Tertiary-treated Wastewater Research Articles

Identification of feasible regions for managed aquifer recharge in the Republic of Cyprus using a co-participative multi-criteria decision analysis

This study proposes an integrated approach that aims at finding locations which are eligible for Managed Aquifer Recharge (MAR) installation in Cyprus via the active involvement of key stakeholders of MAR-related sectors during all stages of the decision process to ensure the validity of the outcomes. The MAR problem is jointly formulated with the key stakeholders according to the site needs by introducing the so-called "MAR typology" concept, consisting of the recharge objective, the recharge method, and the available water sources. Tertiary-treated wastewater is adapted as the water source, which is recharged in aquifers via recharge ponds for irrigation. Various sources of information have been considered for assessing the degree of feasibility, aggregated in three thematic clusters (feasibility components), namely intrinsic site-suitability, the availability of water resources for MAR purposes, and water demand. Twelve criteria have been selected jointly with key stakeholders to evaluate the feasibility components via a GIS-MCDA process. Seven of these criteria are associated with the intrinsic suitability of a region (aquifer, land-use, and topographical properties), and five criteria are associated with the amount of water available for MAR (characteristics of the water source and evapotranspiration) and the crop irrigation needs. Stakeholder meetings were conducted to determine weights for each criterion and thematic cluster, leading to thematic and feasibility maps. The results demonstrate large discrepancies among the feasibility components in terms of their spatial variation and the location where the most favourable regions are present. Smoother profiles are observed for intrinsic suitability compared to the other thematic layers, partly attributed to the use of a larger number of criteria. Sensitivity analysis demonstrates that the MAR-favourable regions are weakly influenced by the variation of the relevant importance among the thematic layers, being mostly present in the vicinity of the southern and south-eastern coastlines.

A Comprehensive Review on the Use of Wastewater in the Manufacturing of Concrete: Fostering Sustainability through Recycling

The primary aim of this review article is to find the influence of wastewater and its characteristics on recycling as an alternative to potable water for concrete preparation. On the other hand, scarcity, and the demand for freshwater for drinking are also increasing day by day around the globe. About a billion tons of freshwater is consumed daily for concrete preparation for various operations such as mixing and curing, to name a few. The rapid development of certain industries such as textile, casting, stone cutting, and concrete production has caused the water supply to be severely affected. Recycling wastewater in concrete offers various potential benefits like resource conservation, environmental protection, cost savings, and enhanced sustainability. This article reviews the effect of various types of wastewater on various physical and chemical properties of wastewater, rheological characteristics, strength, durability, and microstructure properties of concrete. It also explores the potential effects of decomposing agents on enhancing concrete properties. Currently, limited research is available on the use of various types of wastewater in concrete. Hence, there is a need to develop various methods and procedures to ensure that the utilization of wastewater and treated wastewater is carried out in the production of concrete in a sustainable manner. Although wastewater can reduce the workability of fresh concrete, it can also increase its strength and long-term performance of concrete. The use of various types of wastewater, such as reclaimed water and tertiary-treated wastewater, was found to be superior compared to those using industrial- or secondary-treated wastewater. Researchers around the globe agree that wastewater can cause various detrimental effects on the mechanical and physical properties of concrete, but the reductions were not significant. To overcome limited scientific contributions, this article reviews all the available methods of using various types of wastewater to make concrete economically and environmentally friendly. This research also addresses possible challenges with respect to the demand for freshwater and the water crisis.

Utilization of treated water for building construction: A case study in Egypt

Due to rising living standards and population growth, saving fresh water will be a significant problem for the next generation. The Government is indirectly impacted by a significant financial burden due to the current usage of treated wastewater, in all of Egypt's districts. As a case study, Egypt's new administrative capital was chosen, given that it is today one of the most important cities and that its planning was predicated on making it a smart, sustainable city. The goal of the study was to develop methods for replacing potable water in the manufacture of concrete with tertiary-treated wastewater; however, used for concrete mixing or curing after concrete hardening. Property assessments of the fresh and hardened concrete were conducted, to ascertain the best water quality that can be used without compromising the quality or durability of the concrete. ; The results of this paper will serve as a guide for decision-makers looking to decrease costs and increase sustainability by using treated wastewater in making sustainable concrete for buildings, especially in recent decades, rising construction material usage has generated considerable environmental difficulties, particularly in the production of Ordinary Portland cement (OPC).

Understanding the influence of dissolved organic nitrogen characteristics on enhanced coagulation performance for water reuse

With the recent focus on using advanced water treatment processes for water reuse, interest is growing for utilizing enhanced coagulation to remove dissolved chemical species. Up to 85% of the nitrogen in wastewater effluent is made up of dissolved organic nitrogen (DON), but there is a knowledge gap regarding its removal during coagulation, which can be influenced by DON characteristics. To address this issue, tertiary-treated wastewater samples were analyzed before and after coagulation with polyaluminum chloride and ferric chloride. Samples were size-fractionated into four molecular weight fractions (0.45 μm, 0.1 μm, 10 kDa, and 3 kDa) using vacuum filtration and ultrafiltration. Each fraction was further evaluated by coagulating it separately to assess DON removal during enhanced coagulation. The size fractionated samples were also separated into hydrophilic and hydrophobic fractions using C18 solid phase extraction disks. Fluorescence excitation-emission matrices were used to investigate the characteristics of dissolved organic matter contributing to DON during the coagulation process. The results showed that DON compounds of size <3 kDa constituted a majority of the total DON. Coagulation removed more than 80% DON from size fractions 0.45 μm–0.1 μm and 0.1 μm-10 kDa, but less than 20% was removed from 10 kDa to 3 kDa and <3 kDa fractions. Coagulation on pre-filtered samples removed 19% and 25% of the <3 kDa DON fraction using polyaluminum chloride and ferric chloride, respectively. In all molecular weight fractions, hydrophilic DON compounds were found to be dominant (>90%), and enhanced coagulation was not effective in removing hydrophilic DON compounds. LMW fractions respond poorly to enhanced coagulation due to their hydrophilic nature. Enhanced coagulation effectively removes humic acid-like substances, but poorly removes proteinaceous compounds such as tyrosine and tryptophan. This study's findings provide insights into DON behavior during coagulation and factors affecting its removal, potentially improving wastewater treatment strategies.

Effect of long-term influx of tertiary treated wastewater on native bacterial communities in a dry valley topsoil: 16S rRNA gene-based metagenomic analysis of composition and functional profile.

Although dumping treated wastewater into soil might provide nutrients and organic matter, it can also expose the ecosystem to biological and chemical risks. A vital indication of soil health and quality is the soil microbial community. The current work used next-generation 16S rRNA gene amplicon sequencing to evaluate the effects of the long-term influx of tertiary treated wastewater (TWW) into Wadi Uranah, a dry valley in Makkah city, Saudi Arabia, on native topsoil bacterial community composition and predicted functions. The findings demonstrated that neither the compositions of microbial communities nor their predicted functions using PICRUSt2 differed significantly (p>0.05) between polluted valley soil (PolVS) and unpolluted valley soil (UPVS). Alpha and beta diversity, however, showed that the PolVS samples had a considerably higher level of diversity and variability. Firmicutes, Actinobacteria, Proteobacteria, and Bacteroidetes were the most prevalent phyla in both groups. Noticeable relative variations existed in some metabolic pathways such as cofactor, prosthetic group, electron carrier degradation, aldehyde degradation, and Entner-Doudoroff (ED) pathways. Overall, our findings suggest that because both groups have very similar core microbiomes and functions, the long-term disposal of tertiary TWW into Wadi Uranah may have little to no influence on the composition and function of soil bacterial communities. In addition, the long-term discharge of tertiary TWW after partially treated wastewater's initial disposal may have helped the native soil microbial community recover.

Tertiary wastewater treatment combined with high dilution rates fails to eliminate impacts on receiving stream invertebrate assemblages

The amount of wastewater processed in treatment plants is increasing following more strict environmental regulations. Treatment facilities are implementing upgrades to abate the concentrations of nutrients and contaminants and, thus, reduce their effects on receiving systems. Although many studies characterized the chemical composition and ecotoxicological effects of treated wastewater, its environmental effects are still poorly known, as receiving water bodies are often subjected to other stressors. We performed a field manipulative experiment to measure the response of invertebrate assemblages to one year of tertiary-treated wastewater discharges. We poured treated wastewater from an urban wastewater treatment plant into the lower-most 100-m of a previously unpolluted stream (3.6 % daily flow on average) while using another upstream reach as control. The positive correlation between effect sizes of abundance changes and IBMWP scores suggested assemblage modifications were following taxa tolerance to ecological impairment. The treatment increased the temporal variability of SPEARorganic, EPT relative abundance, and invertebrate functional redundancy. Our results show that even in this best-case scenario of tertiary-treated and highly diluted wastewater, the abundance of the most sensitive taxa in the aquatic assemblages is reduced. Further improvements in wastewater treatments seem necessary to ensure these effluents do not modify receiving water ecosystems.

Antibiotic resistance in soil and tomato crop irrigated with freshwater and two types of treated wastewater

Agricultural use of treated wastewater (TWW) is an effective means to reduce freshwater (FW) consumption. However, there is a growing concern regarding the potential dissemination of antibiotic resistance elements by TWW irrigation. We hypothesized that higher levels of antibiotic resistance genes (ARGs) would be detected in soil and crops irrigated with TWW compared to FW irrigation. To test our prediction, samples of water (FW, secondary TWW, and tertiary TWW), irrigated soils, and crops (tomato) surface wash were collected during two consecutive growing seasons. The ARGs conferring resistance to sulfonamide, fluoroquinolone, penicillin, erythromycin and tetracycline were quantified in the samples, alongside Class 1 integron-integrase and the bacterial 16 S rRNA encoding genes. Contrary to our hypothesis, ARGs in the irrigation water were not propagated to either the irrigated soil, or the tomato. The tomato surface wash featured a variety of ARGs that were undetected in neither the waters nor the irrigated soils. Therefore, we cautiously question the link between irrigation water quality and the soil and produce resistomes.

Cost Analysis and Health Risk Assessment of Wastewater Reuse from Secondary and Tertiary Wastewater Treatment Plants

Irrigation with reclaimed water is a widespread solution to coping with water scarcity, especially in the Middle East and North Africa (MENA) region. This paper presents a systematic evaluation approach of six treatment alternatives proposed for Alexandria WWTP in Egypt as an applied example. This approach evaluates the effluent quality and cubic meter price from the proposed treatment alternatives while managing the health risks associated with reclaimed water irrigation. Rotavirus, Salmonella, Giardia duodenalis, and Ascaris were studied as waterborne pathogens. A quantitative microbial risk assessment model was used for the estimation of annual infection risks. The exposure scenarios include farmers and vegetable consumers. Activated sludge provided the lowest costs; however, it gave the lowest efficiencies and highest health risks. On the other hand, the highest efficiency and lowest health risks were obtained by the membrane bioreactor. The resulting price of a cubic meter of treated wastewater, used in irrigation, ranged from 0.082 to 0.133 USD. Irrigation using tertiary-treated wastewater achieved the target infection risk for unrestricted irrigation without using advanced treatment facilities. The results of this study could give a comprehensive view of reusing wastewater to decision-makers to address both water and food poverty not only in Egypt but also in other countries in MENA with similar economic and agro-ecological conditions.

Changes in soil salinity under treated wastewater irrigation: A meta-analysis

In view of water shortages, the development and utilization of unconventional water resources have been studied extensively. Treated domestic or industrial wastewater used for agricultural irrigation is an unconventional water resource utilization method. Due to the particularities of water sources, previous studies have mainly focused on changes in soil heavy metals, microorganisms, and organic substances and crop responses to toxic elements; thus, attention to soil salinity is of secondary importance. After selecting qualifying research, a meta-analysis was performed to statistically analyze the data of seven variables (potassium (K), sodium (Na), calcium (Ca), magnesium (Mg), electrical conductivity (EC), pH, and yield) to 1) estimate the mean effects of treated wastewater (TWW) irrigation on the soil salinity, soil pH and crop yield; and 2) identify the wastewater treatment grade (primary treated wastewater (PTW), secondary treated wastewater (STW), and tertiary treated wastewater (TTW)) and soil texture (sandy texture, loamy texture and clayey texture) that benefit TWW irrigation. The results showed that TWW irrigation caused a significant accumulation of soil salinity, and the increase in cation content from high to low was K (90.1%), Na (59.9%), Mg (25.2%) and Ca (17.3%). EC also increased significantly by approximately 57.2%, while there was no significant change in pH, and even the crop yield presented an average reduction of nearly 6.5%. PTW contributed to the largest salt accumulation, followed by TTW and STW. STW showed a significant increase in EC but did not show a significant change for the four ions. In terms of yield, STW can increase yield, while TTW has the opposite effect. In general, the sandier the soil texture, the higher is the salt content detected, although the retention of salt in loamy textured soil may differ depending on the ions. The yield of crops grown increased in the clayey textured soil and decreased in the loamy textured soil. Our study elucidated the response of soil salinity accumulation under TWW irrigation and could provide a reference for unconventional water resource utilization.

Ultrafiltration Process in Disinfection and Advanced Treatment of Tertiary Treated Wastewater.

The paper presents the results of research on the use of ultrafiltration, using membranes of 200 and 400 kDa separation, for disinfection of municipal treated wastewater. The research was conducted on a fractional technical scale using real municipal treated wastewater from two large wastewater treatment plants treating most of the wastewater over the one-million polycentric Gdańsk agglomeration (1.2 million inhabitants). UF 200 kDa and UF 400 kDa processes enabled further improvement of the physical and chemical parameters of treated wastewater. Total phosphorus (to below 0.2 mg/L–UF 200 kDa, 0.13 mg/L–UF 400 kDa) and turbid substances (to below 0.2 mg/L, both membranes) were removed in the highest degree. COD was reduced efficiently (to below 25.6 mgO2/L–UF 200 kDa, 26.8 mgO2/L–UF 400 kDa), while total nitrogen was removed to a small extent (to 7.12 mg/L–UF 200 kDa and 5.7 mg/L–UF 400 kDa. Based on the reduction of indicator bacteria; fecal coliforms including E. coli (FC) and fecal enterococci (FE) it was found that the ultrafiltration is an effective method of disinfection. Not much indicator bacterial were observed in the permeate after processes (UF 200 kDa; FC—5 CFU/L; FE—1 CFU/L and UF 400 kDa; FC—70 CFU/L; FE—10 CFU/L. However, microscopic analysis of prokaryotic cells and virus particles showed their presence after the application of both membrane types; TCN 3.0 × 102 cells/mL–UF 200 kDa, 5.0 × 103 cells/mL–UF 400 kDa, VP 1.0 × 105/mL. The presence of potentially pathogenic, highly infectious virus particles means that ultrafiltration cannot be considered a sufficient disinfection method for treated wastewater diverted for reuse or discharged from high load wastewater treatment plants to recreational areas. For full microbiological safety it would be advisable to apply an additional disinfection method (e.g., ozonation).

Concrete mix using tertiary treated wastewater and effect of ambient and elevated temperatures on its properties

The aim of this study is to investigate the effect of using tertiary treated wastewater (TTWW) on concrete mixes exposed to high temperatures (up to 800°C) with different water cement ratios (0.5, 0.6, and 0.7). Slump, percentage of air content, density of concrete, and setting times were tested on freshly mixed concrete. The properties of the concrete tested were setting time, compressive strength at ambient (at 3, 7, 21, 28 and 35 days) and elevated temperatures (up to 800°C), and the flexural strength (at 28 days). The compressive strength of concrete made with TTWW, as well as curing in potable water (PW) and tertiary wastewater, was found to be in the range of 85-95% of normal concrete, which satisfies ASTMC-94 norms. The flexural strength of concrete made using TTWW, exhibited significant differences to the control concrete. This study indicated that the properties of concrete mixed with TTWW are within acceptable limits under varied conditions.

Characterization of clogging deposits in an irrigation pipeline and effect of post-aeration on clogging potential of tertiary-treated wastewater.

In Agadir, a water-scarce Moroccan region, municipal and industrial wastewater is tertiary-treated to be reused in golf courses. Wastewater reuse has been constrained by severe clogging of emitters, which caused technical and financial problems. This study aimed to perform an in-depth characterization of the treated wastewater (TWW) in relation to its susceptibility to cause clogging, and to assess the capacity of an aeration post-treatment to reduce the clogging potential. The post-treatment consisted of injecting different airflows (0-33 L/(h Lreactor) into the TWW. The structural, morphological and elemental composition of the clogging matter collected in the irrigation pipeline was characterized using scanning electron microscopy, scanning transmission electron microscopy, X-ray diffraction and X-ray energy dispersive spectroscopy. The 15-day aeration post-treatment at 16.5 L/(h Lreactor) presented the best cost-benefit ratio. Organic matter was totally degraded. Calcium was reduced by 9%, bicarbonates by 54%. The analysis of the deposits induced by the aeration post-treatment revealed a relevant decrease of the major constituents of the clogging deposits found in the irrigation pipeline. The results show the effectiveness of post-aeration in biodegrading residual organic matter and precipitating several salts, thus reducing the clogging potential.

Evaluation of a recirculating hydroponic bed bioreactor for removal of contaminants of emerging concern from tertiary-treated wastewater effluent

Tertiary-treated effluent from a municipal wastewater treatment plant in Tucson, AZ, was added to recirculating hydroponic bed bioreactors filled with light expanded clay aggregate (LECA) and recirculated for 10 days. Bioreactors were planted with high and low densities of sorghum (Sorghum bicolor), switchgrass (Panicum virgatum) and Bacillus thuringiensis cotton (Gossypium sp.). The experiment also included a non-planted bioreactor treatment and a control bioreactor with neither plants nor substrate medium. Of 46 contaminants of emerging conern assayed with liquid chromatography tandem mass spectrometry (LC-MS/MS), 16 were initially identified at detectable levels in the effluent. After one day, concentrations of Ibuprofen and Diphenhydramine fell below detection limits in all treatments as well as the control. After five days, initial concentrations of atenolol, benzotriazole, carbamazepine, hydrochlorothiazide, iohexol, iopamidol iopromide, primidone, sulfamethoxazole and tris TCPP were reduced by greater than 80% in all treatments, while the control exhibited little to no removal. Diclofenac, simazine and sucralose exhibited variable removal rates among treatments ranging from 44 to 84% after five days. After 10 days, concentrations of DEET, diclofenac, iopromide, primidone and simazine were all below detection levels, while there was near zero removal in the control. Bioreactors planted with cotton had significantly more removal of sulfamethoxazole than unplanted bioreactors by 16–19% after five days and by an additional 18–20% removal after 10 days. The percentage uptake of benzotriazole by every planted treatment was significantly higher than the non-planted treatment after five and 10 days. Significant contaminant removal occurred in the media substrate, likely through adsorption to LECA or microbial degradation. More research is needed to examine specific pathways of degradation and removal by various microbials and plants.

Tertiary-treated wastewater as a potential water source for sustainable aquaculture: A laboratory-scale experiment with Cyprinus carpio

Aquaculture in treated wastewater (TWW) has been practiced around the world, yet this field of research is backed with only scant scientific data, especially the aspect of the bioaccumulation of organic micropollutants (OMPs) in fish. The objectives of this study were to evaluate how fish culture in tertiary TWW (TTWW) affects commercially important traits, such as fish survival, growth rate and health, and to assess the potential risks associated with food safety and consumer protection. Cyprinus carpio juveniles were raised in 0%, 50% and 100% TTWW, for five months. Fish performance and health parameters were not affected by exposure to TTWW. The levels of heavy metals in the fish muscle were below the FAO and EU maximal permitted levels in edible fish. Seven out of 40 screened OMPs were detected in the TTWW samples at least once. Out of the 19 analyzed OMPs in fish tissues, four were detected in exposed fish. Carbamazepine and diclofenac were detected in the muscles and livers of fish grown in 50% and 100% TTWW at measurable concentrations. Carbamazepine-epoxide and diphenhydramine concentrations were below the limit of quantification (LOQ) in the muscle of the exposed fish, while diphenhydramine was detected above the LOQ level in two liver samples of fish grown in 100% TTWW. Based on the presented findings, TTWW can be successfully used for growing fish, and TTWW-grown fish met all the existing standards for heavy metals accumulation. However, the issue of OMP's bioaccumulation needs to be further studied in different fish species and culture conditions to broaden the perspective of the findings.

Aquifer storage and recovery, and managed aquifer recharge of reclaimed water for management of coastal aquifers

The hydrological and economic feasibility of aquifer storage and recovery (ASR) of excess desali-nated water and managed aquifer recharge (MAR) using tertiary treated wastewater (TTWW) to manage stressed coastal aquifers in Oman has been studied numerically using the code, MODFLOW 2005 and the different transport packages MT3DMS, and MODPATH. The current ASR study aims to assess the feasibility of saving and recovering water for the purpose of supply to the city of MUSCAT during high demand periods by banking excess-desalted water during winter and recover it during the rest of the year. The second objective of the study is to explore the feasibility of MAR using TTWW to mitigate salinity in two costal aquifers in North of Oman exploited for different purposes: domestic water supply (Al-Khod aquifer), and for irrigation purposes (Jamma aquifer). ASR in the Al-Khod Aquifer was explored using Simulation Optimization multi-objective modeling using evolutionary algorithm NSGA-II (namely, the Non-dominated Sorting Genetic Algorithm-II), to generate the set of Pareto optimal solutions according to recharging scenarios. The results show that the potential net benefit of storage and recovery might reach as high as 17.80 million/year. The maximum profitable volume that can be recharged into the aquifer, given the limited number of wells and their locations, is estimated at 8.4 Mm3/year, which is lower than the current excess estimated of 10 Mm3/year. For MAR using TTWW, different managerial scenarios were simulated and analysis of the results reveals that the Jamma aquifer will further deteriorate in the next 20 years if it remains poorly managed. The groundwater level will decline further to exceed 3 m on average, and the iso-concentric salinity line of 1,500 mg/L will advance 2.7 km inland that will severely affect farming activities in the area. However, MAR using TTWW when integrated with the management of groundwater abstraction (e.g., smart water meter, higher irrigation efficiency to reduce the abstraction rate) becomes hydrologically feasible to augment the aquifer storage and controlling seawater intrusion, and hence sustains farming activities. The economic analyses of such situation recommend: (1) injecting TTWW in the vicinity of irrigation wells; (2) investing in smart water meters and online control of pumping from the wells to reduce the abstraction rate by 25; and (3) a combination of both are feasible scenarios with positive net present values. Recharge in upstream areas is found not economically feasible because of high investment cost of the installation of pipes to transport the TTWW over a distance of 12.5 km. Because the financial resources for investments are limited, scenario (2) shows a Net Benefit Investment Ratio of 4.41 (i.e., investment of a 1 yields 4.41). Although option (3) shows the lowest Net Benefit Investment, it is very attractive from a social perspective because it entails an integrated demand and supply management of groundwater. Farmers are requested to reduce pumping, and the gov-ernment will invest in injecting TTWW to improve groundwater quality in the vicinity of irrigation wells and to form a hydrological barrier to control seawater intrusion in the long run. The primary objective of MAR for the Al-Khod aquifer is to increase the urban water supply and to sustain the aquifer service with the lowest possible damages from seawater intrusion. A number of managerial scenarios were simulated and progressively developed to reduce seawater intrusion and outflow of the groundwater to the sea. An economic analysis was conducted to characterize the trade-off between the benefits of MAR and seawater inflow to the aquifer under increased abstraction for domestic supply. The results show that the abstracted volume for domestic supply can be doubled under MAR practices if irrigation wells are properly managed and public wells are better located. Even though injection of TTWW is more expensive (due to the injection cost), will result in higher benefits. The results indicate that managing the aquifer would produce a net benefit ranging from 8.22 million to 15.21 million compared with 1.57 million with the current practice. MAR using TTWW is feasible to develop water resources in arid regions, and the best scenario depends on the decision maker’s preference when weighing the benefits of MAR and the level of damage to the aquifer. MAR, as a smart water governance technology, mitigates stresses on aquifer systems in arid zones, maximizes the benefit of using groundwater for both agricultural and domestic purposes while minimizing the adverse socio-hydrological and agricultural consequences of mismanagement of commingled groundwater-TTWW resources at all scales (national, catchment, metropolitan area, village, farm). © 2020 Desalination Publications. All rights reserved.

Effects of the Irrigation with Treated Wastewaters on the Proximate Composition, Mineral, and Polyphenolic Profile of the Globe Artichoke Heads [Cynara cardunculus (L.)

The present work was carried out to evaluate the effects of irrigation with two different municipal wastewaters (secondary-treated wastewater (SW) and tertiary-treated wastewater (TW)) compared to freshwater (FW) on main qualitative parameters of three different classes of globe artichoke (main, secondary, and processing heads). The experimental trial was conducted in Southern Italy (Apulia region) for two cropping cycles (GS1 and GS2) using ‘Violetto di Provenza’ as cultivar. The artichoke heads were analyzed for proximate composition (dry matter, total sugar, total fat, ash, and total protein), percentage of edible part, mineral profile (sodium, potassium, magnesium, calcium, copper, iron, nickel, zinc, chloride, nitrate, phosphate, and sulphate) and polyphenolic acids content (caffeoylquinic acids and flavones). Both SW and TW treatments caused an increase of the percentage of the edible part, head protein contents, and mineral elements of the main and processing heads. Moreover, SW statistically increased the caffeoylquinic acid derivatives and the trans-ferulic acid content, while both SW and TW the flavones content. Finally, according to the multivariate analysis adopted, in our experimental conditions, the mineral component of the heads, such as chloride, potassium, copper, and zinc content, had a greater weight in the separation of FW, SW, and TW. On the other hand, the polyphenolic 5-O-caffeoylquinic acid, trans-ferulic acid, and 1,5-di-O-caffeoylquinic acid had a greater weight in the separation of the head class groups (main, secondary, and processing). Moreover, the trans-ferulic acid content of the heads was related both to the irrigation water type and to the different head classes.

The effect of tertiary treated wastewater on fish growth and health: Laboratory-scale experiment with Poecilia reticulata (guppy).

Treated wastewater (TWW) constitutes a sustainable water resource and has been used for fish culture in some countries around the world, although there are no comprehensive data on the effect of TWW on fish growth and health in the context of aquaculture production. Our objectives were to examine how fish culture in TWW affected fish growth and fitness, as well as compliance with the international standards for safe consumption. Guppy (Poecilia reticulata) fingerlings were reared in 0%, 50% and 100% tertiary TWW (TTWW), from the age of five days, for a period of four months. In water analyses, 33 out of 67 tested organic micropollutants (OMPs) were detected in the TTWW samples at least once, at concentrations that are typically reported in domestic TTWW. Fish survival ranged between 77–80% and did not differ between treatment groups. Fish growth and mortality following challenge infection with Tetrahymena sp. (which ranged between 64–68%), were similar among treatment groups. Of tested immunological parameters, lysozyme and anti-protease was similar among treatments while complement activity was highest in the 50% TTWW-reared fish. No abnormalities were observed in the histopathological analysis. Levels of heavy metals, polychlorinated-biphenyls (PCBs) and organochlorines (OCs) in fish were below the detection limit and below the Food and Agriculture Organization of the United Nations (FAO) and the European Union EU maximal permitted levels in food fish. Results suggest that the yield of fish grown in TTWW is potentially similar to that in freshwater, and the produced fish comply with the standards of consumer safety. The results are in line with previous studies that examined the feasibility of TWW-fed aquaculture.

SOIL CHEMICAL PROPERTIES IN BANANA CROPS FERTIGATED WITH TREATED WASTEWATER

ABSTRACT Determining the effects of using wastewater as fertilizer on soil chemical properties allows a safe reuse of this effluent in agriculture. This study evaluated the effects of fertigation with tertiary treated wastewater (TTW) from the Janaúba sewage treatment plant on chemical properties of a Latosol (Oxisol) with banana crops of the Prata-Anã cultivar in the semiarid region of Brazil. A randomized complete block design with four replications was used to test four TTW rates (70%, 130%, 170%, and 200% of the limit of 150 kg ha-1 year-1 of Na that can be applied to the soil) and compare them to a control without TTW. Soil samples from the 0.0-0.2, 0.2-0.4, 0.4-0.6, and 0.6-0.8 m layers were collected at the end of the first crop cycle to evaluate soil chemical properties-pH, soil organic matter (SOM), P, K, Na, Ca, Mg, Al, potential acidity (H+Al), base saturation, B, Cu, Fe, Mn, Zn, remaining P, and electrical conductivity (EC). The use of TTW increases soil pH and decreases exchangeable Al content, thus, reduces the need for liming. However, Na contents increased faster than EC in the soil, indicating that the use of TTW tends to alter soil physical properties over time. The use of TTW had no effect on the soil OM, P, Ca, Mg, and micronutrients contents, potential acidity, and base saturation. The changes in soil chemical attributes observed at the end of the first crop cycle were not limiting to the banana crop.

Hydrological and economic feasibility of mitigating a stressed coastal aquifer using managed aquifer recharge: a case study of Jamma aquifer, Oman

This study explored the hydrological and economic feasibility of managed aquifer recharge (MAR) using tertiary treated wastewater (TWW) to mitigate salinity in the coastal aquifer of Jamma, Oman. A steady-state groundwater flow and transport model, using MODFLOW software, was developed and calibrated. Different managerial scenarios were simulated and the results reveal that the Jamma aquifer will be further deteriorated in the next 20 a if it remains unmanaged. The groundwater table will decline further by more than 3 m on average; and the iso-concentration salinity line of 1500 mg/L will advance 2.7 km inland, which will severely affect the farming activities in the area. However, MAR using TWW when integrated with the management of groundwater abstraction (e.g., using modern irrigation systems to reduce the abstraction rate) becomes hydrologically feasible to augment the aquifer storage and control seawater intrusion, and hence improves the farming activities. The results indicate that: (1) injecting TWW in the vicinity of irrigation wells (Scenario A2); (2) investing in smart water meters and online control of pumping from the wells to reduce the abstraction rate by 25% (Scenario B); and (3) a combination of both (Scenario B2) are feasible scenarios with positive net present values. Recharge in upstream areas is found not economically feasible because of the very high investment cost of the installation of pipes to transport the TWW over a distance of 12.5 km. Because of securing funds are challenging, Scenario B would be the best option and the second-best option is Scenario A2. Scenario B2 has the lowest net benefit investment ratio and is very attractive because it entails integrated demand and supply management of groundwater. It is required to reduce pumping and to invest in injecting TWW to improve groundwater quality in the vicinity of irrigation wells and to form a hydrological barrier to control seawater intrusion in the long run.

Effect of wastewater on properties of concrete

Water is one of nature's precious gifts to humanity. It was the most common liquid with the highest usage of all liquids on the globe. This elixir of lives is a restricted natural resource. Hence, even a drop should not be wasted and now it's time for its systematic use. Construction industry requires a lot of water for infrastructure. Therefore, use of treated wastewater in construction industries is gaining grounds in so many countries of the world. The proper selection and processing of treated wastewater may be helpful in manufacturing concrete. This research aim was to find the possibility of the usage of treated wastewater in concrete as an alternative to potable water by conducting comprehensive laboratory investigations for a better understanding of mechanical and durability properties of treated wastewater concrete. The samples of water used were tertiary treated wastewater (TTWW), secondary treated wastewater (STWW) and tap water (TW). Compressive strength test, flexural strength test, chloride penetration resistance, carbonation resistance and abrasion resistance test were carried out for each concrete mixes. Tap water was replaced with treated wastewater to 100% by weight. In this study water to cement ratio was taken as 0.47. For compressive strength, concrete cubes for 7, 28 and 90 days were cast and for flexural strength beams were cast for 28 and 90 days as well as durability test was carried out after the 28 days. The results of compressive strength of concrete after replacement of 100% tap water with tertiary treated wastewater in concrete mixing as well as curing in tap water and tertiary wastewater is found to be in the range of 85–94% of normal concrete, which satisfies ASTM C-94 norms. The flexural strength of tertiary treated wastewater with tap water curing and tertiary treated wastewater with TTWW curing shows significant results as compared to control concrete. The depth of carbonation observed lower in control concrete as compare to all mixes. The experimental results indicated that the chloride concentration of concrete samples increased with a decrease in the quality of mixing water.