Waste Water Treatment and Reuse

Waste Water Treatment and Reuse ?

Wastewater treatment and reuse is a critical component of sustainable water management, especially in a world facing increasing water scarcity. Here’s a breakdown of key aspects:

What is Wastewater Treatment and Reuse?

Wastewater Treatment:
- This is the process of removing contaminants from wastewater, which can originate from households (sewage), industries, or agriculture.
- The goal is to produce an effluent (treated wastewater) that can be safely discharged back into the environment or reused.
- Treatment involves various physical, chemical, and biological processes to remove pollutants like solids, organic matter, and pathogens.
Wastewater Reuse (Water Recycling/Reclamation):
- This involves taking treated wastewater and using it for beneficial purposes.
- It’s a way to supplement traditional water supplies and reduce pressure on freshwater resources.
- Reuse applications vary widely, depending on the treatment level and intended use.

Key Applications of Wastewater Reuse:

Agricultural Irrigation:
- A major use, especially in arid and semi-arid regions.
Landscape Irrigation:
- For parks, golf courses, and other green spaces.
Industrial Processes:
- Cooling water, process water, etc.
Municipal Uses:
- Toilet flushing, street cleaning, etc.
Groundwater Recharge:
- Replenishing aquifers.
Potable Reuse:
- Treating wastewater to drinking water standards (advanced treatment required).
Environmental Restoration:
- Enhancing wetlands, and other aquatic environments.

Benefits of Wastewater Treatment and Reuse:

Water Conservation:
- Reduces reliance on freshwater sources.
Environmental Protection:
- Minimizes pollution of rivers, lakes, and oceans.
Increased Water Security:
- Provides a reliable alternative water supply.
Economic Benefits:
- Can reduce water supply costs.

Important Considerations:

Treatment Standards:
- The level of treatment required depends on the intended reuse.
- Strict regulations are essential to protect public health and the environment.
Public Perception:
- Public acceptance is crucial for the success of reuse projects.
Infrastructure:
- Dedicated infrastructure is needed for collecting, treating, and distributing reclaimed water.

Wastewater treatment and reuse is becoming increasingly important as the world grapples with water scarcity and climate change.

What is Waste Water Treatment and Reuse ?

Wastewater treatment and reuse is a process that addresses the growing global concern of water scarcity. It involves:

Wastewater Treatment:
- This is the process of removing pollutants from wastewater, which comes from various sources like homes, industries, and agriculture.
- The goal is to purify the water so it’s safe to release back into the environment or to use again.
- This process utilizes physical, chemical, and biological methods to eliminate contaminants such as solids, organic matter, and harmful microorganisms.
Wastewater Reuse:
- This refers to the practice of using treated wastewater for beneficial purposes.
- It’s a sustainable way to supplement existing water supplies and reduce the strain on freshwater sources.
- The applications of reused wastewater vary depending on the level of treatment, and can include:
  - Agricultural irrigation
  - Landscape watering
  - Industrial processes
  - Municipal uses (like toilet flushing)
  - Replenishing groundwater
  - In some cases, even producing drinking water (potable reuse)

In essence, wastewater treatment and reuse is a crucial strategy for:

Conserving water resources.
Protecting the environment.
Enhancing water security.

I hope this information is helpful.

Who is required Waste Water Treatment and Reuse ?

Wastewater treatment and reuse is essential for a wide range of entities, and its importance is growing due to increasing water scarcity. Here’s a breakdown of who requires it:

1. Municipalities and Urban Areas:

Cities and towns:
- They generate large volumes of domestic wastewater (sewage) that must be treated to protect public health and the environment.
- Wastewater reuse can supplement their water supplies for non-potable uses like landscape irrigation and toilet flushing.
Residential complexes and communities:
- Apartment buildings and large residential areas are increasingly required to have on-site wastewater treatment systems.

2. Industries:

Manufacturing plants:
- Many industries produce wastewater containing various pollutants.
- They need to treat this wastewater to comply with environmental regulations before discharge.
- Wastewater reuse can reduce their reliance on freshwater for processes like cooling and cleaning.
Power plants:
- These facilities use large amounts of water for cooling, and wastewater treatment and reuse can significantly reduce their water consumption.
Food processing plants:
- These plants generate wastewater with high organic content, requiring effective treatment.

3. Agriculture:

Farms:
- Agricultural runoff can contain pollutants like fertilizers and pesticides.
- Wastewater treatment and reuse can provide a valuable source of irrigation water, especially in arid regions.
- Animal farming operations produce large amounts of waste that must be treated.

4. Commercial Entities:

Hospitals and hotels:
- These businesses generate significant amounts of wastewater and are increasingly focusing on sustainable water management.
Large commercial buildings:
- These buildings are starting to implement onsite water reuse systems.

Key Drivers for Wastewater Treatment and Reuse:

Environmental regulations: Governments are increasingly enforcing stricter regulations on wastewater discharge.
Water scarcity: Many regions are facing water shortages, making wastewater reuse a vital strategy.
Sustainability: Businesses and communities are adopting sustainable practices to reduce their environmental impact.

In essence, anyone who generates wastewater has a responsibility to treat it, and many have a strong incentive to reuse it.

When is required Waste Water Treatment and Reuse ?

Wastewater treatment and reuse becomes necessary in a variety of situations, driven by environmental concerns, water scarcity, and regulatory requirements. Here’s a breakdown of when it’s typically required:

Situations Requiring Wastewater Treatment:

Environmental Protection:
- Whenever wastewater is discharged into natural water bodies (rivers, lakes, oceans), treatment is essential to prevent pollution.
- Untreated wastewater can introduce harmful pollutants, damaging ecosystems and endangering aquatic life.
Public Health:
- Domestic wastewater (sewage) contains pathogens that can cause serious illnesses.
- Treatment is crucial to eliminate these pathogens and protect public health.
Regulatory Compliance:
- Governments at various levels establish regulations that mandate wastewater treatment.
- Industries and municipalities must comply with these regulations to avoid penalties.

Situations Favoring Wastewater Reuse:

Water Scarcity:
- In regions with limited freshwater resources, wastewater reuse provides a valuable alternative water supply.
- This is particularly important in arid and semi-arid areas.
Sustainable Water Management:
- Wastewater reuse promotes sustainable water use by reducing reliance on freshwater sources.
- It helps conserve precious water resources for future generations.
Economic Benefits:
- In some cases, wastewater reuse can reduce water supply costs for industries and municipalities.
- It can also create new economic opportunities in the water treatment and reuse sector.
Agricultural Needs:
- Where there is a high demand for irrigation water, and when treated properly, waste water can provide a valuable source of that water.

In summary:

Wastewater treatment is almost always required before discharge into the environment.
Wastewater reuse is increasingly required in areas facing water scarcity and where sustainable water management is a priority.

Essentially, the need for wastewater treatment and reuse is becoming more critical as global water demands increase and environmental concerns grow.

COURTESY : Down To Earth

Where is required Waste Water Treatment and Reuse ?

Wastewater treatment and reuse is becoming increasingly necessary in a variety of locations worldwide, particularly in areas facing specific challenges. Here’s a breakdown of where it’s most crucial:

1. Arid and Semi-Arid Regions:

These areas experience chronic water scarcity, making wastewater reuse a vital strategy to supplement limited freshwater resources.
Examples include:
- The Middle East
- Parts of Africa
- The Southwestern United States
- Australia

2. Densely Populated Urban Areas:

Cities generate large volumes of wastewater, and reuse can help alleviate pressure on strained water supplies.
Urban centers worldwide are increasingly implementing wastewater reuse programs.

3. Agricultural Regions:

Agriculture consumes a significant portion of freshwater resources.
Wastewater reuse can provide a reliable source of irrigation water, especially in areas with intensive farming practices.

4. Industrial Zones:

Industries require large amounts of water for various processes.
Wastewater reuse can reduce industrial water consumption and minimize environmental impact.

5. Coastal Areas:

Coastal regions are vulnerable to saltwater intrusion, which can contaminate freshwater aquifers.
Wastewater reuse can help replenish groundwater supplies and prevent saltwater intrusion.

Key Factors Driving the Need:

Climate Change:
- Increased droughts and unpredictable rainfall patterns are exacerbating water scarcity.
Population Growth:
- A growing global population is increasing the demand for water resources.
Environmental Regulations:
- Stricter regulations on wastewater discharge are driving the need for improved treatment and reuse practices.

In essence, wastewater treatment and reuse is essential wherever there is a need to conserve water, protect the environment, or ensure a reliable water supply.

How is required Waste Water Treatment and Reuse ?

The “how” of wastewater treatment and reuse involves a series of processes designed to remove contaminants and make the water safe for its intended purpose. Here’s a general overview:

1. Wastewater Treatment:

This typically involves a multi-stage process:

Preliminary Treatment:
- This stage removes large debris like rags, sticks, and grit through screening and grit removal.
- This protects downstream equipment from damage.
Primary Treatment:
- Here, wastewater flows into sedimentation tanks, where heavier solids settle to the bottom (sludge) and lighter materials float to the surface (scum).
- These materials are then removed.
Secondary Treatment:
- This stage focuses on removing dissolved organic matter.
- Biological processes are commonly used, where microorganisms consume the organic pollutants.
- The activated sludge process is a common example.
Tertiary Treatment (Advanced Treatment):
- This stage removes remaining pollutants, such as nutrients (nitrogen and phosphorus), pathogens, and trace contaminants.
- Processes like filtration, disinfection (using chlorine, UV light, or ozone), and membrane filtration may be used.

2. Wastewater Reuse:

Once the wastewater has been treated to the required standards, it can be reused. The “how” of reuse depends on the intended application:

Agricultural Irrigation:
- Treated wastewater is distributed through irrigation systems, such as sprinklers or drip irrigation.
- Careful monitoring of water quality is essential to protect crops and soil.
Landscape Irrigation:
- Similar to agricultural irrigation, treated water is used to irrigate parks, golf courses, and other green spaces.
Industrial Reuse:
- Treated wastewater can be used for cooling, process water, or other industrial applications.
- The level of treatment required depends on the specific industrial process.
Municipal Reuse:
- Treated water can be used for non-potable purposes, such as toilet flushing, street cleaning, and fire fighting.
- Dedicated distribution systems are often required.
Potable Reuse:
- This involves advanced treatment processes to produce drinking water.
- It’s a complex process with stringent quality control measures.
Groundwater Recharge:
- Treated water is introduced into aquifers to replenish groundwater supplies. This can be done through injection wells or infiltration basins.

Key Considerations:

Treatment Standards: The level of treatment must match the intended reuse.
Monitoring and Control: Continuous monitoring of water quality is essential to ensure safety.
Infrastructure: Adequate infrastructure is needed for collection, treatment, and distribution.

In essence, “how” wastewater treatment and reuse is required, is through a system of progressive purification, and then a distribution system that matches the quality of the water, to the required use.

Case study is Waste Water Treatment and Reuse ?

It’s very useful to look at real-world examples of wastewater treatment and reuse. Here are a few case study areas, with some key points:

1. Orange County, California (Groundwater Replenishment System):

This is a leading example of potable reuse.
Advanced treatment processes, including microfiltration, reverse osmosis, and ultraviolet light with hydrogen peroxide, are used to purify wastewater to drinking water standards.
The treated water is then injected into groundwater aquifers, supplementing the region’s water supply.
This project is widely recognized for its high standards and public acceptance.

2. Singapore (NEWater):

Singapore, a water-scarce island nation, has implemented NEWater, a program that produces high-quality reclaimed water.
NEWater undergoes advanced treatment and is used for industrial purposes and to augment reservoirs.
This has significantly enhanced Singapore’s water security.

3. The Textile Industry:

The textile industry is a large water user, and also a large producer of heavily polluted wastewater.
There are many case studies showing how advanced filtration systems, and ozonation are used to treat the very difficult waste water from this industry.
These systems are allowing the factories to greatly reduce their water consumption.

Key Themes in These Case Studies:

Advanced Treatment Technologies:
- These projects often employ sophisticated technologies to achieve high levels of purification.
Water Scarcity as a Driver:
- Many successful wastewater reuse projects are located in regions facing water shortages.
Public Acceptance:
- Public education and outreach are crucial for gaining support for reuse projects.
Environmental Benefits:
- Wastewater reuse helps conserve freshwater resources and reduce pollution.

Where to Find More Case Studies:

U.S. Environmental Protection Agency (EPA):
- The EPA provides resources and case studies on water reuse.
World Health Organization (WHO):
- The WHO publishes guidelines and case studies on safe wastewater reuse.
Water Research Foundation:
- This organization conducts research and publishes reports on water and wastewater treatment.
Search engine searches using terms like “Industrial waste water reuse case study” will bring up many very specific industry based examples.

COURTESY :
Imemflo Filtration Pvt. Ltd.

White paper on Waste Water Treatment and Reuse ?

It’s excellent that you’re looking into white papers on wastewater treatment and reuse. These documents often provide in-depth analyses and valuable insights. Here’s what I’ve found, with a focus on key themes and sources:

Key Themes in Wastewater Treatment and Reuse White Papers:

Resource Recovery:
- Many modern approaches view wastewater as a resource, not just a waste product. White papers often explore technologies for recovering valuable components like nutrients, energy (biogas), and, of course, water itself.
Sustainable Water Management:
- A central theme is the role of wastewater reuse in achieving water security and reducing reliance on freshwater sources. This is particularly relevant in regions facing water scarcity.
Technological Advancements:
- White papers highlight the latest technologies for advanced wastewater treatment, including membrane filtration, advanced oxidation processes, and real-time monitoring systems.
Policy and Governance:
- Effective policies and regulations are crucial for promoting safe and sustainable wastewater reuse. White papers may offer recommendations for policymakers.
Public Health and Environmental Protection:
- Ensuring the safety of reused wastewater is paramount. White papers address the need for rigorous treatment standards and monitoring to protect public health and the environment.

Where to Find Valuable White Papers:

State of Green:
- They publish documents such as “Unlocking the potential of wastewater” that compiles insights and tangible solutions from across the water value chain on how to use wastewater as a resource while protecting people and ecosystems. This contains information from many leading Danish water sector experts.
- This source focuses on cutting-edge technologies, innovative policy frameworks, and successful case studies.
Council on Energy, Environment and Water (CEEW):
- CEEW provides in depth analysis of the reuse of treated wastewater in India, including market potential and pointers for strengthening governance. This is very useful for information regarding developing nations.
Research Institutions and Organizations:
- Organizations like the Water Research Foundation and academic institutions often publish white papers and reports on wastewater treatment and reuse.
- publications from MDPI, provide peer reviewed scientific papers on the subject.
Government Agencies:
- Agencies like the U.S. Environmental Protection Agency (EPA) and similar organizations in other countries provide valuable resources and publications.
NITI Aayog:
- This organization produces papers such as “Reuse of Treated Wastewater in Urban/Peri-Urban Agriculture in India” This paper provides information regarding the reuse of wastewater in agriculture, and the challenges that are faced.

When searching for white papers, I recommend using specific keywords, such as:

“Advanced wastewater treatment white paper”
“Potable water reuse white paper”
“Industrial wastewater reuse case studies”
“Wastewater treatment policy white paper”

I hope this helps you in your research.

Industrial application of Waste Water Treatment and Reuse ?

Industrial wastewater treatment and reuse is a critical practice for sustainable manufacturing and resource management. Here’s a breakdown of its key applications:

Core Industrial Applications:

Cooling Towers and HVAC Systems:
- Treated wastewater can serve as a cost-effective and sustainable cooling agent.
- This reduces freshwater intake and minimizes energy consumption.
- Proper treatment is essential to prevent microbiological growth, scaling, and corrosion.
Industrial Processes and Manufacturing:
- Many industrial processes require water for cleaning, processing, and other operations.
- Reusing treated wastewater reduces freshwater demand, wastewater discharge, and operational costs.
- Water quality must be carefully monitored to avoid adverse effects on product quality.
Energy Production:
- Wastewater can be used for:
  - Cooling in power plants.
  - Generating steam for turbines.
  - Producing biofuels.
- This reduces energy inputs for water heating, transportation, and treatment.

Benefits of Industrial Wastewater Reuse:

Reduced Water Demand and Costs:
- Decreases reliance on freshwater, especially in water-scarce regions.
- Lowers water and wastewater treatment expenses.
Environmental Sustainability:
- Minimizes water pollution and conserves freshwater resources.
- Enhances corporate social responsibility.
Regulatory Compliance:
- Helps industries meet increasingly stringent environmental regulations.
Increased Water Security:
- Provides a reliable alternative water source.

Key Considerations:

“Fit-for-Purpose” Treatment:
- Wastewater should be treated to the quality required for its specific reuse application.
Monitoring and Control:
- Continuous monitoring of water quality is crucial to ensure safety and prevent process disruptions.
Regulatory Compliance:
- Industries must adhere to local and national regulations regarding wastewater reuse.

In essence, industrial wastewater treatment and reuse is a multifaceted approach that offers significant environmental and economic benefits.

Research and development of Waste Water Treatment and Reuse ?

Research and development (R&D) in wastewater treatment and reuse is a dynamic field, driven by the increasing need for sustainable water management. Here’s an overview of key R&D areas:

1. Advanced Treatment Technologies:

Membrane Technologies:
- R&D focuses on improving membrane performance (e.g., fouling resistance, energy efficiency) for microfiltration, ultrafiltration, nanofiltration, and reverse osmosis.
- This includes developing new membrane materials and configurations.
Advanced Oxidation Processes (AOPs):
- AOPs, such as ozonation, UV irradiation, and Fenton reactions, are being investigated for the removal of recalcitrant pollutants (e.g., pharmaceuticals, endocrine disruptors).
- Research aims to optimize AOPs for energy efficiency and cost-effectiveness.
Biological Treatment:
- Research explores innovative biological processes, such as membrane bioreactors (MBRs) and anaerobic digestion, for enhanced nutrient removal and energy recovery.
- Studies also focus on understanding and optimizing microbial communities in wastewater treatment systems.
Nature-Based Solutions:
- Constructed wetlands and other nature-based systems are being researched for their potential to provide cost-effective and environmentally friendly wastewater treatment.

2. Resource Recovery:

Nutrient Recovery:
- R&D focuses on developing technologies to recover valuable nutrients, such as nitrogen and phosphorus, from wastewater.
- This includes processes for producing fertilizers and other valuable products.
Energy Recovery:
- Research explores methods for recovering energy from wastewater, such as biogas production from anaerobic digestion.
- Studies also investigate the potential for using wastewater as a heat source.
Water Reclamation:
- Development of systems that can process waste water to potable, or near potable standards.

3. Monitoring and Control:

Real-time Monitoring:
- R&D focuses on developing sensors and monitoring systems for real-time assessment of wastewater quality.
- This enables better control of treatment processes and ensures the safety of reused water.
Data Analytics and Modeling:
- Research explores the use of data analytics and modeling to optimize wastewater treatment and reuse systems.
- This includes developing predictive models for water quality and treatment performance.

4. Addressing Emerging Contaminants:

Microplastics:
- Research investigates the occurrence and removal of microplastics in wastewater.
Pharmaceuticals and Personal Care Products (PPCPs):
- Studies focus on developing advanced treatment technologies for the removal of PPCPs from wastewater.

Key Drivers of R&D:

Increasing Water Scarcity:
- The need for alternative water sources is driving the development of wastewater reuse technologies.
Stricter Environmental Regulations:
- Regulations are pushing for higher standards of wastewater treatment and discharge.
Technological Advancements:
- Advances in materials science, biotechnology, and data analytics are enabling the development of more effective and efficient wastewater treatment and reuse systems.

Essentially, R&D in this field is working to make waste water treatment more effective, more efficient, and more sustainable.

COURTESY : VentilAQUA

References

^ “wastewater treatment | Process, History, Importance, Systems, & Technologies”. Encyclopedia Britannica. October 29, 2020. Retrieved 2020-11-04.
^ Jump up to:^a ^b ^c ^d Metcalf & Eddy Wastewater Engineering: Treatment and Reuse (4th ed.). New York: McGraw-Hill. 2003. ISBN 0-07-112250-8.
^ Takman, Maria; Svahn, Ola; Paul, Catherine; Cimbritz, Michael; Blomqvist, Stefan; Struckmann Poulsen, Jan; Lund Nielsen, Jeppe; Davidsson, Åsa (2023-10-15). “Assessing the potential of a membrane bioreactor and granular activated carbon process for wastewater reuse – A full-scale WWTP operated over one year in Scania, Sweden”. Science of the Total Environment. 895: 165185. Bibcode:2023ScTEn.89565185T. doi:10.1016/j.scitotenv.2023.165185. ISSN 0048-9697. PMID 37385512. S2CID 259296091.
^ Tchobanoglous, George; Burton, Franklin L.; Stensel, H. David (2003). Metcalf & Eddy Wastewater Engineering: Treatment and Reuse (4th ed.). McGraw-Hill. ISBN 978-0-07-112250-4.
^ Khopkar, S.M. (2004). Environmental Pollution Monitoring And Control. New Delhi: New Age International. p. 299. ISBN 978-81-224-1507-0.
^ Jump up to:^a ^b Takman, Maria; Svahn, Ola; Paul, Catherine; Cimbritz, Michael; Blomqvist, Stefan; Struckmann Poulsen, Jan; Lund Nielsen, Jeppe; Davidsson, Åsa (2023-10-15). “Assessing the potential of a membrane bioreactor and granular activated carbon process for wastewater reuse – A full-scale WWTP operated over one year in Scania, Sweden”. Science of the Total Environment. 895: 165185. Bibcode:2023ScTEn.89565185T. doi:10.1016/j.scitotenv.2023.165185. ISSN 0048-9697. PMID 37385512. S2CID 259296091.
^ Von Sperling, M. (2007). “Wastewater Characteristics, Treatment and Disposal”. Water Intelligence Online. 6. doi:10.2166/9781780402086. ISSN 1476-1777. Text was copied from this source, which is available under a Creative Commons Attribution 4.0 International License
^ Jump up to:^a ^b Jones, Edward R.; van Vliet, Michelle T. H.; Qadir, Manzoor; Bierkens, Marc F. P. (2021). “Country-level and gridded estimates of wastewater production, collection, treatment and reuse”. Earth System Science Data. 13 (2): 237–254. Bibcode:2021ESSD…13..237J. doi:10.5194/essd-13-237-2021. ISSN 1866-3508.
^ Tchobanoglous G, Burton FL, Stensel HD (2003). Metcalf & Eddy Wastewater Engineering: treatment and reuse (4th ed.). McGraw-Hill Book Company. ISBN 0-07-041878-0.
^ George Tchobanoglous; Franklin L. Burton; H. David Stensel (2003). “Chapter 3: Analysis and Selection of Wastewater Flowrates and Constituent Loadings”. Metcalf & Eddy Wastewater engineering: treatment and reuse (4th ed.). Boston: McGraw-Hill. ISBN 0-07-041878-0. OCLC 48053912.
^ Von Sperling, M. (2007). “Wastewater Characteristics, Treatment and Disposal”. Water Intelligence Online. 6. doi:10.2166/9781780402086. ISSN 1476-1777. Text was copied from this source, which is available under a Creative Commons Attribution 4.0 International License
^ “Pollution Prevention Case Studies”. Washington, D.C.: U.S. Environmental Protection Agency (EPA). 2021-08-11.
^ Reed, Sherwood C. (1988). Natural systems for waste management and treatment. E. Joe Middlebrooks, Ronald W. Crites. New York: McGraw-Hill. ISBN 0-07-051521-2. OCLC 16087827.
^ “Landfills Effluent Guidelines”. EPA. 2018-03-16.
^ Primer for Municipal Waste water Treatment Systems (Report). Washington, DC: US Environmental Protection Agency (EPA). 2004. EPA 832-R-04-001..
^ Ajay Kumar Mishra Smart Materials for Waste Water Applications, Wiley-Scrivener 2016 ISBN 111904118X https://onlinelibrary.wiley.com/doi/book/10.1002/9781119041214
^ Gupta, Ashok; Yan, Denis, eds. (2016-01-01), “Chapter 16 – Gravity Separation”, Mineral Processing Design and Operations (Second Edition), Amsterdam: Elsevier, pp. 563–628, doi:10.1016/B978-0-444-63589-1.00016-2, ISBN 978-0-444-63589-1, retrieved 2020-11-30
^ Jump up to:^a ^b ^c Weber, Walter J. (1972). Physicochemical processes for water quality control. New York: Wiley-Interscience. ISBN 0-471-92435-0. OCLC 389818.
^ BERGENDAHL, JOHN. “Applications of Advanced Oxidation for Wastewater Treatment” (PDF). Dept. Of Civil & Environmental Engineering, WPI. Archived (PDF) from the original on 2017-08-29.
^ “Water Disinfection – an overview | ScienceDirect Topics”. www.sciencedirect.com. Retrieved 2023-03-02.
^ Wastewater engineering : treatment and reuse. George Tchobanoglous, Franklin L. Burton, H. David Stensel, Metcalf & Eddy (4th ed.). Boston: McGraw-Hill. 2003. ISBN 0-07-041878-0. OCLC 48053912.
^ Deng, Yang; Zhao, Renzun (2015-09-01). “Advanced Oxidation Processes (AOPs) in Wastewater Treatment”. Current Pollution Reports. 1 (3): 167–176. Bibcode:2015CPolR…1..167D. doi:10.1007/s40726-015-0015-z. ISSN 2198-6592.