Post on 21-Jul-2020
2do Foro Peruano-Alemán de Minería y Recursos Minerales“Extracción de Materias Primas y Desarrollo Sustentable”
Bergbauabfälle: (Alt-)Last oder Chance?
Mining residues: legacy or chance?
Dr.-Ing. Sven-Uwe Schulz
Deutsche Rohstoffagentur (DERA) in der
Bundesanstalt für Geowissenschaften und Rohstoffe (BGR)
2do Foro Peruano-Alemán de Minería y Recursos Minerales“Extracción de Materias Primas y Desarrollo Sustentable”
Federal Institute for Geosciences and Natural
Resources (BGR):
central geoscientific authority providing
advice to the German Federal Government in
all geo-relevant questions
subordinate to the Federal Ministry for
Economic Affairs and Energy (BMWi)
2do Foro Peruano-Alemán de Minería y Recursos Minerales“Extracción de Materias Primas y Desarrollo Sustentable”
Raw Materials Information
and Analyses
Contribution for Securing Raw Materials
Supply
1.
Raw Materials Information System
2.
Risk Assessment
3.
Raw Materials Potentials
4.
Diversifying Supply
Development of Strategies for Security of Supply, Network Building, Raw Material Dialogues, Industry Workshops, Conferences
Organization of the German Raw Materials Efficiency Award
Se
rvic
es
Improving market transparency in the mineral resources sector by
providing minerals information and analysis and advise companies
about price and supply risks
Sustainable and Secure Supply of Mineral Resources for Germany
Ta
rge
ts Professional backing of measures taken by
the German government and companies
to secure raw materials supply
Mineral Economics Evaluation of Mineral Resources
German Mineral Resources Agency (DERA): Mission
2do Foro Peruano-Alemán de Minería y Recursos Minerales“Extracción de Materias Primas y Desarrollo Sustentable”
The German Government‘s raw materials strategy
improvement of access to raw materials for the
German industry
helping German industry to diversify its sources of
raw materials
establishing bilateral raw material partnerships with
selected countries
developing technologies and instruments to improve
the conditions for recycling and substitution
helping industry to develop synergies through
sustainable economic activity and enhanced
materials efficiency
creating transparency and good governance in raw
materials extraction
integrating national measures with European policy
on raw materials
2do Foro Peruano-Alemán de Minería y Recursos Minerales“Extracción de Materias Primas y Desarrollo Sustentable”
Common residue types during material use (direct)
source: after Rankin, W. J. (2011)
leach residues,
el.-refining residues,
slag, fume, furnace
refractories
(from furnaces)
solids
liquids
gases
Acid Rock Drainage
(from tailings)
tailings
CO2
(from fuel combustion)
Acid Mine Drainage
(from mines & heaps)
waste rock,
dust
acid/alkaline solutions
from leach residues,
cyanide containing
solutions (Au)
CO2, SO2, NOx, etc.
(from smelting)
In-plant scrap,
dross,
mill scale
pickling liquids, electro-
plating liquids
CO2
(from furnaces)
el. arc furnace dusts,
dross from Al-recycling
Waste process solutions
containing metals
CO2, NOx etc.
(from furnaces)
numerous types of waste during
recycling of scrap metals, electronic
scrap, consumer goods etc.
MiningProcessing
(Benefciation)
Chemical
Transformation
Fabrication &
manufactureRecycling
(Beneficiation)
2do Foro Peruano-Alemán de Minería y Recursos Minerales“Extracción de Materias Primas y Desarrollo Sustentable”
Common residue types during material use (indirect)
source: after Rankin, W. J. (2011)
leach residues,
el.-refining residues,
slag, fume, furnace
refractories
(from furnaces)
solids
liquids
gases
Acid Rock Drainage
(from tailings)
tailings
CO2
(from fuel combustion)
Acid Mine Drainage
(from mines & heaps)
waste rock,
dust
acid/alkaline solutions
from leach residues,
cyanide containing
solutions (Au)
CO2, SO2, NOx, etc.
(from smelting)
In-plant scrap,
dross,
mill scale
pickling liquids, electro-
plating liquids
CO2
(from furnaces)
el. arc furnace dusts,
dross from Al-recycling
Waste process solutions
containing metals
CO2, NOx etc.
(from furnaces)
numerous types of waste during
recycling of scrap metals, electronic
scrap, consumer goods etc.
MiningProcessing
(Benefciation)
Chemical
Transformation
Fabrication &
manufactureRecycling
chemical wastes from explosives manufacture or
from reagent manufacture
fly ash from electrical power generation
CO2 from several process steps:
mainly electrical power generation, explosives manufacture
(Beneficiation)
2do Foro Peruano-Alemán de Minería y Recursos Minerales“Extracción de Materias Primas y Desarrollo Sustentable”
Accumulation of (solid) waste materials through the mining process
Darstellung NICHT maßstäblich / image NOT in scale
Metall
Metal
Schlacke(n)
Slag(s)Konzentrat(e)
Concentrate(s)
Bergbau
Mining
Aufbereitung
(Ore) Processing
Grubenwasser
Mine water
Abraum
Overburden
Abgänge
Tailings
Abwasser
Waste water
Berge
Waste rock (gangue)
Hütte
Smelter
Lagerstätte
Deposit
Roh(erz)förderung
Run-off-mine (ROM) ore
Vorräte
Inventory
Abraum-/Berge-Halden
Waste rock dumps
Aufbereitungshalden / Schlammteiche
Tailings dams & ponds
Schlackehalden
Slag dumps
2do Foro Peruano-Alemán de Minería y Recursos Minerales“Extracción de Materias Primas y Desarrollo Sustentable”
Composition of typical solid wastes during copper production (wt%)
sourc
e: aft
er
Rankin
, W
. J. (2
011)
0,1
% -
0,4
%
3%
-7
%
1%
-4
0%
11
%
1%
-2
%
3%
-5
%
28
% -
35
%
0,0
3%
-2
%
0,1
% -
74
%0
,3%
-1
1%
1%
-1
,5%
0,5
% -
4,5
%
0,3
% -
8,5
%
0,3
% -
0,7
%
37
% -
44
%
28
% -
33
%
0,5
% -
27
%
4%
-2
9%
7%
-1
2%
1%
-1
3%
0,3
% -
45
%
0,6
% -
1,6
%
1,5
% -
12
%
0,0
2%
-0
,4%
0,0
4%
-2
%
0,2
% -
0,8
%
0
10
20
30
40
50
60
70
80
Cu
Fe S
Al2
O3
Mg
O
Ca
O
SiO
2
As
Pb
Mo
Zn
Sb Bi
Cd
Cu
Fe S
Al2
O3
Mg
O
Ca
O
SiO
2
As
Pb
Mo
Zn
Sb Bi
Cd
Cu
Fe S
Al2
O3
Mg
O
Ca
O
SiO
2
As
Pb
Mo
Zn
Sb Bi
Cd
Cu
Fe S
Al2
O3
Mg
O
Ca
O
SiO
2
As
Pb
Mo
Zn
Sb Bi
Cd
waste rock Flotation Tailings Final slag (discarded) smelter dust and fumes
waste rock flotation tailings final slag
(discarded)smelter dust & fumes
2do Foro Peruano-Alemán de Minería y Recursos Minerales“Extracción de Materias Primas y Desarrollo Sustentable”
Quantities (indicative) of solid wastes during production of 1 ton Au, Cu, Al
source: after Rankin, W. J. (2011)
Gold Copper
(heap leaching)Aluminium
ore grade 2 ppm Au 1 wt% Cu 35 wt% Al
waste rock : ore ratio 0,5 3 1
recovery
mining 90% 90% 90%
processing 100% 95% 90%
leaching 85% 85% 90%
electro-winning 100% 99% 100%
Total (overall recovery) 77% 72% 73%
rock waste and ore left unmined 390.000 429 4,31
tailings (dry basis) - 25,9 0,75
leaching residues 590.000 97,5 0,89
electro-winning residues - 0,1 -
total (tons waste per tonne product) 980.000 553 5,95
2do Foro Peruano-Alemán de Minería y Recursos Minerales“Extracción de Materias Primas y Desarrollo Sustentable”
Annual amount of mining related wastes in Germany
48,2 49,2 45,5 46,7 50,5 52,3 42,0 42,9 39,3 27,5 36,9 34,7 30,3 29,3 30,2
358,5
34
6,0
33
5,8
319,7
28
8,9
27
9,6
298,9
30
8,2
30
5,3
294,8
29
5,8
30
8,1
30
3,3
30
9,4
32
0,1
0
50
100
150
200
250
300
350
400
450
2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014
an
nu
al
am
ou
nt
of
waste
in
mn
to
nn
es
mining related wastes other wastes*
sourc
e: S
tat. B
undesam
t(2
016)
* exkluding wastes from waste treatment plants
2do Foro Peruano-Alemán de Minería y Recursos Minerales“Extracción de Materias Primas y Desarrollo Sustentable”
Mining and smelter related residues in Germany
source: r³ joint project REStrateGIS (2015)
resource cadaster for stockpiles (mine waste and smelters) for Germany
joint project of several scientific institutions funded by Ministry of Education and Science
additional analytics and modelling for estimation of inventory
2do Foro Peruano-Alemán de Minería y Recursos Minerales“Extracción de Materias Primas y Desarrollo Sustentable”
Mining and smelter related residues in Germany and their mineral potential
source: r³ joint project REStrateGIS (2015)
more than 1,000 stockpiles in Germany
app. 250 included
app. 250 mn tons of material considered
element
theoretical potential technical potential
min. (mn t) max. (mn t) min. (mn t) max. (mn t)
iron 4.11 44.86 0.62 6.,73
non-ferrous metals 0.46 22.70 0.07 3.40
steel alloys 0.35 8.14 0.05 1.22
critical raw materials 0 0.18 0 0.03
2do Foro Peruano-Alemán de Minería y Recursos Minerales“Extracción de Materias Primas y Desarrollo Sustentable”
Legal framework in Germany
Federal Mining Law (BBergG)
Environmental Laws (forests, water ...)
Life-Cycle management act (KrWG)
...
prevention
preparing for re-use
recycling
recovery
disposal
2do Foro Peruano-Alemán de Minería y Recursos Minerales“Extracción de Materias Primas y Desarrollo Sustentable”
Handling and management of mining residues - good practise
http://www.fch.cl/wp-content/uploads/2016/08/Buenas-Practicas-en-la-Gestion-de-la-Estabilidad-Quimica-en-la-Industria-Minera.pdf
2do Foro Peruano-Alemán de Minería y Recursos Minerales“Extracción de Materias Primas y Desarrollo Sustentable”
Handling and management of mining residues - good practise
http://www.fch.cl/wp-content/uploads/2016/08/Buenas-Practicas-en-la-Gestion-de-la-Estabilidad-Quimica-en-la-Industria-Minera.pdf
1
2do Foro Peruano-Alemán de Minería y Recursos Minerales“Extracción de Materias Primas y Desarrollo Sustentable”
Rehabilitation of the former uranium open pit mine Lichtenberg
Build up of a landscape construction
mining operation between 1958 & 1976
final open pit depth 230 m
cumulative production app. 15 mn tons uranium ore,
resp. 12.670 tons uranium metal
rehabilitated area 2015ultimate pit Lichtenberg 1991
2do Foro Peruano-Alemán de Minería y Recursos Minerales“Extracción de Materias Primas y Desarrollo Sustentable”
Rehabilitation of the former uranium open pit mine Lichtenberg
backfill with stockpile material classified by acid mine drainage potential A (high) to C (low)
minimization of radiologic and chemical influence on air and waters (underground and surface)
zone C
zone B
zone A
backfill model
open pit Lichtenberg
stockpile block model
Backfill concept
2do Foro Peruano-Alemán de Minería y Recursos Minerales“Extracción de Materias Primas y Desarrollo Sustentable”
Chances and potentials of mining residues
“There are some miners who wash over the
dumps from exhausted and abandoned mines,
[…]; and others who smelt the old slags; from all
of which they make an ample return.“
„Etliche Bergleute beschäftigen sich auch damit,
die Halden, die einst aus den Gruben gefördert
und damals gering geschätzt wurden, […] zu
waschen; andere schmelzen alte Schlacken.
Sie ziehen daraus nicht selten sogar einen recht
reichen Gewinn.“
Georgius Agricola (1556): De Re Metallica Libri XII
2do Foro Peruano-Alemán de Minería y Recursos Minerales“Extracción de Materias Primas y Desarrollo Sustentable”
Motivation for (re-)evaluation of the potential of mining dumps and tailings
high prices
increased demand for previously not processed byproducts
new/improved processing technology
environmental aspects
safety/stability
2do Foro Peruano-Alemán de Minería y Recursos Minerales“Extracción de Materias Primas y Desarrollo Sustentable”
Examples of BGR/DERA work in the field of potentials assessment
Chromite & PGE potentials in tailings of the Bushveld complex, South Africa
evaluation of copper tailings in Chile
interdisciplinary 3D investigations on tailings impoundments
bioleaching of metal sulfides in mine waste
regional cooperation for sustainable mining
2do Foro Peruano-Alemán de Minería y Recursos Minerales“Extracción de Materias Primas y Desarrollo Sustentable”
Chromite & PGE potentials in tailings of the Bushveld complex, South Africa
PGE: operation
tailings
Chrome: operation
tailings
tailings
average grade material
[mn t]
PGE
[Moz]
Cr2O3
[mn t]PGE
[ppm]
Cr2O3
[%]
PGE operations 0.65 5 – 10 2,089 39 172
Chromite operations 2.25 20 43.5 2.8 8.7
total 2,132.5 41.8 180.7source: DERA 2015
2do Foro Peruano-Alemán de Minería y Recursos Minerales“Extracción de Materias Primas y Desarrollo Sustentable”
Chromite & PGE potentials in tailings of the Bushveld complex, South Africa
source: DERA 2015
Mooinooi, tailings
Millsell, tailings
Impala, tailings
Tailings from chromite mining Tailings from PGE mining
Impala, tailings
2do Foro Peruano-Alemán de Minería y Recursos Minerales“Extracción de Materias Primas y Desarrollo Sustentable”
Chromite & PGE potentials in tailings of the Bushveld complex, South Africa
source: DERA 2015
Western limb 81%
Eastern llmb 10%
Northern limb 9%
171.83 Mt Cr2O3
Chromite and PGE potential in tailings
from PGE mining:
Western limb 83%
Eastern limb 10%
Northern limb 7%
38.8 Moz PGE
Chromite and PGE potential in tailings
from chromite mining:
Western limb50%
Eastern limb44%
North.limb6%
8.64 Mt Cr2O3
Western limb50%Eastern
limb43%
Northern limb7%
2.8 Moz PGE
2do Foro Peruano-Alemán de Minería y Recursos Minerales“Extracción de Materias Primas y Desarrollo Sustentable”
Evaluation of copper tailings in Chile
definition of selection criteria
(Tonnage, age of tailings, metal content,
ownership, legal questions)
pre-screening of the available information,
sampling of selected tailings selection of 1 – 2
demonstration projects
in-depth analysis of selected demonstration
projects
(chemical and mineralogical analyses, drilling,
bio-leaching tests)
economic evaluation and environmental impact of
potential reprocessing & rehabilitation
continuous exchange of information with
companies, potential investors, government
2do Foro Peruano-Alemán de Minería y Recursos Minerales“Extracción de Materias Primas y Desarrollo Sustentable”
Evaluation of copper tailings in Chile (part 1 in 2014-2015)
12 mine sites visited
81 samples analyzed for main and trace elements
copper grades between 0.1 % and 3.7 %
in some special layers
further elements of economic interest are among
others:
Fe, Au, Mo, Zn …
selection of 4 sites for deeper investigation
4 samples each 20 – 30 kg tailings material, were
taken from:
Minera Clarita (Cu-Au, 5 mn t),
Taltal (Cu, 2 mn t, Enami),
El Salado (Cu-Au, 1 mn. t Enami),
Minera Carola (Cu, 30 mn t)
2do Foro Peruano-Alemán de Minería y Recursos Minerales“Extracción de Materias Primas y Desarrollo Sustentable”
Evaluation of copper tailings in Chile (part 1 in 2014-2015)
results:
to be continued in 2016 - ...
dump no. tailings Cu conc. recoveryCu content
(real)
value
@ 4.500 US$/t
value
@ 5.500 US$/t
1 1 mn t 0.40% 60% 2,400 t $10,800,000 $13,200,000
2 2 mn t 0.45% 70% 6,300 t $28,350,000 $34,650,000
3 2 mn t 0.47% 84% 7,896 t $35,532,000 $43,428,000
4 5 mn t 0.12% 50% 3,000 t $13,500,000 $16,500,000
5 5 mn t 0.11% 66% 3,630 t $16,335,000 $19,965,000
2do Foro Peruano-Alemán de Minería y Recursos Minerales“Extracción de Materias Primas y Desarrollo Sustentable”
Interdisciplinary 3D investigations on tailings impoundments
Recoverability of raw materials from complex tailings
Complexity of internal tailings structure:
depositional fractionation of minerals by grain size, density or shape
partial weathering affecting minerals, minerals surfaces and texture
changes of source material or mineral treatment techniques
Target exploration requires suitable methods to understand :
internal structure due to deposition and alteration
enrichment/depletion processes
mineral surface conditions and mineral assemblages
Methods to achieve goals:
2D mineralogical and chemical investigations
2D hyperspectral imaging
tomographic geophysical investigations
3D CPT-EDXRF measurements
Sampling at Los Ninos tailings (Cu) in Copiapó (CHL)
EDXRF M4-Tornado element distribution showing
texture and a Cu-enriched zone; from Los Ninos
2do Foro Peruano-Alemán de Minería y Recursos Minerales“Extracción de Materias Primas y Desarrollo Sustentable”
Bioleaching of metal sulfides in mining wastes
Biomining (applied geobiotechnology of bioleaching):
extraction & recovering of valuable metals from sulfidic ore deposits
app. 15 % of world copper production from bioheapleaching
mainly in Chile
more than 40 years experience in R&D on bioleaching of metals from different ores and residues at BGR
e.g. > 100 scientific publications on copper shale, mine tailings, ashes
BGR R&D results:
mining residue dumps and tailings e.g. in Chile and Peru with significant amounts of valuable metals, extractable via bioleaching
Mine waste tailings at Ticapampa in PeruBioreactor in BGR lab
2do Foro Peruano-Alemán de Minería y Recursos Minerales“Extracción de Materias Primas y Desarrollo Sustentable”
program of the German
Federal Ministry for Economical
Cooperation and Development in the
Andean countries:
Bolivia
Chile
Colombia
run by GIZ and BGR
main goals:
economic sustainability
design and implementation of policies, strategies and incentives for sustainable use of mineral
raw materials
ecologic sustainability
support for the adoption of modern environmental technologies (water/energy management,
renewable energies, treatment and management of mining residues (PAM)
social sustainability
development of a structured cooperation between all stakeholders in the mining context
(dialogues, negotiations, practices and instruments of mediation)
Regional cooperation for sustainable mining –
Example: Pataz, La Libertad, Perú
Ecuador
Peru
Photo: L. Winkelmann, BGR
2do Foro Peruano-Alemán de Minería y Recursos Minerales“Extracción de Materias Primas y Desarrollo Sustentable”
“Se precisa una forma de pensar
completamente nueva para resolver los
problemas que hemos creado con
nuestra vieja manera de pensar.”
¡Muchas gracias! Thank you very much! Vielen Dank!
“The world we have created today has
problems which cannot be solved by
thinking the way we thought when we
created them.”
„Probleme kann man niemals mit
derselben Denkweise lösen, durch die sie
entstanden sind.“
Albert Einstein