LIGHT WATER NUCLEAR POWER PLANT

LIGHT WATER NUCLEAR POWER PLANT
Definition
Light-water nuclear – power plant is a nuclear reactor in which U235 fuel rods are submerged in water. Here, water acts as coolant and moderator.
The fission reaction is controlled by inserting or removing the control rods of B10 automatically from the spaces in between the fuel rods. The heat emitted by fission of U-235 in the fuel core is absorbed by the coolant (light water). The heated coolant (water at 300°C) then goes to the heat exchanger containing sea water. The coolant here, transfers heat to sea water, which is converted into steam. The steam then drives the turbines, generating electricity.

Pollution
Though nuclear power plants are very important for production of electricity, they will cause a serious danger to environments.

Problem on disposal of reactor waste
Disposal of reactor waste is another important problem because the fission products viz., Ba139 & Kr92 are themselves radioactive. They emit dangerous radiation for several hundred years. So the waste is packed in concrete barrels, which are buried deep in the sea.