Nuclear Power Plants

There are two main differences between a nuclear power plant and a fossil-fuel power plant: the first one uses nuclear fuel (uranium) instead of fossil fuel and it has a nuclear reactor instead of a boiler. In fact, it can have one or more nuclear reactors.

The fuel is placed in the reactor vessel filled with fluid. The fuel heats the fluid and the super-hot fluid goes to the steam generator.

A steam generator is a heat exchanger used to convert water into steam from heat produced in the nuclear reactor. It can be 70 feet in height and weigh 800 tons. A steam generator includes a series of heat exchangers comprising tubes. The fluid heated in the reactor to the temperature of 250-300°C is delivered into the heat exchanger tubes. It is pumped under high pressure (up to 150 atmospheres), to prevent it from boiling. The fluid is highly radioactive, so it should never come into contact with the water which changes to steam. The water flows over the heat exchanger tubes where it heats and then evaporates.

The steam produced activates the steam turbine, the turbine in its turn drives the generator producing electricity. The nuclear reactor is cooled by water circulating through a system of tubes. A nuclear plant has a steam condenser in which the steam is condensed via cooled water and returned to the steam generator where it is heated once again. This is the most common way to extract usable energy from a controlled nuclear reaction.

Nuclear power plants have their advantages as well as disadvantages. The reactors and steam generators operate in them noiselessly; the atmosphere is not polluted by dust and smoke. As to the fuel consumption, it is of no special importance and there is no problem of fuel transportation.

The disadvantage of power plants utilizing nuclear fuel is their radiation. They are considered problematic for their safety and health risks. Radioactivity produced in the reactors is dangerous for the attending personnel. That is why, the reactors and steam generators are installed underground. They are also shielded by thick (up to 1.5 m) concrete walls. All their controls are operated by means of automatic devices. These measures serve to protect people from radioactive radiation.

· Transcribe the following words, practice reading them, give Russian equivalents:

Nuclear, auxiliary, uranium, fuel, fluid, exchanger, generator, convert, steam, emission, produce, circulate, temperature, include, comprise, turbogenerator, pollute, importance, personnel, install, measure

· Are the following sentences true or false? Correct the false sentences.

1. Nuclear power plants and steam power plants have the same units.

2. Nuclear reactors can’t work without uranium.

3. The super hot fluid comes into contact with the water that is converted into steam.

4. The steam produced in the steam generator can’t be used twice.

5. Nuclear power plants are considered to be safe.

6. The reactor is installed underground because it makes a lot of noise.

· Use the following paragraphs to answer the questions.

Paragraphs 1-4

What units do nuclear power plants have?

Paragraph 3

What is the function of the water that flows over the heat exchanger tubes?

Paragraph 4

What is the function of steam?

Paragraphs 5, 6

Are nuclear power plants dangerous for the environment?

Paragraph 6

What measures serve to protect people from radioactive radiation?

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