2023年全國碩士研究生考試考研英語一試題真題(含答案詳解+作文范文)_第1頁
已閱讀1頁,還剩8頁未讀 繼續(xù)免費閱讀

下載本文檔

版權(quán)說明:本文檔由用戶提供并上傳,收益歸屬內(nèi)容提供方,若內(nèi)容存在侵權(quán),請進行舉報或認領(lǐng)

文檔簡介

1、<p><b>  中文2150字</b></p><p>  生物質(zhì)作為替代燃料用來發(fā)電</p><p><b>  前言</b></p><p>  電能有許多不同的產(chǎn)生來源而且可用不同的方式來生產(chǎn)。然而,各國競相尋找能源,并試圖尋找的無限能源來生產(chǎn)電能。此外,生產(chǎn)電能而使用的礦物燃料,如石油,煤炭等,都會產(chǎn)

2、生一些從能源成本到環(huán)境的污染等重大問題。在上世紀末,工程師們開始尋找新的能源,這些能源既具有與化石燃料相同的優(yōu)點勢外,同時也避免了其弊端。事實上,有一些能源因來自自然而著稱,這就是所謂的可再生能源。之所以稱它是可再生能源,是因為它不能耗盡并且可以重復使用。這種能源有不同種類和不同的形式,例如風能,太陽能,水能,水電能源,生物質(zhì)能等。</p><p>  “在美國,自1973年以來便開始大量利用生物質(zhì),特別是木屑在

3、熱能及電力應用的利用上”。本文將探討利用生物質(zhì)作為電力行業(yè)中使用的替代燃料。文章開頭,將涉及生物質(zhì)的背景和它的歷史來源。其次,將對利用生物質(zhì)能發(fā)電的電廠進行調(diào)查。再次隨后,陳述一些利用生物質(zhì)的優(yōu)點和缺點。最后,一個結(jié)論將總結(jié)全文。</p><p><b>  生物質(zhì)能簡介</b></p><p>  生物質(zhì)是世界上最古老的可再生能源之一。雖然我們一直在使用它,但很少有

4、人知道它的學名。生物質(zhì)學名為活著的物質(zhì),或具體地講,它是在死亡的樹木,樹枝,木材,農(nóng)作物,甚至動物能量存儲能源的轉(zhuǎn)換,從而讓我們可以使用它。例如,“在今天的美國,物質(zhì)燃料的使用范疇,包括木屑,花草殘葉,農(nóng)業(yè)殘留物和城市碎木”。因此,生物質(zhì)能源可在任何時間和地點找到。事實上,如果生物質(zhì)不轉(zhuǎn)換成其它形式的話它將一無是處。因此,如果任何公司想利用生物質(zhì)能作為石油或天然氣的替代能源,就必須收集生物質(zhì)(植物,木材等)并將它在某一地點燃燒,燃燒產(chǎn)生

5、的熱量可用于推動汽輪機發(fā)電。同樣,電廠可以使用生物量在的燃燒中的氣化過程。在這種情況下,將把生物量加熱到極高溫度而產(chǎn)生可燃氣體,可用于推動渦輪旋轉(zhuǎn)從而產(chǎn)生電能。據(jù)加州能源委員會的網(wǎng)頁介紹,加州每年生產(chǎn)約60萬噸的生物質(zhì),這意味著2000兆瓦的電能。事實上,這些能量足以滿足市場需求和約2百萬戶人家使用。雖然生物質(zhì)能源已被使用多年,一些國家一直以來仍把它作為燃料用作發(fā)電。與此相反,一些國家因為其對環(huán)境的負面影響而停止使用。有人說,生物質(zhì)導致

6、了環(huán)境的污染。但是,該能源的益處鼓勵一些企業(yè)使用它,</p><p>  廢棄物發(fā)電 用化石燃料發(fā)電是世界上最通用的方法。然而,利用生物質(zhì)能發(fā)電,并遵守一些規(guī)定和限制會更有效率。眼下主要有四種類型的生物發(fā)電系統(tǒng):直燃,混燒,煤氣化,模塊化系統(tǒng)。大多數(shù)發(fā)電廠使用生物質(zhì)直燃系統(tǒng),用化石燃料來發(fā)電。圖1顯示了如何使用生物質(zhì)燃料在工廠中發(fā)電。生物質(zhì)的燃燒鍋爐產(chǎn)生高壓蒸汽,蒸汽被引入汽輪機,帶動一系列氣動渦輪葉片,

7、使渦輪旋轉(zhuǎn),而渦輪連接到發(fā)電機,因此,流動的蒸汽致使渦輪旋轉(zhuǎn),發(fā)電機旋轉(zhuǎn)和電力的生產(chǎn)。生物質(zhì)能鍋爐產(chǎn)生的電一般在50兆瓦范圍左右,相比燃煤發(fā)電廠中的15兆瓦左右。因此,有人建議,在一些電廠,如在美國亞什蘭的海灣發(fā)電站,在高負荷期使用煤而在低負荷期使用生物質(zhì)發(fā)電,這將節(jié)儉煤的使用。然而,到目前為止,用直接燃燒的木材發(fā)電是最省事的方法。另外,除非它和像煤一樣的其它能源組合使用,否則就可能沒有競爭力。</p><p>

8、<b>  生物質(zhì)能的優(yōu)點:</b></p><p>  使用生物質(zhì)作為替代能源來發(fā)電具有一定的經(jīng)濟效益。再者,它也是一種有效的社區(qū)或工業(yè)區(qū)的資源來源。相比而言,即使發(fā)達國家能夠利用這一資源,以彌補其它像石油,天然氣或煤資源的不足。其中最重要的優(yōu)勢是它的價格低廉;而且是一種現(xiàn)成的能源。此外,它是一種可持續(xù)、可長期使用的資源,它可以在任何時候任何地方很容易地發(fā)現(xiàn)使用。生物質(zhì)發(fā)電廠更大的優(yōu)勢是能

9、幫助許多國家減少失業(yè)。施安那 貝爾德,中型項目的蘇格蘭綠黨的能源發(fā)言人說: “就新的發(fā)電站的建立和它創(chuàng)造的相當數(shù)量的就業(yè)機會而言,這是個好消息” 。如在蘇格蘭鄧弗里斯郡的洛克比建立的生物質(zhì)能源發(fā)電廠,將支持英國經(jīng)濟也將幫助政府降低失業(yè)率。</p><p><b>  生物質(zhì)能的缺點:</b></p><p>  如同任何可再生能源一樣,利用生物質(zhì)發(fā)電存在一定的缺陷。生

10、物質(zhì)確實影響環(huán)境嗎?這個問題已經(jīng)被問了很多次。事實上,因為它在燃燒時會產(chǎn)生碳氣體,因此許多人擔心的是它在全球氣候變暖中的作用。然而,如果你了解生物質(zhì)周期的話,可能知道從這個角度看是錯誤的。雖然生物質(zhì)可在世界任何地方看到,有些地方如在中東的沙漠地區(qū),如沙特阿拉伯,找到足夠的可用作生物質(zhì)的植被是一件很困難的事。因此,把植被運送到該地區(qū),將是昂貴的和毫無用處的。</p><p><b>  結(jié)論:</b

11、></p><p>  總之,這篇文章已經(jīng)表明,使用生物質(zhì)的行業(yè),特別是像發(fā)電廠這樣的工業(yè),將有助于人們找到工作,并有助于各國政府減少失業(yè)率。此外,每年許多國家花費數(shù)十億美元購買石油或天然氣用來發(fā)電,為此,如果用生物質(zhì)作為替代能源來發(fā)電將是更加經(jīng)濟和有效。在電力市場,可以說:能源就是金錢。就生物質(zhì)能源而言,這一說法更為確切。此外,生物質(zhì)可用于不同的地方,這意味著更多的靈活性。雖然使用生物質(zhì)的電廠將產(chǎn)生功耗低

12、于它使用化石燃料時而產(chǎn)生的電能,但在村莊和小城鎮(zhèn),使用生物質(zhì)將比使用常用的化石燃料更為經(jīng)濟。</p><p>  Biomass as an Alternative Fuel for Generating Electricity</p><p>  Written by : Eng. Fahad A. Rafai</p><p>  refaeefa@hotmail

13、.com</p><p><b>  September</b></p><p>  Introduction</p><p>  Electrical energy has many different sources and can be produced in different ways. However, countries are

14、competing to produce energy and trying to have unlimited sources for producing it. Moreover, producing electrical energy using normal fossil fuels, such as, oil, coal and so on has some major problems, from the cost of f

15、uel to the pollution. At the end of the last century, engineers have started looking for new sources which have the same advantages as the fossil fuels while avoiding their </p><p>  "In the United Stat

16、es, since 1973 there has been a dramatic increase in biomass use, especially in thermal and electrical applications of wood residues". This essay will examine the using of biomass energy as an alternative fuel in th

17、e electricity industry. Initially, it will cover a brief background on biomass and include its sources and history. Secondly, the using of biomass for generating electricity in power plants will be investigated. Then, so

18、me of the advantages and disadvantages of usin</p><p>  Biomass in Brief</p><p>  Biomass is one of the oldest sources of energy in the world. Although we have been using it all the time, it may

19、 have been never heard about its scientific name. Biomass known as living material or specifically, it is the conversion of the stored energy in the dead trees, tree branches, wood, crops and even animals into energy so

20、that we can use it. For example, "The major categories of biomass fuels used in the United States today include, wood processing residues, in-forest residues, agricultu</p><p>  As a result, biomass ene

21、rgy can be found easily in any place and any time. In fact, biomass will not be useful for producing electrical power energy unless converted into another form. Consequently , if any company wants to use biomass as a sou

22、rce of energy instead of oil or gas, it will need to collect the biomass ( plants, wood and so on ) and burn it in special places, then the heat of this burning can be used in a steam turbine to generate electricity. In

23、the same way, power plants can use b</p><p>  Although biomass energy has been used many years ago, some countries still use it as a fuel in electrical power generation until now. In contrast, some countries

24、 stopped using it because of its environmental impacts. It has been said that biomass has been contributing to the environmental pollution. However, the benefits of this energy encouraged some societies to use it, for i

25、nstance, "BEG (The Biomass Energy Group) has concluded that a biomass industry in Scotland has the potential to supply </p><p>  Electrical Power Generation from waste</p><p>  Generating e

26、lectricity in power plants using fossil fuel is the most popular method in the world. However, using biomass to generate electricity can be efficient with some regulations and limitation. There are four main types of bio

27、mass power systems: direct-fired, co-fired, gasification, and modular systems. Most of the power plants which use biomass are direct-fired systems which use the same technique of fossil-fuel fired power plants. Figure 1

28、shows how to use biomass as fuel in power plants</p><p>  Figure 1: Using Biomass to produce electricity in power plants.</p><p>  Advantages of using Biomass:</p><p>  Using biomas

29、s as an alternative energy to generate electrical power has some economical benefits. Moreover, it can be a useful source for energy in the small societies or small industrial areas. In contrast, even developed countries

30、 can use this source to compensate for the lack of the other sources, such as, oil, gas or coal. One of the most important advantages of biomass is its cheap prices; also it is a readily available source of energy. In ad

31、dition, it is a continuous and long term source,</p><p>  Disadvantages of using Biomass</p><p>  Like any renewable source, biomass has some disadvantages for using it to generate electrical po

32、wer. Does biomass affect the environment? This question has been asked many times. In fact, many people are concerned about the contribution of biomass in the global warming because the combustion of biomass will produce

33、 carbon into the air. However, this point of view could be wrong if you understand the biomass cycle. Although biomass can be found anywhere in the world, some places like desert areas</p><p>  Figure 2: Car

34、bon cycle.</p><p>  Conclusions:</p><p>  To sum up, this essay has shown that using biomass in industry and specifically in power plants to produce electrical power, would help many people to f

35、ind jobs and could help the governments to diminish the unemployment rates. Moreover, every year, countries spend billions of dollars to sell oil or gas for generating electricity, for this reason, it will be more econom

36、ical and useful if biomass has been used. In the electricity markets it can be said: energy is money. And by using biomass this </p><p>  References :</p><p>  1. Black, Wood-fuelled power stati

37、on to be UK's first, The Scotsman,</p><p>  http://thescotsman.scotsman.com (_ August ____)</p><p>  2. Haq, Z, The Energy Information Administration, Biomass for Electricity</p><

38、p>  Generationhttp://www.eia.doe.gov/oiaf/analysispaper/biomass</p><p>  3. Morris, G. The Value of the Benefits of U.S. Biomass Power, National</p><p>  Renewable Energy Laboratory, Berkeley

39、, California, USA.</p><p>  4. Overend, R.P. Production of Electricity from Biomass Crops – US</p><p>  Perspective. National Renewable Energy Laboratory, Golden, Colorado, USA</p><p&

40、gt;  5. Slesser, M & Lewis, Biomass as a Nonfossil Fuel Source, A Halsted</p><p>  Press Book. </p><p>  6. Promoting and Accelerating the Market Penetration of Biomass</p><p> 

41、 Technology in Scotland, Scottish Executive</p><p>  www.scotland.gov.uk/Resource/Doc/.pdf</p><p>  7. Biomass, Energy matters</p><p>  http://library.thinkquest.org/types/biomass&l

42、t;/p><p>  8. Biomass Energy, Energy Quest</p><p>  http://www.energyquest.ca.gov/story/chapter.html</p><p>  9.Figure1:BBCwebsite </p><p>  http://news.bbc.co.uk/hi/sci/t

溫馨提示

  • 1. 本站所有資源如無特殊說明,都需要本地電腦安裝OFFICE2007和PDF閱讀器。圖紙軟件為CAD,CAXA,PROE,UG,SolidWorks等.壓縮文件請下載最新的WinRAR軟件解壓。
  • 2. 本站的文檔不包含任何第三方提供的附件圖紙等,如果需要附件,請聯(lián)系上傳者。文件的所有權(quán)益歸上傳用戶所有。
  • 3. 本站RAR壓縮包中若帶圖紙,網(wǎng)頁內(nèi)容里面會有圖紙預覽,若沒有圖紙預覽就沒有圖紙。
  • 4. 未經(jīng)權(quán)益所有人同意不得將文件中的內(nèi)容挪作商業(yè)或盈利用途。
  • 5. 眾賞文庫僅提供信息存儲空間,僅對用戶上傳內(nèi)容的表現(xiàn)方式做保護處理,對用戶上傳分享的文檔內(nèi)容本身不做任何修改或編輯,并不能對任何下載內(nèi)容負責。
  • 6. 下載文件中如有侵權(quán)或不適當內(nèi)容,請與我們聯(lián)系,我們立即糾正。
  • 7. 本站不保證下載資源的準確性、安全性和完整性, 同時也不承擔用戶因使用這些下載資源對自己和他人造成任何形式的傷害或損失。

評論

0/150

提交評論