火電廠專業(yè)英語(yǔ)

1、1. Modern electric generating stations1.現(xiàn)代發(fā)電廠1.1 how power is generated 1.1 電是如何產(chǎn)生的 Virtually all the electric power in the United States today is generated by one of the methods depicted schematically in fig.1.1. 事實(shí)上，今天所有的美國(guó)電力都是由圖1.1所示意的一種方法所產(chǎn)生的。Approximately 90% of the electric power are generated

2、 by what is called the thermal-mechanical generation concept. In this concept, heat energy is converted into mechanical energy which powers an electric generator. Most of these power plants use the Rankine cycle for conversion of heat energy to mechanical power. 接近90%的電力是通過(guò)熱機(jī)發(fā)電的理念而產(chǎn)生的。這個(gè)觀念認(rèn)為，熱能可以轉(zhuǎn)化為

3、機(jī)械能，而機(jī)械能又可以通過(guò)發(fā)電機(jī)轉(zhuǎn)化為電能，大部分電廠使用朗克循環(huán)的方法將熱能轉(zhuǎn)化為電能Fossil-fuel plants represent the most common application of the thermal-mechanical concept. 化石燃料電廠是最典型的熱電應(yīng)用Coal, gas, or a petroleum fraction is mixed with air and injected into a boiler where combustion takes place.煤、天然氣、石油與空氣混合注入到鍋爐中進(jìn)行燃燒。In most plants,

4、heat from combustion is used to convert water to steam. 在大部分電廠中，燃燒產(chǎn)生的熱量將水轉(zhuǎn)化成水蒸氣。This steam, in turn, flows through large pipes to a multistage turbine.蒸汽流經(jīng)大型的管道進(jìn)入多級(jí)汽輪機(jī)中。In some plants fired by petroleum or gas, the combustion products flow directly to the turbine. 在一些燃油和燃?xì)饣痣娬局校紵a(chǎn)物直接流入汽輪機(jī)中As the ste

5、am or hot gas passed through the turbine, energy is extracted from the vapor to run the turbine.當(dāng)蒸汽或熱氣流經(jīng)汽輪機(jī)時(shí)，蒸汽中的能量也流經(jīng)汽輪機(jī)。The turbine is mechanically connected to the generator, and it drives or rotates the generator, allowing the production of electrical energy. 汽輪機(jī)和發(fā)電機(jī)在結(jié)構(gòu)上相聯(lián)，它驅(qū)動(dòng)發(fā)電機(jī)轉(zhuǎn)動(dòng)，產(chǎn)生電能。1.2 Stea

6、m Power Plants1.2 蒸汽發(fā)電廠 The most widely used fossil systems burn coal or a heavy petroleum fraction to supply the thermal energy, and employ a steam turbine to power the electric generator.最廣泛應(yīng)用的礦物質(zhì)燃燒系統(tǒng)是燒煤或者燒油來(lái)提供熱能，利用蒸汽輪機(jī)來(lái)驅(qū)動(dòng)發(fā)電機(jī)。Fossil-fuel plants represent the most common application of the thermal-

7、mechanical concept. 礦物質(zhì)燃料電廠體現(xiàn)的是最普通的熱機(jī)發(fā)電的理念Coal, gas, or a petroleum fraction is mixed with air and injected into a boiler where combustion takes place. 煤、燃?xì)?、石油夾雜在空氣中注入正在燃燒的鍋爐內(nèi)。 In most plants, heat from combustion is used to convert water to steam. 在大部分電廠中，燃燒獲得的熱量用于將水轉(zhuǎn)化為蒸汽。This steam, in turn, flows

8、 through large pipes to a multistage turbine.蒸汽依次流過(guò)大型的管道，進(jìn)入多級(jí)的汽輪機(jī)中 In some plants fired by petroleum or gas, the combustion products flow directly to the turbine. 以油氣為燃料的電廠其燃燒出的蒸汽直接導(dǎo)向汽輪機(jī)As the steam or hot gas passed through the turbine, energy is extracted from the vapor to run the turbine.當(dāng)蒸汽和熱氣經(jīng)過(guò)

9、汽輪機(jī)時(shí)，由蒸汽中所散發(fā)出的熱量推動(dòng)汽輪機(jī)， The turbine is mechanically connected to the generator, and it drives or rotates the generator, allowing the production of electrical energy. 汽輪機(jī)與發(fā)電機(jī)由機(jī)械連接起來(lái)，由它驅(qū)動(dòng)或者轉(zhuǎn)動(dòng)發(fā)電機(jī)，實(shí)現(xiàn)發(fā)電。Key:HPT=high pressure turbine LPT=low-pressure turbine IPT=intermediate-pressure turbineFigure 1.2 Heat

10、 cycle for a coal-fired boiler Coal has been, and for at the next decade or so will continue to be, the largest source of fuel for electrical generating stations in the United States. 在將來(lái)十年甚至一直往后，煤都是美國(guó)發(fā)電廠最大的燃料來(lái)源As early as 1925, coal generated 57% of this countrys electrical power. 1925年，國(guó)家靠煤發(fā)電57%，

11、Coal generated an average of 52% of the electrical power during the period from 1925 to 1970. 從1925年到1970年，國(guó)家靠煤發(fā)電52%，Utilities burn about 65% of all the coal mined in the united states. 使用了占全國(guó)煤燃料的65%In 1984 it is projected that coal will generate approximately 47% of the electrical power, and 875 mi

12、llion tons of coal will be consumed.在1984年，計(jì)算出靠煤發(fā)電47 %，消耗了8.75億噸的煤。 U.S. policy is to move away from the use of petroleum for electric power generation.美國(guó)的政策是取締使用燃油發(fā)電 This de-emphasis on petroleum use for electric power generation will take years to take a substantial effect.取締燃油發(fā)電還需要過(guò)一些年才能發(fā)揮實(shí)效 Powe

13、r generation by petroleum dropped slightly in 1947-1975 as a result of the original oil embargo, but in 1976 the use of petroleum rose to an all-time high of 556 million barrels for the generation of 320 billion kilowatt-hours. 在1947年到1975年，由于原油禁運(yùn)燃油發(fā)電略有下降，但是在1976年燃油發(fā)電量達(dá)到歷史最高水平，燃油5.56億桶，發(fā)電3200億千瓦時(shí)It

14、has been estimated that completion of all the petroleum-fired generating units on order during the 1970s will result in a peak use of 900 million barrels of petroleum for power generation should begin to decline thereafter.據(jù)估計(jì)，七十年代的燃油發(fā)電廠的建成，導(dǎo)致燃燒9億桶燃油發(fā)電的使用高峰，這個(gè)數(shù)值會(huì)在今后下降 As coal and nuclear plants assu

15、me a greater share of the base-loaded generation, oil plants will be increasingly used for peak or intermediate power production. 隨著燃煤和核電電廠占發(fā)電比例的增大，燃油電站會(huì)越來(lái)越多地用于發(fā)電的中介部分However, it is expected that utilities will continue to use substantial amounts of petroleum well into the next century.但是，有人預(yù)測(cè)，在下一個(gè)世

16、紀(jì)，燃油還會(huì)被使用相當(dāng)?shù)囊徊糠?。Introduction to Power Plant Systems and Components 火電廠系統(tǒng)和部件的介紹The block diagram of Fig.1.3 show the major segments of a modern coal-fired power plant.圖1.3所示的方格的內(nèi)容就是現(xiàn)代火電廠的主機(jī)設(shè)備的構(gòu)成。 After crushing and pulverizing, the coal is fed to the furnace, where it is burned. 煤經(jīng)過(guò)粉碎和研磨之后， 被送到爐腔中進(jìn)行燃

17、燒。In the flame region, much of the heat generated is transferred to boiler tubes which line the walls. 在火焰區(qū)，大部分所產(chǎn)生的熱量被轉(zhuǎn)移到沿墻壁布置的鍋爐管道上。The steam water mixture formed in the boiler tubes proceeds to a steam drum, where the vapor and liquid are separated. 在鍋爐管道里的汽水混合物流入到汽包里，在這里進(jìn)行水汽分離。The liquid is retur

18、ned to the boiler tubes and the vapor proceeds to a superheater. 液體流回鍋爐管道，而水蒸氣則流入過(guò)熱器。There the hot gases leaving the flame region superheat the saturated steam produced in the boiler section. 熱氣從火焰區(qū)出來(lái)，對(duì)鍋爐管道里產(chǎn)生的水蒸氣進(jìn)行過(guò)熱。The superheated steam produced in the boiler section. The superheated steam procee

19、ds to the turbine, where its thermal energy is converted to mechanical energy. 過(guò)熱后的水蒸氣流過(guò)鍋爐，又流過(guò)汽輪機(jī)，在這里熱能被轉(zhuǎn)化為機(jī)械能。 The steam leaving the high-pressure stage of the turbine is reheated in the furnace prior to being sent to the low-pressure sections of the turbine. 蒸汽在離開汽輪機(jī)的高壓級(jí)后，在進(jìn)入汽輪機(jī)低壓級(jí)之前，在爐腔中被重新加熱。The

20、 steam exiting from the low-pressure turbine proceeds to a condenser. 蒸汽離開汽輪機(jī)低壓級(jí)后，進(jìn)入一個(gè)冷凝器中。The liquid from the condenser is reheated in regenerative feed-water heaters, using steam bled from the turbine, prior to being returned to the furnace. 從冷凝器中流出的液體在流回爐之前，利用從汽輪機(jī)中流出的蒸汽，在供水加熱器中再次加熱，凝汽器的凝結(jié)水在返回爐腔之前

21、，在再生式給水加熱器中利用汽輪機(jī)的抽氣進(jìn)行再熱。The feed-water then proceeds to the furnace, where it is brought to near saturation in the economizer. 給水流入到爐腔中，它可以在省煤器中達(dá)到接近飽和The gases leaving the economizer preheat the entering air and are then discharged through the stack.氣體流過(guò)省煤器，使空氣提前預(yù)熱，然后釋放出來(lái) Particulates in the gas str

22、eam are removed by electrostatic precipitators prior to discharge. In newer plants, the exit gases are also scrubbed to remove SO2.蒸汽中的微粒在被蒸汽被釋放出之前，靜電除塵器除去。在新電廠中，所釋放的氣體還要考慮脫硫。The major factor in establishing the size of the power plant components is the required net power output.所建電廠的規(guī)模由凈發(fā)電量所決定。 How

23、ever, the design is significantly affected by the characteristics of the coal being burned, coal delivery methods, combustion technique selected, and constituents of the coal ash.但是，對(duì)電廠的設(shè)計(jì)要考慮到所燃燒煤的特性，煤的運(yùn)輸方法，所選擇的燃燒技術(shù)，以及煤灰的處理方法。 The most significant coal characteristics are:煤的重要特性是：Moisture content 水份

24、High heating value 熱溫度Grindability index 可磨系數(shù)Ash content 灰特性Ash fusion temperature 灰熔點(diǎn)的溫度Sulfur content 硫份These specific coal characteristics are far more meaningful in the design of the equipment and the station than is the rank of the coal being burned.煤的特性在對(duì)設(shè)備的設(shè)計(jì)和電廠的設(shè)計(jì)方面比煤的等級(jí)更加重要 Each specific co

25、al characteristic can affect the design of certain plant equipment and components. 煤的每種特性都會(huì)對(duì)專門的設(shè)備和部件都有影響As an example, consider the effect of the moisture on power plant components. 比如，煤的水分對(duì)電廠部件的影響 The general effect is to increase most boiler components sizes and to reduce boiler efficiency.總的影響是會(huì)增

26、加鍋爐部件的尺寸，而減小鍋爐的效率A high moisture content will require a larger air heater. 水分越高，越需要更大的空氣加熱器。This, in turn, requires an increase in the temperature of the inlet air to the pulverizers（粉碎機(jī)） since a greater volume of air is required to dry the coal in the pulverizer. 受此影響，需要增加進(jìn)入粉碎機(jī)的空氣的溫度，因?yàn)樾枰篌w積的空氣來(lái)干燥

27、在粉碎機(jī)中的煤。This increases the initial primary air fan size and reduces the forced draft fan sizes. 這會(huì)增加一次風(fēng)機(jī)的尺寸而減小從動(dòng)風(fēng)扇的尺寸。The burning of coal with a high moisture content results in a higher flue gas dew point, and raises the stack temperature needed to prevent corrosion. 燃煤含有高水分，會(huì)導(dǎo)致高流量的氣霧，而且會(huì)提高防腐蝕的溫度。T

28、he net result of a high-moisture-content coal is to reduce the overall power plant efficiency.高水分煤會(huì)減少整個(gè)電廠的效率，The high heating value of the coal is another property that significantly affects plant design. 煤的高位發(fā)熱值是影響電站設(shè)計(jì)的另外一個(gè)重要的特性The high heating value(HHV) establishes the rate at which coal is fed i

29、nto the furnace(firing rate). 高位發(fā)熱值確定煤被送入爐腔的頻率Since the HHV can vary from 19,000 kJ/kg to well over 28,500kJ/kg(12000 Btu/lb) and since the firing rate for a given furnace or boiler out put is inversely proportional to the HHV, it is easy to see that mass firing rates can vary by over 50%. 由于HHV的值會(huì)從

30、19000 kJ/kg變化到28,500kJ/kg，而且由于爐腔忽而鍋爐的燃燒頻率與HHV成反比，所以，燃燒頻率很容易改變50%。Thus the HHV will affect the design of the boiler combustion zone, burners, pulverizers, coal feeders, silo storage requirements, coal-handling equipment, and the size of the active and inactive coal storage.因此，HHV會(huì)影響到鍋爐的燃燒區(qū)域，燃燒器，磨煤機(jī)、送

31、煤機(jī)、筒倉(cāng)儲(chǔ)備需求、輸煤設(shè)備的設(shè)計(jì)，以及煤儲(chǔ)存的動(dòng)態(tài)與靜態(tài)。Air fan 風(fēng)機(jī)Air heater 空氣預(yù)熱器Ash fusion temperature 灰熔點(diǎn)溫度Ash hopper 灰斗 Boiler 鍋爐Burner 燃燒器Coal ash 煤灰Coal feeder 給煤機(jī)Coal plant 燃煤電廠Coal-fired power plant 燃煤電廠Coal-handing equipment 輸煤設(shè)備Condensate pump 凝結(jié)水泵Combustion 燃燒Combustion technique 燃燒技術(shù)Condensate 燃燒區(qū)Condenser 凝汽器Con

32、tent 成分Convert 轉(zhuǎn)換Cooling tower 冷卻水塔Crush 破碎Cycle 循環(huán)Deaerate 除去空氣Dew 露Dew point 露點(diǎn)Draft 通風(fēng)Drum 鍋筒，汽包Economizer 省煤器Efficiency 效率Electric generator 發(fā)電機(jī)Electrostatic 靜電的Electrostatic precipitator 靜電除塵器Embargo 禁止進(jìn)出口，禁運(yùn)Fan 風(fēng)機(jī)Feed pump 給水泵Feed-water 給水Firing rate 燃燒率Flame 火焰Flue 煙道Flue gas 煙道氣Forced-draft

33、fan 送風(fēng)機(jī)Fossil 化石的Fossil-fuel 礦物燃料Furnace 爐腔Fusion 熔化Generator 發(fā)電機(jī)Grindability 可磨性Grindability index 可磨系數(shù)Heater 加熱器HHV(High heating value ) 高位發(fā)熱氣Hopper 漏斗Index 系數(shù)Kilowatt 千瓦Kilowatt-hour 千瓦時(shí)Mechanical energy 機(jī)械能Mixture 混合物Moisture 濕度Moisture content 水分Multistage 多級(jí)的Nuclear 原子核Nuclear plant 核電站Precipi

34、tator 除塵器Preheat 預(yù)熱Pressure 壓力Primary air fan 一次風(fēng)機(jī)Property 性能Pulverize 磨碎Pulverizer 磨煤機(jī)Pump 泵Rankine cycle 朗肯循環(huán)Raw 自然的Raw water 原水Reactor 反應(yīng)堆Regenerative 回?zé)崾?，再生式Regenerative feed-water heater 回?zé)崾浇o水加熱器Reheat 再熱Reheater 再熱器Reservoir 儲(chǔ)水池Reservoir water 庫(kù)容水Saturate 使飽和Saturate steam 飽和蒸汽Saturation 飽和狀態(tài)S

35、crub 清洗Separate 分離Silo 儲(chǔ)倉(cāng)Slag 煤渣Stack 煙囪Steam 水蒸氣Steam drum 汽包Steam generator 蒸汽發(fā)生器Steam turbine 汽輪機(jī)Steam-water mixture 汽水混合物Sulfur 硫磺Sulfur content 硫分Superheat 過(guò)熱Superheated steam 過(guò)熱蒸汽Superheater 過(guò)熱器Tower 塔Turbine 葉輪機(jī)Vapor 氣Virtually 幾乎2.Fuel handling and preparation for burning 2.煤的輸送和預(yù)燃燒2.1 Coal

36、Handing Systems2.1 輸煤系統(tǒng)The coal-handing systems at a large modern power plant unload the coal, handle it in the yard, and prepare the coal for burning in the furnace. 大型電廠中的輸煤系統(tǒng)卸煤，輸煤到煤場(chǎng)，然后準(zhǔn)備送入爐腔中進(jìn)行燃燒。Figure 2.1 is a block diagram which shows the major steps in the coal handling operation at a power

37、plant.圖2.1所示意的是在發(fā)電廠中輸煤操作的主要步驟。Since most coal plants burn pulverized coal, this section focuses on the preparation of pulverized coal. 由于大部分電廠燃燒的是煤粉，這部分將集中用于煤粉的準(zhǔn)備。Rail shipment of coal accounts for nearly three-fourths of the coal delivered to U.S. power plants.鐵路運(yùn)輸占到了全美電廠輸煤總量的四分之三。 Shipments of 10,

38、000 tons or more are quickly unloaded by rapid-discharge bottom railroad cars. A 100-ton load of coal can be discharged from a hopper car in 20 seconds. 運(yùn)量為1萬(wàn)噸以上的煤能夠被迅速卸下，100噸的煤能夠在20秒內(nèi)被卸下。 Some western surface-mined coal and some eastern coal from Pennsylvania, West Virginia, and Ohio is shipped by

39、barge.西部產(chǎn)的煤和東部的賓夕法尼亞，西弗吉尼亞，和俄亥俄所產(chǎn)的煤通過(guò)貨輪運(yùn)輸。 Barge shipment of coal accounts for approximately 10% of the coat used by U.S utilities. 輪運(yùn)費(fèi)用接近占美國(guó)用電費(fèi)用的10%The barges used to ship coal are generally not self-unloading, except for a few barges on the Great Lakes. 用來(lái)運(yùn)煤的貨輪逐漸不能夠自我卸煤，除了在五大湖上的少數(shù)運(yùn)煤船。The power pla

40、nt must therefore have its own equipment for unloading barge coal. 電廠就應(yīng)當(dāng)擁有自己的卸煤裝置A typical unloader consists of a tower housing a trolly boom with a clamshell bucket. 一個(gè)標(biāo)準(zhǔn)的卸船機(jī)包括裝有活動(dòng)小車和大抓斗的高塔。The bucket swings over the barge to load and dumps the coal in hoppers on shore. 抓斗在貨輪上來(lái)回走動(dòng)，抓取煤料，在岸上卸下 The re

41、mainder of the coal used by utilities is shipped by either truck or overland conveyer. 剩下的煤由卡車或者陸上傳輸工具進(jìn)行運(yùn)輸Overland conveyers are used where power plants are located near large mines. 當(dāng)電廠和大型煤礦位置較近時(shí)，采用陸地傳輸工具。 Coal stored at a power plant may be placed in either active storage or reserve storage. 電廠的儲(chǔ)備

42、煤可以放在活動(dòng)的煤倉(cāng)或者是固定的煤倉(cāng)The active storage supplies the normal power operation while the reserve storage pile is kept for emergencies and delays in regular shipment.活動(dòng)煤儲(chǔ)備用于提供正常情況下的發(fā)電，而固定煤儲(chǔ)備主要應(yīng)對(duì)一般的輸煤過(guò)程中的緊急事件和延遲現(xiàn)象。 Current utility practice is to keep large inactive reserves, up to 500,000 tons, to ensure a

43、reliable fuel supply for 60 to 90 days of plant operation.現(xiàn)在的固定儲(chǔ)煤可以存儲(chǔ)50萬(wàn)噸煤，保證電廠能夠供應(yīng)60到90天的電。 Since reserve storage piles are usually outdoors, frozen coal is a problem often faced by power plants in the north during the winter months. 由于固定儲(chǔ)煤是在室外堆放，因此對(duì)北方來(lái)說(shuō)，冬天的凍煤現(xiàn)象是一個(gè)要處理的問(wèn)題。Surface moisture on the coa

44、l causes the coal particles to freeze together. 煤表面的水氣導(dǎo)致煤粉凍結(jié)The difficulties caused depend on the coal particle size. 由煤粒的大小決定問(wèn)題的難度。Large chunks of coal have weaker ice bonds than small fine particles because the surface-to-volume ratio is much lower.大塊的煤比小塊煤粉更容易凍結(jié)，因?yàn)榻佑|表面的比率更小。 Severe winter weather

45、 conditions can cause entire train loads or reserve stacks of coal to freeze together solid. 有幾種天氣因素會(huì)導(dǎo)致由鐵路運(yùn)輸和固定儲(chǔ)備的煤會(huì)凍結(jié)成塊There are three methods of dealing with frozen coal: heat, mechanical devices, and freeze-control agents(FCAs). The heating operation is performed in an enclosed thawing shed that

46、is heated by steam, electric, or gas heaters. 有三種方法處理凍煤的問(wèn)題：熱，機(jī)械裝置，解凍機(jī)構(gòu)。加熱操作是在一個(gè)封閉的融化棚中進(jìn)行，該棚由水蒸汽，電和氣進(jìn)行加熱。This method is becoming increasing expensive. 這種方法的成本絕來(lái)越高Alternatively, mechanical devices can be used to shake, crush, or vibrate in order to break up the coal-ice mass.兩者相比，機(jī)械裝置可以搖、壓、震碎煤冰塊。 Free

47、ze-control agents act as antifreeze to weaken the crystalline structure of the ice bond. 解凍裝置能夠弱化冰的晶狀結(jié)構(gòu)，The most widely use FCA is ethylene glycol.最常用的解凍裝置試劑就是乙烯基乙二醇。 It is applied at a few pints per to of coal when the coal is loaded into the car or silo. 當(dāng)煤被運(yùn)到車或倉(cāng)庫(kù)時(shí)，它提供少量的品脫到煤中。 Ethylene glycol has

48、 proved highly successful as freeze-control agent. 乙烯乙二醇作為解凍劑獲得很高的成功率。Coal in active storage is generally kept under cover to protect it from moisture and freezing. 而處于傳動(dòng)狀態(tài)的煤料則被覆蓋起來(lái)防止水分和冰凍，Large concrete bunkers immediately adjacent to the boiler plant are usually used. In some cases, both the activ

49、e and inactive storage is under cover. 在鍋爐室的旁邊會(huì)有大的煤倉(cāng)。在一些情況下，運(yùn)動(dòng)狀態(tài)的煤和靜止儲(chǔ)藏的煤都是被覆蓋的。This is particularly true for western coal, much of which is subbituminous, as it tends to produce large quantities of small particles, known as fines. 對(duì)于西部的煤更是如此，由于大部分西部煤是亞煙煤，所以它可能產(chǎn)出大量的小顆粒狀物。With these coals, dust and m

50、oisture can become serious problems, making closed storage attractive. 使用這些煤，粉塵和水分將是嚴(yán)重的問(wèn)題，使得封閉儲(chǔ)藏非常必要。Large concrete silos are often used for this purpose. The silos are normally kept under a slight negative pressure to minimize dust problems. 建造大煤倉(cāng)就是出于這個(gè)目的。煤倉(cāng)經(jīng)常處于微量的負(fù)壓狀態(tài)。就是為了使得粉塵問(wèn)題最小化。Handing Equipme

51、nt 輸送設(shè)備Very large quantities of coal are handled daily at modern stations.在現(xiàn)代電廠中每天都有大量的煤需要輸送 A 600-Mwe unit, at full power operation, handles and burns approximately 300 tons of coal per hour, or 7200 ton of coal per day. 一個(gè)600MW的機(jī)組，在全額工作狀態(tài)下， 要每小時(shí)輸送和燃燒300噸煤，或者是每天7200噸。Some of the coal delivery and r

52、eceiving systems must be designed to handle up to 4000 tons of coal per hour . 一些煤料輸送和接收系統(tǒng)，必須要設(shè)計(jì)成能夠輸送4000噸煤每小時(shí)。One of the major tasks is building the active and reserve “ stacks ” of coal. 一個(gè)重要的任務(wù)就是要建活動(dòng)式和固定式的煤堆。Although there are a number of techniques and a wide variety of equipment that can be use

53、d to stack and reclaim coal, stacking conveyers are widely used. 盡管有大量的技術(shù)和各種設(shè)備用于堆取煤料，但是堆取料機(jī)很是應(yīng)用很廣泛。A particularly useful device is the bucket wheel stacker/reclaimer, which is designed to perform both the stacking and reclaiming operation.一個(gè)非常有用的裝置就是滾輪式堆取料機(jī)，它被設(shè)計(jì)用來(lái)即可以堆料，又可以取料。 Such a device would typ

54、ically be used to build long triangular piles by taking coal from a conveyer running parallel to the pile. 這種裝置被經(jīng)常用于從輸煤機(jī)上卸煤，堆出長(zhǎng)三角形的煤堆，這要求輸煤機(jī)的走向與煤堆平行。When the pile of coal reaches a maximum height, the stacker moves a few feet and continues to build another pile. 當(dāng)煤堆達(dá)到最大高度時(shí)，取料機(jī)移動(dòng)一小段距離，繼續(xù)堆棧另一堆煤。Reclaiming is done by reversing the direction of the wheel and conveyer. 取煤通過(guò)改變車輪和傳送機(jī)的方向來(lái)實(shí)現(xiàn)。 Other types of in-plant handling systems are lowering wells,