Commission Implementing Decision (EU) 2023/2749 of 11 December 2023 establishing the best available techniques (BAT) conclusions, under Directive 2010/75/EU of the European Parliament and of the Council on industrial emissions, for slaughterhouses, animal by-products and/or edible co-products industries (notified under document C(2023) 8434) (Text with EEA relevance)Text with EEA relevance

Adsorbable organically bound halogens (AOX)^{(2) (3)}

All activities

EN ISO 9562

Once every 3 months⁽⁴⁾

BAT 14

Biochemical oxygen demand (BODn)⁽⁵⁾

Various EN standards available (e.g. EN 1899-1, EN ISO 5815-1)

Once every month

Chemical oxygen demand (COD)^{(5) (6)}

No EN standard available

Once every week⁽⁷⁾

Total nitrogen (TN)⁽⁵⁾

Various EN standards available (e.g. EN 12260, EN ISO 11905-1)

Total organic carbon (TOC)^{(5) (6)}

EN 1484

Total phosphorus (TP)⁽⁵⁾

Various EN standards available (e.g. EN ISO 6878, EN ISO 15681-1 and -2, EN ISO 11885)

Total suspended solids (TSS)⁽⁵⁾

EN 872

Metals

Copper (Cu)^{(2) (3)}

Slaughterhouses

Various EN standards available (e.g. EN ISO 11885, EN ISO 17294-2 or EN ISO 15586)

Once every 6 months

Zinc (Zn)^{(2) (3)}

Chloride (Cl^-)^{(2) (3)}

• Slaughterhouses

• Hide/skin salting

• Gelatine manufacturing using bones as raw material

Various EN standards available (e.g. EN ISO 10304-1, EN ISO 15682)

Once every month⁽⁴⁾

-

CO

Combustion (e.g. in thermal oxidisers or steam boilers) of malodorous gases, including non-condensable gases

EN 15058

Once every year

BAT 15

Incineration of carcasses

-

Dust

Combustion (e.g. in thermal oxidisers or steam boilers) of malodorous gases, including non-condensable gases

EN 13284-1

BAT 15

Incineration of carcasses

-

NOX

Combustion (e.g. in thermal oxidisers or steam boilers) of malodorous gases, including non-condensable gases

EN 14792

BAT 15

Incineration of carcasses

-

SOX

Combustion (e.g. in thermal oxidisers or steam boilers) of malodorous gases, including non-condensable gases

EN 14791

BAT 15

Incineration of carcasses

-

H2S

Rendering, fat melting, blood and/or feather processing⁽²⁾

No EN standard available

BAT 25

NH3

Rendering, fat melting, blood and/or feather processing

EN ISO 21877

Combustion (e.g. in thermal oxidisers or steam boilers) of malodorous gases, including non-condensable gases

Incineration of carcasses

-

TVOC

Rendering, fat melting, blood and/or feather processing

EN 12619

BAT 25

Combustion (e.g. in thermal oxidisers or steam boilers) of malodorous gases, including non-condensable gases

Incineration of carcasses

-

Odour concentration

Slaughterhouses^{(3) (4)}

EN 13725

-

Incineration of carcasses⁽³⁾

-

Gelatine manufacturing⁽³⁾

-

Fishmeal and fish oil production⁽³⁾

BAT 25

Rendering, fat melting, blood and/or feather processing⁽³⁾

HCl

Incineration of carcasses

EN 1911

-

HF

No EN standard available

Hg

EN 13211

Metals and metalloids except mercury (As, Cd, Co, Cr, Cu, Mn, Ni, Pb, Sb, Tl, V)

EN 14385

PCDD/F

EN 1948-1, EN 1948-2, EN 1948-3

a

Energy efficiency plan and audits

An energy efficiency plan is part of the environmental management system (see BAT 1) and entails defining and calculating the specific energy consumption of the activity (or activities), setting key performance indicators on an annual basis (for example for the specific energy consumption) and planning periodic improvement targets and related actions.

Audits are carried out at least once every year to ensure that the objectives of the energy efficiency plan are met and the energy audits’ recommendations are followed up and implemented.

The level of detail of the energy efficiency plan and audits will generally be related to the nature, scale and complexity of the plant.

b

General energy-saving techniques

These include techniques such as:

• heat recovery with heat exchangers and/or heat pumps;

• energy-efficient motors;

• frequency converters on motors;

• process control systems;

• combined heat and power generation (cogeneration);

• insulation of pipes, vessels and other equipment;

• combustion regulation and control;

• feed water preheating (including the use of economisers);

• minimisation of the blowdown of boilers;

• optimisation of steam distribution systems;

• reduction of compressed air system leaks;

• lighting management systems;

• energy-efficient lighting;

• optimisation of design and operation of cooling system(s).

Applicability of cogeneration to existing plants may be restricted by a suitable heat demand and/or by the plant layout/lack of space.

Management, design and operation techniques

a

Water management plan and water audits

A water management plan and water audits are part of the environmental management system (see BAT 1) and include:

• flow diagrams and water mass balances of the plant and processes as part of the inventory of inputs and outputs mentioned BAT 2;

• establishment of water efficiency objectives;

• implementation of water optimisation techniques (e.g. control of water usage, reuse/recycling, detection and repair of leaks).

Water audits are carried out at least once every year to ensure that the objectives of the water management plan are met and the water audits’ recommendations are followed up and implemented.

The level of detail and nature of the water management plan and water audits will generally be related to the nature, scale and complexity of the plant.

b

Segregation of water streams

Water streams that do not need treatment (e.g. uncontaminated cooling water, uncontaminated run-off water) are segregated from waste water that has to undergo treatment, thus enabling uncontaminated water recycling.

Applicability to existing plants may be restricted by the layout of the water collection system and the lack of space for temporary storage tanks.

c

Water reuse and/or recycling

Recycling and/or reuse of water streams (preceded or not by water treatment), e.g. for cleaning, washing, cooling or for the process itself.

May not be applicable due to hygiene and safety requirements.

d

Optimisation of water flow

Use of control devices, e.g. photocells, flow valves, thermostatic valves, to automatically adjust the water flow to the minimum amount needed.

Generally applicable.

e

Optimisation and appropriate use of water nozzles and hoses

Use of correct number and position of nozzles; adjustment of water pressure of nozzles and hoses.

Techniques related to cleaning operations

f

Dry cleaning

Removal of as much residual material as possible from raw materials and equipment, e.g. by using compressed air, vacuum systems or catchpots with a mesh cover.

Generally applicable.

g

High-pressure cleaning

Spraying of cleaning water at pressures ranging from 15 bar to 150 bar.

May not be applicable due to health and safety requirements.

h

Optimisation of chemical dosing and water use in cleaning-in-place (CIP)

The amounts of hot water and chemicals used are optimised by measuring for example turbidity, conductivity, temperature and/or pH.

Generally applicable.

i

Low-pressure foam and/or gel cleaning

Use of low-pressure foam and/or gel to clean walls, floors and/or equipment surfaces.

j

Optimised design and construction of equipment and process areas

The equipment and process areas are designed and constructed in a way that facilitates cleaning. When optimising the design and construction, hygiene requirements are taken into account.

k

Prompt cleaning of equipment

Cleaning is applied as soon as possible after use of equipment to prevent hardening of residual material.

a

Proper selection of cleaning chemicals and/or disinfectants

Avoidance or minimisation of the use of cleaning chemicals and/or disinfectants that are harmful to the aquatic environment, in particular those that contain priority substances considered under the Water Framework Directive⁽¹⁾.

When selecting the cleaning chemicals and/or disinfectants, hygiene and food safety requirements are taken into account.

This technique is part of the CMS (see BAT 3).

b

Reuse of cleaning chemicals in cleaning-in-place (CIP)

Collection and reuse of cleaning chemicals in CIP. When reusing cleaning chemicals, hygiene and food safety requirements are taken into account.

c

Dry cleaning

See BAT 10 (f).

d

Optimised design and construction of equipment and process areas

See BAT 10 (j).

a

Minimisation of biological degradation of animal by-products and/or edible co-products

Animal by-products and/or edible co-products are promptly collected in slaughterhouses and are stored in closed vessels or rooms in SA installations, for as short a time as possible, before further treatment. Raw materials intended for human consumption (e.g. fat, blood), feed material or pet food may require refrigeration.

Generally applicable.

b

Residues separation and recycling/recovery

Residues are separated, e.g. using accurately positioned screens, flaps, catchpots, drip trays and troughs, for recycling and recovery.

c

Anaerobic digestion

Treatment of biodegradable residues by microorganisms in the absence of oxygen, resulting in the generation of biogas and digestate. The biogas is used as a fuel, e.g. in a gas engine or in a boiler. The digestate may be used, e.g. as a soil improver, on site or off site.

May not be applicable due to the quantity and/or nature of the residues.

d

Phosphorus recovery as struvite

See Section 1.4.1.

Only applicable to waste water streams with a high total phosphorus content (e.g. above 50 mg/l) and a significant flow.

Preliminary, primary and general treatment

a

Equalisation

All pollutants

Generally applicable.

b

Neutralisation

Acids, alkalis

c

Physical separation, e.g. screens, sieves, grit separators, fat separators, primary settlement tanks

Gross solids, suspended solids, oil/grease

Physico-chemical treatment

d

Precipitation

Precipitable dissolved non-biodegradable or inhibitory pollutants, e.g. metals

Generally applicable.

e

Chemical oxidation (e.g. with ozone)

Reducible dissolved non-biodegradable or inhibitory pollutants, e.g. AOX, antimicrobial-resistant bacteria

Aerobic and/or anaerobic treatment (secondary treatment)

f

Aerobic and/or anaerobic treatment (secondary treatment), e.g. activated sludge process, aerobic lagoon, anaerobic contact process, membrane bioreactor

Biodegradable organic compounds

Generally applicable.

Nitrogen removal

g

Nitrification and/or denitrification

Total nitrogen, ammonium/ammonia

Nitrification may not be applicable in the case of high chloride concentrations (e.g. above 10 g/l).

Nitrification may not be applicable when the temperature of the waste water is low (e.g. below 12 °C).

Phosphorus removal

h

Precipitation

Total phosphorus

Generally applicable.

i

Enhanced biological phosphorus removal

j

Phosphorus recovery as struvite

Only applicable to waste water streams with a high total phosphorus content (e.g. above 50 mg/l) and a significant flow.

Final solids removal

k

Coagulation and flocculation

Suspended solids and particulate-bound non-biodegradable or inhibitory pollutants

Generally applicable.

l

Sedimentation

m

Filtration (e.g. sand filtration, microfiltration, ultrafiltration, reverse osmosis)

n

Flotation

Chemical oxygen demand (COD)⁽³⁾

mg/l

25–100 ^{(4) (5)}

Total organic carbon (TOC)⁽³⁾

7–35 ^{(5) (6)}

Total suspended solids (TSS)

4–30 ^{(5) (7) (8)}

Total nitrogen (Total N)

2–25 ^{(5) (9) (10)}

Total phosphorus (Total P)

0,25–2 ⁽⁵⁾

Adsorbable organically bound halogens (AOX)⁽¹¹⁾

0,02–0,3

Metals

Copper (Cu)⁽¹¹⁾

0,01–0,2 ⁽¹²⁾

Zinc (Zn)⁽¹¹⁾

0,05–0,5 ⁽¹²⁾

Adsorbable organically bound halogens (AOX)⁽³⁾

mg/l

0,02–0,3

Metals

Copper (Cu)⁽³⁾

0,01–0,2 ⁽⁴⁾

Zinc (Zn)⁽³⁾

0,05–0,5 ⁽⁴⁾

a

Optimisation of thermal oxidation or combustion in boilers

Optimisation of design and operation of boilers or thermal oxidisers to promote the oxidation of organic compounds, as well as to reduce the generation of pollutants such as NOX and CO.

CO, NOX

Generally applicable.

b

Removal of high levels of dust, NOX and SOX precursors

Removal (if possible, for reuse) of high levels of dust, NOX and SOX precursors prior to combustion of malodorous gases or thermal oxidation, e.g. by condensation. Additional post-combustion removal of dust, NOX and SOX may be carried out using wet scrubbing for example.

Dust, NOX, SOX

c

Fuel choice

The use of fuel (including support/auxiliary fuel) with a low content of potential pollution-generating compounds (e.g. low sulphur, ash, nitrogen, fluorine or chlorine content in the fuel).

Dust, NOX, SOX

d

Low-NOX burner

The technique is based on the principles of reducing peak flame temperatures. The air/fuel mixing reduces the availability of oxygen and reduces the peak flame temperature, thus retarding the conversion of fuel-bound nitrogen to NOX and the formation of thermal NOX, while maintaining high combustion efficiency. This may be associated with a modified design of the furnace combustion chamber.

NOX

Applicability to existing plants may be restricted by design and/or operational constraints.

Dust

mg/Nm³

< 1–5 ⁽¹⁾

NOX

50–200 ^{(1) (2)}

SOX

6–100

CO

mg/Nm³

3–30

a

Appropriate location of equipment and buildings

Increasing the distance between the emitter and the receiver, by using buildings as noise screens and by relocating equipment and/or buildings’ exits or entrances.

For existing plants, the relocation of equipment and buildings’ exits or entrances may not be applicable due to lack of space and/or excessive costs.

b

Operational measures

These include techniques such as:

1. inspection and maintenance of equipment;

2. closing of doors and windows of enclosed areas, if possible;

3. equipment operation by experienced staff;

4. avoidance of noisy activities at night, if possible;

5. provisions for noise control, e.g. during production and maintenance activities;

6. limitation of noise from animals in slaughterhouses (e.g. through careful transport and handling).

Generally applicable.

c

Low-noise equipment

This includes techniques such as low-noise compressors, pumps and fans.

d

Noise control equipment

This includes techniques such as:

1. noise reducers;

2. acoustic insulation of equipment;

3. enclosure of noisy equipment;

4. soundproofing of buildings.

May not be applicable to existing plants due to lack of space.

e

Noise abatement

Inserting obstacles between emitters and receivers (e.g. protection walls, embankments).

Generally applicable.

a.

Regular cleaning of installations and equipment

Regular cleaning (e.g. daily) of installations and equipment including areas where animal by-products and/or edible co-products are stored and processed.

Generally applicable.

b.

Cleaning and disinfection of vehicles and equipment used to transport and deliver animal by-products and/or edible co-products

Transport vehicles and delivery equipment (e.g. containers) are cleaned and disinfected after being emptied.

c.

Enclosure of animal by-products and/or edible co-products during transport, reception, loading/unloading and storage

Loading/unloading and reception areas are situated in enclosed ventilated buildings. Appropriate equipment is used for transport and storage of the animal by-products and/or edible co-products.

May not be applicable to existing plants due to lack of space.

d.

Minimisation of biological degradation of animal by-products and/or edible co-products

See BAT 12 (a).

Generally applicable.

e.

Air extraction as close as possible to the point of odour generation.

Air extraction as close as possible to the point of odour generation with full or partial enclosure. Extracted air may be treated (see BAT 25).

Generally applicable.

a

Refrigeration management plan

See Section 1.4.3.

Generally applicable.

b

Techniques for efficient scalding of pigs and/or poultry

These include techniques such as:

• steam scalding of pigs;

• immersion scalding of pigs and/or poultry with optimised water flow systems.

Applicability to existing plants may be restricted by the plant layout/lack of space.

Cattle

kWh/tonne of carcasses

116–240 ⁽³⁾

kWh/animal

30–80 ⁽⁴⁾

Pigs

kWh/tonne of carcasses

65–370 ⁽⁵⁾

kWh/animal

4–35 ⁽⁵⁾

Chickens

kWh/tonne of carcasses

170–490 ⁽⁵⁾

kWh/animal

0,25–0,90 ⁽⁵⁾

a

Dry emptying of cattle/pig stomachs

Cattle/pig stomachs are emptied by using machines without water.

Generally applicable.

b

Dry collection of the contents of pigs’ small intestines

Pigs’ small intestines are emptied by pulling them between a pair of rollers. Their content is collected in a tray and pumped to a container.

c

Techniques for efficient scalding

See BAT 21 (b).

Applicability to existing plants may be restricted by the plant layout/lack of space.

Cattle

m³/tonne of carcasses

1,85–3,90 ⁽³⁾

m³/animal

0,30–1,30 ⁽⁴⁾

Pigs

m³/tonne of carcasses

0,70–3,50

m³/animal

0,07–0,30

Chickens

m³/tonne of carcasses

1,45–6,30

m³/animal

0,002–0,013

a

Refrigeration management plan

See Section 1.4.3.

b

Preventive and corrective maintenance

The correct operation of the refrigeration equipment is regularly reviewed and any deviations/malfunctions are corrected/fixed in a timely manner.

c

Use of refrigerant leak detectors

A centralised alarm system is used in order to promptly identify refrigerant leaks.

Any type of refrigerant

Percentage (%) of the total amount of refrigerant contained in the cooling system(s)

< 1–5

Rendering, fat melting, blood and/or feather processing

kWh/tonne of raw material

120–910

Fishmeal and fish oil production

420–710

Gelatine manufacturing

1 380–2 500 ⁽¹⁾

Rendering, fat melting, blood and/or feather processing

m³/tonne of raw material

0,2–1,55

Fishmeal and fish oil production

0,20–1,25 ⁽¹⁾

Gelatine manufacturing

16,5–27 ⁽²⁾

a.

Condensation

See Section 1.4.2. The technique is used together with one or a combination of the techniques (b) to (g) for the treatment of non-condensable gases.

b.

Adsorption

See Section 1.4.2.

c.

Biofilter

d.

Combustion in a steam boiler of malodorous gases, including non-condensable gases

e.

Thermal oxidation

f.

Wet scrubber

g.

Bioscrubber

Odour concentration

ouE/m³

200–1 100 ^{(1) (2)}

TVOC

mg C/Nm³

0,5–16

NH3

mg/Nm³

0,1–4 ⁽³⁾

H2S

< 0,1–1 ⁽⁴⁾

Odour concentration

ouE/m³

400–3 500 ⁽¹⁾

TVOC⁽²⁾

mg C/Nm³

1–14

NH3 ⁽²⁾

mg/Nm³

0,1–7

Activated sludge process

A biological process in which the microorganisms are maintained in suspension in the waste water and the whole mixture is mechanically aerated. The activated sludge mixture is sent to a separation facility from where the sludge is recycled to the aeration tank.

Aerobic lagoon

Shallow earthen basin for the biological treatment of waste water, the content of which is periodically mixed to allow oxygen to enter the liquid through atmospheric diffusion.

Anaerobic contact process

An anaerobic process in which waste water is mixed with recycled sludge and then digested in a sealed reactor. The water/sludge mixture is separated externally.

Chemical oxidation (e.g. with ozone)

Chemical oxidation is the conversion of pollutants by chemical-oxidising agents other than oxygen/air or bacteria into similar but less harmful or hazardous compounds and/or to short-chained and more easily degradable or biodegradable organic components. Ozone is one example of a chemical-oxidising agent applied.

Coagulation and flocculation

Coagulation and flocculation are used to separate suspended solids from waste water and are often carried out in successive steps. Coagulation is carried out by adding coagulants with charges opposite to those of the suspended solids. Flocculation is carried out by adding polymers, so that collisions of microfloc particles cause them to bond to produce larger flocs.

Equalisation

Balancing of flows and pollutant loads by using tanks or other management techniques.

Enhanced biological phosphorus removal

A combination of aerobic and anaerobic treatment to selectively enrich polyphosphate-accumulating microorganisms in the bacterial community within the activated sludge. These microorganisms take up more phosphorus than is required for normal growth.

Filtration

The separation of solids from waste water by passing it through a porous medium, e.g. sand filtration, microfiltration and ultrafiltration.

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.

Membrane bioreactor

A combination of activated sludge treatment and membrane filtration. Two variants are used: a) an external recirculation loop between the activated sludge tank and the membrane module; and b) immersion of the membrane module in the aerated activated sludge tank, where the effluent is filtered through a hollow fibre membrane, with the biomass remaining in the tank.

Neutralisation

The adjustment of the pH of waste water to a neutral level (approximately 7) by the addition of chemicals. Sodium hydroxide (NaOH) or calcium hydroxide (Ca(OH)2) is generally used to increase the pH, whereas sulphuric acid (H2SO4), hydrochloric acid (HCl) or carbon dioxide (CO2) is generally used to decrease the pH. The precipitation of some substances may occur during neutralisation.

Nitrification and/or denitrification

A two-step process that is typically incorporated into biological waste water treatment plants. The first step is the aerobic nitrification where microorganisms oxidise ammonium (NH4 ⁺) to the intermediate nitrite (NO2 ^-), which is then further oxidised to nitrate (NO3 ^-). In the subsequent anoxic denitrification step, microorganisms chemically reduce nitrate to nitrogen gas.

Phosphorus recovery as struvite

Phosphorus contained in waste water streams is recovered by precipitation in the form of struvite (magnesium ammonium phosphate).

Precipitation

The conversion of dissolved pollutants into insoluble compounds by adding chemical precipitants. The solid precipitates formed are subsequently separated by sedimentation, air flotation, or filtration. Multivalent metal ions (e.g. calcium, aluminium, iron) are used for phosphorus precipitation.

Sedimentation

The separation of suspended particles by gravitational settling.

Adsorption

Organic compounds are removed from a waste gas stream by retention on a solid surface (typically activated carbon).

Bag filter

Bag filters, often referred to as fabric filters, are constructed from porous woven or felted fabric through which gases are passed to remove particles. The use of a bag filter requires the selection of a fabric suitable for the characteristics of the waste gas and the maximum operating temperature.

Biofilter

The waste gas stream is passed through a bed of organic material (such as peat, heather, compost, root, tree bark, softwood and different combinations) or some inert material (such as clay, activated carbon, and polyurethane), where it is biologically oxidised by naturally occurring microorganisms into carbon dioxide, water, inorganic salts and biomass.

A biofilter is designed considering the type(s) of waste input. An appropriate bed material, e.g. in terms of water retention capacity, bulk density, porosity, structural integrity, is selected. Also important are an appropriate height and surface area of the filter bed. The biofilter is connected to a suitable ventilation and air circulation system in order to ensure a uniform air distribution through the bed and a sufficient residence time of the waste gas inside the bed.

Biofilters can be divided into open-top biofilters and enclosed biofilters.

Bioscrubber

A packed tower filter with inert packing material which is normally continuously moistened by sprinkling water. Air pollutants are absorbed in the liquid phase and subsequently degraded by microorganisms settling on the filter elements.

Combustion in a steam boiler of malodorous gases, including non-condensable gases

Malodorous gases, including non-condensable gases, are burned in a steam boiler in the installation.

Condensation

The removal of vapours of organic and inorganic compounds from a process off-gas or waste gas stream by reducing its temperature below its dew point so that the vapours liquefy.

Thermal oxidation

The oxidation of combustible gases and odorants in a waste gas stream by heating the mixture of contaminants with air or oxygen to above its auto-ignition point in a combustion chamber and maintaining it at a high temperature long enough to complete its combustion to carbon dioxide and water.

Wet scrubber

The removal of gaseous or particulate pollutants from a gas stream via mass transfer to a liquid solvent, often water or an aqueous solution. It may involve a chemical reaction (e.g. in an acid or alkaline scrubber). In some cases, the compounds may be recovered from the solvent.

Refrigeration management plan

A refrigeration management plan is part of the environmental management system (see BAT 1) and entails:

• monitoring of energy consumption of the refrigeration system (see BAT 6);

• operational measures such as inspection and maintenance of equipment, closing of doors when possible; equipment operation by experienced staff;

• monitoring of refrigerant losses (see BAT 6).