§ 4.2.4 Separating Minerals by Floatation and Vibration
It's possible to separate some minerals by their density, once we have a sieved collection of grains of the same size.
Just vibrating a bed of same sized grains will separate mineral grains into layers fairly well based on their "weight" in a centrifuge or in lunar gravity. The denser grains fall to the bottom.
Pouring material into a liquid of intermediate density will quickly separate a desired grain by floatation, though it must be dried thereafter and the fluid recycled. Floatation can be fine tuned based on the theory discussed below.
In orbital space, zero gravity helps in this process, as a centrifuge can provide different levels of artificial gravity as different minerals settle at different rates.
The quick & dirty theory on floatation
Floatation is based primarily on surface phenomenon, not the specific gravity of the mineral.
Different materials have different affinities to a selected liquid and the air bubbles introduced. The surface tension of the liquid is essential to fully understanding the process. Frothing reduces the surface tension of the liquid. Of interest is minerals' "wettability" or repellant properties, relative degree of readiness to adhere to bubbles, and affinity for certain types of chemical compounds or reagents.
Sulphide minerals of all types and sizes are the most easily floatable.
On Earth, floatation is often opted because of its simplicity, selectivity and flexibility. Frothing and separation processes may be fairly interesting in low gravity. The downside in space is the need to stringently recycle the liquid used for the floatation, as long as volatiles remain in short supply in earth orbit.
The quick & dirty theory on "gravity concentration"
There are two processes at work:
- Small particles tend to settle at the bottom, and large particles at the top.
- Given particles of the same size, heavier particles (i.e., higher specific gravity) will settle down further.
PERMANENT.com > Manufacturing, Industry > Materials Processing > Vibration and Flotation
Reasons to do something yourself:
- It will help save life on our special planet -- be part of the solution in your generation.
- It will create and secure a better future for your children and grandchildren.
- It could be an interesting, cool, and a fun adventure for your life!
You can join us and volunteer to help out,
... or ...
If you're short on time, you can just donate:
The Permanent Space Development Foundation, Inc., is a 501(c)(3) nonprofit organization.
If you would like to make a quick donation to our humanistic cause,
then please click on one of the buttons below (which go to PayPal).
... or by cryptocurrency (which is NOT tax deductible), you can donate into any of these wallets:
... or ...
Suggest this website to other people and organizations.
To get updates on PERMANENT (occasional, not frequent), get on our mailing list.
For general or specific e-mail regarding PERMANENT, please use our Feedback page.
Leave information about yourself in our people, companies, and organizations database.
If you are interested in hiring our expertise, anywhere in the world, please contact us.
We have people in the USA and Thailand, and can travel or consult by internet.
You can call anytime, 24/7, at +66-8-1135-7977
Text by Mark Prado, Copyright © 1983-2018, All Rights Reserved.
Many website artistic design elements by Sam Fraser, Copyright © 1999-2018, All Rights Reserved.
Except where specifically stated otherwise,
Copyright © 1983-2018 by Mark Evan Prado, All Rights Reserved
P rojects to E mploy R esources of the M oon and
A steroids N ear E arth in the N ear T erm
please see our
For PCs, this righthand
side has a floating menu,
but if your tablet
or your PCs web browser
do not run
then you must
-- navigate --
using the Site Map above.