Reference Document on Best Available Techniques in the

5,32
MB Ferrous Metals Processing Industry (adopted Dec 2001)

538
stron

1103
ID JRC-IPTS Instituto de Prospectiva Tecnológica (IPTS)

2002
rok

Executive Summary. i

Preface xxi

A.1 General Information on Hot and Cold Forming 1

A.1.1 Hot Rolled Flat Products2

A.1.2 Hot Rolled Long Products3

A.1.3 Tubes.4

A.1.4 Cold Rolled Flat Products 5

A.1.5 Cold Drawn Long Products/ Bright Steel Bars 8

A.1.6 Wire 8

A.2 Applied Processes and Techniques in Hot and Cold Forming.11

A.2.1 Hot Rolling Mills .11

A.2.1.1 Process Overview.11

A.2.1.1.1 Blooming/Slabbing Mills.13

A.2.1.1.2 Hot Strip Mills .13

A.2.1.1.3 Plate Mills16

A.2.1.1.4 Bar and Rod Mills17

A.2.1.1.5 Structural/Section Mills .19

A.2.1.1.6 Tube Mill .22

A.2.1.2 Surface Rectification and Conditioning of Input25

A.2.1.3 Reheating- and Heat Treatment Furnaces 26

A.2.1.3.1 Batch Furnaces.26

A.2.1.3.2 Continuous Furnaces27

A.2.1.4 Descaling.29

A.2.1.5 Edging 30

A.2.1.6 Roughing 30

A.2.1.7 Strip Rolling/Finishing Train .30

A.2.1.8 Rod Rolling/Finishing Train 30

A.2.1.9 Plate Rolling.31

A.2.1.10 Transport of Roll Stock between Rolling Stands .31

A.2.1.11 Cooling Lines .31

A.2.1.12 Sheet and Plate Production.32

A.2.1.13 Plate Heat Treatment 32

A.2.1.14 Roll Shop33

A.2.1.15 Water Circuits / Water Management in Hot Rolling Mills.33

A.2.1.16 Waste and By-product Management in Hot Rolling Mills .36

A.2.2 Cold Rolling Mills .38

A.2.2.1 Process Overview.38

A.2.2.2 Pickling of Low Alloy and Alloy HR Steel40

A.2.2.3 Annealing (I) and Pickling (I) of High Alloy HR Steel41

A.2.2.4 Cold Rolling of the Pickled Hot Rolled Strip.43

A.2.2.4.1 Low Alloy and Alloy Steel 43

A.2.2.4.2 High Alloy Steel 44

A.2.2.5 Annealing of Low Alloy and Alloy Steel.45

A.2.2.5.1 Batch Annealing.45

A.2.2.5.2 Continuous Annealing .46

A.2.2.6 Annealing (II) and Pickling (II) of High Alloy Steel .47

A.2.2.7 Tempering of Cold Rolled Strip .48

A.2.2.7.1 Low Alloy and Alloy Steel 48

A.2.2.7.2 High Alloy Steel 48

A.2.2.8 Finishing49

A.2.2.9 Roll Shop49

A.2.2.10 Water and Process Baths Management in Cold Rolling Mills .50

A.2.2.10.1 Emulsion System .50

A.2.2.10.2 Degreasing Solution System51

A.2.2.10.3 Cooling Water Systems51

A.2.2.10.4 Waste Water Treatment .53

A.2.2.11 Waste and By-product Management in Cold Rolling Mills .53

A.2.3 WIRE PLANTS .54

A.2.3.1 Wire Drawing Process Overview. 54

A.2.3.2 Wire Rod Preparation 55

A.2.3.2.1 Mechanical Descaling of Wire Rod. 56

A.2.3.2.2 Chemical Descaling (Pickling) of Wire Rod. 56

A.2.3.2.3 Application of Soap (Lubricant) Carrier . 56

A.2.3.3 Drawing . 57

A.2.3.3.1 Dry Drawing of Wire 57

A.2.3.4 Heat Treatment of Wire . 57

A.2.3.4.1 Batch Annealing of Low Carbon Steel Wire. 57

A.2.3.4.2 Continuous (In-Line) Annealing of Low Carbon Steel Wire 58

A.2.3.4.3 Continuous (In-Line) Annealing of Stainless Steel Wire 58

A.2.3.4.4 Patenting 58

A.2.3.4.5 Oil Hardening and Tempering (Oil Tempering) 59

A.2.3.4.6 Stress-relieving 59

A.2.3.5 In-line Pickling 60

A.3 Present Consumption and Emission Levels for Hot and Cold Forming 61

A.3.1 Hot Rolling Mills. 61

A.3.1.1 Mass Stream Overview 61

A.3.1.2 Surface Rectification and Conditioning of Input . 62

A.3.1.3 Reheating and Heat Treatment Furnaces . 63

A.3.1.4 Descaling . 65

A.3.1.5 Hot Rolling 67

A.3.1.6 Roll Shop . 67

A.3.1.7 Oil, Grease and Hydraulic Oil Flow 67

A.3.1.8 Hot Rolling Mill Waste Water Treatment Plant 69

A.3.1.9 Waste and Recycling . 70

A.3.1.10 Noise Issues in Hot Rolling . 71

A.3.1.11 Commissioning and Decommissioning . 71

A.3.2 Cold Rolling Mills. 73

A.3.2.1 Mass Stream Overview 73

A.3.2.2 Pickling of Low Alloy, Alloy and High Alloy Steel 74

A.3.2.2.1 Hydrochloric Acid Pickling Line and Regeneration Plant 75

A.3.2.2.2 Sulphuric Acid Pickling Line and Regeneration Plant 77

A.3.2.2.3 Mixed (HNO3-HF) Acid Pickling Line and Acid Recovery 79

A.3.2.3 Cold Rolling. 80

A.3.2.3.1 Low Alloy . 80

A.3.2.3.2 High Alloy/Reversing Mill 82

A.3.2.4 Annealing of Low Alloy and Alloy Steel 83

A.3.2.4.1 Batch Annealing 83

A.3.2.4.2 Continuous Annealing. 84

A.3.2.5 Annealing and Pickling of High Alloy Steel 85

A.3.2.6 Tempering (Low alloy/High Alloy). 87

A.3.2.7 Finishing (Cutting, Inspection, Packing) . 87

A.3.2.8 Roll Shop . 88

A.3.2.9 Hydraulic Fluids and Lubricants Management 88

A.3.2.10 Cold Rolling Mill Waste Water Treatment Plant. 89

A.3.2.11 Waste and Recycling . 91

A.3.2.12 Noise Issues in Cold Rolling 91

A.3.3 Wire Plant. 93

A.3.3.1 Mass Stream Overview 93

A.3.3.2 Wire Rod Preparation 94

A.3.3.2.1 Mechanical Descaling of Wire Rod. 94

A.3.3.2.2 Chemical Descaling/Pickling of Wire Rod . 94

A.3.3.2.3 Application of Soap Carrier. 95

A.3.3.3 Drawing of Wire 96

A.3.3.3.1 Dry Drawing 96

A.3.3.3.2 Wet Drawing . 97

A.3.3.4 Heat Treatment of Wire . 99

A.3.3.4.1 Batch Annealing/Bell and Pot Furnaces 99

A.3.3.4.2 Continuous Annealing/Molten Lead Bath. 99

A.3.3.4.3 Patenting 100

A.3.3.4.4 Oil Hardening & Tempering . 101

A.3.3.4.5 Annealing of Stainless Steel Wire .102

A.3.3.4.6 Stress Relieving .102

A.3.3.5 Noise Issues in a Wire Plant.102

A.4 Techniques to Consider in the Determination of BAT for Hot and Cold Forming105

A.4.1 HOT ROLLING MILL 105

A.4.1.1 Storage and Handling of Raw Materials and Auxiliaries .105

A.4.1.2 Surface Rectification and Conditioning of Input105

A.4.1.2.1 Enclosed Scarfing Operation with Wastegas Cleaning105

A.4.1.2.2 Enclosed Grinding Operation with Waste Gas Cleaning .107

A.4.1.2.3 CAQC - Computer Aided Quality Control 109

A.4.1.2.4 Rolling of Wedge-type Slabs .110

A.4.1.2.5 Slab Slitting110

A.4.1.3 Reheating and Heat Treatment Furnaces111

A.4.1.3.1 General Measures for Energy Efficiency and Low Emission Operation .111

A.4.1.3.2 Furnace Automation / Furnace Control113

A.4.1.3.3 Optimised Furnace Door Design114

A.4.1.3.4 Regenerative Burner System115

A.4.1.3.5 Recuperator and Recuperative Burners117

A.4.1.3.6 Oxy-fuel Technology .117

A.4.1.3.7 Low-NOx Burners .118

A.4.1.3.8 Selective Catalytic Reduction (SCR) .119

A.4.1.3.9 Selective Non-Catalytic Reduction (SNCR) 121

A.4.1.3.10 External Flue Gas Recirculation (FGR).123

A.4.1.3.11 Waste Heat Boiler123

A.4.1.3.12 Optimised Skid Design to Reduce Skid Marks125

A.4.1.3.13 Reduction of Energy Loss through Stock Transportation Device126