|
Acknowledgements
|
7
|
|
List of figures
|
15
|
|
List of tables and boxes
|
16
|
|
Glossary
|
17
|
|
Abbreviations
|
20
|
|
1 Introduction
|
21
|
|
1.1 Background
|
21
|
|
1.2 Objectives
|
21
|
|
1.3 Scope and definitions
|
21
|
|
1.4 Structure and use of report
|
23
|
|
2 Wastewater and its treatment
|
25
|
|
2.1 Waste water constituents and transfer
|
25
|
|
2.2 Basic assessments
|
26
|
|
2.3 Assessments based on surveys
|
29
|
|
2.4 Effluent quality requirements
|
30
|
|
2.5 Principal methods of wastewater treatment
|
34
|
|
2.6 Types of treatment system
|
36
|
|
2.7 System selection
|
38
|
|
3 International review of package plant practice
|
41
|
|
3.1 US perspective
|
41
|
|
3.2 European standards
|
42
|
|
3.3 UK situation
|
44
|
|
4 Assessing flow and loads
|
47
|
|
4.1 Diurnal flow and load variations
|
47
|
|
4.2 Flow and load balancing
|
50
|
|
4.3 Annual flow variations
|
54
|
|
4.4 Designing for annual flow variations
|
54
|
|
5 Package plant design and costs
|
55
|
|
5.1 Influent requirements
|
55
|
|
5.2 Flowsheets
|
56
|
|
5.3 Loading rates
|
58
|
|
5.4 Package plant treatment capacities
|
62
|
|
5.5 Sludge production
|
66
|
|
5.6 Costs
|
67
|
|
6 Plant material and construction
|
71
|
|
6.1 General
|
71
|
|
6.2 Biological filters
|
72
|
|
6.3 Primary sedimentation and secondary settling tanks (primary and humus)
|
73
|
|
6.4 Rotating biological contractors
|
74
|
|
6.5 Submerged and biological aerated filters
|
74
|
|
6.6 Continuous activated sludge plants
|
75
|
|
6.7 Sequence batch reactors
|
76
|
|
7 Environmental aspects, site selection and plant installation
|
77
|
|
7.1 Environmental aspects
|
77
|
|
7.2 Site selection and specification
|
78
|
|
7.3 Plant installation, commissioning and ownership
|
79
|
|
8 Safety, operation and maintenance
|
53
|
|
8.1 Safety
|
53
|
|
8.2 Package plant operation
|
85
|
|
8.3 Routine monitoring and cleaning
|
86
|
|
8.4 Servicing and maintenance
|
86
|
|
9 Framework for package plant selection
|
89
|
|
9.1 Selection procedure
|
89
|
|
9.2 Stage 1 - consult planning authority and environmental regulator
|
90
|
|
9.3 Stage 2 - determine performance requirements
|
90
|
|
9.4 Stage 3 - assess pollution load
|
91
|
|
9.5 Stage 4 - select potential process options
|
92
|
|
9.6 Stage 5 - identify most cost-effective options
|
96
|
|
References
|
99
|
|
Appendices
|
103
|
|
A - survey of UK package-plant variants
|
103
|
|
B - plant performance data
|
112
|
|
C - process selection checklist
|
114
|
