- August 6, 2019
- Posted by: docmedia
- Category: News
JOHANNESBURG – We have heard a great deal about the price of coal recently and how critical the coal price is to the production of electricity at a coal-fired power station. This is rather obvious.
What people are generally very unaware of is how nuclear fuel works. Yes, people have heard of uranium going into a nuclear reactor. But you don’t throw blocks of uranium into a reactor, like charcoal on the braai.
The uranium is fabricated into “fuel elements”. The traditional type is a group of tubes about as thick as a finger. These tubes, with a uranium oxide in them, are known to the public as “fuel rods”. A group of fuel rods tied together, form a fuel element.
Reactors such as those at Koeberg near Cape Town run on fuel elements almost four metres in length and with a cross-section about the size of two loaves of bread.
A critically important factor with nuclear fuel is that to the eye the element that goes into the reactor looks exactly the same as when it comes out, after 18 months of life. There is no waste ash, or gas given off, or residue of any sort.
The invisible difference is that many of the uranium atoms have split to become other atoms, giving of vast quantities of energy as they do this.
It is possible, but not legal, for two people to carry a fuel element before it goes into a reactor, with no harm. When it comes out it is a different matter. It is then so radioactive that it would kill anyone who tried to go near it. So they are handled very professionally.
However South Africa pioneered another type of fuel for the South African developed Pebble Bed Modular Reactor (PBMR) which is a small reactor designed to be able to be placed inland in dry areas, perfect for some African conditions.
This fuel also contains uranium but in the form of grains about as large as grains of sugar. These grains are very specially made and then individually coated, like chocolate Smarties, using a unique South African process. The grains are then bonded into a graphite ball about the size of a cricket ball. These balls go into the reactor, essentially in a big tank. They last about three years and then come out looking the same as when they went in.
But amazingly a single person can hold in his two hands enough balls to provide the total electricity for his entire lifetime. PBMR fuel balls have been fabricated in South Africa. There is huge export potential just in selling this fuel worldwide. A nuclear future is waiting.
Originally published on: www.iol.co.za