Integrated Pollution Prevention and Control Reference

10,4

MB

Document on the Best Available Techniques for Waste

638

stron

5643

ID

JRC-IPTS Instituto de Prospectiva Tecnológica (IPTS)

2006

rok

EXECUTIVE SUMMARYI

PREFACEXI

SCOPE XXXIII

1 GENERAL INFORMATION ON WASTE INCINERATION . 1

1.1 Purpose of incineration and basic theory . 1

1.2 Overview of waste incineration in Europe . 2

1.3 Plant sizes 5

1.4 Overview of legislation 6

1.5 Waste composition and process design 6

1.6 Key environmental issues 9

1.6.1 Process emissions to air and water 9

1.6.2 Installation residues production 10

1.6.3 Process noise and vibration. 11

1.6.4 Energy production and consumption 12

1.6.5 Consumption of raw materials and energy by the installation 13

1.7 Economic information 13

2 APPLIED TECHNIQUES 19

2.1 Overview and introduction. 19

2.2 Pretreatment, storage and handling techniques 20

2.2.1 Municipal solid wastes (MSW) 21

2.2.1.1 Collection and pretreatment outside the MSW incineration plant. 21

2.2.1.2 Municipal solid waste pretreatment within the incineration plant. 22

2.2.1.3 Waste delivery and storage . 22

2.2.1.3.1 Waste control . 22

2.2.1.3.2 Bunker 22

2.2.2 Hazardous wastes 23

2.2.2.1 Brief description of the sector . 23

2.2.2.2 Waste acceptance 24

2.2.2.3 Storage 25

2.2.2.3.1 Storage of solid hazardous waste . 26

2.2.2.3.2 Storage of pumpable hazardous waste . 26

2.2.2.3.3 Storage for containers and tank containers. 27

2.2.2.4 Feeding and pretreatment 27

2.2.3 Sewage sludge 28

2.2.3.1 Composition of sewage sludge 28

2.2.3.2 Pretreatment of sewage sludge 29

2.2.3.2.1 Physical dewatering . 29

2.2.3.2.2 Drying 30

2.2.3.2.3 Sludge digestion. 31

2.2.4 Clinical waste 31

2.2.4.1 Nature and composition of clinical wastes 31

2.2.4.2 Handling, pretreatment and storage of clinical waste 32

2.3 The thermal treatment stage . 32

2.3.1 Grate incinerators 35

2.3.1.1 Waste feeder 36

2.3.1.2 Incineration grate 36

2.3.1.2.1 Rocking grates 37

2.3.1.2.2 Reciprocating grates. 37

2.3.1.2.3 Travelling grates 38

2.3.1.2.4 Roller grates . 38

2.3.1.2.5 Cooled grates . 38

2.3.1.3 Bottom ash discharger. 38

2.3.1.4 Incineration chamber and boiler 39

2.3.1.5 Incineration air feeding . 41

2.3.1.6 Auxiliary burner 42

2.3.1.7 Incineration temperature, residence time, minimum oxygen content 42

2.3.1.8 Sewage sludge incineration in MSWI plants .42

2.3.1.9 Addition of clinical waste to a municipal waste incinerator 43

2.3.2 Rotary kilns .44

2.3.2.1 Kilns and post combustion chambers for hazardous waste incineration45

2.3.2.2 Drum kiln with post-combustion chamber for hazardous waste incineration45

2.3.3 Fluidised beds47

2.3.3.1 Stationary (or bubbling) fluidised bed incineration .49

2.3.3.2 Circulating fluidised bed (CFB) for sewage sludge.51

2.3.3.3 Spreader-stoker furnace .51

2.3.3.4 Rotating fluidised bed52

2.3.4 Pyrolysis and gasification systems 52

2.3.4.1 Introduction to gasification and pyrolysis52

2.3.4.2 Gasification53

2.3.4.2.1 Examples of gasification processes 55

2.3.4.3 Pyrolysis 56

2.3.4.3.1 Example of a pyrolysis process 58

2.3.4.3.2 Example of pyrolysis in combination with a power plant 59

2.3.4.4 Combination processes 61

2.3.4.4.1 Pyrolysis – incineration 61

2.3.4.4.2 Pyrolysis – gasification.64

2.3.4.4.3 Gasification – combustion 66

2.3.5 Other techniques67

2.3.5.1 Stepped and static hearth furnaces.67

2.3.5.2 Multiple hearth furnaces 67

2.3.5.3 Multiple hearth fluidised bed furnace 70

2.3.5.4 Modular systems70

2.3.5.5 Incineration chambers for liquid and gaseous wastes 71

2.3.5.6 Cycloid incineration chamber for sewage sludge 72

2.3.5.7 Example of process for the incineration of liquid and gaseous chlorinated wastes with HCl

recovery72

2.3.5.8 Example of a process for the incineration of highly chlorinated liquid wastes with chlorine

recycling 74

2.3.5.9 Waste water incineration .75

2.3.5.10 Plasma technologies.77

2.3.5.11 Various techniques for sewage sludge incineration .79

2.4 The energy recovery stage 81

2.4.1 Introduction and general principles .81

2.4.2 External factors affecting energy efficiency82

2.4.2.1 Waste type and nature82

2.4.2.2 Influence of plant location on energy recovery .84

2.4.2.3 Factors taken into account when selecting the design of the energy cycle 86

2.4.3 Energy efficiency of waste incinerators 87

2.4.3.1 Energy inputs to waste incinerators .87

2.4.3.2 Energy outputs from waste incinerators 88

2.4.4 Applied techniques for improving energy recovery 88

2.4.4.1 Waste feed pretreatment 88

2.4.4.2 Boilers and heat transfer 89

2.4.4.2.1 Corrosion in boilers 91

2.4.4.3 Combustion air preheating.93

2.4.4.4 Water cooled grates .93

2.4.4.5 Flue-gas condensation .93

2.4.4.6 Heat pumps 95

2.4.4.6.1 Compressor driven heat pumps 95

2.4.4.6.2 Absorption heat pumps.96

2.4.4.6.3 Open heat pumps 96

2.4.4.6.4 Example data of different heat pumps 96

2.4.4.7 Flue-gas re-circulation .97

2.4.4.8 Reheating of flue-gases to the operation temperature FGT devices 97

2.4.4.9 Plume visibility reduction97

2.4.4.10 Steam-water cycle improvements: effect on efficiency and other aspects.97

2.4.5 Steam generators and quench cooling for hazardous waste incinerators.98

2.4.6 Examples of energy recovery from fluidised bed incinerators 99

2.5 Applied flue-gas treatment and control systems .100

2.5.1 Summary of the application of FGT techniques . 100

2.5.2 Overview of overall combined FGT system options 102

2.5.3 Techniques for reducing particulate emissions . 102

2.5.3.1 Electrostatic precipitators 103

2.5.3.2 Wet electrostatic precipitators. 103

2.5.3.3 Condensation electrostatic precipitators 104

2.5.3.4 Ionisation wet scrubbers 105

2.5.3.5 Fabric filters 105

2.5.3.6 Cyclones and multi-cyclones. 106

2.5.4 Techniques for the reduction of acid gases (e.g. HCl, HF and SOX emissions) 107

2.5.4.1 Removal of sulphur dioxide and halogens 107

2.5.4.2 Direct desulphurisation . 110

2.5.5 Techniques for the reduction of emissions of oxides of nitrogen . 111

2.5.5.1 Primary techniques for NOX reduction 111

2.5.5.1.1 Air supply, gas mixing and temperature control 111

2.5.5.1.2 Flue-Gas Recirculation (FGR) . 112

2.5.5.1.3 Oxygen injection 112

2.5.5.1.4 Staged combustion . 112

2.5.5.1.5 Natural gas injection (re-burn) . 112

2.5.5.1.6 Injection of water into furnace/flame . 112

2.5.5.2 Secondary techniques for NOX reduction 112

2.5.5.2.1 Selective Non-Catalytic Reduction (SNCR) process . 113

2.5.5.2.2 Selective Catalytic Reduction (SCR) process 115

2.5.6 Techniques for the reduction of mercury emissions . 116

2.5.6.1 Primary techniques 116

2.5.6.2 Secondary techniques 116

2.5.7 Techniques for the reduction of other emissions of heavy metals 117