3. What is radioactivity?
The emission of ionizing radiation or particles caused by the
spontaneous disintegration of atomic nuclei.
Marie Curie first discovered the radioactivity.
4. What is radioactive waste
Radioactive waste is a waste that containing chemical elements
Usually byproducts from
*Mining
*Industries
*Nuclear power industries
*Defense
*Medicine
*Scientific research
5. Radioactive Waste
What Happens?
.Spontaneous decomposition or decay of unstable nuclei to a stable
configuration.
HOW ?
.By emitting certain particles or certain forms of electromagnetic energy.
HOW LONG ?
.Until a stable nuclide has been formed.
7. SOURCES
.Nuclear fuel cycle
.Nuclear weapons decommissioning
.Legacy waste
.Medical
.Industrial
.Naturally occurring radioactive waste(NORM)
.Coal, oil and gas
8. Nuclear fuel cycle
.It often contains radium and its decay products.
.Uranium is used to make fuel from the reprocessing of used fuel.
.The fission product removed from the fuel are a concentrated form of
high level waste are the chemicals used in the process.
.In the United States this used fuel is stored while in other countries such
as Russia the United kingdom France, Japan and India the fuel is
reprocessed to remove the fission products and the fuel can then be re_
used.
9. Nuclear Waste
Decommissioning
.Waste from nuclear weapons decommissioning is unlikely to contain
much beta and gamma activity other than tritium and americium.
.It is more likely to contain alpha emitting actinides such as Pu_239
which is a fissile material used in bombs, plus some material with much
higher specific activities , such as Pu_238 or Po.
10. Legacy Waste
.Due to historic activities typically related to radium industry, uranium
mining, and military programs, there are numerous sites that contain or
are contaminated with radioactivity.
.In the United States alone, the Department of Energy states there are
millions of gallons of radioactive waste as well as thousands of tons of
spent nuclear fuel and material and also huge quantities of
contaminated soil and water.
11. Medical Waste
.Radioactive medical waste tends to contain beta particle and gamma ray
emitters.
.Y_90, used for treating lymphoma(2.7 days)
.1_131, used for thyroid function tests and for treating thyroid cancer(8
days)
.Sr_89,Used for treating bone cancer, intravenous injection(52 days)
12. Industrial Waste
.Industrial source waste can contain alpha, beta, neutron or gamma
emitters.
.Gamma emitters are used in radiography while neutron emitting
sources are used in a range of applications, such as oil well logging.
13. Coal, Oil and Gas
.Coal contain a small amount of radioactive uranium, barium, thorium
and potassium, but in the case of pure coal this is significantly less than
the average concentration of those elements in the earths crust.
.Residues from the oil and gas industry often contain radium and its
decay products.
16. Low Level waste
.Low level waste is generated from hospitals and industry as well as
nuclear fuel cycle.
.consists mainly on demolished material (such as plaster, bricks, metal,
valves, etc.)
.Not harmful to humans and environment.
.Low level waste is suitable for shallow land burial.
17. Intermediate level waste
.contains higher amount of radioactivity and in general require shielding,
but not cooling
.Includes resins, chemical sludge and metal nuclear fuel cladding as well
as contaminated materials from reactor decommissioning.
.It may be solidified in concrete or bitumen for disposal.
18. High level waste
.High level waste is produced by nuclear reactors.
.Arises from burning of uranium fuel in a nuclear reactor
.Produced during reprocessing of used fuel.
20. DISPOSAL AND
MANAGEMENT
Waste disposal is discarding waste with no intention of retrieval.
Waste management means the entire sequence of operations starting
with generation of waste and ending with disposal
21.
22.
23.
24.
25. Sub ductive waste disposal
method
Subduction is process where one tectonic plate slides beneath another
and is eventually reabsorbed into mantle.
It forms high level radioactive waste in a sub ducting plate where it will
be dispersed through mantle.
26. PREVENTION
Nuclear devices should be exploded under ground.
Production of radio isotopes should be minimized.
Extreme care should be exercised in the disposal of industrial waste
contained with radionuclides.
Use of high chimney and ventilations at the working place where
radioactive contamination is high.
Nuclear medicines and radiation therapy should be applied when
absolutely necessary and earth minimum doses.
Fission reactions should be minimized.
