Wastewater Treatment Technologies E-Book

Mritunjay Chaubey

• Herausgeber: John Wiley & Sons
• Kategorie: Fachliteratur
• Serie: Challenges in Water Management Series
• Sprache: Englisch

Seitenzahl: 446

Veröffentlichungsjahr: 2021

Beschreibung

WASTEWATER TREATMENT TECHNOLOGIES Globally, the practice of wastewater treatment before discharge is inconsistent. The United Nations World Water Development Report (2017) estimated that, globally, over 80% of all wastewater is discharged without treatment. The discharge of untreated or inadequately treated wastewater into the environment results in the pollution of surface water, soil and groundwater. According to the WHO, water-related diseases kill around 2.2 million people globally each year, mostly children in developing countries. We need to understand that wastewater is not merely a water management issue - it affects the environment, all living beings, and can have direct impacts on economies. The establishment of UN Sustainable Development Goal 6 (Clean Water and Sanitation), which aims to ensure availability and sustainable management of water and sanitation for all, reflects the increased attention on water and wastewater treatment issues in the global political agenda. Water reuse is one of the most efficient, cost effective and eco-friendly ways to ensure water resilience. Embedding sustainability into wastewater treatment is the best opportunity for industries to drive smarter innovation and efficient wastewater treatment. The modern concept of industrial wastewater treatment is moving away from conventional design. Wastewater treatment technology is moving towards extreme modular design using smart and sustainable technology. This book is intended as a reference book for all wastewater treatment professionals and operational personnel. It may also be used as a textbook on graduate and postgraduate courses in the field of wastewater treatment and management. The book takes a holistic view of the practical problems faced by industry and provides multiple needs-based solutions to tackle wastewater treatment and management issues. It elaborates on selection of technology and their design criteria for different types of wastewater. This will enable engineering students and professionals to expand their horizons in the fields of wastewater treatment and management.

Leseprobe

Table of Contents

Cover

Series Page

Title Page

Copyright Page

Series Editor Foreword – Challenges in Water Management

Preface and Acknowledgments

List of Abbreviations

1 Global Perspective of Wastewater Treatment

1.1 Global Wastewater Treatment Scenario

1.2 The UN Sustainable Development Agenda for Wastewater

1.3 Global Market Size

1.4 Global Best Practices

1.5 Embedding Sustainability into Wastewater Treatment

1.6 Sustainable Sources for Industrial Water

1.7 Deep Sea Discharge as an Alternative to Minimize Human and Environmental Health Risks

1.8 Environmental Rule of Law

1.9 Trends in Wastewater Treatment Technology

References

Further Reading

2 Wastewater Characteristics

2.1 Wastewater Characteristics of Various Industries

2.2 Wastewater Characteristics and Measuring Methodology

Further Reading

3 Wastewater Treatment Technologies

3.1 Overview of Wastewater Treatment Technologies

3.2 Primary Treatment

3.3 Secondary Treatment

3.4 Tertiary Treatment

3.5 Sludge Dewatering

3.6 Zero Liquid Discharge

References

Further Reading

4 Design Considerations

4.1 Screening

4.2 Equalization Unit

4.3 Dissolved Air Flotation

4.4 Clariflocculator

4.5 Conventional Activated Sludge

4.6 Moving Bed Biofilm Reactor

4.7 Membrane Bioreactor

4.8 Chlorination Unit

4.9 Pressure Sand Filter

4.10 Activated Carbon Filter

4.11 Ultrafiltration

4.12 Reverse Osmosis

4.13 Evaporator with Crystallizer

4.14 Filter Press

4.15 Belt Press

4.16 Centrifuge

4.17 Gravity Thickener

Further Reading

5 Advance Sustainable Wastewater Treatment Technologies

5.1 Scaleban

5.2 Forward Osmosis

5.3 Activated Glass Media Filter

5.4 Vacuum Distillation

5.5 Volute

5.6 Solar Detoxification

5.7 Sustainable Wastewater Treatment

References

Further Reading

6 Zero Liquid Discharge

6.1 ZLD Technologies

6.2 ZLD Technologies: Techno‐Economic Evaluation

6.3 Feasibility Study of ZLD

Further Reading

7 Wastewater Treatment Plant Operational Excellence and Troubleshooting

7.1 Wastewater Treatment Issues

7.2 Wastewater Stream Identification, Characterization, and Segregation

7.3 Operation and Troubleshooting for Preliminary Treatment System

7.4 Operation and Troubleshooting for Primary Treatment System

7.5 Operation and Troubleshooting for Secondary Biological Treatment System

7.6 Operation and Troubleshooting for Tertiary Treatment System

7.7 Wastewater Sampling

7.8 Operation Records and Daily Log Sheet

7.9 Microbiology Fundamentals

7.10 Biological Wastewater Treatment Factors

7.11 Lab Testing Activity and Support

7.12 Best Practices for Pipe Line Sizing

7.13 Best Practices for Instrument Operation

7.14 Wastewater Online Monitoring Process

7.15 Wastewater Characteristics Monitoring Parameters

7.16 Effluent Treatment Plant Operating Procedure

Further Reading

Glossary

Index

End User License Agreement

List of Tables

Chapter 1

Table 1.1 Average cost of wastewater treatment plants in chemical industries.

Table 1.2 Deep sea discharge outfalls for treated wastewater discharge.

Table 1.3 India vs US‐EPA norms for deep sea discharges for pesticide and pha...

Chapter 2

Table 2.1 Effluent characteristics of technical units of agrochemical industr...

Table 2.2 Low‐strength effluent characteristics of technical units of agrochemic...

Table 2.3 High‐strength effluent characteristics of technical units of agroch...

Table 2.4 Effluent characteristics of textile industries.

Table 2.5 Effluent characteristics of pharmaceutical manufacturing industries...

Table 2.6 Low‐strength effluent characteristics of pharmaceutical manufacturing ...

Table 2.7 High‐strength effluent characteristics of pharmaceutical manufactur...

Table 2.8 Effluent characteristics of heavy metal processing industries.

Table 2.9 Major wastewater streams.

Table 2.10 Effluent characteristics of oil refining operations.

Table 2.11 Effluent characteristics of petrochemical manufacturing industries.

Table 2.12 Effluent characteristics of spent caustic effluent streams.

Table 2.13 Effluent characteristics of gas well exploration operations.

Table 2.14 Effluent characteristics of pulp and paper industries.

Table 2.15 Effluent characteristics of sugar industries.

Table 2.16 Effluent characteristics of distillery industries.

Table 2.17 Effluent characteristics of dairy industries.

Table 2.18 Wastewater characteristics of ice cream manufacturing.

Table 2.19 Wastewater characteristics of home care industries.

Table 2.20 Wastewater characteristics of personal care industries.

Table 2.21 Wastewater characteristics of spreads and dressings industries.

Table 2.22 Wastewater characteristics of savory fooods industries.

Table 2.23 Wastewater characteristics of oral (mouth and teeth cleaning) industr...

Table 2.24 Wastewater characteristics of deodorant industries.

Table 2.25 Effluent characteristics of fruit‐based products processing indust...

Table 2.26 Effluent characteristics of fertilizer industries.

Table 2.27 Effluent characteristics of paint manufacturing industries.

Table 2.28 Effluent characteristics of cement plants.

Table 2.29 Effluent characteristics of thermal power plants (cooling tower bl...

Table 2.30 Effluent characteristics of the smelter process.

Table 2.31 Characteristics of raw domestic sewage.

Table 2.32 Phosphorus range and wavelength.

Table 2.33 Water hardness scale.

Chapter 3

Table 3.1 Usual bar sizes and openings of manually cleaned bar screens.

Table 3.2 Design parameters of various types of pressure filters.

Table 3.3 Fouling prevention techniques of RO systems.

Chapter 4

Table 4.1 Main process parameters for screening unit.

Table 4.2 Main process parameters for equalization tank.

Table 4.3 Main process parameters for DAF units.

Table 4.4 Chemicals application with pH range.

Table 4.5 Main process parameters for clariflocculators.

Table 4.6 Main process parameters for biological reactors.

Table 4.7 Characteristics of a typical secondary clarifier.

Table 4.8 Main process parameters for MBBR technology.

Table 4.9 Main process parameters for biological reactors.

Table 4.10 Characteristics of a typical reference ultrafiltration membrane bi...

Table 4.11 Operational parameters with two cassettes and one cassette (1500 m

Table 4.12 Ultrafiltration membranes specification.

Table 4.13 Main process parameter for chlorination basin.

Table 4.14 Main process parameters for PSF unit.

Table 4.15 Main process parameters for GAC filters.

Table 4.16 Main process parameters for UF unit.

Table 4.17 UF membranes typical operating conditions.

Table 4.18 UF skids shutdown summary.

Table 4.19 Main process parameters for RO unit.

Table 4.20 Characteristics of First Stage RO Membranes.

Table 4.21 Characteristics of Second Stage RO Membranes.

Table 4.22 Recommended RO cleaning chemicals.

Table 4.23 Recommended flow and pressure of RO chemical cleaning solution.

Table 4.24 Recommended temperature and pH range of RO chemical cleaning solut...

Table 4.25 Size and material of constructions of RO chemical cleaning equipme...

Table 4.26 Main process parameters for evaporator with crystallizer.

Table 4.27 Main process parameters for filter press unit.

Table 4.28 Main process parameters for belt press unit.

Table 4.29 Main process parameters for centrifuge unit.

Table 4.30 Main process parameters for gravity thickener.

Chapter 5

Table 5.1 Main process parameters of AGF.

Table 5.2 AGF product specifications.

Table 5.3 Grades and arrangement from top to bottom in AGF.

Table 5.4 Brief comparison of vacuum distillation and MEE technology.

Table 5.5 Extraterrestrial radiation supplied by the sun.

Table 5.6 Calculated wavelength corresponding to various energy band gaps of ...

Table 5.7 Oxidation potentials of common substances for pollution abatement.

Table 5.8 Major properties of titanium dioxide.

Chapter 6

Table 6.1 Operation and troubleshooting of MEE system.

Table 6.2 Untreated and treated WW characteristics.

Table 6.3 Feasibility study to meet discharge norms and ZLD norms.

Chapter 7

Table 7.1 Aeration tank volume, air requirement, and blower capacity calculat...

Table 7.2 Sludge production calculations from an aeration system.

Table 7.3 F/M ratio calculations.

Table 7.4 Temperature classification of biological processes.

Table 7.5 Typical operating parameters for ASU, DNB, and INDB.

Table 7.6 Troubleshooting for aerobic systems.

Table 7.7 Flow velocity for sand filter and activated carbon filter.

Table 7.8 Recommended RO cleaning chemicals.

Table 7.9 Recommended flow and pressure of RO chemical cleaning solution.

Table 7.10 Recommended temperature and pH range of RO chemical cleaning solut...

Table 7.11 Size and material of construction of RO chemical cleaning equipmen...

Table 7.12 Three kingdoms of microorganisms

Table 7.13 Simplified biochemical exothermic reactions for autotrophic and he...

Table 7.14 Minimum quantity of equipment for a lab testing facility.

Table 7.15 Flow velocity for pump suction and pump discharge.

Table 7.16 Online monitoring industry‐specific parameters.

Table 7.17 Wastewater characteristics parameters.

Table 7.18 Effluent treatment plant operating procedure.

List of Illustrations

Chapter 1

Figure 1.1 Global wastewater treatment scenarios.

Figure 1.2 UN Sustainable Development Goals.

Figure 1.3 The global market size of water and wastewater technologies.

Figure 1.4 Best practices in wastewater treatment.

Figure 1.5 Wastewater stream segregation.

Figure 1.6 Operating cost composition of chemical industry wastewater treatm...

Figure 1.7 Scaleban equipment installed in a cooling tower.

Figure 1.8 Volute press equipment.

Figure 1.9 An MBBR plant.

Figure 1.10 Alternative sources for industrial water.

Figure 1.11 A deep sea discharge wastewater disposal system.

Figure 1.12 Wastewater treatment technology trends in industries.

Chapter 3

Figure 3.1 Wastewater treatment technologies at a glance.

Figure 3.2 A manually cleaned bar screen.

Figure 3.3 Schematic representation of a simple gravity O&G trap.

Figure 3.4 Schematic representation of an equalization tank.

Figure 3.5 Schematic diagram of a primary clarification unit.

Figure 3.6 Dissolved air flotation (DAF).

Figure 3.7 Schematic diagram of biological treatment.

Figure 3.8 Schematic diagram of activated sludge process.

Figure 3.9 Schematic diagram of activated sludge unit.

Figure 3.10 Schematic diagram of denitrification/nitrification biotreater un...

Figure 3.11 Schematic diagram of intermittent nitrification/denitrification ...

Figure 3.12 Schematic diagram of fixed film bioreactor plant.

Figure 3.13 MBBR technology process flow diagram.

Figure 3.14 Schematic diagram of a modern UASB reactor.

Figure 3.15 Working principle of OH radical technology.

Figure 3.16 System configuration of solar detoxification process.

Figure 3.17 Schematic diagram of separation process through semipermeable me...

Figure 3.18 Process diagram of reverse osmosis plant.

Figure 3.19 Schematic diagram of conventional biological fouling prevention ...

Figure 3.20 Simplified sludge treatment scheme (common treatment for biologi...

Figure 3.21 Sludge treatment scheme with anerobic digestion (common treatmen...

Figure 3.22 Schematic diagram of paddle sludge thickener.

Figure 3.23 Schematic representation of a sludge drying bed.

Figure 3.24 Typical shapes of anerobic digesters for sludge: (a) cylindrical...

Figure 3.25 Schematic representation of a plate and frame filter press.

Figure 3.26 Working of a typical volute.

Chapter 4

Figure 4.1 Schematic diagram of activated sludge unit.

Figure 4.2 Schematic diagram of denitrification/nitrification biotreater uni...

Figure 4.3 Schematic diagram of intermittent nitrification/denitrification b...

Figure 4.4 MBBR technology process flow diagram.

Figure 4.5 MBBR carrier media – high‐density polyethylene.

Figure 4.6 General arrangement of RO chemical cleaning equipment.

Chapter 5

Figure 5.1 Schematic diagram for recycling WW with Scaleban technology.

Figure 5.2 Solubility of Ca

2+

and Mg

2+

vs temperature and pH.

Figure 5.3 The galvanic principle on which Scaleban works.

Figure 5.4 Scaleban working process in a cooling tower circuit.

Figure 5.5 Principle of forward osmosis.

Figure 5.6 Forward osmosis plant.

Figure 5.7 Typical process flow diagram of an FO plant. KL, kilo liter; ML, ...

Figure 5.8 Activated glass media.

Figure 5.9 Activated glass media arrangement.

Figure 5.10 Activated glass media filter.

Figure 5.11 Schematic of vacuum distillation.

Figure 5.12 Vacuum distillation.

Figure 5.13 System configuration of solar detoxification process.

Figure 5.14 Sustainable WW treatment scheme inside a large complex.

Chapter 6

Figure 6.1 Power consumption range of various ZLD technologies.

Figure 6.2 Capital cost associated with various ZLD technologies.

Figure 6.3 Process flow diagram for ETP to meet standard discharge norms.

Figure 6.4 Process flow diagram for ETP to meet ZLD norms. PSF, pressure san...

Figure 6.5 Environmental feasibility of ZLD plant.

Figure 6.6 Economic feasibility of ZLD plant.

Figure 6.7 Operating cost and power consumption breakup in ZLD plant.

Guide

Cover Page

Series Page

Title Page

Copyright

Series Editor Foreword – Challenges in Water Management

Preface and Acknowledgments

List of Abbreviations

Table of Contents

Begin Reading

Index

WILEY END USER LICENSE AGREEMENT

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Challenges in Water Management Series

Editor:

Justin TaberhamPublications and Environment Consultant, London, UK

Titles in the series:

Water Harvesting for Groundwater Management: Issues, Perspectives, Scope, and ChallengesPartha Sarathi Datta2019ISBN: 978‐1‐119‐47190‐5

Smart Water Technologies and Techniques: Data Capture and Analysis for Sustainable Water ManagementDavid A. Lloyd Owen2018ISBN: 978‐1‐119‐07864‐7

Handbook of Knowledge Management for Sustainable Water SystemsMeir Russ2018ISBN: 978‐1‐119‐27163‐5

Industrial Water Resource Management: Challenges and Opportunities for Corporate Water StewardshipPradip K. Sengupta2017ISBN: 978‐1‐119‐27250‐2

Water Resources: A New Water ArchitectureAlexander Lane, Michael Norton, and Sandra Ryan2017ISBN: 978‐1‐118‐79390‐9

Urban Water SecurityRobert C. Brears2016ISBN: 978‐1‐119‐13172‐4

Wastewater Treatment Technologies

Design Considerations

Mritunjay Chaubey

Mumbai, India

This edition first published 2021© 2021 John Wiley & Sons Ltd

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Library of Congress Cataloging‐in‐Publication Data

Names: Chaubey, Mritunjay, author. Title: Wastewater treatment technologies : design considerations / Mritunjay Chaubey, Mumbai, India. Description: Hoboken : Wiley‐Blackwell, 2021. | Series: Challenges in water management series | Includes bibliographical references and index. Identifiers: LCCN 2020032111 (print) | LCCN 2020032112 (ebook) | ISBN 9781119765226 (hardback) | ISBN 9781119765240 (adobe pdf) | ISBN 9781119765257 (epub) Subjects: LCSH: Sewage–Purification. | Sewage disposal plants. | Water reuse. Classification: LCC TD745 .C37 2021 (print) | LCC TD745 (ebook) | DDC 628.3–dc23 LC record available at https://lccn.loc.gov/2020032111LC ebook record available at https://lccn.loc.gov/2020032112

Cover Design: WileyCover Image: Maximilian Stock Ltd./Getty Images

Series Editor Foreword – Challenges in Water Management

The World Bank in 2014 noted:

Water is one of the most basic human needs. With impacts on agriculture, education, energy, health, gender equity, and livelihood, water management underlies the most basic development challenges. Water is under unprecedented pressures as growing populations and economies demand more of it. Practically every development challenge of the 21st century – food security, managing rapid urbanization, energy security, environmental protection, adapting to climate change – requires urgent attention to water resources management.

Yet already, groundwater is being depleted faster than it is being replenished and worsening water quality degrades the environment and adds to costs. The pressures on water resources are expected to worsen because of climate change. There is ample evidence that climate change will increase hydrologic variability, resulting in extreme weather events such as droughts floods, and major storms. It will continue to have a profound impact on economies, health, lives, and livelihoods. The poorest people will suffer most.

It is clear there are numerous challenges in water management in the 21st century. In the 20th century, most elements of water management had their own distinct set of organizations, skill sets, preferred approaches, and professionals. The overlying issue of industrial pollution of water resources was managed from a “point source” perspective.

However, it has become accepted that water management has to be seen from a holistic viewpoint and managed in an integrated manner. Our current key challenges include:

The impact of climate change on water management, its many facets and challenges – extreme weather, developing resilience, storm‐water management, future development, and risks to infrastructure

Implementing river basin/watershed/catchment management in a way that is effective and deliverable

Water management and food and energy security

The policy, legislation, and regulatory framework that is required to rise to these challenges

Social aspects of water management – equitable use and allocation of water resources, the potential for “water wars,” stakeholder engagement, valuing water, and the ecosystems that depend upon it.

This series highlights cutting‐edge material in the global water management sector from a practitioner as well as an academic viewpoint. The issues covered in this series are of critical interest to advanced‐level undergraduates and Masters students as well as industry, investors, and the media.

Justin Taberham, CEnv

Series Editor

www.justintaberham.com

Preface and Acknowledgments

Globally, the practice of wastewater treatment before discharge does not seem to be good at this moment in time. As per the United Nations World Water Development Report 2017, on average, globally, over 80% of all wastewater is discharged without treatment. The discharge of untreated or inadequately treated wastewater into the environment results in the pollution of surface water, soil, and groundwater. As per the World Health Organization (WHO), water‐related diseases kill around 2.2 million people globally each year, mostly children in developing countries. We need to understand that wastewater is not merely a water management issue – it affects the environment and all living beings, and can have direct impacts on economies.

The establishment of UN Sustainable Development Goal 6 (Clean Water and Sanitation) aims to ensure availability and sustainable management of water and sanitation for all, reflecting the increased attention on water and wastewater treatment issues in the global political agenda. The author of this book is convinced that water reuse is one of the most efficient, cost‐effective, and ecofriendly ways to ensure water resilience. The author also believes that embedding sustainability into wastewater treatment is the best opportunity for industries to drive smarter innovation and efficient wastewater treatment. In order to develop sustainable wastewater treatment, we need to evaluate wastewater treatment systems in a broad sense. Economic aspects, treatment performance, carbon emissions, recycling, and social issues are important when evaluating the sustainability of a wastewater treatment system and selecting an appropriate system for a given condition. The modern concept of industrial wastewater treatment is moving away from conventional design. The trend is toward extreme modular design using smart and sustainable technology.

This book is intended as a reference book for all wastewater treatment professionals throughout the world. It may also be used as a textbook in the wastewater treatment training institutes and colleges and universities conducting graduate and postgraduate courses in the field of wastewater treatment and management. It will be equally useful for wastewater treatment plant operational personnel. This book covers a holistic view of the practical problems faced by the process industry and provides needs‐based multiple solutions to tackle the wastewater treatment and management issues. This book elaborates on selection of right technology and design criteria for different types of wastewater. This will enable engineering students and professionals to expand their horizon in the wastewater treatment and management field.

The contents of this book are well organized. The book elaborates the problems and issues of wastewater treatment and then provides solutions and suggests how to implement those solutions in a sustainable way. Chapter 1 covers the global perspective of wastewater treatment, in which topics like global best practices, embedding sustainability into wastewater treatment, sustainable sources for industrial water, deep sea discharge, environmental rule of law, the polluter pays principle, and wastewater treatment technology trends are discussed. Chapter 2 is fully devoted to providing an understanding of the wastewater characteristics of several industries. In this chapter the author has tabulated the wastewater characteristics of more than 30 industries based on his personal and practical experience with these industries. Chapter 3 provides an overview of all commercially available wastewater treatment technologies. Chapter 4 details design considerations and design methodology, which are well illustrated based on the author’s past 24 years of professional experience in wastewater treatment plant design. Chapter 5 covers the latest advances in sustainable wastewater treatment technologies. This chapter is purely based on the experience of the author of this book. The author has been involved in the piloting and customization of these technologies. Chapter 6 is devoted to zero liquid discharge technologies, offering an environmental and economic feasibility study. Chapter 7 covers wastewater treatment plant operational excellence. In this chapter, whether you are an experienced practitioner or an engineer who deals with the treatment of wastewater, you will find a myriad of practical advice and useful techniques that can immediately apply to solving problems in wastewater treatment. Throughout the book, attempts have been made to embed the theory in practical knowledge of wastewater technologies.

I extend my most sincere gratitude to my colleagues at Pentair, Shell, Unilever, and UPL for providing me with an environment to innovate and develop sustainable wastewater treatment technologies. I am also thankful to all my social media followers for encouraging me to write this book. The book could not have been completed without their motivation and support.

Last but not least, I would like to thank my family, especially Anubhav, Anushka, and Pummy, for providing moral support while writing this book.

Dr Mritunjay Chaubey

Ph.D. from Indian Institute of Technology Delhi

List of Abbreviations

ACF

activated carbon filter

AGF

activated glass media filter

AOP

advanced oxidation process

AOR

actual oxygen requirement

AOx

adsorbable organic halides

API

American plate interceptor

ASP

activated sludge process

ASU

activated sludge unit

ATFD

agitated thin film evaporator

BDD

boron‐doped diamond

BOD

biochemical oxygen demand

BP

belt press

BTEX

benzene, toluene, ethylbenzene, and xylene

BW

brackish water

CAGR

compound annual growth rate

CAPEX

capital expenditures

CAS

conventional activated sludge

CEB

chemically enhanced backwash

CETP

common effluent treatment plant

CIP

cleaning in place

COC

cycle of concentration

COD

chemical oxygen demand

conc.

concentrated

CWAO

catalytic wet air oxidation

DAF

dissolved air flotation

DI

deionized

DMF

dual media filter

DNB

denitrification/nitrification biotreater

DO

dissolved oxygen

EBT

eriochrome black T

EDTA

ethylene diamine tetra acetic acid

EO

electro‐oxidation

EPDM

ethylene propylene diene monomer

ETP

effluent treatment plant

F/M

food to microorganism (ratio)

FAS

ferrous ammonium sulfate

FFBR

fixed film biological reactor

FIC

flow indicator control

FMCG

fast moving consumer goods

FO

forward osmosis

FP

filter press

GAC

granular activated carbon

HAL

hybrid anerobic lagoon

HRSCC

high rate solid contact clarifier

HTDS

high total dissolved solids

HRT

hydraulic retention time

I&C

instrumentation and control

INDB

intermittent nitrification/denitrification biotreater

IWRM

integrated water resources management

LIC

level indicating control

LIT

level indicating transmitter

LSI

Langlier Saturation Index

LTDS

low total dissolved solids

MBBR

moving bed biofilm reactor

MBR

membrane bioreactor

MEE

multiple‐effect evaporator

MGF

multigrade filter

MLSS

mixed liquor suspended solids

MLVSS

mixed liquor volatile suspended solids

MMO

mixed metal oxide

MS

mild steel coated with epoxy paint

NIST

National Institute of Standards and Technology

NOM

natural organic matter

NTU

nephelometric turbidity units

O&G

oil and grease

OPEX

operating expenses

ORP

oxidation reduction potential

PABR

p

acked anerobic bed reactor

PLC

programmable logic controller

PM

preventive maintenance

ppm

parts per million

PSF

pressure sand filter

PVDF

polyvinylidene fluoride

RBC

rotating biological contractor

RCC

reinforced cement concrete

RO

reverse osmosis

SBR

sequencing batch reactor

SDG

Sustainable Development Goal

SND

simultaneous nitrification and denitrification

SOP

standard operating procedure

SRT

sludge retention time

SSVI

settleable sludge volume index

SVI

sludge volume index

TDS

total dissolved solids

TKN

total Kjeldahl nitrogen

TOC

total organic carbon

TPI

tilted plate interceptor

TSS

total suspended solids

UN

United Nations

UNEP

United Nations Environment Program

UASB

up‐flow anerobic sludge blanket

UF

ultrafiltration

US‐EPA

United States Environmental Protection Agency

UV

ultraviolet

VFD

variable frequency driver

VOC

volatile organic compounds

WAS

waste activated sludge

WHO

World Health Organization

WW

wastewater

WWTP

wastewater treatment plant

ZLD

zero liquid discharge

1Global Perspective of Wastewater Treatment

CHAPTER MENU

1.1 Global Wastewater Treatment Scenario

1.2 The UN Sustainable Development Agenda for Wastewater

1.3 Global Market Size

1.4 Global Best Practices

1.5 Embedding Sustainability into Wastewater Treatment

1.6 Sustainable Sources for Industrial Water

1.7 Deep Sea Discharge as an Alternative to Minimize Human and Environmental Health Risks

1.8 Environmental Rule of Law

1.9 Trends in Wastewater Treatment Technology

1.1 Global Wastewater Treatment Scenario

Natural water in contact with foreign matter during either industrial manufacturing processes or domestic use becomes polluted. Such polluted water is termed wastewater. The removal of excessively accumulated foreign matter from wastewater is known as treatment. As is well known, the rate at which we deplete and degrade our fresh aquatic resources poses a great threat to our future life‐support system. The rise in human population exploits more natural resources and this is met through the growth of industries, urbanization, deforestation, and intensive agricultural practices. Industries and urban sprawl discharge waste into rivers, the deforestation process itself aggravates sedimentation transport into streams, and the use of chemicals contaminates groundwater through percolation and rivers and lakes through surface run‐off.

All these sporadic degrading activities have led to gradual deterioration in the quality of surface and subsurface water. The loss of water quality is causing health hazards, death of human‐beings, death of aquatic life, crop failures, and loss of esthetics. Keeping in mind these alarming global problems and the importance of environmental and nature protection, the 1972 Stockholm Conference on the Human Environment was the first of its kind and jolted the world into an awareness of environmental issues. A tangible result of that conference was the setting up of the United Nations Environment Program (UNEP) to serve as the conscience of the UN in matters concerning the environment. Twenty years later came the next landmark – the Earth Summit in Rio de Janeiro in 1992 – which exceeded everybody's expectations in terms of the number of attendees and scope of topics discussed. The Summit's message was broadcast to the world: “that nothing less than a transformation of our attitudes and behavior would bring about the necessary changes.”

Figure 1.1 Global wastewater treatment scenarios.

Globally, the practice of wastewater treatment before discharge does not seem to be good. On average, high‐income countries treat about 70% of the municipal and industrial wastewater they generate [1]. That percentage drops to 38% in upper middle‐income countries and to 28% in lower middle‐income countries. In low‐income countries, only 8% of wastewater undergoes treatment of any kind. These estimates support the often‐cited approximation that, globally, over 80% of all wastewater is discharged without treatment. In high‐income countries, the motivation for advanced wastewater treatment is either to maintain environmental quality or to provide an alternative water source when coping with water scarcity. However, the release of untreated wastewater remains common practice, especially in developing countries, due to lack of infrastructure, technical and institutional capacity, and financing (see Figure 1.1).

The discharge of untreated or inadequately treated wastewater into the environment results in the pollution of surface water, soil, and groundwater. The effects of releasing untreated or inadequately treated wastewater can be classified with regard to three issues:

Adverse human health effects.

Negative environmental effects due to the degradation of water bodies and ecosystems.

Potential effects on economic activities: as the availability of freshwater is critical to sustain economic activities, poor water quality constitutes an additional obstacle to economic development.

According to the World Health Organization (WHO), water‐related diseases kill around 2.2 million people globally each year – mostly children in developing countries.

1.2 The UN Sustainable Development Agenda for Wastewater

In September 2015, approximately 193 nation members of the United Nations General Assembly unanimously adopted “Agenda 2030” with a total of 17 Sustainable Development Goals (SDGs) to end poverty, protect the planet, and ensure prosperity for all (see Figure 1.2).

Figure 1.2 UN Sustainable Development Goals.

The establishment of SDG 6 (Clean Water and Sanitation) is aimed at ensuring availability and sustainable management of water and sanitation for all, reflecting the increased attention on water and wastewater treatment issues in the global political agenda. Agenda 2030 lists rising inequalities, natural resource depletion, environmental degradation, and climate change as among the greatest challenges of our time. It recognizes that social development and economic prosperity depend on the sustainable management of freshwater resources and ecosystems and it highlights the integrated nature of SDGs.

SDG 6 includes eight global targets that are universally applicable and aspirational. SDG 6 covers the entire water cycle, including: provision of drinking water (target 6.1) and sanitation and hygiene services (6.2); improved water quality, wastewater treatment, and safe reuse (6.3); water‐use efficiency and scarcity (6.4); integrated water resources management (IWRM) including through transboundary cooperation (6.5); protecting and restoring water‐related ecosystems (6.6); international cooperation and capacity‐building (6.a); and participation in water and sanitation management (6.b).

SDG target 6.3 (to improve water quality, wastewater treatment, and safe reuse) focuses mainly on collecting, treating, and reusing wastewater from households and industry, reducing diffuse pollution and improving water quality. As per SDG 6 Synthesis Report 2018 on Water and Sanitation [2], ambient freshwater quality is at risk globally. Freshwater pollution is prevalent and increasing in many regions worldwide. Preliminary estimates of household wastewater flows from 79 mostly high‐ and high‐middle‐income countries show that 59% is safely treated. For these countries, it is further estimated that safe treatment levels of household wastewater flows with sewer connections and on‐site facilities are 76 and 18%, respectively.

The degree of industrial pollution is not known, as discharges are ineffectively observed and only from time to time calculated and aggregated at national level. Although some local and modern wastewater is treated nearby, hardly any information is accessible and amassed for national and territorial evaluations. Numerous nations come up short on the ability to gather and analyse the information required for a full appraisal. Reliable water quality monitoring is fundamental to the direct needs for ventures. It is also important for assessing the status of aquatic ecosystems and the need for protection and restoration.

Increasing political will to tackle pollution at its source and to treat wastewater will protect public health and the environment, mitigate the costly impact of pollution, and increase the availability of water resources. Wastewater is an undervalued source of water, energy, nutrients, and other recoverable by‐products. Recycling, reusing, and recovering what is normally seen as waste can alleviate water stress and provide many social, economic, and environmental benefits.

Managing wastewater by implementing global best practices of wastewater collection and treatment can support achievement of SGD target 6.3. Wastewater should be seen as a sustainable source of water, energy, nutrients, and other recoverable by‐products, rather than as a burden. Choosing the most appropriate type of wastewater treatment system that can provide the most co‐benefits is site specific, and countries need to build capacity to assess this. Reuse of water needs to take into account the whole river basin, as wastewater from one part of a basin may well be the source of supply for others downstream.

Managing wastewater and water quality also needs to include better knowledge of pollution sources. SDG reporting could support countries in aggregating wastewater subnational data and publicly reporting at the national level. This would include monitoring performance to ensure treatment plants are managed and maintained to deliver effluent suitable for safe disposal or use according to national standards, which may vary from country to country. Countries that do not have national standards and monitoring systems need to assess performance of on‐site and off‐site domestic wastewater treatment systems. Formalizing the informal sector through various policy instruments is needed to prevent excessive contamination. Incentives for the informal sector to be registered with the government could be accompanied by combined analysis of all wastewater sources and their relative contribution to health and environmental risks. This would enable countries to prioritize investments in pollution control that contribute most to achieving SDG target 6.3.

1.3 Global Market Size

The global market for water and wastewater technologies reached USD 64.4 billion in 2018 and should reach $83.0 billion by 2023, at a compound annual growth rate (CAGR) of 5.2% for the period 2018–2023 [3] (see Figure 1.3).

Figure 1.3 The global market size of water and wastewater technologies.

1.4 Global Best Practices

Treatment of wastewater has received steadily increasing attention across the world. During the manufacturing of industrial products, wastewater is generated at various stages which is very complex in nature and highly variable in quantity and quality. Unless we adopt a structured approach toward collection, segregation, and treatment, it will be difficult to achieve the desired results. Best practices in wastewater treatment include:

Reducing water consumption at source.

Maximizing recycling and reusing during production.

Promoting effluent identification, characterization, and segregation at source.

Deploying sustainable technology to treat wastewater.

Minimizing treated wastewater disposal.

Eliminating incineration of wastewater.

See Figure 1.4.

Figure 1.4 Best practices in wastewater treatment.

1.4.1 Effective Wastewater Treatment

Wastewater treatment is a complex process, and a properly operated wastewater treatment plant has many requirements. Below are six top considerations for effective wastewater treatment.

1.4.1.1 Discharge Standards

The first consideration is to understand the local discharge standards from the environmental authority. The authority may require that you submit a permit application or notice of intent that typically describes the sources, characteristics, and volumetric flow of your industrial wastewater discharge.

1.4.1.2 Wastewater Inlet Characteristics

We should understand the processes that produce waste streams and the wastewater characteristics of each stream. Review procedures for how products and reagents are combined to produce wastewater streams. Once we have sound knowledge of the characteristics and variability of the wastewater, we can design a treatment system and develop protocols to ensure continuous and compliant operation.

1.4.1.3 Wastewater Mass Balance

We should be familiar with the mass balance of how much water flows into a manufacturing plant and how many pollutants are in the wastewater. By conducting mass balances on all the constituents, a thorough understanding of the process can be obtained, leading to the optimal performance of the system. Flow rate is the most critical factor when calculating the capacity of a wastewater treatment system.

1.4.1.4 Wastewater Segregation

A structured approach toward wastewater treatment help us to manage complex industrial effluent. The best way to manage complex and variable industrial wastewater is through wastewater stream identification, characterization, and segregation (see Figure 1.5). The all‐incoming effluent stream should be identified and segregated into green, yellow, and red streams. The green stream may consist of all the wastewater stream having total dissolved solids (TDS) <5000 ppm and chemical oxygen demand (COD) <10 000 ppm. The yellow stream may consist of all the wastewater stream having TDS <100 000 ppm and COD <20 000 ppm. The red stream may consist of all the wastewater stream having TDS >100 000 ppm and COD >20 000 ppm. After stream identification and segregation, the green stream may be treated with biological treatment technologies such as an activated sludge process or a moving‐bed biological reactor; the yellow stream may be treated with forward osmosis (FO), Scaleban, or OH radical technology; and the red stream may be treated with multi‐effect evaporation technology or any other appropriate evaporation technology.

Figure 1.5 Wastewater stream segregation.

1.4.1.5 Sustainable Technology

We should use sustainable wastewater treatment technologies that consume less power and chemicals, generate less hazardous solid waste, and use minimum manpower. Use of sustainable wastewater treatment technology is the best opportunity for industries to drive smarter innovation and efficient wastewater treatment. Sustainable technology ensures a pollution‐free society, compliance with environmental norms, and creation of wealth from waste.

1.4.1.6 Standard Operating Procedures

Standard operating procedures (SOPs) of wastewater treatment plants must be documented and available to operators for reference. It is important for operators to know their daily, weekly, and monthly responsibilities. Operators are a key resource in the wastewater treatment plant. Operators are responsible for managing pumps, probes, and filtration equipment, general housekeeping, testing alarms, and any other tasks to keep a safe and orderly facility. If new technologies are added to the system, operators must be trained to operate these.

1.5 Embedding Sustainability into Wastewater Treatment

Embedding sustainability into wastewater treatment provides the best opportunity for industries to drive smarter innovation and efficient wastewater treatment. To analyze the full scope of embedding sustainability into wastewater treatment we can use a lifecycle cost analysis tool. To reach a final decision, the different indicators should be normalized and weighted to integrate them into a single final objective, which makes the search for a sustainable solution a multi‐objective optimization problem. Important objectives in selecting sustainable wastewater treatment technologies are as follows:

Minimize use of resources such as water, energy, chemicals, and space.

Minimize treatment costs.

Minimize production of harmful waste products.

Minimize use of manpower.

Maximize the treatment efficiency.

Maximize social‐cultural embedding through acceptance, participation, and stimulation of sustainable behavior.

Due to the complexity and the dynamic understanding of today's problems, there is a risk of introducing new problems when implementing technical solutions. To ensure that solutions have a positive overall impact on society, one needs to be clear about lifecycle cost assessment.

In order to develop sustainable wastewater treatment, we need to evaluate wastewater treatment systems in a broad sense. Economic aspects, treatment performance, carbon emissions, recycling, and social issues are important when evaluating the sustainability of a wastewater treatment system and selecting an appropriate system for a given condition. Selection of a wastewater treatment scheme requires a multidisciplinary approach in which engineers and technocrats discuss with economists, biologists, health officials, and the public.

1.5.1 Optimizing the Operating Cost of Wastewater Treatment Plants

Under sustainability, optimizing the operating cost and reducing the environmental footprint of a wastewater treatment plant are very important. Here, one case study of the wastewater treatment cost of a chemical industry is presented to understand the actual cost associated with wastewater treatment inside a large chemical manufacturing plant (see Table 1.1). Based on actual data received from the wastewater treatment plants of various chemical industries, the author of this book summarizes the average cost of wastewater treatment within chemical and agrochemical manufacturing plants. This operating cost is for a biological wastewater treatment plant to treat effluent having an inlet COD of 5000–8000 ppm and treated outlet COD <250 ppm (see Figure 1.6).

Table 1.1 Average cost of wastewater treatment plants in chemical industries.

Cost monitoring parameters

Average cost (USD/m

3

)

Power cost

1

Chemical cost

1.5

Sludge disposal cost

1

Treated effluent disposal cost

0.5

Manpower cost

1

Total cost

5

Figure 1.6 Operating cost composition of chemical industry wastewater treatment plants.

With the use of sustainable wastewater treatment technologies, we may further reduce power consumption, chemical consumption, sludge generation, and involvement of manpower in wastewater treatment plants.

1.5.2 New Sustainable Wastewater Treatment Technologies

Use of sustainable wastewater treatment technologies is a key factor in embedding sustainability into wastewater treatment. Sustainable wastewater treatment systems depend on a number of factors including minimal use of resources such as water, energy, chemicals, and space; minimum treatment costs; minimum production of harmful waste products; minimum use of manpower; maximum treatment efficiency; and maximum social‐cultural embedding through acceptance, participation, and stimulation of sustainable behavior. Some of these new sustainable wastewater treatment technologies are now discussed.

1.5.2.1 Forward Osmosis

FO is a membrane‐based wastewater treatment technology utilizing drawdown solution to treat high TDS (<100 000 ppm) and moderate COD (<20 000 ppm). FO is a natural process and an integral part of the survival of flora and fauna on this planet. In general, the FO process is governed by differences in osmotic pressure, and the direction of water diffusion takes place from a lower concentration (the feed side) to a higher concentration (the draw side). The driving force for this separation is an osmotic pressure gradient which is generated by a draw solution of high concentration to induce a net flow of water through the membrane into the draw solution, thus effectively separating the feed water from its solute. As osmosis is a natural phenomenon, it significantly requires less energy compared to the conventional reverse osmosis (RO) process. FO technology can be used for highly saline waters which are impossible to treat through conventional wastewater treatment processes (see Figure 5.6).

1.5.2.2 Scaleban

Scaleban is a unique and patented technology that helps industries achieve water conservation and zero liquid discharge (ZLD) by integrating process effluent and RO reject water having high TDS with existing cooling towers in place of freshwater. Scaleban uses a cooling tower as a natural evaporator without affecting the plant's performance in relation to hard water scaling, corrosion, and bio‐fouling in the cooling tower circuit. With application of the Scaleban system, cooling towers can be operated at higher TDS; hence effluent treatment plant (ETP)‐treated water/effluent can be used as the cooling tower makeup water, thus reducing raw water consumption without requiring any extra energy input for its operation (see Figure 1.7).

1.5.2.2.1 Advantages

Reduced abstracted water demand in the cooling tower by utilizing treated wastewater.

Much less capital and operational expenditure compared to conventional technologies to achieve ZLD.

Figure 1.7 Scaleban equipment installed in a cooling tower.

Figure 1.8 Volute press equipment.

Can handle higher COD and TDS water efficiently.

Quick installation and commissioning without occupying any extra footprint.

No major infrastructural changes required for installation.

1.5.2.3 Volute Press

A volute press is a multidisc sludge dewatering press that removes water and moisture from sludge on a continuous basis. It consists of two types of rings: a fixed ring and a moving ring. A screw tightens the rings and pressurizes the sludge. Gaps between the rings and the screw are designed to gradually get narrower toward the direction of the sludge cake outlet, and the inner pressure of the discs increases due to the volume compression effect, thickening and dewatering the sludge (see Figure 1.8).

1.5.2.3.1 Advantages

Continuous and clean operation without regular manual intervention.

Produces high‐quality filtrate with much less total suspended solids (TSS) (i.e. high solid recovery).

Extremely low power consumption – reduces power consumption up to 95%.

Low noise and odor generation.

Low wash water consumption.

1.5.2.4 Moving Bed Biofilm Reactor

The moving bed biofilm reactor (MBBR) system is an advanced activated sludge process whereby biological sludge is immobilized on plastic carriers having a very large internal surface area. The aeration system keeps the carriers with activated sludge in motion, thus providing a larger and wider contact between microorganisms and wastewater for efficient wastewater treatment (see Figures 3.13 and 1.9).

Figure 1.9 An MBBR plant.

1.5.2.4.1 Advantages

Compact system with smaller area footprint compared to conventional activated sludge process.

Higher food to microorganisms ration (F/M) loading with reduced retention time.

Less biological sludge generation and no biomass recycling required.

Faster installation and commissioning.

Higher treatment efficiency.

1.5.2.5 Dissolved Air Floatation

Dissolved air floatation (DAF) technology is a modern version of conventional primary effluent treatment, where suspended solids are removed by dissolving atmospheric air in wastewater under pressure and then releasing the air in a flotation tank basin. The released air forms tiny bubbles, causing the suspended matter to float on the surface, and in turn can be removed from wastewater using a skimming device (see Figure 3.6).

1.5.2.5.1 Advantages

Very compact system which reduces the area footprint significantly.

Quick installation and commissioning.

Higher suspended solids removal efficiency with ability to handle bulking floating solids.

Lower capital expenditures (CAPEX) and operating expenses (OPEX).

1.6 Sustainable Sources for Industrial Water

Industrial water scarcity is one of the major impacts on businesses worldwide, leading to higher operating costs and difficulty in staying competitive. For industries, day by day controlling costs is difficult and this worsens when the price of water increases exponentially to the point where profit margins shrink precariously. This causes industries to regard water access as a competitive advantage and to adopt sustainable sources for industrial water. In the following sections, the various sources of industrial water along with approximate costs are summarized.

1.6.1 ZLD Water

ZLD water is generated inside industrial manufacturing plants by adopting ZLD treatment methods. Industry uses a number of technologies and various stages of wastewater treatment to get ZLD water. The approximate cost of ZLD water is in the range of USD 10–17/m3 water produced. ZLD water not only is costly but also generates huge amounts of carbon and hazardous solid waste. Due to the higher cost and higher environmental footprint, ZLD water is not a sustainable source for industrial water.

1.6.2 Desalinated Water

Desalinated water is generated by desalination of seawater by adopting RO treatment methods. Industry uses various kinds of membrane to produce desalinated water. The approximate cost of desalinated water is in the range of USD 0.7–1/m3 water produced. In coastal areas, desalinated water seems to be a sustainable source for industrial water.

1.6.3 Sewage Water

Sewage water is generated from municipal sewage treatment plants by treating domestic sewage. This treated domestic sewage will be further treated by industries as per requirement . Sewage generation is increasing rapidly on a global basis, and in the absence of adequate infrastructure for collection and treatment, the already depleting freshwater reservoirs are being polluted. In the present global water scarcity, sewage wastewater is the new black gold on the planet Earth. Various decentralized sewage treatment facilities are being set up for recycling and reuse of wastewater. Advanced treatment technologies are being adopted for sewage treatment. Globally, there is increasing focus on adding treatment capacity, improving collection efficiency, and automating operations for wastewater. New public–private partnership models and long‐term operations and maintenance contracts are being introduced to benefit wastewater treatment plants. These measures will improve wastewater management and generate social, environmental, and economic benefits, and are essential to achieving Agenda 2030 SDGs.

The approximate cost of sewage water is in the range of USD 0.4–0.5/m3 water produced. In areas where a sufficient amount of treated municipal sewage is available for industrial use, sewage water seems to be a sustainable and economical source for industrial water. By using sewage water in industrial manufacturing, we can also prevent water pollution.

1.6.4 Rainwater

During rainy seasons we get huge amounts of rainwater. We need to collect, store, filter, and reuse rainwater for manufacturing processes. Industrial rainwater is becoming increasingly important for commercial entities to reduce their environmental impact across their operations. Industrial rainwater harvesting is an extremely cost‐effective method of achieving this goal, with the added benefit of reducing water consumption and bills. Industrial rainwater harvesting systems are easy to install and maintain, whilst providing cost‐effective savings on water consumption; resulting in reduced water bills. The approximate cost of rainwater harvesting is less than USD 0.15/m3 water produced. In areas where a sufficient amount of rainfall is available, rainwater is thus the better and sustainable choice of all available water options (see Figure 1.10).

Figure 1.10 Alternative sources for industrial water.

1.7 Deep Sea Discharge as an Alternative to Minimize Human and Environmental Health Risks

Deep sea discharge of treated wastewater can be an effective, reliable, and economical solution to wastewater disposal that has minimal environmental impacts and avoids water pollution problems in coastal regions. The marine environment has a high capacity for dispersion and decay of organic matter. This capacity lies in the available energy in the marine environment due to the action of ocean currents on wastewater dispersion, the availability of dissolved oxygen, and due to it being a hostile environment to the survival of microorganisms.

The National Research Council of the US National Academy [4] specifically recommended against a “one size fits all” approach to arbitrary specification of treatment levels, stating:

Coastal wastewater and stormwater management strategies should be tailored to the characteristics, values, and uses of the particular receiving environment based on a determination of what combination of control measures can effectively achieve water and sediment quality objectives.

Sydney's deepwater ocean outfalls have delivered high‐quality outcomes for the environment and the community [5]. Beaches and harbors are cleaner and the marine environment is healthy.

Since the deepwater ocean outfalls opened in 2004,

Swimming conditions have significantly improved.

Beach grease has been eliminated.

There has been no detectable negative effect on marine ecology or sediments.

Effluent discharged has consistently been shown to be non‐toxic at its diluted state.

Figure 1.11 A deep sea discharge wastewater disposal system.

A typical deep sea discharge system for treated wastewater disposal is shown in Figure 1.11. It usually consists of a wastewater collection pipeline, combined wastewater treatment plant, and discharge structure – the deep sea discharge outfall.

Deep sea discharge outfalls release treated wastewater 2–10 km off the coast, where it mixes with seawater with the help of diffusers. The primary treated effluent is conveyed through tunnels under the ocean floor and is released through a series of diffusers. These diffusers release the effluent in fine jet streams, so it mixes immediately with seawater and disperses into the strong sea current. Because it is less dense than the salty seawater, the effluent moves upward and outward into the current as it disperses into an area called the mixing zone. At the same time, the current continues to move it away from the coastline. Natural processes eventually break down the effluent components, which are by now very highly diluted.

1.7.1 Mixing Zone

The mixing zone is very important for the dilution of wastewater in the sea. In the United States, the Environmental Protection Agency (US‐EPA) regulations for toxics [6] define a mixing zone as: