Editorial

3 pages, 184 KiB

Open AccessEditorial

Technologies for Water Reuse: Current Status and Future Challenges

by Mauro Capocelli and Vincenzo Piemonte

Water 2021, 13(6), 832; https://doi.org/10.3390/w13060832 - 18 Mar 2021

Viewed by 2066

Water is fundamental for the quality of both ecosystems and society, and plays a key role for energy and food production, a prerequisite for the sustainable development [...] Full article

(This article belongs to the Special Issue Technologies for Water Reuse: Current Status and Future Challenges)

Research

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21 pages, 6569 KiB

Open AccessArticle

An Improved Configuration of Vertical-Flow Mesh Tube Filters for Seawater Pretreatment: Performance, Cleaning, and Energy Consumption

by Dong-Ho Kim, Changkyoo Choi, Chulmin Lee, Rusnang Syamsul Adha, Thanh-Tin Nguyen, Sang-Jun Ahn, Hee-Jong Son and In S. Kim

Water 2020, 12(10), 2804; https://doi.org/10.3390/w12102804 - 10 Oct 2020

Cited by 4 | Viewed by 2843

Abstract

Roughing filters are types of porous media filter used in pretreatment systems where the raw water contains a large amount of suspended particles (SPs) and organic matter. Mesh tube filtration (MTF) media are roughing-filter media composed of low-density polyethylene used for SP removal [...] Read more.

Roughing filters are types of porous media filter used in pretreatment systems where the raw water contains a large amount of suspended particles (SPs) and organic matter. Mesh tube filtration (MTF) media are roughing-filter media composed of low-density polyethylene used for SP removal during wastewater treatment. In this study, we present an improved MTF design—a porous filter bed (PFB), which exhibits superior SP removal performance compared to conventional MTF media. We then compare the applicability of MTF and PFB to both the primary pretreatment process for seawater desalination and the water reuse process. In bench-scale SP removal experiments, PFB shows removal rates of 46.7%, 68.0%, 67.6%, and 68.4% at hydraulic retention times of 15, 20, 30, and 60 min, respectively, which are better than those of MTF. The specific energy consumption (SEC) of batch dissolved air flotation (DAF) was known to range from 0.035 to 0.047 kWh/m³, whereas the SEC calculated for pilot-scale MTF and PFB is 0.027 kWh/m³ and minimum energy for influent supply, respectively. This suggests that PFB can compete with DAF as a primary pretreatment process. MTF predominantly removes SPs by sedimentation, whereas SP removal in PFB typically occurs via deposition of SPs on the mesh tube media. Full article

(This article belongs to the Special Issue Technologies for Water Reuse: Current Status and Future Challenges)

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24 pages, 2030 KiB

Open AccessArticle

Factors That Limit the Adoption of Biofloc Technology in Aquaculture Production in Mexico

by Erick Arturo Betanzo-Torres, María de los Ángeles Piñar-Álvarez, Luis Carlos Sandoval-Herazo, Antonio Molina-Navarro, Isidro Rodríguez-Montoro and Raymundo Humberto González-Moreno

Water 2020, 12(10), 2775; https://doi.org/10.3390/w12102775 - 05 Oct 2020

Cited by 8 | Viewed by 5094

Abstract

Aquaculture uses large volumes of water, which is generally discharged without treatment, possibly causing scarcity and contamination. A sustainable aquaculture option is biofloc technology (BFT), which recycles food residues and toxic organic and inorganic compounds from the system through microorganisms, avoiding excessive use [...] Read more.

Aquaculture uses large volumes of water, which is generally discharged without treatment, possibly causing scarcity and contamination. A sustainable aquaculture option is biofloc technology (BFT), which recycles food residues and toxic organic and inorganic compounds from the system through microorganisms, avoiding excessive use of water and serving as natural food for cultured aquatic organisms. The aim of this study was to identify the main factors that limit a Mexican aquaculture producer from adopting biofloc technology in their aquaculture production units (APUs). Strengths and weaknesses were methodologically analyzed through 248 questionnaires, applied to fish farmers in 16 states of the country with a mixed approach (quantitative and qualitative). Findings reveal that the main obstacles in the use of BFT are due to the following: low academic level, limited administrative capacity, scarce technological equipment in facilities, diversified productive activity, and obsolete regulations. Other factors that promote the adoption of BTFs for aquaculturists are production experience, favorable weather conditions, and abundant availability of water and energy. In conclusion, the use of BTF is a sustainable option for APUs despite the limiting factors identified in this research which slow down the growth of the sector. It is advisable to study Mexican producers with BFT, in order to spread their benefits to other APUs, and further evaluate the productivity of the aquaculture sector. This study considers production aspects, and also sustainable use of its resources, specifically, surface, energy, water, and food. Full article

(This article belongs to the Special Issue Technologies for Water Reuse: Current Status and Future Challenges)

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15 pages, 1265 KiB

Open AccessArticle

Supporter Profiling in Recycled Water Reuse: Evidence from Meta-Analysis

by Lingyan Li, Mimi Duan and Hanliang Fu

Water 2020, 12(10), 2735; https://doi.org/10.3390/w12102735 - 30 Sep 2020

Cited by 4 | Viewed by 2130

Abstract

Recycled water is considered as a viable alternative water source, and its use is of great significance in dealing with the shortage of water resources. However, it is often rejected by the public during its promotion. To identity the common social attributes of [...] Read more.

Recycled water is considered as a viable alternative water source, and its use is of great significance in dealing with the shortage of water resources. However, it is often rejected by the public during its promotion. To identity the common social attributes of proponents of recycled water, it is essential to study the profiled customers’ willingness to accept recycled water during the most difficult initial stage of promoting recycled water use projects. A meta-analysis was conducted in this study to deal with data concerning the influence of different social demographic factors on the public’s acceptance of recycled water use. Three steps of meta-analysis were mainly used in this paper. First, a random-effect model was used to measure the effect size of influencing factors, such as age, gender, and education. It was found that younger women were more likely to accept recycled water use than older men, and individuals with higher education were more willing to accept recycled water. Then, a cumulative meta-analysis showed that it was feasible to select young women with higher education as target profile customers in the initial stage of recycled water promotion. Finally, according to a meta-regression analysis, it was revealed that different research areas and selected model methods have important regulatory effects on the intention of the target population to use recycled water. Full article

(This article belongs to the Special Issue Technologies for Water Reuse: Current Status and Future Challenges)

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17 pages, 4877 KiB

Open AccessArticle

Yerba Mate (Ilex paraguarensis) as Bio-Adsorbent for the Removal of Methylene Blue, Remazol Brilliant Blue and Chromium Hexavalent: Thermodynamic and Kinetic Studies

by Leone Mazzeo, Irene Bavasso, Maria Paola Bracciale, Marco Cocchi, Luca Di Palma and Vincenzo Piemonte

Water 2020, 12(7), 2016; https://doi.org/10.3390/w12072016 - 16 Jul 2020

Cited by 8 | Viewed by 2546

Abstract

Yerba mate (Ilex paraguarensis, YM) was used as biomaterial for the removal of anionic and cationic compounds from wastewater. Chromium hexavalent Cr(VI), Remazol brilliant blue (RBB) and methylene blue (MB) were selected as pollutants. A calcination step was performed after the washing [...] Read more.

Yerba mate (Ilex paraguarensis, YM) was used as biomaterial for the removal of anionic and cationic compounds from wastewater. Chromium hexavalent Cr(VI), Remazol brilliant blue (RBB) and methylene blue (MB) were selected as pollutants. A calcination step was performed after the washing and drying steps to evaluate its effectiveness at increasing the adsorption capacity of the solid. Both YM and calcinated YM (CYM) were characterized by means of scanning electron microscopy (FE-SEM), Fourier transform infrared spectroscopy (FT-IR) and Brunauer–Emmett–Teller (BET) analysis. Adsorption batch tests revealed that YM was ineffective for the removal of Cr(VI) and RBB, while good results were obtained for MB (up to 80%) without pH dependency of the adsorption process, and CYM was able to remove Cr(VI) (up to 77%) and RBB (up to 65%) but not MB. The adsorption isotherm of MB on YM at 298 K was obtained experimentally and it is well represented by the Langmuir isotherm. YM’s adsorption capacity for MB was estimated to be 59.6 mg/g. Kinetic batch tests were conducted and the experimental results were fitted with a mathematical model. The low influence of temperature compared to the influence of the YM concentration on the adsorption rate was explained. Full article

(This article belongs to the Special Issue Technologies for Water Reuse: Current Status and Future Challenges)

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21 pages, 6438 KiB

Open AccessArticle

A Transport-Phenomena Approach to Model Hydrodynamic Cavitation of Organic Pollutants

by Mauro Capocelli, Carmen De Crescenzo, Despina Karatza, Amedeo Lancia, Dino Musmarra, Vincenzo Piemonte and Marina Prisciandaro

Water 2020, 12(6), 1564; https://doi.org/10.3390/w12061564 - 30 May 2020

Cited by 10 | Viewed by 2365

Abstract

Hydrodynamic cavitation (HC) has been extensively studied for the Advanced Oxidation of organic compounds in wastewaters since it physically produces an oxidative environment at ambient conditions. This process is simple and economical since it can be realized through a properly designed restriction in [...] Read more.

Hydrodynamic cavitation (HC) has been extensively studied for the Advanced Oxidation of organic compounds in wastewaters since it physically produces an oxidative environment at ambient conditions. This process is simple and economical since it can be realized through a properly designed restriction in a pipeline, even in retrofit solutions. Several experimental works individuated similar values of the optimal operating conditions, especially with regard to the inlet pressure. Up to now, the available modeling works rely on a single-bubble dynamics (SBD) approach and do not consider the actual process configuration and pollutant transport in proximity to the oxidizing environment. This work describes different experimental results (from this research group and others) and applies a novel mathematical model based on a transport-phenomena approach, able to directly simulate the effect of HC on the pollutant degradation. The novel proposed model is able to reproduce well a large number of experimental data obtained in different conditions, with different apparatus and different molecules, and allows to interconnect both SBD, fluid-dynamics, and physio-chemical variables in order to deeply study the interaction between the transport of pollutants and the reactive environment. This paper includes collection and discussion of several experimental results with the related main process parameters, description of the novel model and validation against the cited experimental results (to explain the effect of the operating pressure), sensitivity analysis, and the performance limit of the HC with the proposed modeling approach. Full article

(This article belongs to the Special Issue Technologies for Water Reuse: Current Status and Future Challenges)

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18 pages, 2803 KiB

Open AccessEditor’s ChoiceArticle

Reuse of Waste Geothermal Brine: Process, Thermodynamic and Economic Analysis

by Mauro Capocelli, Eugenio Moliterni, Vincenzo Piemonte and Marcello De Falco

Water 2020, 12(2), 316; https://doi.org/10.3390/w12020316 - 21 Jan 2020

Cited by 13 | Viewed by 4859

Abstract

Geothermal brines can be a resource of energy, freshwater and minerals. Even when rejected after their exploitation to produce energy in a power plant, the brines can be a source of freshwater and minerals, and can have a residual enthalpy that can be [...] Read more.

Geothermal brines can be a resource of energy, freshwater and minerals. Even when rejected after their exploitation to produce energy in a power plant, the brines can be a source of freshwater and minerals, and can have a residual enthalpy that can be recovered to produce additional power. The different reuse scenarios of these wasted brines depend on the composition and temperature at which they must be reinjected into the wells. On this basis, geothermal energy production is a perfect case study to investigate the water–energy nexus and to optimize the integrated energy- and water-production processes. In this paper, two case studies of brine reuse for both energy and water production are presented with the related process analysis, basic design and technical–economic analysis. A methodology to evaluate the exergy efficiency of the processes is presented by analyzing minimum work of separation, the maximum achievable work and the additional primary energy required for integrated production. The novel approach to estimate the process efficiency for integrated geothermal energy and desalination plants is applied to the case studies and discussed in light of literature results. Full article

(This article belongs to the Special Issue Technologies for Water Reuse: Current Status and Future Challenges)

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11 pages, 3048 KiB

Open AccessArticle

Reduction of Fouling and Scaling by Calcium Ions on an UF Membrane Surface for an Enhanced Water Pre-Treatment

by Marina Prisciandaro, Valentina Innocenzi, Francesco Tortora and Giuseppe Mazziotti di Celso

Water 2019, 11(5), 984; https://doi.org/10.3390/w11050984 - 10 May 2019

Cited by 9 | Viewed by 4682

Abstract

The control of fouling and scaling on heat and mass transfer surfaces is of major importance in processes as superficial water treatments, since it also improves the efficiency of the whole process from an energy saving point of view. The aim of the [...] Read more.

The control of fouling and scaling on heat and mass transfer surfaces is of major importance in processes as superficial water treatments, since it also improves the efficiency of the whole process from an energy saving point of view. The aim of the paper is to present the experimental results obtained in the inhibition of the fouling and scaling by calcium ions on an ultrafiltration membrane surface, by using citric acid as an additive. The last is an environmentally friendly additive−a so-called “green additive”, which may represent a reliable alternative to phosphorous and nitrogen based compounds typically used as inhibitors, since it has the characteristics of being non-toxic, non-bio accumulating, and biodegradable. The experimental plant is made of a tangential flow system on a lab scale equipped with a flat sheet ultrafiltration polymeric membrane, whose cut-off is 650 nm. In the first series of experiments, the effect of water hardness and its fouling effect due to calcium ions on membrane permeability has been measured in the range of potable waters. Then, the scaling effect of high calcium concentration in solution (supersaturated conditions) has been quantified by measuring the increase in weight of the membrane, with and without the addition of citric acid as an additive; moreover, the retarding effect of citric acid has been evaluated through the measurement of the induction times for the nucleation of calcium sulfate dihydrate (used as model scalant for fouling). Experiments have been carried out at two different supersaturation ratios (S = 2.25–2.60), at room temperature, in the absence of any additive, and with a citric acid concentration varying in the range 0.01 to 0.50 g/L. Experimental results have shown that the addition of citric acid in solution delays the induction times for gypsum crystals nucleation; moreover, it mitigates the phenomenon of membrane fouling and reduces the pressure drops by allowing an acceptable permeate flow for a longer duration. Full article

(This article belongs to the Special Issue Technologies for Water Reuse: Current Status and Future Challenges)

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12 pages, 2367 KiB

Open AccessFeature PaperArticle

Biological Treatment of Wastewater from Pyrolysis Plant: Effect of Organics Concentration, pH and Temperature

by Luca Di Palma, Irene Bavasso, Mauro Capocelli, Paolo De Filippis and Vincenzo Piemonte

Water 2019, 11(2), 336; https://doi.org/10.3390/w11020336 - 16 Feb 2019

Cited by 7 | Viewed by 3416

Abstract

The biological treatment of the aqueous residue produced during poplar wood pyrolysis was investigated. The biological treatment experiments were carried out at two different pH conditions (controlled at 7, uncontrolled) in batch mode at three different temperatures (15 °C, 25 °C and 30 [...] Read more.

The biological treatment of the aqueous residue produced during poplar wood pyrolysis was investigated. The biological treatment experiments were carried out at two different pH conditions (controlled at 7, uncontrolled) in batch mode at three different temperatures (15 °C, 25 °C and 30 °C) and initial total organic carbon of the water ranging from 800 mg/L to 2800 mg/L. Results show that a substantial removal of organic carbon could be achieved in aerobic conditions after biomass acclimation. After 72 h of treatment, total organic carbon (TOC) removal mean values of 49.47% and 53.03% were observed at 30 °C for solution at 1400 and 2000 mg/L initial TOC, respectively. In the case of 1400 mg/L, a further mineralization (61.80%) was achieved during 144 h of treatment, by using a two-step process. A kinetic study of the process was also made, showing that organics mineralization followed a first-order kinetic model. Full article

(This article belongs to the Special Issue Technologies for Water Reuse: Current Status and Future Challenges)

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