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Evaluates the effect of bioaugmentation on the activated sludge treatment of food wastewaters including those containing potato, starch, sugar and milk. Parameters of study include live liquid microorganisms, dosage, aeration time and wastewater strength. Concludes that bioaugmentation with addition of live liquid micro‐organisms improves total organic carbon (TOC) removal efficiency and reduces sludge production. Aerobic bioaugmentation is effective in TOC removal from potato, sugar and milk wastewater but not effective in the case of starch wastewater.

The purpose of this paper is to investigate the efficacy of bacterial exopolysaccharides (Eps) in reactive black 5 (RB5) textile dye wastewater bioremediation.

The Eps were produced by bacteria isolated from cotton gin trash soils collected from different cotton-growing regions in Kenya for comparison purposes. A broth medium reconstituted using molasses was assessed for its capacity to produce the Eps. RB5 textile dye wastewater was optimized for dye removal under different temperatures, times and molasses concentrations. Dye removal was studied by Lovibond-Day Light Comparator, UV–Vis spectrophotometer and FTIR.

It was found that cotton gin trash soils contained Eps-producing bacteria. Three of the Eps studied were found to have the capacity to remove at least 80% of the dye from the wastewater.

This research did not assess the efficacy of the RB5 dye removal from the wastewater by mixtures of the Eps.

Bioremediation of textile dye wastewater with Eps produced by bacteria cultured from cotton gin trash soil is significant because it will offer an effective and cleaner alternative to the chemical coagulants.

Alternative treatment of textile wastewater with the Eps would result in safer water being released into the water bodies as opposed to the chemically treated wastewater that contains remnant chemicals.

Research on the use of Eps produced by bacteria isolated from cotton gin trash soils for removal of RB5 dye from textile wastewater has not been done before.

In Mexico, only 19.3 per cent of industrial water is treated (Green-Peace, 2014, pp. 3-4), whereas municipal treatment levels are approximately 50 per cent (CONAGUA, 2014a). This paper aims to focus on how the wastewater treatment plant policy, from a circular economy perspective, is affected by the governance context at the Presa Guadalupe sub-basin. Circular economy can contribute to water innovations that help in improving water quality. However, such benefits are not easily achieved. This case provides an example of the complexity and challenges that the implementation of a circular economy model can face.

Data are collected via semi-structured in-depth interviews with the stakeholders that are members of the Presa Guadalupe Commission. The contextual interaction theory (CIT) is the theoretical basis for this analysis (Boer de and Bressers, 2011; Bressers, 2009).

The findings show that the wastewater treatment plant policy plays an important role in a circular economy model. Some incentives towards a circular economy model are already in place; however, the hurdles of a top-down implementation perspective, low availability of resources, prioritisation of short-term results, lack of enforcement of the “polluter pays” principle and a linear model of water systems need to be overcome. If Mexico wants to move towards a circular economy model and if the government wants to enforce sustainable development principles, wastewater treatment is a challenge that must be addressed.

There are few studies in the circular economy literature that have analysed its implementation under a governance arrangement perspective.

Many countries all over the world are facing water shortages. As population increases, water is being perceived as a very valuable resource. Every effort is exerted to use water more efficiently and to make use of every drop of water to ensure the well being of future generations. New trends are developed and practiced in the area of water resources use and water saving. These trends vary from one country to another according to the degree of water scarcity, economic situations, and other factors. Developing non‐conventional water resources is an example of the recent trends in developing new water resources and water savings. Unlike rainfall, rivers, and groundwater which are considered conventional freshwater resources, the non‐conventional water resources include sea water desalination, agriculture wastewater reuse, and municipal wastewater reuse. This paper deals with the reuse of agriculture, municipal, and industrial wastewater as a new trend in developing additional water resources. Special interest is given to municipal wastewater, its characteristics and necessary treatment. Environmental and human health considerations for wastewater reuse, especially in agriculture, are also discussed. Possible consequences of wastewater reuse are introduced. Examples of wastewater reuse practices in some countries are also mentioned.

The textile industry is one of the largest and most important industrial sectors in India. Because the textile industry consumes large quantities of water and produces highly polluted water discharge, its environmental impact is high. Water is expensive to use, treat and dispose of. Therefore, water conservation and reuse are critical necessity for the textile industry because decreasing water and wastewater treatment and recycling costs can be beneficial.

This research neutralized the pH during dyeing industry wastewater treatment. The system should be robust to erroneous sensor measurements. A pH meter was developed and used to monitor the pH of wastewater hourly before and after HCl treatment.

HCl was used to neutralize the pH of wastewater from 9 to 7.5. The amount of HCl was optimized depending on the wastewater. Three wastewater treatment methods were used, namely, HCl, wash water and reverse osmosis (RO) treatments. The HCl treatment was the most effective for decreasing the pH; the wash water treatment was the most effective for decreasing the total dissolved solids (TDS), total suspended solids (TSS) total hardness and chemical oxygen demand; and the RO treatment was the most effective for decreasing the biochemical oxygen demand, TDS, TSS, total hardness and Cl⁻ concentration.

The pH should be monitored during the textile dyeing because the addition of color to textile fabrics is the most effective at neutral pH. This study evaluated several parameters of wastewater, including pH, color, TSS and TDS. The fabricated digital pH meter provided superior results than conventional measuring devices. The goal was to maintain a neutral pH during dyeing and recycle wastewater to improve environmental sustainability. The newly developed digital pH meter was less expensive and more precise than traditional pH meters. Before reusing and recycling, wastewater underwent ultrafiltration and RO treatment.

The purpose of this paper is to investigate the principles on how to reuse the reclaimed wastewater in urban areas and furthermore, to determine appropriate reuse targets and optimize the selection of reuse targets on wastewater.

Use Analytic Hierarchy Process (AHP) to suggest the assessment criteria and subject weights of wastewater reuse. Candidate reclaimed wastewater reuse targets in this study includes “agriculture irrigation,” “industrial use,” “environmental use,” “urban use,” “groundwater recharge,” “life-use water,” and “infusion reservoir.”

The analysis results of the pairwise comparison of the water targets under different assessment criteria level show that in all water targets, agriculture irrigation is more important than industrial use under the “public acceptance” at first. Then, the order results were used to suggest the future wastewater reuse targets under different assessment criteria levels and conducted an acceptance survey on the people of the urban areas.

The results of this study can be a useful information for the system analysis of wastewater reclamation and reuse.

The purpose of this study is to determine the barriers and constraints executive decision-makers have to face during the delivery method selection stage of water and wastewater projects using alternative project delivery (APD) methods, e.g. design-build (DB), design-build-operate (DBO) and construction management-at-risk (CMAR).

Structured interviews were conducted with 18 executive decision-makers from public agencies to identify the reasons for transitioning to APD from the design-bid-build (DBB) method. Respondents were also asked about the major obstacles they faced during the decision-making process, as well as key positive and negative factors in using APD methods. The executive decision-makers were also asked about their lessons learned during this process. In addition, this study collected key steps in making APD water and wastewater projects successful. All of the findings from the interview phase were validated by seven public agency executive decision-makers of water and wastewater industries.

One major study finding was that executive decision-makers chose the APD method because it provided cost and schedule benefits and the owner could also choose the designer or builder based on qualifications. The study also found that the main obstacles executive decision-makers faced were: (1) difficulty in implementing APD methods because they do not follow the low-bid process, (2) reluctance to use DB/CMAR because of the status quo and (3) unfamiliarity of city councils/elected commissions with the DB/CMAR process. The validation survey found that most findings from the initial phase of interviews were confirmed by the executives who took part in validation phase.

The major limitation of this research is the small sample size. As the executive decision-makers are very hard to reach for interviews, the authors failed to get interviews from a large number of them, despite repeated efforts made by the authors. Another limitation of this study is that the authors contacted most of the executive decision-makers listed in the WDBC list. These executive decision-makers worked for public agencies and, therefore, the views from private agencies could not be included in this research. The authors understand that the validation of the study findings is very important. However, due to the scope and limited time available for the research, the authors could not validate the findings of this study with other public agencies.

Selecting APD methods instead of DBB methods in water and wastewater projects for public agencies is a crucial issue during the project planning phase. Agencies' executive decision-makers need to understand the advantages and disadvantages of APD methods, along with the transition process in order to smoothly deliver projects. The findings of this study will assist public agency executive decision-makers to mitigate risks, overcome obstacles and become more educated about the APD method process, so that these projects can be successfully delivered within budget and on time.

This paper contributes to the existing body of knowledge by identifying lessons learned related to various APD method issues, which can be utilized by municipal executive decision-makers to successfully complete future APD projects.

All those effluent streams having compromised characteristics pose negative effects on the environment either directly or indirectly. Health care facilities and hospitals also generate a large amount of effluent like other industries containing harmful and toxic pharmaceutical residual compounds due to uncontrolled use of drugs, besides others. The occurrence of antibiotic in the environment is of utmost concern due to development of resistant genes. These get mixed up with ground and surface water due to lack of proper treatment of hospital wastewater. The effect of pharmaceutical compounds on human society and ecosystem as a whole is quite obvious. There are no strict laws regarding discharge of hospital effluent in many countries. Contrary to this, the authors do not have appropriate treatment facilities and solution to solve day by day increasing complexity of this problem. Moreover, water discharged from different health facilities having variable concentration often gets mixed with municipal sewage, thus remains partially untreated even after passing from conventional treatment plants. The purpose of this paper is to highlight the occurrences and fate of such harmful compounds, need of proper effluent management system as well as conventionally adopted treatment technologies nowadays all around the globe. This mini-review would introduce the subject, the need of the study, the motivation for the study, aim, objectives of the research and methodology to be adopted for such a study.

Hospital effluents consisting of pathogens, fecal coliforms, Escherichia coli, etc, including phenols, detergents, toxic elements like cyanide and heavy metals such as copper (Cu), iron (Fe), gadolinium (Gd), nickel (Ni), platinum (Pt), among others are commonly detected nowadays. These unwanted compounds along with emerging pollutants are generally not being regulated before getting discharged caused and spread of diseases. Various chemical and biological characteristics of hospital effluents are assessed keeping in the view the threat posed to ecosystem. Several research studies have been done and few are ongoing to explore the different characteristics and compositions of these effluent streams in comparison so as to suggest the suitable conventional treatment techniques and ways to manage the problem. Several antibiotic groups such as ciprofloxacin, ofloxacin, sulfa pyridine, trimethoprim, metronidazole and their metabolites are reported in higher concentration in hospital effluent. The aquatic system also receives a high concentration of pharmaceutical residues more than 14,000 μg/L from treatment plants also and other surface water or even drinking water in Indian cities. Many rivers in southern parts of India receives treated water have detected high concentration drugs and its metabolites. As far as global constraints that need to be discussed, there are only selected pharmaceuticals compounds generally analyzed, issue regarding management and detection based on method of sampling, frequency of analysis and observation, spatial as well as temporal concentration of these concerned micropollutants, accuracy in detecting these compounds, reliability of results and predictions, prioritization and the method of treatment in use for such type of wastewater stream. The complexity of management and treatment as well need to be addressed with following issues at priority: composition and characterization of effluent, compatible and efficient treatment technology that needs to be adopted and the environment risk posed by them. The problem of drugs and its residues was not seen to be reported in latter part of 20th century, but it might be reported locally in some part of globe. This paper covers some aspect about the disposal and regulatory standard around the world toward hospital effluent discharge, its managements and treatment technologies that are adopted and best suitable nowadays various industries and monitoring the efficiencies of existing treatment systems. This mini-review would introduce the subject, the need, the motivation and objectives of the study and methodology can be adopted for such a study.

The compiled review gives a complete view about the types of antibiotics used in different health care facilities, their residue formation, occurrences in different ecosystems, types of regulations or laws available in different counties related to disposal, different type of treatment technologies, innovative combined treatment schemes and future action needed to tackle such type of effluent after its generation. The thesis also highlights the use of certain innovative materials use for the treatment like nanoparticles. It also discusses about the residues impact on the human health as well as their bioaccumulative nature. If the authors relate the past to the current scenario of pharmaceutical compounds (PhACs) in the environment, the authors will certainly notice that many diseases are nowadays not curable by simple previously prescribed Ab. Many research projects have been done in European countries that have shown the risk of such residues like Pills, Sibell, Poseidon, No pills, Neptune, Knappe, Endetech, etc. In the previous section, it was mentioned that there are no stringent laws for hospital wastewater and in many countries, they are mixed with domestic wastewater. Many difficulties are there with this research due to complex analysis, detection of targeted Ab, affecting waterbodies rate of flow, nature of treatment varies with season to season. The way nature is being degraded and harmful effect are being imposed, it is important to take immediate and decisive steps in this area. Wastewater treatment plants (WWTPs) serves as a nursery for antibiotic-resistant systems, hence monitoring with great attention is also needed. Many trials with different treatment process, in combination, were considered. Many countries are paying great attention to this topic by considering the severity of the risk involved in it.

Previous studies by several scientists show that the pharmaceutical residues in the discharged effluent displayed direct toxic effects, and sometimes, detrimental effects in the mixture were also observed. The discharge of untreated effluent from hospitals and pharmaceuticals and personal care products in the natural ecosystem poses a significant threat to human beings. The pharmaceuticals, like antibiotics, in the aquatic environment, accelerate the development of the antibiotic-resistant genes in bacteria, which causes fatal health risks to animals and human beings. Others, like analgesics, are known to affect development in fishes. They also degrade the water quality and may lead to DNA damage, toxicity in lower organisms like daphnia and have the potential to bioaccumulate. A few commonly used nanoadsorbents for water and wastewater treatment along with their specific properties can also be used. The main advantages of them are high adsorption capacity and superior efficiency, their high reusability, synthesis at room temperatures, super magnetism, quantum confinement effect as well as eco-toxicity. This review will focus on the applicability of different nanoscale materials and their uses in treating wastewater polluted by organic and inorganic compounds, heavy metals, bacteria and viruses. Moreover, the use of various nanoadsorbents and nano-based filtration membranes is also examined.

A number of different pharmaceutical residues derived from various activities like production facilities, domestic use and hospitals have been reported earlier to be present in groundwater, effluents and rivers, they include antibiotics, psycho-actives, analgesics, illicit drugs, antihistamine, etc. In past few years environmental scientists are more concerned toward the effluents generated from medical care facilities, community health centers and hospitals. Various chemical and biological characteristics of hospital effluents have been assessed keeping in the view the common threats pose by them to the entire ecosystem. In this study, seven multispecialty hospitals with nonidentical pretreatment were selected for three aspects i.e. conventional wastewater characteristics, high priority pharmaceuticals and microbial analyses. The present work is to evaluate efficacy of advanced wastewater treatment methods with regard to removal of these three aspects from hospital effluents before discharge into a sewage treatment plant (STP). Based on test results, two out of seven treatment technologies, i.e. MBR and CW effectively reducing conventional parameters and pharmaceuticals from secondary and tertiary treatments except regeneration of microbes were observed in tertiary level by these two treatments.

This review has aimed to identify the emerging contaminants, including pharmaceutical residues, highly consumed chemicals that are present in the hospital effluent, along with their physicochemical and biological characteristics. In this, the main objective was to review the occurrences and fate of common drugs and antibiotics present in effluents from hospital wastewaters. As far as global constraints that need to be discussed, there are only selected pharmaceuticals compounds generally analyzed, issue regarding management and detection based on method of sampling, frequency of analysis and observation, spatial as well as temporal concentration of these concerned micropollutants, accuracy in detecting these compounds, reliability of results and predictions, prioritization and the method of treatment in use for such type of wastewater stream are among the major issues (Akter et al., 2012; Ashfaq et al., 2016; García-Mateos et al., 2015; Liu et al., 2014; Mubedi et al., 2013; Prabhasankar et al., 2016; Sun et al., 2016; Suriyanon et al., 2015; Wang et al., 2016; Wen et al., 2004). This paper covers some aspect about the disposal and regulatory standard around the world toward hospital effluent discharge, its managements and treatment technologies that are adopted and best suitable nowadays.

This study many multispecialty hospitals with nonidentical pretreatment were selected for three aspects i.e. conventional wastewater characteristics high priority pharmaceuticals and microbial analyses. The present work is to evaluate efficacy of advanced wastewater treatment methods with regard to removal of these three aspects from hospital effluents before discharge into an STP. Based on test results, two out of different treatment effectively reducing conventional parameters and pharmaceuticals from secondary and tertiary treatments except regeneration of microbes were observed in the tertiary level by these two treatments were studies followed by ozonation and ultraviolet-ray treatment.

A sustainable selection method for facility location of the water treatment is formulated by best–worst method. In addition, the model addresses the selection of appropriate technologies in the treatment plant, management of water leakage in the whole transmission network by using modernization and selection of different transmission technologies. Finally, the interaction between water and energy in this network seems to be paying particular attention.

Rapid population growth and urban development, and the constraints of water supply have become one of the crucial challenges around the world in the 21st century. Hence, the use of refined urban wastewater is increasing in many countries as an alternative source of water. In this regard, the rehabilitation of urban wastewater recycling and reuse has been proposed as one of the most suitable solutions for urban water management. Hence, in this paper, a mathematical model is formulated to design the simultaneous marketing of the urban water distribution network and wastewater treatment (including).

It seeks to ensure that energy is supplied through chemical methods to ensure that the system's energy dependence is on the national electricity grid. And in order to validate the model, a case study has been studied. By analyzing the results, it can be concluded that the upgrading of sewage treatment plants to replace underground water and water from nearby dams in household, agricultural and industrial applications will have positive environmental and economic impacts. One of the notable environmental impacts is the decline in groundwater and water scarcity in the coming years.

The summary of contributions is presented follow as: design and planning of water and urban wastewater integrated network; sustainable selection of facility location for the water treatment; capability selecting different treatment technologies in simultaneous design water and urban sewage supply chain; managing water leak in the network; proposed a water–energy nexus model in simultaneous design water and urban sewage supply chain; studying the feasibility of construction of power plants from biogas, the resulting of anaerobic digestion in treatment centers.

The paper seeks to assess the performance of 234 public and private water and wastewater utilities from industrialized and developing countries.

A group of financial and operational indicators was calculated for the sample utilities.

Some indicators calculated for the private sector, represented by US and UK water and wastewater utilities, demonstrated better values compared with public utilities, such as staff number per 1,000 connections and return on equity ratio and tariffs charged. On the other hand, the percentage of unaccounted‐for water and the debt to equity ratio evidenced no advantage in private over public utilities. Further, the performance of water and wastewater utilities of developing countries and Egypt does need improvement.

A key problem in most of water and wastewater utilities is the absence of performance assessment tools. To this end, this research utilized indicators as a means of performance assessment of water/wastewater utilities.