Contents
Foreword: Why this booklet?
1. Primary treatment
1.1 Objectives
1.2 Screening
1.2.1 Bar screening, removal of larger solids
1.2.2 Removal of grit and floating matter
1.2.3 Self-cleaning screens
1.3 Pumping/lifting
1.3.1 Submersible pump
1.3.2 Screw (Archimedes) pump
1.4 Fine screening
1.5 Equalization – homogenization – sulphide oxidation
1.6 Chemical treatment (coagulation, flocculation)
1.7 Settling – primary sedimentation
1.8 Sludge dewatering
1.8.1 Sludge thickener
1.8.2 Belt-filter press
1.8.3 Centrifuge
1.8.4 Sludge-drying beds
2. Biological (secondary) treatment
2.1 Objective and basic principles
2.2 Main operational parameters
2.3 Other operational parameters
2.4 Aeration devices
2.5 Aeration basins, oxidation ditch
2.6 Secondary sedimentators
2.7 Anaerobic biological treatment
3. Advanced (tertiary) treatment
4. Sludge handling
4.1 Mechanical sludge dewatering
4.2 Utilization and disposal
5. The issue of bad odour
6. Monitoring, costs, OSH, management
7. Conclusions