COMMISSION IMPLEMENTING DECISION (EU) 2016/1032
of 13 June 2016
establishing best available techniques (BAT) conclusions, under Directive 2010/75/EU of the European Parliament and of the Council, for the non-ferrous metals industries
(notified under document C(2016) 3563)
(Text with EEA relevance)
Article 1
Article 2
ANNEX
SCOPE
Reference document |
Subject |
Energy Efficiency (ENE) |
General aspects of energy efficiency |
Common Waste Water and Waste Gas Treatment/Management Systems in the Chemical Sector (CWW) |
Waste water treatment techniques to reduce emissions of metals to water |
Large Volume Inorganic Chemicals-Ammonia, Acids and Fertilisers (LVIC-AAF) |
Sulphuric acid production |
Industrial Cooling Systems (ICS) |
Indirect cooling with water and/or air |
Emissions from Storage (EFS) |
Storage and handling of materials |
Economics and Cross-media Effects (ECM) |
Economics and cross-media effects of techniques |
Monitoring of Emissions to Air and Water from IED installations (ROM) |
Monitoring of emissions to air and water |
Waste Treatments Industries (WT) |
Waste handling and treatment |
Large Combustion Plants (LCP) |
Combustion plants generating steam and/or electricity |
Surface Treatment Using Organic Solvents (STS) |
Non-acid pickling |
Surface Treatment of Metals and Plastics (STM) |
Acid pickling |
DEFINITIONS
Term used |
Definition |
New plant |
A plant first permitted at the site of the installation following the publication of these BAT conclusions or a complete replacement of a plant on the existing foundations of the installation following the publication of these BAT conclusions |
Existing plant |
A plant that is not a new plant |
Major upgrade |
A major change in the design or technology of a plant and with major adjustments or replacements of the process units and associated equipment |
Primary emissions |
Emissions directly vented from the furnaces that are not spread to the areas surrounding the furnaces |
Secondary emissions |
Emissions escaping from the furnace lining or during operations such as charging or tapping and which are captured with a hood or enclosure (such as doghouse) |
Primary production |
Production of metals using ores and concentrates |
Secondary production |
Production of metals using residues and/or scraps, including remelting and alloying processes |
Continuous measurement |
Measurement using an ‘automated measuring system’ permanently installed on site for the continuous monitoring of emissions |
Periodic measurement |
Determination of a measurand (a particular quantity subject to measurement) at specified time intervals using manual or automated methods |
GENERAL CONSIDERATIONS
Daily average |
Average over a period of 24 hours of valid half-hourly or hourly averages obtained by continuous measurements |
Average over the sampling period |
Average value of three consecutive measurements of at least 30 minutes each, unless otherwise stated(1) |
Daily average |
Average over a sampling period of 24 hours taken as a flow-proportional composite sample (or as a time-proportional composite sample provided that sufficient flow stability is demonstrated)(2) |
ACRONYMS
Term |
Meaning |
BaP |
Benzo[a]pyrene |
ESP |
Electrostatic precipitator |
I-TEQ |
International toxic equivalency derived by applying international toxic equivalence factors, as defined in Annex VI, part 2 of Directive 2010/75/EU |
NOX |
The sum of nitrogen monoxide (NO) and nitrogen dioxide (NO2), expressed as NO2 |
PCDD/F |
Polychlorinated dibenzo-p-dioxins and dibenzofurans (17 congeners) |
PAH |
Polycyclic aromatic hydrocarbons |
TVOC |
Total volatile organic carbon; total volatile organic compounds which are measured by a flame ionisation detector (FID) and expressed as total carbon |
VOC |
Volatile organic compounds as defined in Article 3(45) of Directive 2010/75/EU |
1.1. GENERAL BAT CONCLUSIONS
1.1.1.
1.1.2.
|
Technique |
Applicability |
a |
Energy efficiency management system (e.g. ISO 50001) |
Generally applicable |
b |
Regenerative or recuperative burners |
Generally applicable |
c |
Heat recovery (e.g. steam, hot water, hot air) from waste process heat |
Only applicable for pyrometallurgical processes |
d |
Regenerative thermal oxidiser |
Only applicable when the abatement of a combustible pollutant is required |
e |
Preheat the furnace charge, combustion air or fuel using the heat recovered from hot gases from the melting stage |
Only applicable for roasting or smelting of sulphide ore/concentrate and for other pyrometallurgical processes |
f |
Raise the temperature of the leaching liquors using steam or hot water from waste heat recovery |
Only applicable for alumina or hydrometallurgical processes |
g |
Use hot gases from the launder as preheated combustion air |
Only applicable for pyrometallurgical processes |
h |
Use oxygen-enriched air or pure oxygen in the burners to reduce energy consumption by allowing autogenous smelting or the complete combustion of carbonaceous material |
Only applicable for furnaces that use raw materials containing sulphur or carbon |
i |
Dry concentrates and wet raw materials at low temperatures |
Only applicable when drying is performed |
j |
Recover the chemical energy content of the carbon monoxide produced in an electric or shaft/blast furnace by using the exhaust gases as a fuel, after the removal of metals, in other production processes or to produce steam/hot water or electricity |
Only applicable to exhaust gases with a CO content > 10 vol-%. Applicability is also influenced by the composition of the exhaust gas and the unavailability of a continuous flow (i.e. batch processes) |
k |
Recirculate the flue-gas back through an oxy-fuel burner to recover the energy contained in the total organic carbon present |
Generally applicable |
l |
Suitable insulation for high temperature equipment such as steam and hot water pipes |
Generally applicable |
m |
Use the heat generated from the production of sulphuric acid from sulphur dioxide to preheat gas directed to the sulphuric acid plant or to generate steam and/or hot water |
Only applicable for non-ferrous metals plants including sulphuric acid or liquid SO2 production |
n |
Use high efficiency electric motors equipped with variable-frequency drive, for equipment such as fans |
Generally applicable |
o |
Use control systems that automatically activate the air extraction system or adjust the extraction rate depending on actual emissions |
Generally applicable |
1.1.3.
|
Technique |
a |
Inspect and select input materials according to the process and the abatement techniques applied |
b |
Good mixing of the feed materials to achieve optimum conversion efficiency and reduce emissions and rejects |
c |
Feed weighing and metering systems |
d |
Processors to control material feed rate, critical process parameters and conditions including the alarm, combustion conditions and gas additions |
e |
On-line monitoring of the furnace temperature, furnace pressure and gas flow |
f |
Monitor the critical process parameters of the air emission abatement plant such as gas temperature, reagent metering, pressure drop, ESP current and voltage, scrubbing liquid flow and pH and gaseous components (e.g. O2, CO, VOC) |
g |
Control dust and mercury in the exhaust gas before transfer to the sulphuric acid plant for plants including sulphuric acid or liquid SO2 production |
h |
On-line monitoring of vibrations to detect blockages and possible equipment failure |
i |
On-line monitoring of the current, voltage and electrical contact temperatures in electrolytic processes |
j |
Temperature monitoring and control at melting and smelting furnaces to prevent the generation of metal and metal oxide fumes through overheating |
k |
Processor to control the reagents feeding and the performance of the waste water treatment plant, through on-line monitoring of temperature, turbidity, pH, conductivity and flow |
1.1.4.
1.1.4.1.
1.1.4.2.
|
Technique |
||||
a |
Enclosed buildings or silos/bins for storing dust-forming materials such as concentrates, fluxes and fine materials |
||||
b |
Covered storage of non-dust-forming materials such as concentrates, fluxes, solid fuels, bulk materials and coke and secondary materials that contain water-soluble organic compounds |
||||
c |
Sealed packaging of dust-forming materials or secondary materials that contain water-soluble organic compounds |
||||
d |
Covered bays for storing material which has been pelletised or agglomerated |
||||
e |
Use water sprays and fog sprays with or without additives such as latex for dust-forming materials |
||||
f |
Dust/gas extraction devices placed at the transfer and tipping points for dust-forming materials |
||||
g |
Certified pressure vessels for storing chlorine gas or mixtures that contain chlorine |
||||
h |
Tank construction materials that are resistant to the contained materials |
||||
i |
Reliable leak detection systems and display of tank’s level, with an alarm to prevent overfills |
||||
j |
Store reactive materials in double-walled tanks or tanks placed in chemical-resistant bunds of the same capacity and use a storage area that is impermeable and resistant to the material stored |
||||
k |
Design storage areas so that
|
||||
l |
Use inert gas blanketing for the storage of materials that react with air |
||||
m |
Collect and treat emissions from storage with an abatement system designed to treat the compounds stored. Collect and treat before discharge any water that washes dust away. |
||||
n |
Regular cleaning of the storage area and, when needed, moistening with water |
||||
o |
Place the longitudinal axis of the heap parallel to the prevailing wind direction in the case of outdoor storage |
||||
p |
Protective planting, windbreak fences or upwind mounts to lower the wind velocity in the case of outdoor storage |
||||
q |
One heap instead of several where feasible in the case of outdoor storage |
||||
r |
Use oil and solid interceptors for the drainage of open outdoor storage areas. Use of concreted areas that have kerbs or other containment devices for the storage of material that can release oil, such as swarf |
|
Technique |
a |
Enclosed conveyors or pneumatic systems to transfer and handle dust-forming concentrates and fluxes and fine-grained material |
b |
Covered conveyors to handle non-dust-forming solid materials |
c |
Extraction of dust from delivery points, silo vents, pneumatic transfer systems and conveyor transfer points, and connection to a filtration system (for dust-forming materials) |
d |
Closed bags or drums to handle materials with dispersible or water-soluble components |
e |
Suitable containers to handle pelletised materials |
f |
Sprinkling to moisten the materials at handling points |
g |
Minimise transport distances |
h |
Reduce the drop height of conveyor belts, mechanical shovels or grabs |
i |
Adjust the speed of open belt conveyors (< 3,5 m/s) |
j |
Minimise the speed of descent or free fall height of the materials |
k |
Place transfer conveyors and pipelines in safe, open areas above ground so that leaks can be detected quickly and damage from vehicles and other equipment can be prevented. If buried pipelines are used for non-hazardous materials, document and mark their course and adopt safe excavation systems |
l |
Automatic resealing of delivery connections for handling liquid and liquefied gas |
m |
Back-vent displaced gases to the delivery vehicle to reduce emissions of VOC |
n |
Wash wheels and chassis of vehicles used to deliver or handle dusty materials |
o |
Use planned campaigns for road sweeping |
p |
Segregate incompatible materials (e.g. oxidising agents and organic materials) |
q |
Minimise material transfers between processes |
1.1.4.3.
|
Technique |
Applicability |
a |
Thermal or mechanical pretreatment of secondary raw material to minimise organic contamination of the furnace feed |
Generally applicable |
b |
Use a closed furnace with a properly designed dedusting system or seal the furnace and other process units with an adequate vent system |
The applicability may be restricted by safety constraints (e.g. type/design of the furnace, risk of explosion) |
c |
Use a secondary hood for furnace operations such as charging and tapping |
The applicability may be restricted by safety constraints (e.g. type/design of the furnace, risk of explosion) |
d |
Dust or fume collection where dusty material transfers take place (e.g. furnace charging and tapping points, covered launders) |
Generally applicable |
e |
Optimise the design and operation of hooding and ductwork to capture fumes arising from the feed port and from hot metal, matte or slag tapping and transfers in covered launders |
For existing plants, the applicability may be limited by space and plant configuration restrictions |
f |
Furnace/reactor enclosures such as ‘house-in-house’ or ‘doghouse’ for tapping and charging operations |
For existing plants, the applicability may be limited by space and plant configuration restrictions |
g |
Optimise the off-gas flow from the furnace through computerised fluid dynamics studies and tracers |
Generally applicable |
h |
Charging systems for semi-closed furnaces to add raw materials in small amounts |
Generally applicable |
i |
Treat the collected emissions in an adequate abatement system |
Generally applicable |
1.1.5.
Parameter |
Monitoring associated with |
Minimum monitoring frequency |
Standard(s) |
||
Dust(4) |
Copper: BAT 38, BAT 39, BAT 40, BAT 43, BAT 44, BAT 45 Aluminium: BAT 56, BAT 58, BAT 59, BAT 60, BAT 61, BAT 67, BAT 81, BAT 88 Lead, Tin: BAT 94, BAT 96, BAT 97 Zinc, Cadmium: BAT 119, BAT 122 Precious metals: BAT 140 Ferro-alloys: BAT 155, BAT 156, BAT 157, BAT 158 Nickel, Cobalt: BAT 171 Other non-ferrous metals: emissions from production stages such as raw material pretreatment, charging, smelting, melting and tapping |
Continuous(3) |
EN 13284-2 |
||
Copper: BAT 37, BAT 38, BAT 40, BAT 41, BAT 42, BAT 43, BAT 44, BAT 45 Aluminium: BAT 56, BAT 58, BAT 59, BAT 60, BAT 61, BAT 66, BAT 67, BAT 68, BAT 80, BAT 81, BAT 82, BAT 88 Lead, Tin: BAT 94, BAT 95, BAT 96, BAT 97 Zinc, Cadmium: BAT 113, BAT 119, BAT 121, BAT 122, BAT 128, BAT 132 Precious metals: BAT 140 Ferro-alloys: BAT 154, BAT 155, BAT 156, BAT 157, BAT 158 Nickel, Cobalt: BAT 171 Carbon/graphite: BAT 178, BAT 179, BAT 180, BAT 181 Other non-ferrous metals: emissions from production stages such as raw material pretreatment, charging, smelting, melting and tapping |
Once per year(3) |
EN 13284-1 |
|||
Antimony and its compounds, expressed as Sb |
Lead, Tin: BAT 96, BAT 97 |
Once per year |
EN 14385 |
||
Arsenic and its compounds, expressed as As |
Copper: BAT 37, BAT 38, BAT 39, BAT 40, BAT 42, BAT 43, BAT 44, BAT 45 Lead, Tin: BAT 96, BAT 97 Zinc: BAT 122 |
Once per year |
EN 14385 |
||
Cadmium and its compounds, expressed as Cd |
Copper: BAT 37, BAT 38, BAT 39, BAT 40, BAT 41, BAT 42, BAT 43, BAT 44, BAT 45 Lead, Tin: BAT 94, BAT 95, BAT 96, BAT 97 Zinc, Cadmium: BAT 122, BAT 132 Ferro-alloys: BAT 156 |
Once per year |
EN 14385 |
||
Chromium (VI) |
Ferro-alloys: BAT 156 |
Once per year |
No EN standard available |
||
Copper and its compounds, expressed as Cu |
Copper: BAT 37, BAT 38, BAT 39, BAT 40, BAT 42, BAT 43, BAT 44, BAT 45 Lead, Tin: BAT 96, BAT 97 |
Once per year |
EN 14385 |
||
Nickel and its compounds, expressed as Ni |
Nickel, Cobalt: BAT 172, BAT 173 |
Once per year |
EN 14385 |
||
Lead and its compounds, expressed as Pb |
Copper: BAT 37, BAT 38, BAT 39, BAT 40, BAT 41, BAT 42, BAT 43, BAT 44, BAT 45 Lead, Tin: BAT 94, BAT 95, BAT 96, BAT 97 Ferro-alloys: BAT 156 |
Once per year |
EN 14385 |
||
Thallium and its compounds, expressed as Tl |
Ferro-alloys: BAT 156 |
Once per year |
EN 14385 |
||
Zinc and its compounds, expressed as Zn |
Zinc, Cadmium: BAT 113, BAT 114, BAT 119, BAT 121, BAT 122, BAT 128, BAT 132 |
Once per year |
EN 14385 |
||
Other metals, if relevant(5) |
Copper: BAT 37, BAT 38, BAT 39, BAT 40, BAT 41, BAT 42, BAT 43, BAT 44, BAT 45 Lead, Tin: BAT 94, BAT 95, BAT 96, BAT 97 Zinc, Cadmium: BAT 113, BAT 119, BAT 121, BAT 122, BAT 128, BAT 132 Precious metals: BAT 140 Ferro-alloys: BAT 154, BAT 155, BAT 156, BAT 157, BAT 158 Nickel, Cobalt: BAT 171 Other non-ferrous metals |
Once per year |
EN 14385 |
||
Mercury and its compounds, expressed as Hg |
Copper, Aluminium, Lead, Tin, Zinc, Cadmium, Ferro-alloys, Nickel, Cobalt, Other non-ferrous metals: BAT 11 |
Continuous or once per year(3) |
EN 14884 EN 13211 |
||
SO2 |
Copper: BAT 49 Aluminium: BAT 60, BAT 69 Lead, Tin: BAT 100 Precious metals: BAT 142, BAT 143 Nickel, Cobalt: BAT 174 Other non-ferrous metals (8) (9) |
Continuous or once per year(3) (6) |
EN 14791 |
||
Zinc, Cadmium: BAT 120 |
Continuous |
||||
Carbon/graphite: BAT 182 |
Once per year |
||||
NOX, expressed as NO2 |
Copper, Aluminium, Lead, Tin, FeSi, Si (pyrometallurgical processes): BAT 13 Precious metals: BAT 141 Other non-ferrous metals (9) |
Continuous or once per year(3) |
EN 14792 |
||
Carbon/graphite |
Once per year |
||||
TVOC |
Copper: BAT 46 Aluminium: BAT 83 Lead, Tin: BAT 98 Zinc, Cadmium: BAT 123 Other non-ferrous metals (10) |
Continuous or once per year(3) |
EN 12619 |
||
Ferro-alloys: BAT 160 Carbon/graphite: BAT 183 |
Once per year |
||||
Formaldehyde |
Carbon/graphite: BAT 183 |
Once per year |
No EN standard available |
||
Phenol |
Carbon/graphite: BAT 183 |
Once per year |
No EN standard available |
||
PCDD/F |
Copper: BAT 48 Aluminium: BAT 83 Lead, Tin: BAT 99 Zinc, Cadmium: BAT 123 Precious metals: BAT 146 Ferro-alloys: BAT 159 Other non-ferrous metals (7) (9) |
Once per year |
EN 1948 parts 1, 2 and 3 |
||
H2SO4 |
Copper: BAT 50 Zinc, Cadmium: BAT 114 |
Once per year |
No EN standard available |
||
NH3 |
Aluminium: BAT 89 Precious metals: BAT 145 Nickel, Cobalt: BAT 175 |
Once per year |
No EN standard available |
||
Benzo-[a]-pyrene |
Aluminium: BAT 59, BAT 60, BAT 61 Ferro-alloys: BAT 160 Carbon/graphite: BAT 178, BAT 179, BAT 180, BAT 181 |
Once per year |
ISO 11338-1 ISO 11338-2 |
||
Gaseous fluorides, expressed as HF |
Aluminium: BAT 60, BAT 61, BAT 67 |
Continuous(3) |
ISO 15713 |
||
Aluminium: BAT 60, BAT 67, BAT 84 Zinc, Cadmium: BAT 124 |
Once per year(3) |
||||
Total fluorides |
Aluminium: BAT 60, BAT 67 |
Once per year |
No EN standard available |
||
Gaseous chlorides, expressed as HCl |
Aluminium: BAT 84 |
Continuous or once per year(3) |
EN 1911 |
||
Zinc, Cadmium: BAT 124 Precious metals: BAT 144 |
Once per year |
||||
Cl2 |
Aluminium: BAT 84 Precious metals: BAT 144 Nickel, Cobalt: BAT 172 |
Once per year |
No EN standard available |
||
H2S |
Aluminium: BAT 89 |
Once per year |
No EN standard available |
||
PH3 |
Aluminium: BAT 89 |
Once per year |
No EN standard available |
||
Sum of AsH3 and SbH3 |
Zinc, Cadmium: BAT 114 |
Once per year |
No EN standard available |
||
|
1.1.6.
|
Technique |
a |
Use raw materials with a low mercury content, including by cooperating with providers in order to remove mercury from secondary materials. |
b |
Use adsorbents (e.g. activated carbon, selenium) in combination with dust filtration(11) |
Parameter |
BAT-AEL (mg/Nm3)(12) (13) |
Mercury and its compounds, expressed as Hg |
0,01-0,05 |
1.1.7.
1.1.8.
|
Technique(14) |
a |
Low-NOX burners |
b |
Oxy-fuel burners |
c |
Flue-gas recirculation (back through the burner to reduce the temperature of the flame) in the case of oxy-fuel burners |
1.1.9.
|
Technique |
Applicability |
a |
Measure the amount of fresh water used and the amount of waste water discharged |
Generally applicable |
b |
Reuse waste water from cleaning operations (including anode and cathode rinse water) and spills in the same process |
Generally applicable |
c |
Reuse weak acid streams generated in a wet ESP and wet scrubbers |
Applicability may be restricted depending on the metal and solid content of the waste water |
d |
Reuse waste water from slag granulation |
Applicability may be restricted depending on the metal and solid content of the waste water |
e |
Reuse surface run-off water |
Generally applicable |
f |
Use a closed circuit cooling system |
Applicability may be restricted when a low temperature is required for process reasons |
g |
Reuse treated water from the waste water treatment plant |
Applicability may be restricted by the salt content |
Parameter |
Applicable for the production of(16) |
Standard(s) |
Mercury (Hg) |
Copper, Lead, Tin, Zinc, Cadmium, Precious metals, Ferro-alloys, Nickel, Cobalt, and other non-ferrous metals |
EN ISO 17852, EN ISO 12846 |
Iron (Fe) |
Copper, Lead, Tin, Zinc, Cadmium, Precious metals, Ferro-alloys, Nickel, Cobalt, and other non-ferrous metals |
EN ISO 11885 EN ISO 15586 EN ISO 17294-2 |
Arsenic (As) |
Copper, Lead, Tin, Zinc, Cadmium, Precious metals, Ferro-alloys, Nickel, and Cobalt |
|
Cadmium (Cd) |
||
Copper (Cu) |
||
Nickel (Ni) |
||
Lead (Pb) |
||
Zinc (Zn) |
||
Silver (Ag) |
Precious metals |
|
Aluminium (Al) |
Aluminium |
|
Cobalt (Co) |
Nickel, and Cobalt |
|
Chromium total (Cr) |
Ferro-alloys |
|
Chromium(VI) (Cr(VI)) |
Ferro-alloys |
EN ISO 10304-3 EN ISO 23913 |
Antimony (Sb) |
Copper, Lead, and Tin |
EN ISO 11885 EN ISO 15586 EN ISO 17294-2 |
Tin (Sn) |
Copper, Lead, and Tin |
|
Other metals, if relevant(17) |
Aluminium, Ferro-alloys, and other non-ferrous metals |
|
Sulphate (SO4 2-) |
Copper, Lead, Tin, Zinc, Cadmium, Precious metals, Nickel, Cobalt, and other non-ferrous metals |
EN ISO 10304-1 |
Fluoride (F-) |
Primary aluminium |
|
Total suspended solids (TSS) |
Aluminium |
EN 872 |
|
Technique(18) |
Applicability |
a |
Chemical precipitation |
Generally applicable |
b |
Sedimentation |
Generally applicable |
c |
Filtration |
Generally applicable |
d |
Flotation |
Generally applicable |
e |
Ultrafiltration |
Only applicable to specific streams in non-ferrous metals production |
f |
Activated carbon filtration |
Generally applicable |
g |
Reverse osmosis |
Only applicable to specific streams in non-ferrous metals production |
BAT-associated emission levels
BAT-AEL (mg/l) (daily average) |
||||||||
Parameter |
Production of |
|||||||
Copper |
Lead and/or Tin |
Zinc and/or Cadmium |
Precious metals |
Nickel and/or Cobalt |
Ferro-alloys |
|||
Silver (Ag) |
NR |
≤ 0,6 |
NR |
|||||
Arsenic (As) |
≤ 0,1(19) |
≤ 0,1 |
≤ 0,1 |
≤ 0,1 |
≤ 0,3 |
≤ 0,1 |
||
Cadmium (Cd) |
0,02–0,1 |
≤ 0,1 |
≤ 0,1 |
≤ 0,05 |
≤ 0,1 |
≤ 0,05 |
||
Cobalt (Co) |
NR |
≤ 0,1 |
NR |
0,1-0,5 |
NR |
|||
Chromium total (Cr) |
NR |
≤ 0,2 |
||||||
Chromium (VI) (Cr(VI)) |
NR |
≤ 0,05 |
||||||
Copper (Cu) |
0,05-0,5 |
≤ 0,2 |
≤ 0,1 |
≤ 0,3 |
≤ 0,5 |
≤ 0,5 |
||
Mercury (Hg) |
0,005–0,02 |
≤ 0,05 |
≤ 0,05 |
≤ 0,05 |
≤ 0,05 |
≤ 0,05 |
||
Nickel (Ni) |
≤ 0,5 |
≤ 0,5 |
≤ 0,1 |
≤ 0,5 |
≤ 2 |
≤ 2 |
||
Lead (Pb) |
≤ 0,5 |
≤ 0,5 |
≤ 0,2 |
≤ 0,5 |
≤ 0,5 |
≤ 0,2 |
||
Zinc (Zn) |
≤ 1 |
≤ 1 |
≤ 1 |
≤ 0,4 |
≤ 1 |
≤ 1 |
||
|
1.1.10.
|
Technique |
a |
Use embankments to screen the source of noise |
b |
Enclose noisy plants or components in sound-absorbing structures |
c |
Use anti-vibration supports and interconnections for equipment |
d |
Orientation of noise-emitting machinery |
e |
Change the frequency of the sound |
1.1.11.
|
Technique |
Applicability |
a |
Appropriate storage and handling of odorous materials |
Generally applicable |
b |
Minimise the use of odorous materials |
Generally applicable |
c |
Careful design, operation and maintenance of any equipment that could generate odour emissions |
Generally applicable |
d |
Afterburner or filtration techniques, including biofilters |
Applicable only in limited cases (e.g. in the impregnation stage during speciality production in the carbon and graphite sector) |
1.2. BAT CONCLUSIONS FOR COPPER PRODUCTION
1.2.1.
|
Technique |
a |
Manual separation of large visible constituents |
b |
Magnetic separation of ferrous metals |
c |
Optical or eddy current separation of aluminium |
d |
Relative density separation of different metallic and non-metallic constituents (using a fluid with a different density or air) |
1.2.2.
|
Technique |
Applicability |
a |
Optimise the use of the energy contained in the concentrate using a flash smelting furnace |
Only applicable for new plants and for major upgrades of existing plants |
b |
Use the hot process gases from the melting stages to heat up the furnace charge |
Only applicable to shaft furnaces |
c |
Cover the concentrates during transport and storage |
Generally applicable |
d |
Use the excess heat produced during the primary smelting or converting stages to melt secondary materials containing copper |
Generally applicable |
e |
Use the heat in the gases from anode furnaces in a cascade for other processes such as drying |
Generally applicable |
|
Technique |
Applicability |
a |
Reduce the water content of the feed material |
Applicability is limited when the moisture content of the materials is used as a technique to reduce diffuse emissions |
b |
Produce steam by recovering excess heat from the smelting furnace to heat up the electrolyte in refineries and/or to produce electricity in a co-generation installation |
Applicable if an economically viable demand of steam exists |
c |
Melt scraps using the excess heat that is produced during the smelting or converting process |
Generally applicable |
d |
Holding furnace between processing stages |
Only applicable for batch-wise operated smelters where a buffer capacity of molten material is required |
e |
Preheat the furnace charge using the hot process gases from the melting stages |
Only applicable to shaft furnaces |
|
Technique |
Applicability |
a |
Apply insulation and covers to electrolysis tanks |
Generally applicable |
b |
Addition of surfactants to the electrowinning cells |
Generally applicable |
c |
Improved cell design for lower energy consumption by optimisation of the following parameters: space between anode and cathode, anode geometry, current density, electrolyte composition and temperature |
Only applicable for new plants and for major upgrades of existing plants |
d |
Use of stainless steel cathode blanks |
Only applicable for new plants and for major upgrades of existing plants |
e |
Automatic cathode/anode changes to achieve an accurate placement of the electrodes into the cell |
Only applicable for new plants and for major upgrades of existing plants |
f |
Short circuit detection and quality control to ensure that electrodes are straight and flat and that the anode is exact in weight |
Generally applicable |
1.2.3.
1.2.3.1.
|
Technique |
Applicability |
a |
Use enclosed conveyers or pneumatic transfer systems for dusty materials |
Generally applicable |
b |
Carry out activities with dusty materials such as mixing in an enclosed building |
For existing plants, application may be difficult due to the space requirements |
c |
Use dust suppression systems such as water cannons or water sprinklers |
Not applicable for mixing operations carried out indoors. Not applicable for processes that require dry materials. The application is also limited in regions with water shortages or with very low temperatures |
d |
Use enclosed equipment for operations with dusty material (such as drying, mixing, milling, air separation and pelletisation) with an air extraction system connected to an abatement system |
Generally applicable |
e |
Use an extraction system for dusty and gaseous emissions, such as a hood in combination with a dust and gas abatement system |
Generally applicable |
|
Technique |
Applicability |
a |
Briquetting and pelletisation of raw materials |
Applicable only when the process and the furnace can use pelletised raw materials |
b |
Enclosed charging system such as single jet burner, door sealing(20), closed conveyers or feeders equipped with an air extraction system in combination with a dust and gas abatement system |
The jet burner is applicable only for flash furnaces |
c |
Operate the furnace and gas route under negative pressure and at a sufficient gas extraction rate to prevent pressurisation |
Generally applicable |
d |
Capture hood/enclosures at charging and tapping points in combination with an off-gas abatement system (e.g. housing/tunnel for ladle operation during tapping, and which is closed with a movable door/barrier equipped with a ventilation and abatement system) |
Generally applicable |
e |
Encapsulate the furnace in vented housing |
Generally applicable |
f |
Maintain furnace sealing |
Generally applicable |
g |
Hold the temperature in the furnace at the lowest required level |
Generally applicable |
h |
Boosted suction systems(20) |
Generally applicable |
i |
Enclosed building in combination with other techniques to collect the diffuse emissions |
Generally applicable |
j |
Double bell charging system for shaft/blast furnaces |
Generally applicable |
k |
Select and feed the raw materials according to the type of furnace and abatement techniques used |
Generally applicable |
l |
Use of lids on throats of rotary anode furnace |
Generally applicable |
|
Technique |
a |
Operate the furnace and gas route under negative pressure and at a sufficient gas extraction rate to prevent pressurisation |
b |
Oxygen enrichment |
c |
Primary hood over the converter opening to collect and transfer the primary emissions to an abatement system |
d |
Addition of materials (e.g. scrap and flux) through the hood |
e |
System of secondary hoods in addition to the main one to capture emissions during charging and tapping operations |
f |
Furnace located in enclosed building |
g |
Apply motor-driven secondary hoods, to move them according to the process stage, to increase the efficiency of the collection of secondary emissions |
h |
Boosted suction systems(21) and automatic control to prevent blowing when the converter is ‘rolled out’ or ‘rolled in’ |
|
Technique |
a |
Operate furnace and gas route under negative pressure during charging, skimming and tapping operations |
b |
Oxygen enrichment |
c |
Mouth with closed lids during operation |
d |
Boosted suction systems(22) |
|
Technique |
Applicability |
a |
Operate the furnace and gas route under negative pressure and at a sufficient gas extraction rate to prevent pressurisation |
Generally applicable |
b |
Oxygen enrichment |
Generally applicable |
c |
Furnace located in enclosed building in combination with techniques to collect and transfer diffuse emissions from charging and tapping to an abatement system |
Generally applicable |
d |
Primary hood over the converter opening to collect and transfer the primary emissions to an abatement system |
Generally applicable |
e |
Hoods or crane integrated hood to collect and transfer the emissions from charging and tapping operations to an abatement system |
For existing plants, a crane integrated hood is only applicable to major upgrades of the furnace hall |
f |
Addition of materials (e.g. scrap and flux) through the hood |
Generally applicable |
g |
Boosted suction system(23) |
Generally applicable |
|
Technique |
a |
Dust suppression techniques such as a water spray for handling, storage and crushing of slag |
b |
Grinding and flotation performed with water |
c |
Delivery of the slag to the final storage area via hydro transport in a closed pipeline |
d |
Maintain a water layer in the pond or use a dust suppressant such as lime milk in dry areas |
|
Technique |
a |
Dust suppression techniques such as a water spray for handling, storage and crushing of the final slag |
b |
Operation of the furnace under negative pressure |
c |
Enclosed furnace |
d |
Housing, enclosure and hood to collect and transfer the emissions to an abatement system |
e |
Covered launder |
|
Technique |
a |
Use an enclosed tundish |
b |
Use a closed intermediate ladle |
c |
Use a hood, equipped with an air extraction system, over the casting ladle and over the casting wheel |
|
Technique |
Applicability |
a |
Addition of surfactants to the electrowinning cells |
Generally applicable |
b |
Use covers or a hood to collect and transfer the emissions to an abatement system |
Only applicable for electrowinning cells or refining cells for low-purity anodes. Not applicable when the cell needs to remain uncovered to maintain the cell temperature at workable levels (approximately 65 °C) |
c |
Closed and fixed pipelines for transferring the electrolyte solutions |
Generally applicable |
d |
Gas extraction from the washing chambers of the cathode stripping machine and anode scrap washing machine |
Generally applicable |
|
Technique |
a |
Use enclosures or hoods to collect and transfer the emissions to an abatement system |
b |
Use covering for the melts in holding and casting furnaces |
c |
Boosted suction system(24) |
|
Technique |
Applicability |
a |
Encapsulate the pickling line with a solution of isopropanol operating in a closed circuit |
Only applicable for pickling of copper wire rod in continuous operations |
b |
Encapsulate the pickling line to collect and transfer the emissions to an abatement system |
Only applicable for acid pickling in continuous operations |
1.2.3.2.
Parameter |
BAT |
Process |
BAT-AEL (mg/Nm3) |
Dust |
BAT 37 |
Reception, storage, handling, transport, metering, mixing, blending, crushing, drying, cutting and screening of raw materials, and the pyrolytic treatment of copper turnings in primary and secondary copper production |
2-5(25) (28) |
BAT 38 |
Concentrate drying in primary copper production |
3-5(26) (28) (29) |
|
BAT 39 |
Primary copper smelter and converter (emissions other than those that are routed to the sulphuric acid or liquid SO2 plant or power plant) |
2-5(27) (28) |
|
BAT 40 |
Secondary copper smelter and converter and processing of secondary copper intermediates (emissions other than those that are routed to the sulphuric acid plant) |
2-4(26) (28) |
|
BAT 41 |
Secondary copper holding furnace |
≤ 5(25) |
|
BAT 42 |
Copper-rich slag furnace processing |
2-5(25) (30) |
|
BAT 43 |
Anode furnace (in primary and secondary copper production) |
2-5(26) (30) |
|
BAT 44 |
Anode casting (in primary and secondary copper production) |
≤ 5-15(26) (31) |
|
BAT 45 |
Copper melting furnace |
2-5(26) (32) |
1.2.3.3.
|
Technique(33) |
Applicability |
a |
Afterburner or post-combustion chamber or regenerative thermal oxidiser |
The applicability is restricted by the energy content of the off-gases that need to be treated, as off-gases with a lower energy content require a higher fuel use |
b |
Injection of adsorbent in combination with a bag filter |
Generally applicable |
c |
Design of furnace and the abatement techniques according to the raw materials available |
Only applicable to new furnaces or major upgrades of existing furnaces |
d |
Select and feed the raw materials according to the furnace and the abatement techniques used |
Generally applicable |
e |
Thermal destruction of TVOC at high temperatures in the furnace (> 1 000 °C) |
Generally applicable |
Parameter |
BAT-AEL (mg/Nm3)(34) (35) |
TVOC |
3-30 |
|
Technique |
a |
Process reagent (solvent) with lower steam pressure |
b |
Closed equipment such as closed mixing tanks, closed settlers and closed storage tanks |
|
Technique |
a |
Select and feed the raw materials according to the furnace and the abatement techniques used |
b |
Optimise combustion conditions to reduce the emissions of organic compounds |
c |
Use charging systems, for a semi-closed furnace, to give small additions of raw material |
d |
Thermal destruction of PCDD/F in the furnace at high temperatures (> 850 °C) |
e |
Use oxygen injection in the upper zone of the furnace |
f |
Internal burner system |
g |
Post-combustion chamber or afterburner or regenerative thermal oxidiser(36) |
h |
Avoid exhaust systems with a high dust build-up for temperatures > 250 °C |
i |
Rapid quenching(36) |
j |
Injection of adsorption agent in combination with an efficient dust collection system(36) |
Parameter |
BAT-AEL (ng I-TEQ/Nm3)(37) |
PCDD/F |
≤ 0,1 |
1.2.3.4.
|
Technique |
Applicability |
||||
a |
Dry or semi-dry scrubber |
Generally applicable |
||||
b |
Wet scrubber |
Applicability may be limited in the following cases:
|
||||
c |
Polyether-based absorption/desorption system |
Not applicable in the case of secondary copper production. Not applicable in the absence of a sulphuric acid or liquid SO2 plant |
Parameter |
Process |
BAT-AEL (mg/Nm3)(38) |
SO2 |
Primary copper production |
50-500(39) |
Secondary copper production |
50-300 |
1.2.3.5.
1.2.4.
|
Technique |
a |
Use of a sealed drainage system |
b |
Use of impermeable and acid-resistant floors |
c |
Use of double-walled tanks or placement in resistant bunds with impermeable floors |
1.2.5.
|
Technique |
a |
Use the steam condensate for heating the electrolysis cells, to wash the copper cathodes or send it back to steam boiler |
b |
Reuse the water collected from the cooling area, flotation process and hydro transportation of final slag in the slag concentration process |
c |
Recycle the pickling solutions and the rinse water |
d |
Treat the residues (crude) from the solvent extraction step in hydrometallurgical copper production to recover the organic solution content |
e |
Centrifuge the slurry from cleaning and settlers from the solvent extraction step in hydrometallurgical copper production |
f |
Reuse the electrolysis bleed after the metal removal stage in the electrowinning and/or the leaching process |
1.2.6.
|
Technique |
Applicability |
a |
Recover metals from the dust and slime coming from the dust abatement system |
Generally applicable |
b |
Reuse or sell the calcium compounds (e.g. gypsum) generated by the abatement of SO2 |
Applicability may be restricted depending on the metal content and on the availability of a market |
c |
Regenerate or recycle the spent catalysts |
Generally applicable |
d |
Recover metal from the waste water treatment slime |
Applicability may be restricted depending on the metal content and on the availability of a market/process |
e |
Use weak acid in the leaching process or for gypsum production |
Generally applicable |
f |
Recover the copper content from the rich slag in the slag furnace or slag flotation plant |
|
g |
Use the final slag from furnaces as an abrasive or (road) construction material or for another viable application |
Applicability may be restricted depending on the metal content and on the availability of a market |
h |
Use the furnace lining for recovery of metals or reuse as refractory material |
|
i |
Use the slag from the slag flotation as an abrasive or construction material or for another viable application |
|
j |
Use the skimming from the melting furnaces to recover the metal content |
Generally applicable |
k |
Use the spent electrolyte bleed to recover copper and nickel. Reuse the remaining acid to make up the new electrolyte or to produce gypsum |
|
l |
Use the spent anode as a cooling material in pyrometallurgical copper refining or remelting |
|
m |
Use anode slime to recover precious metals |
|
n |
Use the gypsum from the waste water treatment plant in the pyrometallurgical process or for sale |
Applicability may be restricted depending on the quality of the generated gypsum |
o |
Recover metals from sludge |
Generally applicable |
p |
Reuse the depleted electrolyte from the hydrometallurgical copper process as a leaching agent |
Applicability may be restricted depending on the metal content and on the availability of a market/process |
q |
Recycle copper scales from rolling in a copper smelter |
Generally applicable |
r |
Recover metals from the spent acid pickling solution and reuse the cleaned acid solution |
1.3. BAT CONCLUSIONS FOR ALUMINIUM PRODUCTION INCLUDING ALUMINA AND ANODE PRODUCTION
1.3.1.
1.3.1.1.
|
Technique |
Description |
Applicability |
a |
Plate heat exchangers |
Plate heat exchangers allow a higher heat recovery from the liquor flowing to the precipitation area in comparison with other techniques such as flash cooling plants |
Applicable if the energy from the cooling fluid can be reused in the process and if the condensate balance and the liquor conditions allow it |
b |
Circulating fluidised bed calciners |
Circulating fluidised bed calciners have a much higher energy efficiency than rotary kilns, since the heat recovery from the alumina and the flue-gas is greater |
Only applicable to smelter-grade aluminas. Not applicable to speciality/non-smelter-grade aluminas, as these require a higher level of calcination that can currently only be achieved with a rotary kiln |
c |
Single stream digestion design |
The slurry is heated up in one circuit without using live steam and therefore without dilution of the slurry (in contrast to the double-stream digestion design) |
Only applicable to new plants |
d |
Selection of the bauxite |
Bauxite with a higher moisture content carries more water into the process, which increases the energy need for evaporation. In addition, bauxites with a high monohydrate content (boehmite and/or diaspore) require a higher pressure and temperature in the digestion process, leading to higher energy consumption |
Applicable within the constraints related to the specific design of the plant, since some plants are specifically designed for a certain quality of bauxite, which limits the use of alternative bauxite sources |
1.3.1.2.
1.3.1.3.
|
Technique |
a |
Reduce the volume of bauxite residues by compacting in order to minimise the moisture content, e.g. using vacuum or high-pressure filters to form a semi-dry cake |
b |
Reduce/minimise the alkalinity remaining in the bauxite residues in order to allow disposal of the residues in a landfill |
1.3.2.
1.3.2.1.
1.3.2.1.1.
|
Technique(40) |
a |
Dry scrubber using coke as the adsorbent agent, with or without precooling, followed by a bag filter |
b |
Regenerative thermal oxidiser |
c |
Catalytic thermal oxidiser |
Parameter |
Process |
BAT-AEL (mg/Nm3) |
||||
Dust |
|
2-5(41) |
||||
BaP |
Hot pitch storage, paste mixing, cooling and forming |
0,001-0,01(42) |
1.3.2.1.2.
|
Technique(43) |
Applicability |
||||
a |
Use of raw materials and fuels containing a low amount of sulphur |
Generally applicable for reducing SO2 emissions |
||||
b |
Dry scrubber using alumina as the adsorbent agent followed by a bag filter |
Generally applicable for reducing dust, PAH and fluoride emissions |
||||
c |
Wet scrubber |
Applicability for reducing dust, SO2, PAH and fluoride emissions may be limited in the following cases:
|
||||
d |
Regenerative thermal oxidiser in combination with a dust abatement system |
Generally applicable for reducing dust and PAH emissions. |
Parameter |
BAT-AEL (mg/Nm3) |
Dust |
2-5(44) |
BaP |
0,001-0,01(45) |
HF |
0,3-0,5(44) |
Total fluorides |
≤ 0,8(45) |
Parameter |
BAT-AEL (mg/Nm3) |
Dust |
2-5(46) |
BaP |
0,001-0,01(47) |
HF |
≤ 3(46) |
1.3.2.2.
1.3.2.3.
1.3.3.
1.3.3.1.
|
Technique |
a |
Use of paste with a pitch content between 25 % and 28 % (dry paste) |
b |
Upgrade the manifold design to allow closed point feeding operations and improved off-gas collection efficiency |
c |
Alumina point feeding |
d |
Increased anode height combined with the treatment in BAT 67 |
e |
Anode top hooding when high current density anodes are used, connected to the treatment in BAT 67 |
|
Technique |
a |
Automatic multiple point feeding of alumina |
b |
Complete hood coverage of the cell and adequate off-gas extraction rates (to lead the off-gas to the treatment in BAT 67) taking into account fluoride generation from bath and carbon anode consumption |
c |
Boosted suction system connected to the abatement techniques listed in BAT 67 |
d |
Minimisation of the time for changing anodes and other activities that require cell hoods to be removed |
e |
Efficient process control system avoiding process deviations that might otherwise lead to increased cell evolution and emissions |
f |
Use of a programmed system for cell operations and maintenance |
g |
Use of established efficient cleaning methods in the rodding plant to recover fluorides and carbon |
h |
Storage of removed anodes in a compartment near the cell, connected to the treatment in BAT 67, or storage of the butts in confined boxes |
1.3.3.1.1.
Parameter |
BAT-AEL (mg/Nm3)(48) |
Dust |
≤ 5-10 |
|
Technique(49) |
Applicability |
||||
a |
Dry scrubber using alumina as the adsorbent agent followed by a bag filter |
Generally applicable |
||||
b |
Dry scrubber using alumina as the adsorbent agent followed by a bag filter and a wet scrubber |
Applicability may be limited in the following cases:
|
Parameter |
BAT-AEL (mg/Nm3) |
Dust |
2-5(50) |
HF |
≤ 1,0(50) |
Total fluorides |
≤ 1,5(51) |
1.3.3.1.2.
Parameter |
BAT |
BAT-AELs for existing plants (kg/t Al)(52) (53) |
BAT-AELs for new plants (kg/t Al)(52) |
Dust |
Combination of BAT 64, BAT 65 and BAT 67 |
≤ 1,2 |
≤ 0,6 |
Total fluorides |
≤ 0,6 |
≤ 0,35 |
|
Technique |
a |
Use of liquid metal from electrolysis and uncontaminated aluminium material, i.e. solid material free of substances such as paint, plastic or oil (e.g. the top and the bottom part of the billets that are cut for quality reasons) |
b |
Bag filter(54) |
Parameter |
BAT-AEL (mg/Nm3)(55) (56) |
Dust |
2-25 |
1.3.3.1.3.
|
Technique |
Applicability |
||||
a |
Use of low-sulphur anodes |
Generally applicable |
||||
b |
Wet scrubber(57) |
Applicability may be limited in the following cases:
|
Parameter |
BAT-AEL (kg/t Al)(58) (59) |
SO2 |
≤ 2,5-15 |
1.3.3.1.4.
|
Technique |
Applicability |
a |
Automatic multiple point feeding of alumina |
Generally applicable |
b |
Computer control of the electrolysis process based on active cell databases and monitoring of cell operating parameters |
Generally applicable |
c |
Automatic anode effect suppression |
Not applicable to Søderberg cells because the anode design (one piece only) does not allow the bath flow associated with this technique |
1.3.3.1.5.
1.3.3.2.
1.3.3.3.
1.3.4.
1.3.4.1.
|
Technique |
a |
Magnetic separation of ferrous metals |
b |
Eddy current separation (using moving electromagnetic fields) of aluminium from the other constituents |
c |
Relative density separation (using a fluid with a different density) of different metals and non-metallic constituents |
1.3.4.2.
|
Technique |
Applicability |
a |
Preheating of the furnace charge with the exhaust gas |
Only applicable for non-rotating furnaces |
b |
Recirculation of the gases with unburnt hydrocarbons back into the burner system |
Only applicable for reverberatory furnaces and dryers |
c |
Supply the liquid metal for direct moulding |
Applicability is limited by the time needed for the transportation (maximum 4-5 hours) |
1.3.4.3.
1.3.4.3.1.
|
Technique |
a |
Closed or pneumatic conveyor, with an air extraction system |
b |
Enclosures or hoods for the charging and for the discharge points, with an air extraction system |
|
Technique |
Applicability |
a |
Placing a hood on top of the furnace door and at the taphole with off-gas extraction connected to a filtration system |
Generally applicable |
b |
Fume collection enclosure that covers both the charging and tapping zones |
Only applicable for stationary drum furnaces |
c |
Sealed furnace door(61) |
Generally applicable |
d |
Sealed charging carriage |
Only applicable for non-rotating furnaces |
e |
Boosted suction system that can be modified according to the process needed(61) |
Generally applicable |
|
Technique |
a |
Cooling of skimmings/dross, as soon as they are skimmed from the furnace, in sealed containers under inert gas |
b |
Prevention of wetting of the skimmings/dross |
c |
Compaction of skimmings/dross with an air extraction and dust abatement system |
1.3.4.3.2.
Parameter |
BAT-AEL (mg/Nm3)(62) |
Dust |
≤ 5 |
Parameter |
BAT-AEL (mg/Nm3)(63) |
Dust |
2-5 |
|
Technique |
a |
Use of uncontaminated aluminium material i.e. solid material free of substances such as paint, plastic or oil (e.g. billets) |
b |
Optimise combustion conditions to reduce the emissions of dust |
c |
Bag filter |
Parameter |
BAT-AEL (mg/Nm3)(64) (65) |
Dust |
2-5 |
1.3.4.3.3.
|
Technique(66) |
a |
Select and feed the raw materials according to the furnace and the abatement techniques used |
b |
Internal burner system for melting furnaces |
c |
Afterburner |
d |
Rapid quenching |
e |
Activated carbon injection |
Parameter |
Unit |
BAT-AEL |
TVOC |
mg/Nm3 |
≤ 10-30(67) |
PCDD/F |
ng I-TEQ/Nm3 |
≤ 0,1(68) |
1.3.4.3.4.
Technique |
|
a |
Select and feed the raw materials according to the furnace and the abatement techniques used(69) |
b |
Ca(OH)2 or sodium bicarbonate injection in combination with a bag filter(69) |
c |
Control of the refining process, adapting the quantity of refining gas used to remove the contaminants present into the molten metals |
d |
Use of dilute chlorine with inert gas in the refining process |
Parameter |
BAT-AEL (mg/Nm3) |
HCl |
≤ 5-10(70) |
Cl2 |
≤ 1(71) (72) |
HF |
≤ 1(73) |
1.3.4.4.
|
Technique |
a |
Reuse collected dust in the process in the case of a melting furnace using salt cover or in the salt slag recovery process |
b |
Full recycling of the salt slag |
c |
Apply skimmings/dross treatment to recover aluminium in the case of furnaces that do not use salt cover |
|
Technique |
Applicability |
a |
Increase the quality of raw material used through the separation of the non-metallic constituents and metals other than aluminium for scraps where aluminium is mixed with other constituents |
Generally applicable |
b |
Remove oil and organic constituents from contaminated swarf before melting |
Generally applicable |
c |
Metal pumping or stirring |
Not applicable for rotary furnaces |
d |
Tilting rotary furnace |
There may be restrictions on the use of this furnace due to the size of the feed materials |
1.3.5.
1.3.5.1.
|
Technique |
a |
Enclose equipment with gas extraction connected to a filtration system |
b |
Hood with gas extraction connected to a filtration system |
1.3.5.2.
Parameter |
BAT-AEL (mg/Nm3)(74) |
Dust |
2-5 |
1.3.5.3.
|
Technique(75) |
a |
Activated carbon injection |
b |
Afterburner |
c |
Wet scrubber with H2SO4 solution |
Parameter |
BAT-AEL (mg/Nm3)(76) |
NH3 |
≤ 10 |
PH3 |
≤ 0,5 |
H2S |
≤ 2 |
1.4. BAT CONCLUSIONS FOR LEAD AND/OR TIN PRODUCTION
1.4.1.
1.4.1.1.
|
Technique |
Applicability |
a |
Enclosed conveyer or pneumatic transfer system for dusty material |
Generally applicable |
b |
Enclosed equipment. When dusty materials are used the emissions are collected and sent to an abatement system |
Only applicable for feed blends prepared with a dosing bin or loss-in-weight system |
c |
Mixing of raw materials carried out in an enclosed building |
Only applicable for dusty materials. For existing plants, application may be difficult due to the space required |
d |
Dust suppression systems such as water sprays |
Only applicable for mixing carried out outdoors |
e |
Pelletisation of raw materials |
Applicable only when the process and the furnace can use pelletised raw materials |
|
Technique |
a |
Enclosed conveyer or pneumatic transfer system for dusty material |
b |
Enclosed equipment. When dusty materials are used the emissions are collected and sent to an abatement system |
|
Technique |
Applicability |
a |
Encapsulated charging system with an air extraction system |
Generally applicable |
b |
Sealed or enclosed furnaces with door sealing(77) for processes with a discontinuous feed and output |
Generally applicable |
c |
Operate furnace and gas routes under negative pressure and at a sufficient gas extraction rate to prevent pressurisation |
Generally applicable |
d |
Capture hood/enclosures at charging and tapping points |
Generally applicable |
e |
Enclosed building |
Generally applicable |
f |
Complete hood coverage with an air extraction system |
In existing plants or major upgrades of existing plants, application may be difficult due to the space requirements |
g |
Maintain furnace sealing |
Generally applicable |
h |
Maintain the temperature in the furnace at the lowest required level |
Generally applicable |
i |
Apply a hood at the tapping point, ladles and drossing area with an air extraction system |
Generally applicable |
j |
Pretreatment of dusty raw material, such as pelletisation |
Applicable only when the process and the furnace can use pelletised raw materials |
k |
Apply a doghouse for ladles during tapping |
Generally applicable |
l |
An air extraction system for charging and tapping area connected to a filtration system |
Generally applicable |
|
Technique |
a |
Hood on the crucible furnace or kettle with an air extraction system |
b |
Lids to close the kettle during the refining reactions and addition of chemicals |
c |
Hood with air extraction system at launders and tapping points |
d |
Temperature control of the melt |
e |
Closed mechanical skimmers for removal of dusty dross/residues |
1.4.1.2.
Parameter |
BAT-AEL (mg/Nm3)(78) |
Dust |
≤ 5 |
Parameter |
BAT-AEL (mg/Nm3)(79) |
Dust |
≤ 5 |
Parameter |
BAT-AEL (mg/Nm3) |
Dust |
2-4(80) (81) |
Pb |
≤ 1(82) |
|
Technique |
a |
For pyrometallurgical processes: maintain the temperature of the melt bath at the lowest possible level according to the process stage in combination with a bag filter |
b |
For hydrometallurgical processes: use a wet scrubber |
Parameter |
BAT-AEL (mg/Nm3) |
Dust |
2-4(83) (84) |
Pb |
≤ 1(85) |
1.4.1.3.
|
Technique(86) |
Applicability |
a |
Select and feed the raw materials according to the furnace and the abatement techniques used |
Generally applicable |
b |
Optimise combustion conditions to reduce the emissions of organic compounds |
Generally applicable |
c |
Afterburner or regenerative thermal oxidiser |
The applicability is restricted by the energy content of the off-gases that need to be treated, as off-gases with a lower energy content lead to a higher use of fuels |
Parameter |
BAT-AEL (mg/Nm3)(87) |
TVOC |
10-40 |
Technique |
|
a |
Select and feed the raw materials according to the furnace and the abatement techniques used(88) |
b |
Use charging systems, for a semi-closed furnace, to give small additions of raw material(88) |
c |
Internal burner system(88) for melting furnaces |
d |
Afterburner or regenerative thermal oxidiser(88) |
e |
Avoid exhaust systems with a high dust build-up at temperatures > 250 °C(88) |
f |
Rapid quenching(88) |
g |
Injection of adsorption agent in combination with efficient dust collection system(88) |
h |
Use of efficient dust collection system |
i |
Use of oxygen injection in the upper zone of the furnace |
j |
Optimise combustion conditions to reduce the emissions of organic compounds(88) |
Parameter |
BAT-AEL (ng I-TEQ/Nm3)(89) |
PCDD/F |
≤ 0,1 |
1.4.1.4.
|
Technique |
Applicability |
||||
a |
Alkaline leaching of raw materials that contain sulphur in the form of sulphate |
Generally applicable |
||||
b |
Dry or semi-dry scrubber(90) |
Generally applicable |
||||
c |
Wet scrubber(90) |
Applicability may be limited in the following cases:
|
||||
d |
Fixation of sulphur in the smelt phase |
Only applicable for secondary lead production |
Parameter |
BAT-AEL (mg/Nm3)(91) (92) |
SO2 |
50-350 |
1.4.2.
1.4.3.
1.4.4.
|
Technique |
Applicability |
a |
Reuse of the dust from the dust removal system in the lead production process |
Generally applicable |
b |
Se and Te recovery from wet or dry gas cleaning dust/sludge |
The applicability can be limited by the quantity of mercury present |
c |
Ag, Au, Bi, Sb and Cu recovery from the refining dross |
Generally applicable |
d |
Recovery of metals from the waste water treatment sludge |
Direct smelting of the waste water treatment plant sludge might be limited by the presence of elements such as As, Tl and Cd |
e |
Addition of flux materials that make the slag more suitable for external use |
Generally applicable |
|
Technique |
Applicability |
a |
Reuse as a pickling agent |
Generally applicable depending on the local conditions such as presence of the pickling process and compatibility of the impurities present in the acid with the process |
b |
Reuse as raw material in a chemical plant |
Applicability may be restricted depending on the local availability of a chemical plant |
c |
Regeneration of the acid by cracking |
Only applicable when a sulphuric acid or liquid sulphur dioxide plant is present |
d |
Production of gypsum |
Only applicable if the impurities present in the recovery acid do not affect the gypsum quality or if gypsum of a lower quality can be used for other purposes such as a flux agent |
e |
Production of sodium sulphate |
Only applicable for the alkaline leaching process |
|
Technique |
a |
Reuse the residues in the smelting process to recover lead and other metals |
b |
Treat the residues and the wastes in dedicated plants for material recovery |
c |
Treat the residues and the wastes so that they can be used for other applications |
1.5. BAT CONCLUSIONS FOR ZINC AND/OR CADMIUM PRODUCTION
1.5.1.
1.5.1.1.
1.5.1.1.1.
|
Technique |
Applicability |
a |
Use a waste heat boiler and turbines to produce electricity |
Applicability may be restricted depending on energy prices and the energy policy of the Member State |
b |
Use a waste heat boiler and turbines to produce mechanical energy to be used within the process |
Generally applicable |
c |
Use a waste heat boiler to produce heat to be used within the process and/or for office heating |
Generally applicable |
1.5.1.1.2.
1.5.1.1.2.1. Diffuse emissions
|
Technique |
a |
Wet feeding |
b |
Completely enclosed process equipment connected to an abatement system |
|
Technique |
a |
Perform operations under negative pressure |
b |
Completely enclosed process equipment connected to an abatement system |
|
Technique |
Applicability |
a |
Cover tanks with a lid |
Generally applicable |
b |
Cover process liquid inlet and outlet launders |
Generally applicable |
c |
Connect tanks to a central mechanical draught abatement system or to a single tank abatement system |
Generally applicable |
d |
Cover vacuum filters with hoods and connect them to an abatement system |
Only applicable to the filtering of hot liquids in the leaching and solid-liquid separation stages |
1.5.1.1.2.2. Channelled emissions
Parameter |
BAT-AEL (mg/Nm3)(93) |
Dust |
≤ 5 |
|
Technique(94) |
a |
Wet scrubber |
b |
Demister |
c |
Centrifugal system |
Parameter |
BAT-AEL (mg/Nm3)(95) |
Zn |
≤ 1 |
H2SO4 |
< 10 |
Sum of AsH3 and SbH3 |
≤ 0,5 |
1.5.1.1.3.
1.5.1.1.4.
|
Technique |
a |
Return of the bleed from the boiler and the water from the closed cooling circuits of the roaster to the wet gas cleaning or the leaching stage |
b |
Return of the waste water from the cleaning operations/spills of the roaster, the electrolysis and the casting to the leaching stage |
c |
Return of the waste water from the cleaning operations/spills of the leaching and purification, the filter cake washing and the wet gas scrubbing to the leaching and/or purification stages |
1.5.1.1.5.
|
Technique |
Applicability |
a |
Reuse of the dust collected in the concentrate storage and handling within the process (together with the concentrate feed) |
Generally applicable |
b |
Reuse of the dust collected in the roasting process via the calcine silo |
Generally applicable |
c |
Recycling of residues containing lead and silver as raw material in an external plant |
Applicable depending on the metal content and on the availability of a market/process |
d |
Recycling of residues containing Cu, Co, Ni, Cd, Mn as raw material in an external plant to obtain a saleable product |
Applicable depending on the metal content and on the availability of a market/process |
|
Technique |
Applicability |
a |
Pyrometallurgical treatment in a Waelz kiln |
Only applicable to neutral leaching wastes that do not contain too many zinc ferrites and/or do not contain high concentrations of precious metals |
b |
Jarofix process |
Only applicable to jarosite iron residues. Limited applicability due to an existing patent |
c |
Sulphidation process |
Only applicable to jarosite iron residues and direct leach residues |
d |
Compacting iron residues |
Only applicable to goethite residues and gypsum-rich sludge from the waste water treatment plant |
1.5.1.2.
1.5.1.2.1.
1.5.1.2.1.1. Channelled dust emissions
Parameter |
BAT-AEL (mg/Nm3)(96) (97) |
Dust |
2-5 |
Parameter |
BAT-AEL (mg/Nm3)(98) |
SO2 |
≤ 500 |
1.5.2.
1.5.2.1.
1.5.2.1.1.
Parameter |
BAT-AEL (mg/Nm3)(99) |
Dust |
≤ 5 |
Parameter |
BAT-AEL (mg/Nm3)(100) (101) (102) |
Dust |
2-5 |
1.5.2.1.2.
|
Technique(103) |
Applicability |
a |
Injection of adsorbent (activated carbon or lignite coke) followed by a bag filter and/or ESP |
Generally applicable |
b |
Thermal oxidiser |
Generally applicable |
c |
Regenerative thermal oxidiser |
May not be applicable due to safety reasons |
Parameter |
Unit |
BAT-AEL |
TVOC |
mg/Nm3 |
2-20(104) |
PCDD/F |
ng I-TEQ/Nm3 |
≤ 0,1(105) |
1.5.2.1.3.
|
Technique(106) |
Process |
||||
a |
Injection of adsorbent followed by a bag filter |
|
||||
b |
Wet scrubber |
|
Parameter |
BAT-AEL (mg/Nm3)(107) |
HCl |
≤ 1,5 |
HF |
≤ 0,3 |
1.5.2.2.
1.5.3.
1.5.3.1.
1.5.3.1.1.
1.5.3.1.2.
Parameter |
BAT-AEL (mg/Nm3)(108) |
Dust |
≤ 5 |
1.5.3.2.
1.5.3.3.
|
Technique |
a |
Use of the oxidised fraction of the zinc dross and the zinc-bearing dust from the melting furnaces in the roasting furnace or in the hydrometallurgical zinc production process |
b |
Use of the metallic fraction of the zinc dross and the metallic dross from cathode casting in the melting furnace or recovery as zinc dust or zinc oxide in a zinc refining plant |
1.5.4.
1.5.4.1.
1.5.4.1.1.
|
Technique |
a |
Central extraction system connected to an abatement system for leaching and solid-liquid separation in hydrometallurgical production; for briquetting/pelletising and fuming in pyrometallurgical production; and for melting, alloying and casting processes |
b |
Cover cells for the electrolysis stage in hydrometallurgical production |
1.5.4.1.2.
|
Technique(109) |
Applicability |
||||
a |
Bag filter |
Generally applicable |
||||
b |
ESP |
Generally applicable |
||||
c |
Wet scrubber |
Applicability may be limited in the following cases:
|
Parameter |
BAT-AEL (mg/Nm3)(110) |
Dust |
2-3 |
Cd |
≤ 0,1 |
1.5.4.2.
|
Technique |
Applicability |
a |
Extract the cadmium from the zinc process as a cadmium-rich cementate in the purification section, further concentrate and refine it (by electrolysis or a pyrometallurgical process) and finally transform it into marketable cadmium metal or cadmium compounds |
Only applicable if an economically viable demand exists |
b |
Extract the cadmium from the zinc process as a cadmium-rich cementate in the purification section, and then apply a set of hydrometallurgical operations in order to obtain a cadmium-rich precipitate (e.g. cement (Cd metal), Cd(OH)2) that is landfilled, while all other process flows are recycled in the cadmium plant or in the zinc plant flow |
Only applicable if suitable landfill is available |
1.6. BAT CONCLUSIONS FOR PRECIOUS METALS PRODUCTION
1.6.1.
1.6.1.1.
|
Technique |
a |
Enclose pretreatment areas and transfer systems for dusty materials |
b |
Connect pretreatment and handling operations to dust collectors or extractors via hoods and a ductwork system for dusty materials |
c |
Electrically interlock pretreatment and handling equipment with their dust collector or extractor, in order to ensure that no equipment may be operated unless the dust collector and filtering system are in operation |
|
Technique |
a |
Enclose buildings and/or smelting furnace areas |
b |
Perform operations under negative pressure |
c |
Connect furnace operations to dust collectors or extractors via hoods and a ductwork system |
d |
Electrically interlock furnace equipment with their dust collector or extractor, in order to ensure that no equipment may be operated unless the dust collector and filtering system are in operation |
|
Technique |
a |
Closed tanks/vessels and closed pipes for transfer of solutions |
b |
Hoods and extraction systems for electrolytic cells |
c |
Water curtain for gold production, to prevent chlorine gas emissions during the leaching of anode slimes with hydrochloric acid or other solvents |
|
Technique |
a |
Containment measures, such as sealed or enclosed reaction vessels, storage tanks, solvent extraction equipment and filters, vessels and tanks fitted with level control, closed pipes, sealed drainage systems, and planned maintenance programmes |
b |
Reaction vessels and tanks connected to a common ductwork system with off-gas extraction (automatic standby/back-up unit available in case of failure) |
|
Technique |
a |
Connect all calcining furnaces, incinerators and drying ovens to a ductwork system extracting process exhaust gases |
b |
Scrubber plant on a priority electricity circuit which is served by a back-up generator in the event of power failure |
c |
Operating start-up and shutdown, spent acid disposal, and fresh acid make-up of scrubbers via an automated control system |
|
Technique |
a |
Enclosed furnace with negative pressure |
b |
Appropriate housing, enclosures and capture hoods with efficient extraction/ventilation |
1.6.1.2.
|
Technique(111) |
Applicability |
a |
Bag filter |
May not be applicable for off-gases containing a high level of volatilised selenium |
b |
Wet scrubber in combination with an ESP, allowing the recovery of selenium |
Only applicable to off-gases containing volatilised selenium (e.g. Doré metal production) |
Parameter |
BAT-AEL (mg/Nm3)(112) |
Dust |
2-5 |
1.6.1.3.
|
Technique(113) |
a |
Alkaline scrubber with caustic soda |
b |
Scrubber with oxidation agents (e.g. oxygen, hydrogen peroxide) and reducing agents (e.g. nitric acid, urea) for those vessels in hydrometallurgical operations with the potential to generate high concentrations of NOX. It is often applied in combination with BAT 141(a) |
Parameter |
BAT-AEL (mg/Nm3)(114) |
NOX |
70-150 |
1.6.1.4.
|
Technique(115) |
Applicability |
||||
a |
Lime injection in combination with a bag filter |
Generally applicable |
||||
b |
Wet scrubber |
Applicability may be limited in the following cases:
|
Parameter |
BAT-AEL (mg/Nm3)(116) |
SO2 |
50-480 |
Parameter |
BAT-AEL (mg/Nm3)(117) |
SO2 |
50-100 |
1.6.1.5.
Parameter |
BAT-AEL (mg/Nm3)(118) |
HCl |
≤ 5-10 |
Cl2 |
0,5-2 |
1.6.1.6.
Parameter |
BAT-AEL (mg/Nm3)(119) |
NH3 |
1-3 |
1.6.1.7.
|
Technique |
a |
Afterburner or regenerative thermal oxidiser(120) |
b |
Injection of adsorption agent in combination with an efficient dust collection system(120) |
c |
Optimise combustion or process conditions for the abatement of emissions of organic compounds(120) |
d |
Avoid exhaust systems with a high dust build-up for temperatures > 250 °C(120) |
e |
Rapid quenching(120) |
f |
Thermal destruction of PCDD/F in the furnace at high temperatures (> 850 °C) |
g |
Use of oxygen injection in the upper zone of the furnace |
h |
Internal burner system(120) |
Parameter |
BAT-AEL (ng I-TEQ/Nm3)(121) |
PCDD/F |
≤ 0,1 |
1.6.2.
|
Technique |
a |
Use of sealed drainage systems |
b |
Use of double-walled tanks or placement in resistant bunds |
c |
Use of impermeable and acid-resistant floors |
d |
Automatic level control of reaction vessels |
1.6.3.
|
Technique |
a |
Recycling of spent/recovered scrubbing liquids and other hydrometallurgical reagents in leaching and other refining operations |
b |
Recycling of solutions from leaching, extraction and precipitation operations |
1.6.4.
|
Technique |
Process |
a |
Recovery of the metal content from slags, filter dust and residues of the wet dedusting system |
Doré production |
b |
Recovery of the selenium collected in the wet dedusting system’s off-gases containing volatilised selenium |
|
c |
Recovery of silver from spent electrolyte and spent slime washing solutions |
Silver electrolytic refining |
d |
Recovery of metals from residues from electrolyte purification (e.g. silver cement, copper carbonate-based residue) |
|
e |
Recovery of gold from electrolyte, slimes and solutions from the gold leaching processes |
Gold electrolytic refining |
f |
Recovery of metals from spent anodes |
Silver or gold electrolytic refining |
g |
Recovery of platinum group metals from platinum group metal-enriched solutions |
|
h |
Recovery of metals from the treatment of process end liquors |
All processes |
1.7. BAT CONCLUSIONS FOR FERRO-ALLOYS PRODUCTION
1.7.1.
|
Technique |
Applicability |
a |
Use of a steam boiler and turbines to recover the energy content of the exhaust gas and produce electricity |
Applicability may be restricted depending on energy prices and the energy policy of the Member State |
b |
Direct use of the exhaust gas as fuel within the process (e.g. for drying raw materials, preheating charging materials, sintering, heating of ladles) |
Only applicable if a demand for process heat exists |
c |
Use of the exhaust gas as fuel in neighbouring plants |
Only applicable if an economically viable demand for this type of fuel exists |
|
Technique |
Applicability |
a |
Use of a waste heat boiler and turbines to recover the energy content of the exhaust gas and produce electricity |
Applicability may be restricted depending on energy prices and the energy policy of the Member State |
b |
Use of a waste heat boiler to produce hot water |
Only applicable if an economically viable demand exists |
1.7.2.
1.7.2.1.
|
Technique |
Applicability |
a |
Use of a hooding system |
For existing plants, applicable depending on the configuration of the plant |
b |
Avoid casting by using ferro-alloys in the liquid state |
Only applicable when the consumer (e.g. steel producer) is integrated with the ferro-alloy producer |
1.7.2.2.
|
Technique(122) |
Applicability |
a |
Wet scrubber in combination with an ESP |
Generally applicable |
b |
Bag filter |
Generally applicable unless safety concerns exist related to the CO and H2 content in the exhaust gases |
Parameter |
Process |
BAT-AEL (mg/Nm3) |
||||||
Dust |
|
2-5(123) |
||||||
Crushing, briquetting, pelletising and sintering |
2-5(124) (125) |
|||||||
Open or semi-closed submerged arc furnace |
2-5(124) (126) (127) |
|||||||
|
2-5(124) |
1.7.2.3.
Parameter |
BAT-AEL (ng I-TEQ/Nm3) |
PCDD/F |
≤ 0,05(128) |
1.7.2.4.
1.7.3.
|
Technique |
Applicability |
a |
Use of slag in construction applications |
Only applicable to slags from high-carbon FeCr and SiMn production, slags from alloy recovery from steel mill residues and standard exhaust slag from FeMn and FeMo production |
b |
Use of slag as sandblasting grit |
Only applicable to slags from high-carbon FeCr production |
c |
Use of slag for refractory castables |
Only applicable to slags from high-carbon FeCr production |
d |
Use of slag in the smelting process |
Only applicable to slags from silico-calcium production |
e |
Use of slag as raw material for the production of silico-manganese or other metallurgical applications |
Only applicable to rich slag (high content of MnO) from FeMn production |
|
Technique |
Applicability(129) |
a |
Use of filter dust in the smelting process |
Only applicable to filter dust from FeCr and FeMo production |
b |
Use of filter dust in stainless steel production |
Only applicable to filter dust from crushing and screening operations in high-carbon FeCr production |
c |
Use of filter dust and sludge as a concentrate feed |
Only applicable to filter dust and sludge from the off-gas cleaning in Mo roasting |
d |
Use of filter dust in other industries |
Only applicable to FeMn, SiMn, FeNi, FeMo and FeV production |
e |
Use of micro-silica as an additive in the cement industry |
Only applicable to micro-silica from FeSi and Si production |
f |
Use of filter dust and sludge in the zinc industry |
Only applicable to furnace dust and wet scrubber sludge from the alloy recovery from steel mill residues |
1.8. BAT CONCLUSIONS FOR NICKEL AND/OR COBALT PRODUCTION
1.8.1.
|
Technique |
a |
Use of oxygen-enriched air in smelting furnaces and oxygen converters |
b |
Use of heat recovery boilers |
c |
Use of the flue-gas generated in the furnace within the process (e.g. drying) |
d |
Use of heat exchangers |
1.8.2.
1.8.2.1.
|
Technique |
a |
Sealed or closed reactors, settlers and pressure autoclaves/vessels |
b |
Use of oxygen or chlorine instead of air in leaching stages |
|
Technique |
a |
Use of a low or a high shear mixer for the solvent/aqueous mixture |
b |
Use of covers for the mixer and separator |
c |
Use of completely sealed tanks connected to an abatement system |
|
Technique |
Applicability |
a |
Collection and reuse of chlorine gas |
Only applicable to chloride-based electrowinning |
b |
Use of polystyrene beads to cover cells |
Generally applicable |
c |
Use of foaming agents to cover the cells with a stable layer of foam |
Only applicable to sulphate-based electrowinning |
1.8.2.2.
Parameter |
BAT-AEL (mg/Nm3)(130) |
Dust |
2-5 |
1.8.2.3.
Parameter |
BAT-AEL (mg/Nm3)(131) |
Ni |
≤ 1 |
Cl2 |
≤ 1 |
Parameter |
BAT-AEL (mg/Nm3)(132) |
Ni |
≤ 1 |
1.8.2.4.
|
Technique(133) |
a |
Lime injection followed by a bag filter |
b |
Wet scrubber |
1.8.2.5.
1.8.3.
|
Technique |
Applicability |
a |
Use of the granulated slag generated in the electric arc furnace (used in smelting) as an abrasive or construction material |
Applicability depends on the metal content of the slag |
b |
Use of the off-gas dust recovered from the electric arc furnace (used in smelting) as a raw material for zinc production |
Generally applicable |
c |
Use of the matte granulation off-gas dust recovered from the electric arc furnace (used in smelting) as a raw material for the nickel refinery/re-smelting |
Generally applicable |
d |
Use of the sulphur residue obtained after matte filtration in the chlorine-based leaching as a raw material for sulphuric acid production |
Generally applicable |
e |
Use of the iron residue obtained after sulphate-based leaching as a feed to the nickel smelter |
Applicability depends on the metal content of the waste |
f |
Use of the zinc carbonate residue obtained from the solvent extraction refining as a raw material for zinc production |
Applicability depends on the metal content of the waste |
g |
Use of the copper residues obtained after leaching from the sulphate- and chlorine-based leaching as a raw material for copper production |
Generally applicable |
1.9. BAT CONCLUSIONS FOR CARBON AND/OR GRAPHITE PRODUCTION
1.9.1.
1.9.1.1.
|
Technique |
a |
Back-venting of the liquid pitch storage tank |
b |
Condensation by external and/or internal cooling with air and/or water systems (e.g. conditioning towers), followed by filtration techniques (adsorption scrubbers or ESP) |
c |
Collection and transfer of collected off-gases to abatement techniques (dry scrubber or thermal oxidiser/regenerative thermal oxidiser) available at other stages of the process (e.g. mixing and shaping or baking) |
1.9.1.2.
Parameter |
BAT-AEL (mg/Nm3)(134) |
Dust |
2-5 |
BaP |
≤ 0,01(135) |
|
Technique(136) |
a |
Dry scrubber using coke as the adsorbent agent and with or without precooling, followed by a bag filter |
b |
Coke filter |
c |
Regenerative thermal oxidiser |
d |
Thermal oxidiser |
Parameter |
BAT-AEL (mg/Nm3)(137) |
Dust |
2-10(138) |
BaP |
0,001-0,01 |
|
Technique(139) |
Applicability |
a |
ESP, in combination with a thermal oxidation step (e.g. regenerative thermal oxidiser) when highly volatile compounds are expected |
Generally applicable |
b |
Regenerative thermal oxidiser, in combination with a pretreatment (e.g. ESP) in cases of a high dust content in the exhaust gas |
Generally applicable |
c |
Thermal oxidiser |
Not applicable to continuous ring furnaces |
Parameter |
BAT-AEL (mg/Nm3)(140) |
Dust |
2-10(141) |
BaP |
0,005-0,015(142) (143) |
|
Technique(144) |
a |
Dry scrubber followed by a bag filter |
b |
Coke filter |
c |
Thermal oxidiser |
Parameter |
BAT-AEL (mg/Nm3)(145) |
Dust |
2-10 |
BaP |
0,001-0,01 |
1.9.1.3.
1.9.1.4.
|
Technique(146) |
a |
Regenerative thermal oxidiser in combination with an ESP for the mixing, baking and impregnation stages |
b |
Biofilter and/or bioscrubber for the impregnation stage where special impregnation agents such as resins and biodegradable solvents are used |
Parameter |
BAT-AEL (mg/Nm3)(147) (148) |
TVOC |
≤ 10-40 |
1.9.2.
1.10. DESCRIPTION OF TECHNIQUES
1.10.1.
1.10.1.1.
Technique |
Description |
Bag filter |
Bag filters, often referred to as fabric filters, are constructed from porous woven or felted fabric through which gases flow to remove particles. The use of a bag filter requires a fabric material selection suited to the characteristics of the off-gases and the maximum operating temperature. |
Electrostatic precipitator (ESP) |
Electrostatic precipitators operate such that particles are charged and separated under the influence of an electrical field. They are capable of operating over a wide range of conditions. In a dry ESP, the collected material is mechanically removed (e.g. by shaking, vibration, compressed air), while in a wet ESP it is flushed with a suitable liquid, usually water. |
Wet scrubber |
Wet scrubbing entails separating the dust by intensively mixing the incoming gas with water, usually combined with the removal of the coarse particles through the use of centrifugal force. The removed dust is collected at the bottom of the scrubber. Also, substances such as SO2, NH3, some VOC and heavy metals may be removed |
1.10.1.2.
Technique |
Description |
Low-NOX burner |
Low-NOX burners reduce the formation of NOX by reducing peak flame temperatures, delaying but completing the combustion and increasing the heat transfer (increased emissivity of the flame). The ultra-low-NOx burners includes combustion staging (air/fuel) and flue-gas recirculation |
Oxy-fuel burner |
The technique involves the replacement of the combustion air with oxygen, with the consequent elimination/reduction of thermal NOX formation from nitrogen entering the furnace. The residual nitrogen content in the furnace depends on the purity of the oxygen supplied, on the quality of the fuel and on the potential air inlet |
Flue-gas recirculation |
This implies the reinjection of flue-gas from the furnace into the flame to reduce the oxygen content and therefore the temperature of the flame. The use of special burners is based on internal recirculation of combustion gases which cool the root of the flames and reduce the oxygen content in the hottest part of the flames |
1.10.1.3.
Technique |
Description |
Dry or semi-dry scrubber |
Dry powder or a suspension/solution of an alkaline reagent (e.g. lime or sodium bicarbonate) is introduced and dispersed in the off-gas stream. The material reacts with the acidic gaseous species (e.g. SO2) to form a solid which is removed by filtration (bag filter or electrostatic precipitator). The use of a reaction tower improves the removal efficiency of the scrubbing system. Adsorption can also be achieved by the use of packed towers (e.g. coke filter). For existing plants, the performance is linked to process parameters such as temperature (min. 60 °C), moisture content, contact time, gas fluctuations and to the capability of the dust filtration system (e.g. bag filter) to cope with the additional dust load |
Wet scrubber |
In the wet scrubbing process, gaseous compounds are dissolved in a scrubbing solution (e.g. an alkaline solution containing lime, NaOH, or H2O2). Downstream of the wet scrubber, the off-gases are saturated with water and a separation of the droplets is carried out before discharging the off-gases. The resulting liquid is further treated by a waste water process and the insoluble matter is collected by sedimentation or filtration. For existing plants, this technique may require significant space availability |
Use of low-sulphur fuels |
The use of natural gas or low-sulphur fuel oil reduces the amount of SO2 and SO3 emissions from the oxidation of sulphur contained in the fuel during combustion |
Polyether-based absorption/desorption system |
A polyether-based solvent is used to selectively absorb the SO2 from the exhaust gases. Then the absorbed SO2 is stripped in another column and the solvent is fully regenerated. The stripped SO2 is used to produce liquid SO2 or sulphuric acid |
1.10.1.4.
Technique |
Description |
Activated carbon adsorption |
This process is based on the adsorption of mercury onto the activated carbon. When the surface has adsorbed as much as it can, the adsorbed content is desorbed as part of the regeneration of the adsorbent |
Selenium adsorption |
This process is based on the use of selenium-coated spheres in a packed bed. The red amorphous selenium reacts with the mercury in the gas to form HgSe. The filter is then treated to regenerate the selenium. |
1.10.1.5.
Technique |
Description |
Afterburner or thermal oxidiser |
Combustion system in which the pollutant within the exhaust gas stream reacts with oxygen in a temperature-controlled environment to create an oxidation reaction |
Regenerative thermal oxidiser |
Combustion system that employs a regenerative process to utilise the thermal energy in the gas and carbon compounds by using refractory support beds. A manifold system is needed to change the direction of the gas flow to clean the bed. It is also known as a regenerative afterburner |
Catalytic thermal oxidiser |
Combustion system where the decomposition is carried out on a metal catalyst surface at lower temperatures, typically from 350 °C to 400 °C. It is also known as a catalytic afterburner |
Biofilter |
It consists of a bed of organic or inert material, where pollutants from off-gas streams are biologically oxidised by microorganisms |
Bioscrubber |
It combines wet gas scrubbing (absorption) and biodegradation, the scrubbing water containing a population of microorganisms suitable to oxidise the noxious gas components |
Select and feed the raw materials according to the furnace and the abatement techniques used |
The raw materials are selected in such a way that the furnace and the abatement system used to achieve the required abatement performance can treat the contaminants contained in the feed properly |
Optimise combustion conditions to reduce the emissions of organic compounds |
Good mixing of air or oxygen and carbon content, control of the temperature of the gases and residence time at high temperatures to oxidise the organic carbon comprising PCDD/F. It can also include the use of enriched air or pure oxygen |
Use charging systems, for a semi-closed furnace, to give small additions of raw material |
Add raw material in small portions in semi-closed furnaces to reduce the furnace cooling effect during charging. This maintains a higher gas temperature and prevents the reformation of PCDD/F |
Internal burner system |
The exhaust gas is directed through the burner flame and the organic carbon is converted with oxygen to CO2 |
Avoid exhaust systems with a high dust build-up for temperatures > 250 °C |
The presence of dust at temperatures above 250 °C promotes the formation of PCDD/F by de novo synthesis |
Injection of adsorption agent in combination with efficient dust collection system |
PCDD/F may be adsorbed onto dust and hence emissions can be reduced using an efficient dust filtration system. The use of a specific adsorption agent promotes this process and reduces the emissions of PCDD/F |
Rapid quenching |
PCDD/F de novo synthesis is prevented by rapid gas cooling from 400 °C to 200 °C |
1.10.2.
Techniques |
Descriptions |
Chemical precipitation |
The conversion of dissolved pollutants into an insoluble compound by adding chemical precipitants. The solid precipitates formed are subsequently separated by sedimentation, flotation or filtration. If necessary, this may be followed by ultrafiltration or reverse osmosis. Typical chemicals used for metal precipitation are lime, sodium hydroxide, and sodium sulphide. |
Sedimentation |
The separation of suspended particles and suspended material by gravitational settling |
Flotation |
The separation of solid or liquid particles from waste water by attaching them to fine gas bubbles, usually air. The buoyant particles accumulate at the water surface and are collected with skimmers |
Filtration |
The separation of solids from waste water by passing them through a porous medium. Sand is the most commonly used filtering medium |
Ultrafiltration |
A filtration process in which membranes with pore sizes of approximately 10 μm are used as the filtering medium |
Activated carbon filtration |
A filtration process in which activated carbon is used as the filtering medium |
Reverse osmosis |
A membrane process in which a pressure difference applied between the compartments separated by the membrane causes water to flow from the more concentrated solution to the less concentrated one |
1.10.3.
Techniques |
Descriptions |
Demister |
Demisters are filter devices that remove entrained liquid droplets from a gas stream. They consist of a woven structure of metal or plastic wires, with a high specific surface area. Through their momentum, small droplets present in the gas stream impinge against the wires and coalesce into bigger drops |
Centrifugal system |
Centrifugal systems use inertia to remove droplets from off-gas streams by imparting centrifugal forces |
Boosted suction system |
Systems designed to modify the extraction fan capacity based on the sources of the fumes which change over the charging, melting and tapping cycles. Automated control of the burner rate during charging is also applied to ensure a minimum gas flow during operations with the door opened |
Centrifugation of swarf |
Centrifugation is a mechanical method to separate the oil from the swarf. To increase the velocity of the sedimentation process, a centrifugation force is applied to the swarf and the oil is separated |
Drying of swarf |
The swarf drying process uses an indirectly heated rotary drum. To remove the oil, a pyrolytic process takes place at a temperature between 300 °C and 400 °C |
Sealed furnace door or furnace door sealing |
The furnace door is designed to provide efficient sealing to prevent diffuse emissions escaping and to maintain the positive pressure inside the furnace during the smelting/melting stage |