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Sun F, Chen J, Sun Z, Zheng X, Tang M, Yang Y. Promoting bioremediation of brewery wastewater, production of bioelectricity and microbial community shift by sludge microbial fuel cells using biochar as anode. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 929:172418. [PMID: 38631622 DOI: 10.1016/j.scitotenv.2024.172418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2024] [Revised: 03/31/2024] [Accepted: 04/10/2024] [Indexed: 04/19/2024]
Abstract
Seeking low-cost and eco-friendly electrode catalyst of microbial fuel cell (MFC) reactor has received extensive attention in recent decades. In this study, a sludge MFC was coupled with biochar-modified-anode (BC-300, BC-400, and BC-500) for actual brewery wastewater treatment. The physicochemical properties of biochar largely depended on the pyrolysis temperature, further affecting the removal efficiency of wastewater indicators. BC-400 MFC proved to be efficient for TN and NH4+-N removal, while the maximum removal efficiencies of COD and TP were achieved by BC-500 MFC, reaching respectively 97.14 % and 89.67 %. Biochar could promote the degradation of dissolved organic matter (DOM) in wastewater by increasing the electrochemical performances of MFC. The maximum output voltage of BC-400 MFC reached 410.24 mV, and the maximum electricity generation of 108.05 mW/m2 was also obtained, surpassing the pristine MFC (BCC-MFC) by 4.67 times. High-throughput sequencing results illustrated that the enrichment of electrochemically active bacteria (EAB) and functional bacteria (Longilinea, Denitratisoma, and Pseudomonas) in BC-MFCs, contributed to pollutants degradation and electron transfer. Furthermore, biochar affected directly the electrical conductivity of wastewater, simultaneously changing microbial community composition of MFC anode. Considering both enhanced removal efficiency of pollutants and increased power generation, the results of this study would offer technical reference for the application of biochar as MFC catalyst for brewery wastewater treatment.
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Affiliation(s)
- Fengfei Sun
- School of Life Sciences, Qufu Normal University, Qufu 273165, PR China
| | - Junfeng Chen
- School of Life Sciences, Qufu Normal University, Qufu 273165, PR China.
| | - Ziren Sun
- School of Life Sciences, Qufu Normal University, Qufu 273165, PR China
| | - Xingjia Zheng
- School of Life Sciences, Qufu Normal University, Qufu 273165, PR China
| | - Meizhen Tang
- School of Life Sciences, Qufu Normal University, Qufu 273165, PR China
| | - Yuewei Yang
- School of Life Sciences, Qufu Normal University, Qufu 273165, PR China.
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Durna Pişkin E, Genç N. Multi response optimization of waste activated sludge oxidation and azo dye reduction in microbial fuel cell. ENVIRONMENTAL TECHNOLOGY 2024; 45:2599-2611. [PMID: 36762521 DOI: 10.1080/09593330.2023.2179422] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Accepted: 02/02/2023] [Indexed: 06/18/2023]
Abstract
Microbial fuel cell technology draws attention with its ability to directly recover electrical energy from various organic materials. In this study, the operating conditions affecting the oxidation-reduction and electricity generation efficiency of MFC were optimized using the Taguchi Experimental Design model. Optimization was carried out for maximum power density, coulombic efficiency, azo dye removal, and COD removal. With the determined optimum conditions (cathode pH of 3.0, cathode oxygen status of anaerobic, anode substrate of pre-treated, external resistance of 100 Ω, cathode electrode type of plain carbon, cathode electrode surface of 22 cm2, cathode conductivity of 20 µs/cm), 177.03 mW/m2 power density, 7.50% coulombic efficiency, 91.26% azo dye removal efficiency and 21.61% COD removal efficiency were obtained. By Pareto analysis, it was determined that the power density, coulombic efficiency and COD removal efficiency were most affected by the substrate type at the anode, and the azo dye removal was most affected by the catholyte pH. The maximum power density and internal resistance of the MFC operated under optimum conditions were determined as 145.11 mW/m2 and 243.30 Ω, respectively by the polarization curve. Cyclic voltammetry was also performed for the electrochemical characterization of MFC operated under optimum conditions. An anodic peak at -183.2 mV and a cathodic peak at -181.2 mV was visible in the CV curve.
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Affiliation(s)
- Elif Durna Pişkin
- Department of Environmental Engineering, Faculty of Engineering, Kocaeli University, Kocaeli, Turkey
| | - Nevim Genç
- Department of Environmental Engineering, Faculty of Engineering, Kocaeli University, Kocaeli, Turkey
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Mohit A, Remya N. Exploring effects of carbon, nitrogen, and phosphorus on greywater treatment by polyculture microalgae using response surface methodology and machine learning. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 356:120728. [PMID: 38531138 DOI: 10.1016/j.jenvman.2024.120728] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Revised: 02/20/2024] [Accepted: 03/19/2024] [Indexed: 03/28/2024]
Abstract
The microalgae-based wastewater treatment is a promising technique that contribute to achieving sustainable development goals (SDGs), such as SDG-6, "Clean Water and Sanitation". However, it is strongly influenced by the initial composition of wastewater. In this study, the impact of initial organics and nutrient concentration on the removal of total organic carbon (TOC), total carbon (TC), ammonium (NH4+), total nitrogen (TN), and phosphate (PO43-) from greywater using native polyculture microalgae was explored. Response surface methodology was employed along with two machine learning approaches, AdaBoost and XGBoost, to evaluate the interactions among three main factors: TOC, NH4+, and PO43-, and their effects on treatment efficiency. The C/N ratios for achieving maximum TOC and TC removal efficiency of 99.2% and 97.7% were determined to be 10.3, and 65.4-73.6, respectively. Notably, the N/P ratio did not significantly affect their removal. The highest NH4+ removal efficiency, reaching 96.2%, was attained at C/N ratios of 4.3, 24.0, 38.2, and 212.9, coupled with N/P ratios of 0.3, 2.6, and 23.4. Highest TN removal efficiency of 77.2% was achieved at C/N and N/P ratios of 12.2 and 2.0, respectively. Highest PO43- removal of 78.8% was obtained at N/P ratio 12.8. However, C/N ratio did not affect the removal efficiency. Maintaining these specified C/N and N/P ratios in the influent greywater would ensure that the treated greywater meets the required standards for various reuse applications, including flushing, groundwater recharge, and surface water discharge. The integration of RSM with AdaBoost and XGBoost provided accurate predictions of removal efficiencies. For all the models, XGBoost had the highest R2, and lowest MAE and MSE values. The cross validation of RSM models with AdaBoost and XGBoost further reinforced the reliability of these models in predicting treatment outcomes.
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Affiliation(s)
- Aggarwal Mohit
- School of Infrastructure, Indian Institute of Technology Bhubaneswar, Odisha, 752050, India
| | - Neelancherry Remya
- School of Infrastructure, Indian Institute of Technology Bhubaneswar, Odisha, 752050, India.
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4
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Y. Saapi SS, Andrianisa HA, Zorom M, Mounirou LA, Kouassi HAA, Ahossouhe MS. New developments on vermifiltration as a bio-ecological wastewater treatment technology: Mechanism, application, performance, modelling, optimization, and sustainability. Heliyon 2024; 10:e25795. [PMID: 38375316 PMCID: PMC10875448 DOI: 10.1016/j.heliyon.2024.e25795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 01/22/2024] [Accepted: 02/02/2024] [Indexed: 02/21/2024] Open
Abstract
The review discusses the advancements in vermifiltration research over the last decade, focusing on pollution removal mechanisms, system performance, the fate of filter components, and by-products. Vermifiltration has demonstrated remarkable capabilities, particularly in treating highly contaminated wastewater with Chemical Oxygen Demand (COD) levels exceeding 92,000 mg/L and Biochemical Oxygen Demand (BOD5) levels over 25,000 mg/L, achieving removal rates of approximately 89% and 91%, respectively. Importantly, vermifiltration maintains its effectiveness even with fluctuating organic loads at the inlet, thanks to optimization of parameters like Hydraulic Loading Rate, biodegradable organic strength, earthworm density and active layer depth. Clogging issues can be minimized through parameters optimization. The review also highlights vermifiltrations' potential in co-treating the organic fraction of municipal solid waste while significantly reducing heavy metal concentrations, including Cd, Ni, Pb, Cu, Cr, and Zn, during the treatment process. Earthworms play a pivotal role in the removal of various components, with impressive removal percentages, such as 75% for Total Organic Carbon (TOC), 86% for Total COD, 87% for BOD5, 59% for ammonia nitrogen, and 99.9% for coliforms. Furthermore, vermifiltration-treated effluents can be readily utilized in agriculture, with the added benefit of producing vermicompost, a nutrient-rich biofertilizer. The technology contributes to environmental sustainability, as it helps reduce greenhouse gas emissions (GHG), thanks to earthworm activity creating an aerobic environment, minimizing GHG production compared to other wastewater treatment methods. In terms of pollutant degradation modeling, the Stover-Kincannon model outperforms the first-order and Grau second-order models, with higher regression coefficients (R2 = 0.9961 for COD and R2 = 0.9353 for TN). Overall, vermifiltration emerges as an effective and sustainable wastewater treatment solution, capable of handling challenging wastewater sources, while also producing valuable by-products and minimizing environmental impacts.
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Affiliation(s)
- Sidesse S. Y. Saapi
- Laboratoire Eaux, Hydro-Systèmes et Agriculture (LEHSA), Institut International d’Ingénierie de l’Eau et de l’Environnement (2iE), Rue de la Science, P.O. Box 594, Ouagadougou, 01, Burkina Faso
| | - Harinaivo A. Andrianisa
- Laboratoire Eaux, Hydro-Systèmes et Agriculture (LEHSA), Institut International d’Ingénierie de l’Eau et de l’Environnement (2iE), Rue de la Science, P.O. Box 594, Ouagadougou, 01, Burkina Faso
| | - Malicki Zorom
- Laboratoire Eaux, Hydro-Systèmes et Agriculture (LEHSA), Institut International d’Ingénierie de l’Eau et de l’Environnement (2iE), Rue de la Science, P.O. Box 594, Ouagadougou, 01, Burkina Faso
| | - Lawani A. Mounirou
- Laboratoire Eaux, Hydro-Systèmes et Agriculture (LEHSA), Institut International d’Ingénierie de l’Eau et de l’Environnement (2iE), Rue de la Science, P.O. Box 594, Ouagadougou, 01, Burkina Faso
| | - Hemez Ange Aurélien Kouassi
- Laboratoire Eaux, Hydro-Systèmes et Agriculture (LEHSA), Institut International d’Ingénierie de l’Eau et de l’Environnement (2iE), Rue de la Science, P.O. Box 594, Ouagadougou, 01, Burkina Faso
| | - Mahugnon Samuel Ahossouhe
- Laboratoire Eaux, Hydro-Systèmes et Agriculture (LEHSA), Institut International d’Ingénierie de l’Eau et de l’Environnement (2iE), Rue de la Science, P.O. Box 594, Ouagadougou, 01, Burkina Faso
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Dey Chowdhury S, Bhunia P, Surampalli RY, Zhang TC. Effects of bed depths and the ratio of aerobic to anaerobic zone on the performance of horizontal subsurface flow macrophyte-assisted high-rate vermifilters treating synthetic brewery wastewater. WATER ENVIRONMENT RESEARCH : A RESEARCH PUBLICATION OF THE WATER ENVIRONMENT FEDERATION 2024; 96:e10993. [PMID: 38348629 DOI: 10.1002/wer.10993] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 12/31/2023] [Accepted: 01/25/2024] [Indexed: 02/15/2024]
Abstract
Effects of total vermibed depth, as well as the ratio of aerobic (the unsubmerged) to anaerobic (the submerged) zone on the performance of the horizontal subsurface flow macrophyte-assisted vermifilters (HSSF-MAVFs) treating synthetic brewery wastewater at a higher hydraulic loading rate (HLR), were investigated for the first time. Results showed that the HSSF-MAVF with a 50 cm total and 18 cm submerged vermibed depth yielded the optimum removal of the pollutants, ensuring a (91.2 ± 1.7)%, (81.8 ± 1.9)%, (67.4 ± 3.9)%, and (63.1 ± 2.3)% removal of chemical oxygen demand (COD), ammonium N (NH4 + -N), total N (TN), and organic N, respectively, whereas there was an increase of (142 ± 6.3)% in the effluent nitrate-N (NO3 - -N) than that in the influent. At the optimum condition, the effluent concentrations of all the pollutants including COD, NH4 + -N, NO3 - -N, TN, and organic N were well below the surface water discharge standards specified by the Central Pollution Control Board (CPCB), and thus, the effluent of the HSSF-MAVF could be safely discharged into the surface water bodies. PRACTITIONER POINTS: Total vermibed depth of HSSF-MAVFs was optimized for organic and nitrogen removal. HSSF-MAVFs were subjected to the higher HLR of synthetic brewery wastewater. Removal of COD and NH4 + -N was decreased with the increase in submerged bed depth. Removal of organic N and TN was increased with the increase in submerged bed depth. Total/unsubmerged bed depth had a positive impact on the organic and N removal.
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Affiliation(s)
- Sanket Dey Chowdhury
- Environmental Engineering, School of Infrastructure, Indian Institute of Technology Bhubaneswar, Bhubaneswar, India
| | - Puspendu Bhunia
- Environmental Engineering, School of Infrastructure, Indian Institute of Technology Bhubaneswar, Bhubaneswar, India
| | - Rao Y Surampalli
- Global Institute for Energy, Environment, and Sustainability, Lenexa, Kansas, USA
| | - Tian C Zhang
- Civil & Environmental Engineering Department, College of Engineering, Scott Campus (Omaha), University of Nebraska-Lincoln, Lincoln, Nebraska, USA
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Drzymała J, Kalka J. Effects of diclofenac, sulfamethoxazole, and wastewater from constructed wetlands on Eisenia fetida: impacts on mortality, fertility, and oxidative stress. ECOTOXICOLOGY (LONDON, ENGLAND) 2023; 32:858-873. [PMID: 37633869 PMCID: PMC10533613 DOI: 10.1007/s10646-023-02690-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 08/08/2023] [Indexed: 08/28/2023]
Abstract
Soil contamination with micropollutants is an important global problem and the impact of these pollutants on living organisms cannot be underestimated. The effects of diclofenac (DCF) and sulfamethoxazole (SMX), their mixture (MIX), and wastewater containing these drugs on the mortality and reproduction of Eisenia fetida were investigated. The impact on the activities of antioxidant enzymes in earthworm cells was also assessed. Furthermore, the influence of the following parameters of the vertical flow constructed wetlands on wastewater toxicity was investigated: the dosing system, the presence of pharmaceuticals and the plants Miscanthus giganteus. The compounds and their mixture significantly affected the reproduction and mortality of earthworms. The calculated values of LC50,28 days values were 3.4 ± 0.3 mg kg-1 for DCF, 1.6 ± 0.3 mg kg-1 for SMX, and 0.9 ± 0.1 mg kg-1 for MIX. The EC50 (reproduction assay) for DCF was 1.2 ± 0.2 mg kg-1, whereas for SMX, it was 0.4 ± 0.1 mg kg-1, and for MIX, it was 0.3 ± 0.1 mg kg-1, respectively. The mixture toxicity index (MTI) was calculated to determine drug interactions. For both E. fetida mortality (MTI = 3.29) and reproduction (MTI = 3.41), the index was greater than 1, suggesting a synergistic effect of the mixture. We also observed a negative effect of wastewater (raw and treated) on mortality (32% for raw and 8% for treated wastewater) and fertility (66% and 39%, respectively) of E. fetida. It is extremely important to analyze the harmfulness of microcontaminants to organisms inhabiting natural environments, especially in the case of wastewater for irrigation of agricultural fields.
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Affiliation(s)
- Justyna Drzymała
- The Biotechnology Centre, Silesian University of Technology, Gliwice, Poland.
| | - Joanna Kalka
- Environmental Biotechnology Department, Faculty of Energy and Environmental Engineering, Silesian University of Technology, Gliwice, Poland
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Nsiah-Gyambibi R, Acheampong E, Von-Kiti E, Larbi Ayisi C. Performance evaluation of developed macrophyte-assisted vermifiltration system designed with varied macrophytes and earthworm species for domestic wastewater treatment. PLoS One 2023; 18:e0281953. [PMID: 36857364 PMCID: PMC9977024 DOI: 10.1371/journal.pone.0281953] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Accepted: 02/04/2023] [Indexed: 03/02/2023] Open
Abstract
Development of sustainable technology to treat domestic wastewater with added advantages of cost reduction and improved handling efficiency is crucial in developing countries. This is because, domestic wastewater from households are stored in septic tanks and are poorly treated prior discharge. This study developed a macrophyte-assisted vermifiltration (MAV) system to treat domestic wastewater. The MAV system is an integrated approach of macrophytes and earthworms in a vermifiltration and complex physicochemical mechanism processes. The use of different macrophyte and earthworm species was hypothesized by the study to affect and vary the treatment performance of the developed MAV. The study therefore aimed to evaluate the treatment performance of the developed MAV when three varied macrophyte species (Eichhornia crassopes, Pistia stratiotes and Spirodela sp.) and two varied earthworm species (Eisenia fetida and Eudrilus eugeniae) were used to design the treatment system. Treated effluents were collected every 48hours within two weeks for physico-chemical, pathogen and helminth analysis. The contaminants (Ntot, NH3, NO3-N and Ptot) in the wastewater were high (>50 mgL-1, >5 mgL-1, >1 mgL-1 and >20 mgL-1 respectively). Results revealed that the developed MAV systems were effective in the removal of solids (>60%), nutrients (>60%) and pathogens (>90%). In most cases, there were no significant differences between the selected varied macrophytes and earthworms in the treatment performances. Results therefore demonstrated that the selected macrophytes combined with the earthworm species were suitable when used in the development of the MAV system. Developing the MAV with the selected varied macrophyte and earthworm species did not only contribute to the treatment of the wastewater, but also improved the vermiculture. Eudrilus eugeniae however demonstrated higher biomass gain (5-10% more) compared to Eisenia fetida.
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Affiliation(s)
- Rapheal Nsiah-Gyambibi
- Department of Civil Engineering, Regional Water and Environmental Sanitation Centre, UPO, College of Engineering Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
- Institute of Industrial Research, Council for Scientific and Industrial Research, Accra, Ghana
- * E-mail: ,
| | - Emmanuel Acheampong
- Institute of Industrial Research, Council for Scientific and Industrial Research, Accra, Ghana
| | - Elizabeth Von-Kiti
- Institute of Industrial Research, Council for Scientific and Industrial Research, Accra, Ghana
| | - Christian Larbi Ayisi
- Department of Water Resource and Sustainable Development, School of Sustainable Development, PMB, University of Environment and Sustainable Development, Somanya, Ghana
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Das P, Paul K. A review on integrated vermifiltration as a sustainable treatment method for wastewater. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 328:116974. [PMID: 36516714 DOI: 10.1016/j.jenvman.2022.116974] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 12/03/2022] [Accepted: 12/03/2022] [Indexed: 06/17/2023]
Abstract
To overcome the scarcity of fresh water, concerned authorities worldwide are bound to think about remediation and reuse of domestic and industrial effluents. The present review study on integrated vermifiltrationwith hydroponic system explains mechanism followed in system and presently the reutilization and remediation of domestic and industrial effluents. It explains the result of integrated vermifiltration and recognizes factors such as clogging, hydraulic loading rate or rain on bed, salinity, and sunlight affect the efficiency of system. The study also focuses on limitations associated with vermifiltration and also suggestions have been made for enhancing the sustainability and performance of existing practices. After literature review, integrated vermifiltration with hydroponic system considered as a natural and eco-friendly method for treating polluted water. Active zone of vermifilter remove organics, nitrate from nitrogen, total and dissolved phosphorus from wastewater. The vermifiltration and integrated vermifiltration with macrophyte able remove chemical oxygen demand (COD) in the range (53.7%-64.4%) and (75.5%-82.8%) respectively. The integrated system reduces land consumption and wastewater can be reutilized in cultivation.
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Affiliation(s)
- Pragyan Das
- Department of Civil Engineering, National Institute of Technology, Rourkela, 769008, India.
| | - KakoliKarar Paul
- Department of Civil Engineering, National Institute of Technology, Rourkela, 769008, India.
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Namaldi O, Azgin ST. Evaluation of the treatment performance and reuse potential in agriculture of organized industrial zone (OIZ) wastewater through an innovative vermifiltration approach. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 327:116865. [PMID: 36450165 DOI: 10.1016/j.jenvman.2022.116865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 11/01/2022] [Accepted: 11/22/2022] [Indexed: 06/17/2023]
Abstract
Vermifiltration (VF) is a natural and sustainable biofilter that has many advantages, including being energy-free, cost-effective, and allowing ease of application and maintenance. In this study, the effectiveness of a lab-scale VF system was assessed by the removal efficiency of total suspended solids, electrical conductivity, chemical oxygen demand, total nitrogen, total phosphorus, fecal coliform, and heavy metals in organized industrial zones (OIZ) and domestic wastewater (DW) for the first time. Additionally, the reuse suitability of the treated wastewater was determined by comparing different countries' and global irrigational criteria. The lab systems were built with four layers: one worm-bed and three varying filtering materials, and operated at an optimum hydraulic loading rate of 1.8-2 m3/m2/day for 45 days with Eisenia fetida as the earthworm species. The results demonstrated that removal efficiencies of total suspended solids and chemical oxygen demand were found to be 95% and 80% in OIZ wastewater and 90% and 88% in DW, respectively. Total nitrogen and total phosphorus were removed at rates of 69% and 67% in OIZ wastewater, respectively, and 84% and 74% in DW. Besides, the VF system has shown satisfactory removal performance for heavy metals ranging from 51% to 77% in OIZ wastewater that has met Turkish national wastewater discharge limits. Although the final characterization of treated wastewater was suitable, heavy metal and fecal coliform levels have not met many countries' irrigation water quality criteria. To meet global irrigation standards and to enhance the VF performance, further experimental studies should be carried out, including parameters such as bed material type in the reactor, worm type, and different operating conditions.
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Affiliation(s)
- Onur Namaldi
- Department of Environment Engineering, Erciyes University, 38039, Kayseri, Turkey.
| | - Sukru Taner Azgin
- Department of Environment Engineering, Erciyes University, 38039, Kayseri, Turkey; Energy Conversions Research and Application Center, Erciyes University, 38039, Kayseri, Turkey.
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Jiang L, Yao J, Ren G, Sheng N, Guo Y, Dai J, Pan Y. Comprehensive profiles of per- and polyfluoroalkyl substances in Chinese and African municipal wastewater treatment plants: New implications for removal efficiency. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 857:159638. [PMID: 36280053 DOI: 10.1016/j.scitotenv.2022.159638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Revised: 10/09/2022] [Accepted: 10/18/2022] [Indexed: 06/16/2023]
Abstract
Municipal wastewater treatment plants (WWTPs) can reflect the pollution status of per- and polyfluoroalkyl substances (PFASs) pollution. Here, matched influent, effluent, and sludge samples were collected from 58 municipal WWTPs in China, South Sudan, Tanzania, and Kenya. Target and suspect screening of PFASs was performed to explore their profiles in WWTPs and assess removal efficiency and environmental emissions. In total, 155 and 58 PFASs were identified in WWTPs in China and Africa, respectively; 146 and 126 PFASs were identified in wastewater and sludge, respectively. Novel compounds belonging to per- and polyfluoroalkyl ether carboxylic acids (PFECAs) and sulfonic acids (PFESAs), hydrogen-substituted polyfluorocarboxylic acids (H-PFCAs), and perfluoroalkyl sulfonamides (PFSMs) accounted for a considerable proportion of total PFASs (ΣPFASs) in Chinese WWTPs and were also widely detected in African samples. In China, estimated national emissions of ΣPFASs in WWTPs exceeded 16.8 t in 2015, with >60 % originating from emerging PFASs. Notably, current treatment processes are not effective at removing PFASs, with 35 of the 54 WWTPs showing emissions higher than mass loads. PFAS removal was also structure dependent. Based on machine learning models, we found that molecular descriptors (e.g., LogP and molecular weight) may affect adsorption behavior by increasing hydrophobicity, while other factors (e.g., polar surface area and molar refractivity) may play critical roles in PFAS removal and provide novel insights into PFAS pollution control. In conclusion, this study comprehensively screened PFASs in municipal WWTPs and determined the drivers affecting PFAS behavior in WWTPs based on machine learning models.
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Affiliation(s)
- Lulin Jiang
- State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Jingzhi Yao
- State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Ge Ren
- National Institute of Metrology, Beijing 100029, China
| | - Nan Sheng
- State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Yong Guo
- Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, China
| | - Jiayin Dai
- State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Yitao Pan
- State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.
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11
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Dey Chowdhury S, Bhunia P, Surampalli RY. Vermifiltration: Strategies and techniques to enhance the organic and nutrient removal performance from wastewater. WATER ENVIRONMENT RESEARCH : A RESEARCH PUBLICATION OF THE WATER ENVIRONMENT FEDERATION 2022; 94:e10826. [PMID: 36518049 DOI: 10.1002/wer.10826] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 11/21/2022] [Accepted: 11/25/2022] [Indexed: 06/17/2023]
Abstract
The vermifiltration (VF) technology has gained significant attention as a green alternative for remediating domestic and industrial wastewater over the last few decades. Of late, the implementation of various modifications to the orthodox VF technology, including tweaks in the design and operation of the vermifilters, has been portrayed in the available literature. However, owing to the scatteredness of the available information, the knowledge regarding the execution of the modified vermifilters is still inadequate. Hence, an effort has been made to comprehensively overview the innovative strategies and techniques adopted to improve the organic and nutrient removal potential of the VFs from wastewater. In addition, future perspectives have been recognized to design more efficient and sustainable VFs. This review explores more of such novel tactics to improve the performance of the VF technology regarding organic and nutrient removal from wastewater. PRACTITIONER POINTS: Innovative strategies and techniques implemented to VF technology were comprehensively overviewed. Design modification and advantages of each innovation were highlighted. The pollutant removal performance of every modification was emphasized. Modified vermifilters were better than the conventional vermifilters in terms of organic and nutrient removal from the wastewater.
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Affiliation(s)
- Sanket Dey Chowdhury
- Environmental Engineering, School of Infrastructure, Indian Institute of Technology Bhubaneswar, Bhubaneswar, India
| | - Puspendu Bhunia
- Environmental Engineering, School of Infrastructure, Indian Institute of Technology Bhubaneswar, Bhubaneswar, India
| | - Rao Y Surampalli
- Global Institute for Energy, Environment, and Sustainability, Lenexa, Kansas, USA
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12
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Zhao X, Liu X, Xing Y, Wang L, Wang Y. Evaluation of water quality using a Takagi-Sugeno fuzzy neural network and determination of heavy metal pollution index in a typical site upstream of the Yellow River. ENVIRONMENTAL RESEARCH 2022; 211:113058. [PMID: 35255414 DOI: 10.1016/j.envres.2022.113058] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Revised: 02/25/2022] [Accepted: 02/27/2022] [Indexed: 06/14/2023]
Abstract
Assessment of river water quality is very important for understanding the impact of human activities on aquatic ecosystems. As the second-largest river in China, the Yellow River's water environment is closely related to the social development and water security of northern China. The Huangshui River is a major tributary of the upper Yellow River, and it supplies water to cities in the lower reaches. In this study, a Takagi-Sugeno (T-S) fuzzy neural network was used to evaluate water quality of the Huangshui River, and pollutant sources were analyzed. The heavy metal pollution index (HPI) was calculated to assess the heavy metal pollution level, and the health risks posed by heavy metal elements were assessed. The results indicated that the main contaminants in the Huangshui River were ammonia nitrogen (NH3-N) and total phosphorus (TP), which was affected by various activities of industry, agriculture, and urbanization, and the maximum concentration of NH3-N and TP was 5.90 mg/L and 0.36 mg/L, respectively. The T-S evaluation results of some points in the middle reaches were 3.317 and 3.197, which belonged to Level Ⅳ and the water quality was poor. The concentrations of Cu, Zn and Cr in the river were 0.57-44.58 μg/L, 10-122.50 μg/L and 2-28.67 μg/L, respectively, and they were relatively large. The T-S fuzzy neural network could evaluate water quality, avoiding extreme evaluation results by using fuzzy rules to reduce the influence of pollutant concentrations that are too high or too low. In addition to qualitative categorization of water quality, this approach can also quantitatively assess water quality within a single category. The results of water quality assessment could provide a scientific data support for river management.
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Affiliation(s)
- Xiaohong Zhao
- School of Civil Engineering, Chang'an University, Xi'an, 710061, China
| | - Xiaojie Liu
- Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China
| | - Yue Xing
- School of Civil Engineering, Chang'an University, Xi'an, 710061, China
| | - Lingqing Wang
- Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China.
| | - Yong Wang
- Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China
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13
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Miito GJ, Ndegwa PM, Alege FP, Coulibaly SS, Harrison J. Efficacy of a vermifilter at mitigating greenhouse gases and ammonia emissions from dairy wastewater. JOURNAL OF ENVIRONMENTAL QUALITY 2022; 51:644-655. [PMID: 35507691 DOI: 10.1002/jeq2.20367] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Accepted: 04/19/2022] [Indexed: 06/14/2023]
Abstract
Dairy effluent is a potential source of gaseous pollutants associated with global warming and soil acidification. Mitigating such emissions during handling and storage requires substantial financial and labor input. This study evaluated a low-cost technology for mitigating gaseous emissions from dairy wastewater. For 9 mo, a pilot-scale vermifilter system installed on a commercial dairy farm was studied. Bimonthly samples of the dairy wastewater influent and effluent from the vermifilter system were collected. These samples' potential gas emissions (ammonia [NH3 ], methane [CH4 ], carbon dioxide [CO2 ], and nitrous oxide [N2 O]) were measured using a closed-loop dynamic flux chamber method. Results indicated the following reductions in emissions of these gases by the vermifilter system: 84-100% for NH3 , 58-82% for CO2 , and 95-100% for CH4 . Nitrous oxide emissions were mainly below our instrument detection limits and were thus not reported. The vermifilter showed the potential of reducing the global warming potential from the dairy wastewater by up to 100%. This study further indicated that higher ambient temperatures led to higher emissions of CH4 (R2 = .56) and NH3 (R2 = .53) from untreated dairy wastewater. Overall, the vermifilter system has potential to mitigate gaseous emissions from dairy wastewater.
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Affiliation(s)
- Gilbert J Miito
- Dep. of Biological Systems Engineering, Washington State Univ., Pullman, WA, 99164, USA
| | - Pius M Ndegwa
- Dep. of Biological Systems Engineering, Washington State Univ., Pullman, WA, 99164, USA
| | | | - Sifolo S Coulibaly
- Dep. of Biological Sciences, Univ. Peleforo Gon Coulibaly, Korhogo, BP, 1328, Côte d'Ivoire
| | - Joe Harrison
- Dep. of Animal Sciences, Washington State Univ., Pullman, WA, 99164, USA
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14
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Tahar A, Feighan J, Hannon L, Clifford E. Optimization of operational conditions and performances of pilot scale lumbrifiltration for real raw municipal wastewater treatment. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:32717-32731. [PMID: 35015226 DOI: 10.1007/s11356-021-18259-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Accepted: 12/17/2021] [Indexed: 06/14/2023]
Abstract
Lumbrifiltration (LF) has been promoted as a low-cost, low maintenance and efficient solution for domestic and municipal wastewater treatment especially. However, there have been limited studies investigating the optimal operating conditions and long-term performances of LF systems (especially in temperate climates). The key objectives of this study were to (i) to present an outcome of the operating conditions and associated performance of LF the systems studied in the literature regarding removal efficiencies for nutrients and organic matter (OM) in municipal and domestic wastewater (WW) treatment contexts, (ii) to generate long term and reliable results on the potential performances of LF systems for the treatment of real municipal WW (for both OM and nutrients), (iii) to optimize operational conditions such as active layer height, earthworms density, HLR and earthworms type, conditions for which it is still unclear from the current literature which are optimal, and (iv) to assess the performances of the LF in a "temperate climate" context. Overall, LF systems showed high removal efficiencies for organic matter and nutrients for all the operating conditions tested. The study also confirmed the positive impact of earthworms in achieving high level of nitrification of ammonium after a short start-up period. The system operation and performances were maintained without maintenance for the whole duration of the study (over 250 days), showing the potential for keeping high level of performances for long-term periods. Recommendations are given in relation to LF system design such as optimal active layer height and hydraulic loading rate. The study also demonstrated the applicability and potential of Dendrobaena veneta as an alternative to Eisenia fetida (the latter generally being used in previous studies but are less available in some areas of Europe) for application in municipal wastewater treatment by LF.
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Affiliation(s)
- Alexandre Tahar
- Department of Civil Engineering, School of Engineering, NUI Galway, Alice Perry Engineering Building, National University of Ireland, Galway, Ireland.
| | - James Feighan
- Department of Civil Engineering, School of Engineering, NUI Galway, Alice Perry Engineering Building, National University of Ireland, Galway, Ireland
| | - Louise Hannon
- Department of Civil Engineering, School of Engineering, NUI Galway, Alice Perry Engineering Building, National University of Ireland, Galway, Ireland
| | - Eoghan Clifford
- Department of Civil Engineering, School of Engineering, NUI Galway, Alice Perry Engineering Building, National University of Ireland, Galway, Ireland
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15
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Genç N, Durna E, Kacıra E. The preference of the most appropriate radical-based regeneration process for spent activated carbon by the PROMETHEE approach. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:5240-5255. [PMID: 34417697 DOI: 10.1007/s11356-021-15833-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Accepted: 08/02/2021] [Indexed: 06/13/2023]
Abstract
In this study, regeneration of spent granular activated carbon (GAC) with reactive dye by hydroxyl and sulfate radical-based advanced oxidation processes (microwave (MW) +persulfate (PS)), (Fe(II)+ PS), and (O3 + H2O2) were evaluated. The adsorption of the dye to the GAC surface was characterized by chemisorption and Langmuir isotherm. Regeneration processes have been optimized by the response surface methodology to determine the operating conditions that will provide the highest adsorptive capacity. The optimum conditions of (MW + PS), (Fe (II) + PS), and (O3 + H2O2) processes were process PS anion of 45.52 g/L, pH of 11.4, MW power of 126 W, and duration of 14.56 min; Fe (II) of 3.58 g/L, PS anion of 73.5 g/L, duration of 59.8 min, and pH of 10.9; and H2O2 of 2.8 mole/L, flow rate of 8.14 mg ozone/L, duration of 32.8 min, and pH of 5.3, respectively. For (MW + PS), (Fe (II) + PS), and (O3 + H2O2) processes, the adsorptive capacity under optimum conditions was found as 4.36, 8.89, and 8.12 mg dye/g GAC, respectively. For (Fe (II) + PS) and (O3 + H2O2) processes, these values are approximately equal to the adsorptive capacity of raw GAC (8.01 mg dye/g GAC). The predicted values of the adsorption capacities by the obtained models were in good agreement with the actual experimental results. Preference Ranking Organization Method for Enrichment Evaluation approach was used in the preference of the appropriate regeneration process. The adsorptive capacity of regenerated GAC, operating cost of the regeneration process, change in the adsorptive capacity during the regeneration cycle, and carbon mass loss criteria were taken into account. The order of preference of regeneration processes was determined as (Fe (II) + PS)> (MW + PS)> (O3 + H2O2) considering all criteria.
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Affiliation(s)
- Nevim Genç
- Department of Environmental Engineering, Faculty of Engineering, Kocaeli University, 41380, Kocaeli, Turkey.
| | - Elif Durna
- Department of Environmental Engineering, Faculty of Engineering, Kocaeli University, 41380, Kocaeli, Turkey
| | - Esin Kacıra
- Department of Environmental Engineering, Faculty of Engineering, Kocaeli University, 41380, Kocaeli, Turkey
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16
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Yuvaraj A, Thangaraj R, Karmegam N, Ravindran B, Chang SW, Awasthi MK, Kannan S. Activation of biochar through exoenzymes prompted by earthworms for vermibiochar production: A viable resource recovery option for heavy metal contaminated soils and water. CHEMOSPHERE 2021; 278:130458. [PMID: 34126688 DOI: 10.1016/j.chemosphere.2021.130458] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 03/26/2021] [Accepted: 03/28/2021] [Indexed: 06/12/2023]
Abstract
The industrial revolution and indiscriminate usage of a wide spectrum of agrochemicals account for the dumping of heavy metals in the environment. In-situ/ex-situ physical, chemical, and bioremediation strategies with pros and cons have been adopted for recovering metal contaminated soils and water. Therefore, there is an urgent requirement for a cost-effective and environment-friendly technique to combat metal pollution. Biochar combined with earthworms and vermifiltration is a suitable emerging technique for the remediation of metal-polluted soils and water. The chemical substances (e.g., sodium hydroxide, zinc chloride, potassium hydroxide, and phosphoric acid) have been used to activate biochar, which also faces several shortcomings. Studies reveal that extracellular enzymes have been used to activate biochar which is produced by earthworms and microbes that can alter the surface of the biochar. The present review focuses on the global scenario of metal pollution and its remediation through biochar activation using earthworms. The earthworms and biochar can produce "vermibiochar" which is capable of reducing the metal ions from contaminated water and soils. The vermifiltration can be a suitable technology for metal removal from wastewater/effluent. Thus, the biochar has a trick of producing entirely new options at a time when vermifiltration and other technologies are least expected. Further attention to the biochar-assisted vermifiltration of different sources of wastewater is required to be explored for the large-scale utilization of the process.
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Affiliation(s)
- Ananthanarayanan Yuvaraj
- Vermitechnology and Ecotoxicology Laboratory, Department of Zoology, School of Life Sciences, Periyar University, Salem, 636 011, Tamil Nadu, India
| | - Ramasundaram Thangaraj
- Vermitechnology and Ecotoxicology Laboratory, Department of Zoology, School of Life Sciences, Periyar University, Salem, 636 011, Tamil Nadu, India.
| | - Natchimuthu Karmegam
- Department of Botany, Government Arts College (Autonomous), Salem, 636 007, Tamil Nadu, India
| | - Balasubramani Ravindran
- Department of Environmental Energy and Engineering, Kyonggi University, Youngtong - Gu, Suwon, 16227, South Korea; Center for Environmental Nuclear Research, Directorate of Research, SRM Institute of Science and Technology, SRM Nagar, Kattankulathur, 603203, Kanchipuram, Chennai, Tamil Nadu, India.
| | - Soon Woong Chang
- Department of Environmental Energy and Engineering, Kyonggi University, Youngtong - Gu, Suwon, 16227, South Korea
| | - Mukesh Kumar Awasthi
- College of Natural Resources and Environment, Northwest A&F University, Taicheng Road 3#, Yangling, Shaanxi, 712100, China.
| | - Soundarapandian Kannan
- Cancer Nanomedicine Laboratory, Department of Zoology, School of Life Sciences, Periyar University, Salem, 636 011, Tamil Nadu, India
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17
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Chen J, Liu Y, Liu K, Hu L, Yang J, Wang X, Song ZL, Yang Y, Tang M, Wang R. Bacterial community composition of internal circulation reactor at different heights for large-scale brewery wastewater treatment. BIORESOURCE TECHNOLOGY 2021; 331:125027. [PMID: 33798858 DOI: 10.1016/j.biortech.2021.125027] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2021] [Revised: 03/13/2021] [Accepted: 03/16/2021] [Indexed: 06/12/2023]
Abstract
This study analyzed bacterial community structure for large-scale brewery wastewater treatment at different heights in internal circulation (IC) reactor. Proteobacteria, Bacteroidetes and Chloroflexi were dominant bacteria, which accounted for 64.17%, 64.04%, 59.87% and 55.79% in phylum level, respectively. The unidentified bacteria were accounted for a large proportion in genus level, available data showed that Longilinea, Desulfomicrobium, Caldithrix, Geobacter and Syntrophorhabdus were relatively abundant. Organic fermentation, hydrolysis, and acidification were mainly completed at the bottom, and production of hydrogen and methane were completed in the upper and middle part of reactor. Alpha diversity and cluster distance analysis showed the bacterial community could be divided into bottom, middle and upper part of IC reactor. The IC reactor possessed the CODCr removal efficiency of 80% - 84.09%, and BOD5 of 77.50% - 86% for brewery wastewater. This study would provide bacterial analysis references of IC reactor for industrial wastewater treatment in future.
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Affiliation(s)
- Junfeng Chen
- Department of Environmental Science, School of Life Science, Qufu Normal University, Qufu 273165, PR China
| | - Yanyan Liu
- Department of Environmental Science, School of Life Science, Qufu Normal University, Qufu 273165, PR China.
| | - Kai Liu
- Department of Environmental Science, School of Life Science, Qufu Normal University, Qufu 273165, PR China
| | - Lijun Hu
- Department of Environmental Science, School of Life Science, Qufu Normal University, Qufu 273165, PR China
| | - Jiaqi Yang
- Department of Environmental Science, School of Life Science, Qufu Normal University, Qufu 273165, PR China
| | - Xuemei Wang
- Department of Environmental Science, School of Life Science, Qufu Normal University, Qufu 273165, PR China
| | - Zhi-Ling Song
- Key Laboratory of Optic-electric Sensing and Analytical Chemistry for Life Science, MOE, Shandong Key Laboratory of Biochemical Analysis, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, PR China
| | - Yuewei Yang
- Department of Environmental Science, School of Life Science, Qufu Normal University, Qufu 273165, PR China
| | - Meizhen Tang
- Department of Environmental Science, School of Life Science, Qufu Normal University, Qufu 273165, PR China
| | - Renjun Wang
- Department of Environmental Science, School of Life Science, Qufu Normal University, Qufu 273165, PR China
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18
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Dey Chowdhury S, Bhunia P. Simultaneous Carbon and Nitrogen Removal from Domestic Wastewater using High Rate Vermifilter. Indian J Microbiol 2021; 61:218-228. [PMID: 33927463 PMCID: PMC8039078 DOI: 10.1007/s12088-021-00936-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Accepted: 03/29/2021] [Indexed: 10/21/2022] Open
Abstract
Being a cost-effective and environmentally benign technology, vermifiltration has significantly replaced the available conventional wastewater remediation methods in many cases over the last few decades. The present work emphasizes on the investigation of the nitrogen transformation dynamics, in addition to the organic carbon abatement in the designed high rate hybrid vermifilter. Moreover, the economical sustainability of the vermifiltration technology has also been enlightened by creating a bridge with the concept of circular bio-economy. The designed high rate macrophyte-assisted vermifilter (MAVF) ascertained significant high nitrogen and organic carbon removal efficiencies from the real domestic sewage, considering the chemical oxygen demand (COD) of the influent and hydraulic loading rate (HLR) as the input variables. The designed MAVF facilitated the maximum ammonium nitrogen (NH4 +-N), organic nitrogen, and total kjeldahl nitrogen removal efficiencies up to 98.2 ± 0.70%, 100%, and 99 ± 0.47%, respectively when COD of the influent and HLR were 200 ± 25 mg/L and 3 ± 0.1 m3/m2-d, respectively. On the other hand, substantial enhancement in the nitrate nitrogen (NO3 --N) in the effluent (73 ± 10.55 times its influent concentration) was observed with influent COD of 200 ± 25 mg/L and HLR of 7 ± 0.2 m3/m2-d. When the influent COD and HLR were maintained at 700 ± 45 mg/L and 3 ± 0.1 m3/m2-d, respectively, the highest total nitrogen removal of 87 ± 2.25% was obtained. Alternatively, the influent COD of 200 ± 25 mg/L and HLR of 3 ± 0.1 m3/m2-d yielded the highest COD removal efficiency of 77 ± 1.59%. Hence, the outcome of the present research work strengthens the suitability of the vermifiltration technology as an economically and ecologically sound natural wastewater bio-remediation technology for the treatment of domestic wastewater.
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Affiliation(s)
- Sanket Dey Chowdhury
- Environmental Engineering, School of Infrastructure, Indian Institute of Technology Bhubaneswar, Bhubaneswar, Odisha 752 050 India
| | - Puspendu Bhunia
- Environmental Engineering, School of Infrastructure, Indian Institute of Technology Bhubaneswar, Bhubaneswar, Odisha 752 050 India
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19
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Priya AK, Pachaiappan R, Kumar PS, Jalil AA, Vo DVN, Rajendran S. The war using microbes: A sustainable approach for wastewater management. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 275:116598. [PMID: 33581625 DOI: 10.1016/j.envpol.2021.116598] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Revised: 01/16/2021] [Accepted: 01/24/2021] [Indexed: 06/12/2023]
Abstract
Anthropogenic activities and population growth have resulted in a reduced availability of drinking water. To ensure consistency in the existence of drinking water, it is inevitable to establish wastewater treatment plants (WWTPs). 70% of India's rural population was found to be without WWTP, waste disposal, and good sanitation. Wastewater has emerged from kitchens, washrooms, etc., with industry activities. This scenario caused severe damage to water resources, leading to degradation of water quality and pathogenic insects. Thus, it is a need of an hour to prompt for better WWTPs for both rural and urban areas. Many parts of the world have started to face severe water shortages in recent years, and wastewater reuse methods need to be updated. Clean water supply is not enough to satisfy the needs of the planet as a whole, and the majority of freshwater in the polar regions takes the form of ice and snow. The increasing population requires clean water for drinks, hygiene, irrigation, and various other applications. Lack of water and contamination of water result from human activities. 90% of wastewater is released to water systems without treatment in developing countries. Studies show that about 730 megatons of waste are annually discharged into water from sewages and other effluents. The sustenance of water resources, applying wastewater treatment technologies, and calling down the percentage of potable water has to be strictly guided by mankind. This review compares the treatment of domestic sewage to its working conditions, energy efficiency, etc. In this review, several treatment methods with different mechanisms involved in waste treatment, industrial effluents, recovery/recycling were discussed. The feasibility of bioaugmentation should eventually be tested through data from field implementation as an important technological challenge, and this analysis identifies many promising areas to be explored in the future.
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Affiliation(s)
- A K Priya
- Department of Civil Engineering, KPR Institute of Engineering and Technology, Coimbatore, 641027, India
| | - Rekha Pachaiappan
- Department of Sustainable Energy Management, Stella Maris College, Chennai, 600086, Tamilnadu, India
| | - P Senthil Kumar
- Department of Chemical Engineering, Sri Sivasubramaniya Nadar College of Engineering, Chennai, 603 110, India
| | - A A Jalil
- School of Chemical and Energy Engineering, Faculty of Engineering, Universiti Teknologi Malaysia, 81310, UTM, Johor Bahru, Johor, Malaysia; Centre of Hydrogen Energy, Institute of Future Energy, 81310, UTM, Johor Bahru, Johor, Malaysia
| | - Dai-Viet N Vo
- Center of Excellence for Green Energy and Environmental Nanomaterials (CE@GrEEN), Nguyen Tat Thanh University, 300A Nguyen Tat Thanh, District 4, Ho Chi Minh City, 755414, Viet Nam
| | - Saravanan Rajendran
- Departamento de Ingeniería Mecánica, Facultad de Ingeniería, Universidad de Tarapacá, Avda. General Velásquez, 1775, Arica, Chile.
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20
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Singh R, D'Alessio M, Meneses Y, Bartelt-Hunt S, Ray C. Nitrogen removal in vermifiltration: Mechanisms, influencing factors, and future research needs. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2021; 281:111868. [PMID: 33387734 DOI: 10.1016/j.jenvman.2020.111868] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 12/02/2020] [Accepted: 12/18/2020] [Indexed: 06/12/2023]
Abstract
To meet global health and sanitation goals, there is a continued need for sustainable wastewater treatment alternatives that require minimal energy and investment. Vermifiltration, a technology gaining relevance in Africa and Asia, may be an alternative to traditional wastewater treatment systems due to its cost-effectiveness, ease of application and maintenance, and sustainability. However, nitrogen removal in vermifiltration is not well understood since most of the prior research focuses on organics removal. Thus, a state of the art review is necessary to separately focus on the mechanisms associated with nitrogen removal in vermifiltration, along with the factors affecting nitrogen removal. For the first time, this review attempts to present the types of vermifilter based on their flow pattern. The review further discusses the current status of the application of vermifiltration, along with the benefits and limitations associated with the adoption of this technology. It also explores possible strategies that could be adopted to maximize the nitrogen removal potential of vermifilters as optimizing nitrogen removal is critical for improving the performance of vermifiltration based treatment systems.
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Affiliation(s)
- Rajneesh Singh
- Nebraska Water Center, University of Nebraska-Lincoln, NE, USA
| | - Matteo D'Alessio
- Department of Civil Engineering, University of Mississippi, MS, USA
| | - Yulie Meneses
- Daugherty Water for Food Global Institute, University of Nebraska-Lincoln, NE, USA
| | - Shannon Bartelt-Hunt
- Daugherty Water for Food Global Institute, University of Nebraska-Lincoln, NE, USA; Dept. of Civil and Environmental Engineering, University of Nebraska-Lincoln, NE, USA
| | - Chittaranjan Ray
- Nebraska Water Center, University of Nebraska-Lincoln, NE, USA; Daugherty Water for Food Global Institute, University of Nebraska-Lincoln, NE, USA; Dept. of Civil and Environmental Engineering, University of Nebraska-Lincoln, NE, USA.
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21
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Optimization of a Completely Mixed Anaerobic Biofilm Reactor (CMABR), Based on Brewery Wastewater Treatment. WATER 2021. [DOI: 10.3390/w13050606] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
In this study, brewery wastewater was used as the treatment in exploring the optimal conditions and maximum processing efficiency of the completely mixed anaerobic biofilm reactor (CMABR) under the conditions of hydraulic retention time (HRT) (18 h, 24 h, and 30 h) with a rotational speed (70 rpm, 100 rpm, and 130 rpm) and influent total alkalinity (TA) (20 mmol/L, 25 mmol/L, and 30 mmol/L), which was measured by the response surface methodology (RSM). The results indicated that the maximum chemical oxygen demand (COD) removal ratio was achieved under the following conditions: HRT of 21.42 h, rotational speed of 101.34 rpm, and influent TA of 25.22 mmol/L. Analysis by scanning electron microscope (SEM) showed that the microorganisms were successfully immobilized on the polyurethane fillers before the reactor began operation. High-throughput sequencing indicated that Methanothrix and Methanospirillum were the dominant contributors for COD removal in the CAMBR under these optimum conditions.
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22
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Srivastava A, K A, Nair A, Ram S, Agarwal S, Ali J, Singh R, Garg MC. Response surface methodology and artificial neural network modelling for the performance evaluation of pilot-scale hybrid nanofiltration (NF) & reverse osmosis (RO) membrane system for the treatment of brackish ground water. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2021; 278:111497. [PMID: 33130432 DOI: 10.1016/j.jenvman.2020.111497] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 09/20/2020] [Accepted: 10/07/2020] [Indexed: 06/11/2023]
Abstract
Artificial neural network (ANN) and response surface methodology (RSM) were employed to develop models for process optimisation of pilot scale nanofiltration (NF) and reverse osmosis (RO) membrane filtration system for the treatment of brackish groundwater. The process variables for this study were feed concentration, temperature, pH and pressure. The performance of NF/RO was assessed in terms of permeate flux, water recovery, salt rejection and specific energy consumption, which were considered as responses. The experimental design was employed to develop both RSM and ANN models. RSM model was validated for the whole range of experimental levels, while the ANN model was considered for the whole range of experimental design. RSM and ANN models were statistically analysed using analysis of variance (ANOVA). Further, the models were graphically compared for its predictive capacity. Numerical optimisation of NF and RO pilot plant to determine the optimum conditions were verified. Finally, using the optimum conditions, three hybrid configurations of NF and RO were studied to determine the best mode for the treatment of brackish groundwater. It was found that parallel NF-RO had a recovery of 57.18% and rejection of 44.89%, for RO-concentrate-NF (RO-C-NF) recovery was 49.55% and rejection of 38.64% & for NF-concentrate-RO (NF-C-RO), the recovery of 39.53% and rejection of 49.66% was obtained. Results obtained also suggested that the mode of configurations and the feed concentration affect the performance of the hybrid system.
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Affiliation(s)
- Alka Srivastava
- Amity Institute of Environmental Sciences, Amity University Uttar Pradesh, Sector 125, Noida, Uttar Pradesh, 201313, India.
| | - Aghilesh K
- Amity Institute of Environmental Sciences, Amity University Uttar Pradesh, Sector 125, Noida, Uttar Pradesh, 201313, India.
| | - Akhil Nair
- School of Engineering, Gautam Buddha University, Greater Noida, 201308, India.
| | - Shobha Ram
- School of Engineering, Gautam Buddha University, Greater Noida, 201308, India.
| | - Smriti Agarwal
- Department of Electronics and Communication Engineering, Motilal Nehru National Institute of Technology Allahabad, Prayagraj, Uttar Pradesh, 211004, India.
| | - Jahangeer Ali
- Biological System Engineering, University of Nebraska, Lincoln, United States.
| | - Rajneesh Singh
- Nebraska Water Center, University of Nebraska, Lincoln, United States.
| | - Manoj Chandra Garg
- Amity Institute of Environmental Sciences, Amity University Uttar Pradesh, Sector 125, Noida, Uttar Pradesh, 201313, India.
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23
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Chicaiza C, Huaraca L, Almeida-Naranjo CE, Guerrero VH, Villamar CA. Improvement of organic matter and nutrient removal from domestic wastewater by using intermittent hydraulic rates on earthworm-microorganism biofilters. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2020; 82:281-291. [PMID: 32941170 DOI: 10.2166/wst.2020.139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Biofilters based on earthworms-microorganisms represent, particularly in developing countries, an interesting alternative for domestic wastewater treatment due to their easy operation and low cost. However, there are several operational aspects that should be better understood in order to improve their performance. This paper studies the effect of using intermittent hydraulic loading rates to improve organic matter and nutrient removal from domestic wastewater using these biofilters. Three laboratory-scale columns, operating at a 2.5 m3 m-2day-1 hydraulic loading rate, were used. The B1-24 h, B2-8 h, B3-4 h column loading rates indicate that the columns were operated continuously for 24, 8 and 4 h, respectively. Each column (biomass biofilm/earthworms, redox potential, and head loss) and its corresponding operational performance parameters (TCOD, NH4 +, NO3 -, NO2 -, TP) were monitored. The results showed that the B2-8 h intermittent hydraulic loading rate results in the best global performance, with 74%, 57%, and 20% average removal efficiencies for TCOD, nitrogen, and phosphorus, respectively. Moreover, it showed the best biomass growth (biofilm and earthworms), activity (as redox potential changes) and the lowest clogging effects (up to -1.0 cm). The intermittent operation influences the behavior of the earthworm-microorganism biofilters and offers the possibility of optimizing its global performance and achieving a resilient technology.
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Affiliation(s)
- C Chicaiza
- Departamento de Ingeniería Civil y Ambiental, Escuela Politécnica Nacional, Ladrón de Guevara E11-253, 170525, Quito, Ecuador
| | - L Huaraca
- Departamento de Ingeniería Civil y Ambiental, Escuela Politécnica Nacional, Ladrón de Guevara E11-253, 170525, Quito, Ecuador
| | - C E Almeida-Naranjo
- Departamento de Ingeniería Mecánica, Facultad de Ingeniería Mecánica, Escuela Politécnica Nacional, Ladrón de Guevara E11-253, 170525, Quito, Ecuador
| | - V H Guerrero
- Departamento de Materiales, Escuela Politécnica Nacional, Ladrón de Guevara E11-253, 170525, Quito, Ecuador
| | - C A Villamar
- Departamento de Ingeniería en Obras Civiles, Facultad de Ingeniería, Universidad de Santiago de Chile, Av. Ecuador 3659, P.O. Box: 9170124, Estación Central, Santiago, Chile E-mail:
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24
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Niu Y, Liu X, Chang G, Guo Q. Treatment of isopropanol wastewater in an anaerobic fluidized bed microbial fuel cell filled with macroporous adsorptive resin as multifunctional biocarrier. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 719:137495. [PMID: 32120105 DOI: 10.1016/j.scitotenv.2020.137495] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Revised: 02/06/2020] [Accepted: 02/20/2020] [Indexed: 06/10/2023]
Abstract
The isopropanol (IPA) wastewater was treated in an anaerobic fluidized bed microbial fuel cell (AFB-MFC) filled with macroporous adsorptive resin (MAR) particles as multifunctional biocarrier. MAR was used as a biological carriers and adsorbent. MAR was characterized by scanning electron microscope. The diffusion of isopropanol in MAR was studied by Materials Studio (MS) software, and diffusion coefficients were analyzed and calculated by molecular dynamics simulation. The simulation results were qualitatively consistent with the available experimental data. The diffusivity of IPA in MAR increased firstly, with the increasing IPA weight, and then decreased. The maximum diffusivity was resulted to be 0.3722 Å2/ps. In addition, the response surface methodology (RSM) and Box-Behnken design were used to study the effects of initial IPA concentration, flow rate and external resistance on performance of power output and pollutant degradation. The optimal experimental condition was observed as initial IPA concentration of 483.49 mg/L, a flow rate of 57.70 mL/min, and external resistance of 5225.78 Ω. After 21 h of operation under the optimized conditions, the maximum power density was 135.73 ± 0.17 mW/m2 and the COD removal was 68.21 ± 0.24%, which increased by 65.85% and 9.29%, respectively.
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Affiliation(s)
- Yanjie Niu
- State Key Laboratory Base of Eco-Chemical Engineering in College of Chemical Engineering, Qingdao University of Science and Technology, Qingdao 266042, China
| | - Xinmin Liu
- State Key Laboratory Base of Eco-Chemical Engineering in College of Chemical Engineering, Qingdao University of Science and Technology, Qingdao 266042, China.
| | - Guozhang Chang
- State Key Laboratory of High-efficiency Coal Utilization and Green Chemical Engineering, College of Chemistry and Chemical Engineering, Ningxia University, Yinchuan 750021, China
| | - Qingjie Guo
- State Key Laboratory Base of Eco-Chemical Engineering in College of Chemical Engineering, Qingdao University of Science and Technology, Qingdao 266042, China; State Key Laboratory of High-efficiency Coal Utilization and Green Chemical Engineering, College of Chemistry and Chemical Engineering, Ningxia University, Yinchuan 750021, China
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25
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Singh R, Samal K, Dash RR, Bhunia P. Vermifiltration as a sustainable natural treatment technology for the treatment and reuse of wastewater: A review. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2019; 247:140-151. [PMID: 31247361 DOI: 10.1016/j.jenvman.2019.06.075] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 05/21/2019] [Accepted: 06/15/2019] [Indexed: 06/09/2023]
Abstract
With increasing urbanization and industrialization, the scarcity of freshwater is becoming rampant. To counteract this, authorities all over the world are forced to consider the treatment and reuse of the wastewater produced by either industries or domestic units. After an extensive literature survey, vermifiltration coupled with/without macrophyte has been identified as one of the best sustainable, natural and eco-friendly technology for the treatment and reuse of wastewater. Till date, it has been successfully applied for treating domestic wastewater. However, the results from very limited industrial applications are also encouraging and proving its worth for industrial wastewater remediation. The present review on vermifiltration deals with the mechanisms involved and its current status for the remediation and reutilisation of the effluents generated from domestic and industrial premises. The review successfully identifies and explicitly discusses the mechanisms involved in the vermifiltration. The review exhaustively discusses the performance of vermifiltration and identifies the factors contributing to the performance of vermifiltration, which could be of help in designing of the field scale vermifilter based treatment plant. The review identifies the limitations associated with the vermifiltration and suggests possible alternatives, aimed to improve its performance and applicability. The aim of this review is to bring the attention of prospective researchers to study each and every aspect related to the vermifiltration so that it may be adopted as a reliable and dependable technology for the remediation of several industrial effluents meeting the concept of "Zero discharge".
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Affiliation(s)
- Rajneesh Singh
- School of Infrastructure, Indian Institute of Technology Bhubaneswar, India
| | - Kundan Samal
- School of Infrastructure, Indian Institute of Technology Bhubaneswar, India
| | - Rajesh Roshan Dash
- School of Infrastructure, Indian Institute of Technology Bhubaneswar, India
| | - Puspendu Bhunia
- School of Infrastructure, Indian Institute of Technology Bhubaneswar, India.
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26
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Rezk H, Nassef AM, Inayat A, Sayed ET, Shahbaz M, Olabi AG. Improving the environmental impact of palm kernel shell through maximizing its production of hydrogen and syngas using advanced artificial intelligence. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 658:1150-1160. [PMID: 30677979 DOI: 10.1016/j.scitotenv.2018.12.284] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Revised: 12/17/2018] [Accepted: 12/18/2018] [Indexed: 06/09/2023]
Abstract
Fossil fuel depletion and the environmental concerns have been under discussion for energy production for many years and finding new and renewable energy sources became a must. Biomass is considered as a net zero CO2 energy source. Gasification of biomass for H2 and syngas production is an attractive process. The main target of this research is to improve the production of hydrogen and syngas from palm kernel shell (PKS) steam gasification through defining the optimal operating parameters' using a modern optimization algorithm. To predict the gaseous outputs, two PKS models were built using fuzzy logic based on the experimental data sets. A radial movement optimizer (RMO) was applied to determine the system's optimal operating parameters. During the optimization process, the decision variables were represented by four different operating parameters. These parameters include; temperature, particle size, CaO/biomass ratio and coal bottom ash (CBA) with their operating ranges of (650-750 °C), (0.5-1 mm), (0.5-2) and wt% (0.02-0.10), respectively. The individual and interactive effects of different combinations were investigated on the production of H2 and syngas yield. The optimized results were compared with experimental data and results obtained from Response Surface Methodology (RSM) reported in literature. The obtained optimal values of the operating parameters through RMO were found 722 °C, 0.92 mm, 1.72 and 0.06 wt% for the temperature, particle size, CaO/biomass ratio and coal bottom ash, respectively. The results showed that syngas production was significantly improved as it reached 65.44 vol% which was better than that obtained in earlier studies.
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Affiliation(s)
- Hegazy Rezk
- College of Engineering at Wadi Addawaser, Prince Sattam Bin Abdulaziz University, Saudi Arabia; Electrical Engineering Department, Faculty of Engineering, Minia University, Egypt.
| | - Ahmed M Nassef
- College of Engineering at Wadi Addawaser, Prince Sattam Bin Abdulaziz University, Saudi Arabia; Computers and Automatic Control Engineering Department, Faculty of Engineering, Tanta University, Egypt
| | - Abrar Inayat
- Department of Sustainable and Renewable Energy Engineering, University of Sharjah, Sharjah, United Arab Emirates
| | - Enas Taha Sayed
- Chemical Engineering Department, Faculty of Engineering, Minia University, Egypt; Center for Advanced Materials Research, University of Sharjah, PO Box 27272, Sharjah, United Arab Emirates
| | - Muhammad Shahbaz
- Department of Chemical Engineering, Universiti Teknologi PETRONAS, Bander Seri Iskander, Malaysia; Department of Chemical Engineering, University of Gujrat, Gujrat, Pakistan
| | - A G Olabi
- Department of Sustainable and Renewable Energy Engineering, University of Sharjah, Sharjah, United Arab Emirates; Mechanical Engineering and Design, Aston University, School of Engineering and Applied Science, Aston Triangle, Birmingham, B4 7ET, United Kingdom.
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27
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Singh R, Bhunia P, Dash RR. Optimization of bioclogging in vermifilters: A statistical approach. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2019; 233:576-585. [PMID: 30597351 DOI: 10.1016/j.jenvman.2018.12.065] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2018] [Revised: 12/12/2018] [Accepted: 12/19/2018] [Indexed: 06/09/2023]
Abstract
In the present research, an experiment was conducted with the objective of optimization of the role of earthworms in alleviating the bioclogging of a horizontal subsurface flow vermifilter (HSSFVF), caused due to the application of organics rich brewery wastewater. In this experiment, for the optimization of bioclogging of the vermifilters, the Box-Behnken Design (BBD) and response surface methodology (RSM) were involved. Hydraulic loading rate (HLR), influent COD and earthworm density (EWD) are the variables against which the bioclogging of the HSSFVF has been optimized. EWD of 9475 earthworms/m3, HLR of 1.84 m3/m2-d and influent COD of 3701 mg/L have been observed as the optimized values for the minimum bioclogging in the vermifiltration of brewery wastewater. At this optimum boundary conditions, the reduction in hydraulic conductivity was obtained as 1.49%, against the predicted value of 1.67% based upon the BBD model. The verification of the model against real brewery wastewater yielded insignificant error and thus very strongly portrays the suitability of the derived BBD model. The study indicates that the bioclogging from the vermifilters can be minimized, if the variables are optimized using the response surface methodology.
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Affiliation(s)
- Rajneesh Singh
- School of Infrastructure, Indian Institute of Technology, Bhubaneswar, India
| | - Puspendu Bhunia
- School of Infrastructure, Indian Institute of Technology, Bhubaneswar, India.
| | - Rajesh R Dash
- School of Infrastructure, Indian Institute of Technology, Bhubaneswar, India
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