Advances in Water and Wastewater Monitoring and Treatment Technology

A special issue of Water (ISSN 2073-4441). This special issue belongs to the section "Wastewater Treatment and Reuse".

Deadline for manuscript submissions: closed (30 October 2019) | Viewed by 68347

Special Issue Editors

Department of Environmental Engineering, INHA University, Incheon 22212, Korea
Interests: advanced oxidation processes; photocatalysis; toxins; contaminants of emerging concern; nutrients recovery; water treatment
Special Issues, Collections and Topics in MDPI journals
Departmento de Ingeniería Agrícola y Forestal, Universidad de Valladolid, 47002 Valladolid, Spain
Interests: water treatment; water management; advanced oxidation processes; photocatalysis; membranes; physico-chemical processes; biological treatment; clean technologies; energy and water use; sustainable production
Special Issues, Collections and Topics in MDPI journals
United States Environmental Protection Agency (US EPA), 26 West Martin Luther King Drive, Cincinnati, OH 45268, USA
Interests: health-related water microbiology: Physical removal and inactivation of waterborne pathogens and rapid detection of infectious microorganisms; microbial ecology: Development of microbial source tracking markers and microbial community characterization; sustainable energy saving biological treatment processes: Microbial electrochemical (MEC) technologies
Special Issues, Collections and Topics in MDPI journals
Department of Earth and Environmental Studies, Montclair State University, Montclair, New Jersey, USA
Interests: innovative water treatment and reuse technologies; sustainable stormwater treatment; landfill leachate treatment and management

Special Issue Information

Dear Colleagues,

Water contamination, water treatment and water resource management are topics of great interest nowadays, due to the adverse effects that contaminated water produce with respect to the environment and human health; and sanitary problems as a result of insufficient clean portable water. Furthermore, it is essential to increase knowledge regarding the monitoring and control of water quality due to the presence of different priorities and emerging contaminants and to develop innovative water and wastewater treatment technologies. As a consequence, we will focus this Special Issue on the current stage of technologies to monitor, control and remove pollutants in water and wastewater.

Dr. Changseok Han
Prof. Daphne Hermosilla Redondo
Dr. Hodon Ryu
Prof. Yang Deng
Guest Editors

Manuscript Submission Information

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Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Water is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • Water and Wastewater Treatment
  • Contaminants of Emerging Concern and Priority Pollutants
  • Monitoring of Water

Published Papers (17 papers)

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Research

10 pages, 3038 KiB  
Article
Bifunctional g-C3N4/WO3 Thin Films for Photocatalytic Water Purification
by Maria Antoniadou, Michalis K. Arfanis, Islam Ibrahim and Polycarpos Falaras
Water 2019, 11(12), 2439; https://doi.org/10.3390/w11122439 - 21 Nov 2019
Cited by 33 | Viewed by 4929
Abstract
A bifunctional thin film photocatalyst consisting of graphitic carbon nitride on tungsten trioxide (g-C3N4/WO3) is introduced for the improvement of photocatalytic activity concerning hexavalent chromium reduction and methylene blue dye removal in water, compared to the bare, [...] Read more.
A bifunctional thin film photocatalyst consisting of graphitic carbon nitride on tungsten trioxide (g-C3N4/WO3) is introduced for the improvement of photocatalytic activity concerning hexavalent chromium reduction and methylene blue dye removal in water, compared to the bare, widely used WO3 semiconductor. A bilayered structure was formed, which is important for the enhancement of the charge carriers’ separation. The characterization of morphological, structural, optoelectronic, and vibrational properties of the photocatalysts permitted a better understanding of their photocatalytic activity for both dye degradation and Cr+6 elimination in water and the analysis of the photocatalytic kinetics permitted the determination of the corresponding pseudo-first-order reaction constants (k). Trapping experiments performed under UV illumination revealed that the main active species for the photocatalytic reduction of Cr+6 ions are electrons, whereas in the case of methylene blue azo-dye (MB) oxidation, the activation of the corresponding photocatalytic degradation comes via both holes and superoxide radicals. Full article
(This article belongs to the Special Issue Advances in Water and Wastewater Monitoring and Treatment Technology)
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17 pages, 4096 KiB  
Article
Activated Carbon and the Principal Mineral Constituents of a Natural Soil in the Presence of Carbamazepine
by Mohamed BIZI
Water 2019, 11(11), 2290; https://doi.org/10.3390/w11112290 - 31 Oct 2019
Cited by 17 | Viewed by 3651
Abstract
The presence of pharmaceutical residues in the different aquatic compartments is a major environmental issue. Carbamazepine (CBZ), a heterocyclic antiepileptic, which is neutral between pH 3 and 11, is known to resist biodegradation. Its elimination in wastewater treatment plants is below 20% regardless [...] Read more.
The presence of pharmaceutical residues in the different aquatic compartments is a major environmental issue. Carbamazepine (CBZ), a heterocyclic antiepileptic, which is neutral between pH 3 and 11, is known to resist biodegradation. Its elimination in wastewater treatment plants is below 20% regardless of the primary and/or secondary treatments currently implemented. Its presence in groundwater raises questions about soil permeability in relation to this molecule. In order to provide meaningful answers, the CBZ adsorption performances of the principal mineral constituents of a natural soil (alumina, quartz, goethite, haematite, kaolinite, montmorillonite, and a saponin stevensite) and of an industrial activated carbon were assessed. Prior to the batch adsorption tests, the texture, mineralogy, and zero point of charge of these products were determined. X-ray diffraction (XRD) and UV-visible spectrometry were used to characterize the CBZ used. With the exception of stevensite, these minerals did not adsorb CBZ. However, stevensite’s affinity for CBZ remained very low compared to that of activated carbon (235 mg/g, tap water), which proved to be the most appropriate product for eliminating CBZ. The π−π, CH−π, and hydrogen bonds are the basis for the interactions established between CBZ and activated carbon, and their combination increases the overall adsorption efficiency. Full article
(This article belongs to the Special Issue Advances in Water and Wastewater Monitoring and Treatment Technology)
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13 pages, 1965 KiB  
Article
Release of Ag/ZnO Nanomaterials and Associated Risks of a Novel Water Sterilization Technology
by Chengfang Pang, Aiga Mackevica, Jingjing Tian, Hongqing Feng, Zhou Li and Anders Baun
Water 2019, 11(11), 2276; https://doi.org/10.3390/w11112276 - 30 Oct 2019
Cited by 3 | Viewed by 2716
Abstract
For water sterilization, a highly effective system utilizing electrophoresis and the antimicrobial properties of Ag/ZnO nanomaterials has been developed. However, the key component of this system, a sterilization carbon cloth containing Ag/ZnO nanomaterials, has not been evaluated with respect to the potential environmental [...] Read more.
For water sterilization, a highly effective system utilizing electrophoresis and the antimicrobial properties of Ag/ZnO nanomaterials has been developed. However, the key component of this system, a sterilization carbon cloth containing Ag/ZnO nanomaterials, has not been evaluated with respect to the potential environmental and human health risks associated with the nanomaterials released. In this paper, a recirculation flow system and methodology were developed to study the release of Ag and ZnO during water treatment. Our study showed that the released silver nanoparticles and dissolved Ag from the carbon cloth were 50 µg/L and 143 µg/L in the United States Environmental Protection Agency (EPA) medium, respectively. The release of dissolved Zn in the EPA medium was 33 µg /L. The results indicate that the release of dissolved and nanoparticulate silver from the sterilization carbon cloth exceeded acceptable risk levels in the aquatic environment. However, if the sterilization carbon cloth was pre-washed two days prior to use, the concentration of Ag was below the drinking water limit of 0.1 mg/L. Our study provides important exposure data for a novel water sanitation technology for real-world application in waste water and drinking water treatment, and aid in assuring its safe use. Full article
(This article belongs to the Special Issue Advances in Water and Wastewater Monitoring and Treatment Technology)
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15 pages, 2583 KiB  
Article
Advanced Oxidation Based Treatment of Soil Wash Water Contaminated with Sulfolane
by Mariana Brandão, Linlong Yu, Carlos Garcia and Gopal Achari
Water 2019, 11(10), 2152; https://doi.org/10.3390/w11102152 - 16 Oct 2019
Cited by 13 | Viewed by 3194
Abstract
This study investigates advanced oxidation processes (AOPs) as post-treatment techniques to degrade sulfolane in soil washing water. Soil washing experiments were conducted with different soil/water ratios, shaking times, and number of extraction cycles. The soil wash water containing sulfolane was treated with four [...] Read more.
This study investigates advanced oxidation processes (AOPs) as post-treatment techniques to degrade sulfolane in soil washing water. Soil washing experiments were conducted with different soil/water ratios, shaking times, and number of extraction cycles. The soil wash water containing sulfolane was treated with four AOPs including H2O2/ultraviolet (UV), O3/UV, alkaline ozonation, and neutral Fenton reagent. Results show that sulfolane can be effectively removed from the soil using water as a washing solvent, where optimum conditions were found with 30 min of vigorous shaking, using 1:2 soil/water mass ratio, and a three-cycle extraction procedure. Moreover, the sulfolane in the soil wash water was also effectively degraded using appropriate AOPs. Among the four AOPs investigated, neutral Fenton was the least effective method to treat sulfolane in the wash water, while H2O2/UV, O3/UV, and alkaline ozonation can achieve more than 99% of sulfolane degradation within 1 h. Full article
(This article belongs to the Special Issue Advances in Water and Wastewater Monitoring and Treatment Technology)
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12 pages, 3181 KiB  
Article
Electrospun Nylon 6,6/ZIF-8 Nanofiber Membrane for Produced Water Filtration
by Nur Syakinah Abd Halim, Mohd Dzul Hakim Wirzal, Muhammad Roil Bilad, Nik Abdul Hadi Md Nordin, Zulfan Adi Putra, Abdull Rahim Mohd Yusoff, Thanitporn Narkkun and Kajornsak Faungnawakij
Water 2019, 11(10), 2111; https://doi.org/10.3390/w11102111 - 11 Oct 2019
Cited by 16 | Viewed by 4072
Abstract
This study develops electrospun nylon 6,6 nanofiber membrane (NFM), incorporating zeolitic imidazolate framework-8 (ZIF-8) as the additive for produced water (PW) filtration. Electrospun NFM is suitable to be used as a filter, especially for water treatment, since it has a huge surface area [...] Read more.
This study develops electrospun nylon 6,6 nanofiber membrane (NFM), incorporating zeolitic imidazolate framework-8 (ZIF-8) as the additive for produced water (PW) filtration. Electrospun NFM is suitable to be used as a filter, especially for water treatment, since it has a huge surface area to volume ratio, high porosity, and great permeability compared to the conventional membranes. These properties also enhance its competitiveness to be used as reverse osmosis pre-treatment, as the final stage of PW treatment water reuse purpose. However, the fouling issue and low mechanical strength of NFM reduces hydraulic performance over time. Therefore, this study employs ZIF-8 as an additive to improve nylon 6,6 NFM properties to reduce fouling and increase membrane tensile strength. Results show that the optimum loading of ZIF-8 was at 0.2%. This loading gives the highest oil rejection (89%), highest steady-state pure water permeability (1967 L/(m2·h·bar)), 2× higher than untreated nylon 6,6 NFM with tensile strength 5× greater (3743 MPa), and a steady-state permeability of 1667 L/(m2·h·bar) for filtration of real produced water. Full article
(This article belongs to the Special Issue Advances in Water and Wastewater Monitoring and Treatment Technology)
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17 pages, 792 KiB  
Article
Treatment of a Mature Landfill Leachate: Comparison between Homogeneous and Heterogeneous Photo-Fenton with Different Pretreatments
by Javier Tejera, Ruben Miranda, Daphne Hermosilla, Iñigo Urra, Carlos Negro and Ángeles Blanco
Water 2019, 11(9), 1849; https://doi.org/10.3390/w11091849 - 05 Sep 2019
Cited by 53 | Viewed by 4404
Abstract
This study focuses on the treatment of a mature landfill leachate by coagulation and photo-Fenton at different conditions. Optimal coagulation is carried out with ferric chloride in acid conditions; and with alum in near-neutral conditions, to minimize the use of sulphuric acid for [...] Read more.
This study focuses on the treatment of a mature landfill leachate by coagulation and photo-Fenton at different conditions. Optimal coagulation is carried out with ferric chloride in acid conditions; and with alum in near-neutral conditions, to minimize the use of sulphuric acid for pH adjustment (1 g/L vs. 7.2 g/L), the generation of sludge and the increase of conductivity in the final effluent. In both cases, a similar chemical oxygen demand (COD) removal is obtained, higher than 65%, which is high enough for a subsequent photo-Fenton treatment. However, the removal of absorbance at 254 nm (UV-254) was significantly higher with ferric chloride (83% vs. 55%), due to the important removal of humic acids at acid pH. The best results for coagulation are 2 g/L ferric chloride at initial pH = 5 and 5 g/L alum at initial pH = 7. After coagulation with ferric chloride, the final pH (2.8) is adequate for a homogeneous photo-Fenton using the remaining dissolved iron (250 mg/L). At these conditions, using a ratio H2O2/COD = 2.125 and 30 min contact time, the biodegradability increased from 0.03 to 0.51. On the other hand, the neutral pH after alum coagulation (6.7) allows the use of zero valent iron (ZVI) heterogeneous photo-Fenton. In this case, a final biodegradability of 0.32 was obtained, after 150 min, using the same H2O2/COD ratio. Both treatments achieved similar results, with a final COD, UV-254 and color removal greater than 90%. However, the economic assessment shows that the approach of ferric chloride + homogeneous photo-Fenton is much cheaper (6.4 €/m3 vs. 28.4 €/m3). Although the discharge limits are not achieved with the proposed combination of treatments, the significant increase of the pre-treated leachate biodegradability allows achieving the discharge limits after a conventional biological treatment such as sequencing batch reactor, which would slightly increase the total treatment cost. Full article
(This article belongs to the Special Issue Advances in Water and Wastewater Monitoring and Treatment Technology)
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11 pages, 2509 KiB  
Article
Scaling up Microbial Fuel Cells for Treating Swine Wastewater
by Yuko Goto and Naoko Yoshida
Water 2019, 11(9), 1803; https://doi.org/10.3390/w11091803 - 29 Aug 2019
Cited by 34 | Viewed by 5409
Abstract
Conventional aerobic treatment of swine wastewater, which generally contains 4500–8200 mg L−1 of organic matter, is energy-consuming. The aim of this study was to assess the application of scaled-up microbial fuel cells (MFCs) with different capacities (i.e., 1.5 L, 12 L, and [...] Read more.
Conventional aerobic treatment of swine wastewater, which generally contains 4500–8200 mg L−1 of organic matter, is energy-consuming. The aim of this study was to assess the application of scaled-up microbial fuel cells (MFCs) with different capacities (i.e., 1.5 L, 12 L, and 100 L) for removing organic matter from swine wastewater. The MFCs were single-chambered, consisting of an anode of microbially reduced graphene oxide (rGO) and an air-cathode of platinum-coated carbon cloth. The MFCs were polarized via an external resistance of 3–10 Ω for 40 days for the 1.5 L-MFC and 120 days for the 12L- and 100 L-MFC. The MFCs were operated in continuous flow mode (hydraulic retention time: 3–5 days). The 100 L-MFC achieved an average chemical oxygen demand (COD) removal efficiency of 52%, which corresponded to a COD removal rate of 530 mg L−1 d−1. Moreover, the 100 L-MFC showed an average and maximum electricity generation of 0.6 and 2.2 Wh m−3, respectively. Our findings suggest that MFCs can effectively be used for swine wastewater treatment coupled with the simultaneous generation of electricity. Full article
(This article belongs to the Special Issue Advances in Water and Wastewater Monitoring and Treatment Technology)
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13 pages, 3988 KiB  
Article
Sulfate Radicals-Based Technology as a Promising Strategy for Wastewater
by María Arellano, Marta Pazos and María Ángeles Sanromán
Water 2019, 11(8), 1695; https://doi.org/10.3390/w11081695 - 15 Aug 2019
Cited by 10 | Viewed by 3075
Abstract
This study was focused on the generation of sulfate radicals and their applicability as powerful oxidants for degrading complex organic compounds with the final objective of operating in flow systems. To this end, the removal of two compounds from the pharmaceutical industry was [...] Read more.
This study was focused on the generation of sulfate radicals and their applicability as powerful oxidants for degrading complex organic compounds with the final objective of operating in flow systems. To this end, the removal of two compounds from the pharmaceutical industry was assessed, lissamine green and prednisolone. Initially, sulfate radicals were generated by the activation of persulfate with iron as homogenous catalyst, and the key parameters involved in the process, as catalyst concentration and oxidant dosage, were evaluated. Furthermore, with the aim of preventing the secondary contamination due to metal leaching and to be operate in a continuous mode, a heterogeneous catalyst was developed. For it, the iron was fixed on a cationic resin as Amberlite IR120 Na+ form. It was demonstrated that the removal of both pollutants increases with greater catalyst dosages, achieving a decay of 85% within 25 min with 30 g·L−1 of catalyst. Moreover, the reuse capability of the catalyst was tested, illustrating that it is rough enough for its reuse. Conversely, in order to develop a continuous treatment in flow system, a fixed bed reactor was constructed and its feasibility was proven. Different experiments with residence times from 10 min to 60 min were performed, obtaining a removal level of ≈95% and 90% for prednisolone and lissamine green, respectively, at residence time of 60 min. In conclusion, the potential of sulfate radicals-based technology for degrading organic contaminants has been demonstrated. Full article
(This article belongs to the Special Issue Advances in Water and Wastewater Monitoring and Treatment Technology)
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14 pages, 1504 KiB  
Article
Use of Visible Light Modulation Techniques in Urea Photocatalytic Degradation
by Vincenzo Vaiano, Olga Sacco, Giulia Di Capua, Nicola Femia and Diana Sannino
Water 2019, 11(8), 1642; https://doi.org/10.3390/w11081642 - 08 Aug 2019
Cited by 12 | Viewed by 3749
Abstract
The aim of this work was to analyze the effect of visible LED dimming duty-cycle modulation techniques in a photocatalytic system for urea degradation using a visible light photocatalyst immobilized on macroscopic supports. For this reason, the effect of different LED dimming techniques [...] Read more.
The aim of this work was to analyze the effect of visible LED dimming duty-cycle modulation techniques in a photocatalytic system for urea degradation using a visible light photocatalyst immobilized on macroscopic supports. For this reason, the effect of different LED dimming techniques was investigated and compared in terms of urea degradation together with ammonia and nitrate production during the irradiation time. The experimental results evidenced that using a visible LED dimming modulation with variable-peak variable-duty pulse-width modulation (PWM) allows to improve the photocatalytic degradation process, with respect to classical LED dimming with fixed-peak fixed-duty PWM, and influences the product’s distribution of ammonia and nitrate in water. Therefore, the proof of concept herein proposed could be considered as preliminary potential results to be used in water recycling applications with a particular emphasis in recovery of urea photodegradation byproducts, such as ammonia, from wastewater that could be used as potential resources and an energy resource. Full article
(This article belongs to the Special Issue Advances in Water and Wastewater Monitoring and Treatment Technology)
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22 pages, 1993 KiB  
Article
Advanced Supervisory Control System Implemented at Full-Scale WWTP—A Case Study of Optimization and Energy Balance Improvement
by Jakub Drewnowski
Water 2019, 11(6), 1218; https://doi.org/10.3390/w11061218 - 11 Jun 2019
Cited by 14 | Viewed by 3649
Abstract
In modern and cost-effective Wastewater Treatment Plants (WWTPs), processes such as aeration, chemical feeds and sludge pumping are usually controlled by an operating system integrated with online sensors. The proper verification of these data-driven measurements and the control of different unit operations at [...] Read more.
In modern and cost-effective Wastewater Treatment Plants (WWTPs), processes such as aeration, chemical feeds and sludge pumping are usually controlled by an operating system integrated with online sensors. The proper verification of these data-driven measurements and the control of different unit operations at the same time has a strong influence on better understanding and accurately optimizing the biochemical processes at WWTP—especially energy-intensive biological parts (e.g., the nitrification zone/aeration system and denitrification zone/internal recirculation). In this study, by integrating a new powerful PreviSys with data driven from the Supervisory Control and Data Acquisition (SCADA) software and advanced algorithms such as Model Predictive Control (MPC) by using the WEST computer platform, it was possible to conduct different operation strategies for optimizing and improving the energy balance at a full-scale “Klimzowiec” WWTP located in Chorzow (Southern Poland). Moreover, the novel concept of double-checking online data-driven measurements (from installed DO, NO3, NH4 sensors, etc.) by mathematical modelling and computer simulation predictions was applied in order to check the data uncertainty and develop a support operator system (SOS)—an additional tool for the widely-used in-operation and control of modern and cost-effective WWTPs. The results showed that by using sophisticated PreviSys technology, a better understanding and accurate optimization of biochemical processes, as well as more sustainable WWTP operation, can be achieved. Full article
(This article belongs to the Special Issue Advances in Water and Wastewater Monitoring and Treatment Technology)
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8 pages, 970 KiB  
Communication
Efficacy of Inactivation of Human Enteroviruses by Dual-Wavelength Germicidal Ultraviolet (UV-C) Light Emitting Diodes (LEDs)
by Hyoungmin Woo, Sara E. Beck, Laura A. Boczek, Kelsie M. Carlson, Nichole E. Brinkman, Karl G. Linden, Oliver R. Lawal, Samuel L. Hayes and Hodon Ryu
Water 2019, 11(6), 1131; https://doi.org/10.3390/w11061131 - 30 May 2019
Cited by 30 | Viewed by 4717
Abstract
The efficacy of germicidal ultraviolet (UV-C) light emitting diodes (LEDs) was evaluated for inactivating human enteroviruses included on the United States Environmental Protection Agency (EPA)’s Contaminant Candidate List (CCL). A UV-C LED device, emitting at peaks of 260 nm and 280 nm and [...] Read more.
The efficacy of germicidal ultraviolet (UV-C) light emitting diodes (LEDs) was evaluated for inactivating human enteroviruses included on the United States Environmental Protection Agency (EPA)’s Contaminant Candidate List (CCL). A UV-C LED device, emitting at peaks of 260 nm and 280 nm and the combination of 260/280 nm together, was used to measure and compare potential synergistic effects of dual wavelengths for disinfecting viral organisms. The 260 nm LED proved to be the most effective at inactivating the CCL enteroviruses tested. To obtain 2-log10 inactivation credit for the 260 nm LED, the fluences (UV doses) required are approximately 8 mJ/cm2 for coxsackievirus A10 and poliovirus 1, 10 mJ/cm2 for enterovirus 70, and 13 mJ/cm2 for echovirus 30. No synergistic effect was detected when evaluating the log inactivation of enteroviruses irradiated by the dual-wavelength UV-C LEDs. Full article
(This article belongs to the Special Issue Advances in Water and Wastewater Monitoring and Treatment Technology)
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18 pages, 3664 KiB  
Article
Intelligent Control/Operational Strategies in WWTPs through an Integrated Q-Learning Algorithm with ASM2d-Guided Reward
by Jiwei Pang, Shanshan Yang, Lei He, Yidi Chen and Nanqi Ren
Water 2019, 11(5), 927; https://doi.org/10.3390/w11050927 - 01 May 2019
Cited by 23 | Viewed by 3778
Abstract
The operation of a wastewater treatment plant (WWTP) is a typical complex control problem, with nonlinear dynamics and coupling effects among the variables, which renders the implementation of real-time optimal control an enormous challenge. In this study, a Q-learning algorithm with activated sludge [...] Read more.
The operation of a wastewater treatment plant (WWTP) is a typical complex control problem, with nonlinear dynamics and coupling effects among the variables, which renders the implementation of real-time optimal control an enormous challenge. In this study, a Q-learning algorithm with activated sludge model No. 2d-guided (ASM2d-guided) reward setting (an integrated ASM2d-QL algorithm) is proposed, and the widely applied anaerobic-anoxic-oxic (AAO) system is chosen as the research paradigm. The integrated ASM2d-QL algorithms equipped with a self-learning mechanism are derived for optimizing the control strategies (hydraulic retention time (HRT) and internal recycling ratio (IRR)) of the AAO system. To optimize the control strategies of the AAO system under varying influent loads, Q matrixes were built for both HRTs and IRR optimization through the pair of <max reward-action> based on the integrated ASM2d-QL algorithm. 8 days of actual influent qualities of a certain municipal AAO wastewater treatment plant in June were arbitrarily chosen as the influent concentrations for model verification. Good agreement between the values of the model simulations and experimental results indicated that this proposed integrated ASM2d-QL algorithm performed properly and successfully realized intelligent modeling and stable optimal control strategies under fluctuating influent loads during wastewater treatment. Full article
(This article belongs to the Special Issue Advances in Water and Wastewater Monitoring and Treatment Technology)
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17 pages, 1595 KiB  
Article
Application of the Mathematical Simulation Methods for the Assessment of the Wastewater Treatment Plant Operation Work Reliability
by Dariusz Młyński, Piotr Bugajski and Anna Młyńska
Water 2019, 11(5), 873; https://doi.org/10.3390/w11050873 - 26 Apr 2019
Cited by 13 | Viewed by 4185
Abstract
The aim of the present work was the modeling of the wastewater treatment plant operation work using Monte Carlo method and different random variables probability distributions modeling. The analysis includes the following pollutants indicators; BOD5 (Biochemical Oxygen Demand), CODCr (Chemical Oxygen [...] Read more.
The aim of the present work was the modeling of the wastewater treatment plant operation work using Monte Carlo method and different random variables probability distributions modeling. The analysis includes the following pollutants indicators; BOD5 (Biochemical Oxygen Demand), CODCr (Chemical Oxygen Demand), Total Suspended Solids (SSt), Total Nitrogen (TN), and Total Phosphorus (TP). The Anderson–Darling (A–D) test was used for the assessment of theoretical and empirical distributions compatibility. The selection of the best-fitting statistical distributions was performed using peak-weighted root mean square (PWRMSE) parameter. Based on the performed calculations, it was stated that pollutants indicators in treated sewage were characterized by a significant variability. Obtained results indicate that the best-fitting pollutants indicators statistical distribution is Gauss Mixed Model (GMM) function. The results of the Monte Carlo simulation method confirmed that some problems related to the organic and biogenic pollutants reduction may be observed in the Wastewater Treatment Plant, in Jaworzno. Full article
(This article belongs to the Special Issue Advances in Water and Wastewater Monitoring and Treatment Technology)
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17 pages, 8941 KiB  
Article
Diethylene Glycol-Assisted Organized TiO2 Nanostructures for Photocatalytic Wastewater Treatment Ceramic Membranes
by Rizwan Ahmad, Jin Kyu Kim, Jong Hak Kim and Jeonghwan Kim
Water 2019, 11(4), 750; https://doi.org/10.3390/w11040750 - 10 Apr 2019
Cited by 9 | Viewed by 3925
Abstract
A high-performance photocatalytic ceramic membrane was developed by direct growth of a TiO2 structure on a macroporous alumina support using a hydrothermal method. The morphological nanostructure of TiO2 on the support was successfully controlled via the interaction between the TiO2 [...] Read more.
A high-performance photocatalytic ceramic membrane was developed by direct growth of a TiO2 structure on a macroporous alumina support using a hydrothermal method. The morphological nanostructure of TiO2 on the support was successfully controlled via the interaction between the TiO2 precursor and a capping agent, diethylene glycol (DEG). The growth of anatase TiO2 nanorods was observed both on the membrane surface and pore walls. The well-organized nanorods TiO2 reduced the perturbation of the alumina support, thus controlling the hydrolysis rate of the TiO2 precursor and reducing membrane fouling. However, a decrease in the amount of the DEG capping agent significantly reduced membrane permeability, owing to the formation of nonporous clusters of TiO2 on the support. Distribution of the organized TiO2 nanorods on the support was very effective for the improvement of the organic removal efficiency and antifouling under ultraviolet illumination. The TiO2 nanostructure associated with the reactive crystalline phase, rather than the amount of layered TiO2 formed on the support, which was found to be the key to controlling photocatalytic membrane reactivity. These experimental findings would provide a new approach for the development of efficacious photocatalytic membranes with improved performance for wastewater treatment. Full article
(This article belongs to the Special Issue Advances in Water and Wastewater Monitoring and Treatment Technology)
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13 pages, 400 KiB  
Article
Feed Spacer Geometries and Permeability Coefficients. Effect on the Performance in BWRO Spriral-Wound Membrane Modules
by Alejandro Ruiz-García and Ignacio de la Nuez Pestana
Water 2019, 11(1), 152; https://doi.org/10.3390/w11010152 - 16 Jan 2019
Cited by 46 | Viewed by 5215
Abstract
Reverse osmosis (RO) is the most widely used technology to desalinate brackish water and seawater. Significant efforts have been made in recent decades to improve RO efficiency. Feed spacer geometry design is a very important factor in RO membrane performance. In this work, [...] Read more.
Reverse osmosis (RO) is the most widely used technology to desalinate brackish water and seawater. Significant efforts have been made in recent decades to improve RO efficiency. Feed spacer geometry design is a very important factor in RO membrane performance. In this work, correlations based on computational fluid dynamics and experimental work were applied in an algorithm to simulate the effect of different feed spacer geometries in full-scale brackish water reverse osmosis (BWRO) membranes with different permeability coefficients. The aim of this work was to evaluate the impact of feed spacers in conjunction with the permeability coefficients on membrane performance. The results showed a greater impact of feed spacer geometries in the membrane with the highest water permeability coefficient (A). Studying only one single element in a series, variations due to feed spacer geometries were observed in specific energy consumption ( S E C ) and permeate concentration ( C p ) of about 6.83% and 10.42%, respectively. Allowing the rolling of commercial membranes with different feed spacer geometries depending on the operating conditions could optimize the RO process. Full article
(This article belongs to the Special Issue Advances in Water and Wastewater Monitoring and Treatment Technology)
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17 pages, 1444 KiB  
Article
Multilevel Adaptive Control of Alternating Aeration Cycles in Wastewater Treatment to Improve Nitrogen and Phosphorous Removal and to Obtain Energy Saving
by Pedro T. Martín de la Vega and Miguel A. Jaramillo-Morán
Water 2019, 11(1), 60; https://doi.org/10.3390/w11010060 - 31 Dec 2018
Cited by 4 | Viewed by 3097
Abstract
This work presents an adaptive control of the process of alternating aeration/non-aeration cycles for wastewater treatment. It is aimed at improving nitrogen and phosphorous removal efficiency and reducing energy consumption. It comprises two control levels. The first decides when to switch on and [...] Read more.
This work presents an adaptive control of the process of alternating aeration/non-aeration cycles for wastewater treatment. It is aimed at improving nitrogen and phosphorous removal efficiency and reducing energy consumption. It comprises two control levels. The first decides when to switch on and off aeration by comparing the Dissolved Oxygen (DO) and the Oxidation Reduction Potential (ORP) with two activation thresholds. The second, a supervisory control, continuously adapt their values by analyzing the working conditions of the reactor (organic matter and ammonium loads). These working conditions are described by four parameters obtained from the DO and ORP curves: Oxygen Uptake Rate (OUR), Oxygen Rise Average Slope (ORAS), ORParrow and Nitrate and Oxygen Uptake Rate (NOUR). It also adjusts the aeration system power to adapt it to those conditions. This adaptive control has been implemented in a laboratory scale prototype and its performance compared with that provided by another control with fixed thresholds and aeration power implemented in a similar prototype. The adaptive control clearly outperforms that without adaptation in nitrogen and phosphorous removal efficiency and requires lower energy consumption. Similar efficiencies were obtained for organic matter removal (higher than 90% in both cases). Full article
(This article belongs to the Special Issue Advances in Water and Wastewater Monitoring and Treatment Technology)
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13 pages, 6088 KiB  
Article
Barium-Encapsulated Biodegradable Polycaprolactone for Sulfate Removal
by Changseok Han and Mallikarjuna N. Nadagouda
Water 2018, 10(12), 1789; https://doi.org/10.3390/w10121789 - 06 Dec 2018
Viewed by 3298
Abstract
Various compositions of barium carbonate (BaCO3) loaded polycaprolactone (PCL) composites were prepared, including 2.5/97.5, 10/90, 30/70, 50/50 and 90/10 (PCL/BaCO3), via re-precipitation technique. Small-scale column tests were conducted to study the efficiency of sulfate removal using the PCL/BaCO3 [...] Read more.
Various compositions of barium carbonate (BaCO3) loaded polycaprolactone (PCL) composites were prepared, including 2.5/97.5, 10/90, 30/70, 50/50 and 90/10 (PCL/BaCO3), via re-precipitation technique. Small-scale column tests were conducted to study the efficiency of sulfate removal using the PCL/BaCO3 composites. The composites before and after their use to remove sulfate were extensively characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), transmission electron microscopy (TEM), high-resolution TEM (HR-TEM), and thermogravimetric analysis (TGA). As PCL is a biodegradable polymer, these composites are environmentally friendly and have several advantages over barium sulfate precipitation in overcoming clogging issues in filters or resins due to collection of natural organic matter (NOM). The media used in this study exhibited high capacity and was able to remove more than 90% sulfate from synthetic sulfate containing waters and NOM samples collected from the Ohio River. Full article
(This article belongs to the Special Issue Advances in Water and Wastewater Monitoring and Treatment Technology)
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