Uranium Mining

Something has to start from somewhere...

So does the story of Nuclear...

And the story begins with - Mining.

Mining as we all know is the extraction of minerals or other geological materials from the earth.

In the case of uranium mining, the minerals extracted  = uranium ore.

Basically, there are several ways uranium can be mined.

This includes:-

- Open surface or Open pit mining.

- Underground mining.

- In-situ leaching.

Why several ways?
Well, it all depends on factors such as:-
- Depth.
- Size of the ore body.
- Type of rock formation which the ore is found.

In short:-
- Open pit mining is the conventional type.
- Underground mining is the least safe of all three methods.
- In-situ leaching is less costly to build and operate. It also has a number of advantages over the other two mining types.

But again, mining technique depends on the condition in which the ore is found.

Open pit mining
- Google image -

Underground mining
- Google image -

In situ leaching
- Google image -

Something to ponder 2

This is Part 2 of our previous entry

Type of Power Plant	Fuel for 1,000 MWe for 1 year
Solar	100 KM2 area
Wind	3,000 WIND TURBINES of 1 MWe
Biomass	30,000 KM2 of plantation area
Bioalcohol	16,100 KM2 of corn
Biogas	800 MILLION chicken

- Info from Malaysian Nuclear Agency (Nuclear Malaysia) -

D day

11/10/10

The radioactive day i would say.. :)

Its our Nuclear subject test!

Many topics to cover..and lots of things to memorize.

The questions given was a bit tough though...

Personally, i didn't manage to answer all the question.. :(

Luckily, we were given tips for the test.

Thanks to our lecturers for the useful tips.

It really helps!

We were also allowed to bring a piece of cheat sheet*.  :)

Whatever it is, past is past..

Strive for better tomorrow!

*cheat sheet* - A piece of A4 paper which we can write anything and bring it to the test.

P/s : Sir, please give us good grades... :)

The famous equation

E = mc2

So, what is this famous equation by Einstein is all about?

Well, the equation says that matter (m) and energy (E) are two forms of the same thing.

The speed of light (c) which is constant, is an enormous number.

So basically, Einstein's equation shows that a very tiny amount of matter is the same as a huge amount of energy.

The equation is a direct result of Einstein's work on the special theory of relativity.

Something to ponder...

Type of Power Plant	Fuel for 1,000 MWe for 1 year
Coal	2 MILLION TONNES of coal
Fuel Oil	1.96 BILLION GALLONS of oil
Natural Gas (Combined Cycle)	87.6 BILLION SCF of gas
Nuclear (fission)	30 TONNES of uranium
Thermonuclear (fusion)	0.6 TONNE of tritium/hydrogen

-Info by Malaysian Nuclear Agency (Nuclear Malaysia)-

Control Rods

As the name says, Control Rod is a control device that is use to provide precise and adjustable control of reactivity in the reactor core.

When reactivity is controlled, the power output is also controlled.

Basically, control rods function by absorbing neutrons from generating another nuclear reaction.

Nuclear reaction or fission generates heat.

If the heat generated is not controlled, overheating will occur.

This will make the the reactor components such as the fuel rods melt.



Control rods also function as a safety device.

In the event of emergengy, control rods can be release completely to shut down the reactor.

Control rods materials:-

• Silver, Ag
• Indium, In
• Cadmium, Cd
• Boron, B
• Hafnium, Hf

In a more proper way of writing, the purpose of control rods includes:-

1. Coarse control and/or to remove reactivity in relatively large amounts - Shim rods.
2. Fine control and to maintain desired power or temperature - Regulating rods.
3. Provides fast shut down in the event of unsafe and emergency condition - Safety rods.



Image from Google

-Click for larger view-





Image from Google
-Click for larger view-



 



   







 

Image from Google
-Click for larger view-



Again, we can see that Nuclear Reactor is full of safety features!

:)







Reactor Safety Systems and Why Is A Reactor Safe?

Okay..lets talk about safety.

The most important aspect of a Nuclear Reactor.

What is Nuclear Reactor?

Nuclear Reactor is an engineering device, in which nuclear fuel and structural material are arranged such that a self-sustained fission chain reaction can occur in a controlled manner.

New and advanced reactors are designed with safety in mind, including the development and application of Passive Safety Systems as far as possible.

It requires no operator intervention in the event of major malfunction.

Passive Safety Systems depends only on physical phenomena such as pressure differentials, convection, gravity or the natural response of materials to high temperatures to slow or shut down the reaction, not on the functioning of electrical or mechanical operation on command systems.

Other safety provisions includes a series of physical barriers between the radioactive reactor core and the environment, the provisions of multiple safety systems, each with backup and designed to accommodate human error.

The barriers in a typical plant are:

1. Fuel container within the reactor, generally thousands of sealed metal tubes, rods, or plates, fabricated to the highest quality standards.
2. Closed loop of water which transport the fission energy away from the reactor. Water is converted to steam by fission.  The steam passes through a turbine-generator, is condensed and the water eventually returned to the reactor to be reheated.  Note that while this loop serves to generate steam, it also serves to cool the reactor, keeping it in thermal equilibrium.  Should one or more fuel elements fail, mechanically or due to overheating, the fission fragments would be contained in the closed cooling water loop.
3. Most reactors (except the Chernobyl type) have a third barrier, called a containment building.  It is a large steel lined, concrete structure completely enclosing the reactor and it’s cooling loops.  It is designed to completely contain all of the coolant should a major failure leak occur in the cooling loops, and all of the water flashed to steam.  So even if fission fragments were released into the cooling loop and the loop leaked, fission fragments would be held in the containment building.

So, Is a Reactor safe?

The answer is simply Yes!

P/s:- It should be emphasize that a commercial type Nuclear Reactor simply cannot under any circumstances explode like a Nuclear Bomb. :)