Practical Sourcebook on Mercury Storage and Disposal_Revised Draft

8/11/2019 Practical Sourcebook on Mercury Storage and Disposal_Revised Draft

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Praccal Sourcebook on

Mercury Storage and Disposal

Revised Dra (15.08.2014)


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TABLE OF CONTENTS

INTRODUCTION: ABOUT THE SOURCEBOOK p. 1

OVERVIEW: TOWARDS ENVIRONMENTALLY SOUND STORAGE AND DISPOSAL OF MERCURY p. 2

1. TYPES AND SOURCES OF MERCURY WASTES p. 3

1.1. Sources of mercury supply p. 3

1.2. Excess mercury p. 4

1.3. Types of mercury waste p. 4

1.4. Sources of wastes consisng of mercury or mercury compounds p. 5

1.5. Sources of wastes containing mercury or mercury compounds p. 6

1.6. Sources of wastes contaminated with mercury or mercury compounds p. 6

2. ENVIRONMENTALLY SOUND MANAGEMENT OF MERCURY WASTES p. 7

2.1. Government or private stocks and primary mining p. 8

2.2. Spent mercury-added products p. 8

2.2.1.Dental amalgam p. 10

2.3. Point sources of emissions and releases p. 10

2.3.1.Mercury capture in non-ferrous-metals p. 12

2.4. Manufacturing processes in which mercury or mercury compounds are used p. 13

2.4.1.Decommissioning of mercury cell chlor-alkali facilies p. 14

3. TEMPORARY STORAGE, PACKAGING, TRANSPORT AND TRACEABILITY p. 15

3.1. Temporary storage p. 15

3.2. Packaging, transport, and traceability p. 17

4. TREATMENT p. 19

4.1. Recovery/recycling and extracon processes p. 19

4.2. Management of residues, emissions and releases during treatment p. 21

5. DISPOSAL OPTIONS p. 22

5.1. Stabilizaon/solidicaon p. 22

5.2. Long-term storage/aboveground warehouse storage p. 24

5.3. Specially engineered landll p. 26

5.4. Underground disposal p. 28

5.5. Export for environmentally sound disposal p. 30

5.6. Choosing disposal opons p. 32

GLOSSARY, ACRONYMS AND ABBREVIATIONS p. 33

REFERENCES p. 37


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LIST OF BOXES

Box 1 Wastes consisng of mercury or mercury compounds p. 5

Box 2 Wastes containing mercury or mercury compounds p. 5

Box 3 Wastes contaminated with mercury or mercury compounds p. 5

Box 4 Essenal principles for the ESM of mercury wastes p. 7

Box 5 The eect of mercury control technology on output pathways p. 12

Box 6 Treatment of NFM ores and sludge contmainated with mercury in Japan p. 12

Box 7 Soil washing at a former waste processing and recycling facility p. 13

Box 8 Temporary storage of mercury-added products in the San Lazaro Hospital p. 15

Box 9 Temporary storage of mercury contaminated sludge on-site at a NFM plant p. 16

Box 10 Temporary storage in Las Caevas by Minas de Almaden (MAYASA) p. 16

Box 11 Mercury asks and receptacle p. 17

Box 12 Plasc drum p. 17

Box 13 Steel barrel p. 17

Box 14 Transport of wastes consisng of mercury (US) p. 18

Box 15 Acceptance control p. 18

Box 16 The signicance of traceability p. 18

Box 17 Rotary kiln p. 20

Box 18

The end-

cut/air-

push recycling process for linear uorescent lamps

p. 20

Box 19 Recycling of mercury-added baeries via the Sumitomo process p. 21

Box 20 Wastewater and gas treatment p. 21

Box 21 Stabilizaon p. 22

Box 22 Solidicaon p. 22

Box 23 Sulphur stabilizaon of elemental mercury p. 22

Box 24 Stabilizaon and microencapsulaon of mercury wastes in a sulphur polymeric matrix p. 23

Box 25

The challenges associated with the long-term storage of stabilized mercury wastes

p. 23

Box 26 US aboveground warehouse storage p. 24

Box 27 Specially Engineered landll p. 27

Box 28 Prototype container potenally suited for permanent storage p. 28

Box 29 Underground disposal in salt mines (Germany) p. 29

Box 30 Export of mercury waste under the Basel Convenon p. 30

Box 31 Export of catalysts contaminated with mercury (Indonesia) p. 30

Box 32 Export of mercury-added uorescent lamps for recycling (Philippines) p. 31

Box 33 Export of by-product mercury from a gold mine for stabilizaon and disposal (Peru) p. 32


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LIST OF FIGURES

Figure 1 Overview: Towards environmentally sound storage and disposal of mercury p. 2

Figure 2 Potenal sources of mercury supply p. 3

Figure 3 Excess mercury: Origin and development p. 4

Figure 4: Sources of wastes consisng of mercury or mercury compounds p. 5

Figure 5 Sources of wastes containing mercury or mercury compounds p. 6

Figure 6 Sources of wastes contaminated with mercury or mercury compounds p. 6

Figure 7 ESM of wastes consisng of mercury or mercury compounds p. 7

Figure 8 ESM of mercury-added products p. 8

Figure 9 ESM of amalgam and dental amalgam wastes p. 10

Figure 10 ESM of point sources of emissions of mercury and mercury compounds p. 11

Figure 11 Process ow and fate of mercury in NFM processing p. 12

Figure 12 ESM in manufacturing processes using mercury or mercury compounds p. 13

Figure 13 Preparaon for permanent storage of metallic mercury and site remediaon p. 14

Figure 14 Basic steps in the recovery/recycling and treatment of mercury wastes p. 19

Figure 15 Potenal eects and benets of S/S p. 22

Figure 16 Disposal opons for stabilized/solidied mercury wastes p. 23

Figure 17 Eligibility of mercury wastes for disposal in a SEL p. 26

Figure 18

Eligibility of mercury wastes for disposal in a SEL

p. 26

Figure 19 Eligibility of mercury wastes for underground disposal p. 27

LIST OF TABLES

Table 1 Challenges and opportunies associated with aboveground warehouse storage p. 25

Table 2 Eligibility criteria for landll disposal in the EU and the US p. 26

Table 3 Challenges and opportunies associated with storing mercury wastes in SELs p. 27

Table 4

Challenges and opportunies associated with the permanent storage underground of mercuryp. 29


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Introducon: About the Sourcebook

What is the audience?

The main target audience of the Praccal Sourcebook on Mercury Storage and Disposal are policy and decision -

makers involved in the management of mercury waste, parcularly in developing countries and countries with

economies in transion. Meanwhile, the Sourcebook may also serve as a useful reference for other stakeholdersinvolved in the management of mercury wastes, including from non-governmental organizaons, industry, and civil

society.

What is the purpose?

The overall objecve is to enhance the capacity of governments and other relevant stakeholders to store and

dispose mercury wastes in an environmentally sound manner. The Sourcebook aims to do so by providing

informaon on the opons and technologies that are available as well as by highlighng important policy and legal

consideraons. This document is envisaged to address praccal quesons such as: What kind of mercury wastes

exist? Where are they generated? How can mercury wastes be treated, recovered and recycled? Which opons areavailable for the temporary storage and (nal) disposal of mercury wastes? The Sourcebook synthesizes exisng

knowledge in the eld of temporary storage and (nal) disposal to provide answers to these quesons. In doing so ,

the Sourcebook will allow relevant stakeholders to make informed choices and ensure the environmentally sound

management of mercury wastes. In doing so, the Sourcebook also aims to assist in the (early) implementaon of

the Minamata Convenon on Mercury, in parcular Arcle 11 on mercury wastes.

What is the format?

The Sourcebook is a praccal introducon to mercury storage and disposal. It is not a detailed technical guidance.

Other sources, such as the Basel Convenons technical guidelines for the environmentally sound management of

mercury wastes are available for this purpose and are cross-referenced in this document. The Sourcebook can thus

be seen as an entry point.

What is the scope?

The focus is on the storage and disposal of mercury wastes. However, storage and disposal cannot be understood

in isolaon. Rather, it is necessary to take a holisc approach towards mercury waste management. To the extent

possible, the Sourcebook therefore also discusses the types and sources of mercury wastes, mercury capture,

separaon and collecon, handling and transport, recovery and recycling, and treatment.

Which aspects are not covered?

The Sourcebook does not go into detail regarding the waste prevenon dimension. The queson of mercury -free

alternaves and similar issues are not discussed.

What is the relaonship with other documents and processes?

As a project of the Global Mercury Partnership, the Sourcebook builds upon the waste management, storage and

disposal projects implemented in the respecve Partnership areas as well as the studies, guidance and informaon

materials disseminated by the Partnership. The Sourcebook aims to operaonalize exisng technical guidance

documents, such as the Basel Technical Guidelines on the environmentally sound management of mercury wastes.

1


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Figure 1: Overview: Towards environmentally sound storage and disposal of mercury

Make an inventory

Sources of mercury supplySources of wastes containing or contaminated

with mercury or mercury compounds

Mercury or mercury

compounds

Waste?

Wastes consisng of mercury

or mercury compounds

Wastes containing or contaminated with

mercury or mercury compoundsCommodity mercury

Interim storage

Manage in an environmentally sound manner

Yes

No

Sell or export for

an allowed use

Long-term storage/

aboveground

warehouse storage

Specially

engineered landll

Stabilizaon/

solidicaon

Underground

disposal

Export

Extract?

Yes

No

Go to mercury

or mercury

compounds

Eligible for

disposal?

YesNo

Temporary storage

Extracon

Yes

Temporary storage

Chapter 1

Chapter 2

Chapter 3

Chapter 4

Chapter 5

2

Overview: Towards environmentally sound storage and disposal of mercury wastes


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Chapter 1: Types and Sources of Mercury Wastes

In order to gain a full understanding of the storage and disposal of mercury wastes, it is necessary to understand

what types of mercury wastes exist and where they come from. Since waste consisng of mercury is mercury that

has been classied as waste, the sources of mercury supply will be discussed rst. As an inial step, It is

recommended for governments to make an inventory. The inventory will allow targeted acon and form the basis

of measures to be taken subsequently. Data should be gathered on the following:

i) Mercury supply and demand ows (including trade)

ii) Mercury emissions and releases

iii) Types, volumes and fate of mercury wastes as well as their owners/generators

iv) Present and future stocks of excess mercury

In order to assist governments and stakeholders, UNEP developed the Toolkit for idencaon and quancaon

of mercury releases, available at: hp://www.unep.org/chemicalsandwaste/Mercury/MercuryPublicaons/

GuidanceTrainingMaterialToolkits/MercuryToolkit/tabid/4566/language/en-US/Default.aspx. (ref. 1)

Under the Minamata Convenon, Pares shall endeavour to idenfy sources

of mercury supplygenerang stocks exceeding 10 metric tons per year that

are located within its territory (Arcle 3 paragraph 5 (a)). (ref. 2)

There are several potenal sources of mercury supply (see gure 2):

Mercury may become available from manufacturing processes in which

mercury and mercury compounds are used, be recovered from end-of-life

mercury-added products or wastes contaminated with mercury, or be

Excess mercury from

manufacturing processes inwhich mercury or mercury

compounds are used

Primary mercury mining

Mercury and mercury

compounds from industrialprocesses with mercury

impuries in the raw material

Government or private stocks

Mercury recovered from

wastes containing or

contaminated with mercury

Figure 2: Potenal sources of mercury supply (compiled based on refs. 3, 4)

Mercury supply

It should be noted that some of these sources may generate mercury compounds, rather than elemental mercury.

In such cases, the compounds may have to be treated in order to recover the elemental mercury. Further,

elemental mercury may need to be puried, whether for future use or disposal

With the switch to more ecient and environmentally sound alternaves and the restricons on uses imposed by

naonal law or the Minamata Convenon, demand for mercury is decreasing. Supply from some sources will also

cease: Under the Minamata Convenon, mercury from the decommissioning of mercury cell chlor alkali facilies

may only be used to meet demand within the sector; any excess must be disposed of in an environmentally sound

manner (ESM) (Arcle 3 paragraph 5 (b)). Primary mercury mining is to be phased out within 15 years of the

1.1. Sources of

mercury supply

recovered during the processing of raw materials with mercury impuries (such as non -ferrous metals (NFM) (e.g.

zinc) or natural gas). Exisng stocks and mercury from primary mining are further potenal sources. (refs. 3, 4)

Potenal sources of mercury and mercury compounds


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Naonal/regional/

global supply

Figure 3: Excess mercury: Origin and development (adapted from refs. 9, 10)

Excess = necessary

storage/disposal

capacity

Naonal/regional/

global demand

Development over me

Excess (or surplus) mercury is the amount of naonal, regional or global

mercury supply that exceeds naonal, regional or global demand for use in

products and processes (see gure 3). (refs. 8, 9, 10)

The amount of excess mercury will determine the capacity needed for

environmentally sound storage/disposal (refs. 8, 9, 10). As mercury is a

naturally occuring element, it cannot be destroyed. When it is excess, it must

be stored safely or transformed to a form with minimal mobility, and reliably

sequestered from the environment. Sucient capacies for treatment, storage and disposal should therefore be in

place. It has been esmated that 30,000-50,000 tons of excess mercury will become available globally by 2050

(refs. 5, 6, 7, 11, 12).

1.2. Excess mercury

1.3. Types of

mercury wastes

The Basel Convenons Technical Guidelines for the environmentally sound

management of wastes consisng of elemental mercury and wastes

containing or contaminated with mercury and the Minamata Convenon on

Mercury idenfy three categories of mercury wastes: Wastes consisng of

mercury or mercury compounds, wastes containing mercury or mercury

compounds and wastes contaminated with mercury or mercury

compounds (see boxes 1, 2 and 3). (ref. 13)

It should be noted that wastes contaminated with mercury and wastes containing mercury mainly dier in their

origin, not necessarily in their mercury content. Normally, one would expect that wastes containing mercury has a

higher mercury concentraon than waste contaminated with mercury, however, counterexamples exist. Further

informaon on the various types of mercury wastes is available in the Basel Technical Guidelines.

4

Convenons entry into force for the party in queson (Arcle 3 paragraph 4). Meanwhile, several of the sources

listed above will connue to be a source of mercury. Excess mercury may therefore become available. (refs. 5, 6, 7)

Excess mercury: Origin and development


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Wastes consisng of

mercury or mercury

compounds

Include elemental mercury and mercury compounds recovered

from waste containing or contaminated with mercury as well as

surplus stock of elemental mercury and mercury compounds

designated as waste.

Box 3: Wastes contaminated with mercury or mercury compounds (ref. 14)

5

Box 2: Wastes containing mercury or mercury compounds (ref. 14)

Box 1: Wastes consisng of mercury or mercury compounds (ref. 14)

In order for a waste to classify as mercury waste for the purpose of the Minamata Convenon (Arcle 11),it must:

i) Contain mercury or mercury compounds in a quanty above the relevant thresholds to be dened by the

Conference of the Pares (COP) of the Minamata Convenon, and

ii) be disposed of, intended to be disposed of or required to be disposed of by the provisions of naonal law or

the Minamata Convenon.

Mercury and mercury compounds are supplied from the sources listed on page

3. They can either be:

i) classied as commodity for a use allowed under naonal law and the

Minamata Convenon (manufacturing of mercury-added products in acc.

with Arcle 4 or in manufacturing processes in acc. with Arcle 5), or

ii) classied as waste and managed in an environmentally sound manner

(ESM) in accordance with naonal law and Arcle 11 of the Minamata

Convenon (see gure 4).

This decision may be determined by the (non-)existence and scale of excess mercury supply, the infrastructure

available for the management of mercury wastes, cost calculaons, relevant internaonal rules and obligaons,and other consideraons. It is recommended for governments to establish clear rules regarding the classicaon of

mercury as waste or commodity. Countries may, for instance, decide, consistent with internaonal laws and

obligaons, that mercury from specic sources is not allowed to enter the market.

1.4. Sources of

wastes consisng of

mercury or mercury

compounds

Mercury

supply

Waste?

Wastes consisng of mercury

or mercury compounds

Mercury other than waste

mercuryNo

Yes ESM

Allowed uses

Figure 4: Sources of wastes consisng of mercury or mercury compounds

Wastes containingmercury or mercury

compounds

Include wastes of mercury-added products that easily release

mercury into the environment when they are broken, wastes of

other mercury-added products and stabilized or solidied wastes

containing mercury

Wastes contaminated

with mercury or

mercury compounds

Include residues generated from mining processes, industrial

processes, or waste treatment processes. Examples are debris and

contaminated soil, mercury loaded acvated carbon, sludges,

tailings, and waste rock

Picture: Sludge contaminated with mercury

(Courtesy: Kummel Consulng AB)

Sources of wastes consisng of mercury or mercury compounds


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Extracon and use offuels/energy sources

(e.g. natural gas)

Primary and

secondary metal

producon (e.g. zinc)

Crematoria and

cemetaries

Primary mercury

mining

Waste (co-) incineraon,

landlling, and

wastewater treatment

Producon processeswith mercury impuries

(e.g. cement)

Intenonal use ofmercury in industrial

producon (e.g. VCM)

Arsanal and small-

scale gold mining

(ASGM)

6

Stabilized/solidied

mercury

Waste containing mercury and

mercury compounds

Potenal sources of wastes containing mercury or mercury compounds

Some measuring devices

(e.g. thermometers,

sphygmomanometers)

Some switches and

relays

Some types of

lamps

Mercury-added

baeries

Some pescides

and biocides

Some cosmecs

(e.g. skin creams)

Dental amalgam

Figure 5: Sources of wastes containing mercury or mercury compounds (compiled based on ref. 13)

Figure 6: Sources of wastes contaminated with mercury or mercury compounds (compiled based on refs. 1, 13)

Waste containing mercury and

mercury compounds

Potenal sources of wastes contaminated with mercury or mercury compounds

Wastes containing mercury or mercury compounds mainly come in the form

of end-of-life mercury-added products and applicaons, but also include

stabilized/solidied mercury (see gure 5). (refs. 9, 13)

It should be noted that this list is not exhausve. For further informaon ,

see: hp://www.epa.gov/mercury/consumer.htm or hp://www.epa.gov/

mercury/consumer.htm (refs. 15, 16)

1.5. Sources of

wastes containing

mercury or mercury

compounds

Wastes contaminated with mercury are mainly generated via industrial

processes with mercury impuries (e.g. natural gas) and industrialprocesses with intenonal use of mercury (e.g. vinyl chloride monomer

(VCM)) (see gure 6). (refs. 1, 13)

Some sources (e.g. primary mining or chlor-alkali) may generate both

wastes consisng of elemental mercury and wastes contaminated with

mercury.

1.6. Sources of wastes

contaminated with

mercury or mercury

compounds


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Chapter 2: Environmentally Sound Management of Mercury Wastes

This Chapter illustrates the basic opons that are available to ensure the environmentally sound storage and

disposal of mercury wastes for important source categories.

The Basel Convenon denes ESM as taking all praccable steps to ensure that hazardous wastes or other

wastes are managed in a manner which will protect human health and the environment against the adverse

eects which may result from such wastes(Arcle 2 paragraph 8). (ref. 17)

As basic principles of ESM, mercury wastes:

should not be mixed with other wastes (where regulaon prescribes the recovery of mercury above a

certain threshold, some may be movated to circumvent such regulaon by dilung the waste);

should not be discarded in uncontrolled landlls; and

should not be (co-)incineratedwithout dedicated ue gas controls. (refs. 13, 18)

Box 4: Essenal principles for the ESM of mercury wastes

ESM of mercury wastes under the Minamata Convenon:

Under the Minamata Convenon, all types of mercury wastes must be managed in an ESM (Arcle 11), taking into

account the guidelines developed under the Basel Convenon and in accordance with requirements that the

Conference of the Pares (COP) of the Minamata Convenon will adopt. The Party then has three opons:

i) Recover, recycle, reclaim or directly re-use the waste for a use allowedto a Party under the Convenon;

ii) treat and dispose of the mercury waste in an ESM; or

iii) export the waste for mercury recovery and reuse or for environmentally sound treatment and disposal in

conformity with the Basel Convenon (for Pares to the Basel Convenon) or aer taking into accountrelevant internaonal rules, standards, and guidelines (where the Basel Convenon does not apply).

Countries should carefully consider these alternave approaches to mercury waste management in light of the

types and amounts of mercury waste they generate, and their praccal capacity to manage it in an

environmentally sound manner. Many countries may not have adequately controlled mercury retort/recovery

units, stabilizaon treatment capacity that reects the latest science, or specially engineered landlls for treated

waste nal disposal. Where these resources are absent or limited, export for ESM management to countries with

such capabilies should be considered, to avoid site contaminaon and possible exposures resulng from

inadequate handling.

The selecon of management opons discussed for specic waste streams in this chapter is, among others,

dependent on the following variables:

Countries vary in their capabilies and capacity to manage their mercury wastes. Those without adequate

capacity may need to idenfy countries capable of ensuring ESM and export their mercury wastes.

Dierent types of mercury waste may require dierent management. For example, in most cases, liquid

wastes (including elemental mercury) must be stabilized/solidied prior to disposal

Technical feasibility of recovering waste constuents and availability and costs of the process

The value of/whether there is a market for the recoverable components (including mercury)

Concentraon of mercury in the waste: A level may be set above which mercury waste should undergo

recovery. For some wastes, the concentraon may be too low to allow cost-eecve extracon.


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2.1. Government or

private stocks and

primary mining

If government or private stocks of mercury and mercury from primary

mining is classied as waste, it becomes waste consisng of mercury. The

temporary storage of such wastes should be done in an environmentally

sound manner (see p. 15).

The following opons are then available to ensure environmentally sound

storage and disposal (gure 7):

i) Long-term storage in aboveground facilies (see p. 24) unl treatment technologies and/or disposal

opons are available. The wastes should be of very high purity. The waste is thus removed from the market,

but not from the biopsphere.

ii) Disposal in specially engineered landlls (SELs) (see p. 26) or underground facilies (see p. 28) following

prior stabilizaon/solidicaon (S/S) (see p. 22). This nal disposal removes the waste from the biosphere.

S/S processes may be available only in some countries.

ii) Export for environmentally sound disposal(see p. 30) is recommended if treatment processes and disposal

opons are not domescally available. Export must be followed by i) or ii). The imporng country must have

the infrastructure to guarantee ESM and permit the import according to its naonal legislaon.

Removal from the

market

Removal from the

biosphere

Treatment

S/S

Wastes

consisng of

mercury

Underground

disposal

Specially

engineered landll

Temporary

storage

Aboveground

warehouse

storage

Export for

environmentally

sound disposal

Primary mercury

mining

Government or

private stocks

Figure 7: ESM of wastes consisng of mercury or mercury compounds (adapted and compiled from refs. 9, 13, 18, 19, 20)

A crical step in the management of spent mercury-added products is

collecon and separaon. Without adequate collecon and separaon

schemes, most of the mercury-added products will end up with the

municipal waste and might be incinerated without adequate emission

controlsor dumped in uncontrolled landlls.

It is recommended for consumers and waste generators to store spent

mercury-added products only for a limited me, as allowed by naonal

2.2. Spent mercury-

added products

Standards (ref. 13).The following opons are available to ensure ESM of spent mercury-added products:

i) Recovery/recycling (see p. 19): Mercury-added products can be recycled in facilies which oen use

specialized processes depending on the specic product. The various components are separated and

decontaminated (for instance glass, phosphor powder and metals in the case of uorescent lamps) and the

mercury extracted. Recovered mercury may be re-used for allowed uses or should otherwise be disposed of

in an ESM.

8


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ii) Export for recovery/recycling: This opon is recommended for countries where recycling technologies are

not (yet) domescally available.

For spent mercury-added products, landll disposal without prior treatment is not recommended, as mercury can

easily be released into the environment. Stabilizaon/solidicaon is also not recommended because it

signicantly increases the waste volume and does not allow the possibility of re-using valuable components. Figure

8 illustrates the steps towards the ESM of spent mercury-added products. (refs. 3, 18, 22, 23, 24, 25, 26)

It is recommended to implement approaches such as Extended Producer Responsibility (EPR) in order to recover

the costs for the ESM of mercury-added products. EPR is an environmental policy approach in which a producers

responsibility for a product is extended to the post-consumer stage of a products life cycle.

Recovered mercury

See gure 4 on p. 5

Residues contaminated

with mercuryMercury-free materials

Re-useSee gure 10 on p. 11

Spent mercury-added products from large-scale

generators (e.g. hospitals, schools, supermarkets)

Spent mercury-added products from small-scale

generators (e.g. households, small businesses)

Collecon at:

i)Drop-o depots

ii)Public places or shops

iii)Households by collectors

Environmentally

sound

temporary

storage on-site

Export for recovery/

recycling

Transport to centralized facility for

collecon and temporary storage

pending recovery/recycling

Recovery/recycling

Landll disposal

without treatment

Uncontrolled disposal in

muniipal waste

Figure 8: ESM of mercury-added products (compiled based on (refs. 13, 18, 22, 23, 24, 25, 26, 27, 28)

9

Further informaon, including on collecon schemes, is available in the Basel Technical Guidelines. For a number of

examples on eecve collecon schemes, consult the Good Pracces for Management of Mercury Releases from

Waste, available at: hp://www.unep.org/chemicalsandwaste/Portals/9/Mercury/Documents/INC2/

Good_pracces_Oct2010.pdf (ref. 27). For informaon on the management of mercury-added lamps, see

Achieving the Global Transion to Energy Ecient Lighng Toolkit, available at: hp://www.enlighten-

iniave.org/ (ref. 28).
http://www.unep.org/chemicalsandwaste/Portals/9/Mercury/Documents/INC2/Good_practices_Oct2010.pdfhttp://www.unep.org/chemicalsandwaste/Portals/9/Mercury/Documents/INC2/Good_practices_Oct2010.pdfhttp://www.unep.org/chemicalsandwaste/Portals/9/Mercury/Documents/INC2/Good_practices_Oct2010.pdfhttp://www.unep.org/chemicalsandwaste/Portals/9/Mercury/Documents/INC2/Good_practices_Oct2010.pdf


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Globally, approximately 300 tons of mercury are released into the

environment from dental amalgam every year (ref. 29), among others due to

the unsound disposal of removed llings. Dental amalgam can instead be

recycled(see Figure 9). This is economically benecial, most notably due to

the silver that is recovered.

Another factor is the lack of best pracces in dental clinics. For instance, the

use of amalgam separators is an important means of capturing mercury. Separators can be recycled. It is alsorecommended to train dental professionals in the environmentally sound management of dental amalgam. Dental

teaching instuons may need to review and revise their curriculum. Another issue is the potenal diversion of

mercury that has been imported through legal channels for legimate use in dental amalgam to arsanal and small

-scale gold mining (ASGM). It is recommended to use amalgam capsules instead of bulk mercury. By observing these

steps, releases to air, water and soil can be avoided. (refs. 30, 31, 32)

2.2.1. Dental

amalgam

Dental clinic

Other amalgam waste (e.g. non-

contact amalgam)

Suppliers

Avoid diversion

Excess amalgam waste in

dischargeRemoved llings

Use capsules

Figure 9: ESM of amalgam and dental amalgam wastes (compiled based on refs. 13, 18, 29, 30, 31, 32)

Send to recycler or for environ-

mentally sound disposalSend to recycler

Install amalgam separator

Collect, package and label appropriately and ensure environmentally

sound temporary storage at the dental clinic

2.3. Point sources of

emissions and

releases

Mercury is present as an impurity in non-ferrous metal (NFM) ores, natural

gas, mineral oil and coal. When these crude resources are processed,

mercury may be mobilized and released into the environment. This makes

industrial processes with mercury impuries an important source of

emissions and releases as well as wastes contaminated with mercury .

(refs. 33, 34, 35) Dedicated technologies to capture and recover mercury

from the gas and liquid phase are available (ref. 36) (see p. 12).

Recovered mercurycan be sold for allowed uses or otherwise be disposed of safely. In NFM, mercury is oen

recovered as calomel. As previously noted, such compounds, may need to undergo prior treatment. (ref. 33)

The oen large amounts of wastes contaminated with mercury should be managed in an environmentally sound

manner. The respective facilities may have on-site capacity to recover or, where appropriate, treat and dispose it. It

is recommended for governments to ensure the availability of downstream management options (qualified

hazardous waste treatment facilities etc.) (ref. 33). In short, the following opons are available for wastes

contaminated with mercury (see Figure 10 on p. 11):


15/42

i) Recovery/recycling or environmentally sound treatment and disposal:The aim is to separate the mercury

from other components to decontaminate the waste. Various processes are available and may allow re-use of

the components. However, depending on the waste and the technology used, it may be dicult to achieve

suciently low levels. Contaminated fracons and residues have to be properly disposed of.

ii) Disposal in specially engineered landlls or underground facilies: This opon is available following S/S. S/

Sprocesses are available for wastes contaminated with mercury, but may be cost-prohibive for large waste

volumes Direct disposal may be permissible if the wastes are treated to meet naonal acceptance criteria.

iii) Export for recovery/recycling or for environmentally sound treatment and disposal

Wastes are oen deposited on-site, e.g. in tailing heaps or waste dumps. BATs and BEPs should be employed for on-

site waste management. Measures include precipitang mercury as stable compounds, lining and covering the

waste deposit area, and others (refs. 87, 88). The sites will eventually have to be remediated (see p. 13).

Export for

recovery or

environmentally

sound disposal

Recovery/recycling

or treatment

Elemental

mercury

See gure 4 on p. 5

Underground

disposal

Specially

engineered

landll

Residues

contaminated

with mercury

Mercury-free

materials

Re-use

Solid and liquid wastes contaminated with

mercury (e.g. y ash, wastewater, sludge)

See gure 4 on p. 5

Environmentally sound temporary storage on-site

Figure 10: ESM of point sources of emissions of mercury and mercury compounds (compiled based on refs. 13, 18, 33, 34, 35, 36)

Go to top

Recovered mercury or

mercury compounds

Extracon and use of fuels/

energy sources (e.g. natural gas)

Primary and secondary metal

producon (e.g. zinc)

Producon processes with

mercury impuries (e.g. cement)

Ensure dedicated mercury control technologies are in place (BATs and BEPs)

Eligible for disposal?

NoYes

S/S

Contaminated sites

See gure 12 on p. 13

11


16/4212

Others: 51%

Waste:

29%Sulphuric

acid: 10%

Air: 8%

Water: 2%

Waste: 35%

Sulphuric acid: 4%

Air: 1%

Others: 2%

Recovered by-product

mercury: 58%

Use of dedicated mercury

control technologies, such as:

Mercury condenser

Boliden-Norzink

Outokumpu

Bolkem

Merucry output pathways for a smelter without

dedicated technology for mercury control

Mercury output pathways for a smelter with

dedicated technology for mercury control

Box 5: The eect of mercury control technology on output pathways (ref. 33)

Figure 11: Process ow and fate of mercury in NFM processing with dedicated mercury control (based on refs. 35, 37, 89).

Simplied process ow and mercury fate for combined pyro-and

hydrometallurgical processing with dedicated mercury control

Box 6: Treatment of NFM ores and sludge contmainated with mercury in Japan

Japanese legislaon requires zinc and copper reneries to send their ores to a

government endorsed facility for extracon of the mercury prior to processing. The

facility also receives and treats sludge contaminated with mercury. The waste is

treated via roasng in a mulple hearth furnace (photo). This includes ue gas

cleaning via condensaon, scrubbing, electrical dust collecon and adsorponthrough acvated carbon. Emissions are connuously monitored and a limit is set at

0.04mg/m3N. Decontaminated valuable materials are sent back to reneries. (ref. 18) Courtesy: NomuraKohsan Co. Ltd.

Environmentally sound storage and disposal can only be implemented if

mercury impuries in industrial processes are rst captured. This secon

aims to illustrate merucry capture with the example of NFM producon.

Depending on the specic processes used, mercury may be released in

gaseous form, remain in liquid and solid wastes or be trapped in sulphuric

acid which is generated as a by-product. Figure 11 shows the ow and the

fate of mercury in a plan with combined pyrometallurgical processing and dedicated mercury control technology.

Dedicated mercury control has a strong inuence on the output pathways. In the le pie chart (Box 5), others

indicates unaccounted mercury that has been lost in the process. Emissions are signicant. As the pie chart on the

right shows, mercury-specic controls are capable of capturing most of the mercury and minimizing releases.

2.3.1. Mercury

capture in non-

ferrous metals


17/4213

2.4. Manufacturing

processes in which

mercury or mercury

compounds are used

Mercury should be captured and wastes contaminated with mercury managed in an ESM. (ref. 39)

VCM producon, acetaldehyde producon in which mercury or mercury compounds are used as a catalyst,

sodium or potassium methylate or ethylate, producon of polyurethane using mercury containing catalysts

Solid and

liquid wastes

contaminated

with meruy

Contaminated soil and sediment

See gure 10

on p. 11

On-site treatment

(e.g.

phytoextracon, in

-situ stabilizaon,

vitricaon)

On-site treatment

(e.g. acid

extracon, ,

retorng,

vitricaon)

Contaminated (ground)water

On-site treatment

(e.g. (co-)

precipitaon,

membrane

ltraon)

O-site treatment

(e.g. biological

treatment)

Recovered

mercury

See gure 4

on p. 5

Residues

contaminated with

low levels of mercury

See gure 10 on p. 11

Decontaminated soil,

treated euent etc.

Re-use (e.g.

as backll)Dispose

Manufacturing processes with intenonal uses of mercury or mercury

compounds (notably VCM, acetaldehyde, sodium/potassium methylate/

ethylate or polyurethane producon) may be a source of mercury

emissions and releases. In VCM producon, for instance, some of the

mercury is lost in the catalyst during processing. (refs. 34, 35, 38)

It is recommended to use best available techniques (BATs) and best

environmental pracces (BEPs) to avoid such emissions and releases.

Figure 12: ESM in manufacturing processes using mercury or mercury compounds (refs. 13, 18, 40)

Soil washing at a former waste processing and recycling facility (US)

Mercury-contaminated soil, sludge and sediment from a former waste processing and recycling facility was treated

using soil washing. The treatment reduced concentraons of inorganic mercury from 100 mg/kg to 1 mg/kg.

Residual sludges were disposed o-site as non-hazardous waste, and the treated soil was used as backll. (ref. 40)

Box 7: Soil washing at a former waste processing and recycling facility

Similar to many of the sources discussed previously, manufacturing processes with intenonal mercury uses may

generate sites contaminated with mercury. These may also be found at hazardous waste processing and recycling

facilies. The surface and sub-soil, sediment, groun and washing water should be adequately treated. A number

of processes are available for on and o-site treatment (see gure 12) (ref. 40). Under the Minamata Convenon,

Pares are encouraged to idenfy, assess, prioze, manage and, as appropriate remediate contminated sites

(Arcle 12).

Excess

mercury

See

gure 4

on p. 5

and

gure

13 on

p. 14


18/42

Figure 13: Preparaon for permanent storage of metallic mercury and site remediaon (refs. 42, 43, 44, 45))

Detailed guidance documents have been developed by the World Chlorine Council/Euro Chlor. These are available

at hp://www.unep.org/chemicalsandwaste/Mercury/PrioriesforAcon/ChloralkaliSector/Reports/tabid/4495/

language/en-US/Default.aspx. Updated materials will soon be available at hp://www.worldchlorine.org.

14

Mercury cell chlor-alkali facilies which close or convert to alternave

technologies may have signicant amounts of surplus mercury requiring

ESM. Under the Minamata Convenon, where a Party determines the

mercury from decommissioning is excess, it shall dispose such mercury in

an environmentally sound manner (Arcle 3).

A number of preparatory steps are necessary prior to decommissioning.

This includes the preparaon of a well documented plan of acon to beapproved by the authories, idencaon of downstream management opons, and provision of equipment for

mercury handling, including storage containers. Decommissioning can be grouped into the following three areas:

i) Treatment and disposal of mercury contaminated waste

ii) Recovery and storage/disposal of excess elemental mercury

iii)Site remediaon (see gure 13)

Liquid

from the

cells

Sludge

and

solid

Retorng

Elemental mercury

Puricaon

Transfer into adequate containers and ship

o-site for storage/treatment/disposal

Liquid from

pipes and

boom of tanks

Transfer into

empty cell

Excess mercury

stored at the

plant

Sell/re-use

Determine the quanty of mercury to be recovered

Excess?

Yes

No

Closure/conversion of (a) mercury cell CA facility(ies)

Waste

Sell/re-use within CA

sector, in accordance

with naonal law

Make a survey of all plants, buildings and

associated equipment to be

decontaminated and/or demolished

Contaminated equipment, building,

surface soil, sub-soil, washing water and

groundwater

On-or o-site treatment and

decontaminaon (e.g. in-situ vitricaon,

water washing, retorng) as far as

reasonably praccable

Decontamina-

ted parts

Re-use Dispose

Contaminated

residues

See gure 10

on p. 11See gure 7 on p. 8

2.4.1.

Decommissioning of

mercury cell chlor-

alkali facilies


19/42

Temporary storage of mercury-added products in the San Lazaro Hospital (Philippines)

In response to an administrave order mandang gradual phase-out of mercury in the Philippine health care

sector, the San Lazaro Hospital established a mercury management team, among others responsible for the safe

temporary storage of spent mercury-added measuring devices and uorescent lamps. Safety measures were

implemented to comply with the Department of Healths Guidelines on Interim Storage of Mercury Devices.

Placed in the original

box and sealed with

duct tape

Wrapped in a labelled

plasc bag as primary

container

Placed in a labelled

secondary container

and sealed with duct

tape

Stored in dedicated

facility in distance of

paents area and

oces

Step 1 Step 2 Step 3 Step 4

Courtesy all pictures: Karen Abejar, Arago

15

Box 8: Temporary storage of mercury-added products in the San Lazaro Hospital (Philippines) (refs. 46, 47)

Chapter 3: Temporary storage, handling, transport and traceability

Temporary storage means pung mercury wastes in a place where it will not

contaminate the environment and can easily be moved/retrieved for later

disposal operaons. It is limited in me and should be undertaken in an

ESM. (refs. 13, 20)

Temporary storage serves to store mercury wastes pending furthercollecon, treatment, disposal or export. It may therefore occupy a

parcularly central posion for countries lacking the necessary infrastructure to ensure the environmentally sound

treatment and disposal of mercury wastes. Thus, temporary storage may serve to collect mercury waste before it is

exported for environmentally sound disposal operaons or it may be used as a temporary measure unl

domesc opons are available.

Arcle 10 of the Minamata Convenon covers the interim storage of mercury other than waste mercury. While this

secon covers the temporary storage of mercury wastes, the same precauons should be observed regardless of

whether mercury is stored as a commodity or as a waste.

Environmentally sound temporary storage is pracced in a number of sengs which should be t for the variouswaste streams to be stored:

i) In public instuons (e.g. schools, hospitals) (see box 8): It is recommended to store spent mercury-added

products only for a short period of me and send them to centralized facilies or directly for recycling.

Storage should be in a secure outdoor locaon, if possible, to prevent exposures to mercury that may be

released from mercury devices that are broken during handling. (ref. 13)

ii)

On-site at industrial facilies (see box 9 on p. 16): Wastes contaminated with mercury or mercury

compounds as well as by-product or excess mercury generated by industry are typically stored on-site, e.g. in

tailing heaps or warehouses (ref. 33). In order to avoid emissions and releases, governments should ensure

that on-site storage is pracced in an ESM and that downstream management opons are available.

3.1. Temporary

storage


20/42

iii) In centralized facilies/hazardous waste recycling plants: Mercury wastes from households, public

instuons and industry can be collected in centralized facilies that are also used for other hazardous

wastes. Where available, most types of mercury wastes can be directly sent to recycling/treatment plants.

iv) In a dedicated facility (see box 10): Governments may wish to establish dedicated facilies for collecon and

temporary storage of mercury wastes, especially for larger quanes from industry. It is recommended for

such facilies to be (a) located close to large waste generators, provided low populaon density around thesite, and (b) well-connected to the transportaon network and treatment or disposal facilies.

Temporary storage of mercury contaminated sludge at a non-ferrous metals plant ( Japan)

Packaging: The sludge

is put in a double

plasc bag, placed in a

stainless steel drum

and properly labeled.

Storage and transportaon: The

drums are kept and collected in

an indoor warehouse unl they

are sent to a dedicated mercury

treatment facility by truck and a

railroad container.

Both pictures courtesy: Japan Mining Industry Associaon

Temporary storage should be done in compliance with technical requirements (such as the use of vapor detecon

instruments) including relevant internaonal standards and regulaons and naonal law (ref. 13). Detailed

technical informaon on the sing, design and operaon of temporary storage facilies is available in the Basel

Technical Guidelines (para 139147). Health Care Without Harm (HCWH) and the Global Environment Facility

(GEF) developed guidance on cleanup, temporary or intermediate storage, and transport of mercury waste from

healthcare facilies available at: hp://www.gefmedwaste.org/downloads/Guidance%20on%20Cleanup%

20Storage%20and%20Transport%20of%20Mercury%20from%20Health%20Care%20July%202010.pdf.

Temporary storage in Las Cuevas by Minas de Almaden (MAYASA) (Spain)

MAYASA, a former primary mining company, is storing wastes consisng of mercury in an old vehicle maintenance

hangar which was retroed for this purpose.

1: The six stainless steel storage tanks for liquid mercury

2: The current warehouse for the handling of mercury asks and

large mercury vessels

Courtesy: MAYASA

The elemental mercury is of 99.9% purity.

A safety container was built and six stainless steel

storage tanks were installed on top of it. The oorshave a slight slope directed to a collecng basin.

Handling areas have waterproof protecve epoxy-

based paint on walls and ooring.

The site is located in an area not prone to

earthquakes and in distance of agricultural

pracces and towns.

16

Box 9: Temporary storage of mercury contaminated sludge on-site at a non-ferrous metals plant (Japan) (ref. 18)

Box 10: Temporary storage in Las Cuevas by Minas de Almaden (MAYASA) (Spain) (refs. 48, 49, 50)

Important steps: Governments may wish to take the following steps

Develop guidance and awareness-raising materials for temporary storage by public instuons and industry.

Choose and retrot (a) suitable site(s) for centralized temporary storage of mercury wastes.

Regulate maximum duraon, storage capacity, safety/environmental protecon requirements and liability.


21/42

Mercury wastes must be handled with great care in order to prevent

evaporaon and spillage of elemental mercury into the environment . It is

therefore necessary to ensure adequate handling, packaging, labeling and

transport according to the technical requirements spulated by naonal law

as well as internaonal rules and obligaons. (ref. 13)

For detailed informaon, see the Basel Technical Guidelines (para 132-147).

3.2. Packaging,

transport and

traceability

Packaging:

The containers in which mercury wastes are transported provide the most direct barrier to prevent releases.

Mercury wastes must therefore be carefully packaged in appropriate containers before shipping them to

designated treatment, storage or disposal facilies. (see boxes 11-14).

Mercury wastes should be placed in a gas-and liquid-ght container with appropriate labeling (disncve mark

indicang that it contains toxic mercury and is corrosive, origin, weight, shock resistance etc.). Containers should

always be coated from the outside and kept in a dry locaon to prevent corrosion. No damage to the structural

integrity of the container should be given. No materials adversely reacng with mercury should have been

previously stored in the container. (ref. 13)

Box 13: Steel barrel (3, 14)

Wastes consisng of mercury should be stored in

specialized containers, for example mercury

asks (2.5 liter/34.5 kg), which are also the standard

unit for trading mercury. Other oen used container

types are 1 ton stainless steel pressure reptacles.

(Courtesy:Umwelt Technik Metallrecycling GmbH)

Wastes containing mercury must be

transported in a way that prevents them

from breaking and releasing mercury.

125 liter UN-approved plasc drum (courtesy:

Umwelt Technik Metallrecycling GmbH)

Sludge and waste with

metallic mercury may be

transported in approved

plasc or steel barrels, e.g.

this UN-approved 110 liter

stainless steel drum withepoxy lining

17

Box 11: Mercury asks and receptacle (refs. 3, 14)Box 12: Plasc drum (refs. 3, 14)

Transport: Box 14 (see next page) illustrates the

environmentally sound transport of mercury

wastes. Prior to transportaon, conngency plans

should be prepared in order to minimize

environmental impacts associated with spills, res

and other potenal emergencies. Dilligent

acceptance controls are necessary at thedesnaon (see box 15).


22/42

Traceability of mercury wastes throughout management

Traceability is a set of acons, measures and procedures to idenfy and record every acvity of hazardous waste

management from generaon to disposal. Mercury and mercury wastes must be traceable throughout the

lifecycle, including aer nal disposal. Traceability applies to relevant actors upstream (e.g. waste generators) and

downstream (e.g. recyclers, disposal facilies). Informaon on the characteriscs and quanty of the mercury and

mercury waste in queson as well as the risks associated with its management should be available atall mes. Legal mechanisms should be in place (e.g. audits, inspecons). It is recommended to request

detailed reports and tracking records from dealers, recyclers, disposers and others involved.

(ref. 60)

Box 16: The signicance of traceability

Internaonal reference documents:

Naonal law as well as internaonal standards should be adhered to during packaging, labelling, transport and

transboundary movement of mercury wastes. Below is a list of important documents that should be consulted:

Basel Convenons Manual for the Implementaon of the Basel Convenon (ref. 53)

IMOs Internaonal Marime Dangerous Goods Code (ref. 54)

ICAOs Technical Instrucons for the Transport of Dangerous Goods by Air (ref. 55)

IATAs Dangerous Goods Regulaons Manual (ref. 56)

UNECEs Recommendaons on the Transport of Dangerous Goods, Model Regulaons (ref. 57)

UNECEs Globally Harmonized System of Classicaon and Labelling of Chemicals (ref. 58);

OECDs Harmonized Integrated Classicaon System for Human Health and Environmental Hazards of

Chemical Substances and Mixtures (ref. 59).

Throughout the logiscs chain, it is crucial to ensure the traceability of mercury wastes (see box 16). This will help

to ensure that they are not diverted for illegimate uses or inadequately disposed.

Transport of wastes consisng of mercury (US)

Box 14: Transport of wastes consisng of mercury (US) (ref. 54)

Pallets inspected; drums and pallets baded for stability;

loads blocked and braced in carriers conveyance

All shipments complied with U.S.DOT requirements for

shipment of hazardous materials

Cered hazardous material haulers

Stringent recepon control, incl. vapor measurement

18

Acceptance control

Upon arrival at treatment, storage or

disposal facilies, mercury wastes must be

inspected. This includes vapor measurement

and chemical analysis. If acceptance criteria

are not fullled, the waste should be re-

packaged and sent back to the owner.

Box 15: Acceptance control

Courtesy:Defense Logiscs Agency

Courtesy:K+S Entsorgung GmbH


23/42


24/42

Mercury waste is fed into the inclined rotary kiln

Kiln heated to 600C 800C

Mercury is vaporized and enters o-gas stream

Secondary combuson at 850C-1100C

Exhaust gas is quenched (cooled by water sprays)

and rapidly brought to low temperatures (ca. 4

Mercury is condensed and collected through a

scrubber as a slurry for puricaon

Ideal for baeries and soil with low mercury content

Carried out at under-pressure;

Nitrogen can be added to create inert atmosphere

The rotary moon enables an even and fast

distribuon of heat through the waste which allows a

rapid evaporaon of mercury

Post-combuson chamber to ensure destrucon of

hydrocarbons , carbon monoxide and halogens

Courtesy: Nomura Kohsan Co., Ltd.

Box 17: Rotary kiln (ref. 18)

Box 18: The end-cut/air-push recycling process for linear uorescent lamps (ref. 18)

The recycling methods used for wastes containing mercury are oen very specic and mulstage, whereas for was-

tes contaminated with mercury methods are applied that oen are used for other hazardous wastes as well.

A number of dierent technologies are available for the environmentally sound recovery and recycling of wastes

contaminated with mercury as well as mercury-added products. Boxes 17, 18 and 19 illustrate some examples.

20

Rotary kiln

The end-cut/air-push recycling process for linear uorescent lamps

The aluminium end caps of linear uorescent lamps are cut by heat. Air push nozzles blow the mercury -

phosphor powder adsorbed from the tube. The metals, glass and merucry-containing phosphor powder are

then collected in dierent vessels via a dry separaon technology. The recovered glass is of very high purity.

Where necessary, the method also allows for seperaon of the dierent types of powder. Unlike in other

processes, the mercury is not extracted; instead, the powder is sent to lamp manufacturers for re-use.

Courtesy: SARP Industries


25/42

Management of residues, emissions and releases:

It is oen not possible to extract all of the mercury contained in the waste. Moreover, a small, but signicant

proporon will be lost during treatment processes. Some mercury will vaporize during pre-treatment, remain in

the y/boom ash during thermal treatment or may contaminate wastewater.

It is essenal to keep a mass balance, i.e. to monitor the amount of mercury entering treatment processes

on the one hand and the amount of mercury recovered on the other.

Treatment must take place in a closed system with negave pressure, so as to prevent vapor emissions.

Exhaust air must be captured in lters, such as acvated carbon beds.

Emissions and releasesshould be connuously monitored.

The mercury residuals from processing of mercury wastes must undergo further treatment or be disposed of in an

ESM. Gas and wastewater treatments will generate wastes contaminated with mercury (e.g. saturated carbon)

which will then also need to be treated and/or disposed (see box 20). (refs. 13, 18, 40)

Chemical

precipitaon

Chemical precipitaon: Typically the nal step aer all organic content has been destroyed.

Uses chemicals (e.g. sodium sulphide) to transform dissolved contaminants into aninsoluble solid. The precipitated solid is removed by claricaon or ltraon.

Chemical

oxidaon

Adsorpon

treatment

Adsorpon treatment: Adsopron materials hold mercury on the surface through chemical

forces. Mercury or mercury compounds are adsorbed as liquid wastes and pass through a

column. Adsopron materials include acvated carbon, zelolite and ion exchange resins.

Chemical oxidaon: oxidizing reagents (e.g. sodium hypochlorite) are used to destroy the

organics, to convert mercury into a soluble form and to form mercury halide compounds

which are sent for further processing (acid leaching, precipitaon). Used for aqueous

wastes containing mercury.

Chemical

leaching

An aqeuous process that solubilises mercury by bringing it in contact with a leaching

soluon. It is paroned to the liquid phase and thus removed from the waste matrix. The

solubilized mercury is further treated (e.g. precipitaon, carbon adsorpon). Good for

inorganicmercury forms, less eecve for elemental mercury.

Box 20: Wastewater and gas treatment (ref. 40)

Recycling of mercury-added baeries via the Sumitomo process

Following manual separaon, the mercury-added baeries are

pyrolized at temperatures of 700800C. In the exhaust gas

puricaon plant, mercury is washed out and condensed as a

metal in a sludge. The sludge is sent for further processing in the

mercury disllaon plant, where elemental mercury of 99,995%

purity is recovered. Apart from elemental mercury, the process

produces ferro-manganese, zinc and slag.

Box 19: Recycling of mercury-added baeries via the Sumitomo process (ref. 18)

Courtesy: Batrec Industrie AG

21

Wastewater and gas treatment


26/4222

A guiding principle for the ESM of mercury waste is to reduce

hazardousness and the risk of releases as soon and as much as

possible. An essenal means of doing so is to treat mercury waste.

Mercury wastes can be chemically stabilized and/or physically

solidied. In many cases, a combinaon of both is used. This isreferred to as stabilizaon/solidicaon (S/S). (ref. 61)

5.1. Stabilizaon/

solidicaon

Stabilizaon

Stabilizaon processes reduce the hazardousness of the constuents in the waste . Elemental

mercury is brought into reacon with chemical agents that convert it into a substance that is

thermodynamically more stable, less soluble and less volale, making it less mobile and so

reducing release and exposure potenal. (refs. 61, 62, 63)

Solidicaon

Solidicaon processes change the physical state of the waste without changing the

chemical properes of the waste. Mercury wastes are embedded in a stable matrix and thussealed from the environment. Micro-encapsulaon means mixing the waste with the

encasing material. Macro-encapsulaon means pouring the encasing material over and

around the waste mass, thus enclosing it in a solid block.(refs. 50, 61, 62, 63)

S/S is used for wastes consisng of elemental mercury as well as wastes contaminated with mercury (e.g. soil or

sludge), usually with a low mercury content rendering recovery technically and/or economically unfeasible

Box 23 and 24 describe two of the most commonly used approaches. The rststabilizaon of elemental mercury

as mercury sulphideis a one-step process used for elemental mercury. The secondstabilizaon and microencap-

sulaon of mercury wastes in a sulphur polymeric matrixis a two-step process that can be used for various types

of mercury wastes.

S/S technologies may serve to:

reduce vapour pressure and solubility

reduce mobility/disperability

enhance physical strength

S/S may thus oer praccal, cost and health benets:

easier and cheaper to handle

safer storage and disposal

isolaon from the biosphere

Figure 15: The eects and benets of S/S (refs. 13, 18, 61, 63, 64)

Courtesy: Kummel Consulng AB

Sulphur and elemental mercury are mixed under heat in a vaccum mixer, thus

reacng to mercury sulphide.

Reported characteriscs of the nal product:

Product is a powder with no detectable releases of mercury vapour

Concentraon aer leaching with water is less than 0.002 mg/kg

Weight increases by ca. 16%, volume ca. 6-fold

Box 23: Sulphur stabilizaon of elemental mercury (refs. 18, 61, 63)

Chapter 5: Disposal Opons

Box 22: Solidicaon

Box 21: Stabilizaon

The objecve is to immobilize the mercury and to isolate it from the biosphere, thus making it t for storage and/or

nal disposal.

Potenal eects and benets of stabilizaon/solidicaon

Sulphur stabilizaon of elemental mercury


27/42

Mercury is stabilized with sulphur as mercury sulde and then incorporated and microencapsulated in a poly-

meric sulphur matrix. Characteriscs of the nal products:

Monolithic block aer the treatment of metallic mercury from thechlor-alkali sector.

Monolithic block aer the treatment of zinc producon waste.

Monolithic block aer the treatment of uorescent lamp dust.

Courtesy: MAYASA

Concrete-like resistance; very low

porosity

Hardly reversible process

No unreacted mercury

Weight increases ca. 3-fold, volume ca.

13-fold

Leaching values (both monolithic and

crushed samples) in compliance with EU

standard (


28/4224

5.2. Long-term storage/

aboveground warehouse

storage

Aboveground warehouse storage refers to long-term storage (i.e.

several decades). The mercury waste is removed from the market

but not subjected to naldisposal. of mercury without a nal

disposal soluon. Some countries may wish to store waste consisng

of mercury in the long-term unl other opons are available. Long/

term storage can be realized in any suitable aboveground facility

that is specially designed for this purpose. (ref. 13)

Governments may consider this opon if the following condions are met:

a) considerable amounts of elemental mercury need to be stored,

b) naldisposal opons are not available (e.g. because S/S is not available), and

c) export is not considered an opon

Safety requirements: Special precauons have to be taken to allow safe storage for several decades. The

aboveground warehouse storage of elemental mercury in the US may serve to indicate the opmal level of safety

measures. For details, see box 26 below.

The challenge...

Elemental mercury stockpiled in more than 40-

year old asks in three separate locaons

...and the response

4,436mt (128,660 asks) elemental mercury

permanently stored in a single storage facilitywith stringent safety measures in place.

All pictures courtesy of Defense Logiscs Agency

Alternave opons considered in the MM EIS

No acon, i.e. to connue storage at exisng sites: This

opon did not meet the DNSCs goal of reducing the

number of sites.

Treatment for disposal: When the decision was

taken, no proven technologies were commercially

available.

Treatment for storage: The DNSC found that mercury

can be safely stored in its elemental form. Moreover,

treatment costs were considered too high.

Sales: This opon was rejected due to

environmental concerns.

A Mercury Management Environmental Impact Statement (MM EIS) was conducted by the Defense Naonal

Stockpile Center (DNSC) to assess the opons. Long-term storage in a single consolidated facility was selected.

Mercury over packing project

During the EIS, rst preparatory acons were taken. 128,660 asks were inspected,

cleaned, ghtened and then over packed: The asks were placed in epoxy -coated steel

drums with layered protecon (absorbent pads, plasc liners, locking ring etc.).

Aboveground warehouse storage of elemental mercury (US)

Over the course of the past 50 years, the U.S. Department of Defense (DOD) had been collecng and storing its

surplus elemental mercury. While some of those excess stocks were sold over me, due to increasing concerns

about the adverse eects of mercury, the DOD has kept its enre surplus in safe storage.


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Warehouse improvements and safety measures

Installaon of re suppression and security systems

Installaon of ooring sealant and ramped containment dikes

Stringent emergency protocol

A venlaon system exerts control on mercury vapor emissions

Safety and storage equipment includes mercury vapor detecon

instruments and spill response kits

Eventually the mercury was transported to Hawthorne, Nebraska in compliance with the requirements for the

shipment of hazardous materials. A stringent inspecon and recepon protocol was followed.

Lessons learnt:

Centralized storage facilies have the advantage of saving costs compared to mulple sites.

Exisng facilies can be retroed for use as mercury storage facility.

Properly designed asks oer good protecon against vapor emissions.

If sucient safety measures are in place, aboveground warehouses are an environmentally sound opon.

Prior to shipment, the selected warehouse was retroed to comply with regulatory storage requirements.

Training was conducted and the operang permit issued.

25

Challenges

Not a permanent soluon: mercury remains in

the biosphere and must be acvely managed

Very high safety standards needed

Requires economic, instuonal and polical

long-term stability

High long-term operaonal costs

Opportunies

Many potenally suitable sites that could be

retroed available in most countries

Implementaon within several years

Most consolidated opon; exisng experience

Risk assessment less complex than for

permanent storage

No need for previous stabilizaon

Important steps: countries may wish to

develop site selecon criteria, idenfy potenal sites and conduct long-term environmental impact assessments;

connue invesgang long-term soluons, including S/S and underground disposal/SELs; and

enter into negoaons with private holders of mercury regarding liability and cost-sharing.

Table 1: Challenges and opportunies associated with aboveground warehouse storage (refs. 11, 14, 48)

Box 26: US aboveground warehouse storage (refs. 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77 )


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Duraon:Landlls can be specially engineered to be environmentally safe for a prolonged period of me, provided

that proper precauons and ecient management are guaranteed. However, it is important to menon that even

stabilized mercury waste cannot be indenitely stored in landlls. (refs. 12, 13, 18, 79)

Risks: Depending on the operang condions and the equipments used for closure of the cells, storage of

mercury waste in landlls may become a source of releases in the future. In the long-term, the surface sealing may

become porous and oxygenated rainwater and air may penetrate the landll. Bioc and abioc processes may

mobilize even stabilized mercury and methylmercury may be formed. (refs. 12, 13)

It is therefore quesonable whether it is enough to apply standard leaching tests in order to decide on the

applicability of stabilized mercury waste for landlling. The leachability and volality of mercury in solids strongly

depends on the physical and chemical pre-condions at the place of storage. These might not be the same as

presumed in standard leaching procedures. (ref. 61)

Stabilized/solidied mercury wastes Solid wastes contaminated with mercury fullling the

naonal acceptance criteria

Spent mercury-added products

Though some spent mercury-added products might be eligible under naonal legislaon,

this is not recommended since mercury may be easily released into the environment.

Wastes consisng of elemental mercury

Liquid mercury is highly volale

and may methylate in SELs.

(Semi-)liquid wastes contaminated with mercury

Mercury contained in liquid

wastes may easily mobilize.

26

5.4. Specially engineered

landll

A specially engineered landll (SEL) is an environmentally

sound system for solid waste disposal and is a site where solid

wastes are capped and isolated from each other and from the

environment. (ref. 13)

The waste is stored aboveground or near the surface below

ground in a retrievable manner.

Eligible mercury wastes: Following S/S, wastes containing or contaminated with mercury that meet the

acceptance criteria dened by naonal or local regulaons, may be disposed of in SELs. Most countries specify

leaching limit values, concentraon and/or content thresholds (see the examples for the EU and the US in table 2).

EU US

Only hazardous wastes with leaching limit values of

2mg Hg/kg dry substance at a liquid-solid rao of 10

L/Kg (for hazardous waste).

Only low concentraon mercury wastes: Treated

mercury waste must leach less than 0.025 mg/L mercury

(by TCLP tesng).

Figure 18 provides recommendaons in terms of which wastes may (not) be disposed of in SELs.

Table 2: Eligibility criteria for landll disposal in the EU and the US (ref. 13)

Figure 18: 2: Eligibility of mercury wastes for disposal in a SEL (refs. 13, 18, 64, 65, 78, 79, 81, 82)


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Challenges

Safety may only be predicted for some decades

Requires prior stabilizaon

Stabilized mercury is not thermodynamically

stable in SEL

May become a future source of releases

Opportunies

Well established concept in many countries;

experience with other hazardous wastes

Relavely low investment and operaonal costs

If prior S/S, the mercury waste is isolated from

the biosphere

Table 3: Challenges and opportunies associated with storing mercury wastes in SELs (refs. 10, 13, 18, 20, 66, 80, 81, 82)

Important steps: countries may wish to

establish a permit system, spulang leachate and gas control systems, closure and post-closure measures etc.;

idenfy exisng SELs that could be retroed for the disposal of stabilized mercury; and

analyze the long-term behavior of the stabilized mercury waste in the specic sengs of the facility.

Safety requirements: Preparaon, management and control of the landll must be of the highest standard to

minimize the risks to human health and the environment. This should similarly apply to the process of site selecon,

design and construcon, operaon and monitoring, closure and post closure care. Sites with favorable natural and

arcial containmentproperes should be selected and specially engineered for the purpose of storing mercury

waste. Overall engineering should ensure isolaon from the environment that is as complete as possible. (ref. 13)

Special requirements to prevent leakages and contaminaon of the environment include, among others:

The waste is stored in a retrievable manner in dedicated cells, separate from other wastes

Control and oversight procedures are in place; periodic monitoring and evaluaon is undertaken

Boom (operang phase) and top-liner (closure and post-closure phase) installed

For detailed informaon on safety measures and specic site criteria, it is recommended to consult the Basel Tech-

nical Guidelines (para 188-191) and the Basel Technical Guidelines on Specially Engineered Landll.

This specially engineered landll is completely shut o from the outside natural world. It is enclosed

in waterght and reinforced concrete and covered with equipment prevenng rainwater inow such

as a roof and a rainwater drainage system

Box 27: Specially Engineered landll (ref. 13)

Scheme of a specially engineered landll

27


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5.5. Underground

disposal

Underground disposal means to place waste in an ordered manner in deep

geological cavies (e.g., in an underground mine). It is considered as a

nal, irreversible disposal operaon.

The idea is to permanently isolate mercury waste from the biosphere by

including it completely and permanently in a suitable host rock via several

natural and arcial barriers. No or limited supervision and

maintenance is necessary. Underground storage may thus be considered anal disposal soluon. Underground storage may serve to isolate

mercury waste from the biosphere for geological periods of me.(refs. 10, 12, 13, 20) . Figure 19 provides

recommendaons in terms of which wastes may (not) be disposed of underground:

Stabilized/solidied mercury wastes Solid wastes contaminated with mercury full-

ling the naonal acceptance criteria

Wastes consisng of elemental mercury

Currently, liquid mercury is not accepted for underground storage. However, a

recent study suggests that the disposal of liquid mercury is feasible, provided

that it is of high purity and that addional safety measures are in place (ref. 12).

Spent mercury-added products

Mercury-added products may

break and release liquid mercury.

(Semi-)liquid wastes contaminated with mercury

Mercury contained in liquid

wastes may easily mobilize.

?

Potenal sites: Potenal sites could be disused underground mines with suitable geochemical condions, once

they have been specically adapted for the purpose (82). Potenal host rocks include the following:

i) Salt rock: Considered impermeable to liquids and gases and the most eecve barrier for long-term storageof

hazardous waste. Yet, a minimum thickness of the salt layer is needed to ensure safe encapsulaon. (ref. 82, 83)

ii) Clay formaons: Also considered as good barriers, although to a lesser extent impermeable (refs. 82, 83).

iii)

Hard rock formaons: Complete enclosure technically not feasibledue to high rock permeability and possiblefractures. The site has to be carefully assessed and addional technical barriers must be in place (refs. 82, 83).

Prototype container potenally suited for permanent storage (Argenna)

During the UNEP Mercury Storage and Disposal Two Countries

Project in Lan America, engineers of the Naonal Instute for

Industrial Technology (INTI, Argenna) adapted a proposal inially

developed for radioacve waste to explore the possibility of

permanently storing mercury waste. The idea: A permanent

underground storage structure based on the use of steel reinforcedconcrete cells in which drums containing solidied waste are stored.

28

Box 28: Prototype container potenally suited for permanent storage (ref. 84)

Figure 19: 2: Eligibility of mercury wastes for underground disposal (refs. 10, 12, 13, 19, 20, 81, 82)

Courtesy: INTI


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Underground disposal in salt mines (Germany)

In Germany, mercury containing waste is stored underground in salt mines. Mercury-contaminated soils and

components, mercury-contaminated demolition waste from the chlor

-alkali sector, and contaminated glass

breakage were disposed in the underground facility in the city of Herfa Neurode. The deposit lies at depths of 500

to 800m and thus far below the groundwater.

Operaon

Samples taken at entrance

Acceptance control (chemical analysis)

Informaon pertaining to storage me

and locaon recorded

Implementaon monitored by ocial

authories

Mul-barrier system

Natural barriers:

Salt (gasght): 300m

Clay (waterght): 100m

Bunter stone: 500m

Arcial barriers

Waste packaging

Brick walls

Field dams

Waterght sha sealing

Storage arrangement

Stored in a retrievable way in disused, excavated

area of the mine, remote from extracon area

Closing of the storage chambers

Salt dams or stonewalls to separate the storage

cells; storage in separate lockable chambers

Connuous monitoring of mercury vapor

Challenges

-Some countries might not meet the condions required to

host an underground site (geographic, legal, polical etc.)

-Requires signicant investment

-Demanding and lengthy selecon process and assessment

Important steps countries may wish to take include to:

develop site selecon criteria, idenfy sites and conduct long-term site-specic risk and safety assessments;

put technical barriers in place (containers, dams, sealing etc.) to complement geological barriers; and

secure nances and ensure private sector involvement (polluter-pays).

Opportunies

+ Pre-treatment opons (S/S) are available

+ No aercare measures needed (low operaonal costs)

+ Allows complete isolaon from the biosphere

+ Exisng experience with hazardous waste, incl. mercury

+ Globally, many exisng rock types with suitable geology

Costs: Signicant investment is necessary for the adjustment of the underground storage design, i.e. the

preparaon of storage chambers, and the site assessment and long-term safety assessment.

Co-storage of other hazardous wastes is possible to save costs; however, these must be stored in separate cells.

Once the waste is sealed o, substanal operaonal costs can be saved compared to the alternaves. (ref. 82)

Informaon on site selecon criteria and safety measures can be found at the IAEAs Geological Disposal of

Radioacve Waste: Technological Implicaons for Retrievability (hp://www-pub.iaea.org/MTCD/publicaons/

PDF/Pub1378_web.pdf) (ref. 86).

29

Table 4: Challenges and opportunies associated with the permanent storage underground of mercury (refs. 13, 18, 65, 82)

Box 29: Underground disposal in salt mines (Germany) (ref. 85)

Courtesy: K+S Entsorgung GmbH
http://www-pub.iaea.org/MTCD/publications/PDF/Pub1378_web.pdfhttp://www-pub.iaea.org/MTCD/publications/PDF/Pub1378_web.pdfhttp://www-pub.iaea.org/MTCD/publications/PDF/Pub1378_web.pdfhttp://www-pub.iaea.org/MTCD/publications/PDF/Pub1378_web.pdfhttp://www-pub.iaea.org/MTCD/publications/PDF/Pub1378_web.pdfhttp://www-pub.iaea.org/MTCD/publications/PDF/Pub1378_web.pdfhttp://www-pub.iaea.org/MTCD/publications/PDF/Pub1378_web.pdf


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Costs: Whether export is a cheaper soluon than the alternaves depends on a number of factors, e.g. the

volume of mercury wastes. It is dicult to give general cost esmates, as they vary greatly (e.g. due to energy

prices). Main cost factors include insurance, packaging, customs, freight and shipment fees, and the costs or

treatment/storage/disposal in the country of desnaon.

Export of catalysts contaminated with mercury ( Indonesia)

Picturescou

rtesyofBatrec

Indonesia has a signicant gas extracon industry. This sector

generates large amounts of wastes contaminated with mercury,

including catalysts. No recycling facility was available domescally.The spent catalysts, contaminated with up to 15% of mercury, are

exported to Switzerland for decontaminaon and recycling.

30

Box 31: Export of catalysts contaminated with mercury (Indonesia) (ref. 18)

The export of mercury waste is a parcularly important opon for countries

lacking the necessary infrastructure for environmentally sound treatment,

storage or disposal (see examples in boxes 30-32). It may also be the

preferred choice for countries with relavely small amounts of mercury

waste or where the establishment and operaon of facilies is considered

too costly. Some countries may see export as an interim soluon, unl

domesc facilies become available.

Legal consideraons: Where applicable, all shipments should be made in accordance with the rules and

procedures of the Basel Convenon (see box 29). Arcle 11 of the Minamata Convenon allows the export of

mercury waste for environmentally sound disposal for Pares to the Basel Convenon. Where the Basel

Convenon does not apply, internaonal rules, standards and guidelines must be taken into account. The imporng

country must have the infrastructure to guarantee ESM and permit the import according to its naonal legislaon.

5.6. Export of

mercury wastes for

evironmentally

sound disposal

Transboundary movement of mercury waste is only allowed if:

The state of export does not have

the technical capacity and the ne-

cessary facilies, capacity or sui-

table disposal sites for environ-

mentally sound disposal

The wastes in queson

are required as raw mate-

rial for recycling or

recovery industries in the

state of import

The transboundary move-

ment in queson is in ac-

cordance with other crite-

ria decided by the Pares

Does the exporng Party have reason to believe that the

wastes in queson will not be managed in an ESM?No exportYes

No

Observe Prior Informed Consent (PIC) requirements during nocaon, consent and issuance of

movement documents, transboundary movement, and conrmaon of disposal.

or or

Box 29: Export of mercury waste under the Basel Convenon

Export of mercury waste under the Basel Convenon


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Important stepscountries may wish to take include to:

seek regional soluons in order to avoid unnecessary risks associated with transportaon of mercury waste;

address issues of ownership, liability and traceability; and

ensure that the rules and procedures of the Basel Convenon and/or relevant internaonal rules, standards and

guidelines are observed.

Export of mercury-added uorescent lamps for recycling (Philippines)

A mercury recycler from Japan and a collecon company from the Philippines established a cooperave

arrangement for the shipment of uorescent lamps for recycling. In order to avoid transport costs (and the

associated risks), the company is currently invesgang the commercializaon of a plant in the Philippines.