理
接下来的一系列步骤，是设计通过加速生化作用的某种形式来较大程度地减少溶解的或微小的悬浮有机物。分解需要氧气和微生物以及一种两者都易接近营养物的环境。达到这个目标的一种装置是滴滤池。这种装置，长管在由岩石填充而成的滤床上缓慢的旋转，通过持续地喷洒来分布这些污水。
另一个技术是活性污泥过程。废水，经过初级处理后，泵到一个混合空气和含有细菌的污泥几个小时的曝气池。生化作用与发生在滴滤池的相似。污泥中的细菌代谢转化成有机氧物；原生虫，作为二级消费者，吃掉细菌。处理过的水流到一个含有细菌的固体沉降的沉淀池去，然后返回到曝气池。某些污泥必须被排放以维持一个稳定的状态。相对滴滤池来说，活性污泥需要占地少的面积，因为它需要曝气较小的面积，没有发出臭味。
生化处理所排放的废水仍然含有细菌，和不适合排放到清洁的水源，更不用说饮用。因为微生物完成其工作，现在就可以杀死他们了。最后一步是消毒过程，一般是加氯。氯气，在最后排放前加入到排水15至30分钟，就可以杀灭99%以上的有害细菌。
Coagulation/flocculation is a chemical-physical procedure whereby particles too small for practical removal by plain sedimentation are destabilized sod clustered together for faster settling. A significant percentage of particulates suspended in water are so small that settling to the bottom of a tank would take days or weeks. These colloidal particles would never settle by plain sedimentation.
Coagulation is s chemical process used to destabilize colloidal particles. The exact mechanism is not well understood, but the general ides is to add a chemical which has positively charged colloids to water containing negatively charged colloids. This will neutralize the negative change on the colloids and thus reduce the tendency for the colloids to repel each other. Rapid mixing for a few seconds is required to disperse the coagulant. Gentle mixing, called flocculation, of the suspension is then undertaken to promote particle contact. This is achieved by mechanical mixing through the use of slowly rotating paddles inside the coagulation/flocculation tank, or by hydraulic mixing which occurs when flow is directed over and around baffles in the tank. Detention time in the coagulation/flocculation tank is usually between 20—40 minutes in tanks 3—4m deep. Through the combined chemical/physical process of coagulation/flocculation, the colloidal particles which would not settle out by plain sedimentation are agglomerated to form larger solids called floe. These appear as fluffy growths of irregular shape that are able to entrap small noncoagulaed particles when settling downward. Aluminum sulfate is the most common coagulant but organic polymers may also be used alone or in combination with alum to improve flocculation. The floe suspension is gently transferred from the coagulation/flocculation tanks to settling tanks or directly to filters where the floes are removed.
混凝/絮凝是一个化学物理过程，那些太小的用普通沉降法不能去除的颗粒具有在这个过程中失去稳定性能成团的特点，从而混凝是使胶体粒子脱稳的化学过程。确切机理并未完全探究清楚，但是总概念是向含有负电荷的水中加入带正电荷的化学物能较快地沉淀。大部分悬浮颗粒太小以至于沉淀到池底需要几天或者几周。甚至这些胶体粒子不能够通过普通沉淀法沉降。 质。其结果是中和水中反粒子从而降低胶体之间相互排斥的趋势。分散混凝剂需要几秒钟的快速混合。悬浮物的慢速混合称为絮凝，这种沉降可以促进粒子直接的接触。并且可以在混凝/絮凝池内通过旋转桨的旋转来实现，或利用水力压力直接在池内折流板周围形成。深度在3~4米之间的混凝/絮凝池的滞留时间是20~40分钟。通过混凝/絮凝联合的化学/物理过程，不能被简单沉降池沉降的胶体颗粒可以聚集形成一种大颗粒状的絮状物。在沉降过程中，将会出现可以捕获微小非凝固态颗粒的不规则形状的毛绒状物质。硫酸铝是最通常的凝结剂，有机聚合物也可以单独作为混凝剂，或者与明矾起来改善絮凝效果。在絮状物被去除的过程中，它一般从混凝/絮凝池转移到沉淀池中，或直接被过滤。
句子翻译
1水资源的污染可能是被污水的排放或工业废水的排放直接造成（点源），也可能是被大气污染或农业、城市排水间接造成的（非点源）。
2化学纯水是水分子的收集（只有水分子）。在自然界是不存在化学纯的水，在天然的溪水或天然湖水里，在云朵或雨水里，在下的雪或在极地的冰箱里都不存在化学纯的水。
3悬浮固体和挥发性悬浮固体是很有用的两个参数，悬浮固体和生化需氧量是用来测量废水的污染强度和处理性能。
4在水污染控制中，生物化学需氧量是很重要的参数。可用来作为表示有机污染的测量方法，可作为估计生物处理时所需的氧量的基础，并可做为处理性能的指示性参数。
5水分子是没有记忆力的，所以谈论被污染和被净化的饮用水的次数是没意义的，例如分子的逐渐损耗。而当我们饮水的时候到底它有多纯净才是最重要的。
6当生活污水到达污水处理厂时，它首先通过一系列的滤网以除去如老鼠，葡萄柚似的大物体，和在接下来的处理时期里，通过一架磨碾机以减少剩下的物体的尺寸使其足够小能有效地被处理。
7用于应付这些麻烦废水的处理方式是必需专门除去这类污染物，而且它们一般很昂贵。如下描述几种这些技术。
8通过空气气泡进入水中，或通过喷洒引起空气和水接触，溶解性的铁和锰（Fe 2+,Mn 2+）被氧化成一种溶解性水的形式（Fe 3+,Mn 4+），它们被析出然后能在一个沉淀池或过滤器中被去除。
9水的软化是将水除去硬度的一个过程，硬度的产生由于二价金属离子的存在（尤其是钙离子和镁离子），水的硬化正是由于水与土壤或岩石接触反应的
Unit10
epidemic 流行的、传染的 algae 海藻、藻类 outfall 出口、排出 sewage 污水、废水
organic 有机的、机体的 microbe 微生物 bacteria 细菌 pathogen 病菌
excreta 排泄物、粪便 oxidizer 氧化剂
acclimate 服水土、适应环境 filter 过滤 degrade 降解
结果，对于在有二氧化碳存在下的石灰石，水的硬化更为明显。
10活性炭是一种很好的吸附剂被广泛用于水处理中来除去有机污染物。活性炭的制备要经过两个过程。第一，适合的基本材料例如木头，泥炭块，植物材料，或者在缺少空气中被加热炭化的骨头。然后在存在空气，二氧化碳的情况下，加热这种炭化的物质使其有活性，或者蒸发烧掉其含有的任何焦油来增大它的气孔。用活性炭吸附气体、液体、以及固体的去除效果会受水的温度、pH 值和有机物的复杂性的影响。
11反渗透（RO ）是指以自然渗透逆方向通过半透膜的过程。因为渗透膜可以去除了溶解盐，所以反渗透的最主要应用是用于脱盐。然而，这过程中的有机原材料，细菌和病毒也被去除了，所以反渗透在污水处理中的应用还有待进一步发展改进。 段落翻译
有机物 生活污水中的有机物90％是由
蛋白质和碳水化合物组成。这些可生物降解的物质包括人类的尿和排泄物、洗涤槽的食物残渣、土和洗澡的脏物、洗衣用水和洗烫水，及各种肥皂、洗洁精和其他清洁产品。
各种指标用来衡量废水中有机物浓度。一
种方法是基于废水中的有机碳的总量（即总有机碳TOC ）。总有机碳是由样品中有机碳被强氧化剂氧化成二氧化碳的数量与已知的总有机碳的标准数量的比较所决定的。
常见的另一种方法是根据把氧化物转化
成稳定的最终产物所需要的氧气。因为需氧量正比于污水中现存的氧化物，它可以用于废水浓度的相对衡量。通常确定废水需氧量的两种方法是COD （化学需氧量）和BOD （生化需氧量）的测定。化学需氧量，是用化学方法氧化有机物的需氧量。而生化需氧量，是通过适应环境的微生物的以生物的方式降解废水中的有机物的需氧量。 Unit12
purification 净化、纯化 colloidal 胶体的、乳化的 debris 有机残渣、腐质、残骸 sanitary 有关卫生的、清洁的 waterborne 水中的
human excrement人类排泄物 overflow 溢出
activated sludge活性污泥 coagulation 凝固、絮凝 sedimentation 沉淀、沉积 ozone 臭氧
reverse osmosis反向渗透 membrane 膜
在水污染控制理论中，生化需氧量是最重
池。某些污泥必须被排放以维持一个稳定的状态。要的参数。生化需氧量用于测定有机物污染，是评相对滴滤池来说，活性污泥需要占地少的面积，因估生物反应需氧量的基础和反应过程的指标。
为它需要曝气较小的面积，没有发出臭味。
我们可以直接地测定水或者废水中的有
生化处理所排放的废水仍然含有细菌，和
机物含量（例如测定总有机碳），但是这并不能告诉不适合排放到清洁的水源，更不用说饮用。因为微我们有机物是否有被生物降解。为了测定可生物降生物完成其工作，现在就可以杀死他们了。最后一解的有机物量，我们用一种间接的方法，也就是在步是消毒过程，一般是加氯。氯气，在最后排放前一个封闭的系统里，测定将有机物转化（氧化）成加入到排水15至30分钟，就可以杀灭99%以上的二氧化碳和水所用的生长的微生物群的耗氧量。耗有害细菌。
用的氧气，或生化需氧量，正比于有机物的转化量。 因此，生化需氧量是系统中生物降解有机物的相对
衡量。因为生物氧化过程可以无限次地进行，最终混凝/絮凝是一个化学物理过程，那些太小的用普通生化需氧量的测定被限定为20天，这个时间能够满沉降法不能去除的颗粒具有在这个过程中失去稳定足95%或以上的微生物氧气需求。但是过程时间过性能成团的特点，从而能较快地沉淀。大部分悬浮长，致使生化需氧量的测定没有效用。所以一种五颗粒太小以至于沉淀到池底需要几天或者几周。甚天式的测定，即将水样置于20℃的黑暗环境五天，至这些胶体粒子不能够通过普通沉淀法沉降。 作为生化需氧量的标准。生化需氧量的反应速度取 混凝是使胶体粒子脱稳的化学过程。确切决于存在的废水类型、温度以及假设其随着存在的机理并未完全探究清楚，但是总概念是向含有负电有机物（有机碳）的数量的变化趋势。
荷的水中加入带正电荷的化学物质。其结果是中和 水中反粒子从而降低胶体之间相互排斥的趋势。分
散混凝剂需要几秒钟的快速混合。悬浮物的慢速混二级处理
合称为絮凝，这种沉降可以促进粒子直接的接触。接下来的一系列步骤，是设计通过加速生
并且可以在混凝/絮凝池内通过旋转桨的旋转来实化作用的某种形式来较大程度地减少溶解的或微小现，或利用水力压力直接在池内折流板周围形成。的悬浮有机物。分解需要氧气和微生物以及一种两深度在3~4米之间的混凝/絮凝池的滞留时间是者都易接近营养物的环境。达到这个目标的一种装20~40分钟。通过混凝/絮凝联合的化学/物理过程，置是滴滤池。这种装置，长管在由岩石填充而成的不能被简单沉降池沉降的胶体颗粒可以聚集形成一滤床上缓慢的旋转，通过持续地喷洒来分布这些污种大颗粒状的絮状物。在沉降过程中，将会出现可水。
以捕获微小非凝固态颗粒的不规则形状的毛绒状物另一个技术是活性污泥过程。废水，经过
质。硫酸铝是最通常的凝结剂，有机聚合物也可以初级处理后，泵到一个混合空气和含有细菌的污泥单独作为混凝剂，或者与明矾起来改善絮凝效果。几个小时的曝气池。生化作用与发生在滴滤池的相在絮状物被去除的过程中，它一般从混凝/絮凝池转似。污泥中的细菌代谢转化成有机氧物；原生虫，移到沉淀池中，或直接被过滤。
作为二级消费者，吃掉细菌。处理过的水流到一个含有细菌的固体沉降的沉淀池去，然后返回到曝气
Unit13
screening 隔离
turbidity 浊度、浑浊性 at the tap自来水、饮水
plain sedimentation普通沉淀法 agglomerate 使聚集、成团 alum 铝
ultraviolet light紫外线 aeration 曝气 fixture 装置
limestone 石灰石
semipermeable 半渗透 desalination 脱盐
Unit 10、Unit 12、Unit 13考试内容
句子翻译
1、Pollution of our water resources can occur directly from sewer outfalls or industrial discharges (point sources) or indirectly from air pollution or agricultural or urban runoff (nonpoint sources).
水资源的污染可能是被污水的排放或工业废水的排放直接造成（点源），也可能是被大气污染或农业、城市排水间接造成的（非点源）。
2、Chemically pure water is a collection of H20 molecules—nothing else. Such a substance is not found in nature—not in wild streams or lakes, not in clouds or rain, not in falling snow, nor in the polar ice caps.
化学纯水是水分子的收集（只有水分子）。在自然界是不存在化学纯的水，在天然的溪水或天然湖水里，在云朵或雨水里，在下的雪或在极地的冰箱里都不存在化学纯的水。
3、Suspended solids (SS) and volatile suspended solids (VSS) are the most useful. SS and BOD (biochemical oxygen demand) are used as measures of wastewater strength and process performance.
悬浮固体和挥发性悬浮固体是很有用的两个参数，悬浮固体和生化需氧量是用来测量废水的污染强度和处理性能。
4、BOD is the most important parameter in water pollution control. It is used as a measure of organic pollution，as a basis for estimating the oxygen needed for biological processes, and as an indicator of process performance.
在水污染控制中，生物化学需氧量是很重要的参数。可用来作为表示有机污染的测量方法，可作为估计生物处理时所需的氧量的基础，并可做为处理性能的指示性参数。
5、Water molecules have no memory. and therefore it is silly to talk about the number of times that the water you drink has been polluted and repurified, as if the molecules gradually wore out. All that is important is how pure it is when you drink it.
水分子是没有记忆力的，所以谈论被污染和被净化的饮用水的次数是没意义的，例如分子的逐渐损耗。而当我们饮水的时候到底它有多纯净才是最重要的。
6、When the sewage reaches the treatment plant, it first passes through a series of screens that remove large objects such as rats or grapefruits, and then through a grinding mechanism that reduces any remaining objects to a size small enough to be handled effectively during the remaining treatment period.
当生活污水到达污水处理厂时，它首先通过一系列的滤网以除去如老鼠，葡萄柚似的大物体，和在接下来的处理时期里，通过一架磨碾机以减少剩下的物体的尺寸使其足够小能有效地被处理。
7、The treatment methods available to cope with these troublesome wastes are necessarily specific to the type of pollutant to be removed, and they are generally expensive. A few of these techniques are described below.
用于应付这些麻烦废水的处理方式是必需专门除去这类污染物，而且它们一般很昂贵。如下描述几种这些技术。
8、By bubbling air through water, or by creating contact between air and water by spraying, dissolved iron or manganese (Fe ,Mn ) is oxidized to a less soluble form (Fe ,Mn ), which precipitates out and can be removed in s settling tank or filter.
通过空气气泡进入水中，或通过喷洒引起空气和水接触，溶解性的铁和锰（Fe ,Mn ）被氧化成一种溶解性水的形式（Fe ,Mn ），它们被析出然后能在一个沉淀池或过滤器中被去除。
9、Softening of water is a process that removes hardness, caused by the presence of divalent metallic ions, principally Ca2+and Mg2+. Hardness in water is the result of contact with soil and rock, particularly limestone, in the presence of CO2
水的软化是将水除去硬度的一个过程，硬度的产生由于二价金属离子的存在（尤其是钙离子和镁离子），水的硬化正是由于水与土壤或岩石接触反应的结果，对于在有二氧化碳存在下的石灰石，水的硬化更为明显。
10、Activated Carbon is an extremely adsorbent material used in water treatment to remove organic contaminants. Activated carbon is produced in a two-stage process. First, a suitable base material such as wood, pest, vegetable matter, or bone is carbonized by heating the material in the absence of sir. Then the carbonized material is activated by heating it in the presence of sir, CO2 , or steam to burn off any tars it has and to increase its pore size. Adsorption of gases, liquids, and solids by activated carbon is influenced by the temperature and pH of the water as well 55 the complexity of the organics being removed.
活性炭是一种很好的吸附剂被广泛用于水处理中来除去有机污染物。活性炭的制备要经过两个过程。第一，适合的基本材料例如木头，泥炭块，植物材料，或者在缺少空气中被加热炭化的骨头。然后在存在空气，二氧化碳的情况下，加热这种炭化的物质使其有活性，或者蒸发烧掉其含有的任何焦油来增大它的气孔。用活性炭吸附气体、液体、以及固体的去除效果会受水的温度、pH 值和有机物的复杂性的影响。
11、In reverse osmosis (RO), fresh water is forced through a semipermeable membrane in the direction opposite to that occurring in natural
2+
2+
3+
4+
3+
4+
2+
2+
osmosis. Because the membrane removes dissolved salts, the main application for RO has been in desalination. However, the process also removes organic materials, bacteria, and viruses, and its application in water treatment is growing.
反渗透（RO ）是指以自然渗透逆方向通过半透膜的过程。因为渗透膜可以去除了溶解盐，所以反渗透的最主要应用是用于脱盐。然而，这过程中的有机原材料，细菌和病毒也被去除了，所以反渗透在污水处理中的应用还有待进一步发展改进。
段落翻译
Organic matter. Proteins and carbohydrate& constitute 90 percent of the organic matter in domestic sewage. The sources of these biodegradable contaminants include excreta and urine from humans; food wastes form sinks; soil and dirt from bathing; washing, and laundering; plus various soaps, detergents, and other cleaning products.
Various parameters are used as a measure of the organic strength of wastewater. One method is based on the amount of organic carbon (total organic carbon, or TOC) present in the waste. TOC is determined by measuring the amount of CO2 produced when the organic carbon in the sample is oxidized by a strong oxidizer and comparing it with the amount in a standard of known TOC.
Most of the other common methods are based on the amount of oxygen required to convert the oxidizable material to stable end products. Since the oxygen used is proportional to the oxidizable material present, it serves as a relative measure of wastewater strength. The two methods used most frequently to determine the oxygen requirements of wastewater are the CODS and BOD tests. The COD. or chemical oxygen demand, of the wastewater is the measured amount of oxygen needed to chemically oxidize the organics present; the BOD. or biochemical oxygen demand, is the measured amount of oxygen required by acclimated microorganisms to biologically degrade the organic matter in the wastewater.
BOD is the moat important parameter in water pollution control. It is used as a measure of organic pollution. as a basis for estimating The amount of organic matter in water or wastewater can be measured directly (as TOO, for example), hut this doesn’t’ t tell us the oxygen needed for biological processes, and as an indicator of process performance.
whether the organics are biodegradable or not, To measure the amount of biodegradable organics, we use an indirect method in which we measure the amount of oxygen used by a growing microbial population to convert (oxidize) organic matter to CO2 and H20 in a closed system. The oxygen consumed. or biochemical oxygen demand (HOD). is proportional to the organic matter converted, and therefore BOD is a relative measure of the biologically degradable organic matter present in the system. Because biological oxidation continues indefinitely, the test for ultimate BOD has been arbitrarily limited to 20 days. when perhaps 95 percent or more of the oxygen requirement has been met. Even this period, however, is too long to make measurement of BOD useful, so a five-day test. BOD, carried out at 20t. has become standard. The rate of the BOD reaction depends on the type of waste present and the temperature and is assumed to vary directly with the amount of organic matter (organic carbon) present.
有机物 生活污水中的有机物90％是由蛋白质和碳水化合物组成。这些可生物降解的物质包括人类的尿和排泄物、洗涤槽的食物残渣、土和洗澡的脏物、洗衣用水和洗烫水，及各种肥皂、洗洁精和其他清洁产品。
各种指标用来衡量废水中有机物浓度。一种方法是基于废水中的有机碳的总量（即总有机碳TOC ）。总有机碳是由样品中有机碳被强氧化剂氧化成二氧化碳的数量与已知的总有机碳的标准数量的比较所决定的。
常见的另一种方法是根据把氧化物转化成稳定的最终产物所需要的氧气。因为需氧量正比于污水中现存的氧化物，它可以用于废水浓度的相对衡量。通常确定废水需氧量的两种方法是COD （化学需氧量）和BOD （生化需氧量）的测定。化学需氧量，是用化学方法氧化有机物的需氧量。而生化需氧量，是通过适应环境的微生物的以生物的方式降解废水中的有机物的需氧量。
在水污染控制理论中，生化需氧量是最重要的参数。生化需氧量用于测定有机物污染，是评估生物反应需氧量的基础和反应过程的指标。
我们可以直接地测定水或者废水中的有机物含量（例如测定总有机碳），但是这并不能告诉我们有机物是否有被生物降解。为了测定可生物降解的有机物量，我们用一种间接的方法，也就是在一个封闭的系统里，测定将有机物转化（氧化）成二氧化碳和水所用的生长的微生物群的耗氧量。耗用的氧气，或生化需氧量，正比于有机物的转化量。因此，生化需氧量是系统中生物降解有机物的相对衡量。因为生物氧化过程可以无限次地进行，最终生化需氧量的测定被限定为20天，这个时间能够满足95%或以上的微生物氧气需求。但是过程时间过长，致使生化需氧量的测定没有效用。所以一种五天式的测定，即将水样置于20℃的黑暗环境五天，作为生化需氧量的标准。生化需氧量的反应速度取决于存在的废水类型、温度以及假设其随着存在的有机物（有机碳）的数量的变化趋势。 Secondary Treatment
The next series of steps is designed to reduce greatly the dissolved or finely suspended organic matter by some form of accelerated biological action. What is needed for such decomposition is oxygen and organisms and an environment in which both have ready access to the nutrients.
One device for accomplishing this objective is the trickling filter. In this device, long pipes rotate slowly over a bed of stones, distributing the polluted water in continuous sprays. As the water trickles over and around the stones, it offers its nutrients in the presence of air to an abundance of rather unappetizing forms of life.
An alternative technique is the activated sludge process. Here the sewage, after primary treatment, is pumped into an aeration tank, where it is mixed for several hours with air and bacteria-laden sludge. The biological action is similar to that which occurs in the trickling filter. The sludge bacteria metabolize the organic nutrients; the protozoa, as secondary consumers, feed on the bacteria. The treated waters then flow to a sedimentation tank, where the bacteria-laden solids settle out and are returned to the aerator. Some of the sludge must be removed to maintain steady-state conditions. The activated sludge process requires less land space than the trickling filters, and, since it exposes less area to the atmosphere, it does not stink so much.
The effluent from the biological action is still laden with bacteria and is not fit for discharge into open waters, let alone for drinking. Since the microorganisms have done their work, they may now be killed. The final step is therefore a disinfection process. ，usually chlorination, Chlorine gas, injected into the effluent 15 to 30 minutes before its final discharge, can kill more than 99 percent of the harmful bacteria. 二级处理
接下来的一系列步骤，是设计通过加速生化作用的某种形式来较大程度地减少溶解的或微小的悬浮有机物。分解需要氧气和微生物以及一种两者都易接近营养物的环境。达到这个目标的一种装置是滴滤池。这种装置，长管在由岩石填充而成的滤床上缓慢的旋转，通过持续地喷洒来分布这些污水。
另一个技术是活性污泥过程。废水，经过初级处理后，泵到一个混合空气和含有细菌的污泥几个小时的曝气池。生化作用与发生在滴滤池的相似。污泥中的细菌代谢转化成有机氧物；原生虫，作为二级消费者，吃掉细菌。处理过的水流到一个含有细菌的固体沉降的沉淀池去，然后返回到曝气池。某些污泥必须被排放以维持一个稳定的状态。相对滴滤池来说，活性污泥需要占地少的面积，因为它需要曝气较小的面积，没有发出臭味。
生化处理所排放的废水仍然含有细菌，和不适合排放到清洁的水源，更不用说饮用。因为微生物完成其工作，现在就可以杀死他们了。最后一步是消毒过程，一般是加氯。氯气，在最后排放前加入到排水15至30分钟，就可以杀灭99%以上的有害细菌。
Coagulation/flocculation is a chemical-physical procedure whereby particles too small for practical removal by plain sedimentation are destabilized sod clustered together for faster settling. A significant percentage of particulates suspended in water are so small that settling to the bottom of a tank would take days or weeks. These colloidal particles would never settle by plain sedimentation.
Coagulation is s chemical process used to destabilize colloidal particles. The exact mechanism is not well understood, but the general ides is to add a chemical which has positively charged colloids to water containing negatively charged colloids. This will neutralize the negative change on the colloids and thus reduce the tendency for the colloids to repel each other. Rapid mixing for a few seconds is required to disperse the coagulant. Gentle mixing, called flocculation, of the suspension is then undertaken to promote particle contact. This is achieved by mechanical mixing through the use of slowly rotating paddles inside the coagulation/flocculation tank, or by hydraulic mixing which occurs when flow is directed over and around baffles in the tank. Detention time in the coagulation/flocculation tank is usually between 20—40 minutes in tanks 3—4m deep. Through the combined chemical/physical process of coagulation/flocculation, the colloidal particles which would not settle out by plain sedimentation are agglomerated to form larger solids called floe. These appear as fluffy growths of irregular shape that are able to entrap small noncoagulaed particles when settling downward. Aluminum sulfate is the most common coagulant but organic polymers may also be used alone or in combination with alum to improve flocculation. The floe suspension is gently transferred from the coagulation/flocculation tanks to settling tanks or directly to filters where the floes are removed.
混凝/絮凝是一个化学物理过程，那些太小的用普通沉降法不能去除的颗粒具有在这个过程中失去稳定性能成团的特点，从而混凝是使胶体粒子脱稳的化学过程。确切机理并未完全探究清楚，但是总概念是向含有负电荷的水中加入带正电荷的化学物能较快地沉淀。大部分悬浮颗粒太小以至于沉淀到池底需要几天或者几周。甚至这些胶体粒子不能够通过普通沉淀法沉降。 质。其结果是中和水中反粒子从而降低胶体之间相互排斥的趋势。分散混凝剂需要几秒钟的快速混合。悬浮物的慢速混合称为絮凝，这种沉降可以促进粒子直接的接触。并且可以在混凝/絮凝池内通过旋转桨的旋转来实现，或利用水力压力直接在池内折流板周围形成。深度在3~4米之间的混凝/絮凝池的滞留时间是20~40分钟。通过混凝/絮凝联合的化学/物理过程，不能被简单沉降池沉降的胶体颗粒可以聚集形成一种大颗粒状的絮状物。在沉降过程中，将会出现可以捕获微小非凝固态颗粒的不规则形状的毛绒状物质。硫酸铝是最通常的凝结剂，有机聚合物也可以单独作为混凝剂，或者与明矾起来改善絮凝效果。在絮状物被去除的过程中，它一般从混凝/絮凝池转移到沉淀池中，或直接被过滤。
句子翻译
1水资源的污染可能是被污水的排放或工业废水的排放直接造成（点源），也可能是被大气污染或农业、城市排水间接造成的（非点源）。
2化学纯水是水分子的收集（只有水分子）。在自然界是不存在化学纯的水，在天然的溪水或天然湖水里，在云朵或雨水里，在下的雪或在极地的冰箱里都不存在化学纯的水。
3悬浮固体和挥发性悬浮固体是很有用的两个参数，悬浮固体和生化需氧量是用来测量废水的污染强度和处理性能。
4在水污染控制中，生物化学需氧量是很重要的参数。可用来作为表示有机污染的测量方法，可作为估计生物处理时所需的氧量的基础，并可做为处理性能的指示性参数。
5水分子是没有记忆力的，所以谈论被污染和被净化的饮用水的次数是没意义的，例如分子的逐渐损耗。而当我们饮水的时候到底它有多纯净才是最重要的。
6当生活污水到达污水处理厂时，它首先通过一系列的滤网以除去如老鼠，葡萄柚似的大物体，和在接下来的处理时期里，通过一架磨碾机以减少剩下的物体的尺寸使其足够小能有效地被处理。
7用于应付这些麻烦废水的处理方式是必需专门除去这类污染物，而且它们一般很昂贵。如下描述几种这些技术。
8通过空气气泡进入水中，或通过喷洒引起空气和水接触，溶解性的铁和锰（Fe 2+,Mn 2+）被氧化成一种溶解性水的形式（Fe 3+,Mn 4+），它们被析出然后能在一个沉淀池或过滤器中被去除。
9水的软化是将水除去硬度的一个过程，硬度的产生由于二价金属离子的存在（尤其是钙离子和镁离子），水的硬化正是由于水与土壤或岩石接触反应的
Unit10
epidemic 流行的、传染的 algae 海藻、藻类 outfall 出口、排出 sewage 污水、废水
organic 有机的、机体的 microbe 微生物 bacteria 细菌 pathogen 病菌
excreta 排泄物、粪便 oxidizer 氧化剂
acclimate 服水土、适应环境 filter 过滤 degrade 降解
结果，对于在有二氧化碳存在下的石灰石，水的硬化更为明显。
10活性炭是一种很好的吸附剂被广泛用于水处理中来除去有机污染物。活性炭的制备要经过两个过程。第一，适合的基本材料例如木头，泥炭块，植物材料，或者在缺少空气中被加热炭化的骨头。然后在存在空气，二氧化碳的情况下，加热这种炭化的物质使其有活性，或者蒸发烧掉其含有的任何焦油来增大它的气孔。用活性炭吸附气体、液体、以及固体的去除效果会受水的温度、pH 值和有机物的复杂性的影响。
11反渗透（RO ）是指以自然渗透逆方向通过半透膜的过程。因为渗透膜可以去除了溶解盐，所以反渗透的最主要应用是用于脱盐。然而，这过程中的有机原材料，细菌和病毒也被去除了，所以反渗透在污水处理中的应用还有待进一步发展改进。 段落翻译
有机物 生活污水中的有机物90％是由
蛋白质和碳水化合物组成。这些可生物降解的物质包括人类的尿和排泄物、洗涤槽的食物残渣、土和洗澡的脏物、洗衣用水和洗烫水，及各种肥皂、洗洁精和其他清洁产品。
各种指标用来衡量废水中有机物浓度。一
种方法是基于废水中的有机碳的总量（即总有机碳TOC ）。总有机碳是由样品中有机碳被强氧化剂氧化成二氧化碳的数量与已知的总有机碳的标准数量的比较所决定的。
常见的另一种方法是根据把氧化物转化
成稳定的最终产物所需要的氧气。因为需氧量正比于污水中现存的氧化物，它可以用于废水浓度的相对衡量。通常确定废水需氧量的两种方法是COD （化学需氧量）和BOD （生化需氧量）的测定。化学需氧量，是用化学方法氧化有机物的需氧量。而生化需氧量，是通过适应环境的微生物的以生物的方式降解废水中的有机物的需氧量。 Unit12
purification 净化、纯化 colloidal 胶体的、乳化的 debris 有机残渣、腐质、残骸 sanitary 有关卫生的、清洁的 waterborne 水中的
human excrement人类排泄物 overflow 溢出
activated sludge活性污泥 coagulation 凝固、絮凝 sedimentation 沉淀、沉积 ozone 臭氧
reverse osmosis反向渗透 membrane 膜
在水污染控制理论中，生化需氧量是最重
池。某些污泥必须被排放以维持一个稳定的状态。要的参数。生化需氧量用于测定有机物污染，是评相对滴滤池来说，活性污泥需要占地少的面积，因估生物反应需氧量的基础和反应过程的指标。
为它需要曝气较小的面积，没有发出臭味。
我们可以直接地测定水或者废水中的有
生化处理所排放的废水仍然含有细菌，和
机物含量（例如测定总有机碳），但是这并不能告诉不适合排放到清洁的水源，更不用说饮用。因为微我们有机物是否有被生物降解。为了测定可生物降生物完成其工作，现在就可以杀死他们了。最后一解的有机物量，我们用一种间接的方法，也就是在步是消毒过程，一般是加氯。氯气，在最后排放前一个封闭的系统里，测定将有机物转化（氧化）成加入到排水15至30分钟，就可以杀灭99%以上的二氧化碳和水所用的生长的微生物群的耗氧量。耗有害细菌。
用的氧气，或生化需氧量，正比于有机物的转化量。 因此，生化需氧量是系统中生物降解有机物的相对
衡量。因为生物氧化过程可以无限次地进行，最终混凝/絮凝是一个化学物理过程，那些太小的用普通生化需氧量的测定被限定为20天，这个时间能够满沉降法不能去除的颗粒具有在这个过程中失去稳定足95%或以上的微生物氧气需求。但是过程时间过性能成团的特点，从而能较快地沉淀。大部分悬浮长，致使生化需氧量的测定没有效用。所以一种五颗粒太小以至于沉淀到池底需要几天或者几周。甚天式的测定，即将水样置于20℃的黑暗环境五天，至这些胶体粒子不能够通过普通沉淀法沉降。 作为生化需氧量的标准。生化需氧量的反应速度取 混凝是使胶体粒子脱稳的化学过程。确切决于存在的废水类型、温度以及假设其随着存在的机理并未完全探究清楚，但是总概念是向含有负电有机物（有机碳）的数量的变化趋势。
荷的水中加入带正电荷的化学物质。其结果是中和 水中反粒子从而降低胶体之间相互排斥的趋势。分
散混凝剂需要几秒钟的快速混合。悬浮物的慢速混二级处理
合称为絮凝，这种沉降可以促进粒子直接的接触。接下来的一系列步骤，是设计通过加速生
并且可以在混凝/絮凝池内通过旋转桨的旋转来实化作用的某种形式来较大程度地减少溶解的或微小现，或利用水力压力直接在池内折流板周围形成。的悬浮有机物。分解需要氧气和微生物以及一种两深度在3~4米之间的混凝/絮凝池的滞留时间是者都易接近营养物的环境。达到这个目标的一种装20~40分钟。通过混凝/絮凝联合的化学/物理过程，置是滴滤池。这种装置，长管在由岩石填充而成的不能被简单沉降池沉降的胶体颗粒可以聚集形成一滤床上缓慢的旋转，通过持续地喷洒来分布这些污种大颗粒状的絮状物。在沉降过程中，将会出现可水。
以捕获微小非凝固态颗粒的不规则形状的毛绒状物另一个技术是活性污泥过程。废水，经过
质。硫酸铝是最通常的凝结剂，有机聚合物也可以初级处理后，泵到一个混合空气和含有细菌的污泥单独作为混凝剂，或者与明矾起来改善絮凝效果。几个小时的曝气池。生化作用与发生在滴滤池的相在絮状物被去除的过程中，它一般从混凝/絮凝池转似。污泥中的细菌代谢转化成有机氧物；原生虫，移到沉淀池中，或直接被过滤。
作为二级消费者，吃掉细菌。处理过的水流到一个含有细菌的固体沉降的沉淀池去，然后返回到曝气
Unit13
screening 隔离
turbidity 浊度、浑浊性 at the tap自来水、饮水
plain sedimentation普通沉淀法 agglomerate 使聚集、成团 alum 铝
ultraviolet light紫外线 aeration 曝气 fixture 装置
limestone 石灰石
semipermeable 半渗透 desalination 脱盐