Feedstocks for pulp production include wood as well as non-wood materials such as wheat straws, reed, and bamboo. The major types of pulp and paper mills are as follows (EC 2001):

• Kraft or sulfate pulp and paper mills account for about 80% of world pulp production;
• Sulfite pulp and paper mills account for about 10% of world production;
• Mechanical pulp and paper mills; and
• Recycled fiber paper mills.

Pulp and paper production processes may release PCDD/PCDF to these vectors:

• Releases to air from energy generation;
• Releases to water in wastewater treatment effluents;
• Releases to residue as wastewater treatment sludge and ashes or smelt; and
• Releases to product – pulp and paper.

In general terms, the process of making paper and paperboard consists of three steps: pulp making, pulp processing, and paper/paperboard making. A detailed description of the process is available in the BAT&BEP Guidelines.

Emission Factors

PCDD/PCDF emission factors for on-site heat/power production are listed in Table II.7.3 and those for other pulp and paper production processes are presented according to the activity type in Tables II.7.4 and II.7.5. Revised or newly added emission factors are highlighted in red. Detailed information on the derivation of emission factors can be found in Annex 47.

Table II.7.3 PCDD/PCDF emission factors for source category 7a Power Boilers in the Pulp and Paper Industry

7a	Pulp and Paper Industry	EFAir µg TEQ/ADtA	EFResidue µg TEQ/ashB
Classification
1	Recovery boilers fueled with black liquor	0.03	ND
2	Power boilers fueled with sludge and/or biomass/bark	0.5	5
3	Power boilers fueled with salt-laden wood	13	228

^A Air-Dried tons
^B Bottom ash or bottom ash plus fly ash

Table II.7.4 PCDD/PCDF emission factors for source category 7a Wastewater Effluent from Pulp and Paper Production and Pulp Sludges

7a	Pulp and Paper Production	EFWater Wastewater effluent		EFResidue Sludge
	Classification	µg TEQ/ADt pulp	pg TEQ/L	µg TEQ/ADt pulp	µg TEQ/t Sludge
1	Kraft process, Cl2, non-wood, PCP-contaminated fibers	ND	300*	ND	ND
2	Kraft process, Cl2	4.5	70	4.5	100
3	Mixed technology (Cl2 partially in 1st step, followed by non-chlorine bleaching)	1.0	15	1.5	30
4	Sulfite process, Cl2	ND	ND	ND	ND
5	Kraft process, ClO2	0.06	2	0.2	10
6	Sulfite process, either ClO2 or totally chlorine-free (TCF)	ND	ND	ND	ND
7	Thermo-mechanical process, lignin-saving chemical treatment	ND	ND	ND	ND
8	Paper recycling with contaminated waste paper	ND	30**	ND	ND
9	Paper recycling with modern paper	ND	ND	ND	ND

* Raw effluent
** Wastewater from deinking system

Table II.7.5 PCDD/PCDF emission factors for source category 7a Pulp and Paper Products

7a	Pulp and Paper Production	EFProduct
	Classification	µg TEQ/t product
1	Kraft process, Cl2, non-wood, PCP-contaminated fibers	30
2	Kraft process, Cl2	10
3	Mixed technology (Cl2 partially in 1st step, followed by non-chlorine bleaching)	3
4	Sulfite process, Cl2	1
5	Kraft process, ClO2	0.5
6	Sulfite process, either ClO2 or totally chlorine-free (TCF)	0.1
7	Thermo-mechanical process, lignin-saving chemical treatment	1
8	Paper recycling with contaminated waste paper	10
9	Paper recycling with modern paper	3

* Raw effluent
** Wastewater from deinking system

Guidance for classification of sources

On-site boilers for heat/power generation for the pulp and paper production are classified as follows:

Class 1 Recovery boilers fired with black liquor or black liquor/bio-sludge (for sludge for modern bleaching technology).
Class 2 Power boilers fired with sludge and biomass/bark.
Class 3 Power boilers fired with salt-laden wood.

Processes for producing pulp and paper are placed in the following classes:

Class 1 facilities use the Kraft process for pulping non-wood fibers that are potentially contaminated with PCP and bleach with Cl2.
Class 2 facilities use the Kraft process for pulping fibers that are PCP-free and bleach with Cl2.
Class 3 facilities use the Kraft process for pulping and bleach first with Cl2, followed by non-chlorine bleaching technologies.
Class 4 facilities use the sulfite process for pulping and bleach with Cl2.
Class 5 facilities use the Kraft process for pulping and bleach with chlorine dioxide (ClO2).
Class 6 facilities use the sulfite process for pulping and bleach with ClO2 or with totally chlorine-free (TCF) technologies.
Class 7 facilities use thermo-chemical processes to produce pulp and bleach via lignin-saving methods that use sodium dithionite (Na2S2O3), peroxide (H2O2) or a mixture of these two chemicals.
Class 8 facilities are those engaged in recycling paper from contaminated waste paper – paper that is made from pulp produced by Class 1 through Class 4 facilities.
Class 9 facilities are those engaged in recycling paper from modern paper – paper derived from pulp produced by Class 5 and Class 7 facilities.

To assist in estimating PCDD/PCDF releases, typical PCDD/PCDF values are given in terms of tons of air-dried pulp and paper produced (ADt), with pulp at 90% dryness and paper as the finished paper, which typically has 94-96% dryness. Typical PCDD/PCDF concentrations in effluent, residues and products are also presented for use when mass production data are not available. Emission factors for all wood fiber mills (classes 2-7) are based on the assumption that all such mills have wastewater treatment facilities that produce sludge and effluent low in suspended solids.

Level of confidence

Emission factors for this source category are associated with a medium level of confidence for all classes, as they are based on a few reported data from a limited number of experiments with a limited geographical coverage, but not requiring expert judgment.

For groups 7b through 7h, the following definitions of classes should be applied:

Guidance for classification of sources

Low-end technologies: No information available, or processes (reactions, purification steps and wastewater and waste treatment) are not controlled in respect to the formation of PCDD/PCDF or other unintentional POPs. Chemical feedstocks, air emissions, wastewater, residues and products are not monitored for PCDD/PCDF, other unintentional POPs or indicator substances.
Mid-range technologies: Processes (reactions and purifications steps including prevention by process- and production-integrated measures and wastewater and waste treatment) are controlled to some extent to limit releases. Parameters of these processes (e.g. feedstock; temperature; presence or use of chlorine in some form and, if, used, its concentration) are also controlled to reduce formation and release of unintentional POPs. Process inputs and emissions to air, wastewater, residues and products are monitored to some extent for PCDD/PCDF, other unintentional POPs or indicator substances.
High-end technologies: Processes (reactions and purifications steps including prevention by process- and production-integrated measures and wastewater and waste treatment) are optimized for low or no releases. Parameters of these processes (e.g. feedstock; temperature; presence or use of chlorine in some form and, if, used, its concentration) are optimized for minimum formation and release of unintentional POPs. Chemicals, products or by-products, emissions to air, wastewater and residues are monitored for PCDD/PCDF, other unintentional POPs or indicator substances. A refining step is used where appropriate to minimize unintentional POPs in the final chemical, product or by-product. Process residues should be handled in an environmentally sound manner, as described in the guidance on the BAT and BEP.

Elemental Chlorine (Cl2)

Production of Cl2 (CAS 7782-50-5) is the first step in producing chemicals and consumer goods that contain chlorine, as well as those for which some form of chlorine is used during their production. Global production of Cl2 was estimated to be 81.2 million tons per year in 2012 (CMAI 2011a) and its uses, on a worldwide basis, are as follows (Beal and Linak 2011):

• Almost 35% is used in the EDC/VCM/PVC production chain – production of ethylene dichloride (EDC), which is used to make vinyl chloride (VCM) that is polymerized to produce polyvinyl chloride (PVC);
• 15% is used in the manufacture of isocyanates and propylene oxide, both of which are building blocks for polyurethane;
• 20% is used to produce other organic derivatives;
• 20% is used in the production of inorganic chemicals; and
• The remaining 10% is used in a variety of processes, such as water and wastewater treatment.

Uses of Cl2 vary greatly by country and region. In the chlor-alkali process, Cl2 and caustic soda [sodium hydroxide (NaOH)] are produced in a mass ratio of 1:1.1 by the electrolysis of brine (sodium chloride). Factors that can influence PCDD/PCDF formation and release in the chlor-alkali process include process design and direct contact of Cl2 with reactive materials, such as graphite electrodes and certain seals, gaskets, lubricants, etc.

Electrodes made of graphite, a form of elemental carbon, which often included tar as binder pitch, were widely used until the 1970s when, in many countries, they were replaced by titanium electrodes. Due in part to their contribution to PCDD/PCDF formation and release, graphite electrodes are not considered Best Available Technique (BAT). Limited data show that far lower levels of PCDF may also be formed when titanium electrodes are used, perhaps through reactions of elemental chlorine with reactive gaskets and seals (USEPA 2004).

More detailed descriptions of the three main chlor-alkali processes are presented in the BAT&BEP Guidelines.

Emission Factors

Emission factors are derived for four classes of Cl2 production via the chlor-alkali process: one class that uses graphite electrodes without regard for equipment and operational standards, and three classes that use titanium electrodes. Revised or newly added emission factors are highlighted in red.

Table II.7.6 PCDD/PCDF emission factors for source category 7b Elemental Chlorine Production

7a	Elemental chlorine (Cl2)	Emission Factors (µg TEQ/ECU*)
	Classification	Air	Water	Land	Product	Residue
1.	Chlorine/chlor-alkali production using graphite electrodes	ND	ND	ND	ND	20,000 µg TEQ/t sludge 1,000 µg TEQ/ECU
2. Chlorine/chlor-alkali production using titanium electrodes
2a	Low-end technologies	ND	17	ND	ND	27
2b	Mid-range technologies	ND	1.7 120 pg TEQ/L	ND	ND	1.7
2c	High-end technologies	ND	0.002	ND	ND	0.3

* Electrochemical unit (ECU) consists of 1 ton of chlorine and 1.1 tons of caustic soda (NaOH)

Level of Confidence

Emission factors in this section are associated with a low level of confidence for all classes since they are based on a low data range with limited geographical coverage.

Ethylene Dichloride (EDC), Vinyl Chloride Monomer (VCM) and Polyvinyl Chloride (PVC)

Approximately 35% of global production of elemental chlorine is consumed by the production of ethylene dichloride (EDC) (CAS 107-06-2), vinyl chloride monomer (VCM) (CAS 75-01-4) and polyvinyl chloride (PVC) (CAS 9002-86-2) (Beal and Linak 2011). EDC is used almost exclusively for producing VCM and VCM is used almost exclusively in the production of PVC resin (Nexant 2009). In 2009, worldwide production of PVC was estimated at 32.3 million tons per year (GBI 2011).

PVC is produced by two major pathways:

• The EDC/VCM/PVC production chain uses ethylene derived from petroleum or natural gas as its primary feedstock and accounts for about two-thirds of global PVC production; and
• The acetylene/VCM/PVC production chain which uses acetylene derived from coal as the primary feedstock and accounts for the remaining one-third of global PVC production (CMAI 2011b).

The EDC/VCM/PVC production chain consists of five major processes:

1. EDC production
   • Direct chlorination of ethylene using elemental chlorine in the presence of an iron catalyst; and/or
   • Oxychlorination of ethylene using hydrogen chloride (HCl) and air or oxygen in the presence of a copper catalyst;
2. Purification of EDC;
3. VCM production via thermal cracking of EDC, which also produces HCl that may be recycled into the oxychlorination process;
4. Purification of VCM; and
5. PVC production via polymerization of VCM.

Oxychlorination of ethylene to produce EDC has been described as the most favorable process step in the chemical industry for the formation of PCDD/PCDF (UNEP 2005). However, PCDD/PCDF are also known to occur in other processes in the EDC/VCM/PVC production chain (Weiss and Kandle 2006).

Within the EDC/VCM/PVC chain, most EDC production is a balanced mix of direct chlorination and oxychlorination, although some sites are direct chlorination only, or oversized for oxychlorination. Most EDC production is integrated with VCM production on the same site. However, some facilities produce only EDC and ship it elsewhere, and, perhaps more commonly, VCM production facilities ship their VCM elsewhere for polymerization into PVC. PCDD/PCDF can be released to one or more vectors from the production of EDC, VCM, and PVC, as detailed in Annex 48.

The acetylene/VCM/PVC production chain entails the following major processes:

1. VCM production via the reaction of acetylene with HCl in the presence of a mercuric chloride catalyst;
2. Purification of VCM; and
3. Polymerization of VCM to form PVC.

The acetylene/VCM/PVC production chain is largely used in China, where it accounts for 81% of total PVC production capacity (CMAI 2011b). Little information is available on PCDD/PCDF releases from this production chain other than limited data on releases from acetylene production (Lee et al. 2009, Jin et al. 2009) and in wastewater treatment sludge (USEPA 2000a). More detailed descriptions of EDC, VCM and PVC production processes are given in Annex 48 and in the BAT&BEP Guidance.

Emission Factors

Emission factors for production of EDC, VCM and PVC are presented in Tables II.7.7-II.7.10, according to four types of facilities – EDC/VCM/PVC facilities, EDC/VCM facilities, EDC-only facilities and PVC-only facilities. Revised or newly added emission factors are highlighted in red.

The derivation of emission factors presented in Tables II.7.7-II7.10 is explained in Annex 48. As parties and facilities evaluate their operations they should note that any facility may have a mixture of classes of operation. Generally, analytical data should be required to support a claim of class 3.

For on-site hazardous waste incinerators and boilers used to generate heat and power, relevant information should be gathered and included in Source Group 1 – Waste Incineration and Source Group 3 – Power Generation and Heating, respectively.

Table II.7.7 PCDD/PCDF emission factors (EFAir) for source category 7c EDC/VCM/PVC Production: Releases to Air from Vent or Liquid/Vent Combustors or Thermal Oxidizers and Halogen Acid Furnaces

7c EDC, VCM and PVC Production	EDC, EDC/VCM and EDC/VCM/PVC Vent and Liquid-Vent Combustors or Thermal Oxidizers		PVC-Only Vent Combustors or Thermal Oxidizers		Halogen Acid Furnaces
		Flue Gas Conc.		Flue Gas Conc.	Flue Gas Conc.
Classification	µg TEQ/t VCM	ng TEQ/Nm³	µg TEQ/t PVC	ng TEQ/Nm³	ng TEQ/Nm³
1. Low-end technologies	5	5	1	1	0.5
2. Mid-range technologies	0.5	0.5	0.1	0.1	0.06
3. High-end technologies	0.05	0.1	0.02	0.02	0.02

Table II.7.8 PCDD/PCDF emission factors (EFWater) for source category 7c EDC/VCM/PVC Production: Releases to Water via Wastewater Effluent

7c EDC, VCM and PVC Production	EDC, EDC/VCM and EDC/VCM/PVC production from sites with oxychlorination reactorsA		Suspension, Dispersion or Emulsion PVC-only
		Concentration		Concentration
Classification	µg TEQ/t EDC	ng TEQ/L	µg TEQ/t PVC	ng TEQ/L
1. Low-end technologies	25	5	0.3	0.01
2. Mid-range technologies	2.5	0.5	0.03	0.001
3. High-end technologies	0.5	0.1	0.003	0.0001

^A Assumes a balanced or nearly balanced direct chlorination-oxychlorination process. Sites operating direct chlorination only are ND.

Table II.7.9 PCDD/PCDF emission factors (EFResidue) for source category 7c EDC/VCM/PVC Production: Releases to Residues

7c EDC, VCM and PVC Production	EDC, EDC/VCM, and EDC/VCM/PVC Facilities µg TEQ/t EDC from sites with oxychlorination reactorsA			PVC-only µg TEQ/t PVC
	Waste Water Treatment Solids		Spent Catalyst	Waste Water Treatment Solids
Classification	Fixed-bedB	Fluidized-bedC	Fixed-bedB
1. Low-end technologies	0.75	4	8	0.095
2. Mid-range technologies	0.2	2	0.85	0.06
3a. High-end technologies (if solids are incinerated)	NA
3b. High-end technologies (if solids are not incinerated)	0.095	0.4	0.02	0.005

^A Assumes a balanced or nearly balanced direct chlorination-oxychlorination process. Sites operating direct chlorination only are ND.
^B Solids derived from an EDC facility utilizing a fixed-bed oxychlorination catalyst
^C Solids derived from an EDC facility utilizing a fluidized-bed oxychlorination catalyst

Table II.7.10 PCDD/PCDF emission factors (EFProduct) for source category 7c EDC/VCM/PVC Production: Releases to Products

7c EDC, VCM and PVC Production	µg TEQ/t EDC, VCM or PVC sold
	EDC		VCM	PVC
Classification	Produced by oxychlorination or mixed direct chlorination and oxychlorination	Produced by Direct chlorination only
1. Low-end technologies	2	ND	NA	ND
2. Mid-range technologies	0.2	ND	NA	ND
3. High-end technologies	0.006	ND	NA	NA

Level of confidence

Emission factors in this source category are associated with a low level of confidence for all classes, as emission factors are based on a low data range derived from a limited geographical coverage.

Chlorobenzenes

Chlorobenzenes are produced commercially by reacting Cl2 with liquid benzene in the presence of a catalyst such as ferric chloride (FeCl3). The predominant products of this reaction are chlorobenzene, HCl, 1,2-dichlorobenzene (o-dichlorobenzene) (CAS 95-50-1) and 1,4-dichlorobenzene (p-dichlorobenzene) (CAS 106-46-7). As this direct chlorination process is continued, 1,2,4-trichlorobenzene (CAS 120-82-1), other tri-, tetra-, and pentachlorobenzenes, and, finally, hexachlorobenzene are formed. Total global production of chlorobenzenes in 2003 is estimated at 640,000 tons (China Chemical Reporter 2004).

For 1,4-dichlorobenzene, the largest use may be in the production of poly(p-phenylene) sulfide, a thermoplastic polymer in wide use because of its resistance to chemical and thermal attack. It is also used as an insecticide to control moths, moulds, mildew, and as a disinfectant and odor control agent in waste containers and restrooms (Rossberg et al. 2006).

Emission Factors

A default emission factor is shown in Table II.7.11 for 1,4-Dichlorobenzene, and further details on its derivation are presented in Annex 48.

Table II.7.11 PCDD/PCDF emission factors for source category 7d Chlorobenzene Production

7d	Chlorobenzene Production	Emission Factors (µg TEQ/t product)
	Classification	Air	Water	Land	Product	Residue
1	1,4-Dichlorobenzene (1,4-DCB, p-dichlorobenzene or p-DCB)	ND	ND	NA	39	ND

Level of confidence

The emission factor is associated with a medium level of confidence, as it is based on a low data range; it is not based on expert judgment, but derived from a limited geographical coverage.

Polychlorinated Biphenyls (PCBs)

The total global production of PCBs is estimated at 1.3 to 2 million tons (Breivik et al. 2002, Fiedler 2001). PCBs have been used for a wide range of closed applications (transformers, capacitors) and open applications (sealants, caulking, carbonless paper, plasticizers in paints and cements, casting agents, flame retardant in fabric and heat stabilizing additives for PVC electrical insulation, adhesives, railway sleepers) (Erickson and Kaley 2011). Although PCB production ceased in the 1980s, much PCB-containing equipment remains in use, materials containing PCBs are being used, and PCB wastes are still awaiting disposal.

PCDD/PCDF in commercial PCBs consist mainly of PCDF in the μg/kg to mg/kg range, along with low PCDD concentrations (Takasuga et al. 2005, Huang et al. 2011, Johnson et al. 2008, Wakimoto et al. 1988). The global production of 1.3 to 2 million tons PCBs contained approximately 10,400 to 16,000 kg WHO-TEQ mainly from dioxin-like PCBs (Weber et al. 2008a,b). PCDD/PCDF concentrations in used PCBs are largely unknown. Limited data are available on PCDF levels in used PCBs, indicating that, for transformers, the levels might be similar as those found in used PCBs (Huang et al. 2011, Masuda et al. 1986). As shown in Table II.10.1, the dioxin-like TEQ contribution from PCDF in technical PCBs is normally below 10%. When commercial PCBs are subjected to elevated temperatures, PCDD/PCDF concentrations increase as documented for heat exchange fluids in the Yusho incident, where PCDF TEQ levels had considerably increased, reaching similar TEQ levels as for dl-PCB (Masuda et al. 1986). PCDF formation by thermal treatment of PCB can result in a TEQ increase of the PCB mixture of up to 50 fold (Weber 2007). Sites where PCBs are used or PCB-containing equipment is stored, dismantled or disposed of can generate local contamination and potential hotspots (see Source Group 10).

The first step in estimating the stock and releases of PCDD/PCDF associated with the use and storage of PCB-containing equipment is to compile a national inventory of the equipment and possibly other PCB legacies. Based on the PCB inventory, total TEQ in this stock can be calculated according to Table II.10.2. The inventory data can be used in combination with PCB leakage rates to estimate the quantity of PCDD/PCDF and dioxin-like PCBs released annually from the inventoried PCB equipment. The PCB leakage rates depend on a number of factors including the age of the equipment, conditions of exploitation and storage, climatic conditions etc. The precise impact of most of these factors is not well studied. For a preliminary assessment of PCB releases into the environment, emission factors given in the EMEP/EEA Atmospheric Emission Inventory Guidebook (2009) can be used (Table II.10.1). Local circumstances will determine whether the leaked PCBs and PCDD/PCDF are released to air, water or land or sent to disposal.

Pentachlorophenol (PCP) and Sodium Pentachlorophenate (PCP-Na)

PCP or “penta” (CAS 87-86-5) and PCP-Na (CAS 131-52-2) are used as pesticides and as preservatives for e.g. wood (indoor and outdoor), leather, textiles (including cotton or wool) and for killing snails in areas where schistosomiasis is epidemic (Zheng et al. 2008, 2011). PCP is also used to produce PCP-Na and pentachlorophenol laurate (PCPL), which is used on textiles and other fabrics (van der Zande 2010).

While there are no recent data on global production, PCP production is estimated at 7,257 tons/year in the U.S. (van der Zande 2010). In 2010, Mexico produced approximately 7,000 tons/year, approximately 80% of which were exported (B. Cardenas, personal communication, 26 November 2012). In China, PCP production was of 10,000 tons/year in 1997 (Ge et al. 2007). PCP is produced by several methods, including the following:

Reaction of Cl2 with liquid phenol, chlorophenol or a polychlorophenol at 30-40°C to produce 2,4,6-trichlorophenol, which is then converted to PCP by further chlorination at progressively higher temperatures in the presence of catalysts (aluminum, antimony, their chlorides, and others) (Borysiewicz 2008);

Alkaline hydrolysis of hexachlorobenzene (HCB) in methanol and dihydric alcohols, in water and mixtures of different solvents in an autoclave at 130 - 170°C (Borysiewicz 2008); and

Thermolysis of hexachlorocyclohexane (HCH), including a chlorination step and hydrolysis (Wu 1999).

PCP-Na was produced until 1984 using the alkaline hydrolysis of hexachlorobenzene. Now, however, it is produced by dissolving PCP flakes in sodium hydroxide solution (Borysiewicz 2008). It has been suggested that post-production processing of PCP flakes from the latter process accounted for more extensive exposure to PCP and its contaminants than did production (Ruder 2011).

PCDD/PCDF are by-products in all of these manufacturing methods (Borysiewicz 2008). In addition, the method based on alkaline hydrolysis of HCB can result in the presence of HCB in the resulting PCP. Commercial PCP may contain up to 0.1% of PCDD/PCDF, which are released to the air from PCP-treated products, released to water when PCP-treated textiles and other products are washed, and concentrated in the sludge of wastewater facilities that treat the washwater. PCP-derived PCDD/PCDF are released to air and land from in-service wood products, such as utility poles and railroad ties (Borysiewicz 2008), when sewage sludge is land applied, and when PCP-treated products are burned.

PCDD/PCDF may also be brought into a country through the import of PCP as well as PCP-treated products such as wood and wood products, furniture, textiles, and leather. Tracing these flows can be very difficult. The impact on emission factors of burning PCP-contaminated wood can be seen in source category 3d - Household Heating and Cooking with Biomass. PCP-treated materials also contribute to higher releases from open burning processes as can be seen in source category 6b - Waste Burning and Accidental Fires.

Emission Factors

Emission factors for PCP and PCP-Na are presented in Table II.7.14. Revised or newly added emission factors are highlighted in red. For the use of PCP for agricultural or related purposes, releases to land of PCDD/PCDF can be estimated by using the EFProduct as EFLand.

Table II.7.14 PCDD/PCDF emission factors for source category 7d PCP and PCP-Na Production

7d	PCP and PCP-Na Production	Emission Factors (µg TEQ/t product)
Classification		Air	Water	Land	Product	Residue
1	Pentachlorophenol (PCP)	ND	ND	ND	634,000	ND
2	Pentachlorophenol, sodium salt (PCP-Na)	ND	ND	ND	12,500	ND

Level of Confidence

Emission factors in this source category are associated with a medium level of confidence, as they are based on a low data range and are derived from a limited geographical coverage.

2,4,5-Trichlorophenoxyacetic Acid (2,4,5-T) and 2,4,6-Trichlorophenol

2,4,5-T (CAS 93-76-5), a herbicide used primarily as defoliant, is the most important derivative of 2,4,5-trichlorophenol (CAS 95-95-4). Today, there are only a few production sites of trichlorophenol. While 2,4,5-T is widely perceived as being contaminated with only 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD), substantial concentrations of other PCDD/PCDF congeners have been identified (Pignatello and Huang 1993).

Hotspots in soil that may exist at former 2,4,5-T production, storage and handling sites should be addressed in Source Group 10 – Contaminated Sites and Hotspots.

Emission Factors

Due to lack of data, emission factors have been derived only for releases in products, as shown in Table II.7.15. For the use of 2,4,5-T for agricultural or related purposes, releases to land of PCDD/PCDF can be estimated by using the EFProduct as EFLand.

Table II.7.15 PCDD/PCDF emission factors for source category 7d 2,4,5-T and 2,4,6-Trichlorophenol Production

7d	2,4,5-T and 2,4,6-Trichlorophenol Production	Emission Factors (µg TEQ/t product)
Classification		Air	Water	Land	Product	Residue
1	2,4,5-Trichlorophenoxyacetic acid (2,4,5-T)	ND	ND	ND	7,000	ND
2	2,4,6-Trichlorophenol	ND	ND	ND	700	ND

Level of confidence

Emission factors are associated with a medium level of confidence, as they are based on a low data range; they are not based on expert judgment, but are derived from a limited geographical coverage.

Chloronitrofen, Chlornitrofen, or 2,4,6-Trichlorophenyl-4-nitrophenylether (CNP)

CNP (CAS 1836-77-7) has been used as an alternative for pentachlorophenol and applied extensively in rice paddies in Japan. Production of CNP begins with the production of 2,4,6-trichlorophenol (CAS 88-06-2). 2,4,6-trichlorophenol is reacted with potassium hydroxide to form potassium 2,4,6-trichlorophenolate. The latter chemical is reacted with 4-fluoronitrobenzene in the presence of a copper catalyst to form 2,4,6-trichlorophenyl p-nitrophenyl ether (Suzuki and Nagao 2005).

Emission Factors

Due to insufficient information, only emission factors for releases in product were derived, as shown in Table II.7.16. Revised or newly added emission factors are highlighted in red. For the use of CNP for agricultural or related purposes, releases to land of PCDD/PCDF can be estimated by using the EFProduct as EFLand.

Table II.7.16 PCDD/PCDF emission factors for source category 7d CNP Production

7d	CNP Production	Emission Factors (µg TEQ/t product)
Classification		Air	Water	Land	Product	Residue
1	Low-end technologies	ND	ND	ND	9,200,000	ND
2	Mid-range technologies	ND	ND	ND	4,500	ND

Level of confidence

Emission factors are associated with a medium level of confidence, as they are based on a low data range; they are not based on expert judgment, but are derived from a limited geographical coverage.

Pentachloronitrobenzene (PCNB) (Quintozene)

PCNB (CAS 82-68-8), also known by other names including quintozene and terrachlor, is a broad-spectrum, contact fungicide used on a wide range of crops, such as turf, peanuts, cole crops (e.g., cabbage), rice, potatoes and cotton. It is used to treat both soil and seeds as well as for foliar application. However, due in part to PCDD/PCDF contamination, PCNB has been banned for a variety of uses in several countries, including the U.S., Canada, Japan and Germany.

PCNB is produced by the reaction in chlorosulfuric acid of nitrobenzene and Cl2 with iodine as a catalyst. PCNB can also be produced by the nitration of pentachlorobenzene.

High concentrations of PCDD/PCDF have been detected in studies conducted in Australia (Holt et al. 2010), China (Huang et al. 2012), and Japan (MAFF 2002). The latter two studies also found high concentrations of dioxin-like PCBs. In addition, a study of PCNB exposure to sunlight found that PCDD/PCDF TEQ increased by more than 800% (Holt et al. 2011).

Emission Factors

For the production of PCNB, PCDD/PCDF emission factors are shown in Table II.7.17 and PCB emission factors are shown in Annex 48. Revised or newly added emission factors are highlighted in red.

For the use of PCNB is for agricultural or related purposes, release to land of both PCDD/PCDF and PCBs can be estimated by using the EFProduct as EFLand. Similarly, for aquacultural or related purposes, release to water can be estimated by using the EFProduct as EFWater.

Table II.7.17 PCDD/PCDF emission factors for source category 7d Pentachloronitrobenzene Production

7d	Pentachloronitrobenzene Production	Emission Factors (µg TEQ/t product)
Classification		Air	Water	Land	Product	Residue
1	Low-end production technologies	ND	ND	ND	5,600	ND
2	Mid-range production technologies	ND	ND	ND	2,600	ND
3	High-end production technologies	ND	ND	ND	260	ND

Level of confidence

Emission factors in this section are associated with a medium level of confidence, as emission factors are based on a moderate data range with a broad geographical distribution.

2,4-Dichlorophenoxyacetic Acid (2,4-D) and Derivatives

2,4-Dichlorophenoxyacetic acid (2,4-D, CAS 94-75-7) and its derivatives are systemic herbicides used to control broadleaf weeds. 2,4-D is one of the world’s most widely used pesticides (Industry Task Force 2012).

2,4-D is commonly prepared by the condensation of 2,4-dichlorophenol with monochloroacetic acid in a strongly alkaline medium at moderate temperatures. It is also produced by the chlorination of phenoxyacetic acid, but this method leads to a product with a high content of 2,4-dichlorophenol and other impurities. Higher reaction temperatures and alkaline conditions during the manufacture of 2,4-D increase the formation of PCDD/F. The alkali metal salts of 2,4-D are produced by the reaction of 2,4-D with the appropriate metal base. Amine salts are obtained by reacting amine and 2,4-D in a compatible solvent. Esters are formed by acid-catalysed esterification with azeotropic distillation of water or by direct synthesis in which the appropriate ester of monochloroacetic acid is reacted with dichlorophenol to form the 2,4-D ester (IPCS 1989). The following include some of the more commonly used derivatives of 2,4-D: 2,4-D sodium salt (CAS 2702-72-9); 2,4-D diethyl amine (CAS 2008-39-1); 2,4-D dimethylamine salt (CAS 2008-39-1); 2,4-D isopropyl ester (CAS 94-11-1); 2,4-D triisopropyl acid; 2,4-D butoxyethyl ester (CAS 1929-73-3); 2,4-D isooctyl ester (CAS 25168-26-7); and 2,4-D ethylhexyl ester (CAS 1928-43-4). 2,4-D was first marketed in 1944. Off-patent for many years, 2,4-D and its derivatives are manufactured by many different companies around the world.

Emission Factors

For the production of 2,4-D and its derivatives, PCDD/PCDF emission factors are presented in Table II.7.18. Revised or newly added emission factors are highlighted in red.

For uses of 2,4-D and its derivatives for agricultural or related purposes, release to land can be estimated by using the EFProduct as EFLand. Similarly, for aquacultural uses, release to water can be estimated by using the EFProduct as EFWater.

Table II.7.18 PCDD/PCDF emission factors for source category 7d 2,4-D and Derivatives

7d	2,4-D and Derivatives	Emission Factors (µg TEQ/t product)
Classification		Air	Water	Land	Product	Residue
1	Low-end production technologies	ND	ND	ND	5,688	ND
2	Mid-range production technologies	ND	ND	ND	170	ND
3	High-end production technologies	ND	ND	ND	0.1	ND

Level of confidence

Emission factors in this section are associated with a medium level of confidence, as emission factors are based on a moderate data range with a broad geographical distribution.

More detailed information on PCDD/PCDF contamination of other organochlorine pesticides can be found in Annex 2.

Chlorinated Paraffins (CPs)

CPs are straight-chain hydrocarbons that have been chlorinated. Chlorinated paraffins are classified according to their carbon-chain length and percentage of chlorination, with carbon-chain lengths generally ranging from C10 to C30 and chlorination from approximately 35% to greater than 70% by weight. Around 40 CAS numbers have been used to describe the whole chlorinated paraffin family, e.g., CPs of unspecified length are CAS 63449-39-8.

CPs are made by reacting Cl2 with paraffin fractions obtained from petroleum distillation. The three most common commercial feedstocks used are short-chain (C10-13), medium-chain (C14-17) and long-chain (C18-30) paraffins. Global production of CPs is estimated at 1 million tons/yr, some 70% of which is produced in China (Takasuga et al. 2012). The largest use of CPs is in industrial cutting fluids, particularly in the manufacture of automobiles and automobile parts. In addition, they are used in commercial paints, adhesives, sealant and caulks as well as plasticizers in PVC and flame retardants in other plastics and rubber. Relatively high concentrations of PCDD/PCDF, total PCBs and HCB have been reported in samples of technical long-chain CPs (Takasuga et al. 2012).

Emission Factors

For the production of CPs, PCDD/PCDF emission factors are shown in Table II.7.19. Revised or newly added emission factors are highlighted in red. Emission factors for other unintentional POPs releases are presented in Annex 48.

Table II.7.19 PCDD/PCDF emission factors for source category 7d Chlorinated Paraffins Production

7d	Chlorinated Paraffins Production	Emission Factors (µg TEQ/t product)
Classification		Air	Water	Land	Product	Residue
1	Low-end production technologies	ND	ND	ND	ND	ND
2	Mid-range production technologies	ND	ND	ND	500	ND
3	High-end production technologies	ND	ND	ND	140	ND

Level of confidence

Emission factors in this section are associated with a low level of confidence, as emission factors are based on a small data range with a limited geographical distribution.

p-Chloranil (2,3,5,6-tetrachloro-2,5-cyclohexadiene-1,2-dione)

p-Chloranil (CAS 118-75-2) is used as an intermediate in the production of medicines, pesticides, and dioxazine dyes. It is also used as a fungicide and for seed treatment, although such uses are prohibited in some countries. In China, about 2,000 tons of chloranil are produced and used as a fungicide, as an intermediate in the synthesis of medicines and pesticides, and as an oxidizing agent used in organic synthesis, particularly for dye intermediates (Liu et al. 2012). Two methods for producing p-chloranil are as follows:

1. The process of direct chlorination of phenol using Cl2, which produces both o- and p-chloranil was developed and used in Germany until 1990. This may still be used by producers in other countries.
2. The more widely used process begins with the conversion of phenol to hydroquinone, followed by the reaction of hydroquinone with Cl2 or hydrogen peroxide and hydrochloric acid to form p-chloranil.

PCDD/PCDF contamination in chloranil is transferred to dyestuffs, pigments, inks, etc. and other products made from chloranil (see chloranil-derived pigments and dyes below). PCDD/PCDF in chloranil-derived materials are further transferred into the production processes of textiles, polymers/plastics, and packaging materials (paper, tin cans, etc.) and released in process outputs (see, for example, source category 7g – Textile Production). When textiles, clothing and other consumer goods treated with chloranil-based pigments and dyes are washed, some portion of the PCDD/PCDF is carried into domestic and municipal wastewater, where it contributes to PCDD/PCDF in wastewater treatment effluents and sludge. When the consumer goods are discarded or recycled, the PCDD/PCDF that originated during chloranil production adds to PCDD/PCDF contamination in disposal and recycling processes. In paper recycling and textile production and dyeing, PCDD/PCDF will be released into water and/or concentrated in the residue (sludge).

Emission Factors

Due to lack of data, emission factors for p-chloranil are derived only for releases to product. Revised or newly added emission factors are highlighted in red.

Table II.7.20 PCDD/PCDF emission factors for source category 7d p-Chloranil Production

7d	p-Chloranil Production	Emission Factors (µg TEQ/t product)
Classification		Air	Water	Land	Product	Residue
1	Direct chlorination of phenol	ND	ND	ND	400,000	ND
2	Chlorination of hydroquinone with minimal purification	ND	ND	ND	1,500,000	ND
3	Chlorination of hydroquinone with moderate purification	ND	ND	ND	26,000	ND
4	Chlorination of hydroquinone with advanced purification	ND	ND	ND	150	ND

Level of confidence

Emission factors are associated with a medium level of confidence, as they are based on a low data range; they are not based on expert judgment, but are derived from a limited geographical coverage.

Phthalocyanine dyes and pigments

Phthalocyanine dyes and pigments had a global production rate of about 420,000 tons in 2011 (Linak et al. 2011, The Freedonia Group 2009). They are prepared by variations of the following methods:

• Reaction of phthalonitrile with metal or metal salts;
• Reaction of phthalic anhydride, phthalic acid or phthalimide, tetrachlorophthalic anhydride with e.g. specific organics, urea, metal salt and catalyst;
• Reaction of metal-free phthalocyanine or replaceable metal phthalocyanine with another metal.

Copper phthalocyanine, a blue pigment, is generally produced using the second method. The phthalic anhydride/imide, a metal salt, urea and a catalyst are heated at 170-2000C for about four hours in a solvent such as trichlorobenzene, nitrobenzene or chloronaphthalene. The blue of copper phthalocyanine is shifted towards green by replacing hydrogen atoms on the aromatic rings with chlorine (e.g. pigment green 7) or chlorine and bromine (e.g. pigment green 36). This is accomplished through direct chlorination of copper phthalocyanine by passing Cl2 into an AlCl3/NaCl mixture at 180-200°C (Jain 2011). PCDD/PCDF have been detected in samples of copper phthalocyanine and phthalocyanine green (Ni et al. 2005), as well as nickel phthalocyanine (Hutzinger and Fiedler 1991).

Emission Factors

Due to lack of data, PCDD/PCDF emission factors for phthalocyanine-derived dyes and pigments are presented only for releases in products. Revised or newly added emission factors are highlighted in red. Emission factors for other unintentional POPs are included in Annex 48.

Table II.7.21 PCDD/PCDF emission factors for source category 7d Phthalocyanine Dyes and Pigments Production

7d	Phthalocyanine Dyes and Pigments Production	Emission Factors (µg TEQ/t product)
Classification		Air	Water	Land	Product	Residue
1	Phthalocyanine copper (CAS 147-14-8)	ND	ND	ND	70	ND
2	Phthalocyanine green (CAS 1328-45-6)	ND	ND	ND	1,400	ND

Tetrachlorophthalic acid (TCPA) and related pigments

TCPA is the primary feedstock for the production of a range of pigments. While no PCDD/PCDF data are available for TCPA, unintentional HCB concentrations as high as 3,000,000 µg/kg have been detected (Government of Japan 2006, 2007). Additional information on HCB concentrations in TCPA and corresponding emission factors are included in Annex 48.

Dioxazine dyes and pigments

Dioxazine dyes and pigments are produced through the reaction of p-chloranil with aromatic amines in the presence of a base. Tests on some of these dyes and pigments in the early 1990s showed PCDD/PCDF concentrations in the range 1 to 60 mg TEQ/kg, attributed to the use of PCDD/PCDF-contaminated p-chloranil produced by the chlorination of phenol (USEPA 2006a, Krizanec and Le Marechal 2006). Subsequently, an alternate process was developed for producing chloranil with lower PCDD/PCDF content through the reaction of hydroquinone with HCl. Dioxazine pigments and dyes made using the more contaminated chloranil are listed in Table II.7.22, along with their PCDD/PCDF content. Revised or newly added emission factors are highlighted in red.

Table II.7.22 PCDD/PCDF emission factors for source category 7d Dioxazine-Based Pigments Production

7d	Dioxazine-Based Pigments Production	Emission Factors (µg TEQ/t product)
Classification		Air	Water	Land	Product	Residue
1	Blue 106 (CAS 6527-70-4)	ND	ND	ND	35,000	ND
2	Blue 108 (CAS 1324-58-9)	ND	ND	ND	100	ND
3	Violet 23 (Carbazole violet) (CAS 6358-30-1)	ND	ND	ND	12,000	ND

Level of confidence

Emission factors are associated with a medium level of confidence, as they are based on a low data range; they are not based on expert judgment, but are derived from a limited geographical coverage.

Triclosan [5-chloro-2-(2,4-dichlorophenoxy)phenol]

Triclosan (CAS 3380-34-5), a chlorophenoxy derivative, is produced by the reaction of 2,4,4’-trichloro-2’-methoxydiphenyl ether with aluminum chloride in benzene. Triclosan is used globally as an antibacterial and antifungal agent in consumer products, including soaps, deodorants, toothpastes, shaving creams, mouth washes, and cleaning supplies. It is also infused in an increasing number of consumer products, such as kitchen utensils, toys, bedding, socks, and trash bags.

Emission Factors

Emission factors are derived for three classes of production of triclosan. Revised or newly added emission factors are highlighted in red.

Table II.7.23 PCDD/PCDF emission factors for source category 7d Triclosan Production

7d	Triclosan Production	Emission Factors (µg TEQ/t product)
Classification		Air	Water	Land	Product	Residue
1	Low-end production technologies	ND	ND	ND	1,700	82,000
2	Mid-range production technologies	ND	ND	ND	60	ND
3	High-end production technologies	ND	ND	ND	3	ND

Level of confidence

Emission factors are associated with a medium level of confidence, as they are based on a low data range; they are not based on expert judgment, but are derived from a limited geographical coverage.

Titanium Tetrachloride (TiCl4) and Titanium Dioxide (TiO2)

TiO2 (CAS 13463-67-7) is the world’s most widely used white pigment, with global production estimated to be 5 million tons in 2007 (USGS 2008). About 50% of TiO2 is used in paints, varnishes and lacquer; 25% in paper and paperboard; and 20% in plastics (USEPA 2001).

TiO2 is produced from TiO2-rich ores, such as rutile or ilmenite, by either of two processes:

• The sulfate process entails digesting ilmenite ore or TiO2-rich slag with sulfuric acid to produce a cake, which is purified and calcined to produce TiO2 pigment. This process is less commonly used because it generates sulfuric acid wastes in as much as two times the product weight, resulting in the need for expensive treatment by neutralization before disposal of the wastes (UNEP 2007, USEPA 1995).
• The chloride process entails reacting elemental chlorine with rutile or high-grade ilmenite at 850°C to 950°C, using petroleum coke as a reductant. This produces TiCl4 (CAS 7550-45-0) gas, which is then oxidized to form purified TiO2. The chloride process is most commonly used due to its relative compactness, recycling of process materials, better product properties, and considerably lower generation of waste (UNEP 2007, USEPA 1995).

PCDD/PCDF formation is known to occur in the chloride process (Lakshmanan et al. 2004), and PCDD/PCDF have been detected in treated wastewater, wastewater treatment sludge, and filter press solids (USEPA 2001).

Emission Factors

Emission factors are derived for TiO2 production via the chloride process and presented in Table II.7.24. Revised or newly added emission factors are highlighted in red.

Table II.7.24 PCDD/PCDF emission factors for source category 7e TiCl4 and TiO2 Production via the Chloride Process

7e	TiCl4 and TiO2 Production	Emission Factors (µg TEQ/t product)
Classification		Air	Water	Land	Product	Residue
1	Low-end production technologies	ND	0.2	ND	0	42
2	High-end production technologies	ND	0.001	ND	0	8

Level of confidence

Emission factors are associated with a medium level of confidence, as they are based on a low data range; they are not based on expert judgment, but are derived from a limited geographical coverage.

Caprolactam (2-Azacycloheptanone)

Caprolactam (CAS 105-60-2) is produced commercially by two methods. Only one entails the use of chlorine in some form: the reaction of HCl with nitrosylsulfuric acid to produce nitrosyl chloride which is then reacted with cyclohexane and HCl to produce cyclohexanone which undergoes further reactions to produce caprolactam. In 2010, global production of caprolactam was 3.8 million metric tons (SRI Consulting 2011). Virtually all caprolactam is used to produce Nylon 6. PCDD/PCDF have been detected in air emissions, process wastewater and in treated wastewater from caprolactam production facilities in two countries (Lee et al. 2009, Kawamoto 2002, Hong and Xu 2012). These findings suggest that PCDD/PCDF are likely also to occur in residues, including those from wastewater treatment.

Emission Factors

Table II.7.25 PCDD/PCDF emission factors for source category 7e Caprolactam Production

7e	Caprolactam Production	Emission Factors (µg TEQ/t product)
Classification		Air	Water	Land	Product	Residue
1	Caprolactam	0.00035	0.50 pg TEQ/L	ND	ND	ND

Level of confidence

Emission factors are associated with a medium level of confidence, as they are based on a low data range; they are not based on expert judgment, but are derived from a limited geographical coverage.

The petroleum refining industry converts crude oil into refined products, including liquefied petroleum gas, gasoline, kerosene, aviation fuel, diesel fuel, fuel oils, lubricating oils, bitumen and feedstock for the petrochemical industry. The composition of petroleum (crude oil) can vary significantly depending on its source.

Petroleum refining processes that have been identified as PCDD/PCDF sources include the following (RTI International 2011, Jacobs Consultancy 2002):

• Stationary combustion sources, such as boilers and process heaters, generate heat and power by burning fuels derived from refinery processes; these sources are addressed in Source Group 3 Power Generation and Heating. Particular attention is needed in the development of the PCDD/PCDF inventory for this source category to avoid double counting of releases from power boilers.
• Coking units use heat to thermally crack heavy hydrocarbon streams to form lighter, more useful distillates such as heating oils or gasoline. Traditional fluid coking units are one of the largest vent emissions sources at a refinery, being comparable to emissions from the CCU regenerator.
• Catalytic reforming units are a series of catalytic reactors that turn naphtha into high-octane gasoline. The catalyst accumulates carbon (coke) so that it must be regenerated. In the continuous process, aged catalyst is continuously moved from the reactor to the regenerator where the carbon is burned from the catalyst with hot air/steam. Chlorine or organochlorines , such as tri- or perchloroethylene, are added to retain catalytic activity. While the catalytic reactors have no direct process vents, the catalyst regenerators do have such vents.
• Flares are compulsory safety equipment used both for safety reasons during upsets, start-up, shut down, and system blow-down and for managing the disposal of waste gases from routine operations.

PCDD/PCDF may be released to air from vent stacks and flares, captured in scrubbing systems and released to water in treated effluents, and released in residues such as exhausted catalysts and wastewater treatment sludge.

Emission Factors

Emission factors for calculating releases of PCDD and PCDF from petroleum refineries are presented below for the following processes:

• Flaring of gases released from the petroleum industry
• Catalytic reforming unit (including catalyst regenerator)
• Coking unit
• Refinery-wide wastewater treatment.

PCDD/PCDF emission factors are listed in Tables II.7.26 and II.7.27. Revised or newly added emission factors are highlighted in red. Detailed information on the derivation of these emission factors can be found in Annex 49.

Table II.7.26 PCDD/PCDF emission factors for source category 7f Petroleum Refining (flaring of gases)

7f	Petroleum Refining (flares)	EFAir µg TEQ/TJ fuel burned
Classification
1	Flares	0.25

Table II.7.27 PCDD/PCDF emission factors for source category 7f Petroleum Refining (production processes)

7f	Petroleum Refining (production processes)	Emission Factors
Classification		Air mg TEQ/t oilA	Water pg TEQ/L	Land	Product	Residue mg TEQ/t residue
1	Catalytic reforming unit (including catalyst regenerator)	0.017	NA	NA	NA	14
2	Coking unit	0.41	NA	NA	NA	ND
3	Refinery-wide wastewater treatment	ND	5	ND	ND	ND

^A Mass of oil specific to each processing unit.

Level of confidence

Emission factors for this source category are associated with a medium level of confidence for all classes, as they are based on a low data range, but not based on expert judgment, and are derived based on a limited geographical coverage.

The textile industry is one of the longest and most complicated industrial chains in the manufacturing sector. It is a diverse, fragmented group of establishments that produce and/or process textile-related products, such as fiber, yarn, and fabric, for further processing into finished goods. These establishments range from small “back street” operations with few controls to large-scale highly sophisticated industrial operations with comprehensive pollution controls. Because the processes for converting raw fibers into finished products are complex, most textile mills specialize (USEPA 1997b).

Textile production industries are potential sources of PCDD/PCDF due to a number of factors:

• Raw materials may be contaminated with PCDD/PCDF due to treatment with PCDD/PCDF-contaminated pesticides, such as pentachlorophenol;
• Dyes and pigments used on fibers and textiles may be contaminated with PCDD/PCDF, for example, dioxazine dyes produced from chloranil and phthalocyanine-based pigments;
• Finishing processes may include the use of PCDD/PCDF-contaminated chemicals, such as Triclosan, an antimicrobial agent;
• Boilers and heaters may be used for power and heat generation (see Source Group 3);
• Incinerators may be used for disposal of process residues;
• Large volumes of effluent water are released into the environment.
• Formation of PCDD/PCDF during finishing (Križanec et al. 2005).

Details on textile production processes are presented in the BAT&BEP Guidance.

Emission Factors

PCDD/PCDF have been detected in air emissions, wastewater and wastewater treatment sludge from textile mills. However, currently available data are not sufficient to support the derivation of emission factors for these vectors. PCDD/PCDF emission factors for two source classes of products are listed in Table II.7.28. The derivation of these emission factors as well as discussion of existing information on releases to air, water and wastewater treatment sludge are addressed in Annex 50.

Table II.7.28 PCDD/PCDF emission factors for source category 7g Textile Production

7g	Textile Production	Emission Factors (µg TEQ/t textile)
Classification		Air	Water	Land	Product	Residue
1	Low-end technology	ND	ND	ND	100	ND
2	Mid-range, non-BAT technologyA	ND	ND	ND	0.1	ND
3	High-end, BAT technology	NA	NA	NA	NA	NA

^A Textile technology that does not involve either formation of PCDD/PCDF or transfer from another vector.

Level of confidence

Emission factors for this source category are associated with a low level of confidence for all classes, due to scarcity and lack of representativeness of data.

The tannery operation consists of converting the raw skin or hide of an animal into leather for use in the manufacture of a wide range of products. This involves a sequence of complex chemical reactions and mechanical processes. Amongst these, tanning is the fundamental stage, which gives leather its stability and essential character. The tanning industry is a potentially pollution-intensive industry with environmental concerns that include air emissions, wastewater, and solid waste.

PCDD/PCDF have been detected in finished leather goods. Evidence suggests that the sources of PCDD/PCDF are contaminated dyes, such as those derived from chloranil, and contaminated biocides, such as PCP. While leather production processes have not been evaluated for PCDD/PCDF formation or occurrence, the use of PCDD/PCDF-contaminated dyes and biocides chemicals can be expected to result in the occurrence of PCDD/PCDF in process wastewater and sludges from wastewater treatment. Also, new formation of PCDD/PCDF may occur in the leather production chain where process wastewater is treated and where wastewater treatment sludge and other process wastes are incinerated.

Leather production processes are described in greater detail in Annex 51 and in the BAT&BEP Guidelines.

Emission Factors

Emission factors for PCDD/PCDF releases to air, water, land, and residues could not be derived due to lack of information. However, the quantities, methods of treatment, and fate of wastewater, treated wastewater effluents, wastewater treatment sludge, and other solid wastes should be noted to the extent possible since releases to water and residues could be high. If wastewater treatment sludge and/or other wastes are incinerated or otherwise combusted, this should also be noted since release to air and in residues could be high.

Emission factors for release to products are given in Table II.7.29. The derivation of these emission factors is addressed in Annex 51.

Table II.7.29 PCDD/PCDF emission factors for source category 7h Leather Refining

7h	Leather Refining	Emission Factors (µg TEQ/t leather)
Classification		Air	Water	Land	Product	Residue
1	Low-end technology	ND	ND	ND	1,000	ND
2	Mid-range technology	ND	ND	ND	10	ND

Level of confidence

Emission factors for this source category are associated with a low level of confidence for all classes, due to scarcity and lack of representativeness of data.