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1.
Int J Mol Sci ; 22(17)2021 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-34502052

RESUMO

The role of reactive oxygen species (ROS) in ABA-induced increase in hydraulic conductivity was hypothesized to be dependent on an increase in aquaporin water channel (AQP) abundance. Single ABA application or its combination with ROS manipulators (ROS scavenger ascorbic acid and NADPH oxidase inhibitor diphenyleneiodonium chloride (DPI)) were studied on detached roots of barley plants. We measured the osmotically driven flow rate of xylem sap and calculated root hydraulic conductivity. In parallel, immunolocalization of ABA and HvPIP2;2 AQPs was performed with corresponding specific antibodies. ABA treatment increased the flow rate of xylem, root hydraulic conductivity and immunostaining for ABA and HvPIP2;2, while the addition of antioxidants prevented the effects of this hormone. The obtained results confirmed the involvement of ROS in ABA effect on hydraulic conductivity, in particular, the importance of H2O2 production by ABA-treated plants for the effect of this hormone on AQP abundance.


Assuntos
Ácido Abscísico/farmacologia , Aquaporinas/metabolismo , Osmose , Proteínas de Plantas/metabolismo , Raízes de Plantas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Antioxidantes/farmacologia , Ácido Ascórbico/farmacologia , Inibidores Enzimáticos/farmacologia , Hordeum/efeitos dos fármacos , Hordeum/metabolismo , NADPH Oxidases/antagonistas & inibidores , NADPH Oxidases/metabolismo , Oniocompostos/farmacologia , Raízes de Plantas/efeitos dos fármacos , Xilema/efeitos dos fármacos , Xilema/metabolismo
2.
Water Sci Technol ; 84(6): 1389-1402, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34559074

RESUMO

Intense pressure on water resources has led to efforts to reuse reclaimed processing wastewater in the food industry. There are tight rules for water quality, but efficient separation technologies such as reverse osmosis possess good possibilities for water reuse. This study developed a membrane-based reuse water concept for wastewater from the candy industry emphasizing the pre-treatment stage in the concept to reduce fouling. The wastewater contained suspended solids, sugar compounds and the ingredients for candy gelation, which had a tendency to foul membranes, making pre-treatment essential for a successful concept. Cross-rotational ultrafiltration, which featured enhanced fouling prevention for membranes, functioned well for the removal of challenging substances. Conventional filtration technologies were impractical due to a low flux, even when the viscosity of the wastewater was reduced using surfactants. The wastewater had a high chemical oxygen demand, meaning that there was a strong fouling potential for reverse osmosis membranes, but also high osmotic pressure. A spiral wound reverse osmosis functioned well when the wastewater was pre-treated, and it produced good quality water with respect to all the other studied parameters except the chemical oxygen demand. However, chemical oxygen demand rejection was 99% since the concentration in the wastewater was originally very high.


Assuntos
Águas Residuárias , Purificação da Água , Doces , Membranas Artificiais , Osmose , Eliminação de Resíduos Líquidos , Águas Residuárias/análise , Água
3.
Water Res ; 204: 117631, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34536688

RESUMO

Sewage outbursts affect coastal environments as seawater is enriched with nutrients, organic matter and microbes, thus can potentially impair seawater reverse osmosis (SWRO) desalination. In this study, we evaluated how municipal sewage outbursts affect SWRO desalination in a pilot-scale system. To this end, feedwater characteristics (i.e., coastal water), the removal efficiency of organic foulants by a dual-media gravity filter, and cartridge micro-filtration were determined daily for 12 days. Permeate water flux was maintained constant during the study, while trans-membrane pressure (TMP) was automatically adjusted and continuously monitored. The results indicate that sewage outbursts caused an immediate (∼1 d) buildup of phyto/bacterioplankton biomass (up to 10-fold), and enhanced activity (maximal 30-fold) followed by an increase in transparent exopolymer particle (TEP) concentrations. After sewage addition, algal biomass was significantly removed by the pretreatment system (72-90%), while a considerable fraction of the bacterial biomass (42-65%) and TEP (53-65%) passed these procedures. The result was a negative impact on the desalination performance reflected by a significant increase (> 10%) in RO-TMP 7.5 d after the sewage addition. Our results indicate on a direct link between sewage outbursts, pretreatment efficiency, and SWRO desalination. Nevertheless, these findings can lead to new avenues for the development of science-based operational protocols to minimize the deleterious effects of abrupt sewage outbursts on SWRO desalination.


Assuntos
Esgotos , Purificação da Água , Membranas Artificiais , Osmose , Água do Mar
4.
Water Res ; 204: 117592, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34469809

RESUMO

As(III) species are the predominant form of arsenic found in groundwater. However, nanofiltration (NF) and reverse osmosis (RO) membranes are often unable to effectively reject As(III). In this study, we fabricate highly conducting ultrafiltration (UF) membranes for effective As(III) rejection. These membranes consist of a hydrophilic nickel-carbon nanotubes layer deposited on a UF support, and used as cathodes. Applying cathodic potentials significantly increased As(III) rejection in synthetic/real tap water, a result of locally elevated pH that is brought upon through water electrolysis at the membrane/water interface. The elevated pH conditions convert H3ASO3 to H2AsO3-/HAsO32- that are rejected by the negatively charged membranes. In addition, it was found that Mg(OH)2 that precipitates on the membrane can further trap arsenic. Importantly, almost all As(III) passing through the membranes is oxidized to As(V) by hydrogen peroxide produced on the cathode, which significantly decreased its overall toxicity and mobility. Although the high pH along the membrane surface led to mineral scaling, this scale could be partially removed by backwashing the membrane. To the best of our knowledge, this is the first report of effective As(III) removal using low-pressure membranes, with As(III) rejection higher than that achieved by NF and RO, and high water permeance.


Assuntos
Arsênio , Nanotubos de Carbono , Purificação da Água , Membranas Artificiais , Osmose , Ultrafiltração
5.
J Environ Manage ; 300: 113691, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34530367

RESUMO

The current study focused on the performance of a lab scale side stream anaerobic fertilizer drawn forward osmosis (An-FDFO) setup and optimization of nutrient rich solution to achieve sustainable water reuse from high strength synthetic textile wastewater. Three fertilizer draw solutes including Mono Ammonium Phosphate (MAP), Ammonium Sulphate (SOA) and Mono Potassium Phosphate (MKP) were blended in six different ratios with total molar concentration not exceeding 1 M. Among six blended draw solutions (DS), combination with high concentration of SOA have shown highest flux and combination with high concentration of MKP have shown highest reverse solute flux, while those with high concentration of MAP remain moderate both in flux and RSF. During long term runs, SOA: MKP (0.75: 0.25 M) showed longest filtration duration of 217 h in Run 1, with highest initial flux of 8.29 LMH and minimum dilution factor to achieve final nutrients concentration fit for direct fertigation, followed by Run 3 MAP: SOA: MKP (0.2: 0.6: 0.2 M) and then Run 2 MAP: MKP (0.75: 0.25). Moreover, deterioration of mixed liquor characteristics occurs in membrane tank due to high RSF. Similarly, the same inhibitory effect of reverse salt on biogas production was also assessed through Bio-Methane Potential experiments. However, Anaerobic Continuous Stirring Tank Reactor exhibited high performance efficacy, highlighting the importance of side stream submerged configuration in forward osmosis (FO) process.


Assuntos
Águas Residuárias , Purificação da Água , Anaerobiose , Membranas Artificiais , Nutrientes , Osmose , Rios , Têxteis
6.
Environ Sci Technol ; 55(18): 12664-12671, 2021 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-34494436

RESUMO

Forward osmosis (FO) has been increasingly used for water treatment. However, the lack of suitable draw solutes impedes its further development. Herein, we design pH-responsive polyoxometalates, that is, (NH4)6Mo7O24 and Na6Mo7O24, as draw solutes for simultaneous water reclamation and resource recovery from wastewater via FO. Both polyoxometalates have a cage-like configuration and release multiple ionic species in water. These characteristics allow them to generate high osmotic pressures to drive the FO separation efficiently with negligible reverse solute diffusion. (NH4)6Mo7O24 and Na6Mo7O24 at a dilute concentration (0.4 M) produce water fluxes of 16.4 LMH and 14.2 LMH, respectively, against DI water, outperforming the frequently used commercial NaCl and NH4HCO3 draw solutes, and other synthetic materials. With an average water flux of 10.0 LMH, (NH4)6Mo7O24 reclaims water from the simulated glutathione-containing wastewater more efficiently than Na6Mo7O24 (9.1 LMH), NaCl (3.3 LMH), and NH4HCO3 (5.6 LMH). The final glutathione treated with (NH4)6Mo7O24 and Na6Mo7O24 remains intact but that treated with NaCl and NH4HCO3 is either denatured or contaminated owing to their severe leakage in FO. Remarkably, both polyoxometalates are readily recycled by pH regulation and reused for FO. Polyoxometalate is thus proven to be an appropriate candidate for FO separation in wastewater reclamation and resource recovery.


Assuntos
Águas Residuárias , Purificação da Água , Concentração de Íons de Hidrogênio , Membranas Artificiais , Osmose , Compostos de Tungstênio
7.
Water Res ; 204: 117585, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34478993

RESUMO

Disposal of reverse osmosis concentrate (ROC) from advanced water purification facilities is a challenge associated with the implementation of reverse osmosis-based treatment of municipal wastewater effluent for potable reuse. In particular, the dissolved organic matter (DOM) present in ROC diminishes the quality of the receiving water upon environmental disposal and affects the toxicity, fate, and transport of organic contaminants. This study investigates UV-based advanced oxidation processes (UV-AOPs) for treating DOM in ROC using a Parallel Factor Analysis (PARAFAC) approach. DOM composition and degradation were tested in UV-only and three UV-AOPs using hydrogen peroxide (H2O2), free chlorine (Cl2), and persulfate (S2O82-). The four-component PARAFAC model consisted of two terrestrial humic-like components (CUVH and CVisH), a wastewater/nutrient tracer component (CNuTr), and a protein-like (tyrosine-like) component (CPrTy). Based on the observed loss in the maximum fluorescence intensity of the components, DOM degradation was determined to be dependent on UV fluence, oxidant dose, and dilution factor of the ROC (i.e., bulk DOM concentration). CVisH was most the photolabile component in the UV-only system, followed by CNuTr, CPrTy, and CUVH, respectively. Furthermore, UV-H2O2 and UV-S2O82- displayed faster overall reaction kinetics compared to UV-Cl2. The degradation trends suggested that CNuTr and CPrTy consisted of chemical moieties that were susceptible to reactive oxygen species (HO•) but not reactive chlorine species; whereas, CVisH was sensitive to all reactive species generated in the three UV-AOPs. Compared to other components, CPrTy was recalcitrant in all treatment scenarios tested. Calculations using chemical probe-based analysis also confirmed these trends in the reactivity of DOM components. The outcomes of this study form a foundation for characterizing ROC reactivity in UV-AOP treatment technologies, to ultimately improve the sustainability of water reuse systems.


Assuntos
Água Potável , Poluentes Químicos da Água , Purificação da Água , Análise Fatorial , Peróxido de Hidrogênio , Osmose , Raios Ultravioleta , Águas Residuárias , Poluentes Químicos da Água/análise
8.
J Environ Manage ; 300: 113781, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34560466

RESUMO

This work presents a novel concept for the integration of closed-circuit reverse osmosis (CCRO) technology and solvent-based precipitation as a means of producing an exceptional quality of water by separating the salts especially chlorides and sulphates from highly saline nanofiltration (NF) rejected stream of the steel industry. The NF rejected stream was extremely concentrated with salts like chloride (1560 mg/L), sulphate (4212 mg/L), manganese (28 mg/L), sodium (418 mg/L) and total dissolved solids (TDS), as high as 8100 mg/L, which are well above the permissible limit for surface discharge. The outcome of this work showed that reverse osmosis (RO) with continuous brine recycling achieved excellent desalination performance. Miscible organic solvents such as diisopropylamine (DIIPA), isopropylamine (IPA), and ethylamine (EA) were found to be effective in precipitating chloride and sulphate ions from highly concentrated RO brine. The overall removal efficiency of sulphate and chloride was found to be 99.88% and 91%, respectively. Preliminary treatment cost was estimated and found to be around 7.35 $/m3. The treated water can either be recycled in the system or safely released into the environment. The readers of this research article will be benefitted by gaining a thorough understanding of the treatment of concentrated brine from nanofiltration using an integrated RO-precipitation technique.


Assuntos
Purificação da Água , Filtração , Membranas Artificiais , Osmose , Reciclagem , Aço
9.
Molecules ; 26(16)2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34443451

RESUMO

Diabetes mellitus is characterized by tissue oxidative damage and impaired microcirculation, as well as worsened erythrocyte properties. Measurements of erythrocyte deformability together with determination of nitric oxide (NO) production and osmotic resistance were used for the characterization of erythrocyte functionality in lean (control) and obese Zucker diabetic fatty (ZDF) rats of two age categories. Obese ZDF rats correspond to prediabetic (younger) and diabetic (older) animals. As antioxidants were suggested to protect erythrocytes, we also investigated the potential effect of quercetin (20 mg/kg/day for 6 weeks). Erythrocyte deformability was determined by the filtration method and NO production using DAF-2DA fluorescence. For erythrocyte osmotic resistance, we used hemolytic assay. Erythrocyte deformability and NO production deteriorated during aging-both were lower in older ZDF rats than in younger ones. Three-way ANOVA indicates improved erythrocyte deformability after quercetin treatment in older obese ZDF rats only, as it was not modified or deteriorated in both (lean and obese) younger and older lean animals. NO production by erythrocytes increased post treatment in all experimental groups. Our study indicates the potential benefit of quercetin treatment on erythrocyte properties in condition of diabetes mellitus. In addition, our results suggest potential age-dependency of quercetin effects in diabetes that deserve additional research.


Assuntos
Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/tratamento farmacológico , Eritrócitos/metabolismo , Quercetina/uso terapêutico , Animais , Antioxidantes , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Deformação Eritrocítica/efeitos dos fármacos , Eritrócitos/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Óxido Nítrico/metabolismo , Osmose , Estresse Oxidativo , Quercetina/farmacologia , Ratos Zucker
10.
Int J Mol Sci ; 22(16)2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34445105

RESUMO

In grafted plants, the movement of long-distance signals from rootstocks can modulate the development and function of the scion. To understand the mechanisms by which tolerant rootstocks improve scion responses to osmotic stress (OS) conditions, mRNA transport of osmotic responsive genes (ORGs) was evaluated in a tomato/potato heterograft system. In this system, Solanum tuberosum was used as a rootstock and Solanum lycopersicum as a scion. We detected changes in the gene expression levels of 13 out of the 21 ORGs tested in the osmotically stressed plants; of these, only NPR1 transcripts were transported across the graft union under both normal and OS conditions. Importantly, OS increased the abundance of StNPR1 transcripts in the tomato scion. To examine mRNA mobility in transgrafted plants, StNPR1 and StDREB1 genes representing the mobile and non-mobile transcripts, respectively, were overexpressed in tobacco (Nicotiana tabacum). The evaluation of transgenic tobacco plants indicated that overexpression of these genes enhanced the growth and improved the physiological status of transgenic plants growing under OS conditions induced by NaCl, mannitol and polyethylene glycol (PEG). We also found that transgenic tobacco rootstocks increased the OS tolerance of the WT-scion. Indeed, WT scions on transgenic rootstocks had higher ORGs transcript levels than their counterparts on non-transgenic rootstocks. However, neither StNPR1 nor StDREB1 transcripts were transported from the transgenic rootstock to the wild-type (WT) tobacco scion, suggesting that other long-distance signals downstream these transgenes could have moved across the graft union leading to OS tolerance. Overall, our results signify the importance of StNPR1 and StDREB1 as two anticipated candidates for the development of stress-resilient crops through transgrafting technology.


Assuntos
Lycopersicon esculentum/genética , Osmose/fisiologia , Pressão Osmótica/fisiologia , Solanum tuberosum/genética , Tabaco/genética , Raízes de Plantas/genética , Plantas Geneticamente Modificadas/genética , Transgenes/genética
11.
Water Res ; 203: 117506, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34371231

RESUMO

The bacterial growth potential (BGP) of drinking water is widely assessed either by flow cytometric intact cell count (BGPICC) or adenosine triphosphate (BGPATP) based methods. Combining BGPICC and BGPATP measurements has been previously applied for various types of drinking water having high to low growth potential. However, this has not been applied for water with ultra-low nutrient content, such as remineralised RO permeate. To conduct a sound comparison, conventionally treated drinking water was included in this study, which was also used as an inoculum source. BGPICC, BGPATP, intact cell-yield (YICC), and ATP-yield (YATP) were determined for conventionally treated drinking water (Tap-water) and remineralised RO permeate (RO-water). In addition, both BGPICC and BGPATP methods were used to identify the growth-limiting nutrient in each water type. The results showed that the BGPICC ratio between Tap-water/RO-water was ∼7.5, whereas the BGPATP ratio was only ∼4.5. Moreover, the YICC ratio between Tap-water/RO-water was ∼2 (9.8 ± 0.6 × 106 vs. 4.6 ± 0.8 × 106 cells/µg-C), whereas the YATP ratio was ∼1 (0.39 ± 0.12 vs. 0.42 ± 0.06 ng ATP/µg-C), resulting in a consistently higher ATP per cell in RO-water than that of Tap-water. Both BGPICC and BGPATP methods revealed that carbon was the growth-limiting nutrient in the two types of water. However, with the addition of extra carbon, phosphate limitation was detected only with the BGPICC method, whereas BGPATP was not affected, suggesting that a combination of carbon and phosphate is essential for biomass synthesis, whereas carbon is probably utilised for cellular activities other than cell synthesis when phosphate is limited. It was estimated that the intact cell-yield growing on phosphate would be 0.70 ± 0.05 × 109 cells/µg PO4-P.


Assuntos
Água Potável , Purificação da Água , Trifosfato de Adenosina , Contagem de Células , Nutrientes , Osmose
13.
Environ Sci Technol ; 55(16): 11348-11359, 2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34342439

RESUMO

Predictive models for micropollutant removal by membrane separation are highly desirable for the design and selection of appropriate membranes. While machine learning (ML) models have been applied for such purposes, their reliability might be compromised by data leakage due to inappropriate data splitting. More importantly, whether ML models can truly understand the mechanisms of membrane separation has not been revealed. In this study, we evaluate the capability of the XGBoost model to predict micropollutant removal efficiencies of reverse osmosis and nanofiltration membranes. Our results demonstrate that data leakage leads to falsely high prediction accuracy. By utilizing a model interpretation method based on the cooperative game theory, we test the knowledge of XGBoost on the mechanisms of membrane separation via quantifying the contributions of input variables to the model predictions. We reveal that XGBoost possesses an adequate understanding of size exclusion, but its knowledge of electrostatic interactions and adsorption is limited. Our findings suggest that future work should focus more on avoiding data leakage and evaluating the mechanistic knowledge of ML models. In addition, high-quality data from more diverse experimental conditions, as well as more informative variables, are needed to improve the accuracy of ML models for predicting membrane performance.


Assuntos
Purificação da Água , Filtração , Aprendizado de Máquina , Membranas Artificiais , Osmose , Reprodutibilidade dos Testes
14.
Sci Total Environ ; 798: 149289, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34340085

RESUMO

Reverse osmosis (RO) is being used in many water reclamation facilities to produce high quality water that can be reused for different purposes. As a part of the RO process, a reject stream is produced as the reverse osmosis concentrate (ROC), which contains elevated levels of contaminants compared to the source water. Effective treatment and safe disposal of ROC via cost-effective means is very challenging. This study aims to develop a robust microbubble ozonation-biological process for industrial ROC treatment with a target effluent chemical oxygen demand (COD) lower than 60 mg/L. As compared to macrobubble ozonation, microbubble ozonation exhibited better ozone dissolution and 29% higher COD removal efficiency with the same ozone dosage. Under the optimum operating conditions with ozone dosage of 30 mg/L, ROC natural pH of 8.67 and ozonation duration of 1 h, microbubble ozonation achieved 42% COD removal efficiency while increasing the BOD5/COD ratio (ratio of biological oxygen demand over 5 days to the corresponding chemical oxygen demand) in ROC from 0.042 to 0.216. A biological activated carbon (BAC) column with an empty bed contact time (EBCT) of 120 min was combined with microbubble ozonation for continuous ROC treatment. Over the 100-day operation, the combined system performed consistent organics removal with an average effluent COD of 45 mg/L. Both LC-OCD data and fluorescence EEM spectra confirmed humic substances were the dominant organic species in ROC. Ozone pre-treatment could achieve significant removal of humic substances in raw ROC. ATP analysis found that ozone pre-treatment enhanced BAC biofilm activity by around 5 folds. 5 min acute toxicity assessment with Aliivibrio fischeri showed 4 times reduction of bioluminescence inhibition in ozone treated ROC. From the environmental point of view, Life cycle assessment (LCA) results demonstrated that Ozone-BAC system had significant environmental burdens on climate change and human toxicity due to the electricity production process. These environmental impacts can be mitigated by optimizing the ozonation process with reduced ozone dosage or utilizing renewable energy sources for electricity generation.


Assuntos
Ozônio , Poluentes Químicos da Água , Carvão Vegetal , Meio Ambiente , Humanos , Microbolhas , Osmose , Poluentes Químicos da Água/análise
15.
J Phys Chem Lett ; 12(28): 6469-6477, 2021 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-34240883

RESUMO

Many biological assays require effectively and sensitively sorting DNA fragments. Here, we demonstrate a solid-state nanopore platform for label-free detection and separation of short single-stranded DNA (ssDNA) fragments (<100 nt), based on their length-dependent translocation behaviors. Our experimental data show that each sized pore has a passable length threshold. The negative charged ssDNA fragments with length smaller than the threshold can be electrically facilitated driven through the correspondingly sized nanopore along the direction of electric field. In addition, the passable length threshold increases with the pore size enlarging. As a result, this phenomenon is able to be applicable for the controllable selectivity of ssDNA by tuning nanopore size, and the selectivity limitation is up to 30nt. Numerical simulation results indicate the translocation direction of ssDNA is governed by the competition of electroosmosis and electrophoresis effects on the ssDNA and offer the relationship between passable length threshold and pore size.


Assuntos
DNA de Cadeia Simples/análise , DNA de Cadeia Simples/isolamento & purificação , Nanoporos , Nanotecnologia/métodos , Eletroforese , Limite de Detecção , Osmose
16.
J Environ Manage ; 297: 113326, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34314966

RESUMO

Greenhouse cultivation in the Mediterranean region has undoubtedly enhanced the economic growth and has generated social benefits by making an efficient use of resources. However, these production systems caused undesirable environmental impacts. In order to move towards cleaner production in greenhouse areas, this study has assessed the potential environmental benefits and trade-offs of the integration of an on-farm reverse osmosis system powered by photovoltaic solar energy to recycle the drainage effluents from greenhouses. To that end, we compare the environmental footprint of a greenhouse tomato crop using this technology in a hydroponic system (HS), versus the conventional sanded soil 'enarenado' (CS) with free-drainage to soil. Additionally, for comparison, three independent irrigation sources (desalinated seawater with low electrical conductivity and two different mixes of underground and desalinated water, with moderate and high electrical conductivity, respectively) were evaluated. The use of desalinated seawater can help reduce the overexploitation of aquifers, although if the desalination process is not done with clean energy it also comes with a negative impact on the carbon footprint. Life Cycle Assessment (LCA) was used to analyse and evaluate six environmental impact indicators associated with these production systems and water treatments. In addition, a sensitivity analysis was conducted to explore the potential environmental benefits of increasing the use of renewable energy for desalinated water production, whilst also curbing the common over-fertilisation malpractice reported in the study area. Based on our findings, the HS with leachate treatment technology showed, compared to the CS system, a significant reduction in the eutrophication (72 %), although it did inevitably increase the depletion of fossil fuels (43 %) global warming (37 %) and acidification (32 %) impacts, due to the need for additional infrastructure and equipment. Among the inputs considered for the cultivation systems, the greenhouse structure, and the production of fertilisers and electricity for fertigation represented the highest environmental burdens. When comparing the three irrigation treatments, it was observed that the partial substitution of desalinated seawater by brackish groundwater substantially mitigated (27 %) the global warming footprint. The sensitivity analysis revealed that a significant reduction in the environmental impact is feasible.


Assuntos
Lycopersicon esculentum , Energia Solar , Hidroponia , Osmose , Água do Mar
17.
Chemosphere ; 281: 130796, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34289641

RESUMO

This paper describes the fabrication, modification, and evaluation of the performance of thin-film composite (TFC) forward osmosis (FO) membranes for lab-scale aquaculture wastewater recovery using various fumed silica (SiO2) nanoparticles. The active polyamide (PA) layers of these membranes were novelly modified using different types of pretreated SiO2 nanoparticles [virgin SiO2, dried SiO2, and 3-aminopropyltriethoxysilane (APTES)-modified SiO2] and concentrations (0.05, 0,1, 0,2, and 0.4 wt%) to improve the membrane hydrophilicity with minimum particle agglomeration. Results show that the APTES-SiO2 modified membrane had the highest water flux and selectivity, followed by the dried-SiO2 modified membrane. The APTES coupling agent notably reduced the SiO2 aggregation on the membrane surface and improved membrane hydrophilicity. Consequently, high permeate flux and an acceptable reverse solute flux were observed. The optimal SiO2 concentration for PA modification was 0.1 wt% for all the nanoparticle types. The virgin and APTES-SiO2 modified membranes were used for aquaculture wastewater recovery. The water recovery rate reached 47% in 84 h when using the APTES-SiO2 modified membrane, while it reached only 26% in 108 h when using the virgin membrane. With a suitable design of the filtration apparatus and choice of draw solution (DS), the prepared novel TFC-FO membrane containing APTES-modified SiO2 can be used for recycling aquaculture wastewater into the DS, which can then be reused for other purposes.


Assuntos
Nanopartículas , Purificação da Água , Aquicultura , Membranas Artificiais , Osmose , Dióxido de Silício , Águas Residuárias
18.
Environ Sci Technol ; 55(15): 10714-10723, 2021 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-34269563

RESUMO

Minimum and zero liquid discharge (MLD/ZLD) are emerging brine management strategies that attract heightened attention. Although conventional reverse osmosis (RO) can improve the energy efficiency of MLD/ZLD processes, its application is limited by the maximum hydraulic pressure (ΔPmax) that can be applied in current membrane modules. To overcome such limitation, novel RO-based technologies, including osmotically assisted RO (OARO) and low-salt-rejection RO (LSRRO), have been proposed. Herein, we utilize process modeling to systematically compare the energy consumption of OARO and LSRRO for MLD/ZLD applications. Our modeling results show that the specific energy consumption (SEC) of LSRRO is lower (by up to ∼30%) than that of OARO for concentrating moderately saline feed waters (<∼35,000 mg/L TDS) to meet MLD/ZLD goals, whereas the SEC of OARO is lower (by up to ∼40%) than that of LSSRO for concentrating higher salinity feed waters (>∼70,000 mg/L TDS). However, by implementing more stages and/or an elevated ΔPmax, LSRRO has the potential to outperform OARO energetically for treating high-salinity feed waters. Notably, the SEC of both OARO and LSRRO could be 50% lower than that of mechanical vapor compressor, the commonly used brine concentrator in MLD/ZLD applications. We conclude with a discussion on the practicability of OARO and LSRRO based on membrane module availability and capital cost, suggesting that LSRRO could potentially be more feasible than OARO.


Assuntos
Purificação da Água , Filtração , Membranas Artificiais , Osmose , Sais
19.
Int J Mol Sci ; 22(12)2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34203629

RESUMO

Drought and salinity are major constraints to agriculture. In this review, we present an overview of the global situation and the consequences of drought and salt stress connected to climatic changes. We provide a list of possible genetic resources as sources of resistance or tolerant traits, together with the previous studies that focused on transferring genes from the germplasm to cultivated varieties. We explained the morphological and physiological aspects connected to hydric stresses, described the mechanisms that induce tolerance, and discussed the results of the main studies. Finally, we described more than 100 genes associated with tolerance to hydric stresses in the Triticeae. These were divided in agreement with their main function into osmotic adjustment and ionic and redox homeostasis. The understanding of a given gene function and expression pattern according to hydric stress is particularly important for the efficient selection of new tolerant genotypes in classical breeding. For this reason, the current review provides a crucial reference for future studies on the mechanism involved in hydric stress tolerance and the use of these genes in mark assistance selection (MAS) to select the wheat germplasm to face the climatic changes.


Assuntos
Secas , Estudos de Associação Genética , Tolerância ao Sal/genética , Triticum/genética , Osmose , Salinidade
20.
Water Environ Res ; 93(10): 2329-2340, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34216398

RESUMO

Water is crucial for enhancing the yield of agricultural land to meet the growing demand. Forward osmosis (FO) is a developing technology that utilizes the natural osmotic gradient of solutions. In this study, fertilizer drawn FO setup was considered by using potassium chloride (KCl) as the draw solution (DS) for treating textile wastewater as the feed solution (FS). This study investigated the effects of FS temperature, pH, and FS and DS concentrations. The performance investigation involved the study in terms of water flux, reverse salt flux, and specific reverse salt flux. DS and FS properties, osmotic potential, and temperature played a vital role in the performance. At 30°C FS temperature, the highest water flux (5.5 LMH) was observed. Reverse salt flux increased due to the increase in solute diffusivity. The highest value of water flux was obtained at a DS of 1.150 M and FS of 1000 mg/L. The permeation of water improved due to the difference in DS and FS concentrations at pH values above 7. The results of this study suggest that KCl as DS has a higher potential for the treatment of textile wastewater at a temperature of 30°C. Additionally, the functional groups attached to the FO membrane were identified through Fourier-transform infrared (FTIR) spectroscopic study. PRACTITIONER POINTS: Treatment of textile wastewater with the use of fertilizer draw solution (KCl) by forward osmosis process as carried out. The performance was assessed in terms of water flux, reverse salt flux, and specific reverse salt flux. The effects of feed and fertilizer draw solution concentrations; pH and temperature were evaluated on the performance of FO process.


Assuntos
Fertilizantes , Purificação da Água , Concentração de Íons de Hidrogênio , Membranas Artificiais , Osmose , Temperatura , Têxteis , Águas Residuárias
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