火电厂专业英语分析解析

1. Modern electric generating stations 1.现代发电厂1.1 how power is generated 1.1 电是如何产生的Virtually all the electric power in the United States today is generated by one of the methods depicted schematically in fig.1.1. 事实上，今天所有的美国电力都是由图1.1所示意的一种方法所产生的。Approximately 90% of the electric power are generated 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%的电力是通过热机发电的理念而产生的。这个观念认为，热能可以转化为机械能，而机械能又可以通过发电机转化为电能，大部分电厂使用朗克循环的方法

将热能转化为电能Fossil-fuel plants represent the most common application of the thermal-mechanical concept. 化石燃料电厂是最典型的热电应用Coal, gas, or a petroleum fraction is mixed with air and injected into a boiler where combustion takes place. 煤、天然气、石油与空气混合注入到锅炉中进行燃烧。In most plants, heat from combustion is used to convert water to steam. 在大部分电厂中，燃烧产生的热量将水转化成水蒸气。This steam, in turn, flows through large pipes to a multistage turbine. 蒸汽流经大型的管道进入多级汽轮机中。

In some plants fired by petroleum or gas, the combustion products flow directly to the turbine. 在一些燃油和燃气火电站中，燃烧产物直接流入汽轮机中As the steam or hot gas passed through the turbine, energy is extracted from the vapor to run the turbine. 当蒸汽或热气流经汽轮机时，蒸汽中的能量也流经汽轮机。The turbine is mechanically connected to the generator, and it drives or rotates the generator, allowing the production of electrical energy. 汽轮机和发电机在结构上相联，它驱动发电机转动，产生电能。1.2 Steam Power Plants 1.2 蒸汽发电厂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. 最广泛应用的矿物质燃烧系统是烧煤或者烧油来提供热能，利用蒸汽轮机来驱动

发电机。Fossil-fuel plants represent the most common application of the thermal-mechanical concept. 矿物质燃料电厂体现的是最普通的热机发电的理念Coal, gas, or a petroleum fraction is mixed with air and injected into a boiler where combustion takes place. 煤、燃气、石油夹杂在空气中注入正在燃烧的锅炉内。In most plants, heat from combustion is used to convert water to steam. 在大部分电厂中，燃烧获得的热量用于将水转化为蒸汽。This steam, in turn, flows through large pipes to a multistage turbine. 蒸汽依次流过大型的管道，进入多级的汽轮机中

In some plants fired by petroleum or gas, the combustion products flow directly to the turbine. 以油气为燃料的电厂其燃烧出的蒸汽直接导向汽轮机As the steam or hot gas passed through the turbine, energy is extracted from the vapor to run the turbine. 当蒸汽和热气经过汽轮机时，由蒸汽中所散发出的热量推动汽轮机，The turbine is mechanically connected to the generator, and it drives or rotates the generator, allowing the production of electrical energy. 汽轮机与发电机由机械连接起来，由它驱动或者转动发电机，实现发电。

Key: HPT=high pressure turbine LPT=low-pressure turbine IPT=intermediate-pressure turbine Figure 1.2 Heat 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. 在将来十年甚至一直往后，煤都是美国发电厂最大的燃料来源As early as 1925, coal generated 57% of this country’s electrical power.

1925年，国家靠煤发电57%，Coal generated an average of 52% of the electrical power during the period from 1925 to 1970. 从1925年到1970年，国家靠煤发电52%，Utilities burn about 65% of all the coal mined in the united states. 使用了占全国煤燃料的65%

In 1984 it is projected that coal will generate approximately 47% of the electrical power, and 875 million tons of coal will be consumed. 在1984年，计算出靠煤发电47 %，消耗了8.75亿吨的煤。U.S. policy is to move away from the use of petroleum for electric power generation. 美国的政策是取缔使用燃油发电This de-emphasis on petroleum use for electric power generation will take years to take a substantial effect. 取缔燃油发电还需要过一些年才能发挥实效Power 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，由于原油禁运燃油发电略有下降，但是在1976年燃油发电量达

到历史最高水平，燃油5.56亿桶，发电3200亿千瓦时It 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. 据估计，七十年代的燃油发电厂的建成，导致燃烧9亿桶燃油发电的使用高峰，这个

数值会在今后下降As coal and nuclear plants assume a greater share of the base-loaded generation, oil plants will be increasingly used for peak or intermediate power production. 随着燃煤和核电电厂占发电比例的增大，燃油电站会越来越多地用于发电的中介部

分

However, it is expected that utilities will continue to use substantial amounts of petroleum well into the next century. 但是，有人预测，在下一个世纪，燃油还会被使用相当的一部分。Introduction to Power Plant Systems and Components 火电厂系统和部件的介绍

The block diagram of Fig.1.3 show the major segments of a modern coal-fired power plant. 图1.3所示的方格的内容就是现代火电厂的主机设备的构成。

After crushing and pulverizing, the coal is fed to the furnace, where it is burned. 煤经过粉碎和研磨之后，被送到炉腔中进行燃烧。In the flame region, much of the heat generated is transferred to boiler tubes which line the walls. 在火焰区，大部分所产生的热量被转移到沿墙壁布置的锅炉管道上。The steam water mixture formed in the boiler tubes proceeds to a steam drum, where the vapor and liquid are separated. 在锅炉管道里的汽水混合物流入到汽包里，在这里进行水汽分离。

The liquid is returned to the boiler tubes and the vapor proceeds to a superheater. 液体流回锅炉管道，而水蒸气则流入过热器。

There the hot gases leaving the flame region superheat the saturated steam produced in the boiler section. 热气从火焰区出来，对锅炉管道里产生的水蒸气进行过热。The superheated steam produced in the boiler section. The superheated steam proceeds to the turbine, where its thermal energy is converted to mechanical energy. 过热后的水蒸气流过锅炉，又流过汽轮机，在这里热能被转化为机械能。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. 蒸汽在离开汽轮机的高压级后，在进入汽轮机低压级之前，在炉腔中被重新加热。The steam exiting from the low-pressure turbine proceeds to a condenser. 蒸汽离开汽轮机低压级后，进入一个冷凝器中。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. 从冷凝器中流出的液体在流回炉之前，利用从汽轮机中流出的蒸汽，在供水加热器

中再次加热，凝汽器的凝结水在返回炉腔之前，在再生式给水加热器中利用汽轮机

的抽气进行再热。The feed-water then proceeds to the furnace, where it is brought to near saturation in the economizer.