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Gholipour A, Fragoso R, Galvão A, Duarte E. Water balance analysis in a novel pilot-scale of the Worm-sludge treatment reed bed (W-STRB) planted with Arundo donax. WATER RESEARCH 2024; 250:121066. [PMID: 38150856 DOI: 10.1016/j.watres.2023.121066] [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: 07/19/2023] [Revised: 11/06/2023] [Accepted: 12/23/2023] [Indexed: 12/29/2023]
Abstract
A one-year study of sludge treatment reed bed assisted with earthworms (W-STRB) was conducted in a temperate climate. The effects of using Eisenia fetid and Arundo donax on W-STRB water balance (WB) and dewatering efficiency (DE) were investigated. Four different bed configurations were tested: worm-planted (WP), planted (P), worm-control (W), and control (C), duplicated resulting in a total of eight units. The beds received a total of 24 cycles of mixed sewage sludge twice per month (average loading rate: 43.59 kg.DS. m-2.year-1). It was found seasonal variation played a significant role in WB and DE. During the dry season, the thickness of the residual sludge (RS) layer was less than 1 cm, with a dry solid (DS) content of over 80%, in contrast, the wet season indicated an increase in RS thickness to nearly 30 cm (DS < 15 % for all units). The WP unit exhibited the lowest RS accumulation, 22% less than the P, W, and C units. The subsurface layer had a 5% lower volatile solids (VS) content compared to the surface layers. After 132 days of a final resting, WP unit had the highest RS volume reduction of 65 % (DS = 71 % and VS = 53 %) and a RS thickness of 6 cm indicating a 10 % higher stabilization compared to P unit. The population of earthworms was 30% higher in the WP unit compared to the W unit. As the subsurface DS exceeded 20 % during the dry season, the population increased. The WP unit showed a 43% higher above-ground plant biomass compared to the P unit. In WB analysis, evapotranspiration (ET) was 46% higher in the WP unit (average daily ET = 5.44 mm in the dry season). The main process of water loss was through drainage and Awhile water content in RS layer was 57 % during feeding period. The water percolation rate of all units decreased by 99%, particularly during the wet season, reaching less than 0.1 m.day-1.
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Affiliation(s)
- Amir Gholipour
- LEAF - Linking Landscape, Environment, Agriculture and Food, Instituto Superior de Agronomia (ISA), University of Lisbon, Tapada da Ajuda, 1349-017, Lisbon, Portugal.
| | - Rita Fragoso
- LEAF - Linking Landscape, Environment, Agriculture and Food, Associated Laboratory TERRA, Instituto Superior de Agronomia (ISA), University of Lisbon, Tapada da Ajuda, 1349-017, Lisbon, Portugal
| | - Ana Galvão
- CERIS, Instituto Superior Técnico (IST), University of Lisbon, Av. Rovisco Pais, 1049-001, Lisbon, Portugal
| | - Elizabeth Duarte
- LEAF - Linking Landscape, Environment, Agriculture, and Food, Instituto Superior de Agronomia (ISA), University of Lisbon, Tapada da Ajuda, 1349-017, Lisbon, Portugal
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Singh S, Upadhyay S, Rani A, Sharma PK, Rawat JM, Rawat B, Prashant, Bhattacharya P. Assessment of pathogen removal efficiency of vertical flow constructed wetland treating septage. Sci Rep 2023; 13:18703. [PMID: 37907513 PMCID: PMC10618516 DOI: 10.1038/s41598-023-45257-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Accepted: 10/17/2023] [Indexed: 11/02/2023] Open
Abstract
Septage refers to the semi-liquid waste material that accumulates in septic tanks and other onsite sanitation systems. It is composed of a complex mixture of human excreta, wastewater, and various solid particles. Septage is a potential source of water pollution owing to presence of high organic content, significant pathogen concentrations, and a range of nutrients like nitrogen and phosphorus. The harmful impacts of septage pollution poses significant risks to public health through the contamination of drinking water sources, eutrophication of water bodies and spread of water borne diseases. Conventional septage treatment technologies often face limitations such as high operational costs, energy requirements, and the need for extensive infrastructure. Therefore, with an aim to treat septage through an alternative cost effective and energy-efficient technology, a laboratory-scale constructed wetland (CW) system (0.99 m2) consisting of a sludge drying bed and a vertical flow wetland bed was utilized for the treatment of septage. The sludge drying bed and vertical flow beds were connected in series and filled with a combination of gravel with varying sizes (ranging from 5 to 40 mm) and washed sand. Canna indica plants were cultivated on both beds to facilitate phytoremediation process. The system was operated with intermittent dosing of 30 Ltrs of septage every day for 2 months. The HRT of the system was fixed at 48 h. The average inlet loads of Biochemical Oxygen Demand (BOD5), Chemical Oxygen Demand (COD), and Total Suspended Solids (TSS) were measured as 150 ± 65.7 g m-2 day-1, 713 ± 443.9 g m-2 day-1, and 309 ± 66.3 g m-2 day-1, respectively. After treatment, the final effluent had an average load of 6 g m-2 day-1 for BOD5, 15 g m-2 day-1 for COD, and 51 g m-2 day-1 for TSS, indicating that the CW system achieved an average removal efficiency of 88% for BOD, 87% for COD, and 65% for TSS. The average load of total coliforms and helminthes eggs in the influent was recorded as 4 × 108 Colony-Forming Units (CFU) m-2 day-1 and 3 × 107 eggs m-2 day-1, respectively. However, the CW system demonstrated significant effectiveness in reducing microbial contamination, with an average removal efficiency of 99% for both total coliforms and helminthes eggs. The vertical flow constructed wetland system, equipped with pretreatment by sludge drying bed, has proven to be efficient in treatment of septage.
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Affiliation(s)
- Swati Singh
- Department of Environmental Science, Graphic Era (Deemed to be University), Dehradun, Uttarakhand, India
| | - Sweta Upadhyay
- Department of Environmental Science, Graphic Era (Deemed to be University), Dehradun, Uttarakhand, India
| | - Anju Rani
- Department of Microbiology, Graphic Era (Deemed to be University), Dehradun, Uttarakhand, India
| | - Pradeep Kumar Sharma
- Department of Environmental Science, Graphic Era (Deemed to be University), Dehradun, Uttarakhand, India.
| | - Janhvi Mishra Rawat
- Department of Biotechnology, Graphic Era (Deemed to be University), Dehradun, Uttarakhand, India
| | - Balwant Rawat
- School of Agriculture, Graphic Era Hill University, Dehradun, Uttarakhand, India
| | - Prashant
- Department Environmental Science, Central University of South Bihar, Gaya, Bihar, India
| | - Prosun Bhattacharya
- Department of Sustainable Development, Environmental Sciences and Engineering, KTH Royal Institute of Technology, Teknikringen 10B, 100 44, Stockholm, Sweden
- KWR Water Cycle Research Institute, Groningenhaven 7, 3433 PE, Nieuwegein, the Netherlands
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Gholipour A, Fragoso R, Duarte E, Galvão A. Sludge Treatment Reed Bed under different climates: A review using meta-analysis. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 843:156953. [PMID: 35772550 DOI: 10.1016/j.scitotenv.2022.156953] [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: 02/07/2022] [Revised: 06/20/2022] [Accepted: 06/20/2022] [Indexed: 06/15/2023]
Abstract
Sludge Treatment Reed Beds (STRBs) have been used worldwide over the past few decades. This review aims to overarchingly identify and appraise the currently available knowledge of STRB technology and discern climatic patterns through Meta-Analysis (MA). We systematically searched Google Scholar, Scopus, and Web of Science databases (up to Dec 2021) via a combination of keywords to identify English-language studies published in peer-reviewed journals. Of 142 potential articles, 73 studies met the present review objectives and inclusion criteria. Four STRB classifications including typical STRB, earthworm STRB, Sludge Treatment Electro Wetland (STEW), and earthworm STEW were found since 1990. The data and information on STRBs' configuration, operational parameters in terms of location, type of sewage sludge, study scale, Sludge Loading Rate (SLR), Dry Solid (DS), the proportion of Volatile Solid to DS (VS/DS), and their association with the feeding and resting modes were extracted from the selected articles. The analysis was focused on the interconnections between operational parameters and system efficiency for Temperate type 1 (low intensity of solar radiation), Temperate type 2 (high intensity of solar radiation), and Tropical climates. Based on MA, we found the average SLRs of 50, 70, and 101 Kg.DM.m-2.year-1 for Temperate type 1, Temperate type 2, and Tropical climates respectively, and DS during the feeding of 33 %, 35 %, and 40 %. A qualitative comparison of Arid and Polar climates was also performed given the reduced number of studies available in these climates. The volume of the sludge reduced was 60 % higher and the height of accumulated sludge was annually 2 cm in the earthworm STRBs, and STEWs compared to typical STRBs, which was 6 cm annually in Tropical climates. Correlation analysis, media characterization, list of plant species, and the removal efficiency of STRBs in the residual sludge and leachate are mentioned as well.
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Affiliation(s)
- Amir Gholipour
- LEAF - Linking Landscape, Environment, Agriculture and Food, Instituto Superior de Agronomia (ISA), University of Lisbon, Tapada da Ajuda, 1349-017 Lisbon, Portugal.
| | - Rita Fragoso
- LEAF - Linking Landscape, Environment, Agriculture and Food, Associated Laboratory TERRA, Instituto Superior de Agronomia (ISA), University of Lisbon, Tapada da Ajuda, 1349-017 Lisbon, Portugal.
| | - Elizabeth Duarte
- LEAF - Linking Landscape, Environment, Agriculture and Food, Instituto Superior de Agronomia (ISA), University of Lisbon, Tapada da Ajuda, 1349-017 Lisbon, Portugal.
| | - Ana Galvão
- CERIS, Instituto Superior Técnico (IST), University of Lisbon, Av. Rovisco Pais, 1049-001 Lisbon, Portugal.
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Jain M, Upadhyay M, Gupta AK, Ghosal PS. A review on the treatment of septage and faecal sludge management: A special emphasis on constructed wetlands. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 315:115143. [PMID: 35504184 DOI: 10.1016/j.jenvman.2022.115143] [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: 01/21/2022] [Revised: 04/18/2022] [Accepted: 04/20/2022] [Indexed: 06/14/2023]
Abstract
The global concern of the pollution of freshwater resources is associated with faecal sludge (FS) disposal, which is an inevitable component of onsite wastewater management mostly in developing countries. The difficulties with its treatment facilities lies in its higher organic content and low dewaterability of various available treatment systems. Moreover, the higher variability in characteristics and quantity of FS generated at different locations creates hindrances in designing the treatment system. Among the several treatment options, the constructed wetlands (CW) are an organic/green approach towards sanitation of FS with low cost and higher efficiency. The present study is an in-depth literature review on the quality and quantity of FS and septage (stabilized FS) in different regions attributed to the wide variability of its characteristics. This paper highlights the treatment of FS in different systems with a special emphasis on CW systems. Different mechanisms and factors affecting the FS treatment efficacy in CW, such as DO/aeration, macrophytes, substrate, CW configuration, and other environmental parameters, have been studied meticulously. The cost analysis revealed CW to be an economic system, and it can enable hybridization with other technologies to develop a complete treatment system with pronounced efficiencies. Several process modifications, such as augmentation with aeration, recirculation, micro-organisms, and earthworms, can enhance the treatment efficacies of CWs. The present review exhibited that the widely used plant species is Phragmites, and the optimum solid loading rate (SLR) range is 50-250 kg TS/m2/yr. The various factors to construct an optimized CW system for FS treatment were attempted, which may bolster the necessary guidelines for field-scale applications.
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Affiliation(s)
- Mahak Jain
- School of Water Resources, Indian Institute of Technology Kharagpur, Kharagpur, 721302, India.
| | - Maharishi Upadhyay
- School of Water Resources, Indian Institute of Technology Kharagpur, Kharagpur, 721302, India.
| | - Ashok Kumar Gupta
- Environmental Engineering Division, Department of Civil Engineering, Indian Institute of Technology Kharagpur, Kharagpur, 721302, India.
| | - Partha Sarathi Ghosal
- School of Water Resources, Indian Institute of Technology Kharagpur, Kharagpur, 721302, India.
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5
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Lin SS, Shen SL, Zhou A, Lyu HM. Assessment and management of lake eutrophication: A case study in Lake Erhai, China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 751:141618. [PMID: 33167190 DOI: 10.1016/j.scitotenv.2020.141618] [Citation(s) in RCA: 72] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 07/13/2020] [Accepted: 08/08/2020] [Indexed: 05/27/2023]
Abstract
Some wastewater sources, such as agricultural waste and runoff, and industrial sewage, can degrade water quality. This study summarises the sources and corresponding mechanisms that trigger eutrophication in lakes. Additionally, the trophic status index and water quality index (WQI) which are effective tools for evaluating the degree of eutrophication of lakes, have been discussed. This study also explores the main nutrients (nitrogen and phosphorus) driving transformations in the water body and sediment. Lake Erhai was used as a case study, and it was found to be in a mesotrophic state, with N and P co-limitation before 2006, and only P limitation since 2006. Finally, effective measures to maintain sustainable development in the watershed are proposed, along with a framework for an early warning system adopting the latest technologies (geographic information systems (GIS), remote sensing (RS)) for preventing eutrophication.
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Affiliation(s)
- Song-Shun Lin
- Department of Civil Engineering, School of Naval Architecture, Ocean, and Civil Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Shui-Long Shen
- College of Engineering, Shantou University and Key Laboratory of Intelligent Manufacturing Technology, Ministry of Education, Shantou, Guangdong 515063, China; Discipline of Civil and Infrastructure, School of Engineering, Royal Melbourne Institute of Technology (RMIT), Victoria 3001, Australia; Shanghai Key Laboratory for Digital Maintenance of Buildings and Infrastructure, Department of Civil Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.
| | - Annan Zhou
- Discipline of Civil and Infrastructure, School of Engineering, Royal Melbourne Institute of Technology (RMIT), Victoria 3001, Australia
| | - Hai-Min Lyu
- State Key Laboratory of Internet of Things for Smart City, University of Macau, Macau
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Plestenjak G, Eler K, Mihelič R, Ferlan M, Ogrinc N, Krajnc B, Vodnik D. Can additional air supply enhance decomposition processes in sludge treatment reed beds? JOURNAL OF ENVIRONMENTAL MANAGEMENT 2021; 277:111511. [PMID: 33091784 DOI: 10.1016/j.jenvman.2020.111511] [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: 05/05/2020] [Revised: 10/07/2020] [Accepted: 10/11/2020] [Indexed: 06/11/2023]
Abstract
This work was designed to investigate the influence of artificial aeration on the sludge decomposition process in mesocosm sludge treatment reed beds (STRBs). In addition to the typical STRB design, where ventilation is mainly provided by a drainage pipe, passive aeration via a "chimney" and active aeration via a blower were introduced. During the entire observation period of 1.5 years, O2 concentrations in the upper part of the filter were significantly higher in the artificially aerated beds. To determine decomposition rates, a study with decomposition bags, measurements of CO2 emissions from the STRB and isotopic partitioning of CO2 emissions were performed. The results indicate an accelerated sludge degradation process in both active and passive beds. However, this effect was limited to part of the season and could not be demonstrated by episodic measurements of CO2 efflux. The CO2 efflux showed a seasonal pattern. Average CO2 efflux was below 3.0 μmol m-2 s-1 in the winter months and reached 43 μmol m-2 s-1 in the warmer months. The low sludge load and drought period in summer 2018 resulted in an extremely low CO2 efflux in August 2018. Isotopic analyses revealed changes in decomposition dynamics for certain parts of the season, differences in contributions of sludge and plant derived CO2 to total CO2 emissions from differently aerated beds. Overall, passive aeration proved to be similarly efficient as active aeration and could therefore be considered for application in a full-scale system.
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Affiliation(s)
- G Plestenjak
- University of Ljubljana, Biotechnical Faculty, Department of Agronomy, Jamnikarjeva 101, 1000, Ljubljana, Slovenia; Limnos d.o.o., Podlimbarskega 31, 1000, Ljubljana, Slovenia.
| | - K Eler
- University of Ljubljana, Biotechnical Faculty, Department of Agronomy, Jamnikarjeva 101, 1000, Ljubljana, Slovenia
| | - R Mihelič
- University of Ljubljana, Biotechnical Faculty, Department of Agronomy, Jamnikarjeva 101, 1000, Ljubljana, Slovenia
| | - M Ferlan
- Slovenian Forestry Institute, Večna Pot 2, 1000, Ljubljana, Slovenia
| | - N Ogrinc
- Jožef Stefan Institute, Department of Environmental Sciences, Jamova 39, 1000, Ljubljana, Slovenia
| | - B Krajnc
- Jožef Stefan Institute, Department of Environmental Sciences, Jamova 39, 1000, Ljubljana, Slovenia
| | - D Vodnik
- University of Ljubljana, Biotechnical Faculty, Department of Agronomy, Jamnikarjeva 101, 1000, Ljubljana, Slovenia
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Kim B, Bel T, Bourdoncle P, Dimare J, Troesch S, Molle P. Septage unit treatment by sludge treatment reed beds for easy management and reuse: performance and design considerations. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2018; 77:279-285. [PMID: 29377813 DOI: 10.2166/wst.2017.461] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Sustainable treatment and management of fecal sludge in rural areas require adapted solutions. Rustic and simple operating processes such as sludge treatment reed beds (STRB) have been increasingly considered for this purpose. The biggest full scale (2,600 m2 of STRB) septage treatment unit in France had been built in Nègrepelisse with the final objectives of reusing treated sludge and leachates for agriculture spreading and tree irrigation, respectively. The aim of this investigation was to validate the treatment chain of this installation. The obtained field data showed firstly that the overall removal efficiencies of STRB were satisfactory and stable. Removal rates higher than 98% for chemical oxygen demand and suspended solids and a 95% for Kjeldahl nitrogen represented so far a beneficial septage treatment by STRB. The highlighted necessity of a suitable complementary leachate treatment (before tree irrigation) justified the presence of the second stage of vertical flow constructed wetland. The sludge deposit drying and mineralization efficiencies were on the right track. According to hydrotextural diagram analysis, surface deposit was however found to have high deformability probably due to the youth of the installation. An in-depth understanding of STRB system needs continuous long-term studies.
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Affiliation(s)
- Boram Kim
- Irstea, Wastewater Treatment Team, 5 rue de la Doua, 69100 Villeurbanne, France E-mail:
| | - Thomas Bel
- CCTVA, 370 Avenue du 8 Mai 1945, 82800 Nègrepelisse, France
| | | | - Jocelyne Dimare
- Adour Garonne Water Agency, 90 rue du Férétra, CS 87801, 31078 Toulouse Cedex 4, France
| | - Stéphane Troesch
- Epur Nature, 12 rue Toussaint Fléchaire, 84510 Caumont-sur-Durance, France
| | - Pascal Molle
- Irstea, Wastewater Treatment Team, 5 rue de la Doua, 69100 Villeurbanne, France E-mail:
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Gómez-Muñoz B, Larsen JD, Bekiaris G, Scheutz C, Bruun S, Nielsen S, Jensen LS. Nitrogen mineralisation and greenhouse gas emission from the soil application of sludge from reed bed mineralisation systems. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2017; 203:59-67. [PMID: 28778006 DOI: 10.1016/j.jenvman.2017.07.042] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Revised: 07/13/2017] [Accepted: 07/15/2017] [Indexed: 06/07/2023]
Abstract
A sludge treatment reed bed system (STRB) is a technology used for dewatering and stabilising sewage sludge via assisted biological mineralisation, which creates a sludge residue suitable for use as fertiliser on agricultural land. We evaluated the effect of sludge residue storage time (stabilisation time) for three STRBs on soil N mineralisation and CO2 and N2O emissions in soil. The experiment revealed that the N mineralisation rate and emissions of CO2 and N2O decreased as a function of treatment time in the STRBs. Mixed sludge residue (sludge residue subjected to different treatment times) for the three STRBs resulted in N mineralisation rates similar to the sludge residue subjected to a shorter treatment time but lower N2O emissions similar to the values of the older sludge residue. This finding reveals that combining fresh and more stabilised sludge residue ensures high N availability and reduces N2O emissions when applied to land.
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Affiliation(s)
- B Gómez-Muñoz
- Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, Thorvaldsensvej 40, DK-1871, Frederiksberg C, Denmark
| | - J D Larsen
- Department of Environmental Engineering, Technical University of Denmark, Building 113, 2800, Kgs. Lyngby, Denmark; Orbicon A/S, Ringstedvej 20, 4000, Roskilde, Denmark
| | - G Bekiaris
- Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, Thorvaldsensvej 40, DK-1871, Frederiksberg C, Denmark
| | - C Scheutz
- Department of Environmental Engineering, Technical University of Denmark, Building 113, 2800, Kgs. Lyngby, Denmark
| | - S Bruun
- Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, Thorvaldsensvej 40, DK-1871, Frederiksberg C, Denmark
| | - S Nielsen
- Orbicon A/S, Ringstedvej 20, 4000, Roskilde, Denmark.
| | - L S Jensen
- Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, Thorvaldsensvej 40, DK-1871, Frederiksberg C, Denmark
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Larsen JD, Nielsen SM, Scheutz C. Gas composition of sludge residue profiles in a sludge treatment reed bed between loadings. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2017; 76:2304-2312. [PMID: 29144288 DOI: 10.2166/wst.2017.271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Treatment of sludge in sludge treatment reed bed systems includes dewatering and mineralization. The mineralization process, which is driven by microorganisms, produces different gas species as by-products. The pore space composition of the gas species provides useful information on the biological processes occurring in the sludge residue. In this study, we measured the change in composition of gas species in the pore space at different depth levels in vertical sludge residue profiles during a resting period of 32 days. The gas composition of the pore space in the sludge residue changed during the resting period. As the resting period proceeded, atmospheric air re-entered the pore space at all depth levels. The methane (CH4) concentration was at its highest during the first part of the resting period, and then declined as the sludge residue became more dewatered and thereby aerated. In the pore space, the concentration of CH4 often exceeded the concentration of carbon dioxide (CO2). However, the total emission of CO2 from the surface of the sludge residue exceeded the total emission of CH4, suggesting that CO2 was mainly produced in the layer of newly applied sludge and/or that CO2 was emitted from the sludge residue more readily compared to CH4.
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Affiliation(s)
- Julie D Larsen
- Department of Environmental Engineering, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark; Orbicon A/S, Roskilde DK-4000, Denmark E-mail:
| | | | - Charlotte Scheutz
- Department of Environmental Engineering, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
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Kinsley C, Kennedy K, Crolla A. A combined reed bed/freezing bed technology for septage treatment and reuse in cold climate regions. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2017; 76:286-293. [PMID: 28726695 DOI: 10.2166/wst.2017.189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
A combined reed bed-freezing bed (RB-FB) technology was effective at treating septage under Canadian climatic conditions over a 5-year period with average loading rates of 82-104 kg TS/m2/y. Varying hydraulic and solid loading rates as well as the increasing sludge cake with time had little to no effect on treatment efficiency, with almost complete removal of organic matter, solids, heavy metals and nutrients. Filtrate concentrations varied significantly between the freeze-thaw and growing seasons for many parameters, although the differences were not important from a treatment or reuse perspective with filtrate quality similar to a low to medium strength domestic wastewater. The potential to reuse the filtrate as a source of irrigation water will depend upon local regulations. The dewatered sludge cake consistently met biosolids land application standards in terms of pathogen and metals content, with Escherichia coli numbers declining with time as sludge cake depth increased. A combined RB-FB technology can provide a cost-effective solution for septage management in northern rural communities with potential for beneficial reuse of both the filtrate and dewatered sludge cake.
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Affiliation(s)
- C Kinsley
- Department of Civil Engineering, University of Ottawa, 161 Louis Pasteur, Ottawa, Ontario, Canada K1N 6N5 E-mail: ; Ontario Rural Wastewater Centre, Université de Guelph - Campus d'Alfred, 31 St. Paul St., Alfred, Ontario, Canada K0B1A0
| | - K Kennedy
- Department of Civil Engineering, University of Ottawa, 161 Louis Pasteur, Ottawa, Ontario, Canada K1N 6N5 E-mail:
| | - A Crolla
- Ontario Rural Wastewater Centre, Université de Guelph - Campus d'Alfred, 31 St. Paul St., Alfred, Ontario, Canada K0B1A0
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Krithika D, Thomas AR, Iyer GR, Kranert M, Philip L. Spatio-temporal variation of septage characteristics of a semi-arid metropolitan city in a developing country. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2017; 24:7060-7076. [PMID: 28092008 DOI: 10.1007/s11356-016-8336-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2016] [Accepted: 12/25/2016] [Indexed: 06/06/2023]
Abstract
Septage is the solid sludge that accumulates in septic tanks over a period of time. Many of the developing countries in the world face the challenging task of septage management. Due to the high variability in the nature of septage, there is a need to study its physical and chemical characteristics in order to suggest a sustainable treatment methodology. The present study deals with the characterization of septage collected from different locations of Chennai city in India, in two different seasons (summer and winter). The characterization includes parameters such as solids, organics, inorganics, nutrients and heavy metals. Septage showed significant difference in concentrations of pollutants from one season to the other (p > 0.05). The average total solids concentration is found to be 1.6 times higher during winter season than compared to summer season. Average concentrations of solids were 2185 ± 1070 and 3555 ± 2935 mg/L during summer and winter, respectively. Liquid characterization of septage showed total chemical oxygen demands (COD) of 905 ± 603 mg/L (summer) and 1460 ± 1295 mg/L (winter). Similarly, average soluble biochemical oxygen demand (sBOD) was found to be 117 ± 54 mg/L during summer and 211 ± 220 mg/L during winter season. Studies also showed that septage was rich in nutrients such as total nitrogen (4-500 mg/L), ammoniacal nitrogen (2-129 mg/L), total phosphate (5-236 mg/L) and heavy metals such as copper, zinc, lead and manganese. Overall characterization indicates that the collected septage samples are highly variable in nature with respect to sources, season and locations of collection. As the septage is rich in organic matter and nutrients, it can be used as a resource like soil conditioner or as a substitute for chemical fertilizer in agriculture, after proper treatment, leading to a new evolution in sanitation.
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Affiliation(s)
- D Krithika
- Environmental and Water Resources Engineering Division, Department of Civil Engineering, IIT Madras, Chennai, 600 036, India
| | - Anu Rachel Thomas
- Environmental and Water Resources Engineering Division, Department of Civil Engineering, IIT Madras, Chennai, 600 036, India
| | - Gomathy R Iyer
- Environmental and Water Resources Engineering Division, Department of Civil Engineering, IIT Madras, Chennai, 600 036, India
| | - Martin Kranert
- Institute for Sanitary Engineering, Water Quality and Solid Waste Management, University of Stuttgart, Stuttgart, Germany
| | - Ligy Philip
- Environmental and Water Resources Engineering Division, Department of Civil Engineering, IIT Madras, Chennai, 600 036, India.
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Peruzzi E, Macci C, Doni S, Volpi M, Masciandaro G. Organic matter and pollutants monitoring in reed bed systems for sludge stabilization: a case study. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2015; 22:2447-2454. [PMID: 24859705 DOI: 10.1007/s11356-014-3054-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2013] [Accepted: 05/16/2014] [Indexed: 06/03/2023]
Abstract
In this study, results about sludge stabilization and pollutant monitoring in a reed bed system (RBSs) situated in Central Italy (Colle di Compito, 4,000 p.e.) were presented. In order to evaluate the process of sludge stabilization, parameters that highlighted the biochemical, chemical and chemico-structural properties of organic sludge matter have been followed during the entire period of operation (7 years). Moreover, the trend of heavy metals (bioavailable fractions and total content) and toxic organic compounds (LAS, NPE and DEHP) was monitored during all the period. The trend of all parameters related clearly demonstrated that sludge stabilization successfully proceeded in RBS. Moreover, through statistical analysis modelling, it is possible to determine how the stabilization process proceeded in terms of organic matter mineralization and humification, and how these processes influenced the content of pollutant compounds present in the stabilized sludges.
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Affiliation(s)
- Eleonora Peruzzi
- National Research Council - Institute of Ecosystem Study (CNR-ISE), Pisa, 56124, Italy,
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13
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Jong VSW, Tang FE. The use of palm kernel shell (PKS) as substrate material in vertical-flow engineered wetlands for septage treatment in Malaysia. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2015; 72:84-91. [PMID: 26114275 DOI: 10.2166/wst.2015.186] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
In this study, the treatment of septage (originating from septic tanks) was carried out in a pilot-scale, two-staged, vertical-flow engineered wetland (VFEW). Palm kernel shells (PKS) were incorporated as part of the VFEW's substrate (B-PKS), to compare its organic matter (OM) and nitrogen (N) removal efficiency against wetlands with only sand substrates (B-SD). The results revealed satisfactory OM removal with >90% reduction efficiencies at both wetlands B-PKS and B-SD. No increment of chemical oxygen demand (COD) concentration was observed in the effluent of B-PKS. Ammonia load removal efficiencies were comparable (>91% and 95% in wetland B-PKS and B-SD, respectively). However, nitrate accumulation was observed in the effluent of B-SD where PKS was absent. This was due to the limited denitrification in B-SD, as sand is free of carbon. A lower nitrate concentration was associated with higher COD concentration in the effluent at B-PKS. This study has shown that the use of PKS was effective in improving the N removal efficiency in engineered wetlands.
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Affiliation(s)
| | - Fu Ee Tang
- Curtin University Sarawak Campus, CDT 250, 98009 Miri, Sarawak, Malaysia E-mail:
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14
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Developing an Integrated Sustainable Sanitation System for Urban Areas: Gaza Strip Case study. ACTA ACUST UNITED AC 2015. [DOI: 10.1016/j.procir.2014.07.158] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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15
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Gagnon V, Chazarenc F, Kõiv M, Brisson J. Effect of plant species on water quality at the outlet of a sludge treatment wetland. WATER RESEARCH 2012; 46:5305-5315. [PMID: 22828383 DOI: 10.1016/j.watres.2012.07.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2012] [Revised: 06/25/2012] [Accepted: 07/06/2012] [Indexed: 06/01/2023]
Abstract
Sludge treatment wetlands are mainly used to reduce the volume of activated sludge, and the pollutants at the outlet are generally returned to the wastewater treatment plant. However, in cases where sludges are produced far from treatment plants not only must the sludge be treated, but the discharge of pollutants into the surrounding environment must also be limited. The aim of this study was to evaluate the efficiency of different plant species in optimising pollutant removal in a decentralised sludge treatment wetland. In addition, a new system design was assessed, in which the wetland was not completely drained, and a saturated layer was created using an overflow. The experimental setup consisted of 16 mesocosms in total, planted with monocultures of Phragmites australis, Typha angustifolia and Scirpus fluviatilis, and unplanted controls, each in four replicates. The experiment was conducted during the third summer of operation after setup. The system was fed with highly concentrated fish farm sludge at a load of 30 kg of total solids m(-2) yr(-1). Results showed that such wetlands were highly efficient, with removal rates between 94% and 99% for most pollutants. Planted systems generally outperformed the unplanted control, with a significantly lower mass of pollutants at the outlet of the sludge treatment wetland planted with Phragmites, followed by those with Typha and then Scirpus. The distinct influence of plant species on pollution removal was explained by the sequestration of nitrogen and phosphorus in plant tissues and by the rhizosphere effect, which enhance the biodegradation of organic matter, allowed the nitrification process and created redox conditions favourable to the sorption of phosphorus. Filtration and evapotranspiration rates played a major role in limiting the discharge of pollutants, and the impact was enhanced by the fact that the sludge treatment wetland was not completely drained.
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Affiliation(s)
- Vincent Gagnon
- Institut de Recherche en Biologie Végétale, Département de Sciences Biologiques, Université de Montréal, 4101 Sherbrooke Est, Montréal, Québec, H1X 2B2 Canada
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16
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Vincent J, Forquet N, Molle P, Wisniewski C. Mechanical and hydraulic properties of sludge deposit on sludge drying reed beds (SDRBs): influence of sludge characteristics and loading rates. BIORESOURCE TECHNOLOGY 2012; 116:161-169. [PMID: 22609671 DOI: 10.1016/j.biortech.2012.04.023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2012] [Revised: 04/05/2012] [Accepted: 04/07/2012] [Indexed: 06/01/2023]
Abstract
This work was designed to study the hydraulic properties of sludge deposit, focusing on the impact of operating conditions (i.e. loads and feeding frequencies) on air entrance (aerobic mineralization optimization) into the sludge deposit. The studied sludge deposits came from six 2m(2) pilot-scale SDRBs that had been in operation for 50 months with three different loads of 30, 50, and 70 kg of SSm(-2) y(-1). Two influents were assessed (i.e. activated sludge and septage) presenting different characteristics (i.e. pollutant contents, physical properties...). Two experimental approaches were employed based on establishing the water retention curve (capillary pressure versus volumetric water content) and the hydrotextural diagram to determine the hydraulic properties of sludge deposit. The study obtained valuable information for optimizing operating conditions, specifically for efficient management of loading frequency to optimize aerobic conditions within the sludge deposit.
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Affiliation(s)
- Julie Vincent
- Irstea, UR MALY, Wastewater Treatment Team, 3 bis quai Chauveau, CP 220, 69336 Lyon Cedex 09, France.
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17
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Uggetti E, Ferrer I, Carretero J, García J. Performance of sludge treatment wetlands using different plant species and porous media. JOURNAL OF HAZARDOUS MATERIALS 2012; 217-218:263-270. [PMID: 22480706 DOI: 10.1016/j.jhazmat.2012.03.027] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2011] [Revised: 03/07/2012] [Accepted: 03/09/2012] [Indexed: 05/31/2023]
Abstract
The aim of this study was to evaluate the dewatering and mineralisation efficiency of three sludge treatment wetlands (STW) configurations differing on plant species (Phragmites australis and Typha sp.) and filter medium (gravel and wood shavings). Sludge dewatering and mineralisation were monitored in three pilots STW for 2 years. The sludge volume was reduced by 80% in all configurations tested, the total solids (TS) increased to 16-24% TS and the volatile solids (VS) decreased to 50% VS/TS. After a resting period of three months the biosolids showed a high stabilisation (dynamic respiration index around 0.26-0.70 mgO(2)/gVS h), caused no phytotoxicity (germination index >100%), and had low heavy metals and pathogens concentrations (E. coli<240 MNP/g; absence of Salmonella). The lack of statistical significance (p>0.05) between the results obtained from the different STW configurations suggests that STW may be either planted with P. australis or Typha sp., and that wood shavings may replace gravel as filter medium.
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Affiliation(s)
- Enrica Uggetti
- GEMMA-Group of Environmental Engineering and Microbiology, Department of Hydraulic, Maritime and Environmental Engineering, Universitat Politècnica de Catalunya, BarcelonaTech, Barcelona, Spain.
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Uggetti E, Argilaga A, Ferrer I, García J. Dewatering model for optimal operation of sludge treatment wetlands. WATER RESEARCH 2012; 46:335-344. [PMID: 22118909 DOI: 10.1016/j.watres.2011.10.040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2011] [Revised: 10/01/2011] [Accepted: 10/18/2011] [Indexed: 05/31/2023]
Abstract
Sludge treatment wetlands (STW) are used as a dewatering technology in some European countries since the 80's. Although the efficiency of this technology in terms of sludge dewatering and mineralisation is well known, design and operation parameters are yet to be standardised. The aim of this study is to develop a mathematical model capable of predicting the water loss with time, in order to optimise the feeding frequency enhancing sludge dewatering and expanding the lifespan of the system. The proposed model is validated with experimental data from one pilot and two full-scale STW. The scenarios considered indicate that the optimum feeding frequency decreases with the sludge layer height. In this way, systems with a sludge layer of 20 cm, 40 cm and 80 cm (corresponding to 2, 4 and 8 years of operation), should be fed every 2.5, 10 and 30-40 days, respectively. On the other hand, evapotranspiration (ET) has no effect on the feeding frequency, although it does increase the sludge dryness from 25% to 45% (for ET of 2.5 and 14.5 mm/d in the case of 20 cm of sludge height). According to the model output, the sludge loading rate is determined as a function of evapotranspiration, feeding frequency and sludge height.
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Affiliation(s)
- Enrica Uggetti
- GEMMA, Department of Hydraulic, Maritime and Environmental Engineering, Universitat Politècnica de Catalunya, BarcelonaTech, c/Jordi Girona 1-3, Building D1, E-08034 Barcelona, Spain.
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