APS digestion托福听力原文翻译及问题答案

APS digestion托福听力原文翻译及问题答案

一、APS digestion托福听力原文：

NARRATOR:Listen to part of a lecture in an environmental engineering class.MALE PROFESSOR:At the end of yesterday's class,we were discussing landfills and the hundreds of millions of tons of everyday garbage which are deposited into them each year in the United States.It's a growing problem!Quite simply,we are running out of space to put our garbage.And this is especially true for solid organic waste:food scraps from home or food processing plants,waste from farms,that sort of thing.

Did you know that two thirds of the waste sitting in our landfills is organic material?We have government recycling programs for materials like plastics,glass and metal,yet widespread solutions for organic waste materials haven't really been addressed in the United States.I think this is just asking for trouble in the future.So today I want to talk about a technology that offers a potential solution to the problem—anaerobic Phased Solids digestion,or APS digestion.First of all,what does anaerobic mean?Anyone?

FEMALE STUDENT:Without oxygen?MALE PROFESSOR:Correct!APS digestion uses anaerobic bacteria,ones that thrive in the absence of oxygen,to consume,to break down organic material.MALE STUDENT:Excuse me.Professor.Um...those anaerobic bacteria you are talking about...well,aren't anaerobic bacteria also used in waste water treatment plants?MALE PROFESSOR:Yes.In fact,they are.Would you like to explain this to the class?MALE STUDENT:Sure!So when waste water is treated,one of the byproducts is a thick liquid called sludge.And aren't anaerobic bacteria used to break down the sludge?MALE PROFESSOR:That's right.Anaerobic bacteria have been used in waste water treatment for decades.MALE STUDENT:So how is this technology different?MALE PROFESSOR:Good question.The anaerobic digestion systems used in waste water plants are designed to treat sludge,not solids.Now,in the past,researchers have attempted to treat solid organic waste with that same equipment.But there was always a problem.In order to process the solid waste,the kind we find in landfills,you had to pretreat the solids to turn them into sludge.

First,by breaking the material apart mechanically into small particles and then adding a lot of water until you got a kind of thick,soupy mix that the equipment could handle.But that extra step took time and required a lot of energy.FEMALE STUDENT:That sounds like it would cost a lot.MALE PROFESSOR:That's right.But APS digestion is designed specifically to handle solid waste.So it is much more cost-effective.The new technology processes organic waste in two phases.Remember,APS stands for Anaerobic Phased Solids digestion.

First,the waste material is loaded into a large,closed container,along with different types of anaerobic bacteria.The bacteria break the solids down into acids and hydrogen gas.The hydrogen is extracted and the remaining acids are transferred into a different container for the second phase of the process.There another type of bacteria converts the acids into methane gas.FEMALE STUDENT:Aren't hydrogen and methane gas bad for the environment though?MALE PROFESSOR:The answer in this case is no,because they don't escape into the atmosphere.The gases are captured and can be burned to produce electricity,which saves a lot of money and ultimately decreases our need for fuels like petroleum and coal,which are not only expensive but are also polluting.MALE STUDENT:So organic waste from landfills could be processed this way?MALE PROFESSOR:It is certainly one possibility.And APS digestion systems are very versatile.They can be installed just about anywhere.See,anaerobic digestion systems used at waste water treatment plants are huge tanks that hold thousands of gallons of waste water.But the APS containers are small enough to be set up on site,where the waste is generated,like at food processing plants or on farms.

So garbage doesn't have to be transported long distances.As a matter of fact,a couple of universities successfully set up demonstration projects.They collected food scraps from dining halls and local restaurants and process them in APS facilities.Not only did the university save money,we are also learning even more about the APS process.What is the next step forward?Well,APS digestion uses several different types of anaerobic bacteria,right?So what are the most efficient bacteria in the process?If researchers can figure that out,the highest performing bacteria mix for a system could be determined.Ultimately the goal would be to grow enough of these particular bacteria to support large-scale commercial APS systems.

二、APS digestion托福听力中文翻译：

旁白：请听一节环境工程课的部分讲座。男教授：在昨天的课结束时，我们讨论了垃圾填埋场和美国每年堆积在垃圾填埋场中的数亿吨日常垃圾。这是一个日益严重的问题！很简单，我们已经没有空间放垃圾了。这对于固体有机废物尤其如此：来自家庭或食品加工厂的食物残渣，来自农场的废物，诸如此类。

你知道我们的垃圾填埋场中有三分之二的垃圾是有机材料吗？我们有政府对塑料、玻璃和金属等材料的回收计划，但在美国还没有真正解决有机废料的广泛解决方案。我认为这只是在将来自找麻烦。因此，今天我想谈谈一种技术，它为厌氧阶段固体消化或APS消化提供了一种潜在的解决方案。首先，无氧是什么意思？任何人

女学生：没有氧气？男教授：对！APS消化利用厌氧细菌，即在缺氧条件下生长的细菌，消耗和分解有机物质。男学生：对不起，教授。嗯…你所说的那些厌氧菌…嗯，废水处理厂不也使用厌氧菌吗？男教授：是的。事实上，他们是。你想向全班同学解释一下吗？男学生：当然！因此，当废水被处理时，其中一种副产物是一种叫做污泥的粘稠液体。厌氧菌不是用来分解污泥的吗？男教授：没错。厌氧菌已用于废水处理数十年。男学生：那么这项技术有什么不同呢？男教授：好问题。废水处理厂中使用的厌氧消化系统旨在处理污泥，而不是固体。现在，在过去，研究人员试图用同样的设备处理固体有机废物。但总有一个问题。为了处理我们在垃圾填埋场发现的固体废物，你必须对固体进行预处理，把它们变成污泥。

首先，通过机械地将材料分解成小颗粒，然后加入大量水，直到你得到一种设备可以处理的粘稠的混合物。但这一额外步骤需要时间和大量能量。女学生：听起来要花很多钱。男教授：没错。但APS消化是专门为处理固体废物而设计的。因此它更具成本效益。新技术分两个阶段处理有机废物。记住，APS代表厌氧阶段固体消化。

首先，将废物与不同类型的厌氧细菌一起装入一个大型封闭容器中。细菌将固体分解成酸和氢气。提取氢并将剩余酸转移到用于该方法第二阶段的不同容器中。在那里，另一种细菌将酸转化为甲烷气体。女学生：氢气和甲烷气体对环境有害吗？男教授：在这种情况下，答案是否定的，因为它们不会逃逸到大气中。这些气体被捕获并燃烧发电，这节省了大量资金，并最终减少了我们对石油和煤炭等燃料的需求，这些燃料不仅昂贵，而且污染严重。男学生：那么垃圾填埋场的有机废物可以这样处理？男教授：这当然是一种可能性。APS消化系统非常通用。它们可以安装在任何地方。看，废水处理厂使用的厌氧消化系统是巨大的水箱，可以容纳数千加仑的废水。但APS容器足够小，可以在产生废物的现场安装，如食品加工厂或农场。

所以垃圾不需要长距离运输。事实上，有几所大学成功地建立了示范项目。他们从餐厅和当地餐馆收集食物残渣，并在APS设施中处理。这所大学不仅节省了资金，我们还学习了更多关于APS过程的知识。下一步是什么？APS消化使用几种不同类型的厌氧细菌，对吗？那么在这个过程中最有效的细菌是什么呢？如果研究人员能够找到答案，那么就可以确定一个系统中性能最高的细菌组合。最终的目标是培养足够数量的这些特殊细菌，以支持大规模商业APS系统。

三、APS digestion托福听力问题：

Q1:1.What is the lecture mainly about?

A.A new use for methane gas produced in landfills

B.Environmental regulations regarding the management of organic wastes

C.Removing bacteria from landfills and wastewater treatment plants

D.A potentially useful technology for managing organic wastes

Q2:2.What is the professor's opinion about the use of landfills to manage solid organic waste?

A.Landfills should be expanded to accommodate more types of waste.

B.Landfills are not a suitable long-term solution for solid organic waste disposal.

C.Landfills should be built farther away from population centers.

D.Landfills would be an effective means of recycling solid organic waste from farms.

Q3:3.What does the professor imply about processing solid organic waste in equipment designed for processing wastewater?

A.It is an economical way to process solid waste.

B.It is practical only for treating large amounts of solid waste.

C.It is not an efficient way to process solid waste.

D.It could reduce the cost of treating wastewater.

Q4:4.What does the professor suggest about methane and hydrogen gas?

A.They have beneficial uses if harnessed and contained.

B.They are destroyed in a later stage of APS processing.

C.They are both extracted during the first phase of APS digestion.

D.They are necessary to activate the anaerobic digestion process.

Q5:5.According to the professor,what are two advantages of APS digestion systems?[Click on 2 answers.]

A.They can eliminate the need to transport the waste material.

B.They can handle both organic and nonorganic waste.

C.They can turn waste into fuel for electrical power generation.

D.They can be monitored efficiently from one central location.

Q6:6.What does the professor say is a promising focus for future research into APS digestion systems?

A.Trying to find a way to reduce the size of the APS containers

B.Trying to set up a demonstration project with a university

C.Determining whether food scraps from restaurants can be used in the system

D.Determining the most efficient combination of anaerobic bacteria

四、APS digestion托福听力答案：

A1:正确答案：D

A2:正确答案：B

A3:正确答案：C

A4:正确答案：A

A5:正确答案：AC

A6:正确答案：D