Waste Water Treatment

Ozone use for Wastewater Treatment has many uses and a wide variety of applications. Common ozone wastewater treatment applications:

- Wastewater disinfection

- Color removal from water

- Sludge reduction

- Odor removal from wastewater

- Degradation of toxic substances

Ozone can be cost effectively implemented for these applications in municipal wastewater streams, and industrial applications. Many times ozone is a more cost effective solution that requires less space, and fewer chemicals that traditional treatment methods.

Wastewater Disinfection:

Ozone used for wastewater disinfection has the potential to lower/eliminate chemical additions into water providing for a green solution and save you money. Ozone is a powerful oxidant that will provide excellent disinfection to any water stream. The oxidation potential of ozone is greater than that of all other chemicals used for wastewater disinfection.

Ozone ws initially utilized for disinfection of drinking water starting back in 1906. (history of ozone use) The use of ozone for wastewater disinfection did not gain attention until the early 1970's. By 1984 there were 43 operational municipal wastewater treatment plants utilizing ozone for disinfection in the United States alone. However, the implementation of ozone in large scale municipal plants stagnated after about 1985. This was due mostly to the low cost of chlorine, and the lack of regulation on chlorine residuals in water.

Ozone use for wastewater disinfection has again gained attention in recent years. Ozone is again becoming cost effective and necessary for three main reasons:

1. Chemical costs have increased dramatically in recent years. Handling costs, storage costs, and cost of the raw chemical have created a for a high cost for traditional chlorine and even chlorine dioxide. This has allowed ozone to become a more cost effective solution.

2. Regulations are getting tougher to meet with traditional chemicals. Regulations on e.coli, and coliform bacteria are becoming lower and lower in most every state in the nation, and even worldwide. Combine this with lower discharge limits on residual chlorine. This requires higher chemical usage for chlorine removal from water after disinfection. These lower discharge limits for bacteria, and chlorine create an atmosphere where ozone is very cost competitive, and may be the only viable option for some treatment facilities.

3. Micro-pollutants, or Endocrine Disrupting Chemicals (EDC's) are becoming a major concern in rivers and lakes where wastewater is discharged. Ozone or Advanced Oxidiation Processes (AOP) are proving to be the only viable option for removal of these contaminates in wastewater.

Add to these primary factors that ozone is a green technology that may reduce overall energy consumption and chemical residual in water and ozone looks very attractive for many plants. Both municipal wastewater treatment plants, and industrial plants, such as meat packing plants have been investing in ozone systems for wastewater disinfection in recent years.

Color Removal From Wastewater:

Wastewater color removal with ozone

Wastewater may have high levels of discoloration from industrial processes such as dye manufacturing. Ozone has been proven to be an excellent oxidant to remove color from any water source cost effectively and simply. In applications where wastewater simply has a high level of discoloration that is causing negative issues at the municipal wastewater treatment plant, rivers, or lakes, ozone is a great choice for color removal.

Sludge Reduction Using Ozone:

Ozone can be used to lower overall sludge production from wastewater treatment plants. Ozone can also be used to treat sludge that is produced to improve dewaterablility, and break down sludge to minimize overall sludge production.

One of the greatest costs of operating a wastewater treatment plant is handling and dispelling of the generated sludge. By implementing ozone to reduce overall sludge from the plant cost savings can be realized.

Many applications and methods of ozone implementation into wastewater treatment have proven successful for sludge reduction. For information about your specific plant and how ozone could lower your costs contact our ozone application engineers.

Odor Removal From Wastewater:

Odor removal using ozone is used worldwide for many commercial and industrial applications. Ozone use for odor removal is most likely the most common use of ozone worldwide. Ozone is commonly used in homes and businesses to remove odors from smoke, pets, and mold. The same oxidation process that allows ozone to be so efficient in these applications can also be implemented in wastewater treatment and handling.

Odors are naturally generated from wastewater treatment processes, and handling processes. Ozone can be implemented in many of these processes to reduce or completely eliminate odors.

Wastewater lift stations can implement ozone in the head-space of the lift station by forcing air mixed with ozone into this headspace. When the water level in the pit of the liftstation increases and air is forced from the head-space this air will be treated with ozone and ensure all escaping air will be odor free.

Wastewater processes implementing aeration can implement ozone in the aeration process. As this air has low solubility into the water much of the ozone will escape into the head-space. The air escaping the process will not be free of odor.

There are many creative methods to implement ozone into wastewater treatment processes. As urban areas encroach on sewer plants, and additional sewer plants are constructed near urban development, odor is of increasing concern. Please call our application engineers for details on how ozone can be used to treat odor in your application.

Degradation of Toxic Substances:

Ozone can oxidize any substance that is not in it's complete oxidized state. Therefore most toxic substances found in water can be oxidized by ozone for safe and cost effective removal without dangerous chemical by-products.

Common toxic substances oxidized by ozone in water:

- Phenol

- Benzene

- Cyanide

- Naphthalene

- Olefins

- Pesticides

- Herbicides

- Ammonia

- Pentachlorophenol

- Ethane

- Atrazine

- MTBE

- Toluene

Click here for more compounds ozone will oxidize, along with reaction kinetics.

This is just a short list of common contaminated ozone is used to oxidize from water. We can provide specific information and references for each of these, along with other information as required. Please contact our office for more details.

Micropollutants, or Endocrine Disrupting Chemicals (EDC's) removal with ozone is gaining the most attention of all ozone and wastewater treatment applications. Ozone has proven to be the most effective oxidant at removing Micropollutant and EDC's from watewater either alone or used in conjunction with AOP processes.

The Lingo:

- Micropollutants: substances that are found in relatively low concentrations that are difficult or impossible to remove with conventional treatment technologies.

- Endocrine Disrupting Compounds (EDC’s): substances which impact the hormone functions of animals and humans

- Naturally or industrially produced

- Disrupt growth, development or reproduction

- Influence the behavior of humans and animals

- Endocrine System: consists of glands and hormones that regulates the development, growth, reproduction and the behavior of animals as well as humans.

- Personal Care Products: fragrances, sunscreens, cleaning products, etc

- EDC’s, pharmaceuticals and personal care products are groups of emerging contaminants

Build-up of EDC's in wastewater is of primary concern for plants that discharge into lakes, or rivers where water may move slow and allow levels to compound over time. In some locations this same body of water is used as a supply for drinking water plants. The Great Lakes region in the United States is a great example of a body of water that is used for wastewater discharge and drinking water supply that could have a build-up of EDC's in the water over time.

Ozone has been tested and proven effective in removing many EDC's in wastwater treatment systems. The following is a short list of EDC's ozone has been proven effective for:

- Testosterone

- Androstenedione

- Progesterone

- Estradiol

- Estriol

- Estrone

- Ethynylestradiol

- Carbamazepine

- Bezafibrate

- Diclofenac

- Ibuprofen

- Sulfamethoxazole

For a complete list, details on each EDC, or information about how ozone could be implemented as a pilot test, or full scale system contact our application engineers today.

View the Questionnaire for Waste Water Treatment so we can help design your Ozone System

White Paper Research Documents:

Below is a list of technical documents and papers on the use of ozone in aquaculture for your review. Click on text links below to open the PDF documents.

Dissolved Ozone Destruction using Ultraviolet Irradiation in a Recirculating Salmonid Culture System

Authors: Steven T. Summerfelt, Mark J. Sharrer, Jennifer Holls, Lauren E. Gleason, Scott R. Summerfelt

Abstract

The Warburg Wastewater Treatment Plant (WWTP) in North Rhine-Westphalia, Germany, faced challenges with micropollutants—such as pharmaceuticals and personal care products—present in its effluent. To address this, the plant implemented an advanced treatment process combining ozonation and the AnoxKaldnes™ eXeno™ Moving Bed Biofilm Reactor (MBBR). Ozonation effectively removed over 80% of 14 targeted pharmaceuticals and pesticides at a dosage of 0.7 mgO₃/mgDOC. However, this process generated ozonation transformation products (OTPs) with unknown properties. The subsequent eXeno™ MBBR treatment achieved a 95% reduction of these OTPs, ensuring minimal release of potentially toxic by-products into surface waters. The success of this integrated approach led to its adoption at another German facility in Rheda-Wiedenbrück.

Read the full study here.

U.S. Environmental Protection Agency (EPA) Ozone Disinfection Fact Sheet

Authors: EPA

Abstract

The document titled "Wastewater Technology Fact Sheet: Ozone Disinfection," published by the U.S. Environmental Protection Agency (EPA) in September 1999, provides an overview of using ozone as a disinfectant in wastewater treatment. It explains that disinfection is crucial for inactivating or destroying pathogenic organisms to prevent the spread of waterborne diseases. Ozone, a strong oxidant and virucide, is produced onsite by exposing oxygen to a high-voltage electrical discharge. The document describes the mechanisms by which ozone disinfects—such as direct oxidation of cell walls and damage to nucleic acids—and outlines the components of an ozone disinfection system, including feed-gas preparation, ozone generation, contacting, and destruction. Additionally, it emphasizes that wastewater must be adequately treated before disinfection to ensure effectiveness.

Read the full study here.

Ozone Enhanced Biofiltration for Municipal Wastewater Use

Authors: xylem

Abstract

With climate change, population growth, and increasing water scarcity, the demand for sustainable water resource management is higher than ever. Recently, the combination of ozonation and biologically active filtration (BAF) has gained attention due to its synergistic effects, offering enhanced performance while reducing operational costs, media replacement frequency, and ozone dosage. To evaluate the key operating parameters of this combined process and guide future system design, a comprehensive pilot study was planned and launched in January 2014. The study, conducted at the Hammarby Wastewater Treatment Plant, includes an ozone contactor and biologically active filters to assess the efficiency and feasibility of this approach in municipal wastewater treatment.

Read the full study here.

The Multiple Benefits of Ozone in Municipal Wastewater Treatment and Recycling

Authors: James R. Jackson

Abstract

Global climate change has created regional drought conditions, making water scarcity a grim reality that threatens the economic vitality of both local and regional communities. California’s $ 45 billion agricultural sector, for example, may leave over a half-million acres fallow this year due to severe cuts in the water supply. This has caused high unemployment in the California farm communities and potentially higher produce prices at supermarkets across North America. A growing number of utilities located in drought regions have installed advanced treatment processes at their wastewater treatment facilities for indirect reuse as an alternate water source for agricultural and domestic use or for seawater intrusion protection of ground water. This presentation reviews three case histories where ozone is used in conjunction with other treatment processes to bring wastewater effluent into compliance with water quality standards for agricultural application or the replenishment of a regional drinking water source. Description of the advance treatment processes featuring ozone application method by high efficiency side stream venturi injection (SVI) and pipeline flash reactor (PFR) bulk flow mixing and lesson’s learned when utilizing ozone on secondary wastewater will be review.

Read the full study here.

The Multiple Benefits of Ozone in Municipal Wastewater Treatment and Recycling

Authors: James R. Jackson

Abstract

The effects of endocrine substances and persistent micropollutants on our ecosystem often demand an extensive treatment solution. Ozone is one of the most powerful commercially available oxidants and is commonly used for municipal water and wastewater treatment. Pollutants, colored substances, odors and microorganisms are directly destroyed by oxidation without creating harmful chlorinated byproducts or significant residues. By decomposing to oxygen as it reacts, ozone provides a cost-effective and sustainable alternative to oxidation involving chlorine, absorption or other separation processes. By combining ozone with ultraviolet (UV) or peroxide, advanced oxidation processes (AOPs) reduce even the most persistent substances. AOPs help to render other previously nondegradable water pollutants harmless. These benefits are driving the use of ozone in applications beyond water and wastewater treatment, including reuse, sludge removal, process water and cooling water.

Read the full study here.

Experience with Ozone Disinfection at the Little Falls Water Treatment Plant

Authors: Proceedings of the Water Environment Federation

Abstract

Passaic Valley Water Commission (PVWC) is a publicly owned water purveyor centrally located in northeastern New Jersey. The Commission is owned by the cities of Paterson, Passaic and Clifton and serves 21 wholesale customers in Passaic, Bergen, Essex, Hudson and Morris Counties. PVWC supplies water to an equivalent population of 800,000 people with an average demand of approximately 88 million gallons per day (MGD). The demand is met through the production of finished water at the Little Falls Water Treatment Plant (LFWTP), owned by PVWC, supplemented by finished water provided from the North Jersey District Water Supply Commission. PVWC recently completed an upgrade of the LFWTP that included the installation of an intermediate ozonation process for primary disinfection. This paper presents an overview of the upgraded water treatment process with an emphasis on the ozonation process and improvements to water quality.

Read the full study here.

Control of Dangerous Substances in Discharges and Microbiological Abatement: European Framework and a Case Study of an Ozone Disinfection System

Authors: M. Ostoich, F. Serena, L. Falletti, A. Fantoni

Abstract

Directive 2000/60/EC requires the achievement of a 'good chemical status' for surface water within pre-established dates. Disinfection is needed to achieve compulsory final microbial limit values (in Italy for wastewater discharges the parameter Escherichia coli - EC - is imposed by law with a maximum limit value of 5,000 cfu/100 mL). Liquid waste and disinfection by-products must be considered when designing appropriate monitoring of dangerous substances; the specific classes of substances must be investigated according to the typology of received wastewaters and liquid wastes (where applicable) and specific analytical techniques, with Limit of Detection (LOD) lower than the limit values, must be applied; the difficulties faced by national and regional environmental control Agencies is that these techniques have to be applied during ordinary activity and not only for research purposes. The study aims to present the control of dangerous substances, as a screening view, in wastewater treatment plant (WWTP) discharges in the province of Venice (Northern Italy) for the period 2007-2010 based on available data from institutional controls. In addition, the wastewater disinfection process with ozone applied to a medium size WWTP (45,000 Population Equivalents) is presented as a case study, with a view to assessing the microbiological abatement efficacy and the presence of dangerous substances. Discharge quality of the WWTPs in the province of Venice presented mean values that were higher than the LOD, but only for certain metals. For the Paese plant, zinc and chloroform were the only micro-pollutants detected with a higher level than the LOD. From microbiological data in the period 2006-2011 the disinfection abatement efficiency for Paese was, in most cases above 99% for EC, faecal coliform (FC), faecal streptococci (FS) while efficiency was slightly lower for total coliform (TC); however, the proposed criterion aimed at respecting 99.99% abatement was not completely satisfied. Therefore, despite the high organic and industrial load of the considered plant and the need to find an alternative system for chlorine, as chlorine disinfection has been banned in the Veneto region since December 2012, ozone efficiency is not completely satisfactory and other systems such as peracetic or performic acids and UV systems must be considered.

Read the full study here.

Ozone Application in Recirculating Aquaculture System

Authors: Alex Augusto Goncalves, Graham A. Gagnon

Abstract

A vast number of persistent organic pollutants have been found in wastewater effluent, surface water, and drinking water around the world. This indicates their ineffective removal from water and wastewater using conventional treatment technologies. In addition to classical persistent organics such as organochlorine insecticides, solvents, and polychlorinated biphenyls, a growing number of emerging pollutants of both synthetic and natural origins have been identified as major environmental pollutants in recent years. A variety of advanced and conventional treatment options have been suggested for the removal and/or destruction of these persistent organics in water and wastewater, such as chemical oxidation, activated carbon adsorption, and membrane filtration. Of these options, chemical oxidation using ozone, alone or in combination with additional physical/chemical agents (i.e., advanced oxidation), has been proved a highly effective treatment process for a wide spectrum of emerging aqueous organic pollutants, including pesticides, pharmaceuticals, personal care products, surfactants, microbial toxins, and natural fatty acids. In this paper, we discuss the emerging organic pollutants of concern in the aquatic environment and focus on the issues associated with their removal using ozonation and advanced oxidation processes.

Read the full study here.

Direct Application of Ozone in Aquaculture Systems

Authors: Adam Powell, Jacob W.S. Scolding

Abstract

Ozone is a strong oxidant that can be used in the potabilization of surface or ground water as well as in wastewater treatment to remove microorganisms, inorganic ions and organic pollutants. The oldest use of ozone is as a biocide in drinking water potabilization. The integral ozone exposure required for a given degree of disinfection can be calculated from the deactivation kinetic constant of the microorganism. Ozone removes iron, manganese and arsenic from water by oxidation to an insoluble form that is further separated by filtration. Both processes require ozone in molecular form, but the removal of organic pollutants that are refractory to other treatments can be possible only by exploiting the indirect radical reactions that take place during ozonation. Ozone decomposes in water, especially when hydrogen peroxide is present, to yield the hydroxyl radical, the strongest oxidizer available in water treatment. Models for the ozonation process are required to adjust the ozone dosing to the desired degree of removal of a given pollutant or an aggregate measure of pollution. Mineralization, defined as the removal of organic carbon, has been accomplished in wastewaters from urban and domestic treatment plants. The results show that the logarithmic decrease of TOC as a function of the integral ozone exposure usually presents two zones with different kinetic parameters.A. Rodríguez et al. Among advanced oxidation processes, a promising alternative currently under development is the use of ozone in combination with solid catalysts. The mechanism of catalytic ozonation is not clear, but in the case of metal oxides, the adsorption of ozone or organic compounds on Lewis acid sites is only possible near the point of zero charge of the surface. Activated carbon seems to behave as an initiator of ozone decomposition, a role that may also occur with other types of catalysts. Some results on the mineralization of water with the drugs naproxen (non-steroidal anti-inflammatory) and carbamazepine (anticonvulsant) are presented using titanium dioxide as catalyst.

Read the full study here.

Chemistry of Ozone in Water and Wastewater Treatment

Authors: von Sonntag, Clemens von Gunten

Abstract

Even though ozone has been applied for a long time for disinfection and oxidation in water treatment, there is lack of critical information related to transformation of organic compounds. This has become more important in recent years, because there is considerable concern about the formation of potentially harmful degradation products as well as oxidation products from the reaction with the matrix components. In recent years, a wealth of information on the products that are formed has accumulated, and substantial progress in understanding mechanistic details of ozone reactions in aqueous solution has been made. Based on the latter, this may allow us to predict the products of as yet not studied systems and assist in evaluating toxic potentials in case certain classes are known to show such effects. Keeping this in mind, Chemistry of Ozone in Water and Wastewater Treatment: From Basic Principles to Applications discusses mechanistic details of ozone reactions as much as they are known to date and applies them to the large body of studies on micropollutant degradation (such as pharmaceuticals and endocrine disruptors) that is already available. Extensively quoting the literature and updating the available compilation of ozone rate constants gives the reader a text at hand on which his research can be based. Moreover, those that are responsible for planning or operation of ozonation steps in drinking water and wastewater treatment plants will find salient information in a compact form that otherwise is quite disperse. A critical compilation of rate constants for the various classes of compounds is given in each chapter, including all the recent publications. This is a very useful source of information for researchers and practitioners who need kinetic information on emerging contaminants. Furthermore, each chapter contains a large selection of examples of reaction mechanisms for the transformation of micropollutants such as pharmaceuticals, pesticides, fuel additives, solvents, taste and odor compounds, cyanotoxins.

Read the full study here.

Ozone-Based Processes Applied to Municipal Secondary Effluents

Authors: Bruno Domenjoud, Carolina Tatari, Santiago Esplugas, Sylvie Baig

Abstract

This study analyzes the performances of 2 methods of oxidation based on ozone, namely ozonation and ozone combined with hydrogen peroxide (O₃/H₂O₂), on two biotreated municipal wastewater effluents. The main parameters monitored to evaluate the effectiveness of the processes were Chemical Oxygen Demand (COD), Dissolved Organic Carbon (DOC) and Biochemical Oxygen Demand (BOD₅). Ozonation and O₃/H₂O₂ treatment removed 44% and 48%, respectively, of the COD, after 90 min, of the secondary effluent of Calafell wastewater treatment plant (Spain). On the secondary effluent from the Grasse wastewater treatment plant (France), these same treatments (O₃; O₃/H₂O₂) achieved, respectively, a degradation of 52% and 100% of the COD after 60 min. The transferred ozone dose (TOD) during Calafell and Grasse effluents' ozonation were 122 mg·L⁻¹ and 77 mg·L⁻¹ after 90 min, respectively. A low removal of DOC was monitored during both O₃ or O₃/H₂O₂ treatments applied to Calafell wastewater, respectively 12% and 14%. Better DOC reductions were obtained on the water of Grasse treated with O₃ or O₃/H₂O₂, respectively, 48% and 60%. In addition, ammonia nitrogen was oxidized to nitrate nitrogen thus giving rise to an over ozone consumption. And finally, both processes proceeded with an increase of pH values. These results highlight the strong dependency of O₃ or O₃/H₂O₂ treatment effectiveness in terms of dissolved organic matter (DOM) removal and ozone consumption on wastewater composition (organic and inorganic substances).

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Oxidation of Emerging Contaminants during Pilot-Scale Ozonation of Secondary Treated Municipal Effluent

Authors: Saileshkumar Singh, Rejesh Seth, Shahram Tabe, Paul Yang

Abstract

The transformation of 41 target emerging contaminants in secondary treated municipal wastewater effluent in Canada was examined at pilot-scale, at transferred ozone doses of 2.8 mg/L (0.46 O₃/mg DOC) and 4.4 mg/L (0.72 mg O₃/mg DOC). In general, transformation efficiencies of CECs either increased or were retained at the higher ozone dose. The higher ozone dose of 0.72 mg O₃/mg DOC (Z_spec = 0.6 mg O₃/mg DOC) was sufficient to transform 21 of the 31 detected CECs by over 80% as well as achieving the disinfection target of < 200 MPN E. coli per 100 mL.

Read the full study here.

Ozone Treatment of Secondary Effluent at U.S. Municipal Wastewater Treatment Plants

Authors: Michael A. Oneby, Charles O. Bromley, James H. Borchardt, David S. Harrison

Abstract

Ozone is a strong oxidant used to treat a variety of constituents in potable water, wastewater, water reuse, and industrial water treatment applications. Ozone is effective at oxidizing a wide range of organic and inorganic compounds and disinfection. Well-known in potable water treatment, with about 400 US installations and 3,000 world-wide, ozone has limited application at wastewater treatments, with less than 10 operating facilities in the US. The ability of ozone to significantly reduce low level concentrations of trace organic compounds, including endocrine disrupting chemicals (EDCs), pharmaceuticals and personal care products (PPCPs), and other emerging contaminants have increased interest in applying ozone in potable water and wastewater treatment. Treating at the point source discharge rather than the water supply intake may be more effective. A recent American Water Works Research Foundation (AwwaRF) report indicated high removals of many EDCs and PPCPs at typical disinfection doses. Several wastewater utilities have installed or are in the process of installing ozone to treat secondary effluent. These utilities are using ozone in a variety of ways: as a primary disinfectant, for treatment of microconstituents, and in combination with other processes (e.g. membranes and UV) to produce high-quality water for indirect potable reuse (IPR). The different applications, treatment goals and basis of process selection are compared and contrasted. Secondary benefits of ozone treatment of secondary effluent, including the use of off-gas in biological treatment is also discussed.

Read the full study here.

Disinfection of Primary Municipal Wastewater Effluents Using Continuous UV and Ozone Treatment

Authors: Michael A. Oneby, Charles O. Bromley, James H. Borchardt, David S. Harrison

Abstract

UV radiation and ozonation were investigated as disinfection alternatives for the wastewater treatment plant. The inactivation of total and fecal coliforms using ozone and ultraviolet radiation as separate treatments was evaluated. Different ozone concentrations (3 to 40 mg O₃/L) were applied and UV fluencies ranging from 8.5 to 12 mJ/cm² at different pH values (from 5 to 9) were tested. Best results were obtained for ozone doses near 20 mg/min with removals of 72% and 78% of fecal and total coliforms, respectively. The ozone also was capable of oxidizing organic matter in the effluent measured as COD (the highest removal obtained was 36% for 20 mg O₃/min). Maximum bacterial resistance was observed at pH 7 in both cases. The UV light offered a high bacterial inactivation (over 80%) and the lowest bacterial inactivation was observed at pH 7. Finally, we obtained the electric energy per order (E_EO, kWh/m³/order), defined as the electric energy (kW-h) required to degrade a contaminant by one order of magnitude in a unit volume of contaminated water, being noteworthy that E_EO values for the UV process resulted were lower than those determined for the process with ozone in all the water flow tested.

Read the full study here.

Ozonation of Municipal Wastewater Effluents

Authors: Panagiota Paraskeva, Nigel J. D. Graham

Abstract

The increasing use of ozone in the treatment of municipal wastewater eﬀuents has been stimulated by the need to achieve higher efﬂuent quality and greater compliance with physicochemical and microbiological quality standards before discharge. These standards are applied when the efﬂuent may pose a risk to the public through direct contact and where the efﬂuent is used for agricultural purposes or water reclamation. Although various alternative technologies exist for upgrading wastewater efﬂuents, ozone treatment may be the most appropriate approach in particular cases. This review summarizes the current status of the use of ozone for treating municipal efﬂuents with respect to disinfection efﬁciency, its effect on the treatability of the efﬂuent and on aggregate efﬂuent parameters, the potential for the formation of ozonation byproducts, and its effect on the toxicity and mutagenicity of the efﬂuent. The importance of treatment conditions (e.g., contact time) is also reviewed.

Read the full study here.

Water and Wastewater Treatment through Ozone-based Technologies

Authors: Satyendra Tripathi, Touseef Hussain

Abstract

Water is a very precious resource and abundant compound without which a human may not be able to live for more that a few days on earth. Water has numerous significant functions in our body. Living organisms such as humans, animals, and plants are largely composed of water. It is usually known as a universal solvent. It is mainly used in homes, agriculture, and industry. The most important causes which are responsible for water pollution as population growth, speedy industrialization, urbanization, apply science, and technology as well as current farming practices. There are several levels such as primary, secondary, and tertiary levels of wastewater treatment. Primary and secondary levels of wastewater are used in most of the municipal wastewater treatment and several apply tertiary treatments also. Screens and settling tanks are used for removal of most of the solids in primary treatment. Although bacteria use for consuming the remaining pollutants present in the secondary level of wastewater treatment. Whereas tertiary or advanced treatment applies for removal of dissolved materials for instance color, organic chemicals, and metals as well as nutrients like nitrogen and phosphorus. Some other conventional treatment techniques for wastewater like adsorption activated sludge, chemical coagulation are applied for removal of pollutants, though there are several limitations, particularly high cost of operation. This chapter is focused on ozone-based technologies for water and wastewater treatment. Ozone is a strong oxidant which uses for potabilization of ground or surface water and in treatment of wastewater for eliminating inorganic ions, organic pollutants and microbes. The cost of the ozonation is usually higher than that of other disinfection techniques. Ozone based treatment of wastewater have multiple applications. It is currently used as an oxidant of inorganic and organic molecules, a coagulant aid, a disinfectant, taste and odor remover, controlling of algae and other microbes. The ozone treatment technology for disinfection of bacteria, protozoa, and viruses are very effective.

Read the full study here.

Ozone-based Processes

Authors: Keisuke Ikehata, Yuan Li

Abstract

Ozone is one of the most powerful oxidants that have been widely used in water and wastewater treatment. Here, the applications of ozone-based advanced oxidation processes (AOPs) in municipal and industrial wastewater treatment are described. The basics of ozone reactions in water and wastewater are first introduced, including ozone and hydroxyl radical reaction pathways, types of AOPs, and byproduct formation. Subsequently, a historical background of ozone wastewater treatment, as well as recent research works on different wastewater treatment using various ozone-based AOPs, such as ozone/hydrogen peroxide, ozone/UV, ozone/ultrasound, and ozone/titanium dioxide photocatalysis, are reviewed. A brief history of ozone wastewater treatment in the United States, followed by the current and planned ozone-based advanced wastewater treatment projects, are also provided in this chapter.

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Ozone Dose Dependent Formation and Removal of Ozonation Products of Pharmaceuticals in Pilot and Full-Scale Municipal Wastewater Treatment Plants

Authors: Suman Kharel, Michael Stapf, Ulf Miehe, Maja Ekblad, Michael Cimbritz

Abstract

The removal of micropollutants from municipal wastewater is challenged by the number of compounds with diverse physico-chemical properties. Ozonation is increasingly used to remove micropollutants from wastewater. However, ozonation does not necessarily result in complete mineralization of the organic micropollutants but rather transforms them into new compounds which could be persistent or have adverse environmental effects. To explore ozone dose dependency of the formation and successive removal of ozonation products, two pilot-scale and one full-scale ozonation plants were operated subsequent to a conventional activated sludge treatment. The results from these trials indicated that the concentrations of several N-oxides, such as Erythromycin N-oxide, Venlafaxine N-oxide and Tramadol N-oxide, increased up to an ozone dose of 0.56–0.61 mg O₃/mg DOC while they decreased at elevated doses of 0.7–1.0 mg O₃/mg DOC. Similar results were also obtained for two transformation products of Diclofenac (Diclofenac 2,5-quinone imine and 1-(2,6-dichlorophenyl)indolin-2,3-dione) and one transformation product of Carbamazepine (1-(2-benzoic acid)-(1H,3H)-quinazoline-2,4-dione), where the highest concentrations appeared around 0.27–0.31 mg O₃/mg DOC. The formation maximum of a given compound occurred at a specific ozone dose that is characteristic for each compound, but seemed to be independent of the wastewater used for the experiments at the two pilots and the full-scale plant.

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