1 / 20

Intro to Mining Resources

Intro to Mining Resources. Key Concepts in this Unit: Obtaining metal resources from the earth is a very involved process. Many things need to be taken into consideration when deciding whether or not to open a mine. The products that we use everyday come from the earth.

aren
Télécharger la présentation

Intro to Mining Resources

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Intro to Mining Resources Key Concepts in this Unit: Obtaining metal resources from the earth is a very involved process. Many things need to be taken into consideration when deciding whether or not to open a mine.

  2. The products that we use everyday come from the earth

  3. We all know that products don’t just get dug out of the ground…

  4. …But many people don’t realize that even the raw materials we use to make products must be processed before they are usable when they are dug out of the ground.

  5. CASE STUDY • What does it take to get the Aluminum that makes up this can?

  6. About Aluminum… • Third most abundant element in earth’s crust (after oxygen and silicon) • Has a low density for a metal and resists corrosion. • Based upon this chemical structure, will it be found in nature as pure Aluminum? • NO

  7. Aluminum is present in a high quantity in the rock of this area... So how do you get the resource?

  8. Either dig a tunnel underground… • But this can… • be dangerous (collapse potential, build up of harmful gases, high exposure to dust) • be difficult to efficiently get the resource to the surface

  9. …OR strip away the surface (open pit mine) • But this can cause a significant disruption of the ecosystem of the area.

  10. Once the vegetation and soil is removed, you need to loosen up the rock… • HOW?

  11. Once you have loosened the rock by blasting, you can dig out the rock that contains the aluminum. Here’s what it looks like… • This is the rock ‘Bauxite’ (a.k.a. aluminum ore) • It contains the mineral ‘Gibbsite’ (AlOH3). • It also contains other minerals that are not useful.

  12. Removing the Aluminum from the Bauxite requires many steps… • Pulverization-- Rock is crushed into pieces of about 3cm diameter. WHY?

  13. 2) Chemical Separation • Sodium Hydroxide (NaOH) is added in order to dissolve the Aluminum into a liquid as Alumina.

  14. 3) Density Separation The sodium hydroxide solution is stirred around in the giant vat… Heavier rock fragments settle to the bottom. Then the solution is filtered, which separates the waste material from the liquid that contains the aluminum.

  15. The waste material is coated with Sodium Hydroxide. What is NaOH? • Since NaOH is a strong base… • The waste material must be neutralized (by adding acid) before it can be returned back to the environment.

  16. 4) Electrolysis is used to separate the Oxygen from the Aluminum in the liquid Alumina (Al2O3) • Carbon electrodes attract the Oxygen, thus forming Carbon Dioxide & freeing up the Aluminum. • This process consumes about 16,000 KWH of electricity for every ton of Aluminum produced. • For reference, the average home in CT uses 700 KWH of electricity in a month.

  17. So is it worth it to recycle Aluminum cans? Recycling aluminum… • SAVES 95% of the energy needed to make the can • Reduces impact on ecosystems since fewer mines need to be produced

  18. Hungary, October 2010

  19. When the tailings dam burst, a wave up to 7 feet high rushed through the town carrying a very basic solution of toxic metals into the nearby town. • 10 deaths, 120 injuries from this event.

  20. Is this how all metals are produced? • While not all metal resources are processed in the same way, all metals will require several steps to extract and purify the resource.

More Related