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Zellstoff Stendal ECF and TCF bleached softwood kraft pulp mill, Germany

Prepared at the request of

Resource Planning and Development Commission

TASMANIA

|Rev |Compiled |Reviewed |Approved |Issued by|Issue date |
|5 |See appendix A |See appendix D |ROM | |ROM | |20-May-06 |

Table of Contents

EXECUTIVE SUMMARY 7

INTRODUCTION 7
CONCLUSIONS 7
SECTION 2 – “REVIEW OF ECF AND TCF BLEACHING PROCESSES” 8
Section 2.4 – “ECF bleaching” 8
Sections 2.5 and 2.6 – “TCFbleaching” and “Current status of BKP mills employing TCF bleaching” 9
Section 2.7 – “Effluent characteristics and treatability” 9
Section 2.8 – “Environmental impact of ECF and TCF bleaching” 11
Section 2.9 – “Process closure of the bleach plant” 12
Section 2.10 – “Bleaching chemical preparation” 12
Section 2.11 – “Pulp quality and marketability” 12
SECTION 3 – “CONVENTIONSRELEVANT TO THE DEBATE ON ECF AND TCF BLEACHING” 14
Section 3.1 – “United Nations Environment Programme - Chemicals” 14
SECTION 4 – “GUIDELINES AND REGULATIONS RELEVANT TO THE DEBATE ON ECF AND TCF BLEACHING” 15
Section 4.5 – “World Bank Group” 15
SECTION 5 – “SPECIFIC ISSUES RAISED IN THE WWF REPORT ON ARAUCO VALDIVIA” 16
Section 5.1 – “Hazard profile of chlorine dioxide” 16Section 5.2 – “Increased concentration of dioxins in the Baltic Sea near ECF mills during 1979-2000” 16
Section 5.3 – “Catalytic oxygen bleaching” 17
Section 5.4 – “Multibio system at SCA Östrand” 17
Section 5.5 – “Tertiary treatment” 18

1 INTRODUCTION 19

1.1 WWF REPORT ON ARAUCO VALDIVIA 19
1.2 TERMINOLOGY 19
1.2.1 Accepted modern technology 19
1.2.2 Best availabletechniques 20
1.2.3 Best practice environmental management 20
1.2.4 Reference tables 20

2 REVIEW OF ECF AND TCF BLEACHING PROCESSES 21

2.1 GENERAL 21
2.1.1 Pulping and oxygen delignification 21
2.1.2 Bleaching 23
2.2 SIGNIFICANT MILESTONES IN BLEACHING 28
2.3 THE SIGNIFICANCE OF DIOXINS IN THE DEVELOPMENT OF MODERN BLEACHING PROCESSES 29
2.3.1 General 292.3.2 Dioxin and furan precursors 30
2.3.3 Toxicity equivalency factors 30
2.4 ECF BLEACHING 32
2.4.1 Sequences 32
2.4.2 Comment regarding Article 5, Annex C of the Stockholm Convention 32
2.4.3 Chlorinated organic compounds 33
2.4.4 Dioxins and furans 34
2.4.5 Market position 35
2.4.6 PCDD/ PCDF in aquatic biota near kraft mills employing ECF bleaching 35
2.5TCF BLEACHING 39
2.5.1 Sequences 39
2.5.2 Chlorinated organic compounds 39
2.5.3 Dioxins and furans 40
2.5.4 Market position 40
2.6 CURRENT STATUS OF BKP MILLS EMPLOYING TCF BLEACHING 42
2.7 EFFLUENT CHARACTERISTICS AND TREATABILITY 45
2.7.1 General comments on effluent treatability 45
2.7.2 ECF effluents 45
2.7.3 TCF effluents 54
2.8 ENVIRONMENTAL IMPACT OFECF AND TCF BLEACHING 58
2.8.1 Conclusions reported in studies carried out in the 1990s and early 2000s 58
2.8.2 Conclusions reported in recent studies 59
2.9 PROCESS CLOSURE OF THE BLEACH PLANT 63
2.9.1 Historical perspective and perceptions 63
2.9.2 Actual results 64
2.9.3 Conclusions 68
2.10 BLEACHING CHEMICAL PREPARATION 69
2.10.1 Chlorine dioxide preparation 692.10.2 Ozone preparation 71
2.10.3 Other bleaching chemicals 71
2.11 PULP QUALITY AND MARKETABILITY 72
2.11.1 Properties of hardwood market pulps produced in different regions 73
2.11.2 Properties of softwood market pulps produced in different regions 75
2.11.3 Mill cases 76
2.11.4 Concluding remarks 79
2.12 ECF AND TCF BLEACHING CHEMICAL SAFETY ISSUES 83...
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