Question:What are the three types of nuclear waste?
Nuclear Waste is classified into High-level, Intermediate-level and Low-level waste.
Low-level waste - LLW:
Low-level nuclear waste contains only small amounts of radioactive material and those materials usually do not remain radioactive for very long.
Low-level waste includes items that have become contaminated with radioactive material or have become radioactive through exposure to neutron radiation.
This waste typically consists of contaminated protective shoe covers and clothing, wiping rags, mops, filters, reactor water treatment residues, equipment and tools, luminous dials, medical tubes, swabs, injection needles, syringes, and laboratory animal carcasses and tissues.
The radioactivity can range from just above background levels found in nature to very highly radioactive in certain cases such as parts from inside the reactor vessel in a nuclear power plant. Low-level waste is typically stored on-site by licensees, either until it has decayed away and can be disposed of as ordinary trash. LLW is often disposed of at sea.
Intermediate-level waste - ILW
This type of waste emits levels of radiation that can be a significant health hazard. These can be contained safely through the use of thick shielding to block the radiation or, for other types, by keeping it in sealed containers to prevent inhalation or ingestion.
Intermediate-level waste, or ILW, can be stored at room temperature without the need for cooling.
Intermediate-level waste typically consists of equipment in reactors, and equipment used to handle spent fuel, fuel element cladding and even the metal work and walls of the reactors outer shells.
It may be solidified in concrete or bitumen for disposal. The concrete is encased in metal drums and then stored in different locations depending on how long the sample will remains dangerously reactive. is used in Europe and elsewhere.
High-level waste - HLW.
High-level waste is the highly radioactive materials produced as a byproduct of the reactions that occur inside nuclear reactors.
High-level wastes take one of two forms:
1.Spent (used) reactor fuel when it is accepted for disposal
2.Waste materials remaining after spent fuel is reprocessed
Spent nuclear fuel is used fuel from a reactor that is no longer efficient in creating electricity, because its fission process has slowed.
However, it is still thermally hot, highly radioactive, and potentially harmful. Until a permanent disposal repository for spent nuclear fuel is built, licensees must safely store this fuel at their reactors.
Reprocessing extracts isotopes from spent fuel that can be used again as reactor fuel. Commercial reprocessing is not done at many sites in the world
Because of their highly radioactive fission products, high-level waste and spent fuel must be handled and stored with care. Since the only way radioactive waste finally becomes harmless is through decay, which for high-level wastes can take hundreds of thousands of years, the wastes must be stored and finally disposed of in a way that provides adequate protection of the public for a very long time.
HLW accounts for 95% of all nuclear waste produced each year.
The amount of HLW worldwide is currently increasing by about 12,000,000 kg, which is the equivalent to about 100 double-decker buses. A 1 Megawatt nuclear power plant produces 30,000 kg of spent nuclear fuel every year.