Safety Aspects In Nuclear Reactors

Question 1

what fuel is used in nuclear reactors?

Answer 1

Enriched uranium (consists of uranium-238 (primarily) and 235)

Question 2

What proportion of uranium-235 is in enriched uranium?

Answer 2

2-3%

Question 3

What does uranium-238 help do?

Answer 3

Absorbs fission neutrons to serve to help control the rate of fission.

Question 4

How are control rods inserted into the reactor? And why so?

Answer 4

remotely. To limit the level of radiation workers are exposed to.

Question 5

why do nuclear reactors have emergency shutdown systems?

Answer 5

designed to drop the control rods into the core.

Causes all the free neutrons in the core to be absorbed, and hence completely stopping nuclear fission as quickly as possible.

Question 6

What is shielding? And what is it usually made form

Answer 6

Shielding around reactor’s core to protect workers from hazardous radiation.

Made form concrete which is sufficient to block the wide range of radiation produced in the core. Including alpha and beta particles, gamma, neutrinos and neutrinos. Shielding may become radioactive after long term use, and must be properly disposed to prevent environmental damage.

Question 7

What determines how radioactive waste is stored?

Answer 7

The classification

Level of reactivity, physical form and the duration of its hazard.

Question 8

How is Low-level waste stored? E.g. contaminated protective clothing and tools

Answer 8

Supposed of close to the surface in metal drums buried in trenches

Question 9

How is Intermediate-level waste stored? E.g. used reactor components and resins

Answer 9

Stored in drums encased in concrete that are placed within specifically constructed reinforced buildings with concrete walls.

Question 10

How is High-level waste stored? E.g. spent nuclear fuels and radioactive by-products from reprocessing.

Answer 10

Removed remotely and placed in cooling ponds (for up to a year) as the waste is initially very hot.

Any recyclable plutonium or uranium is then removed.

In liquid form this waste may leak, and hence it is vitrified. (Mixed with molten glass to form a durable, solid material).

then placed in stainless steels containers and stored deep underground in geologically stable areas.

Question 11

what are some risks and benefits associated with nuclear power?

Answer 11

Risks:

Nuclear reactors must be designed incredibly carefully in order to minimise the possibility of a nuclear disaster.

Substantial amounts of dangerous radioactive waste is produced, which must be dealt with in a way which does not endanger people our the environment.

Benefits:

Reliable production of power
Produce no pollutants
Require far less fuel to fossil fuels