This book deals with natural treatment systems and the challenges the water industry faces in dealing with sustainability and the realisation of reaching Net Zero by 2030. Surface waters are all under threat, with freshwater ecosystems now facing unprecedented levels of contamination, even after a century of ever stricter legislation and regulation. The increase in population and especially in urbanization without sufficient planning and investment to ensure adequate wastewater collection and treatment coupled with the need to reduce greenhouse gas emissions associated with wastewater treatment is leading to a crisis in wastewater treatment in many countries. Natural treatment systems which use plants and soil micro-organisms are very much nature-based solutions and wherever applicable might offer sustainable and low emissions options for a range of wastewater problems protecting surface waters as well as creating new habitats to support and enhance wildlife diversity. In terms of circularity, natural treatment systems have the potential to produce a staggering array of useful and valuable by-products, including high-value compounds for the pharmaceutical industry.
Author(s): Nicholas F. Gray
Publisher: World Scientific Publishing
Year: 2021
Language: English
Pages: 523
City: London
Contents
Preface
Acknowledgments
Part I Introduction to Sustainable Natural Wastewater Treatment
1 Sustainability and Water
1.1 Defining Sustainability and Sustainable Development
1.2 Sustainability and the Water Industry
1.2.1 The hydrological cycle
1.2.2 The global water crisis
1.2.3 Water footprints
1.3 Sustainability in Wastewater Treatment
References
2 The Circular Economy
2.1 What is the Circular Economy?
2.2 The Circular Economy and the Water Industry
2.2.1 Introduction
2.2.2 The water pathway
2.2.3 The materials pathway
2.2.4 The energy pathway
References
3 Global Warming and Climate Change
3.1 Introduction
3.2 GHG Emissions and the Water Industry
References
4 Natural Treatment Systems
4.1 The Concept of Natural Treatment
4.2 Selection of Processes
References
Part II Land Treatment
5 The Purification Process
5.1 Introduction to Land Treatment
5.2 The Process of Treatment
5.3 Evapotranspiration
5.4 Salinity and Sodicity
5.5 Contaminant Problems
5.6 Pathogen Removal
References
6 Subsurface Wastewater Infiltration Systems
6.1 Introduction
6.2 Design of the SWIS
6.3 Biomat Formation and Treatment
References
7 Slow-rate Irrigation Processes
7.1 Introduction to Slow-rate Land Treatment
7.2 Process Design
7.3 Crop Irrigation
7.3.1 Performance
7.3.2 Salinity intolerance
7.4 Forestry
References
8 Rapid Infiltration Processes
8.1 High-rate Irrigation
8.2 Irrigation–percolation
8.2.1 Rapid infiltration basins (RIBs)
8.2.2 Soil aquifer treatment (SAT) systems
8.2.3 Problems with RIB and SAT processes
References
9 Overland Flow
9.1 Introduction
9.2 The Treatment Process
9.3 Operational Management and Performance
References
Part III Constructed Wetland Systems
10 The Use of Microalgae and Macrophytes in Wastewater Treatment
10.1 Introduction
10.2 Microalgae
10.3 Submerged Macrophytes
10.4 Floating Macrophytes
10.4.1 Introduction
10.4.2 Water hyacinth
10.4.3 Duckweeds and water ferns
References
11 High-rate Algal Ponds and Photobioreactors
11.1 Design and Operational Basis of HRAPs and PBRs
11.2 The Role of Microalgae in Wastewater Treatment
11.2.1 Chlorophytes (green algae)
11.2.2 Cyanobacteria (blue-green algae)
11.2.3 Microalgal aggregates
11.3 Algal Productivity, Harvesting Methods and Uses of the Algal Crop
11.3.1 Algae as a source of protein and other nutrients
11.3.2 Algae as a biofuel
11.3.3 Harvesting algae
11.4 Microalgae and Sustainability
References
12 Wetlands
12.1 Introduction
12.2 Natural Wetlands
12.3 Removal Processes
12.4 Natural Wetlands for Wastewater Treatment
12.5 Conclusions
References
13 Constructed Wetlands Incorporating Emergent Vegetation
13.1 Introduction
13.2 Free Water Surface Treatment Wetlands
13.3 Subsurface Flow Treatment Wetlands
13.3.1 Design of horizontal flow reed bed treatment systems
13.3.2 Design of vertical flow reed bed treatment systems
13.3.3 Design of hybrid reed bed treatment systems
13.4 Pathogen Removal
References
Part IV Waste Stabilization Ponds
14 Introduction to Waste Stabilization Ponds and Lagoons
14.1 Development of Waste Stabilization Ponds (WSPs)
14.2 Case Studies
14.2.1 Medium to large scale WSP treatment system
14.2.2 Small scale WSP treatment system
14.3 Design
References
15 Anaerobic Lagoons
15.1 The Process
15.2 Microbiology
15.3 Application
15.4 Design of Anaerobic Lagoons
15.5 Gas Emissions from Lagoons
15.5.1 Methane and carbon dioxide
15.5.2 Ammonia
15.5.3 Odors and hydrogen sulfide
15.5.4 Denitrification
15.6 Covered Lagoons for Biogas Collection
References
16 Oxidation Ponds
16.1 Introduction to Oxidation Ponds
16.2 Facultative Ponds
16.2.1 Basis of operation
16.2.2 Ecology
16.2.3 Factors affecting performance
16.2.4 Design
16.2.5 Application
16.3 Maturation Ponds
16.4 Fishponds
16.5 River Purification Lakes
16.6 Pathogen Removal in Waste Stabilization Ponds
16.7 Contaminant Removal in Waste Stabilization Ponds
References
17 Partially and Completely Mixed Aerated Ponds
17.1 Introduction
17.2 Partially Mixed Aerated Ponds
17.3 Completely Mixed Aerated Ponds
References
Part V The Future
18 Sustainable Wastewater Treatment Systems
18.1 Assessing Sustainable Options
18.2 Emerging Technologies
18.3 The Role of Natural Treatment in a Sustainable Water Industry
References
Index
