Term used

Definition

Biochemical oxygen demand (BODn)

Amount of oxygen needed for the biochemical oxidation of the organic matter to carbon dioxide in n days (n is typically 5 or 7). BOD is an indicator for the mass concentration of biodegradable organic compounds.

Channelled emissions

Emissions of pollutants into the environment through any kind of duct, pipe, stack, etc.

Chemical oxygen demand (COD)

Amount of oxygen needed for the total chemical oxidation of the organic matter to carbon dioxide using dichromate. COD is an indicator for the mass concentration of organic compounds.

Dust

Total particulate matter (in air).

Existing plant

A plant that is not a new plant.

Hexane

Alkane of six carbon atoms, with the chemical formula C6H14.

hl

Hectolitre (equal to 100 litres).

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 following the publication of these BAT conclusions.

NOX

The sum of nitrogen monoxide (NO) and nitrogen dioxide (NO2), expressed as NO2.

Residue

Substance or object generated by the activities covered by the scope of this document, as waste or by-product.

SOX

The sum of sulphur dioxide (SO2), sulphur trioxide (SO3), and sulphuric acid aerosols, expressed as SO2.

Sensitive receptor

Areas which need special protection, such as:

Total nitrogen (TN)

Total nitrogen, expressed as N, includes free ammonia and ammonium nitrogen (NH4-N), nitrite nitrogen (NO2-N), nitrate nitrogen (NO3-N) and organically bound nitrogen.

Total organic carbon (TOC)

Total organic carbon, expressed as C (in water), includes all organic compounds.

Total phosphorus (TP)

Total phosphorus, expressed as P, includes all inorganic and organic phosphorus compounds, dissolved or bound to particles.

Total suspended solids (TSS)

Mass concentration of all suspended solids (in water), measured via filtration through glass fibre filters and gravimetry.

Total volatile organic carbon (TVOC)

Total volatile organic carbon, expressed as C (in air).

Averaging period

Definition

Average over the sampling period

Average value of three consecutive measurements of at least 30 minutes each  (3).

where:

hexane losses is the total amount of hexane consumed by the installation for each type of seeds or beans, expressed in kg/year;

raw materials is the total amount of each type of cleaned seeds or beans processed, expressed in tonnes/year.

where:

Waste water discharge is the total amount of waste water discharged (as direct discharge, indirect discharge and/or land spreading) by the specific processes concerned during the production period, expressed in m3/year, excluding any cooling water and run-off water that is discharged separately.

Activity rate is the total amount of products or raw materials processed, depending on the specific sector, expressed in tonnes/year or hl/year. Packaging is not included in the weight of the product. Raw material is any material entering the plant, treated or processed for the production of food or feed.

where:

Final energy consumption is the total amount of energy consumed by the specific processes concerned during the production period (in the form of heat and electricity), expressed in MWh/year.

Activity rate is the total amount of products or raw materials processed, depending on the specific sector, expressed in tonnes/year or hl/year. Packaging is not included in the weight of the product. Raw material is any material entering the plant, treated or processed for the production of food or feed.

Substance/parameter

Standard(s)

Minimum monitoring frequency  (5)

Monitoring associated with

Chemical oxygen demand (COD)  (6)  (7)

No EN standard available

Once every day  (8)

BAT 12

Total nitrogen (TN)  (6)

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

Total organic carbon (TOC)  (6)  (7)

EN 1484

Total phosphorus (TP)  (6)

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

Total suspended solids (TSS)  (6)

EN 872

Biochemical oxygen demand (BODn)  (6)

EN 1899-1

Once every month

Chloride (Cl-)

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

Once every month

—

Substance/Parameter

Sector

Specific process

Standard(s)

Minimum monitoring frequency  (9)

Monitoring associated with

Dust

Animal feed

Drying of green fodder

EN 13284-1

Once every three months  (10)

BAT 17

Grinding and pellet cooling in compound feed manufacture

Once every year

BAT 17

Extrusion of dry pet food

Once every year

BAT 17

Brewing

Handling and processing of malt and adjuncts

Once every year

BAT 20

Dairies

Drying processes

Once every year

BAT 23

Grain milling

Grain cleaning and milling

Once every year

BAT 28

Oilseed processing and vegetable oil refining

Handling and preparation of seeds, drying and cooling of meal

Once every year

BAT 31

Starch production

Drying of starch, protein and fibre

BAT 34

Sugar manufacturing

Drying of beet pulp

Once every month  (10)

BAT 36

PM2.5 and PM10

Sugar manufacturing

Drying of beet pulp

EN ISO 23210

Once every year

BAT 36

TVOC

Fish and shellfish processing

Smoke chambers

EN 12619

Once every year

BAT 26

Meat processing

Smoke chambers

BAT 29

Oilseed processing and vegetable oil refining  (11)

—

—

Sugar manufacturing

High-temperature drying of beet pulp

Once every year

—

NOX

Meat processing  (12)

Smoke chambers

EN 14792

Once every year

—

Sugar manufacturing

High-temperature drying of beet pulp

CO

Meat processing  (12)

Smoke chambers

EN 15058

Sugar manufacturing

High-temperature drying of beet pulp

SOX

Sugar manufacturing

Drying of beet pulp when natural gas is not used

EN 14791

Twice every year  (10)

BAT 37

Technique

Description

(a)

Energy efficiency plan

An energy efficiency plan, as part of the environmental management system (see BAT 1), 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. The plan is adapted to the specificities of the installation.

(b)

Use of common techniques

Common techniques include techniques such as:

Technique

Description

Applicability

Common techniques

(a)

Water recycling and/or reuse

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 food safety requirements.

(b)

Optimisation of water flow

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

(c)

Optimisation of water nozzles and hoses

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

(d)

Segregation of water streams

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

The segregation of uncontaminated rainwater may not be applicable in the case of existing waste water collection systems.

Techniques related to cleaning operations

(e)

Dry cleaning

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

Generally applicable.

(f)

Pigging system for pipes

Use of a system made of launchers, catchers, compressed air equipment, and a projectile (also referred to as a ‘pig’, e.g. made of plastic or ice slurry) to clean out pipes. In-line valves are in place to allow the pig to pass through the pipeline system and to separate the product and the rinsing water.

(g)

High-pressure cleaning

Spraying of water onto the surface to be cleaned 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)

Optimising the design of CIP and measuring turbidity, conductivity, temperature and/or pH to dose hot water and chemicals in optimised quantities.

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)

Cleaning of equipment as soon as possible

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

Technique

Description

(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 priority substances considered under the Water Framework Directive 2000/60/EC of the European Parliament and of the Council (13)

When selecting the substances, hygiene and food safety requirements are taken into account.

(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 7e.

(d)

Optimised design and construction of equipment and process areas

See BAT 7j.

Technique

Description

Applicability

(a)

Anaerobic digestion

Treatment of biodegradable residues by microorganisms in the absence of oxygen, resulting in 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.

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

(b)

Use of residues

Residues are used, e.g. as animal feed.

May not be applicable due to legal requirements.

(c)

Separation of residues

Separation of residues, e.g. using accurately positioned splash protectors, screens, flaps, catchpots, drip trays and troughs.

Generally applicable.

(d)

Recovery and reuse of residues from the pasteuriser

Residues from the pasteuriser are fed back to the blending unit and are thereby reused as raw materials.

Only applicable to liquid food products.

(e)

Phosphorus recovery as struvite

See BAT 12g.

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

(f)

Use of waste water for land spreading

After appropriate treatment, waste water is used for land spreading in order to take advantage of the nutrient content and/or to use the water.

Only applicable in the case of a proven agronomic benefit, a proven low level of contamination and no negative impact on the environment (e.g. on the soil, the groundwater and surface water).

The applicability may be restricted due to the limited availability of suitable land adjacent to the installation.

The applicability may be restricted by the soil and local climatic conditions (e.g. in the case of wet or frozen fields) or by legislation.

Technique  (14)

Typical pollutants targeted

Applicability

Preliminary, primary and general treatment

(a)

Equalisation

All pollutants

Generally applicable.

(b)

Neutralisation

Acids, alkalis

(c)

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

Gross solids, suspended solids, oil/grease

Aerobic and/or anaerobic treatment (secondary treatment)

(d)

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

Biodegradable organic compounds

Generally applicable.

Nitrogen removal

(e)

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).

(f)

Partial nitritation — Anaerobic ammonium oxidation

May not be applicable when the temperature of the waste water is low.

Phosphorus recovery and/or removal

(g)

Phosphorus recovery as struvite

Total phosphorus

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

(h)

Precipitation

Generally applicable.

(i)

Enhanced biological phosphorus removal

Final solids removal

(j)

Coagulation and flocculation

Suspended solids

Generally applicable.

(k)

Sedimentation

(l)

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

(m)

Flotation

Parameter

BAT-AEL  (15)  (16) (daily average)

Chemical oxygen demand (COD)  (17)  (18)

25-100 mg/l  (19)

Total suspended solids (TSS)

4-50 mg/l  (20)

Total nitrogen (TN)

2-20 mg/l  (21)  (22)

Total phosphorus (TP)

0,2-2 mg/l  (23)

Technique

Description

Applicability

(a)

Appropriate location of equipment and buildings

Noise levels can be reduced by increasing the distance between the emitter and the receiver, by using buildings as noise screens and by relocating 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:

Generally applicable.

(c)

Low-noise equipment

This includes low-noise compressors, pumps and fans.

(d)

Noise control equipment

This includes:

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 and buildings).

Applicable only to existing plants, as the design of new plants should make this technique unnecessary. For existing plants, the insertion of obstacles may not be applicable due to lack of space.

Product

Unit

Specific energy consumption

(yearly average)

Compound feed

MWh/tonne of products

0,01-0,10 (24)  (25)  (26)

Dry pet food

0,39-0,50

Wet pet food

0,33-0,85

Technique

Description

Applicability

(a)

Use of predried fodder

Use of fodder that has been predried (e.g. by flat pre-wilting).

Not applicable in the case of the wet process.

(b)

Recycling of waste gas from the dryer

Injection of the waste gas from the cyclone into the burner of the dryer.

Generally applicable.

(c)

Use of waste heat for predrying

The heat of the outlet steam from the high-temperature dryers is used for predrying part or all of the green fodder.

Product

Unit

Specific waste water discharge

(yearly average)

Wet pet food

m3/tonne of products

1.3-2.4

Technique

Description

Applicability

a

Bag filter

See Section 14.2.

May not be applicable to the abatement of sticky dust.

b

Cyclone

Generally applicable.

Parameter

Specific process

Unit

BAT-AEL

(average over the sampling period)

New plants

Existing plants

Dust

Grinding

mg/Nm3

< 2-5

< 2-10

Pellet cooling

< 2-20

Technique

Description

Applicability

(a)

Mashing-in at higher temperatures

The mashing-in of the grain is carried out at temperatures of approximately 60 °C, which reduces the use of cold water.

May not be applicable due to the product specifications.

(b)

Decrease of the evaporation rate during wort boiling

The evaporation rate can be reduced from 10 % down to approximately 4 % per hour (e.g. by two-phase boiling systems, dynamic low-pressure boiling).

(c)

Increase of the degree of high-gravity brewing

Production of concentrated wort, which reduces its volume and thereby saves energy.

Unit

Specific energy consumption

(yearly average)

MWh/hl of products

0,02-0,05

Unit

Specific waste water discharge

(yearly average)

m3/hl of products

0,15-0,50

Technique

Description

(a)

Recovery and (re)use of yeast after fermentation

After fermentation, yeast is collected and can be partially reused in the fermentation process and/or may be further used for multiple purposes, e.g. as animal feed, in the pharmaceutical industry, as a food ingredient, in an anaerobic waste water treatment plant for biogas production.

(b)

Recovery and (re)use of natural filter material

After chemical, enzymatic or thermal treatment, natural filter material (e.g. diatomaceous earth) may be partially reused in the filtration process. Natural filter material can also be used, e.g. as a soil improver.

Parameter

Unit

BAT-AEL

(average over the sampling period)

New plants

Existing plants

Dust

mg/Nm3

< 2-5

< 2-10

Technique

Description

(a)

Partial milk homogenisation

The cream is homogenised together with a small proportion of skimmed milk. The size of the homogeniser can be significantly reduced, leading to energy savings.

(b)

Energy-efficient homogeniser

The homogeniser’s working pressure is reduced through optimised design and thus the associated electrical energy needed to drive the system is also reduced.

(c)

Use of continuous pasteurisers

Flow-through heat exchangers are used (e.g. tubular, plate and frame). The pasteurisation time is much shorter than that of batch systems.

(d)

Regenerative heat exchange in pasteurisation

The incoming milk is preheated by the hot milk leaving the pasteurisation section.

(e)

Ultra-high-temperature (UHT) processing of milk without intermediate pasteurisation

UHT milk is produced in one step from raw milk, thus avoiding the energy needed for pasteurisation.

(f)

Multi-stage drying in powder production

A spray-drying process is used in combination with a downstream dryer, e.g. fluidised bed dryer.

(g)

Precooling of ice-water

When ice-water is used, the returning ice-water is precooled (e.g. with a plate heat exchanger), prior to final cooling in an accumulating ice-water tank with a coil evaporator.

Main product (at least 80 % of the production)

Unit

Specific energy consumption (yearly average)

Market milk

MWh/tonne of raw materials

0,1-0,6

Cheese

0,10-0,22  (27)

Powder

0,2-0,5

Fermented milk

0,2-1,6

Main product (at least 80 % of the production)

Unit

Specific waste water discharge (yearly average)

Market milk

m3/tonne of raw materials

0,3-3,0

Cheese

0,75-2,5

Powder

1,2-2,7

Technique

Description

Techniques related to the use of centrifuges

(a)

Optimised operation of centrifuges

Operation of centrifuges according to their specifications to minimise the rejection of product.

Techniques related to butter production

(b)

Rinsing of the cream heater with skimmed milk or water

Rinsing of the cream heater with skimmed milk or water which is then recovered and reused, before the cleaning operations.

Techniques related to ice cream production

(c)

Continuous freezing of ice cream

Continuous freezing of ice cream using optimised start-up procedures and control loops that reduce the frequency of stoppages.

Techniques related to cheese production

(d)

Minimisation of the generation of acid whey

Whey from the manufacture of acid-type cheeses (e.g. cottage cheese, quark and mozzarella) is processed as quickly as possible to reduce the formation of lactic acid.

(e)

Recovery and use of whey

Whey is recovered (if necessary using techniques such as evaporation or membrane filtration) and used, e.g. to produce whey powder, demineralised whey powder, whey protein concentrates or lactose. Whey and whey concentrates can also be used as animal feed or as a carbon source in a biogas plant.

Technique

Description

Applicability

(a)

Bag filter

See Section 14.2.

May not be applicable to the abatement of sticky dust.

(b)

Cyclone

Generally applicable.

(c)

Wet scrubber

Parameter

Unit

BAT-AEL (average over the sampling period)

Dust

mg/Nm3

< 2-10  (28)

Technique

Description

(a)

Removal of fat and viscera by vacuum

Use of vacuum suction instead of water to remove fat and viscera from the fish.

(b)

Dry transport of fat, viscera, skin and fillets

Use of conveyors instead of water.

Technique

Description

(a)

Biofilter

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

(b)

Thermal oxidation

See Section 14.2.

(c)

Non-thermal plasma treatment

(d)

Wet scrubber

See Section 14.2.

An electrostatic precipitator is commonly used as a pre-treatment step.

(e)

Use of purified smoke

Smoke generated from purified primary smoke condensates is used to smoke the product in a smoke chamber.

Parameter

Unit

BAT-AEL (average over the sampling period)

TVOC

mg/Nm3

15–50  (29)  (30)

Specific process

Unit

Specific energy consumption (yearly average)

Potato processing (excluding starch production)

MWh/tonne of products

1,0-2,1  (31)

Tomato processing

0,15-2,4  (32)  (33)

Specific process

Unit

Specific waste water discharge (yearly average)

Potato processing (excluding starch production)

m3/tonne of products

4,0-6,0  (34)

Tomato processing when water recycling is possible

8,0-10,0  (35)

Unit

Specific energy consumption (yearly average)

MWh/tonne of products

0,05-0,13

Parameter

Unit

BAT-AEL (average over the sampling period)

Dust

mg/Nm3

< 2-5

Unit

Specific energy consumption

(yearly average)

MWh/tonne of raw materials

0,25-2,6  (36)  (37)

Unit

Specific waste water discharge(yearly average)

m3/tonne of raw materials

1,5-8,0  (38)

Technique

Description

(a)

Adsorption

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

(b)

Thermal oxidation

See Section 14.2.

(c)

Wet scrubber

See Section 14.2.

An electrostatic precipitator is commonly used as a pretreatment step.

(d)

Use of purified smoke

Smoke generated from purified primary smoke condensates is used to smoke the product in a smoke chamber.

Parameter

Unit

BAT-AEL

(average over the sampling period)

TVOC

mg/Nm3

3-50  (39)  (40)

Specific process

Unit

Specific energy consumption

(yearly average)

Integrated crushing and refining of rapeseeds and/or sunflower seeds

MWh/tonne of oil produced

0,45-1,05

Integrated crushing and refining of soybeans

0,65-1,65

Stand-alone refining

0,1-0,45

Specific process

Unit

Specific waste water discharge (yearly average)

Integrated crushing and refining of rapeseeds and/or sunflower seeds

m3/tonne of oil produced

0,15-0,75

Integrated crushing and refining of soybeans

0,8-1,9

Stand-alone refining

0,15-0,9

Technique

Description

Applicability

(a)

Bag filter

See Section 14.2.

May not be applicable to the abatement of sticky dust.

(b)

Cyclone

Generally applicable.

(c)

Wet scrubber

Parameter

Unit

BAT-AEL

(average over the sampling period)

New plants

Existing plants

Dust

mg/Nm3

< 2-5  (41)

< 2-10  (41)

Technique

Description

(a)

Countercurrent flow of meal and steam in the desolventiser-toaster

Hexane is removed from the hexane-laden meal in a desolventiser-toaster, involving a countercurrent flow of steam and meal.

(b)

Evaporation from the oil/hexane mixture

Hexane is removed from the oil/hexane mixture using evaporators. The vapours from the desolventiser-toaster (steam/hexane mixture) are used to provide thermal energy in the first stage of the evaporation.

(c)

Condensation in combination with a mineral oil wet scrubber

Hexane vapours are cooled to below their dew point so that they condense. Uncondensed hexane is absorbed in a scrubber using mineral oil as a scrubbing liquid for subsequent recovery.

(d)

Gravitational phase separation in combination with distillation

Undissolved hexane is separated from the aqueous phase by means of a gravitational phase separator. Any residual hexane is distilled off by heating the aqueous phase to approximately 80-95 °C.

Parameter

Type of seeds or beans processed

Unit

BAT-AEL

(yearly average)

Hexane losses

Soybeans

kg/tonne of seeds or beans processed

0,3-0,55

Rapeseeds and sunflower seeds

0,2-0,7

Technique

Description

Applicability

(a)

Single pasteuriser for nectar/juice production

Use of one pasteuriser for both the juice and the pulp instead of using two separate pasteurisers.

May not be applicable due to the pulp particle size.

(b)

Hydraulic sugar transportation

Sugar is transported to the production process with water. As some of the sugar is already dissolved during the transportation, less energy is needed in the process for dissolving sugar.

Generally applicable.

(c)

Energy-efficient homogeniser for nectar/juice production

See BAT 21b.

Unit

Specific energy consumption

(yearly average)

MWh/hl of products

0,01-0,035

Unit

Specific waste water discharge (yearly average)

m3/hl of products

0,08-0,20

Specific process

Unit

Specific energy consumption (yearly average)

Potato processing for the production of native starch only

MWh/tonne of raw materials  (42)

0,08-0,14

Maize and/or wheat processing for the production of native starch in combination with modified and/or hydrolysed starch

0,65-1,25  (43)

Specific process

Unit

Specific waste water discharge (yearly average)

Potato processing for the production of native starch only

m3/tonne of raw materials  (44)

0,4-1,15

Maize and/or wheat processing for the production of native starch in combination with modified and/or hydrolysed starch

1,1-3,9  (45)

Technique

Description

Applicability

(a)

Bag filter

See Section 14.2.

May not be applicable to the abatement of sticky dust.

(b)

Cyclone

Generally applicable.

(c)

Wet scrubber

Parameter

Unit

BAT-AEL (average over the sampling period)

New plants

Existing plants

Dust

mg/Nm3

< 2-5  (46)

< 2-10  (46)

Technique

Description

Applicability

(a)

Pressing of beet pulp

The beet pulp is pressed to a dry matter content of typically 25-32 wt-%.

Generally applicable.

(b)

Indirect drying (steam drying) of beet pulp

Drying of beet pulp by the use of superheated steam.

May not be applicable to existing plants due to the need for a complete reconstruction of the energy facilities.

(c)

Solar drying of beet pulp

Use of solar energy to dry beet pulp.

May not be applicable due to local climatic conditions and/or lack of space.

(d)

Recycling of hot gases

Recycling of hot gases (e.g. waste gases from the dryer, boiler or combined heat and power plant).

Generally applicable.

(e)

Low-temperature (pre)drying of beet pulp

Direct (pre)drying of beet pulp using drying gas, e.g. air or hot gas.

Specific process

Unit

Specific energy consumption (yearly average)

Sugar beet processing

MWh/tonne of beets

0,15-0,40  (47)

Specific process

Unit

Specific waste water discharge (yearly average)

Sugar beet processing

m3/tonne of beets

0,5-1,0

Technique

Description

Applicability

(a)

Use of gaseous fuels

See Section 14.2.

May not be applicable due to the constraints associated with the availability of gaseous fuels.

(b)

Cyclone

Generally applicable.

(c)

Wet scrubber

(d)

Indirect drying (steam drying) of beet pulp

See BAT 35b.

May not be applicable to existing plants due to the need for a complete reconstruction of the energy facilities.

(e)

Solar drying of beet pulp

See BAT 35c.

May not be applicable due to local climatic conditions and/or lack of space.

(f)

Low-temperature (pre)drying of beet pulp

See BAT 35e.

Generally applicable.

Parameter

Unit

BAT-AEL (average over the sampling period)

Reference oxygen level (OR)

Reference gas condition

Dust

mg/Nm3

5-100

16 vol-%

No correction for water content

Technique

Description

Applicability

(a)

Use of natural gas

—

May not be applicable due to the constraints associated with the availability of natural gas.

(b)

Wet scrubber

See Section 14.2.

Generally applicable.

(c)

Use of fuels with low sulphur content

—

Only applicable when natural gas is not available.

Parameter

Unit

BAT-AEL

(average over the sampling period)  (48)

Reference oxygen level (OR)

Reference gas condition

SOX

mg/Nm3

30-100

16 vol-%

No correction for water content

Technique

Description

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 basins 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.

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.

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.

Partial nitritation — Anaerobic ammonium oxidation

A biological process that converts ammonium and nitrite into nitrogen gas under anaerobic conditions. In waste water treatment, anaerobic ammonium oxidation is preceded by a partial nitrification (i.e. nitritation) that converts about half of the ammonium (NH4 +) into nitrite (NO2 -).

Phosphorus recovery as struvite

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

Sedimentation

The separation of suspended particles by gravitational settling.

Upflow anaerobic sludge blanket (UASB) process

An anaerobic process in which waste water is introduced at the bottom of the reactor from where it flows upward through a sludge blanket composed of biologically formed granules or particles. The waste water phase passes into a settling chamber where the solid content is separated; the gases are collected in domes at the top of the reactor.

Technique

Description

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.

Cyclone

Dust control system based on centrifugal force, whereby heavier particles are separated from the carrier gas.

Non-thermal plasma treatment

Abatement technique based on creating a plasma (i.e. an ionised gas consisting of positive ions and free electrons in proportions resulting in more or less no overall electric charge) in the waste gas by using a strong electrical field. The plasma oxidises organic and inorganic compounds.

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.

Use of gaseous fuels

Switching from the combustion of a solid fuel (e.g. coal) to the combustion of a gaseous fuel (e.g. natural gas, biogas) that is less harmful in terms of emissions (e.g. low sulphur content, low ash content or better ash quality).

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.