Sustainable Water Treatment E-Book
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- Herausgeber: John Wiley & Sons
- Kategorie: Wissenschaft und neue Technologien
- Sprache: Englisch
SUSTAINABLE WATER TREATMENT: ADVANCES AND INTERVENTIONS This outstanding new volume is a compendium of reference material which will cover most of the relevant and state-of-art approaches in the field of water treatment, focusing on technological advances for water treatment in four categories: advanced oxidation technologies, nanoparticles for water treatment, membrane separations, and other emerging technologies or processes. Apart from this perspective, fundamental discussions on a wide variety of pollutants have also been included, such as acidic wastewater treatment, metallurgical wastewater, textile wastewater as well as groundwater. The editors have not only covered a wide range of water treatment techniques, but also focus on their applications, offering a holistic perspective on water treatment in general. Covering all of the latest advances, innovations, and developments in practical applications for sustainable water treatment, this volume represents the most comprehensive, up-to-date coverage of the issues of the day and state of the art. Whether for the veteran engineer or scientist or a student, this volume is a must-have for any library. Sustainable Water Treatment: Advances and Interventions covers: * Provides an insight into various sectors of water and wastewater treatment technologies, introducing key technical topics * Is a comprehensive guide to technological interventions for water and wastewater treatment * Is also a reference book for any elective course on water treatment for engineers, scientists, and students, at both the undergraduate and graduate levels * Presents the most current and up-to-date advances in sustainable water treatment * Covers key technical topics and gives readers a comprehensive understanding of the latest research findings * Includes perspectives on future trends and challenges
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Table of Contents
Cover
Title Page
Copyright
Introduction to Water Treatment: A Historical Perspective on Technological Development and Future Landscape
Introduction
Acknowledgement
References
Section I: ADVANCED OXIDATION PROCESSES
1 Advanced Oxidation Processes: Fundamental, Technologies, Applications and Recent Advances
1.1 Introduction
1.2 Background and Global Trend of Advanced Oxidation Process
1.3 Advanced Oxidation Systems
1.4 Comparison and Challenges of AOP Technologies
1.5 Conclusion and Perspective
References
2 A Historical Approach for Integration of Cavitation Technology with Conventional Wastewater Treatment Processes
2.1 Introduction to Cavitation for Wastewater Treatment
2.2 Importance of Integrating Water Treatment Technology in Present Scenario
2.3 Integration Ultrasound Cavitation (UC) with Conventional Treatment Techniques
2.4 Integration of Hydrodynamic Cavitation (HC) with Conventional Treatment Techniques
2.5 Scale-Up Issues with Ultrasound Cavitation Process
2.6 Conclusion and Future Perspectives: Hydrodynamic Cavitation as a Future Technology
Acknowledgements
References
3 Hydrodynamic Cavitation: Route to Greener Technology for Wastewater Treatment
3.1 Introduction
3.2 Cavitation: General Perspective
3.3 Hydrodynamic Cavitation Reactors
3.4 Effect of Operating Parameters of HC
3.5 Toxicity Assessment
3.6 Techno-Economic Feasibility
3.7 Applications
3.8 Conclusions and Thoughts About the Future
3.9 Acknowledgement
3.10 Disclosure
Nomenclature
References
4 Recent Trends in Ozonation Technology: Theory and Application
4.1 Introduction
4.2 Fundamentals of Mass Transfer
4.3 Mass Transfer of Ozone in Water
4.4 Factors Affecting Hydrodynamics and Mass Transfer in Bubble Column Reactor
4.5 Application
4.6 Conclusion and Thoughts About the Future
Acknowledgement
Nomenclature
References
Section II: NANOPARTICLE-BASED TREATMENT
5 Nanoparticles and Nanocomposite Materials for Water Treatment: Application in Fixed Bed Column Filter
5.1 Introduction
5.2 Target Contaminants: Performance of Nanoparticles and Nanocomposite Materials
5.3 Application of Nanoparticles and Nanocomposite Materials in Fixed Bed Column Filter for Water Treatment
References
6 Nanomaterials for Wastewater Treatment: Potential and Barriers in Industrialization
6.1 Introduction
6.2 Nanomaterials in Wastewater Treatment
6.3 Smart Nanomaterials: Molecularly Imprinted Polymers (MIP)
6.4 Cheap Alternative Nanomaterials
6.5 Toxicity Associated with Nanotechnology in Wastewater Treatment
6.6 Barriers in Industrialization
6.7 Future Aspect and Conclusions
References
Section III: MEMBRANE-BASED TREATMENT
7 Microbial Fuel Cell Technology for Wastewater Treatment
7.1 Introduction
7.2 Microbial Fuel Cell
7.3 Recent Development in MFC Component
7.4 MFC for Wastewater Treatment
7.5 Different Ways for Increasing the Throughput of MFC
7.6 Different Case Studies Indicating Commercial Use of MFC
7.7 Other Applications of MFC
7.8 Conclusions and Recommendations (Future Work)
References
8 Ceramic Membranes in Water Treatment: Potential and Challenges for Technology Development
8.1 Introduction
8.2 Treatment of Contaminated Groundwater and Drinking Water
8.3 Classification of Filtration Based on Configuration
8.4 Pilot-Scale Studies
8.5 Challenges of Ceramic Membranes
8.6 Conclusion and Future Scope of Ceramic Membranes
References
9 Membrane Distillation for Acidic Wastewater Treatment
9.1 Introduction
9.2 Membrane Distillation and Its Configurations
9.3 Sources of Acidic Effluent
9.4 Applications of MD for Acidic Wastewater Treatment
9.5 Hybrid MD Process
9.6 Implications
References
10 Demonstration of Long-Term Assessment on Performance of VMD for Textile Wastewater Treatment
10.1 Introduction
10.2 Transport Mechanism
10.3 Impact of Process Variables on Permeate Flux
10.4 Long-Term Performance Analysis of VMD
10.5 Scale Formation in Long-Term Assessment
Conclusion
Nomenclature
Greek Symbols
References
Section IV: EMERGING TECHNOLOGIES & PROCESSES
11 Application of Zero Valent Iron to Removal Chromium and Other Heavy Metals in Metallurgical Wastewater
11.1 Introduction
11.2 Materials and Methods
11.3 Results and Discussion
11.4 Conclusion
Acknowledgements
References
12 Removal of Arsenic and Fluoride from Water Using Novel Technologies
12.1 Background Study of Arsenic
12.2 Background Study of Fluoride
12.3 Technologies Used for Arsenic Removal from Contaminated Groundwater
12.4 Technologies for Fluoride Removal from Contaminated Groundwater
12.5 Membrane Technology Used for Arsenic and Fluoride Mitigations
References
13 A Zero Liquid Discharge Strategy with MSF Coupled with Crystallizer
13.1 Introduction
13.2 Minimum Energy Required for Desalination Process
13.3 Methodology and Simulation
13.4 Results and Discussion
13.5 Conclusion
13.6 Acknowledgment
References
14 A Critical Review on Prospects and Challenges in “Conceptualization to Technology Transfer” for Nutrient Recovery from Municipal Wastewater
14.1 Introduction
14.2 Chemical Processes for Resources Recovery
14.3 Biological Processes for Resources Recovery
14.4 Membrane-Based Hybrid Technologies for Nutrients, Energy, and Water Recovery
14.5 Conclusion
Acknowledgements
Disclosure
References
15 Sustainable Desalination: Future Scope in Indian Subcontinent
15.1 Introduction
15.2 Water Supply and Demand in India
15.3 Current Status of Desalination in India
15.4 Commercially Available Technologies
15.5 Possible Technological Intervention
15.6 Challenges and Implementation Strategies for Sustainable Use of Desalination Technologies
References
16 Desalination: Thermodynamic Modeling and Energetics
16.1 Introduction
16.2 Thermodynamics Modeling of Desalination
16.3 Modeling of Major Thermal Desalination Techniques
16.4 Advantage of RO Above Other Mentioned Technologies
16.5 Exergy Analysis of Reverse Osmosis
16.6 Conclusion
Nomenclature
References
Index
Also of Interest
End User License Agreement
List of Illustrations
Chapter 1
Figure 1.1 (a) The annual trend in the number of advanced oxidation process publ...
Figure 1.2 Classification of AOP systems.
Chapter 2
Figure 2.1 Comparison of hydrogel & hydrogel with ultrasound on adsorption of CV...
Figure 2.2 In-house fabricated experimental setup (hybrid treatment system) [44]...
Figure 2.3 Percentage reduction in TOC as a function of time at different optimi...
Chapter 3
Figure 3.1 Phase diagram of water.
Figure 3.2 Working principle of cavitating device (Orifice plate).
Figure 3.3 Mechanism of free radical development within a cavity [Reproduced wit...
Figure 3.4 Typical pressure axis profile [Reproduced with permission from A.B. P...
Figure 3.5 Different cavitation regimes [Reproduced with permission from A. Ferr...
Figure 3.6 HC-based technologies in Water-Energy-Food-Health Nexus.
Chapter 4
Figure 4.1 Concentration profile of the gas phase and liquid phase on the two si...
Figure 4.2 Schematic diagram of reaction of ozone molecule with water.
Figure 4.3 Bubble formation in a typical gas-liquid contactor.
Figure 4.4 Schematic representation of reaction mechanism of ozone molecules wit...
Figure 4.5 Different applications based on ozone treatment for water-food-health...
Figure 4.6 Comparison between the articles on treatment of effluents derived fro...
Chapter 5
Figure 5.1 Schematic representation of sources and pathways of different types o...
Figure 5.2 Conceptual diagram representing different types of nanoparticles and ...
Figure 5.3 Conceptual diagram of the column showing transport and sorption of so...
Figure 5.4 A diagram presenting the contaminant concentration over volume of wat...
Chapter 6
Figure 6.1 Schematic representation showing different types of nanomaterials use...
Chapter 7
Figure 7.1 Comparison of life cycle emissions of various resources [2].
Figure 7.2 Working principle of microbial fuel cell.
Figure 7.3 Schematic diagram of single chamber MFC. (Figure reproduced with perm...
Figure 7.4 Schematic diagram of two-chambered MFC [16].
Figure 7.5 Schematic diagram of stack MFC. (Figure reproduced with permission fr...
Figure 7.6 Schematic diagram of upflow MFC. (Figure reproduced with permission f...
Figure 7.7 Advantages of MFC in wastewater treatment.
Figure 7.8 Challenges in the up-scaling of MFCs in wastewater treatment.
Figure 7.9 Application of MFCs.
Chapter 8
Figure 8.1 Comparative analysis of colour removal from textile wastewater by cer...
Figure 8.2 Comparative analysis of colour and COD removal from textile wastewate...
Figure 8.3 (a) Single-channel and (b) 19-channel MF supports used for tannery wa...
Figure 8.4 Surface microstructure of clay-alumina based ceramic microfiltration ...
Figure 8.5 FESEM of porous ceramic support (a) without and (b) with tannery slud...
Figure 8.6 Surface microstructure of γ-alumina coated ceramic ultrafiltration me...
Figure 8.7 Ceramic membrane based arsenic removal plant developed by CSIR-CGCRI ...
Figure 8.8 Comparative analysis of fluoride removal from contaminated water by c...
Figure 8.9 Schematic of MBR (a) side-stream mode (b) submerged mode.
Figure 8.10 FESEM of (a) Al
2
O
3
MF support and (b) Fe
2
O
3
nanoparticle coated UF m...
Figure 8.11 Permeate flux profile in bentonite clay-coated UF membrane-assisted ...
Figure 8.12 Removal efficiency of various parameters observed in the bioprocess,...
Figure 8.13 Schematic of PMR.
Figure 8.14 (a) Hydrophobic surface modified ceramic capillary membranes (b) FES...
Figure 8.15 Surface microstructure observed in the FESEM of (a) MF support and (...
Figure 8.16 Surface microstructure observed in the FESEM of (a) MF support and (...
Chapter 9
Figure 9.1 Schematic presentation of MD configurations.
Figure 9.2 Schematic of AGMD/WGMD co-current module used by Amaya-Vías
et al
., 2...
Chapter 10
Figure 10.1 Schematic diagram of VMD.
Figure 10.2 Impact of feed temperature on permeate flux (reprint with permission...
Figure 10.3 Impact of vacuum degree on permeate flux (reprint with permission fr...
Figure 10.4 Impact of flow rate on permeate flux (reprint with permission from E...
Figure 10.5 SEM with EDS images of before and after use of PTFE membrane.
Figure 10.6 PSD analysis before and after use PTFE Membrane (reprint with permis...
Chapter 11
Figure 11.1 A schematic production process with waste stream [3].
Figure 11.2 Selection of location for wastewater sampling.
Figure 11.3 Samples before and after treatment at different conditions.
Figure 11.4 Effects of pH on the treatment efficiency of Cr (VI).
Figure 11.5 Effects of nano Fe
0
on the treatment efficiency of Cr(VI).
Figure 11.6 Effect of time on Cr (VI) treatment efficiency.
Figure 11.7 Effect of pH on the efficiency of heavy metal treatment.
Figure 11.8 Effect of PAC on the efficiency of heavy metal handling.
Figure 11.9 Effect of PAM on heavy metal removal efficiency.
Chapter 12
Figure 12.1 States and concentration of arsenic present.
Figure 12.2 Districts affected by fluoride-contaminated groundwater in different...
Figure 12.3 Different remediation technology of arsenic.
Figure 12.4 Treatment of arsenic-contaminated water by photo-oxidation method.
Figure 12.5 Conventional coagulation-flocculation-based arsenic mitigation techn...
Figure 12.6 Arsenic removal from contaminated water by ion exchange resin.
Figure 12.7 Conventional activated alumina-based arsenic treatment unit attached...
Figure 12.8 Nalgonda technique.
Figure 12.9 Conventional activated alumina-based adsorption treatment plant. Ado...
Figure 12.10 Pore size of various membranes and size of materials subject to fil...
Figure 12.11 Coagulation-microfiltration-based arsenic treatment unit (Wickramas...
Figure 12.12 Spiral wound–based nanofiltration process (Saitúa
et al
., 2005).
Figure 12.13 Schematic of the experimental unit for NF (Xia
et al
., 2007).
Figure 12.14 Schematics of nanofiltration pilot plant (Harisha
et al
., 2010).
Figure 12.15 Diagram of the nanofiltration pilot plant (Tahaikt
et al
., 2006).
Figure 12.16 Schematic diagram for fluoride and phosphate separation by a microf...
Chapter 13
Figure 13.1 (a) Number of desalination publications by categorisation (total, te...
Figure 13.2 Heat or work input for separation process.
Figure 13.3 (a) Least work of separation; (b) least heat of separation.
Figure 13.4 MSF-OT desalination system (adapted from ref. [18] with permission).
Figure 13.5 (a) Single-stage flash (b) the aspen plus model of single-stage flas...
Figure 13.6 Deaerator.
Figure 13.7 (a) Actual plant flowsheet (b) aspen plus flowsheet.
Figure 13.8 (a) MSF-OT with deaerator (b) MSF-OT without deaerator.
Figure 13.9 (a) Case I (b) case II (c) case III.
Figure 13.10 (a) Minimum energy demand in terms of heat and work for 35000 ppm a...
Figure 13.11 Effect of temperature on thermal energy.
Chapter 14
Figure 14.1 Resources recovery by chemical processes.
Figure 14.2 Schematic of a biological process for nutrients recovery.
Figure 14.3 The micro-algae culture reaction and resources recovery.
Figure 14.4 The membrane-based resources recovery processes.
Figure 14.5 Schematic of bio-electrochemical system.
Chapter 15
Figure 15.1 Map of ground water level in India 2019-20 (adapted from [12]).
Figure 15.2 Water stress in India 2015 (adapted from [17]).
Figure 15.3 Classification of water desalination technologies (adapted from [18]...
Figure 15.4 Schematic of reverse osmosis.
Figure 15.5 Schematic of electrodialysis (adapted from [39] with permission).
Figure 15.6 Schematic of membrane capacitive deionization (MCDI) (adapted from [...
Figure 15.7 Schematic of (a) Mechanical vapor compression (MVC) (b) Multi-stage ...
Figure 15.8 Map of solar radiation in India 2012 (adapted from [47]).
Figure 15.9 Schematic of single effect solar still (a) spherical solar still (b)...
Figure 15.10 Schematic of a photovoltaic (PV) cell (adapted from [60] with permi...
Figure 15.11 Geothermal sources in India (adapted from [68]).
Figure 15.12 Schematic of membrane distillation (adapted from [72] with permissi...
Figure 15.13 Schematic of forward osmosis (FO).
Chapter 16
Figure 16.1 A control volume representation of the desalination system.
Figure 16.2 A general multi-effect distillation (MED) desalination process schem...
Figure 16.3 Detailed components stream in i-th effect.
Figure 16.4 Detailed components stream in the i-th flash box.
Figure 16.5 Detailed components stream in i-th feed heater.
Figure 16.6 A typical multi-stage flash desalination process scheme [33].
Figure 16.7 A typical single stage mechanical vapor compression desalination pro...
Figure 16.8 Distribution of installed plant capacity according to the desalinati...
Figure 16.9 Flow sheet for energy use in single stage RO desalination operation.
Figure 16.10 Development of achievable energy consumption in RO desalination pro...
Figure 16.11 Cost evolution of SWRO process [38].
Figure 16.12 Cost composition for a representative seawater MSF plant. (Ebensper...
Figure 16.13 Cost composition for a representative seawater RO plant. (Ebensperg...
Figure 16.14 The relation between various forms of energy transfers (heat energy...
Figure 16.15 Schematic flow of RO-module based desalination plant for saline wat...
List of Tables
Chapter 1
Table 1.1 Comparison of AOP systems.
Chapter 2
Table 2.1 Overview of some previous works on combination of HC and chemical addi...
Chapter 3
Table 3.1 Summary of current applications of HC and other AOPs for treatment of ...
Chapter 4
Table 4.1 Different models of mass transfer in the liquid phase.
Table 4.2 Correlations for the mass transfer coefficients,
k
L
, from single gas b...
Table 4.3 Energetics database.
Table 4.4 Different applications based on ozone treatment irrespective of pilot ...
Chapter 5
Table 5.1 A comprehensive summary of the performance of NPs and NCs in removing ...
Table 5.2 A comprehensive summary of the performance of NPs and NCs in removing ...
Chapter 6
Table 6.1 Examples of a few pollutants found in wastewater and the health hazard...
Table 6.2 Example of various metal oxide nanoparticles used in wastewater treatm...
Table 6.3 Recent literature on wastewater treatment using MIP.
Chapter 7
Table 7.1 Materials used for the preparation of cathode.
Table 7.2 Materials used for the preparation of anode.
Table 7.3 Materials used for the preparation of membrane.
Table 7.4 Different sources of wastewater used in MFC.
Chapter 8
Table 8.1 Application of ceramic membranes for industrial wastewater treatment.
Table 8.2 Application of ceramic membranes for contaminated groundwater and drin...
Table 8.3 Classification of types of membranes used in water and wastewater trea...
Chapter 9
Table 9.1 Some studies carried out by researchers for acidic wastewater treatmen...
Table 9.2 Hybrid MD processes for acidic effluent treatment carried out by some ...
Chapter 11
Table 11.1 Water used and wastewater generated from a general small metallurgica...
Table 11.2 The bath tests used in this study.
Table 11.3 The analysis procedures used in this work.
Chapter 12
Table 12.1 Chemicals used in different arsenic precipitation processes (Jing et ...
Table 12.2 Arsenic removals by recently developed or surface modified adsorbent ...
Table 12.3 Removal efficiency of As(III) and As(V) by different NF membranes.
Table 12.4 Removal efficiency of fluoride by different NF membranes.
Chapter 13
Table 13.1 Input variables of MSF-15 stages.
Table 13.2 Input variables of MSF-15 stages.
Table 13.3 Input variables of steam.
Table 13.4 Seawater composition.
Table 13.5 Input parameters of crystallizer.
Table 13.6 Thermal energy & water recovery (%).
Table 13.7 Requirement of thermal energy on integration of crystallizer with MSF...
Table 13.8 Crystallization of salts.
Chapter 14
Table 14.1 Literature data on nutrients recovery through chemical precipitation.
Table 14.2 Literature data on the ionic concentration of MAP required reaching s...
Table 14.3 Literature data on adsorption of nutrients using different adsorbents...
Table 14.4 Literature data on nutrients recovery from microalgae.
Table 14.5 The literature data on resources recovery from membrane based process...
Table 14.6 Literature data on recovery of bio-energy and nutrients from waste wa...
Table 14.7 Summary of the resource’s recovery processes.
Chapter 16
Table 16.1 Comparison of the desalination process by thermal and membrane techno...
Table 16.2 Different energy requirements in desalination techniques in plant [42...
Table 16.3 Cost of desalinated water in thermal processes [37].
Table 16.4 Cost of desalinated water in the membrane (RO) Plants [37].
Table 16.5 Cost with relative to RO [38].
Guide
Cover
Table of Contents
Title Page
Copyright
Introduction
Begin Reading
Index
Also of Interest
End User License Agreement
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Sustainable Water Treatment
Advances and Technological Interventions
Edited by
Siddhartha Moulik
Aditi Mullick
and
Anirban Roy
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Library of Congress Cataloging-in-Publication Data
ISBN 9781119479987
Cover image: Pixabay.ComCover design by Kris Hackerott
Set in size of 11pt and Minion Pro by Manila Typesetting Company, Makati, Philippines
Printed in the USA
10 9 8 7 6 5 4 3 2 1
Introduction to Water Treatment: A Historical Perspective on Technological Development and Future Landscape
Anirban Roy1*, Anupam Mukherjee1, Aditi Mullick2 and Siddhartha Moulik2†
1Water-Energy Nexus Lab, Department of Chemical Engineering Goa, BITS Pilani, Goa, India
2Cavitation and Dynamics Lab, Process Engineering and Technology Transfer Division, Indian Institute of Chemical Technology, Hyderabad, India
Abstract
Efficient water production, recovery, recycling and management underlines the degree of sustainability of the resource. In the last decade, water has been considered as the “new oil” and as the popularity of non-renewable energy sources are slowly starting to fade, there is no alternative to water. In this regard, this book focuses on technological advances for water treatment in four categories: (i) advanced oxidation technologies, (ii) nanoparticles for water treatment, (iii) membrane separations, and (iv) other emerging technologies or processes. A wide variety of pollutants have also been discussed like acidic wastewater treatment, metallurgical wastewater, and textile wastewater as well as groundwater. More often than not, a stand-alone technology is not the solution for sustainability and one requires a process to be developed and technologies to be integrated. In this regard, the book will give valuable insights into both understanding of technologies as well as possible integration of technologies for a given waste stream to recycle and purify water.
Keywords: Advanced oxidation, membrane, nanoparticle, metallurgical wastewater, acidic wastewater, groundwater
Introduction
The current water crisis looming over a hapless human civilization can be attributed to (i) abuse of available sources of fresh water, (ii) wastage of water due to rapid urbanization and an improved quality of life, (iii) increased agricultural activities to feed an ever-growing population, depleting groundwater reserves, (iv) rapid industrialization, and (v) lack of coordinated policy implementations [1–3]. Adding to the woes, the current pandemic has challenged humanity like never before [4, 5]. This has posed a challenge of an entirely different nature, where water requirement for sanitization has increased manifold. The irreplaceable requirement of water in every sphere of life has made it imperative that to support an ever-increasing population, it is important to preserve, conserve, reuse and recycle the resource [6–9].
It is important to understand the technologies being employed to treat water in the current scenario. Water quality depends on the process it undergoes and therefore, depending on the constitutes of effluent stream, proper strategy can be framed and suitable process with minimum energy penalty can be designed [10]. The maturity of individual technology with its application potential and energetics involved must be considered before making a choice for a desired purpose [7, 11].
In this regard, the current volume is a collection of chapters belonging to mainly four categories of technologies: (i) Advanced Oxidation Processes (AOP), (ii) Nanoparticle-Based Treatment (NPT), (iii) Membrane-Based Treatment (MBT), and (iv) Emerging Technologies and Processes (EMT).
In Section I (comprising AOP technologies), a general overview is presented in Chapter 1, where fundamentals related to AOP are discussed along with global trends. Popular AOP technologies like Fenton process, photocatalysis, ozone, ultraviolet (UV) and H2O2 are discussed in detail. Chapter 1 ends with challenges posed in AOP technologies. Chapter 2 delves into a different genre of AOP, Hydrodynamic Cavitation (HC). This chapter discusses the mechanisms of ultrasound and HC processes and delves deep into integration of cavitation technologies with existing wastewater treatment technologies. The chapter also deals with integration of HC with adsorption and chemical oxidation processes and ends with future perspective of HC. Chapter 3 deals with a different aspect of HC, where, bubble dynamics, bubble collapse and thermodynamic effects of HC have been discussed. This gives an in-depth understanding of cavitation phenomena. The chapter also discusses various cavitating reactors and the toxicity effects of treatment process; it ends with future avenues. Chapter 4 (the last chapter in AOP) discusses fundamentals of ozonation technology. This chapter deals with various mass transfer models and mass transfer mechanism of ozone in water. The chapter handles the topic of ozone as a gas liquid contacting system and discusses the related mechanism as well as energetics associated. In the last part, the chapter deals with various sectors of application of ozone.
Section II of the book deals with NPT and in this regard, chapter 1 discusses application of Nanoparticles (NP) in fixed bed column filter system. This chapter discusses various target contaminants and the type of NP used to remove those contaminants. Then the chapter deals with design of fixed bed columns using the NP for removal of pollutants. Chapter 2 discusses the potential of NP-based water treatment processes. This chapter deals with various types of NPs employed to remove specific pollutant streams and the barriers posed in large-scale implementations.
Section III deals with membrane-based technology. In this regard, chapter 1 discusses microbial fuel cell (MFC) technology for wastewater treatment. This chapter discusses fundamentals related to working of an MFC and recent developments in anode and cathode material development. It also discusses development of membranes for MFC and challenges in MFC, and ends with case studies. Chapter 2 discusses the potential applications and challenges of ceramic membrane filtration. This chapter discusses the application of various ceramic membranes in industrial wastewater treatment as well as emerging contaminants. It also discusses the various configuration variants of ceramic membranes ultimately ending with pilot scale studies and challenges of ceramic membrane filtration units. Chapter 3 discusses an emerging area in the field of membrane separation—membrane distillation (MD). This chapter discusses the possibility of acidic wastewater treatment using MD. This chapter deals with the basics of the origin of acidic wastewater as well as various MD technologies employed in practice. This chapter also discusses various hybrid MD processes ultimately concluding with implications of MD in acidic wastewater treatment. The last chapter in this section (Chapter 4) discusses long-term assessment of vacuum membrane distillation (VMD) for textile wastewater treatment. This chapter covers the basics of transport mechanism and mass transfer involved in VMD and then discusses the influence of various operational parameters in textile wastewater treatment process in VMD.
The last section of the book is dedicated to few emerging processes in water treatment and recovery systems. Chapter 1 in this regard deals with application of zero valent iron to remove chromium and other heavy metals in metallurgical wastewater. This chapter deals with characterization of metallurgical wastewater in detail as well as preparation of zero valent iron. It then discusses in detail the batch experiments for treatment as well as detailed parametric investigations involved in treating the streams. The second chapter discusses removal of arsenic and fluoride using coagulation precipitation, ion exchange, and adsorption technologies. The chapter discusses detailed analysis of each genre of technology as well as its application and removal efficacies for arsenic and fluoride. The third chapter focuses on developing theoretical understanding of Zero Liquid Discharge (ZLD) process and its energy penalties. This chapter discusses in detail development of process flow sheet in Aspen and recovering maximum water from seawater feed using multistage flash coupled with evaporative crystallizer. This chapter discusses in detail development of the flow sheet and modeling of components along with energy analysis associated with a ZLD process for a feed whose salinity is equal to that of seawater. The fourth chapter focuses on a self-consistent approach in developing a water - energy - food nexus with an objective of highlighting the prospects and challenges in “conceptualization to technology transfer” for nutrient recovery from municipal wastewater for sustainable resource recovery and waste water management. Wastewater today is considered as a resource because of abundance of nutrients present in it. These nutrients like phosphorous and nitrogen if could be extracted economically, have the potential to solve multiple problems such as reutilization of natural resources and reduction in eutrophication in water bodies. In this regard the methods of extraction, based on the laws of thermodynamics shall be utilized for the same in order to maintain the crafted balance of water-energy-food nexus (WEFN). Throughout the chapter, nutrients, biomass, energy, and water are collectively termed as resources. The fifth and sixth chapter in this section highlights towards sustainable desalination. Desalination has largely been limited to affluent countries in the Middle East and has recently started making inroads in parts of the United States and Australia. In this regard, the initial efforts was to highlight the growing opportunities and scopes in the Indian subcontinent, while in the last chapter authors discussed on the least energy (work, heat, and fuel) required for desalination establishing a benchmark using the first and second laws of thermodynamics.
This book has been edited to bring forth a broad perspective in understanding the various state-of-the-art technologies being employed or developed in laboratory scale in treating a wide range of water stream and hopefully will benefit a broad section of readers.
Acknowledgement
Dr. Siddhartha Moulik would like to thank the Director, CSIR-IICT for the support [Ref. IICT/Pubs./2022/110].
References
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Section IADVANCED OXIDATION PROCESSES
1Advanced Oxidation Processes: Fundamental, Technologies, Applications and Recent Advances
Akshat Khandelwal and Saroj Sundar Baral*
Department of Chemical Engineering, BITS Pilani K K Birla Goa Campus, Goa, India
Abstract
Water waste globally triggers warnings, since a majority of the population has no access to clean potable water. Vast amounts of synthetic organic pollutants such as toxic chemicals, pesticides, pharmaceutical products and personal care products have been reported to be released into water supplies daily. Advance oxidation process (AOP) involves formation of reactive oxygen species which are very reactive and non-selective, and can degrade these hazardous compounds to CO2 and inorganic ions. It can potentially reduce pollutant concentrations from hundreds of parts per million (ppm) to only a few parts per billion (ppb). As new developments in wastewater treatment, TiO2, photocatalysis, Fenton and photo-Fenton approaches have appeared. This chapter discusses the fundamentals and role of the AOP in wastewater remediation. Further, background and global research trends of wastewater treatment employing AOP are discussed. Moreover, different AOP technologies along with challenges restricting their full-scale operation are addressed in detail.
Keywords: Advanced oxidation processes (AOC), photocatalysis, fenton, photo-fenton, effluent treatment, reactive oxygen species
1.1 Introduction
Water is a finite resource that is important for sustainable growth. While abounding on Earth as saltwater from the oceans and seas, only 1% is readily accessible for human consumption. Our society needs convenient access to more and more safe drinking water. Worldwide water pollution is raising alarms as 780 million people do not have access to safe drinking water [1]. Water contamination continues to be an omnipresent danger as vast amounts of synthetic organic contaminants, like industrial, agricultural, pharmaceutical chemicals and personal care products, are reported to be released on a daily basis into water streams [2, 3]. For this wastewater, treatments are necessary. After the treatment still, some pollutants are highly stable and are resistant to radiation, temperature and microbial decomposition [4–6]. These contaminants can be termed as pertinent organic pollutants that cannot be easily treated in a conventional wastewater treatment plant. Moreover, pertinent compounds possess unknown characteristics that raise a great threat to environmental and human health.
Wastewater management technology has seen a recent and conclusive awakening, and today’s attention centers on designing quick, safe, reliable and cost-effective solutions to decompose POPs before disposal. A thorough overview of available eco-friendly approaches widely used for wastewater treatment techniques is provided in detail in many reviews [4–8]. In addition, in some literature these methods can be split into two groups: (i) physicochemical separation system, for example, membrane separation, and (ii) chemical and microbiological driven transformation systems. Transformation technologies are quite effective as they cleave the dangerous pollutants into less harmful compounds. In this chapter, we are going to deal with the advance oxidation process and its role in wastewater treatment.
Advanced oxidation processes (AOPs) can effectively degrade pollutants into least dangerous substances by oxidising toxic compounds. AOP are the oxidation processes that are connected to reactive oxygen species formation, such as hydroxyl radicals. Hydroxyl radical is widely explored in AOP as it is the second-strongest oxidising agent behind fluorine, with a standard reduction potential of 2.8 V/SHE. Moreover, hydroxyl radical is highly reactive and non-selective and can cause harmful materials to degrade to CO2 and inorganic ions. Therefore, these radical hydroxyls can be used to degrade various wastewater effluents from industry and agriculture.
There are different approaches to bring in different effects when using multiple technologies. Specifically, ozone, hydrogen peroxide, and ultraviolet light are commonly used to create adequate levels of hydroxyl radical that can be used to degrade some organic and inorganic contaminants. Pollutant concentrations can be lowered by AOP, theoretically from hundreds of parts per million (ppm) to just a few parts per billion (ppb). As new developments in wastewater treatment, TiO2, photocatalysis, Fenton and photo-Fenton approaches have appeared. These AOPs are added to the purification and detoxification of many toxic waste materials containing pharmaceutical products. Photocatalysis and photo-Fenton are also suggested in urban effluent as tertiary remediation. Removing targeted micro-pollutants, such as naproxen, carbamazepine, diclofenac, gemfibrozil, ibuprofen, caffeine and mecoprop, was recorded with photolysis and ultraviolet/hydrogen gas processes. The average levels of oxidation for organic compounds are improved by the inclusion of hydrogen peroxide. They may be employed to eradicate the non-biodegradable contaminants after the biological procedure. Electrochemical AOPs, plasma, electron beam, ultrasound, and even micro-wave dependent AOPs have also been suggested and are commonly being recorded by researchers. However, a wide range of research, as well as a growing array of proposed innovations and process combinations, make it difficult to determine current AOPs cost, chemical inputs and sustainability. Also, the water matrix might impact radical generation processes, such as reducing UV defence or reactions with ozone.
Therefore, this chapter provides a critical summary of the numerous current and emerging AOPs based on data gathered from comprehensive literature survey. The purpose of this chapter is to provide readers with general understanding of the fundamentals of AOP. We explored the background and global trends of AOPs. Various AOP innovations are addressed in the next section, followed by a thorough comparison between them. Moreover, challenges to these AOP technologies are discussed side by side.
1.2 Background and Global Trend of Advanced Oxidation Process
The advanced oxidation process (AOP) employs the formation of highly reactive oxidizing radicals for example hydroxyl radical (OH.), sulphate radical (SO42-), hydroperoxyl radical (HO2·), etc., at ambient temperature and pressure in the solution for the degradation of pertinent organic pollutants (POPs) in the waterbodies. AOP set its footmark in the wastewater treatment process in 1987 when Glaze et al. defined AOP as “the process of forming suitable amount of OH.radical for effective treatment of wastewater” [9, 10]. Initially, AOP studies were limited to the generation of •OH radical but later on degradation employing sulphate radicals was also explored [11, 12].
Various techniques have been studied to destroy compound aromatics such as phenols, chlorophenols, and nitrophenols by AOPs. The findings reveal that under optimal conditions, high removal efficiency can be achieved. Studies have been carried out evaluating the impact of certain operating parameters on AOP. The degradation mechanisms, along with the influence of the variation in the molecular structure of aromatics on degradation performance, have been deduced and demonstrated in experiments. Moreover, textile colouring may have adverse effects on microorganisms, marine life and human beings. These colouring dyes limit the penetration of light into polluted water. The decolorization and oxidation of dyes have gained rising research interest. The research was conducted for analyzing the effect of operational characteristics, decolourisation, and degradation processes on the overall efficiency of AOP. However, the mechanism by which the AOP dyes are degraded is unclear, but some stable intermediates do form in the solution.
Over the years, the concentration of antibiotics has risen in wastewater. A variety of medical prescriptions drugs are consumed worldwide each year. These drugs may have harmful effects on the aquatic environment and even on terrestrial beings. Various forms of concerns have arisen following the elimination of these compounds and AOP has arisen as a promising technology for treatment of these pharmaceutical wastewaters. Moreover, research has been focussed on the effects of operational characteristics, the function of radical promoters and scavengers, as well as the effect of these parameters on the chemical composition of the waters.
In addition, AOP has shown potential for the treatment of wastewater containing pharmaceutical effluents. The primary use of pesticides in agriculture is to increase crop production. Surface water and groundwater may contain residues from the runoff of agricultural sites. A number of experiments have evaluated the effects of operational requirements in order to obtain optimum working conditions to remove pesticides from the wastewater using the AOPs. In these studies degradation mechanisms are postulated by determining the role of scavengers and identifying intermediate reactions. Moreover, AOP may also be used to detoxify other hazardous wastes, such as carboxylic acid, heavy metals, bacteria, and actual industrial wastewater. The operational conditions have been optimized using different interventions, and important effects on the reaction kinetics and degradation processes have been investigated.
Recently research was published highlighting the worldwide research trend of AOP in wastewater treatment [13]. The worldwide trend based on the number of research studies published in a year in the period 1990-2018 is shown in Figure 1.1a. Findings indicate that there has been a slow increase in annual publications for the period 1990-2002 while the growth for the period 2002-2018 has been significantly higher with a publication rate exceeding 25 articles per year, reaching a total of 450 articles published in 2018. Further country-wise comparison of several publications was done shown in Figure 1.1b. Eighty-six countries have published scientific papers in this area of research. However, the 13 most relevant countries correspond to about 85% of the publications in the region. Moreover, it was also seen in Figure 1.1c how China and Spain publish the largest amount of scientific papers on AOP wastewater treatment, and how five Chinese and three Spanish institutions lead the scientific output in this field, with the CIEMAT-Solar Platform of Almeria leading the ranking.
Figure 1.1 (a) The annual trend in the number of advanced oxidation process publications from 1990-2018. (b) Representation of the countries with the largest number of advanced oxidation process publications. (c) Major organizations relevant to scientific development in the advanced oxidation process of wastewater. Reproduced from ref [13].
1.3 Advanced Oxidation Systems
Heterogeneous TiO2-based photocatalyst and homogeneous photo-Fenton-based catalyst, under on UV or solar, visible irradiation, electrochemical AOPs, ozonation, Fenton, sonolysis, ionizing beam and μ-radiolysis radiation, microwaves, pulsed plasma is widely used for wastewater treatment. However, it is worth noting that the system of grouping shown in Figure 1.2 cannot be regarded as rigid as some systems require multiple methods and may thus be delegated to separate categories.
Figure 1.2 Classification of AOP systems.
1.3.1 Ozone-Based AOP
There are ozone-based AOPs that are activated in combination with ultraviolet light, hydrogen peroxide, catalysts and ultrasound [14]. These types of systems are excellent for oxidising hazardous organic water pollutants that are not targeted by chlorine and ozone. O3/UV is an effective technology for the removal of refractory contaminants. The procedure is initiated by ozone photolysis and accompanied by the creation of hydroxyl radical. The effects of pH on the decolorization of reactive red 2 by O3, O3/Fe(II), UV/O3 and UV/O3/Fe(II) systems were examined [15]. The result indicates that at all pH, O3/UV system promotes reactive red 2 degradations. Besides, only at pH=4 can O3/Fe(II) and UV/O3/Fe(II) structures exert synergistic effects. An experiment has been carried out to study the ozonation of urban wastewaters [16]. Results show that the addition of H2O2 promotes the degradation of Para-chloro-benzoic acid. Moreover, a threshold dosage value of H2O2 is specified below which there is no increase in the rate of degradation. Also, catalytic ozonation is attracting considerable interest as an important method for extracting organics from water [17]. Much is still unclear about the dynamics of catalytic processes. In order to have this methodology for industrial-scale consumption, one must provide an understanding of the mechanisms. As an example in the ozonation of oxalic acid in the water, two iron catalysts were used at pH 2.5 [18]. The process will probably evolve by the creation of iron-oxalate complexes that react further with ozone without hydroxyl radicals.
In the heterogeneous process, some liquidation of metal was detected and quantified due to the stringent acidic conditions. The authors assume that the method leads to full mineralization in any event. In addition heterogeneous catalytic ozonation also showed potential for the degradation of refractory contaminants. For example, magnesium Iron Tetroxide (MgFe2O4) was successfully synthesized and used in ozonation for degradation of Acid Orange II (AOII) [19]. Over a broad pH spectrum of 4.6-9.6, the degradation performance of AOII approaches 90%, marginally influenced by the solution pH. Mg role in MgF2O3 was to maintain the high electron density on lattice oxygen. Carbon-based materials were also utilized for catalytic ozonation for the degradation of organic pollutants. The research assessed the impact of nitrogen doping on carbon nanofibers’ catalytic activity [20]. Findings indicate that the inclusion of N-containing functionalities on the surface of the carbon nanofibers improves their catalytic properties.
1.3.2 UV/H2O2
The implementation of UV-based processes is likely to address the concern about the effect of micro-pollutants on the quality of drinking water [21]. The efficacy of UV processing approaches for handling pharmaceuticals is heavily dependent on their UV absorbance [22–24]. Also important parameters in the degradation of organic contaminants by UV light are the rate constants, quantum yield, and molar extinction coefficient [25]. UV along with H2O2 increases the effectiveness of separation from contaminants with low UV absorption. UV/H2O2 processes are regulated by the H2O2 concentration, the rate of HO radical formation, the UV light strength, the water constituents and the chemical composition of the pharmaceutical [25]. UV/H2O2 process was reported to moderately yield reduction in the concentration of volatile organic compounds (VOC) with degradation efficacy higher than 80% [26]. The superior efficiency of UV/H2O2 is attributed to the formation of hydroxyl radicals. UV/H2O2 can be used for the treatment of VOCs with effective and environmentally safe technologies. UV photolysis of hydrogen peroxide is a traditional advanced oxidation technique. Substitution of peroxide by HOCl promises cost-effectiveness [27]. In an experiment, the effects of pH and the molar ratio of a pollutant to an active chlorine ingredient on the UV dependent method were tested using 1,4-dioxane as a model pollutant [28]. According to the UV/HOCl/photolytic optimum pH in range of 3–6 was found. The reaction efficiency at a high molar ratio of initial chlorine to initial HOCl exceeded 100% at a pH of 3 to 6, implying feasibility of photolysis-UV/HOCl AOPs. UV along with photocatalytic method was employed to treat wastewater taken from anaerobic sedimentation tank [29]. The results indicate that the optimal UV power of 20 W could be used for the process’s time needed for the optimal TiO2dose with a contact time of 110 min.
1.3.3 Radiation
The use of electron beam irradiation has been tested since the 1980s for water treatment. Accelerated electrons enter the water surface producing electro-excited species, including ions and free radicals [25]. Gamma irradiation, unlike UV processes, is more penetrating and promotes the increased development of hydroxy radicals and hydrated electrons to support successful contaminant breakdown. In addition, the energy of the electrons concerned is directly proportional to the degree of penetration. Therefore, water is either radiated as a thin film or as an aerosol. This method due to high oxidising power and low interaction with the water matrix was found to be very successful in degrading many contaminants [25].
The effect of single gamma radiation in peroxy-monosulfate activation for carbamazepine degradation was explored. The results showed that the addition of peroxy-monosulfate caused carbamazepine oxidation, which was due to the formation of hydroxyl, per hydroxyl radicals and superoxideradical anions. Further research has been conducted on the feasibility of the integration of electron beam radiation and hydrogen peroxide. The result indicates a 90% deterioration in the absence of H2O2 at a dosage of 1 kGy. Oxidation has increased in this situation by adding H2O2 (10 mM concentration). Moreover, a rise in H2O2 concentrations from 50 to 200 mM resulted in a reduction in the deterioration rates suggesting the importance of concentration of H2O2. To show the efficacy of fluoxetine degradation, a minimal irradiation dosage of 0.5 kGy proved to be highly efficient. In a wastewater treatment plant electron beam therapy using a linear electron accelerator successfully improved bacterial resistance to antibiotics. This has been shown by Szabo et al. in the elimination of piperacillin’s antimicrobial action [30]. Owing to the high capital expense, the safety processes of an electron accelerator and the risks involved with rays, gamma rays and the electron beam process are not yet profitable.
Extremely energetic microwaves were also studied for the elimination of water pollutants. In order to promote the degradation of organic pollutants, the microwaves were combined with oxidants such as hydrogen peroxide and catalysts such as TiO2 [31–33]. Microwaves can not only boost degradation rates of contaminants but also aid in the heating of particular contaminants. Unsurprisingly, microwaves offer low electrical efficiency as most energy gets converted to heat. Often, cooling equipment has to be utilized to ensure that the filtered water does not overheat.
Another component of AOP is ultrasound irradiation, also known as sonolysis [34, 35]. This is based on the radical hydrolysis of water due to the high strength of acoustic cavity bubbles, thus creating hydroxyl radicals from water. Sonication of water by ultrasound contributes to the creation and collapse of micro-bubbles leading to mediated acoustical wave compression and rarefaction. Upon passing a certain point, these bubbles implode violently and erupt with tremendous intensity. Water toxins are destroyed by decomposition and various reactive chemical reactions. Ultrasound irradiation experiences minimal interference from the water matrix and less heat transfer compared to UV irradiation. A degrading process of a known water pollutant, coomassie brilliant blue (CBB), has been performed in pure water and river water via ultrasound AOP [36]. The oxidation was carried out in the presence of inorganic ions such as chloride, sulphate, nitrate, bicarbonate, and carbonate ions. A potential degradation mechanism is suggested based on the product profile calculated by liquid chromatography-quadrupole-time-of-flight mass spectrometry. The poor productivity of oxidation of river water relative to that in pure water is mostly due to high levels of dissolved oxygen scavenging of hydroxyl radical by organic material and erosion of bubbles by dissolution.
1.3.4 Fenton Reaction
The potential use of a combination of H2O2 and Fe2+ to destroy tartaric acid was pointed out by Fenton in 1876. A radical mechanism for the catalytic decomposition of H2O2 by iron salts was introduced in the 1930s by Haber and Weiss [37, 38]. Mechanistic experiments about Fenton reaction since then have been extensively documented in reaction chemistry [39, 40]. The Fenton reaction takes advantage of iron salts and hydrogen peroxide to yield hydroxyl radicals.
In photo-Fenton technology photo-assisted reduction of Fe(III) takes place (at pH 2.8–3.5) under UV and visible light irradiation [40]. Quantum efficiency of photo-Fenton process is quite low, therefore to increase the quantum efficiency organic ligands are been employed [41]. For example, ferrioxalate which can absorb radiation up to 550 nm displays a good UV light absorption resulting in improved quantum efficiency [30].
Homogeneous photo-Fenton process
Both Fenton and photo Fenton processes are successful for pharmaceuticals degradation. It has been shown that low concentrations of Fe2+ effectively degrade 100 mg/L ofloxacin and trimethoprim [42]. Moreover, the photoFenton performance was influenced by the water composition specifically during the elimination of 5-Fluorouracil from industrial effluent [43]. A combination of ultrasonic irradiation to the Fenton and photo-Fenton process can be considered as a good choice for degrading phenol derivatives obtained from petrochemical plants wastewater [44]. The electro-Fenton procedure is an evolving treatment technology. Fortunately, this approach is extremely effective in handling recalcitrant compounds that are not readily degradable. The electro-Fenton method for degradation of benzene, toluene, and p-xylene using the sacrificial precious metal, iron, and steel anodes attained 96.4%, 88.7%, and 87.6% removal efficiencies respectively at an initial concentration of 150 mg/L [45]. When the analysis was completed, treatment for one cubic meter of polluted water cost as much as $1.40 with the electro-fenton procedure. Moreover, degradation of reactive Black 5 dye and phenanthrene was tested in an electro-Fenton reactor, using the electricity provided by the microbial fuel cell. The findings allow for the conclusion that the integrated system is adequate in wastewater remediation to achieve high treatment performance with low electrical usage [46].
1.3.5 Photocatalytic
In recent decades the application of photocatalytic materials in water oxidation processes has been explored widely [47, 48]. Even though there are several alternative catalysts, studies centered on TiO2 based photocatalyst.
Heterogeneous photocatalytic reaction
In heterogeneous TiO2-based photocatalysis, when the light of sufficient wavelength (greater than the wavelength of photocatalyst) strike semiconductor, electrons and holes are generated in conduction and valence band, respectively. These generated charge species then promote surface oxidation and reduction reaction of water constituents. Photocatalyst technology faces the challenge of poor light absorption and faster recombination of charge species which result in low quantum yield [49]. The addition of an electron donor will restrict the migration of holes and will reduce the recombination rate. For example, addition of citric acid to TiO2 based photocatalyst restricts the charge recombination by filling the holes [50].
