Environmental Balance of Technological Options in Mining

1. Environmental Balanceof Technological Options in Mining Presenter: Carsten Drebenstedt 1

2. Outline • Definition and Methodology • Case Study • Application • Results/Summary 2

3. Definition of Environmentally-friendly Mining System The application of environmentally - friendly mining techniques means : A: Avoiding or Minimizing - emissions into the atmosphere (exhaust gas, dust) - noise - vibration - the contamination of the ground and surface water (and thus maintaining the water quality) and - the creation of by - products (especially the share of non – marketable raw materials) B: Reducing - the consumption of consumables (fuel, power, explosives, lubricants) - the wear and tear - the temporary use of land (earlier reclamation/renaturalization) - the visual impairment of the landscape concerned and - the production losses (careful use of resources) 3

4. Mining technique and environmental, economic and social effects 4

5. Technology Selection Methodology 5

6. Input Output Deposit (primordial natural area) raw materials for the economy extraction system (equipement for loosing, loading and conveying, primary crushing, auxiliary operations) changed natural area material emission into the air, water, ground noise consumables (electric energy, sources of energy, explosives and other things) vibrations non-utilizable overburden planning of mining operations waste waste-water non-intentional outputs (NIO´s) utilization of the deposit (field, extraction and preparation losses, utilization of associated raw materials) Input – Output Analysis 6

7. Mining techniques D rilling & C utting B reaking R ipping M illing blasting horizontal verti c al horizontal verti c al h ydrauli c - hy drauli c - s u r face - buck et - wheel bull dozer face miner hammer ex c avator m iner excavator Case Study:Extraction Techniques for Hard Rock 7

8. Extraction systems I 8

9. Extraction systems II 9

10. Extraction Techniques for Hard RockCriteria for Application ++ very high/good, + high/good, 0 moderate, - low/not recommended 10

11. Extraction Techniques for Hard RockOutput vs. Compressive Strength 11

12. Extraction Techniques for Hard RockOutput vs. Weight 12

13. Input-Output analysis, on example of using vertical ripping 13

14. Alternative Ai A1 A2 A3 A4 Ai Criterion j Weighting k1j k2j k3j k4j k5j U1 g1 p11 p21 p31 p41 p5i U2 g2 p12 p22 p32 p42 p5i Uj gj p13 p23 p33 p43 p5i Σp1j*gj*k1j Σp2j*gj*k2j Σp3j*gj*k3j Σp4j*gj*k4j Σpij*gj*kij UEges i= Evaluation matrix 14

15. Weighting of Environmental Effects 15

16. Calculation Equations - Environmental Effects - Environmental, Economic and Social Effects 16

17. Application • Loosening, loading, hauling • Loaded with wheel loader with a bucket of 5 m³ • Vertical ripping, horizontal milling, cutting without any loading equipment • Bucket wheel excavator, face miner required electrical, all other extraction systems diesel fuel • Fissured rock formation with UCS of 20 MPa • Loosening capacity has been fixed at 300.000 t/a 17

18. Environmental effects and costs of the mining technique (quantity units) 18

19. Weighted environmental effects caused by the far-away open-cast mine 19

20. Weighted environmental effects and costs caused by a near open-cast mine 20

21. 200 180 160 140 120 Influencing variable [-] 100 80 60 40 20 0 vert.ripping drill. & blast. cutting breaking horiz.ripping horiz.milling vert.milling Mining techniques W+UEfar away W+UEclose by W UEfar away UEclose by Environmental effects and the costs after scaling the results 21

22. Result/Summary • The presented methodology for selection of most environmental friendly mining technique considers objective (measured or calculated) criteria and expert knowledge (weighting) • The methodology considers economic and social effects • The case study shows logical results • There is now opposite between environmental-friendly and economical aspects 22