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Control of hazardous elements for Sustainability in Non-ferrous
Industry
T.Nakamura
Institute of Multidisciplinary Research for Advanced Materials,
Tohoku University
Please contact to [email protected]
OUT LINE
• Introduction
• Environmental Issues of Extractive Metallurgy
• Important role of control heavy metals in Recycling
• How to control hazardous elements for Sustainability - regulation -
• Conclusions
What happen in the Erath/World? Climate Change?
Shortage of all resources Food, Water, Energy and Mineral Resources ?
or financial instability??
Erath is
so beautiful
How to keep
a Sustainability
for Human Beings
and Nature also
What we have made from old time? History of Artifacts
Human beings can’t live without artifacts
Stone
Steel Carbon Composite
+ all materials
Wood Concrete + Steel
All materials
Weather Sustainable society
“Nature” “Artifacts ”
We are required to take responsibility for the
situation that we have created.
We can forecast but not control any means of altering tomorrow’s weather.
We can prepare for earthquakes and typhoons but we cannot stop them.
Weather
Sustainable society
We all talk about it as a very important issue.
We are at a loss when we try to decide how to achieve it.
Deference between Nature and sustainable society
Classification from aview point of Environmental Issue
Energy Issue (CO2 Emission)
Fe, Al, Ti, Mg, Mn
Cr
Zn
RE
W, Mo,
Ta, Nb,
Ga
Cu, Pb
Sb,Ni
Hazudous Issue
Hg, As, Cd, Tl, Be,Se,B,
I,F,Br
Short Resource
Issue
Au, Ag, PGM,
Bi, Co, In
Climate Change
Resource
Constraint Ecological
Effect
OUT LINE
• Introduction
• Environmental Issues of Extractive Metallurgy
• Important role of control heavy metals in Recycling
• How to control hazardous elements for Sustainability - regulation -
• Conclusions
Aerial views of the alien landscapes of Rio Tinto in Spain, by
Francisco Mingorance
Aerial views of the alien landscapes of Rio Tinto in Spain, by
Francisco Mingorance
Times published the rating of the most polluted cities in the world.
Let‘s see what has changed. 10. Kabwe (Zambia)
http://www.earthobserver.org/category/General.aspx
La Oroya (Peru)
http://www.earthobserver.org/category/General.aspx
Tianying(China)
The smelting of lead (the largest production in China).
Result: The lead content in air is 10 times greater than national standards.
140 000 people constantly exposed to the high content of lead in the
environment.
http://www.earthobserver.org/category/General.aspx
Emission from Uncontrolled Metal Industrial Sectors
SOx , NOx
Acid rain
POPs like Dioxins
Diffusion of very small toxicity substances
Heavy metals : Hg,As,Cd,Pb
We have to stop the emissions of them
Typical Open Mining of Copper
Cu content becomes less 1% in Copper ore.
We have to through away 2/3 of ore in a
mineral dressing process as tails.
Then, we have a large Amount of Ecological
Rucksack to get Primary Resources
We have to handle and treat more than 99%
residue when we produce metallic copper
from Cooper Ore.
Full-scale operation began in
April 1982, and has been
continuous since then,
neutralizing and treating large
volumes of mine wastewater at
around
New neutralization and treatment facility at the abandoned Matsuo Mine
Located in the middle of Hachimantai, 1,000 meters above sea level, the
abandoned Matsuo Mine is the largest sulfur mine in the Far East. The mine site
was discovered as a large outcrop of a sulfur ore deposit in 1882. In its most
prolific period, as many as 15,000 people lived nearby, and the prosperity of the
mine peaked. From the 1960s, however, mine operations worsened due to the
market debut of sulfur recovered cheaply through desulfurization of heavy oil in
response to regulations on pollution; in 1972 the mine was closed. Even after the
mine was closed, however, large volumes of strongly acidic water continued to
flow from the mine and empty into the Red River nearby.
http://www.jogmec.go.jp/english/activities/pollutioncontrol/neutralizationplant.html
In case of Japan
Japanese Mineral Resources in old time
• 1000 years old, iron sward was one of main export goods from Japan
• About 400 years old , main export goods are
Copper, Silver and Gold
Now there is only one gold mine in Japan,
where is located Hishikari, south Kyusyu
Japanese serious pollution disasters on GDP growth
Year
SO2
Hg
As
PCB
DXN
1880-1900
Cd
?
Copper
smelter
Chemical
Industry
Zinc smelter
As mine
oil
Incineration
fly ash
SO2
New air regulation
And water regulation
Law concerning Special
Measures against Dioxins
-4 -3 -2 -1 0 1 2 3 4 5 6 0
1
2
3
4
5
6
7
8
9
10
log K (ppm)
log
T (p
rod
uct
ion
. to
n /
yea
r)
Ⅰ Chalcophile group Ⅱ Siderophile group Ⅲ Lithophile group
group Ⅰ T = 10 5 K
group Ⅱ T = 10 4 K
group Ⅲ T = 2.5x10 2 K
S = M/T = 30 years
S = M/T = 300 years
S = M/T = 1.5x10 4 years
Ⅰ Ⅱ
Ⅲ
Te Pt
Au Se
Hg
Bi
Cd
Sb As
Mo
In
Tl
Be
Ga
Ta Y
Li V Nb
Co W
Sn Ni
Zr
Mg
Al Ca
Ti
Fe
S Cu Zn
Pb Cr
Relationship between Annual Production Amounts and Clarke’s Numbers
How can Metal Production be continued from
Primary Resources
REE
Essence of Separation Technologies
• Two ways are available : Physical Separation
Chemical Separation
• Physical Separation: Mainly solid state separation
Milling, Gravity separation ,Magnetic separation and so on. Good for pre treatments before finial materializing
• Chemical Separation: Using chemical reactions to remove impurities which are contaminated in atomic level to achieve a fine separation.
Leaching, Roasting, Smelting, Electro-Winning and so on
• Best mix of Physical Separation and Chemical Separation
is necessary for high efficient separation
Extraction Process of Copper
(Exploration) (Mining) (Crushing・Milling)
(Concentration) (Concentrate)
(Leaching)
(Solvent Extraction-
Electrowinning) (Electrolytic Copper)
(Smelting) (Refining) (Electrolytic Copper)
Mining
Smelting
→ Residue
↓ Residue
(Tailing )
↓ Residue
(slag, dust )
↓ Flue gas
( Sulfuric acid )
Iron Precipitation
Method
Advantages Disadvantages
Jarosite Process ■Technology widely used
and tested
■Technology for
Immobilization available
■Sulphate control
■High volume of residue,
owing to the resulting low Fe
content
■Long residence time in the
precipitation tanks
■Environmentally unstable
■High cost of residue
disposal
■Environmental concerns
with entrained toxic
contaminants in residues
Goethite process ■Amount of residue lower
than for the Jarosite
process
■Environmentally stable
■Yield of silver lower than
for the jarosite process
■Environmental concerns
with entrained toxic
contaminants in residues
Hematite process ■Residues are of
commercial value if pure
(gypsum and hematite)
■No landfill space required
if residues can be sold
■High cost equipment
■Complex and yet un-
economical technology
Pressure acid leaching ■Simplified iron removal ■High cost equipment
■Complex technology
Solvent extraction ■Very pure cell house
electrolyte
■Simplified neutral
leaching control
■Limited ability for ferric
iron control in SX
(organic tolerates only
low levels of ferric iron)
Comparison of Iron Control Process in Hydro-Processes
• When Copper , Zinc or Lead is collected,
Arsenic accompanies at the same time.
•Non-ferrous smelters can not neglect
Arsenic treatment.
•Copper concentrate was imported into Japan about
3-million MT/year.
•Assuming that average Arsenic content is 1000ppm,
3000MT/year of Arsenic could be brought into
Japan
Why Arsenic ?
Base Metals and Minor Metals recovered from Primary and Secondary Resources in Non-Ferrous Industry
Copper Smelting
Zinc Smelting Lead Smelting
Cu,Au,Ag,PGM. Ni,Co,Cd,As,Se,Te
Pb,Sn,Bi,Sb
Zn,In,Ga
Pb
Cu
Pb
Zn
Zn
Cu
Zinc concentrate
EAF dust
Copper concentrate
Shredder dust
Lead concentrate
Waste lead battery
Fly ash
Sulfuric acid?
More than 20 metals can be recovered except RE,W,Mo,Mn,Cr,Nb,Ta and Li
OUT LINE
• Introduction
• Environmental Issues of Extractive Metallurgy
• Important role of control heavy metals in Recycling
• How to control hazardous elements for Sustainability - regulation -
• Conclusions
Recycling Copper Production of Copper in Japan :1.2 million tons Consumption of Copper in Japan : 0.8 million tons Scrap Copper in Japan 0.5 million tons Recycling Copper in Japan : 0.3 million tons Recycling Ratio to Scrap Copper : 60% Where Is other Copper Scrap? Mostly scrap copper is shipped to foreign country Partly Landfill, If Copper Content is around 3% in Shredder Dust, 45,000 tons of Copper are land-filled.
Shredder dust treatment process in Onahama Smelter
Key Point: Halogens in flue gas are not put into a main acid plant but put into plaster(CaSO4) plant.
Burning zone
Oil Burner
Shredder dust
Copper concentrate
Oxygen enriched air
Smelting zone Settling zone
slag
matte
Boiler Flue gas Treatment
Oxygen plant
Power plant
steam
Recycling of Zinc
Recycling Ratio: 25%
Process :
Zinc melt after Plating
Re-melting in NaOH Flux and Filtration
EAF Dust
Many Dust Treatments Processes are available
Finally Crude ZnO is reduced in ISF process
Technical Problems
①Complicated Recovery Processes
②High Energy Consumption
③Registrated as Industrial Waste
④Dioxins
⑤Low Pries of Zinc
Core-competence of Non-Ferrous Industry for Dust Recycling
* Separation Techniques for heavy metals like Cu,Zn and Pb
* Keep facilities and place to treat dust Short risk communication at the beginning of
commercial operation of Fly Ash, Shredder Dust Treatments
0.1 mass%
Fly Ash
1 mass%
Secondary Fly Ash
10 mass%
Municipal
waste Incinerator
Fly Ash
Bottom
Ash
Smelting
Furnace Secondary
Fly Ash
Zinc
Refinery
Municipal waste
Enrichment Route of Zn from Municipal Waste
Combine Fly Ash treatment with EAF dust treatment
Coal Silica Raw Materials
Dryer
Rod Mill
Briquette
Machine
MF
Boiler Gas Cooler Bag Filter
Removal of Halogen
Filter Press
Aging Bins
Slag
Crude Zinc Oxide
Power Plant
Sell Out Steam
EAF Dust Other Materials
Binder
Fly Ash
Leaching Tank
Thickener
Filter Press
<Cl elimination>
Process flow for recycling fly ash in Miike Smelter
conveyor
by-pass duct
coking zone
hot air
settler
tuyere
smelting zone
boiler
water wall tube
Schematic Illustration of MF Furnace
The Law Concerning Special Measures Against Dioxins
Promulgated on July 16, 1999 and Enforced on January 15,
2000
A unique low in the world specialized for protection of the
environment by controlling the dioxin emissions from waste
incinerators and several industrial processes, i.e.,
Electric arc furnace (EAF) for steelmaking
Sintering plant for iron ores
Secondary zinc production from EAF dust
Secondary aluminum alloy production
In the law:
Tolerable Daily Intake (TDI) is set at 4 pg-TEQ/(kg-body・d)
Co-planar PCB is included in dioxins as well as PCDD/Fs
Countermeasures for dioxins emissions in the specified metallurgical processes
Electric arc furnace Iron ore sintering
process
Secondary Zn
production
Secondary Al
production
Dioxins emissions
In 2007
49 g-TEQ/y
20 g-TEQ/y
1.8 g-TEQ/y
13.4 g-TEQ/y
Typical conc. of waste gas
In 2000
0.03~76 ng-TEQ/Nm3
(n=60)
0.012~1.7 ng-TEQ/Nm3
(n=16)
0.55~72 ng-TEQ/Nm3
(n=8)
0.05~5.9 ng-TEQ/Nm3
(n=17)
Annual production
About 30 mil. ton/year
About 100 mil. ton/year
About 60,000 ton/year
About 1.2 mil ton/year
Major counter-measures
* Pre-removals of Cl-bearing materials * Waste gas treatments
* Control of chlorine in the secondary raw materials * Waste gas treatment
* Pretreatment of EAF dust (de-Cl, dioxins) * Waste gas treatment
* Selective removal of organic Cl * Cl-less flux *Waste gas treatment
Regulation of the emissions
Previous: 5 ng-TEQ/Nm3
New: 0.5 ng-TEQ/Nm3
Previous: 1 ng-TEQ/Nm3
New: 0.1 ng-TEQ/Nm3
Previous: 10 ng-TEQ/Nm3
New: 1 ng-TEQ/Nm3
Previous: 5 ng-TEQ/Nm3
New: 1 ng-TEQ/Nm3
OUT LINE
• Introduction
• Environmental Issues of Extractive Metallurgy
• Important role of control heavy metals in Recycling
• How to control hazardous elements for Sustainability - regulation -
• Conclusions
Legal agreements for the protection of the Carpathian-Danube region has been
signed by 11 central and eastern European countries in 2001, committing them to
develop national policies to decrease pollution in the Danube.
USA-Canada Great Lakes Water Quality Agreement (1978 )
Basel Convention on the Control of Transboundary Movements of hazardous
Wastes and their
disposal (1992)
Rotterdam Convention on the Prior Informed Consent Procedure for Certain
Hazardous
Chemicals and Pesticides in International Trade (voluntary since 1980, in force - 2004)
Stockholm Convention on POPs (2004)
UNECE Water Convention on the Protection and Use of Transboudary Waters and
International lakes (1996)
UNECE Convention on the Trans boundary effects of Industrial Accidents (2000)
Legal Agreements at International Level
Main Directives on water pollution control:
Directive on Pollution caused by discharges of certain Dangerous substances
DSC 76/464/EC with ‘daughter directives’
Water Framework Directive WFD 2000/60/EC
Directive on Integrated Pollution Prevention and Control IPPC 96/61/EC
Urban Waste Water Treatment Directive UWWTD 91/271/EC
Fish Water Directive and Shell Water Directive 78/659/EC
Bathing Water Directive 76/160/EC
Drinking Water Directive 80/778/EC
Nitrates from Agricultural Sources Directive 91/676/EC
European
Union
Legal Agreements at National Level
USA Clean Water Act (CWA) (1972, with subsequent enactments in 1981, 1987)
Established under the Basic Environment Law, are target levels for water quality that are to be
achieved and maintained in public waters, to achieve two major goals:
protection of human health
- uniform national standards applicable to all public waters
- a total of 23 substances including cadmium and total cyanide
conservation of the living environment
- met by classifying rivers, lakes, reservoirs, and coastal waters; established
for each
class on base of water usage
- established for pH, BOD, COD, DO, total coliform, SS, and nitrates and
phosphorus
to prevent eutrophication
In addition, twenty-five other items were also selected for precautionary monitoring in
water environments. In 1997, EQS for groundwater pollution were also established.
Provisional guideline values have also been set for sediments contaminated by mercury
and polychlorinated biphenyl compounds (PCBs).
Japan Environmental Quality Standards (WQS)
Item
Standard Values
cadmium
0.01 mg/liter or less
total cyanide
0.01 mg/liter or less
lead
0.01 mg/liter or less
chromium (VI)
0.05 mg/liter or less
arsenic
0.01 mg/liter or less
total mercury
0.0005 mg/liter or less
alkyl mercury
not detectable
selenium
0.01 mg/liter or less
Standard values are the annual
mean. However, the value
for total CN is the maximum
value.
Source: Environment Agency
Environmental Quality
Standards
for Human Health in Japan
Environmental Quality Standards for Soil Pollution in Japan
Substance
Target level of soil quality examined through leaching
and content tests
cadmium
0.01 mg/l in sample solution and less than 1 mg/kg in rice for agricultural land
total cyanide
not detectable in sample solution
organic
phosphorus
not detectable in sample solution
lead
0.01 mg/l or less in sample solution
chromium
(VI)
0.05 mg/l or less in sample solution
arsenic
0.01 mg/l or less in sample solution, and less than 15 mg/kg in soil for agricultural
land (paddy fields only)
total
mercury
0.0005 mg/l or less in sample solution
alkyl
mercury
not detectable in sample solution
Items related to the protection of the living environment in Japan
Living Environment Items
Permissible Limits
hydrogen ion activity (pH)
Non-marine 5-8-8.6
Marine 5.0-9.0
Biochemical Oxygen Demand (BOD)
160 mg/l
(Daily Average 120 mg/l)
Chemical Oxygen Demand (COD)
160 mg/l
(Daily Average 120 mg/l)
suspended solids (SS)
200 mg/l
(Daily Average 150 mg/l)
n-hexane extracts (mineral oil)
5 mg/l
n-hexane extracts (animal and vegetable fats)
30 mg/l
phenols
5 mg/l
Items related to the protection of the living environment in Japan
copper
3 mg/l
zinc
5 mg/l
dissolved iron
10 mg/l
dissolved manganese
10mg/l
chromium
2 mg/l
Fluorine
8 mg/l
number of coliform groups
Daily Average 3000/cm3
nitrogen
120 mg/l
(Daily Average 60 mg/l)
phosphorus
160 mg/l
(Daily Average 80 mg/l)
Item
Elusion
Standards
Content
Standards
Cd
>0.01mg/l
>150mg/kg
Pb
>0.01mg/l
>150mg/kg
Cr(6+)
>0.05mg/l
>250mg/kg
As
>0.01mg/l
>150mg/kg
Total Hg
>0.00005mg/l
>15mg/kg
Se
>0.01mg/l
>150mg/kg
Elusion Standards and Content Standards for slag in Japan
Comparison of Elusion Test
country Test method size pH S/L
ratio
mixing unit
Japan
Notification No13 Under 5mm 5.8~6.3 10 Vibration 6hrs mg/L
Notification No46 Under 2mm 5.8~6.3 10 Vibration 6hrs mg/L
Recycling law 20~50mm CO2 Sat.
4.0
10 Stirring 24 hrs mg/L
USA/Ca TCLP Under 9.5mm 2.88 or 4.93 20 Vibration hrs 18 hrs mg/L
Germany DEV S4
(DIN38414)
Under 10mm Distillation
water
10 Vibration hrs 24 hrs mg/L
France AF NOR X31-2 10 Under 4mm Distillation
water
10 Vibration 6hrs
16 hrs
mg/kg
Swiss
land
TVA No control CO2
saturation
10 Vibration hrs 24 hrs mg/L
Nether
land
Availability test
(NEN7341)
Under 125μm 7 50 Stirring 3hrs mg/kg
4 50 Stirring 3hrs
Serial batch test
(NEN7343) Under 3mm 4
20×5
times
Vibration hrs 24 hrs
X 5times
mg/L
Column test
(NEN7343) - - -
To achieve
equilibrium
mg/kg
Comparison of Elusion Test Standards (mg/l)
spices
Chile
(compliance
USA TCLP)
Notification No13 by M.EV.
landfill
marine disposal
(Inorganic
sludge)
As 5 0.3 0.01
Cr 5 - 0.2
Hg 0.2 0.005 0.005
Pb 5 0.3 0.01
Se 1 0.3 0.01
Cd 1 0.3 0.01
Ag 5 - -
Cu - - 0.14
Zn - - 0.8
Ni - - 0.12
OUT LINE
• Introduction
• Environmental Issues of Extractive Metallurgy
• Important role of control heavy metals in Recycling
• How to control hazardous elements for Sustainability - regulation -
• Conclusions
The Mercury Study Report to Congress – EPA prepared this report to
fulfill requirements of the Clean Air Act Amendments of 1990. Published in
1997, it is an eight volume assessment of the magnitude of U.S. mercury
emissions by source; the health and environmental impacts of those
emissions; and the availability and cost of control technologies.
Bibudhendra Sarkar, of The Hospital for Sick Children and the Department of
Biochemistry, University of Toronto, Toronto, Canada,
([email protected]) reviewed the global picture of arsenic
pollution and the methods of monitoring it.
Process Commercial
Operation Comments
Neutralization with lime-
calcium arsenate/arsenite
Yes
not effective at removing all arsenic from solution
residue not environmentally stable
easily carbonated by atmospheric carbon dioxide,
releasing soluble arsenic
Neutralization with lime plus
ferric iron – arsenical
ferrihydrite
Yes
removes As down to <0.1 mg/L
residue stable if molar Fe/As >4
high iron requirement
high volume, high liquor retention residue
US EPA Best Developed Available technology (BDAT)
Neutralization with lime plus
ferric plus base metals – base
metal arsenical ferrihydrite
Yes
removes As down to <0.1 mg/L
residue stable if molar Fe(+ base metals)/As >4
Pressure oxidation –
scorodite or TypeⅠ/TypeⅡ
mineral
Yes
stable arsenic mineral formed
requires polishing step for <0.1 mg/L As
minimum Fe requirements
requires autoclave
low volume, low liquor retention residue, easily filtered
Summary of Methods for Bulk Removal and Disposal of Arsenic (1)
B.Harris : Hydrometallurgy 2003 – Fifth International Conference in Honor of Professor Ian Ritchie – Volume 2 : Electrometallurgy and Environmental Hydrometallurgy Edited by C.A.Young, et.al. TMS (The Minerals, Metals & Materials Society), 2003
Process Commerci
al
Operation
Comments
Atmospheric scorodite
Pilot only
stable arsenic mineral formed
requires polishing step for <0.1 mg/L As
minimum Fe requirements
low volume, low liquor retention residue,
easily filtered
pressure vessel not required
Arsenic sulphide
Yes
residue formed is unstable at pH > 4
works best with As(Ⅲ)
elemental S formed with As(Ⅴ)
melt with S to form glass
Copper arsenate Yes specialized situations only, diminishing
market required
Arsenic trioxide Yes not environmentally stable
market required
B.Harris : Hydrometallurgy 2003 – Fifth International Conference in Honor of Professor Ian Ritchie – Volume 2 : Electrometallurgy and Environmental Hydrometallurgy Edited by C.A.Young, et.al. TMS (The Minerals, Metals & Materials Society), 2003
Summary of Methods for Bulk Removal and Disposal of Arsenic (2)
Conclusions
• Non-ferrous industry have been accepted hazardous heavy metals like As,Hg and Cd
However, Non-ferrous Industry can control Heavy metals in the process
• We need more effective processes for controlling hazardous heavy metals and new concept to use them in sustainable society.