Bài mẫu IELTS Writing Task 1: The diagram below shows the production of steam using a gas cooled nuclear reactor.

The diagram shows how steam is produced by using a gas cooled nuclear reactor.

Overall, the system has two main parts, a reactor and a heat exchanger. Gas is heated in the reactor and then it is used to heat water in the heat exchanger to make steam.

The reactor is surrounded by concrete radiation shielding, and inside it there is a pressure vessel. There are charge tubes at the top which are used to load the fuel elements, and boron control rods which go down into the reactor. In the middle of the reactor, there are uranium fuel elements and graphite moderators.

First, cool gas is pushed into the bottom of the reactor by a gas blower. The gas goes up past the uranium fuel elements and it becomes hot. Then the hot gas leaves the top of the reactor and goes through the hot gas duct to the heat exchanger. At the same time, water is pumped into the heat exchanger by a water circulator. The hot gas heats the water in the pipes, and the water becomes steam, which goes to the turbo-alternator. After that, the gas becomes cool again and goes back to the reactor through the cool gas duct.