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Zuo Z, Zhang T, Huang X, Cen X, Lu X, Liu T, Shon HK, Zheng M. A hybrid oxidation approach for converting high-strength urine ammonia into ammonium nitrate. WATER RESEARCH X 2024; 25:100277. [PMID: 39583338 PMCID: PMC11582551 DOI: 10.1016/j.wroa.2024.100277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/18/2024] [Revised: 11/04/2024] [Accepted: 11/05/2024] [Indexed: 11/26/2024]
Abstract
Nutrient resources contained in human urine have great potential to alleviate global agricultural fertilizer demand. Microbial nitrification is a recognized strategy for stabilizing urine ammonia into ammonium nitrate, a common fertilizer worldwide, but faces a core bottleneck of process instability due to microbial inhibition. This study reports a new approach by developing a hybrid oxidation process involving three stages-microbial ammonia oxidation, chemical nitrite oxidation and microbial nitrite oxidation. Candidatus Nitrosoglobus, a γ-proteobacterial ammonia oxidizer highly tolerant to free nitrous acid, was introduced in the first stage to oxidize half of the total ammonia in the influent (8 g NH4 +-N/L) to nitrite. The nitrite was then chemically oxidized by using hydrogen peroxide via a rapid chemical reaction to form nitrate. The third stage, microbial nitrite oxidation, was employed to ensure the complete removal of residual nitrite following chemical oxidation. The overall concept demonstrated in this work showcased the robust performance of the hybrid system. Moreover, the system also had a dual advantage in achieving antimicrobial ability in the first and second stages, making treated urine a safe fertilizer.
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Affiliation(s)
- Zhiqiang Zuo
- Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW 2052, Australia
- Australian Centre for Water and Environmental Biotechnology, The University of Queensland, St Lucia, QLD 4072, Australia
- Department of Engineering, King's College London, London WC2R 2LS, UK
| | - Tianyi Zhang
- Australian Centre for Water and Environmental Biotechnology, The University of Queensland, St Lucia, QLD 4072, Australia
- Department of Civil and Environmental Engineering, Graduate School of Engineering, Tohoku University, 6-6-06 Aramaki Aza Aoba, Aoba-ku, Sendai, Miyagi 9808579, Japan
| | - Xin Huang
- Australian Centre for Water and Environmental Biotechnology, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Xiaotong Cen
- Australian Centre for Water and Environmental Biotechnology, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Xi Lu
- Australian Centre for Water and Environmental Biotechnology, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Tao Liu
- Australian Centre for Water and Environmental Biotechnology, The University of Queensland, St Lucia, QLD 4072, Australia
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong 999077, China
| | - Ho Kyong Shon
- ARC Industrial Hub for Nutrients in a Circular Economy, Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, NSW 2007, Australia
| | - Min Zheng
- Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW 2052, Australia
- Australian Centre for Water and Environmental Biotechnology, The University of Queensland, St Lucia, QLD 4072, Australia
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Yigci D, Bonventre J, Ozcan A, Tasoglu S. Repurposing Sewage and Toilet Systems: Environmental, Public Health, and Person-Centered Healthcare Applications. GLOBAL CHALLENGES (HOBOKEN, NJ) 2024; 8:2300358. [PMID: 39006062 PMCID: PMC11237177 DOI: 10.1002/gch2.202300358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Revised: 01/27/2024] [Indexed: 07/16/2024]
Abstract
Global terrestrial water supplies are rapidly depleting due to the consequences of climate change. Water scarcity results in an inevitable compromise of safe hygiene and sanitation practices, leading to the transmission of water-borne infectious diseases, and the preventable deaths of over 800.000 people each year. Moreover, almost 500 million people lack access to toilets and sanitation systems. Ecosystems are estimated to be contaminated by 6.2 million tons of nitrogenous products from human wastewater management practices. It is therefore imperative to transform toilet and sewage systems to promote equitable access to water and sanitation, improve public health, conserve water, and protect ecosystems. Here, the integration of emerging technologies in toilet and sewage networks to repurpose toilet and wastewater systems is reviewed. Potential applications of these systems to develop sustainable solutions to environmental challenges, promote public health, and advance person-centered healthcare are discussed.
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Affiliation(s)
- Defne Yigci
- School of MedicineKoç UniversityIstanbul34450Türkiye
| | - Joseph Bonventre
- Division of Renal MedicineDepartment of Medicine, Brigham and Women's HospitalHarvard Medical SchoolBostonMA02115USA
| | - Aydogan Ozcan
- Electrical and Computer Engineering DepartmentUniversity of CaliforniaLos AngelesCA90095USA
- Bioengineering DepartmentUniversity of CaliforniaLos AngelesCA90095USA
- California NanoSystems Institute (CNSI)University of CaliforniaLos AngelesCA90095USA
- Computer Science DepartmentUniversity of CaliforniaLos AngelesCA90095USA
- Department of SurgeryDavid Geffen School of MedicineUniversity of CaliforniaLos AngelesCA90095USA
| | - Savas Tasoglu
- Department of Mechanical EngineeringKoç UniversitySariyerIstanbul34450Türkiye
- Koç University Translational Medicine Research Center (KUTTAM)Koç UniversityIstanbul34450Türkiye
- Boğaziçi Institute of Biomedical EngineeringBoğaziçi UniversityIstanbul34684Turkey
- Koç University Arçelik Research Center for Creative Industries (KUAR)Koç UniversityIstanbul34450Turkey
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3
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Manga M, Muoghalu CC. Greenhouse gas emissions from on-site sanitation systems: A systematic review and meta-analysis of emission rates, formation pathways and influencing factors. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 357:120736. [PMID: 38574706 DOI: 10.1016/j.jenvman.2024.120736] [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: 01/11/2024] [Revised: 03/18/2024] [Accepted: 03/19/2024] [Indexed: 04/06/2024]
Abstract
Onsite sanitation systems (OSS) are significant sources of greenhouse gases (GHG) including carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O). While a handful of studies have been conducted on GHG emissions from OSS, systematic evaluation of literature on this subject is limited. Our systematic review and meta-analysis provides state-of-the- art information on GHG emissions from OSS and identifies novel areas for investigation. The paper analyzes GHG emission rates from different OSS, the influence of various design, operational, and environmental factors on emission rates and proffers mitigation measures. Following the Preferred Reporting Items for Systematic reviews and Meta-analysis (PRISMA) guidelines, we identified 16 articles which quantified GHG emissions from OSS. Septic tanks emit substantial amounts of CO2 and CH4 ranging from 1.74 to 398.30 g CO2/cap/day and 0.06-110.13 g CH4/cap/day, respectively, but have low N2O emissions (0.01-0.06 g N₂O/cap/day). CH4 emissions from pit latrines range from 0.77 to 20.30 g CH4/cap/day N2O emissions range from 0.76 to 1.20 gN2O/cap/day. We observed statistically significant correlations (p < 0.05) between temperature, biochemical oxygen demand, chemical oxygen demand, dissolved oxygen, storage period, and GHG emissions from OSS. However, no significant correlation (p > 0.05) was observed between soil volumetric water content and CO2 emissions. CH4 emissions (expressed as CO2 equivalents) from OSS estimated following Intergovernmental Panel for Climate Change (IPCC) guidelines were found to be seven times lower (90.99 g CO2e/cap/day) than in-situ field emission measurements (704.7 g CO2e/cap/day), implying that relying solely on IPCC guidelines may lead to underestimation of GHG emission from OSS. Our findings underscore the importance of considering local contexts and environmental factors when estimating GHG emissions from OSS. Plausible mitigation measures for GHG emissions from OSS include converting waste to biogas in anaerobic systems (e.g. biogas), applying biochar, and implementing mitigation policies that equally address inequalities in sanitation service access. Future research on GHG from OSS should focus on in-situ measurements of GHGs from pit latrines and other common OSS in developing countries, understanding the fate and transport of dissolved organics like CH4 in OSS effluents and impacts of microbial communities in OSS on GHG emissions. Addressing these gaps will enable more holistic and effective management of GHG emissions from OSS.
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Affiliation(s)
- Musa Manga
- Department of Environmental Sciences and Engineering, The Gillings School of Global Public Health, University of North Carolina at Chapel Hill, 0030 Michael Hooker Research Center, 135 Dauer Drive, Campus Box # 7431, NC 27599, Chapel Hill, NC, USA; Department of Construction Economics and Management, College of Engineering, Design, Art and Technology (CEDAT), Makerere University, P.O. Box 7062, Kampala, Uganda.
| | - Chimdi C Muoghalu
- Department of Environmental Sciences and Engineering, The Gillings School of Global Public Health, University of North Carolina at Chapel Hill, 0030 Michael Hooker Research Center, 135 Dauer Drive, Campus Box # 7431, NC 27599, Chapel Hill, NC, USA
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Oishi W, Sano D. Estimation of alkali dosage and contact time for treating human excreta containing viruses as an emergency response: a systematic review. Front Public Health 2023; 11:1286595. [PMID: 38026419 PMCID: PMC10667465 DOI: 10.3389/fpubh.2023.1286595] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Accepted: 10/31/2023] [Indexed: 12/01/2023] Open
Abstract
Water, sanitation, and hygiene provisions are essential during emergencies to prevent infectious disease outbreaks caused by improper human excreta management in settlements for people affected by natural disasters and conflicts. Human excreta disinfection is required when long-term containment in latrines is not feasible on-site. Alkali additives, including lime, are effective disinfectants for wastewater and faecal sludge containing large amounts of solid and dissolved organic matter. The aim of this study was to determine the minimum dose and contact time of alkali additives for treating virus-containing human excreta in emergency situations. We used literature data collected by searching Google Scholar and Web of Science. The date of the last search for each study was 31th May 2023. Only peer-reviewed articles that included disinfection practices in combination with quantitative data for the physicochemical data of a matrix and viral decay were selected for data extraction. Two reviewers independently collected data from each study. We extracted datasets from 14 studies that reported quantitative information about their disinfection tests, including viral decay over time, matrix types, and physicochemical properties. Three machine learning algorithms were applied to the collected dataset to determine the time required to achieve specified levels of virus inactivation under different environmental conditions. The best model was used to estimate the contact time to achieve a 3-log10 inactivation of RNA virus in wastewater and faeces. The most important variables for predicting the contact time were pH, temperature, and virus type. The estimated contact time for 3 log inactivation of RNA virus was <2 h at pH 12, which was achieved by adding 1.8 and 3.1% slaked lime to wastewater and faeces, respectively. The contact time decreased exponentially with the pH of the sludge and wastewater. In contrast, the pH of the sludge and wastewater increased linearly with the slaked lime dosage. Lime treatment is a promising measure where long-term containment in latrine is not feasible in densely populated areas, as 1 day is sufficient to inactivate viruses. The relationship we have identified between required contact time and lime dosage is useful for practitioners in determining appropriate treatment conditions of human waste.
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Affiliation(s)
- Wakana Oishi
- Department of Civil and Environmental Engineering, Graduate School of Engineering, Tohoku University, Sendai, Japan
| | - Daisuke Sano
- Department of Civil and Environmental Engineering, Graduate School of Engineering, Tohoku University, Sendai, Japan
- Department of Frontier Science for Advanced Environment, Graduate School of Environmental Studies, Tohoku University, Sendai, Japan
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5
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Guo L, Zhang Y, Osella S, Webb SM, Yang XJ, Goddard WA, Hoffmann MR. Modular Functionalization of Metal-Organic Frameworks for Nitrogen Recovery from Fresh Urine. Angew Chem Int Ed Engl 2023; 62:e202309258. [PMID: 37559432 PMCID: PMC10529058 DOI: 10.1002/anie.202309258] [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: 06/30/2023] [Revised: 08/08/2023] [Accepted: 08/09/2023] [Indexed: 08/11/2023]
Abstract
Nitrogen recovery from wastewater represents a sustainable route to recycle reactive nitrogen (Nr). It can reduce the demand of producing Nr from the energy-extensive Haber-Bosch process and lower the risk of causing eutrophication simultaneously. In this aspect, source-separated fresh urine is an ideal source for nitrogen recovery given its ubiquity and high nitrogen contents. However, current techniques for nitrogen recovery from fresh urine require high energy input and are of low efficiencies because the recovery target, urea, is a challenge to separate. In this work, we developed a novel fresh urine nitrogen recovery treatment process based on modular functionalized metal-organic frameworks (MOFs). Specifically, we employed three distinct modification methods to MOF-808 and developed robust functional materials for urea hydrolysis, ammonium adsorption, and ammonia monitoring. By integrating these functional materials into our newly developed nitrogen recovery treatment process, we achieved an average of 75 % total nitrogen reduction and 45 % nitrogen recovery with a 30-minute treatment of synthetic fresh urine. The nitrogen recovery process developed in this work can serve as a sustainable and efficient nutrient management that is suitable for decentralized wastewater treatment. This work also provides a new perspective of implementing versatile advanced materials for water and wastewater treatment.
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Affiliation(s)
- Lei Guo
- National Engineering Laboratory for Industrial Wastewater Treatment and State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai, 200237, China
- Linde Laboratories, California Institute of Technology, Pasadena, CA, 91125, USA
- Current address: Department of Civil Engineering, University of Arkansas, Fayetteville, Fayetteville, AR, 72701, USA
| | - Yi Zhang
- Linde Laboratories, California Institute of Technology, Pasadena, CA, 91125, USA
| | - Silvio Osella
- Chemical and Biological Systems Simulation Lab, Center of New Technologies, University of Warsaw, Banacha 2 C, 02-097, Warsaw, Poland
- Materials and Process Simulation Center, California Institute of Technology, Pasadena, CA, 91125, USA
| | - Samuel M Webb
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, 2575 Sand Hill Rd., Menlo Park, CA, 94025, USA
| | - Xue-Jing Yang
- National Engineering Laboratory for Industrial Wastewater Treatment and State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai, 200237, China
| | - William A Goddard
- Materials and Process Simulation Center, California Institute of Technology, Pasadena, CA, 91125, USA
| | - Michael R Hoffmann
- Linde Laboratories, California Institute of Technology, Pasadena, CA, 91125, USA
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Yan Z, Li Z, Cheng S, Wang X, Lingling Z, Zheng L, Saroj DP. Transport and deposition of solid phosphorus-based mineral particles in urine diversion systems. ENVIRONMENTAL TECHNOLOGY 2023; 44:3614-3626. [PMID: 35442161 DOI: 10.1080/09593330.2022.2068378] [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: 10/31/2021] [Accepted: 04/02/2022] [Indexed: 06/14/2023]
Abstract
The deposition of solid phosphorus-based mineral particles is a common problem in urine diversion systems, which occurs in transport systems, particularly in horizontal pipelines. In this work, particle deposition behaviour in turbulent flow in a 3D horizontal pipe was simulated by using the Euler-Lagrange method. The effects of particle diameter, particle density, particle shape factor and fluid flow velocity on particle deposition behaviour were investigated. The results showed that the deposition rate increased by 9.92%,6.88% and 6.88% with increasing particle diameter (10-90 μ m ), particle density (1400 kg/m3-2300 kg/m3), and particle shape factor (0.2-1), respectively. For particles with larger diameters (>90 μ m ) or larger density (>2300 kg/m3), the deposition rate of these particles was almost reached 100%. It was found that gravitational sedimentation was the dominant deposition mechanism in low fluid flow velocity range (0.1-0.5 m/s). As fluid flow velocity increased (>0.5 m/s), turbulent fluctuation became the dominant factor that affected particle motion behaviour, whereas the effect of gravitational sedimentation on particle deposition behaviour declined significantly, and the increase in fluid flow velocity no longer significantly affects deposition rate. It was found that the deposition rate decreased by 29.13% as the fluid flow velocity was increased from 0.1 m/s to 0.5 m/s, while the corresponding deposition rate only decreased by 14.24% when the fluid flow velocity was increased from 0.5 m/s to 2 m/s. The optimal flow velocity was found to range between 0.75 and 1.25 m/s, which may mitigate the deposition of mineral solids in urine diversion systems.
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Affiliation(s)
- Zhengxu Yan
- School of Energy and Environmental Engineering, Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing, PR People's Republic of China
| | - Zifu Li
- School of Energy and Environmental Engineering, Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing, PR People's Republic of China
| | - Shikun Cheng
- School of Energy and Environmental Engineering, Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing, PR People's Republic of China
| | - Xuemei Wang
- School of Energy and Environmental Engineering, Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing, PR People's Republic of China
| | - Zhang Lingling
- School of Energy and Environmental Engineering, Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing, PR People's Republic of China
| | - Lei Zheng
- School of Energy and Environmental Engineering, Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing, PR People's Republic of China
| | - Devendra P Saroj
- Centre for Environmental Health Engineering (CEHE), Department of Civil and Environmental Engineering, Faculty of Engineering and Physical Sciences, University of Surrey, Surrey, UK
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7
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Ersahin ME, Cicekalan B, Cengiz AI, Zhang X, Ozgun H. Nutrient recovery from municipal solid waste leachate in the scope of circular economy: Recent developments and future perspectives. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 335:117518. [PMID: 36841005 DOI: 10.1016/j.jenvman.2023.117518] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 02/11/2023] [Accepted: 02/12/2023] [Indexed: 06/18/2023]
Abstract
Holistically considering the current situation of the commercial synthetic fertilizer (CSF) market, recent global developments, and future projection studies, dependency on CSFs in agricultural production born significant risks, especially to the food security of foreign-dependent countries. The foreign dependency of countries in terms of CSFs can be reduced by the concepts such as the circular economy and resource recovery. Recently, waste streams are considered as a source in order to produce recovery-based fertilizers (RBF). RBFs produced from different waste streams can be substituted with CSFs as input for agricultural applications. Municipal solid waste leachate (MSWL) is one of the waste streams that have a high potential for RBF production. Distribution of the published papers over the years shows that this potential was noticed by more researchers in the millennium. MSWL contains a remarkable amount of nitrogen and phosphorus which are the main nutrients required for agricultural production. These nutrients can be recovered with many different methods such as microalgae cultivation, chemical precipitation, ammonia stripping, membrane separation, etc. MSWL can be generated within the different phases of municipal solid waste (MSW) management. Although it is mainly composed of landfill leachate (LL), composting plant leachate (CPL), incineration plant leachate (IPL), and transfer station leachate (TSL) should be considered as potential sources to produce RBF. This study compiles studies conducted on MSWL from the perspective of nitrogen and phosphorus recovery. Moreover, recent developments and limitations of the subject were extensively discussed and future perspectives were introduced by considering the entire MSW management. Investigated studies in this review showed that the potential of MSWL to produce RBF is significant. The outcomes of this paper will serve the countries for ensuring their food security by implementing the resource recovery concept to produce RBF. Thus, the risks born with the recent global developments could be overcome in this way besides the positive environmental outcomes of resource recovery.
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Affiliation(s)
- Mustafa Evren Ersahin
- Istanbul Technical University, Civil Engineering Faculty, Environmental Engineering Department, Ayazaga Campus, Maslak, 34469, Istanbul, Turkey; National Research Center on Membrane Technologies, Istanbul Technical University, Ayazaga Campus, Maslak, 34469, Istanbul, Turkey.
| | - Busra Cicekalan
- Istanbul Technical University, Civil Engineering Faculty, Environmental Engineering Department, Ayazaga Campus, Maslak, 34469, Istanbul, Turkey
| | - Ali Izzet Cengiz
- Istanbul Technical University, Civil Engineering Faculty, Environmental Engineering Department, Ayazaga Campus, Maslak, 34469, Istanbul, Turkey
| | - Xuedong Zhang
- Jiangsu Key Laboratory of Anaerobic Biotechnology, School of Environmental and Civil Engineering, Jiangnan University, Wuxi, 214122, China
| | - Hale Ozgun
- Istanbul Technical University, Civil Engineering Faculty, Environmental Engineering Department, Ayazaga Campus, Maslak, 34469, Istanbul, Turkey; National Research Center on Membrane Technologies, Istanbul Technical University, Ayazaga Campus, Maslak, 34469, Istanbul, Turkey
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8
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Kachoria P, Sasidaran S, Welling CM, Rosario P, Zhou J, Chakrabarty K, Gründl H, Kristoferitsch L, Grego S. Sensor-based evaluation of a Urine Trap toilet in a shared bathroom. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 857:159178. [PMID: 36202366 PMCID: PMC9742848 DOI: 10.1016/j.scitotenv.2022.159178] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Revised: 09/03/2022] [Accepted: 09/28/2022] [Indexed: 06/16/2023]
Abstract
Urine diversion in a No-Mix Toilet is a promising approach for sustainable fertilizers and reduction of the nutrient load for wastewater treatment; however, user adoption remains a challenge. This study evaluates the Urine Trap, a passive No-Mix toilet design based on the teapot effect, wherein the urine stream inlet is invisible to the user and therefore it does not impact the user experience for increased adoption. This study evaluated the nutrient separation performance of a Urine Trap flush toilet in a bathroom shared by women in two sites in India. Over three different testing periods, 841 uses of this squat plate were recorded in 50 days. Analytical measurements found 36 % separation efficiency for total nitrogen (TN). While effective, the Urine Trap under test by users did not yield a 70-80 % TN separation efficiency observed under engineering characterization. High temporal resolution data from sensors on waste collection tanks, the opening of the bathroom door, and cleansing water flow were used to gain insights into hygiene practices. The data showed a frequent habit of wetting the squat plate during physiological excretion, a hygienic practice that eases cleaning but degrades the teapot separation effect of the Urine Trap design. By using sensors, we demonstrate a method to non-invasively gain quantitative insights into hygiene practices to inform sanitation technologies deployment strategies for improved outcomes.
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Affiliation(s)
| | | | - Claire M Welling
- Center for Water, Sanitation, Hygiene and Infectious Disease (WASH-AID), Department of Electrical and Computer Engineering, Duke University, Durham, NC, USA
| | | | - Jin Zhou
- Department of Electrical and Computer Engineering, Duke University, Durham, NC, USA
| | | | - Harald Gründl
- EOOS Design GmbH, Zelinkagasse 2/6, 1010 Vienna, Austria
| | | | - Sonia Grego
- Center for Water, Sanitation, Hygiene and Infectious Disease (WASH-AID), Department of Electrical and Computer Engineering, Duke University, Durham, NC, USA.
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9
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Sniatala B, Kurniawan TA, Sobotka D, Makinia J, Othman MHD. Macro-nutrients recovery from liquid waste as a sustainable resource for production of recovered mineral fertilizer: Uncovering alternative options to sustain global food security cost-effectively. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 856:159283. [PMID: 36208738 DOI: 10.1016/j.scitotenv.2022.159283] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 09/27/2022] [Accepted: 10/02/2022] [Indexed: 06/16/2023]
Abstract
Global food security, which has emerged as one of the sustainability challenges, impacts every country. As food cannot be generated without involving nutrients, research has intensified recently to recover unused nutrients from waste streams. As a finite resource, phosphorus (P) is largely wasted. This work critically reviews the technical applicability of various water technologies to recover macro-nutrients such as P, N, and K from wastewater. Struvite precipitation, adsorption, ion exchange, and membrane filtration are applied for nutrient recovery. Technological strengths and drawbacks in their applications are evaluated and compared. Their operational conditions such as pH, dose required, initial nutrient concentration, and treatment performance are presented. Cost-effectiveness of the technologies for P or N recovery is also elaborated. It is evident from a literature survey of 310 published studies (1985-2022) that no single technique can effectively and universally recover target macro-nutrients from liquid waste. Struvite precipitation is commonly used to recover over 95 % of P from sludge digestate with its concentration ranging from 200 to 4000 mg/L. The recovered precipitate can be reused as a fertilizer due to its high content of P and N. Phosphate removal of higher than 80 % can be achieved by struvite precipitation when the molar ratio of Mg2+/PO43- ranges between 1.1 and 1.3. The applications of artificial intelligence (AI) to collect data on critical parameters control optimization, improve treatment effectiveness, and facilitate water utilities to upscale water treatment plants. Such infrastructure in the plants could enable the recovered materials to be reused to sustain food security. As nutrient recovery is crucial in wastewater treatment, water treatment plant operators need to consider (1) the costs of nutrient recovery techniques; (2) their applicability; (3) their benefits and implications. It is essential to note that the treatment cost of P and/or N-laden wastewater depends on the process applied and local conditions.
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Affiliation(s)
- Bogna Sniatala
- Faculty of Civil and Environmental Engineering, Gdańsk University of Technology, Gdańsk, Poland
| | - Tonni Agustiono Kurniawan
- Advanced Membrane Technology Research Centre (AMTEC), Faculty of Chemical and Energy Engineering, Universiti Teknologi Malaysia, 81310 Skudai, Johor, Malaysia.
| | - Dominika Sobotka
- Faculty of Civil and Environmental Engineering, Gdańsk University of Technology, Gdańsk, Poland
| | - Jacek Makinia
- Faculty of Civil and Environmental Engineering, Gdańsk University of Technology, Gdańsk, Poland.
| | - Mohd Hafiz Dzarfan Othman
- Advanced Membrane Technology Research Centre (AMTEC), Faculty of Chemical and Energy Engineering, Universiti Teknologi Malaysia, 81310 Skudai, Johor, Malaysia
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10
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A novel mixing mechanism for effective stabilisation of urea in urinals for subsequent nutrient recovery. SOUTH AFRICAN JOURNAL OF CHEMICAL ENGINEERING 2022. [DOI: 10.1016/j.sajce.2022.07.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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11
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Riechmann ME, Ndwandwe B, Greenwood EE, Reynaert E, Morgenroth E, Udert KM. On-site urine treatment combining Ca(OH) 2 dissolution and dehydration with ambient air. WATER RESEARCH X 2021; 13:100124. [PMID: 34917915 PMCID: PMC8645517 DOI: 10.1016/j.wroa.2021.100124] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2021] [Revised: 09/22/2021] [Accepted: 10/04/2021] [Indexed: 05/28/2023]
Abstract
We present the results of three field tests and three laboratory tests of a new physical-chemical urine treatment system, which can recover all nutrients, while pathogens are inactivated. The system consists of two steps. In the first reactor, biological processes including urea hydrolysis are prevented by mixing fresh urine with calcium hydroxide (Ca(OH)2). Due to the high pH value and the high availability of calcium, phosphate can be recovered by precipitation. The high pH value also fosters the inactivation of microorganisms, including pathogens. In the second reactor, water is evaporated at low energy consumption by blowing unheated ambient air over the stabilized urine. Stabilization in the first reactor was successful in all field and laboratory tests. The pH value remained between 12 and 13, except for short dips due to shortages of Ca(OH)2. Nearly all phosphorus (92-96%) precipitated and could be recovered as calcium phosphate in the first reactor, while nitrogen and potassium overflowed with the urine into the evaporation reactor. The efficiency of the second treatment step was very different for field and laboratory experiments and depended on the duration of the experiment. During a four-day laboratory test, nitrogen recovery was 98%. In contrast, nitrogen recovery was only around 20% in the long-term field experiments. The high nitrogen losses occurred, because biological urea hydrolysis was not inhibited anymore, when the pH value in the second reactor decreased due to the dissolution of high amounts of carbon dioxide from the ambient air. Potassium was not subject to any significant loss, and the measured recovery in the solid evaporation product was 98%. Evaporation rates ranged between 50 g m-2 h-1 (RH = 82±13%, T = 12±6°C) and 130 g m-2 h-1 (RH = 60±19%, T = 24±5°C) in the three field tests. Apart from some disturbances due to low supply of Ca(OH)2, the urine module functioned without any substantial failures and was simple to maintain. The minimum consumption of Ca(OH)2 at full capacity was 6 g·L-1 urine and the electricity demand was 150 Wh kg-1 water evaporated from urine, resulting in operational costs of 0.05 EUR pers-1 d-1.
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Affiliation(s)
- Michel E. Riechmann
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600 Dübendorf, Switzerland
| | | | - Esther E. Greenwood
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600 Dübendorf, Switzerland
| | - Eva Reynaert
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600 Dübendorf, Switzerland
- ETH Zürich, Institute of Environmental Engineering, 8093 Zürich, Switzerland
| | - Eberhard Morgenroth
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600 Dübendorf, Switzerland
- ETH Zürich, Institute of Environmental Engineering, 8093 Zürich, Switzerland
| | - Kai M. Udert
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600 Dübendorf, Switzerland
- ETH Zürich, Institute of Environmental Engineering, 8093 Zürich, Switzerland
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12
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Larsen TA, Riechmann ME, Udert KM. State of the art of urine treatment technologies: A critical review. WATER RESEARCH X 2021; 13:100114. [PMID: 34693239 PMCID: PMC8517923 DOI: 10.1016/j.wroa.2021.100114] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Revised: 07/15/2021] [Accepted: 08/14/2021] [Indexed: 05/26/2023]
Abstract
Over the last 15 years, urine treatment technologies have developed from lab studies of a few pioneers to an interesting innovation, attracting attention from a growing number of process engineers. In this broad review, we present literature from more than a decade on biological, physical-chemical and electrochemical urine treatment processes. Like in the first review on urine treatment from 2006, we categorize the technologies according to the following objectives: stabilization, volume reduction, targeted N-recovery, targeted P-recovery, nutrient removal, sanitization, and handling of organic micropollutants. We add energy recovery as a new objective, because extensive work has been done on electrochemical energy harvesting, especially with bio-electrochemical systems. Our review reveals that biological processes are a good choice for urine stabilization. They have the advantage of little demand for chemicals and energy. Due to instabilities, however, they are not suited for bathroom applications and they cannot provide the desired volume reduction on their own. A number of physical-chemical treatment technologies are applicable at bathroom scale and can provide the necessary volume reduction, but only with a steady supply of chemicals and often with high demand for energy and maintenance. Electrochemical processes is a recent, but rapidly growing field, which could give rise to exciting technologies at bathroom scale, although energy production might only be interesting for niche applications. The review includes a qualitative assessment of all unit processes. A quantitative comparison of treatment performance was not the goal of the study and could anyway only be done for complete treatment trains. An important next step in urine technology research and development will be the combination of unit processes to set up and test robust treatment trains. We hope that the present review will help guide these efforts to accelerate the development towards a mature technology with pilot scale and eventually full-scale implementations.
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Affiliation(s)
- Tove A. Larsen
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600 Dübendorf, Switzerland
| | - Michel E. Riechmann
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600 Dübendorf, Switzerland
| | - Kai M. Udert
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600 Dübendorf, Switzerland
- ETH Zürich, Institute of Environmental Engineering, 8093 Zürich, Switzerland
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13
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Marepula H, Courtney C, Randall D. Urea recovery from stabilized urine using a novel ethanol evaporation and recrystallization process. CHEMICAL ENGINEERING JOURNAL ADVANCES 2021. [DOI: 10.1016/j.ceja.2021.100174] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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14
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Kurniawan TA, Singh D, Avtar R, Othman MHD, Hwang GH, Albadarin AB, Rezakazemi M, Setiadi T, Shirazian S. Resource recovery from landfill leachate: An experimental investigation and perspectives. CHEMOSPHERE 2021; 274:129986. [PMID: 33979934 DOI: 10.1016/j.chemosphere.2021.129986] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2020] [Revised: 01/12/2021] [Accepted: 02/09/2021] [Indexed: 06/12/2023]
Abstract
This work investigates the performances of coconut shell waste-based activated carbon (CSWAC) adsorption in batch studies for removal of ammoniacal nitrogen (NH3-N) and refractory pollutants (as indicated by decreasing COD concentration) from landfill leachate. To valorize unused resources, coconut shell, recovered and recycled from agricultural waste, was converted into activated carbon, which can be used for leachate treatment. The ozonation of the CSWAC was conducted to enhance its removal performance for target pollutants. The adsorption mechanisms of refractory pollutants by the adsorbent are proposed. Perspectives on nutrient recovery technologies from landfill leachate from the view-points of downstream processing are presented. Their removal efficiencies for both recalcitrant compounds and ammoniacal nitrogen were compared to those of other techniques reported in previous work. It is found that the ozonated CSWAC substantially removed COD (i.e. 76%) as well as NH3-N (i.e. 75%), as compared to the CSWAC without pretreatment (i.e. COD: 44%; NH3-N: 51%) with NH3-N and COD concentrations of 2750 and 8500 mg/L, respectively. This reveals the need of ozonation for the adsorbent to improve its performance for the removal of COD and NH3-N at optimized reactions: 30 g/L of CSWAC, pH 8, 200 rpm of shaking speed and 20 min of reaction time. Nevertheless, treatment of the leachate samples using the ozonated CSWAC alone was still unable to result in treated effluents that could meet the COD and NH3-N discharge standards below 200 and 5 mg/L, respectively, set by legislative requirements. This reveals that another treatment is necessary to be undertaken to comply with the requirement of their effluent limit.
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Affiliation(s)
| | - Deepak Singh
- Department of Geography and Resource Management, Chinese University of Hong Kong, Hong Kong
| | - Ram Avtar
- Faculty of Environmental Earth Sciences, Hokkaido University, Sapporo, 060-0810, Japan
| | - Mohd Hafiz Dzarfan Othman
- Advanced Membrane Technology Research Centre (AMTEC), School of Chemical and Energy Engineering, University Teknologi Malaysia, 81310, Skudai, Johor, Malaysia
| | - Goh Hui Hwang
- School of Electrical Engineering, Guangxi University, Nanning, Guangxi, PR China
| | - Ahmad B Albadarin
- Department of Chemical Sciences, Bernal Institute, University of Limerick, Limerick, Ireland
| | - Mashallah Rezakazemi
- Faculty of Chemical and Materials Engineering, Shahrood University of Technology, Shahrood, Iran
| | - Tjandra Setiadi
- Center for Environmental Studies, Bandung Institute of Technology, Bandung, 40135, Indonesia
| | - Saeed Shirazian
- Institute of Research and Development, Duy Tan University, Da Nang, 550000, Viet Nam; Faculty of Environmental and Chemical Engineering, Duy Tan University, Da Nang, 550000, Viet Nam; Laboratory of Computational Modeling of Drugs, South Ural State University, 454080, Chelyabinsk, Russia
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15
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De Paepe J, Clauwaert P, Gritti MC, Ganigué R, Sas B, Vlaeminck SE, Rabaey K. Electrochemical In Situ pH Control Enables Chemical-Free Full Urine Nitrification with Concomitant Nitrate Extraction. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:8287-8298. [PMID: 34086451 DOI: 10.1021/acs.est.1c00041] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Urine is a valuable resource for nutrient recovery. Stabilization is, however, recommended to prevent urea hydrolysis and the associated risk for ammonia volatilization, uncontrolled precipitation, and malodor. This can be achieved by alkalinization and subsequent biological conversion of urea and ammonia into nitrate (nitrification) and organics into CO2. Yet, without pH control, the extent of nitrification is limited as a result of insufficient alkalinity. This study explored the feasibility of an integrated electrochemical cell to obtain on-demand hydroxide production through water reduction at the cathode, compensating for the acidification caused by nitritation, thereby enabling full nitrification. To deal with the inherent variability of the urine influent composition and bioprocess, the electrochemical cell was steered via a controller, modulating the current based on the pH in the bioreactor. This provided a reliable and innovative alternative to base addition, enabling full nitrification while avoiding the use of chemicals, the logistics associated with base storage and dosing, and the associated increase in salinity. Moreover, the electrochemical cell could be used as an in situ extraction and concentration technology, yielding an acidic concentrated nitrate-rich stream. The make-up of the end product could be tailored by tweaking the process configuration, offering versatility for applications on Earth and in space.
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Affiliation(s)
- Jolien De Paepe
- Center for Microbial Ecology and Technology (CMET), Department of Biotechnology, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Gent, Belgium
- Departament d'Enginyeria Química, Biològica I Ambiental, Escola d'Enginyeria, Universitat Autònoma de Barcelona, Bellaterra 08193 Barcelona, Spain
- Centre for Advanced Process Technology and Urban Resource Efficiency (CAPTURE), Belgium, Ghent University, 9000 Gent, Belgium
| | - Peter Clauwaert
- Center for Microbial Ecology and Technology (CMET), Department of Biotechnology, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Gent, Belgium
- Centre for Advanced Process Technology and Urban Resource Efficiency (CAPTURE), Belgium, Ghent University, 9000 Gent, Belgium
| | - Maria Celeste Gritti
- Center for Microbial Ecology and Technology (CMET), Department of Biotechnology, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Gent, Belgium
| | - Ramon Ganigué
- Center for Microbial Ecology and Technology (CMET), Department of Biotechnology, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Gent, Belgium
- Centre for Advanced Process Technology and Urban Resource Efficiency (CAPTURE), Belgium, Ghent University, 9000 Gent, Belgium
| | - Benedikt Sas
- Department of Food Quality and Food Safety, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, 9000 Gent, Belgium
| | - Siegfried E Vlaeminck
- Centre for Advanced Process Technology and Urban Resource Efficiency (CAPTURE), Belgium, Ghent University, 9000 Gent, Belgium
- Research Group of Sustainable Energy, Air and Water Technology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerpen, Belgium
| | - Korneel Rabaey
- Center for Microbial Ecology and Technology (CMET), Department of Biotechnology, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Gent, Belgium
- Centre for Advanced Process Technology and Urban Resource Efficiency (CAPTURE), Belgium, Ghent University, 9000 Gent, Belgium
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16
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Drangert JO. Urban water and food security in this century and beyond: Resource-smart cities and residents. AMBIO 2021; 50:679-692. [PMID: 33001342 PMCID: PMC7882668 DOI: 10.1007/s13280-020-01373-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/07/2019] [Revised: 05/12/2020] [Accepted: 07/18/2020] [Indexed: 06/11/2023]
Abstract
The urban world population will increase from 3 to 8.5 thousand million in the 21st century. Cities become hot spots of both demand for water and global food and for disposed used water and nutrients. Sustainability requires that resource flows through our cities are co-managed and connected to agriculture. Reduced use of harmful chemicals in consumer products facilitates treatment to a quality that allows reuse/recycling of water and nutrients. A solid and liquid waste hierarchy can assist in ordering measures. A novel flexible water balance can guide city infrastructure and keep toilet water separate. New water-saving equipment can substantially reduce water use without losing personal comfort. The combination of these new approaches ascertains access to safe urban water, and that recovered nutrients from cities can substitute half of chemical fertilisers needed in food production. Now, thousands of new cities and suburbs provide unique opportunities to develop resource-smart and sustainable flows.
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Affiliation(s)
- Jan-Olof Drangert
- Department of Water and Environmental Studies, Linköping University, Linköping, Sweden.
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17
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Lv Y, Li Z, Zhou X, Cheng S, Zheng L. Stabilization of source-separated urine by heat-activated peroxydisulfate. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 749:142213. [PMID: 33370919 PMCID: PMC7607252 DOI: 10.1016/j.scitotenv.2020.142213] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 08/29/2020] [Accepted: 09/03/2020] [Indexed: 06/12/2023]
Abstract
Source-separated urine is an attractive fertilizer due to its high nutrient content, but the rapidly hydrolysis of urea leads to ammonia volatilization and other environmental problems. Urine stabilization, which meanly means preventing enzymatic urea hydrolysis, receives increasing attention. Accordingly, this study developed a technique to stabilize fresh urine by heat-activated peroxydisulfate (PDS). The effect of three crucial parameters, including temperature (55, 62.5, and 70 °C), heat-activated time (1, 2, and 3 h), and PDS concentration (10, 30, and 50 mM) that affect the activation of PDS in urine stabilization were investigated. Nitrogen in fresh urine treated with 50 mM PDS at 62.5 °C for 3 h existed mainly in the form of urea for more than 22 days at 25 °C. Moreover, the stabilized urine could remain stable and resist second contamination by continuous and slow pH decrease due to PDS decomposition during storage. Less than 8% of nitrogen loss in stabilized urine was detected during the experiment. The investigation of nitrogen transformation pathway demonstrated that urea was decomposed into NH4+ by heat-activated PDS and further oxidized to NO2- and NO3-. The nitrogen loss during treatment occurred via heat-driven ammonia volatilization and N2 emission produced by synproportionation of NO2- and NH4+ under acid and thermal conditions. Overall, this study investigated an efficient approach of urine stabilization to improve urine utilization in terms of nutrient recovery.
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Affiliation(s)
- Yaping Lv
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, PR China; Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing 100083, PR China
| | - Zifu Li
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, PR China; Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing 100083, PR China.
| | - Xiaoqin Zhou
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, PR China; Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing 100083, PR China
| | - Shikun Cheng
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, PR China; Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing 100083, PR China
| | - Lei Zheng
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, PR China; Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing 100083, PR China
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18
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Saliu TD, Ali J, Ololade IA, Oladoja NA. Preparation and characterization of a decentralized modular yellow water nutrient recovery system. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2020; 276:111345. [PMID: 32920459 DOI: 10.1016/j.jenvman.2020.111345] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 09/01/2020] [Accepted: 09/02/2020] [Indexed: 06/11/2023]
Abstract
The peculiarity of human urine as a resource, in terms of ethical and cultural considerations, and human perception, demands the development of a highly decentralized modular system, to enable the feasibility of the emerging concept of nutrient recovery in this regard. Consequently, a modular reactor, with packed bed of granular Gastropod shell (GS) was constructed for nutrient recovery from yellow water and the operational parameters were derived in simulated and pilot studies. Prior to the design of the modular reactor, both the raw and calcined GS were screened in a batch reactor for nutrient fraction recovery (i.e. total phosphorus (TP) and total nitrogen (TN)). The TP recovery was more favorable than the TN, but the TN recovery was the rate determining step. Despite the low TN capture efficiency of the reactor, the hydrolysis of the urea fraction that promotes nitrogen loss from yellow water was greatly impeded. The system showed higher selectivity for the nutrient fraction than the other constituents of the human urine, as manifested in the high residual COD and creatinine values in the treated yellow water. The volume of yellow water treated and the nutrient recovery capacity of the modular reactor were HRT dependent. A diminution in the nutrient recovery efficiency was observed in the pilot study, when compared with the simulated studies of the same HRT.
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Affiliation(s)
- T D Saliu
- Hydrochemistry Research Laboratory, Department of Chemical Sciences, Adekunle Ajasin University, Akungba Akoko, Nigeria
| | - J Ali
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - I A Ololade
- Department of Chemical Sciences, Adekunle Ajasin University, Akungba Akoko, Nigeria
| | - N A Oladoja
- Hydrochemistry Research Laboratory, Department of Chemical Sciences, Adekunle Ajasin University, Akungba Akoko, Nigeria.
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19
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Saetta D, Zheng C, Leyva C, Boyer TH. Impact of acetic acid addition on nitrogen speciation and bacterial communities during urine collection and storage. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 745:141010. [PMID: 32738689 DOI: 10.1016/j.scitotenv.2020.141010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 07/07/2020] [Accepted: 07/14/2020] [Indexed: 06/11/2023]
Abstract
The rate of urea hydrolysis in nonwater urinals is influenced by the volume of urination events and the frequency of urinal use. Inhibition of urea hydrolysis with acetic acid addition has been demonstrated at the laboratory scale but it was not able to fully represent the conditions of a real restroom with real urine collection. The goal of this study was to understand the effects of acid addition for control of urea hydrolysis on nutrient concentrations and bacterial communities in human urine during collection and storage. Three control logics were used to determine the schedule of acid addition: (i) acid addition after every urination event, (ii) acid addition during periods of high building occupancy, and (iii) acid addition during periods of low building occupancy. Wifi logins were used to approximate building occupancy and to create the control logics used in the study. All three control logics were able to inhibit urea hydrolysis. The bacterial communities were identified to determine the impact of acid addition on the community structure. The collection of urine by nonwater urinals alone did not reduce the presence of enteric bacteria commonly found when collecting urine with urine-diverting toilets. Acid addition reduced the community diversity and created conditions for higher relative abundances of the order Enterobacteriales. Finally, results from stored acidified urine showed that urea hydrolysis inhibition is reversible and is influenced by the amount of acid added at the urinal. The amount of acid added can influence the rate of hydrolysis in the storage tanks and can be used to select for urea- or ammonia-nitrogen for nutrient recovery. This study is the first of its kind to inhibit urea hydrolysis in nonwater urinals in a real restroom with real urine, and is the first to identify the bacterial communities in urine collected solely with nonwater urinals.
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Affiliation(s)
- Daniella Saetta
- Swette Center for Environmental Biotechnology, The Biodesign Institute at Arizona State University, P.O. Box 875701, Tempe, AZ 85287, USA; School of Sustainable Engineering and the Built Environment (SSEBE), Arizona State University, P.O. Box 873005, Tempe, AZ 85287-3005, USA.
| | - Chenwei Zheng
- Swette Center for Environmental Biotechnology, The Biodesign Institute at Arizona State University, P.O. Box 875701, Tempe, AZ 85287, USA; School of Sustainable Engineering and the Built Environment (SSEBE), Arizona State University, P.O. Box 873005, Tempe, AZ 85287-3005, USA
| | - Carlos Leyva
- Swette Center for Environmental Biotechnology, The Biodesign Institute at Arizona State University, P.O. Box 875701, Tempe, AZ 85287, USA; ASU Future H(2)O, Office of Knowledge Enterprise Development, Arizona State University, P.O. Box 877205, Tempe, AZ 85287-7205, USA
| | - Treavor H Boyer
- Swette Center for Environmental Biotechnology, The Biodesign Institute at Arizona State University, P.O. Box 875701, Tempe, AZ 85287, USA; School of Sustainable Engineering and the Built Environment (SSEBE), Arizona State University, P.O. Box 873005, Tempe, AZ 85287-3005, USA
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20
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Patel A, Mungray AA, Mungray AK. Technologies for the recovery of nutrients, water and energy from human urine: A review. CHEMOSPHERE 2020; 259:127372. [PMID: 32599379 DOI: 10.1016/j.chemosphere.2020.127372] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2020] [Revised: 05/15/2020] [Accepted: 06/08/2020] [Indexed: 06/11/2023]
Abstract
The global demand for a constant supply of fertilizer is increasing with the booming of the population. Nowadays more focus is given to the recovery and reuse of the nutrients rather than synthesis of the fertilizer from chemicals. Human urine is the best available resource for the primary macronutrients (Nitrogen, Phosphorus and Potassium) for the fertilizer as it contains 10-12 g/L nitrogen, 0.1-0.5 g/L phosphorous and 1.0-2.0 g/L potassium. For the recovery of these nutrients from human urine, various technologies are available which requires source separation and treatment. . In this review, a wide range of the technologies for the treatment of source-separated human urine are covered and discussed in detail. This review has categorized the technologies based on the recovery of nutrients, energy, and water from human urine. Among the various technologies available, Bio-electrochemical technologies are environmental friendly and recovers energy along with the nutrients. Forward Osmosis is the best available technology for the water recovery and for concentrating the nutrients in urine, without or minimal consumption of energy. However, experimental work in this technology is at its prior stage. A single technology is still not sufficient to recover nutrients, water and energy. Therefore, integration of two or more technologies seems essential.
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Affiliation(s)
- Asfak Patel
- Chemical Engineering Department, Sardar Vallabhbhai National Institute of Technology, Surat, Gujarat, India.
| | - Alka A Mungray
- Chemical Engineering Department, Sardar Vallabhbhai National Institute of Technology, Surat, Gujarat, India.
| | - Arvind Kumar Mungray
- Chemical Engineering Department, Sardar Vallabhbhai National Institute of Technology, Surat, Gujarat, India.
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21
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Abstract
Global deposits of concentrated phosphates, which are a necessary source for the production of phosphate fertilizers, are limited. These reserves keep getting thinner, and every day, large amounts of phosphorus end up in watercourses. In this study, we verified that modified biochar (saturated with FeCl3 solution and then neutralized with NaOH solution) can adsorb significant amounts of phosphorus from wastewater. Moreover, the agrochemical qualities of sludge water from a municipal wastewater treatment plant, struvite, phosphorus-saturated biochar, and iron(III) phosphate from a reused biochar filter were tested in this study. We determined the amount of mobile phosphorus as well as the amount of extractable phosphorus and its five fractions. It was found that modified biochar can hold one-third of the phosphorus amount contained in the commonly used agricultural fertilizer simple superphosphate (1 × 105 g of modified biochar captures up to 2.79 × 103 g of P). Moreover, plants can more easily access phosphorus biochar fractions than struvite, which is formed spontaneously during sludge management. The results of this research prove that the proposed method of recycling phosphorus from wastewater can be applied in technological practice.
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Simha P, Lalander C, Nordin A, Vinnerås B. Alkaline dehydration of source-separated fresh human urine: Preliminary insights into using different dehydration temperature and media. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 733:139313. [PMID: 32446074 DOI: 10.1016/j.scitotenv.2020.139313] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 05/06/2020] [Accepted: 05/07/2020] [Indexed: 06/11/2023]
Abstract
For sanitation systems aiming at recycling nutrients, separately collecting urine at source is desirable as urine contains most of the nutrients in wastewater. However, reducing the volume of the collected urine and recovering majority of its nutrients is necessary, as this improves the transportability and the end-application of urine-based fertilisers. In this study, we present an innovative method, alkaline dehydration, for treating fresh human urine into a nutrient-rich dry solid. Our aim was to investigate whether fresh urine (pH < 7) added to five different alkaline media (pH > 11) could be dehydrated at elevated temperatures (50 and 60 °C) with minimal loss of urea, urine's principal nitrogen compound. We found that it was possible to concentrate urine 48 times, yielding dry end-products with high fertiliser value: approximately, 10% N, 1% P, and 4% K. We monitored the physicochemical properties and the composition of various dehydration media to provide useful insights into their suitability for dehydrating urine. We demonstrated that it is possible to recover >90% nitrogen when treating fresh urine by alkaline dehydration by inhibiting the enzymatic hydrolysis of urea at elevated pH and minimising the chemical hydrolysis of urea with high urine dehydration rates.
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Affiliation(s)
- Prithvi Simha
- Swedish University of Agricultural Sciences, Department of Energy and Technology, Box 7032, SE-750 07 Uppsala, Sweden.
| | - Cecilia Lalander
- Swedish University of Agricultural Sciences, Department of Energy and Technology, Box 7032, SE-750 07 Uppsala, Sweden
| | - Annika Nordin
- Swedish University of Agricultural Sciences, Department of Energy and Technology, Box 7032, SE-750 07 Uppsala, Sweden
| | - Björn Vinnerås
- Swedish University of Agricultural Sciences, Department of Energy and Technology, Box 7032, SE-750 07 Uppsala, Sweden
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23
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Guadie A, Belay A, Liu W, Yesigat A, Hao X, Wang A. Rift Valley Lake as a potential magnesium source to recover phosphorus from urine. ENVIRONMENTAL RESEARCH 2020; 184:109363. [PMID: 32209497 DOI: 10.1016/j.envres.2020.109363] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 03/06/2020] [Accepted: 03/08/2020] [Indexed: 06/10/2023]
Abstract
Phosphorus recovery from urine is a sustainable approach. However, the challenge of this process is the accessibility of economically feasible magnesium sources. This study aimed to investigate the potential of low-cost Rift Valley Lake magnesium (RVL-Mg) source for phosphorus recovery from urine, where data is deficient in the source area. The effect of various operational conditions such as storage, Mg:P ratio (0.8-2.0), pH (5.5-10.5), mixing speed (30-180 rpm), urease enzyme addition (50-700 μL), urine dilution (0.11-9.0) and Ca:Mg ratio (0.3-2.5) was investigated. Under optimum operating conditions (M:P = 1.6, pH = 9, urease enzyme = 500 μL, mixing speed = 120 rpm, 60 min precipitation), the phosphorus removal efficiencies were >96% for actual and >98% for synthetic urine. During storage, spontaneous phosphorus losses were observed from synthetic (24.0%) and actual (32.0%) hydrolyzed urine due to precipitation with calcium and magnesium. The phosphorus recovery efficiency was reduced at higher (0.11:1) and lower (9:1) urine to RVL-Mg dilution, which is related to lower supersaturation of phosphorus and magnesium ions, respectively. Addition of calcium did not affect phosphorus removal efficiency, but the effect was significant on crystal product. With low (<1.0) Ca:Mg ratio, the crystal chemical analysis showed that the product has to be pure struvite (>99%), which was further identified by scanning electron microscope and X-ray diffraction to be quality struvite that might be used for agricultural purpose. Overall, low-cost magnesium ion collected from Rift Valley Lake can be a potentially candidate for sustainable phosphorus recovery from urine and any other phosphorus containing waste stream.
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Affiliation(s)
- Awoke Guadie
- Department of Biology, College of Natural Sciences, Arba Minch University, Arba Minch 21, Ethiopia; Key Laboratory of Environmental Biotechnology Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, PR China.
| | - Abaynesh Belay
- Department of Civil and Environmental Engineering, Norwegian University of Science and Technology, Trondheim, Norway
| | - Wenzong Liu
- Key Laboratory of Environmental Biotechnology Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, PR China
| | - Asamin Yesigat
- Department of Environmental Engineering, College of Biological and Chemical Engineering, Addis Ababa Science and Technology University, Addis Ababa, 16417, Ethiopia
| | - Xiaodi Hao
- Sino-Dutch R&D Centre for Future Wastewater Treatment Technologies/Key Laboratory of Urban Stormwater System and Water Environment, Beijing University of Civil Engineering and Architecture, Beijing, 100044, China
| | - Aijie Wang
- Key Laboratory of Environmental Biotechnology Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, PR China.
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De Paepe J, De Pryck L, Verliefde ARD, Rabaey K, Clauwaert P. Electrochemically Induced Precipitation Enables Fresh Urine Stabilization and Facilitates Source Separation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:3618-3627. [PMID: 32049503 DOI: 10.1021/acs.est.9b06804] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Source separation of urine can enable nutrient recycling, facilitate wastewater management, and conserve water. Without stabilization of the urine, urea is quickly hydrolyzed into ammonia and (bi)carbonate, causing nutrient loss, clogging of collection systems, ammonia volatilization, and odor nuisance. In this study, electrochemically induced precipitation and stabilization of fresh urine was successfully demonstrated. By recirculating the urine over the cathodic compartment of an electrochemical cell, the pH was increased due to the production of hydroxyl ions at the cathode. The pH increased to 11-12, decreasing calcium and magnesium concentrations by >80%, and minimizing scaling and clogging during downstream processing. At pH 11, urine could be stabilized for one week, while an increase to pH 12 allowed urine storage without urea hydrolysis for >18 months. By a smart selection of membranes [anion exchange membrane (AEM) with a cation exchange membrane (CEM) or a bipolar membrane (BPM)], no chemical input was required in the electrochemical cell and an acidic stream was produced that can be used to periodically rinse the electrochemical cell and toilet. On-site electrochemical treatment, close to the toilet, is a promising new concept to minimize clogging in collection systems by forcing controlled precipitation and to inhibit urea hydrolysis during storage until further treatment in more centralized nutrient recovery plants.
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Affiliation(s)
- Jolien De Paepe
- Center for Microbial Ecology and Technology (CMET), Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Gent, Belgium
- Department d'Enginyeria Química, Biològica i Ambiental, Universitat Autònoma de Barcelona, Bellaterra, 08193 Barcelona, Spain
- Center for Advanced Process Technology and Urban Resource Efficiency (CAPTURE), Ghent University, Coupure Links 653, 9000 Gent, Belgium
| | - Laurens De Pryck
- Center for Microbial Ecology and Technology (CMET), Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Gent, Belgium
| | - Arne R D Verliefde
- Center for Advanced Process Technology and Urban Resource Efficiency (CAPTURE), Ghent University, Coupure Links 653, 9000 Gent, Belgium
- Particle and Interfacial Technology Group (PaInt), Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Gent, Belgium
| | - Korneel Rabaey
- Center for Microbial Ecology and Technology (CMET), Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Gent, Belgium
- Center for Advanced Process Technology and Urban Resource Efficiency (CAPTURE), Ghent University, Coupure Links 653, 9000 Gent, Belgium
| | - Peter Clauwaert
- Center for Microbial Ecology and Technology (CMET), Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Gent, Belgium
- Center for Advanced Process Technology and Urban Resource Efficiency (CAPTURE), Ghent University, Coupure Links 653, 9000 Gent, Belgium
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25
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Guan T, Kuang Y, Li X, Fang J, Fang W, Wu D. The recovery of phosphorus from source-separated urine by repeatedly usable magnetic Fe 3O 4@ZrO 2 nanoparticles under acidic conditions. ENVIRONMENT INTERNATIONAL 2020; 134:105322. [PMID: 31739135 DOI: 10.1016/j.envint.2019.105322] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Revised: 09/07/2019] [Accepted: 11/11/2019] [Indexed: 06/10/2023]
Abstract
The separation of urine at source for phosphorus (P) recovery is attractive taking into account the high P concentration and small volume. However, the treatment of urine is still challenging due to its unpleasant odor and hygiene problems. Because the above problems could be solved by acidification to keep the pH of urine below 4, we propose a novel strategy to recover P from acidified urine using tailored hydrous zirconia-coated magnetite nanoparticles (Fe3O4@ZrO2). This strategy involves the selective adsorption of phosphate by easily separable and reusable Fe3O4@ZrO2, the desorption of adsorbed phosphate, and the precipitation of desorbed phosphate as calcium phosphate fertilizer. The results indicated that at pH 4, the P in synthetic urine was selectively adsorbed and could be exhausted using Fe3O4@ZrO2. Nearly all (>97.5%) of the sequestered P on the Fe3O4@ZrO2 nanoparticles was stripped using ≥1 M NaOH solution and ~100% of the stripped P was then successfully transformed into calcium phosphate, upon adding CaCl2 at pH >12 and a Ca/P molar ratio of 3. The liquid/solid (Fe3O4@ZrO2 particles) mixture could be conveniently separated for reuse using an external magnetic field. The reusability of the Fe3O4@ZrO2 nanoparticles in the extraction of P from synthetic urine was confirmed using five cycles of the adsorption-desorption process and their performance validated using real urine samples. The mechanism of phosphate adsorption was investigated using XPS, FTIR and zeta potential measurements, showing that phosphate was chemically adsorbed on the surface through direct coordination to zirconium atom via ligand exchange.
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Affiliation(s)
- Tong Guan
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, No. 800, Dongchuan Road, Shanghai 200240, China
| | - Yue Kuang
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, No. 800, Dongchuan Road, Shanghai 200240, China
| | - Xiaodi Li
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, No. 800, Dongchuan Road, Shanghai 200240, China
| | - Jing Fang
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, No. 800, Dongchuan Road, Shanghai 200240, China
| | - Wenkan Fang
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, No. 800, Dongchuan Road, Shanghai 200240, China
| | - Deyi Wu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, No. 800, Dongchuan Road, Shanghai 200240, China.
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26
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Christiaens MER, De Vrieze J, Clinckemaillie L, Ganigué R, Rabaey K. Anaerobic ureolysis of source-separated urine for NH 3 recovery enables direct removal of divalent ions at the toilet. WATER RESEARCH 2019; 148:97-105. [PMID: 30352325 DOI: 10.1016/j.watres.2018.10.021] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Revised: 10/01/2018] [Accepted: 10/07/2018] [Indexed: 06/08/2023]
Abstract
Source-separated urine is of interest for nutrient recovery. Most nitrogen recovery technologies rely on ammonia (NH3) as input, which requires ureolysis. As urease positive bacteria are widespread, source-separated urine is unstable, not only leading to NH3 release but also loss, odor nuisance, and downstream scaling. Hence, ureolysis ideally occurs in a closed controlled environment close to the toilet. We characterized microbial-induced ureolysis, subsequent divalent cation precipitation, and fermentation in anaerobic sequencing batch reactors (SBRs) at 15 °C and 28 °C. Temperatures were a proxy for urine hydrolysis in a wet well at street level or in the toilet, respectively. The need for inoculation and the metabolic stability was assessed by inoculation with autofermented urine or a mixture of anaerobic digestion and fermentation sludge. The highest specific ureolysis rates in the SBRs were achieved at 28 °C: 2107 ± 395 and 1948 ± 1121 mg N g VSS-1 d-1, for the mixed and autofermented inoculum, respectively. For Ca2+ and Mg2+ precipitation, and organics fermentation, autofermented urine at 28 °C performed best with 47.9 ± 16.4 mg Ca2+ g VSS-1 d-1, 8.2 ± 4.6 mg Mg2+ g VSS-1 d-1, and 623 ± 129 mg VFA-COD g VSS-1 d-1, respectively. This indicates the hydrolysis reactor should be close to the toilet. The selected inoculum did not impact ureolysis, whereas both Ca2+ and Mg2+ precipitation and fermentation were better in the SBRs with autofermented urine. Ureolysis was identified as the only process significantly impacting the microbial community, indicating external inoculation would not be required. A urine hydrolysis reactor in the toilet without external inoculation could thus serve as a controlled environment to release NH3 and remove divalent cations to prevent scaling in downstream transport and processing. For practical implementation in a household toilet, the reactor should be designed for user-friendly precipitate discharge and odor control.
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Affiliation(s)
- Marlies E R Christiaens
- Center for Microbial Ecology and Technology (CMET), Ghent University, Coupure Links 653, B-9000, Gent, Belgium
| | - Jo De Vrieze
- Center for Microbial Ecology and Technology (CMET), Ghent University, Coupure Links 653, B-9000, Gent, Belgium
| | - Lorenzo Clinckemaillie
- Center for Microbial Ecology and Technology (CMET), Ghent University, Coupure Links 653, B-9000, Gent, Belgium
| | - Ramon Ganigué
- Center for Microbial Ecology and Technology (CMET), Ghent University, Coupure Links 653, B-9000, Gent, Belgium
| | - Korneel Rabaey
- Center for Microbial Ecology and Technology (CMET), Ghent University, Coupure Links 653, B-9000, Gent, Belgium.
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27
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Senecal J, Nordin A, Simha P, Vinnerås B. Hygiene aspect of treating human urine by alkaline dehydration. WATER RESEARCH 2018; 144:474-481. [PMID: 30075443 DOI: 10.1016/j.watres.2018.07.030] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Revised: 06/29/2018] [Accepted: 07/11/2018] [Indexed: 06/08/2023]
Abstract
Over four billion people are discharging untreated human excreta into the environment without any prior treatment, causing eutrophication and spreading disease. The most nutrient rich fraction is the urine. Urine can be collected separately and dehydrated in an alkaline bed producing a nutrient rich fertiliser. However, faecal cross-contamination during the collection risks to introduce pathogens to the urine. The objective of this hygiene assessment was to study the inactivation of five microorganisms (Ascaris suum, Enterococcus faecalis, bacteriophages MS2 and ΦX 174 and Salmonella spp) in alkaline dehydrated urine. Fresh human urine was dehydrated in wood ash at 42 °C until the pH decreased to ≤10.5, at which point the saturated ash was inoculated with faeces containing the microorganisms and left open to the air (mimicking stockpiling of the end product) at temperatures of 20 and 42 °C. The bacteria and bacteriophages were inactivated to below the detection limit (100 cfu ml-1 for bacteria; 10 pfu mL-1 for bacteriophages) within four days storage at 20 °C. A. suum inactivation data was fitted to a non-linear regression model, which estimated a required 325 days of storage at 20 °C and 9.2 days at 42 °C to reach a 3 log10 reduction. However, the urine dehydration in itself achieved a concentration <1 A. suum per 4 g of dehydrated medium which fulfil the WHO guidelines for unrestricted use.
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Affiliation(s)
- Jenna Senecal
- Swedish University of Agricultural Sciences, Department of Energy and Technology, Box 7032, SE-750 07, Uppsala, Sweden.
| | - Annika Nordin
- Swedish University of Agricultural Sciences, Department of Energy and Technology, Box 7032, SE-750 07, Uppsala, Sweden
| | - Prithvi Simha
- Swedish University of Agricultural Sciences, Department of Energy and Technology, Box 7032, SE-750 07, Uppsala, Sweden
| | - Björn Vinnerås
- Swedish University of Agricultural Sciences, Department of Energy and Technology, Box 7032, SE-750 07, Uppsala, Sweden
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28
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Simha P, Senecal J, Nordin A, Lalander C, Vinnerås B. Alkaline dehydration of anion-exchanged human urine: Volume reduction, nutrient recovery and process optimisation. WATER RESEARCH 2018; 142:325-336. [PMID: 29890480 DOI: 10.1016/j.watres.2018.06.001] [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: 03/02/2018] [Revised: 05/25/2018] [Accepted: 06/02/2018] [Indexed: 06/08/2023]
Abstract
In urine-separating sanitation systems, bacterial urease enzymes can hydrolyse urea to ammonia during the pipe transport and storage of urine. The present study investigated whether it was possible to reduce the urine volume without losing the nitrogen as ammonia. A method for stabilising the urine prior to dehydration was developed. Briefly, fresh human urine was stabilised by passage through an anion-exchanger, added to an alkaline media (wood ash or alkalised biochar), and dehydrated. Urine dehydration was investigated at three temperatures: 40, 45 and 50 °C. The influence of various factors affecting the dehydration process was modelled and the rate of urine dehydration was optimised. Results indicated that 75% (v/v) of the urine has to pass through the ion-exchanger for alkaline stabilisation of urine to occur. At all investigated temperatures, the dehydrator accomplished >90% volume reduction of ion-exchanged urine, > 70% N retention and 100% recovery of P and K. To realise high degree of nutrient valorisation, this study proposes combining source-separation of human urine with alkaline dehydration.
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Affiliation(s)
- Prithvi Simha
- Department of Environmental Sciences and Policy, Central European University, Nádor utca 9, 1051 Budapest, Hungary; Swedish University of Agricultural Sciences, Department of Energy and Technology, Box 7032, SE-750 07 Uppsala, Sweden.
| | - Jenna Senecal
- Swedish University of Agricultural Sciences, Department of Energy and Technology, Box 7032, SE-750 07 Uppsala, Sweden
| | - Annika Nordin
- Swedish University of Agricultural Sciences, Department of Energy and Technology, Box 7032, SE-750 07 Uppsala, Sweden
| | - Cecilia Lalander
- Swedish University of Agricultural Sciences, Department of Energy and Technology, Box 7032, SE-750 07 Uppsala, Sweden
| | - Björn Vinnerås
- Swedish University of Agricultural Sciences, Department of Energy and Technology, Box 7032, SE-750 07 Uppsala, Sweden
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29
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Shi Y, Zhou L, Xu Y, Zhou H, Shi L. Life cycle cost and environmental assessment for resource-oriented toilet systems. JOURNAL OF CLEANER PRODUCTION 2018; 196:1188-1197. [PMID: 30245554 PMCID: PMC6106690 DOI: 10.1016/j.jclepro.2018.06.129] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Revised: 06/11/2018] [Accepted: 06/11/2018] [Indexed: 05/24/2023]
Abstract
The rich content of nutrients in human waste provides an outlook for turning it from pollutants to potential resources. The pilot-scale resource-oriented toilet with forward osmosis technology was demonstrated to have advantages to recover clean water, nitrogen, phosphorus, potassium, biogas, and heat from urine and feces. For the possibility of further full-scale implementation in different scenarios, six resource-oriented toilet systems and one conventional toilet system were designed in this study. The methodology of cost-benefit analysis and life cycle assessment were applied to analyze the life cycle economic feasibility and environmental sustainability of these systems. As results indicated, resource-oriented toilets with forward osmosis technology concentrating urine proved to have both economic and environmental benefit. The economic net present value results of new resource-oriented toilets were much better than conventional toilet. The energy consumption in resource-oriented toilets contributes a lot to the environmental impacts while resource recovery such as the fertilizer production and fresh water harvest in resource-oriented toilet systems offsets a lot. Taking both life cycle economic feasibility and environmental sustainability into consideration, the partial resource-oriented toilet (only recovering nutrients from urine) is the best choice, and the totally independent resource-oriented toilet could be applied to replace conventional toilets in areas without any external facilities such as sewer and water supply system etc.
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Key Words
- ADP elements, Abiotic Depletion Elements
- ADP fossil, Abiotic Depletion Fossil
- AP, Acidification Potential
- CNY, China Yuan
- CODCr, dichromate oxidizability
- Cost-benefit analysis
- DCB, 4,4′-diaminobiphenyl
- ED, electrodialysis
- ENPV, net economic present value
- EP, Eutrophication Potential
- FAETP, Freshwater Aquatic Ecotoxicity
- FO, forward osmosis
- Forward osmosis
- GWP, Global Warming Potential
- HTP, Human Toxicity Potential
- K, potassium
- LCA, life cycle assessment
- Life cycle assessment
- MAETP, Marine Aquatic Ecotoxity
- N, nitrogen
- NH3-N, ammonia nitrogen
- ODP, Ozone Layer Depletion Potential
- P, phosphorus
- POCP, Photochem. Ozone Creation Potential
- R11, trichlorofluoromethane
- RO, reverse osmosis
- Resource recovery
- SA, Scenario A
- SB1, Scenario B1
- SB2, Scenario B2
- SC1, Scenario C1
- SC2, Scenario C2
- SC3, Scenario C3
- SC4, Scenario C4
- STPs, sewage treatment plants
- Sb, antimony
- TDS, total dissolved solids
- TETP, Terrestric Ecotoxicity Potential (TETP)
- TN, total nitrogen
- TOrCs, trace organic compounds
- TP, total phosphorus
- Toilet
- USD, United States dollar
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Drangert JO, Tonderski K, McConville J. Extending the European Union Waste Hierarchy to Guide Nutrient-Effective Urban Sanitation toward Global Food Security—Opportunities for Phosphorus Recovery. FRONTIERS IN SUSTAINABLE FOOD SYSTEMS 2018. [DOI: 10.3389/fsufs.2018.00003] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
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