metal recycling technology from secondary and waste … · 2015. the proportion of ... － focus on...

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M2R2

Metal Recycling Technology From

Secondary And Waste Materials

Wang Haibei

BGRIMM – Xuzhou Institute

April 2012

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M2R2

Contents

1. Introduction

2. About BGRIMM – Xuzhou Institute

3. Copper

4. Zinc

5. Nickel and Cobalt

6. Precious Metals

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M2R2

－ China is the biggest metal output and consumption country;

－ The output of non-ferrous metal is about 34.2 million tons in

2011;

－ But the ratio of metal recycling is much lower than the

developed countries such as USA, Japan and Europe

－ The ratio of main non-ferrous metal recycling is more than

60%, even 98% in the developed countries

－ In China the ratio of Cu, Al, Pb, Zn is only 30%, 32%, 34%

and 2.8%

Introduction

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Resource

Energy HOW TO

Environment

Introduction

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Introduction

Raw materials Economy development Population increase

Life products

Spent products

Metal recycling

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Introduction

Metal recycling can:

－ Reduce mine exploitation and keep the balance of supply

and consumption

The output by metal recycling is willing to 15 million tons in

2015. The proportion of recycling Cu, Al, Pb will reach 40%,

30% and 40%.

－ Reduce energy consumption distinctly. Compared with

prodction from mine, energy consumption with recycling is

only 18% for copper, 28% for lead, 38% for zinc, 11%.

Introduction

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Introduction

Metal recycling can:

－ Low environmental pollution, low

capital and operation cost

Compared with production from mine:

Capital cost: 20-30%

Operation cost: 15-40%

Environmental pollution:

Pb 9%, Al 50%, Cu 42%

Introduction

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－ Founded in 1978

－ State own company and sub-institute of BGRIMM

－ Specialty for non-ferrous metal recycling

－ Focus on research, engineering, rare and precious metal

production, hydrometallurgy and environmental equipment

ment manufacture

About BGRIMM-Xuzhou Institute

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－ Pretreatment technology

－ Smelting and leaching technology

－ Extraction technology such as SX, ion exchange

－ Purified production


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Main production

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Specialty for hydrometallurgy

and environmental equipment

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Copper scrap recycling

－ The output of secondary copper is about 30% of the total

production of electrowinning copper in China

－ 38% copper scrap directly made copper prodution

－ 12% copper scrap went into concentrate smelter

－ 50% went into special copper scrap recycling plant

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Reverberator furnace:

• Flexible for material, from 30-90% copper grade

• Scale: 50-350t/d

• Low capital cost

• High energy consumption

• High operation cost

• Directly produce copper rod or cathode copper

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Blasting furnace:

• Treatment: low grade copper scrap

• Low capital cost

• Rare and precious metal recovery

• High energy consumption

• Need fire refining and electrolysis to produce cathode

copper

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FRHC process:

• Introduced from La Farga Lacambra in Spain

• Treatment: >92% copper grade

• Production: copper rod

• High efficiency

• Copper grade: >99.93%, impurities<50ppm

• Conductivity: 100.4-100.9% IACS

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Other processes:

• Kaldo process

• ISA/AUSMELT process

Development:

• Low grade copper scrap treatment technology

• Direct electrolysis for copper scrap

• Rare and precious metal recovery

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Zinc recycling

• More than 60% zinc is used in steel industry

• Zinc reclycing mainly from steel plant dust

• Now the output of secondary zinc in China is only 120kt,

accounting for 2.8% of total production

• The final production is zinc ingot

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Zinc recycling

Zinc dust in steel plant:

• Blast furnace dust, 0.1-3.0% Zn

• Converting furnace dust, 0.1-3.5% Zn

• Converting furnace OG mud, 0.5-3.5% Zn

• Electrical furnace dust, 1-30%

• The rest composition in dust is iron

• Containing nickel and chromium in EF dust

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Zinc recycling

Technology for dust treatment:

• Zinc<1% dust: Return to pelletizing and sintering

• Zinc<5% dust: Magnetic and gravity flotation

• Zinc>5% dust: Walez process

RHF process

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Zinc recycling

Walez process:

• Zinc dust: Zn 5-30%, Fe 20-40%, Pb 1%, In 0.0054%, C

10-35%, S 0.5-1%, Cl 0.1-2.5%

• Zn, Pb, In, In and Ag are reducted and go to rotary kiln

ash

• Iron and part of carbon still in the slag and can be

recoveried by flotation.

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Zinc recycling

• Temperature: 1200-1250C

• Time: 2.0h

• Zinc recovery rate >90%, zinc in slag less than 1%

• Zinc ash: Zn 55-60%, Pb 8-10%, In 0.05%, Fe <2.5%,

C<1%, Ag>600g/t

• Iron concentrate: Fe>65%, iron recovery 70%

• Carbon>70%, return to rotary kiln for reduction

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Zinc recycling

RHF process:

• BGRIMM – Xuzhou Institute is developing RHF process

to treat nickel laterite and zinc dust from steel plant

• Nickel laterite and zinc dust mixed together

• The productions are zinc oxide and ferronickel

• Most metals become useful in the process

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Zinc recycling

RHF flowsheet

Zinc dust and nickel laterite

Agglomeration

RHF

Gas slag

Dust collection Go to EF or flotation to produce ferronickel

Zinc oxide

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Zinc recycling

The test result indicated:

• Zn/Pb/In/Ag went to gas collected as zinc dust

• Recovery: Zn>90%, Pb>85%, In>80%, Ag>95%

• Ni/Fe/Cr went to metallic phase as ferronickel

• RHF slag could go to EF to produce ferronickel

• RHF slag also could produce ferronickel by gravity and

magnetic flotation

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Secondary nickel and cobalt resource:

• High melting point alloy

• Chrome nickel alloy

• Spent hard alloy

• Ni/Co catalyst

• Magnetic material

• Used lithium battery

Nickel and cobalt recycling

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High melting point alloy:

• Electrolysis and electrochemistry process

-- For high grade nickel alloy

-- Alloy was melt and cast to anode by electrical furnace

-- Nickel was dissolved from anode selectively and produce

metal in cathode

-- Cobalt and other metals recovery from electrolyte


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• L – SX process

-- For low grade nickel and cobalt alloy

-- Alloy was pretreated by crushing and grinding

-- The powder was leached to solve valuable metals

-- Precipitation or N235 SX to remove iron

-- P204 SX for impurities removal

-- P507 SX for nickel and cobalt separation

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Ni & Co alloy

Crushing and grinding

Leaching

Solvent Extraction

Organic phase Aqueous phase

Stripping Thickening and crystallization

CoCl2 solution NiSO46H2O

Crystallization

CoCl26H2O

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Hard alloy:

• Sodium roasting process

-- Alloy, oxidant and NaNO3 mixed together to roast

-- Water leaching to dissolve tungsten as Na2WO4

-- After purification solution produce APT etc

-- Recovery cobalt and other metals from leaching residue


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• Electrochemistry dissolve process

-- Cobalt dissolved by electrochemistry

-- Cobalt was extracted from solution

-- The rest WC modified composition by carbonizing

furnace

-- Reduce oxygen and increase carbon in furnace

-- Recovery: WC>98%, Co 92-95%


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Sodium roast Zinc melting Electrochemistry dissolve

Metal recovery W>90%, Co>90% W>95%, Co>95% W 95-96%, Co 92-95%

kWh/t alloy 1400 6000-10000 300

Environment NO2 pollution Friendly Friendly

Equipment Much, simple Much, complex Simple

Energy efficiency / 20-30% Current efficiency>90%

Capital cost High High Low

Reagent

consumption

High Low Middle

Operation cost >10,000RMB 11,000RMB 5,000-6,000RMB

Profit(RMB/t alloy) / 10,000RMB 15,000RMB

Labor More Less Less

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Spent lithium battery:


Spent lithium battery

Reductive roasting

Leaching

Solution Residue

Copper SX Copper production

P204 for impurities removal

P507 for nickel and cobalt separation

Cobalt production Nickel production

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Ni/Co/Mo/V catalyst:

• Sodium roasting process

-- BGRIMM – Xuzhou Institute developed the process

-- Sodium roast to remove organic, sulphur and carbon

Aluminium and molybdenum convert into sodium salt

-- Water leaching to solve Al and Mo

-- Nickel and cobalt extraction from residue by acid leaching


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Sodium roast

Milling

Gas Absorb tower

Water leaching

L/S

Solution(Mo/V/Al) (NH4)2SO4

Spent catalyst

L/S

Al(OH)3 Al2O3 Calcine L/S

Mother liqor

Acid leaching Ni/Co residue

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NH4VO3 Calcine V2O5

L/S

Mother liqor

(NH4)2MO4

Recovery: Ni>95%,

Co>95%, Mo>96%,

V>93%, Al>99%

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• Reductive smelting process

-- BGRIMM – Xuzhou Institute carried out tests for

reductive smelting process

-- Spent catalyst and pyrite mixed together for smelting

-- At 950-1000C Ni/Co/V/Mo converted into sulphide

separated from carrier and slag

-- Polymetallic sulphide is treated by pressure leaching or

oxidative leaching


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Precious metal catalyst:

• BGRIMM – Xuzhou Institute developed smelting process

to treat low grade and refractory precious materials

• For unitary precious catalyst it is solved for extraction

• For high grade precious catalyst it can leach directly

• Low grade and refractory precious materials need to

enrich precious metals

Precious metal recycling

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Precious metal recycling

Spent precious metal catalyst

EF smelting

Enrichment Slag

Leaching

Solution Residue

Ion exchange

Pt/Pd/Rh production

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• Metal recycling should be treated with concentrate smelter

by advanced technology

• Valuable metal recovery should be considered in recycling

• Advanced technology for low grade secondary resource

should be developed

• Gathering channel and policy for secondary resources

need to improve

Conclusion

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谢谢！

结束语

metal recycling technology from secondary and waste … · 2015. the proportion of ... － focus on...

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