trends of arsenic in copper raw materials and its ... · october 17, 2018 metal economics research...
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October 17, 2018
Metal Economics Research Institute, JapanNobuo YAMAZAKI
Trends of Arsenic in Copper Raw Materialsand
its Technical Countermeasure in the Copper Industry
International Seminar on Impurities in Copper Raw Materials
1. Trends and its Future Prospects of Arsenic
Grade in Copper Concentrate
2. Current Status and Future of Impurity Regulation
3. Current Status and Issues of Arsenic Removal from
Copper Raw Materials
4. Immobilization and Storage of Arsenic
5. What should we do ?
1
Contents
2
Trend of As in main copper concentrate for Japanese Smelters
It used to be beautiful conc., but not now
0.040
0.090
0.140
0.190
0.240 Escondida
0
0.05
0.1
0.15
0.2
0.25
0.3
Collahuasi
0.00
0.05
0.10
0.15
0.20
0.25
0.30 Los Pelambles
0.00
0.05
0.10
0.15
0.20
0.25
0.30
0.35
0.40
Northparks
0.1% 0.1%
0.1% 0.1%
Source: MERIJ作成
3
0.020
0.040
0.060
0.080
0.100
AsAs
25.0
27.0
29.0
31.0
33.0
35.0Cu
Cu
0.1%
30%
As & Cu Trend of Imported Copper Concentrate for Japan
As0.04➡0.09％
Cu32➡26％
As（
％）
Cu（
％）
Source: MERIJ作成
Since 1991
As/Cu Ratio
2.8 !!
4
How far will As grade of copper concentrate rise?
0.1
0.12
0.14
0.16
0.18
0.2
0.22
0.24
As（
％）
年Source: Teck-Aurubis, CESLからMERIJ作成
High As-Cu Mine Project( Planned for Development after 2021）➡ 60kt-As increase ➡ 0.09％As UP ➡ 0.31％ As in Conc
Tampakan, Marcapunta Oeste,El Galeno, La Granja, Pascua Lama, Wafi-Golpu,Canariaco Norte, Others
0.31％？
60kt-As
Chelopech, Chuquicamata, El Brocal, Toromocho, others
5
Current Status and Future of As Regulation
① Regulation of impurity acceptance of concentrate ⇒ China② Environmental regulation of air and water quality ⇒ Chile③ Regulation of marine transportation of concentrate ⇒ IMO④ Basel regulation of smelting byproduct ⇒ As, Pb grade
in copper slag?
As Hg Pb Cd F
Cu Conc 0.5% 100ppm 6.0% 0.05% 0.10%
Pb Conc 0.7% 500ppm
Zn Conc 0.6% 600ppm 0.3%
Bulk Conc 0.45% 500ppm 0.4%
① Regulation of China‘s imported concentrate acceptance (2006~ )
Source：GB20242-2006
6
➁ Comparison of actual As emission of Chilean smelting (2014) and new regulation value (The Decree N⁰28)
730
35 29.6
128
476
1735
12690 88 90 9099 99 99 99
0
100
200
300
400
500
600
700
800
Chuquicamata Paipote Chagres Altonorte
Emissions
Reguration Limit
Collection Efficiency
As Reguration Limit for CE
Source: Codelco Sustainability Report 2014
（Ｔ/Ｙ）
（Ｔ/Ｙ）
（％）
（％）
Possible for 9％ improvement？
Possible for 35% reduction？
Current Status and Future of As Regulation
51% reduction
As（ｔ/ｙ） Ratio（％）
Whole World 150,000 100
Custom Smelter 50,000 33
breakdown
Chinese Smelter 40,000 27
Outside China 10,000 6
Self Treatment 100,000 67
breakdown
De-As Roasting 24,000 16
Integrated Mine/Smelter
76,000 51
7As for China：Imported Conc17,333kdmt×As0.25%=43,000ｔ/ｙ
Arsenic Balance of Copper Conc. in the World
Source：MERIJ作成
Source：MERIJ作成
Integrated Mine & Smelter
51%
De-As Roasting
16%
Custom Smelter
33%
Destination of Arsenic
Where should Arsenic be separated / removed?
8
IntegratedSmelter
Mining/Grinding/Flotation
Removal from Conc.Direct LeachingDe-As Roasting
Removal from Intermediates
Flue DustWaste water from AcidPlantMatte, Blister, Electorolyte, Slag
Mine Smelter
SX/EW
Intermediates
Current Status and Issues of Arsenic Removal
E・Cu
E・Cu FixationImmobilization
Separation from Ore
9
Current Status and Issues of Arsenic Removal
Trigger Penalty (US$/dmt) US$/t-As
0.1％＜As＜0.5％ 3-4＄/0.1％ US$3-4K
0.5％＜As＜1.0％ 4-6＄/0.1％ US$4-6K
1.0％＜As＜5.0％ 5-8＄/0.1％ US$5-8K
5.0％＜As＜10.0％ 8-10＄/0.1％ US$8-10K
10.0％＜ 10-15＄/0.1％ US$10-15K
Source: Codelco 2015
US$4.8KUS$5.7K
US$8K
US$10KUS$10K
Where should As be separated / removed?（Mine or Smelter？）depending upon Economic and Market Condition ?
Source: ヒアリングによりMERIJ作成
$/d
mt
Converted Value to 1ton of As
As Grade
Current status and issues of As removal from Cu Conc.
10
CuConc.（16）
Hydrometallurgy（15）
Pyrometallurgy
（1）
Atomosphere（12）
Pressurization(3)
Sulfuric（5）
Chloride（4）
Alkali（3）
Roasting
POXCESLFLSmidthFerric LeachingGalvanoxPLATSOLBioCopAlbionHydro CopperINTECNikko ChlorinationSumitomo ChlorineToowongEquity SilverPoly Sulfide
POXCESLPLATSOL
FLSmidthFerric LeachingGalvanoxBioCopAlbionHydro CopperINTECNikko Chlorin.Sumitomo Chlori.ToowongEquity SilverPoly Sulfide
FLSmidthFerric LeachingGalvanoxBioCopAlbion
Hydro CopperINTECNikko Chlorin.Sumitomo Chlorn.
ToowongEquity SilverPoly Sulfide
Partial Roasting
Ministro Hales
11
4Cu₃AsS₄(s)+31O₂(g)+2Fe₂(SO₄)₃(aq）+2H₂O→12CuSO₄（aq）+4FeAsO₄・2H₂O(s)+8S⁰(s)+2H₂SO₄(aq)ConditionTemp. :150℃ Total P. :13.6atm O₂ P.: 9.5atm R.T. 60~90min.Re-ground to 10㎛ Leaching Catalyst: Chloride 12g/l
CESL Cu-As Process (Visit on Sept. 2017）
Source: CESL
12
Scorodite+BFAS
Elemental
Sulfur
30%
Scorodite
24%
Hematite15%
Pyrite8%
Silicates6%
Clay4%
Others13%
Source: CESL
Source: CESLSource:CESL
Source:CESL
Long Stability Test (TCLP)
As Limit:5ppmScorodite Phase
Silica
As Residue
SEM of As Residue
As in leachate 800days
Scorodite from CESL Process
Partial Roasting at Ministro Hales (Visit on Oct.2017)
13
Conc. Calcine
As 5% 0.3%
2HAsO₂ + 3Ca(OH)₂ → Ca₃(AsO₃)₂ + H₂O
Disposal to Monte Cristo
Top of Roaster
ESP
Calcine HopperCa/As Filtration by LAROX
2Cu₃AsS₄(s)→3Cu₂S(s)+As₂S₃(g)+S₂(g)
2As₂S₃(g)+9O₂(g)→2As₂O₃(g)+6SO₂(g)As₂O₃ + H₂O → 2HAsO₂
Work Equipment
680℃ To Chuquicamata
Roaster&Cyclone
Conc. to Roaster
14
A part of Arsenic Removal from Circuit as Ca₃(AsO₄)₂, As₂S₃, FeAsO₄Cu₃As FeOOH・AsO₄
Arsenic Removal at Copper Smelter
FSF
PSC
Anode Furnace
Boiler EP
Acid Waste Water
Gas Cooler Acid Plant
Flue Dust
Slag
Blended Cu Conc.
Gas
Gas Boiler EPSulfuric Acid
Anode
Liberated E Cu
Flue Dust
Leaching
Electrolyte
Decopperizing Tank
Slag
Slag
Floatation
Slag Conc. Iron Conc
E Cu
EvaporationNi Sulfate
Ion Exchange Tower
Sb,Bi Residue
Slime
Tank House
Arsenic Distribution
15
0
1000
2000
3000
4000
2009 2010 2011 2012 2013 2014 2015 2016
Concept of Basel regulated objects
Those containing As, Cd and Pb at 0.1 wt% or more are applicable(Appended Table 3)
Source :Ministry of Finance customs clearance statistics
Source: 環境省
Current Status and Issues on Copper Slag
セメント向
け, 56ブラスト
材, 24
土工用材
料, 13
コンクリー
ト用骨材, 7
Cement material56%
Sandblasting Material24%
ConstructionWorks Material13%
Aggregate for Concrete7%
Uses of Copper Slag
Cu Slag3,500ｔ/y(70％)
As Distributuon
Storage, others 1,280ｔ/y(30%)
Source: MERIJ作成
Transition of Export of Copper Slag from Japanese Copper SmelterKt
Table1
Table2Table3
Arsenic Fixation from Flue Dust at Ecometales
16
Capacity5,000t-As/y50,000t-Flue Dust/y70,000m³-WasteWater/y Scorodite 12%As,10%Fe
Cu30g/l
Cu9%Fe21As4%
80℃FA300g/l
As20g/lCu35g/l
ConditionsFe/As=1.280℃ RT 24hrpH0.7-1.1 at 1st
1.3-1.5 at 2nd
Source：Ecometales Homepage
Leaching of Flue Dust and Arsenic Fixation as Scorodite（Visit on October 2017 ）
Flue Dust Leaching Step Scorodite Formation Step
Immobilization & Storage of Arsenic
17
FixationImmobilization
Pyro Hydro
As₂O₃
High Purity Metal
Ca₃(AsO₃)₂ CopperArsenate
Amorphous
ScoroditeCrystalline
Ca₃(AsO₄)₂
CrystallineScorodite
Encapsulation
Scoro+HAPVitrification
Yukonite（Scoro+Ca）
HAP:Hydrated Aluminum Phosphate(AlPO₄・1.5H₂O）
Long Term Stability of Crystalline Scorodite(DOWA Process)
18
Crystalline Scorodite by DOWA
Scorodite As Fe
Scorodite TheoriticalGrade
32.4％ 24.2％
DOWA 30.9％ 24.1％
Ecometales 12％ 10％
CESL 8％
Source: DOWA Cobre 2013, Copper 2016
Immobilization & Storage of Arsenic
Source：MMIJ March 2012, Mitsune
Source: Fujita, TMS 2012
Source: Hydrometallurgy1989,Ettel
Structure plan for Storage
Difference of Crystal Size
Long Term Stability
DOWA Scorodite
Source: Copper2016,Fujita
Solubility of Scorodite
Amorphous Scorodite
NO.13 Leaching Test Result of MOE
As
Leac
hat
e(p
pm
)Quality of Scorodite
Tsumeb Smelter in Namibia & Ecometales in Chile
19
Source: Google Earth
Source: Google Earth
Source: CEE bank watch Network
Source: Ecometales Homepage
Examples of Current Status and Issues for Arsenic Storage
Storage
Landfill Area
As Residue
Landfill AreaEcometales
Tsumeb Smelter
What Should We Do?
20
Joint Arsenic Treatment Company
Storage for Scorodite
KOSAKA
HIBI/TAMANO
TOYO
NAOSHIMA
SAGANOSEKI
ONAHAMA
1. Secure international competitiveness 2. Improvement of raw materials treatment
capability 3. Improvement of environmental conservation
①Unified Management at Joint Arsenic Treatment Company in Japan
What Should We Do?
21
Europe China Japan Chile/Peru
Crystalline ScoroditeProduction Plant
International Inspection System for Arsenic
Toward Unified Management For Arsenic
② International Approach to Preventing Arsenic Diffusion
