Best Available Techniques (BAT) and Limit Values

Assessments of technological developments:

Best available techniques (BAT) and limit values

Final Draft

Prepared by:

Katja Kraus (Chair, Germany)

Stefan Wenzel (Germany)

Grace Howland (Canada)

Ute Kutschera (Austria)

Stanislaw Hlawiczka (Poland)

André Peeters Weem (The Netherlands)

Chuck French (United States of America)

Submitted to the Task Force on Heavy Metals

UNECE Convention on Long-range Transboundary Air Pollution

June 14, 2006

Executive summary

1. The following overview of the most recent technological BAT developments in relation to annex III of the Protocol covers both new and existing stationary sources and is given for each source category as indicated in annex III. Additional information is given for emerging technologies. Techniques already described in annex III are not taken into account for this summary. Further information on techniques with regard to application, environmental performance etc., can be found in the respective chapters.
2. The primary sources of information for this document were the BAT reference documents from the European Integrated Pollution Prevention and Control Bureau (EIPPCB). Other sources of information included the United Nations Environment Program (UNEP) 2002 Global Mercury Assessment, and various technical reports from United States Environmental Protection Agency (U.S. EPA), Environment Canada, and the European Commission. References relevant to each chapter are provided at the end of the individual chapters. There may by other sources of information that were not considered.

Table 1:Overview on Most Recent Developments with BAT and other Emissions Control Techniques

Sector / BAT according to BREF documents and potential BAT from other references / Emerging Techniques
Combustion of fossil fuels in utility and industrial boilers / Stable combustion conditions (reduce peak emissions)
Wet FGD plus particulate matter (PM) control device (ESP or FF) (plus high dust SCR)
Injection of sorbent prior to FGD
Carbon filter bed filtration of flue gas
For low sulfur fuels (e.g. biomass):
FF
For combustion of coal:
IGCC / New designs of ESPs
Improving the liquid-to-gas ratio
Wet FGD Tower Design
Injection of activated carbon impregnated with additives
Low-NOx technologies (BAT for NOx-control)
Reburning (BAT for NOx-control)
Simultaneous control of sulfur dioxide, nitrogen oxides and Hg
Fuel cells
Biomass-fired IGCC
Primary iron and steel industry / Efficient capture and exhaust of emissions
Processing of ferrous metal ores
Increase the mercury rejection to the tailing
Sinter plants
Fine wet scrubbers or FF with lime addition
Exclusion of PM from last ESP field from recycling to the sinter strand
Recirculation of waste gas
Pelletisation plants
Scrubbing
Semi-dry desulfurization and subsequent PM removal
Blast furnaces
Hot stoves
Cast house PM removal
Basic oxygen furnaces:
Minimize the presence of mercury in the scrap by removing mercury-bearing components / Direct reduction/ smelting reduction (alternatives to the coke oven/BF route)
Blast furnaces
Continuous steelmaking
Basic oxygen steelmaking and casting
New reagents in the desulfurization process
Foaming techniques at pig iron pre-treatment and steel refining
Secondary iron and steel industry / Minimize the presence of mercury in the scrap by removing mercury-bearing components
Electric arc furnace
Direct off gas extraction
Capture and control of charging and tapping emissions, e.g., canopy hood and baghouse) / Electric arc furnace
Comelt EAF / Contiarc furnace / Direct reduction / Liquid iron
Iron foundries / Minimizing fugitive emissions
Cupola furnace melting of cast iron
Improve the thermal efficiency
Divided blast operation (2 rows of tuyères) for cold blast cupolas
Oxygen enrichment of the blast air
Minimize the blast-off periods for hot blast cupolas
Induction furnace melting of cast iron and steel
Increase furnace efficiency
Dry flue-gas cleaning
Rotary furnace melting of cast iron
Increase the melting efficiency
Post combustion
Dry PM removal
Primary and secondary non-ferrous metal industry / Minimize emissions from materials handling, storage and transfer
Sealed reactors and furnaces
Processes connected to a sulfuric acid plant:
Wet scrubber or wet ESP
Removal of mercury from off-gas
Activated carbon filter
Spray dry systems with downstream FF
Removal of mercury from sulfuric acid
Superlig Ion Exchange process
Potassium iodide process
Primary and secondary production of copper
Various processes depending on raw materials
FF (with lime injection)
Scrubbing (if necessary)
Secondary production of aluminium
Various processes depending on raw materials
FF or ceramic filter
Primary and secondary production of lead and zinc
Various processes depending on raw materials
FF /wet ESP /wet scrubbing (depending on process)
Production of gold
FF / wet ESP / scrubbing (depending on process)
Production of mercury
Phase out primary production of mercury
Stop surpluses re-entering the market
Production of mercury from secondary raw materials
Mercury scrubber (Boliden, thiosulphate etc). / Selenium filter
Odda chloride process
Primary and secondary production of copper
Bath smelting
ISA Smelt
hydro-metallurgical processes (e.g. leach-solvent extraction-electro-win (L:SX:EW) process)
Secondary production of aluminium
Reuse of filter PM
Catalytic filter bags
Primary and secondary production of lead and zinc
Leaching processes based on chloride
Injection of fine material
EZINEX process (direct treatment of EAF dusts)
Direct smelting
Lead sulfide process
BSN process using PM from EAF
Production of gold
'J' process
Gold production from pyrite concentrate
Production of mercury
Process with abatement of fine mercury particles
Cement industry / Dry process kiln with multi-stage preheating and precalcination / Fluidised bed cement manufacturing
Lower exhaust temperature
Adsorption on activated carbon
Glass industry / ESP or FF (with dry or semi-dry acid gas scrubbing)
Dry Injection FF/ Dry Lime Scrubber combination, or wet scrubber
Minimize downstream emissions / Plasma melter
Chlor-alkali industry / PARCOM decision 90/3 of 14 June 1990 (phase-out of the mercury process) was reviewed in 1999-2001 without any changes
Conversion to membrane cell technology
Non-asbestos diaphragm technology
Stop surplus of Hg from decommissioning re-entering the market
Minimizing emissions from handling, storage, treatment and disposal of mercury-contaminated wastes
Stringent work place practices to reduce emissions, including:

1. Use of specific equipment (e.g., smooth interior pipes, fixed covers, head space routed to ventilation system etc....
2. Preventive Operations (e.g., cool electroplate and decomposer before opening, keep mercury covered with aqueous liquid at temperature below its boiling point, gas stream cooling to remove mercury from hydrogen stream

Mist eliminators
Scrubbers
Adsorption on activated carbon and molecular sieves
Complete enclosure of the cell room
Municipal, medical and hazardous waste incineration / In some countries, no differentiation between municipal, hazardous and medical waste in terms of applied techniques or achievable emission limits.
Separate collection and treatment of mercury-containing wastes
Substitution of mercury in products
Sorbent injection
FGD
Carbon filter beds
Wet scrubber with additives
Selenium filters
Activated carbon injection prior to the ESP or FF
Activated carbon or coke filters
Selective catalytic reduction (SCR)
Co-incineration of waste and recovered fuel in cement kilns
Avoid Hg entering as an elevated component of the secondary fuel
BAT for cement kilns
Co- incineration of waste and recovered fuel in combustion installations
Avoid Hg entering as an elevated component of the secondary fuel
Gasification of the secondary fuel
Injection of activated carbon
BAT for combustion installations / Heavy metal evaporation process
Hydro-metallurgical treatment + vitrification
Municipal waste incineration
PECK combination process
Definition of Acronyms used in Table 1:
BATBest available techniques
BFBlast furnace
BOFBasic oxygen furnace
BREFBest available technique reference document
CFACirculating fluidized-bed absorber
EAFElectric arc furnace
ESPElectrostatic precipitator
FFFabric filter
FGDFlue gas desulfurization
IGCCIntegrated gasification combined-cycle
PMParticulate matter
SCRSelective Catalytic Reduction

1. The following overview of the most recent technological ELV developments in relation to annex V of the Protocol covers both new and existing stationary sources and is given for each source category as indicated in annex III. Additional information is given for source categories identified in annex II and heavy metals indicated in annex I of the Protocol for which no ELV is specified in annex V. The current ELVs of annex V are given for comparison, as well as emission levels associated with best available techniques (BAT) from the European BREF documents which are not considered as ELVs. Most sectors cover a wide range of installations with regard to technology and size, and the indicated ranges often comprise several techniques and/or size classes. ELVs for heavy metals are often given for a whole range of heavy metals, so the indicated values may not reflect an ELV for a single pollutant. Additionally, a combination of techniques might be necessary to achieve the indicated BAT associated emission levels. For further information, reference is made to the background information.
2. All values are expressed in mg/Nm³, except for the chlor-alkali industry, where values are expressed in g Hg/Mg Cl2 production capacity. All values refer to standard conditions (273.15 K, 101.3 kPa, dry gas) and do not cover start-up and shutdown periods.

Table 2:Overview on ELVs

Sector / Pollutant / ELVs
Combustion of fossil fuels in utility and industrial boilers (> 50 MW, solid and liquid fuels) / PM / Annex V50
ELVs in force (new installations)17-50
ELVs in force (existing installations)20-150
BAT (50 – 300 MW, new installations)5-20
BAT (50 – 300 MW, existing installations)5-30
BAT (> 300 MW, new installations)5-10
BAT (> 300 MW, existing installations)5-20
Cd / ELVs in force0.05-1.1
Pb / ELVs in force0.5-5
Hg / ELVs in force0.01-0.2
Primary iron and steel industry / PMsinter plants / Annex V50
ELVs in force20-150
BAT10-50
pellet plants / Annex V25
ELVs in force20-150
BAT< 10
blast furnace / Annex V50
ELVs in force6.8-150
BAT1-15
other processes / ELVs in force5-150
BAT5-30
Cd / ELVs in force0.05-0.2
Pb / ELVs in force0.5-5
Hg / ELVs in force0.05-0.2
Secondary iron and steel industry / PM EAF > 2.5 t / Annex V20
ELVs in force5-20
BAT< 5-15
other processes / ELVs in force20-50
Cd / ELVs in force0.05-0.2
Pb / ELVs in force0.5-5
Hg / ELVs in force0.05-0.2
Iron foundries / PM / ELVs in force2.3-50
BAT5-20
Cd / ELVs in force0.05-0.2
Pb / ELVs in force0.5-5
Hg / ELVs in force0.05-0.2
Primary and secondary non-ferrous metal industry / PM production of
copper and zinc / Annex V20
ELVs in force1-50
BAT1-5
production of lead / Annex V10
ELVs in force1-50
BAT1-5
production. of gold / ELVs in force1-50
BAT1-5
production of mercury / ELVs in force1-50
BAT1-5
other processes / ELVs in force5-50
Cd / ELVs in force0.05-0.2
Pb / ELVs in force0.5-5
Hg / ELVs in force0.05-0.2
Cement industry / PM / Annex V50
ELVs in force15-150
BAT20-30
Cd / ELVs in force0.05-0.2
Pb / ELVs in force0.5-5
Hg / ELVs in force0.05-0.2
Glass industry / PM / ELVs in force5-50
BAT5-30
Cd / ELVs in force0.05-5
Pb / Annex V5
ELVs in force0.5-5
BAT<5
Hg / ELVs in force0.05-0.2
Chlor-alkali industry / Hgnew
installations / Annex V0.01
ELVs in force0.0-0.01
existing
installations / ELVs in force (legally binding phase out of mercury process) 1 -5.3
BAT (total emissions)(phase out of mercury process) 0.21-0.32
Municipal, medical and hazardous waste incineration / PM municipal waste
incineration > 3t/h / Annex V25
ELVs in force5-50
BAT1-5
medical waste
incineration > 1t/h / Annex V10
ELVs in force5-30
BAT1-5
hazardous waste
incineration > 1t/h / Annex V10
ELVs in force2.4-57
BAT1-5
co-incineration / ELVs in force10-20
Cd municipal waste
incineration > 3t/h / ELVs in force0.03-0.2
BAT0.005-0.05
medical waste
incineration > 1t/h / ELVs in force0.028-0.2
BAT0.005-0.05
hazardous waste
incineration > 1t/h / ELVs in force0.05-0.5
BAT0.005-0.05
co-incineration / ELVs in force0.05
Pb municipal waste
incineration > 3t/h / ELVs in force0.31-5
BAT0.005-0.5
medical waste
incineration > 1t/h / ELVs in force0.05-5
BAT0.005-0.5
hazardous waste
incineration > 1t/h / ELVs in force0.5-5
BAT0.005-0.5
co-incineration / ELVs in force0.5
Hg municipal waste
incineration > 3t/h / Annex V0.08
ELVs in force0.02-0.2
BAT0.001-0.02
medical waste
incineration > 1t/h / ELVs in force0.02-0.39
BAT0.001-0.02
hazardous waste
incineration > 1t/h / Annex V0.005-0.2
ELVs in force0.001-0.02
BAT
co-incineration / ELVs in force0.03-0.05

Table of contents

INTRODUCTION

COMBUSTION OF FOSSIL FUELS IN UTILITY AND INDUSTRIAL BOILERS

PRIMARY IRON AND STEEL INDUSTRY

SECONDARY IRON AND STEEL INDUSTRY

IRON FOUNDRIES

PRIMARY AND SECONDARY NON-FERROUS METAL INDUSTRY

CEMENT INDUSTRY

GLASS INDUSTRY

CHLOR-ALKALI INDUSTRY

MUNICIPAL, MEDICAL AND HAZARDOUS WASTE INCINERATION

INTRODUCTION

1. The Task Force on Heavy Metals reviewed technological developments with regard to emissions from stationary sources for those heavy metals (HM) listed in annex I to the Protocol. This report compiles background information on technological developments for each source category of annex II to the Protocol, including:

-a compilation of recent developments in best available techniques (BAT) in relation to annex III to the Protocol;

-a compilation of current emission limit values (ELVs) in relation to annex V to the Protocol as well as for source categories identified in annex II and HM indicated in annex I for which no ELV is specified in annex V.

1. The report is structured according to the technical information given in annex III to the Protocol. The following table gives an overview of the chapters of the report and their correspondence to the sector description and technical information in annex III and the source categories of annex II to the Protocol.

Table 3:Coverage of sectors in this report

Sector (chapter of the report) / Technical information according to annex III to the Protocol / Source categories according to annex II to the Protocol
Combustion of fossil fuels in utility and industrial boilers / Combustion of fossil fuels in utility and industrial boilers: coal and fuel oil fired boilers, not including gas turbines and stationary engines, and not including the use of waste as a fuel, are considered. / 1: Combustion installations with a net rated thermal input exceeding 50 MW
Primary iron and steel industry / Primary iron and steel industry: the processing of ferrous metal ores together with the primary iron and steel industry are considered. The production of mercury and gold as well as the roasting and sintering of non-ferrous metal ores are regarded within the primary and secondary non-ferrous metal industry. / 2: Metal ore (including sulphide ore) or concentrate roasting or sintering installations with a capacity exceeding 150 tonnes of sinter per day for ferrous ore or concentrate, and 30 tonnes of sinter per day for the roasting of copper, lead or zinc, or any gold and mercury ore treatment.
Secondary iron and steel industry / Secondary iron and steel industry: the secondary iron and steel industry including electric arc furnaces (EAF) are considered. / 3: Installations for the production of pig-iron or steel (primary or secondary fusion, including electric arc furnaces) including continuous casting, with a capacity exceeding 2.5 tonnes per hour.
Iron foundries / Iron foundries: iron foundries, not including steel and temper foundries, are considered. / 4: Ferrous metal foundries with a production capacity exceeding 20 tonnes per day.
Primary and secondary non-ferrous metal industry / Primary and secondary non-ferrous metal industry: the processing of non-ferrous metals and their ores is considered. / 5: Installations for the production of copper, lead and zinc from ore, concentrates or secondary raw materials by metallurgical processes with a capacity exceeding 30 tonnes of metal per day for primary installations and 15 tonnes of metal per day for secondary installations, or for any primary production of mercury.
6: Installations for the smelting (refining, foundry casting, etc.), including the alloying, of copper, lead and zinc, including recovered products, with a melting capacity exceeding 4 tonnes per day for lead or 20 tonnes per day for copper and zinc.
Cement industry / Cement industry: the production of cement clinker in fossil fuel fired kilns, not including the use of waste as a fuel, is considered. / 7: Installations for the production of cement clinker in rotary kilns with a production capacity exceeding 500 tonnes per day or in other furnaces with a production capacity exceeding 50 tonnes per day.
Glass industry / Glass industry: the production of glass using lead in the process, including the recycling of lead containing glass, is considered. / 8: Installations for the manufacture of glass using lead in the process with a melting capacity exceeding 20 tonnes per day.
Chlor-alkali industry / Chlor-alkali industry: the chlor-alkali production by the mercury, diaphragm and membrane cell electrolysis process is considered. / 9: Installations for chlor-alkali production by electrolysis using the mercury cell process..
Municipal, medical and hazardous waste incineration / Municipal, medical and hazardous waste incineration: the incineration of municipal, medical and hazardous waste is considered. / 10: Installations for the incineration of hazardous or medical waste with a capacity exceeding 1 tonne per hour, or for the co-incineration of hazardous or medical waste specified in accordance with national legislation.
11: Installations for the incineration of municipal waste with a capacity exceeding 3 tonnes per hour, or for the co-incineration of municipal waste specified in accordance with national legislation.

1. The following acronyms are used throughout the document:

BATBest available techniques

BFBlast furnace

BOFBasic oxygen furnace

BREFBest available technique reference document

CFACirculating fluidized-bed absorber

EAFElectric arc furnace

EIPPCBEuropean Integrated Pollution Prevention and control Bureau

ELVEmission limit values

ESPElectrostatic precipitator

FFFabric filter

FGDFlue gas desulfurization

IGCC Integrated gasification combined-cycle

PMParticulate matter

SCR Selective Catalytic Reduction

1. The primary sources of information for this document were the BAT reference documents from the European Integrated Pollution Prevention and control Bureau (EIPPCB). Other sources of information included the United Nations Environment Program (UNEP) 2002 Global Mercury Assessment, and various technical reports from the US Environmental Protection Agency (US EPA), Environment Canada, and the European Commission. References relevant to each chapter are provided at the end of the individual chapters. There may by other sources of information that were not considered.

COMBUSTION OF FOSSIL FUELS IN UTILITY AND INDUSTRIAL BOILERS

Background

1. This category covers the combustion of fossil fuels in utility and industrial boilers. Annex II of the Protocol limits the coverage to combustion installations with a net rated thermal input exceeding 50 Megawatts (MW). According to Annex III, Best Available Techniques (BATs) are considered for coal and fuel oil fired boilers.
2. The combustion of biomass and peat are not currently taken into account in annex III but may be a relevant source of heavy metal emissions. Therefore, additional information is given for these installations. The co-incineration of waste in combustion installations is treated within the category municipal, medical and hazardous waste incineration.
3. According to Annex III, BAT to reduce emissions of heavy metals, except mercury, include the reduction in fuel use and the combustion of natural gas or alternative fuels with a low heavy metal content, the use of electrostatic precipitators or fabric filters. Further emission reduction may be achieved by integrated gasification combined-cycle (IGCC) power plant technology, the beneficiation (washing or bio-treatment) of coal, and the application of techniques to reduce emissions of nitrogen oxides, sulphur dioxide and particulates. No BAT for mercury removal is identified in Annex III.

Best Available Techniques based on the EIPPCB BAT reference (BREF) document and potential BATs from other recent publications