DISPOSAL OF RADIOACTIVE WASTES :

Since Nuclear wastes are extremely dangerous the way in which they are disposed is strictly controlled by international agreement.

Classification Of Radio Active Wastes :

The Nuclear Wastes are usually classified into three categories.

1. High level Wastes (HLW)

2. Medium Level wastes (MLW)

3. Low level Wastes ( LLW)

I) HIGH LEVEL WASTE (HLW) :

Examples : Spent Nuclear Fuel.

HLW have a very high radioactivity per unit volume. They have to be cooled and stored for several decades by its producer before disposal. Since they are too dangerous, must be contained either by converting them into inert solids (ceramics) and then buried deep into earth or stored in deep salt mines.

II) MEDIUM LEVEL WASTE (MLW) :

Examples : Filters, reactor components, etc.,

MLW are solidified and are mixed with concrete in steel drums before being buried in deep mines or below the sea bed in concrete chambers.

III) LOW LEVEL WASTES (LLW) :

Examples : Solids or liquids contaminated with traces of radioactivity.

LLW are disposed off in steel drums in concrete - lined.

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Mechinopedia For Mechanical Engineers

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