Simultaneous Chemical Oxygen Demand Research Articles

Ozonation for improved sludge reduction, cytotoxicity and estrogenicity control in anaerobic digestion

Anaerobic digestion (AD) is a common treatment for sludge reduction and stabilization. Simultaneously reductions in sludge chemical oxygen demand (COD), cytotoxicity, and estrogenicity are desired for safer handling and reuse. We investigated the impact, mechanism, and control strategy of ozonation (common sludge biodegradability method) on AD, methane production, and sludge cytotoxicity and estrogenicity modulations. Results revealed that ozone treatment could boost the methane production potential and rate by up to 36.5 and 69.2 %, respectively, but only after partial sludge digestion. Ozone modulated sludge cytotoxicity and estrogenicity, significantly improving this effect (maximum reductions of 28 and 23 %, respectively) by introducing anaerobically digested sludge to the ozonation module due to lowered volatile solids (VS) compared to raw sludge and less competition from the abundant biodegradable organics. Results support introducing ozone during AD for simultaneous COD reduction, and cytotoxicity and estrogenicity control.

Neuro-fuzzy modelling of a continuous stirred tank bioreactor with ceramic membrane technology for treating petroleum refinery effluent: a case study from Assam, India.

A continuous stirred tank bioreactor (CSTB) with cell recycling combined with ceramic membrane technology and inoculated with Rhodococcus opacus PD630 was employed to treat petroleum refinery wastewater for simultaneous chemical oxygen demand (COD) removal and lipid production from the retentate obtained during wastewater treatment. In the present study, the COD removal efficiency (CODRE) (%) and lipid concentration (g/L) were predicted using two artificial intelligence models, i.e., an artificial neural network (ANN) and a neuro-fuzzy neural network (NF-NN) with a network topology of 6-25-2 being the best for NF-NN. The results revealed the superiority of NF-NN over ANN in terms of determination coefficient (R2), root mean square error (RMSE), and mean absolute percentage error (MAPE). Three learning algorithms were tested with NF-NN; among them, the Bayesian regularization backpropagation (BR-BP) outperformed others. The sensitivity analysis revealed that, if solid retention time and biomass concentrations were maintained between 35 and 75h and 3.0g/L and 3.5g/L, respectively, high CODRE (93%) and lipid concentration (2.8g/L) could be obtained consistently.

REVIEW OF AEROBIC GRANULAR SLUDGE TECHNOLOGY AND APPLICATION IN WASTEWATER TREATMENT

This paper focuses on introducing an overview of aerobic granular sludge technology, granulation, removal efficiency and application of aerobic granules in wastewater treatment. Aerobic granular sludge has a bacterial layered structure including anaerobic, anoxic and aerobic bacteria in order from inside to outside layer, so it is capable of simultaneous chemical oxygen demand, nitrogen and phosphorus removal. Granular sludge also has capacity to remove persistent organic substances and adsorb heavy metals. As a result, aerobic granular sludge technology can be effectively applied for municipal and industrial wastewater treatment. Many wastewater treatment plants applying aerobic granular sludge technology have been deployed, most commonly in Europe and especially in the Netherlands, which is the first place to apply this technology in practical wastewater treatment with Nereda® trademark. However, aerobic granular sludge is stable on batch reactors and takes months to form stable granular sludge. Therefore, it is necessary to have further researches on the granulation mechanism and affective factors to shorten the time of aerobic granular sludge formation as well as maintain the long-term stability of the granular sludge and develop continuous reactors to maintain the stability of the aerobic granular sludge to meet the requirement of wastewater treatment plants in practice.

Performance of pilot-scale membrane aerated biofilm reactors integrated with anoxic nano-biotechnological reactor for domestic wastewater treatment

Membrane-aerated biofilm reactors (MABRs) have aroused increasing attention due to their excellent performance in treating wastewater, where the membranes behave as bio-carriers for microorganisms and bubbleless air diffusers. The MABR technology has not been fully commercialized due to reactor design and low total nitrogen (TN) removal efficiency at short hydraulic retention times (HRT). In this study, a hybrid system of MABR 1 integrated with an anoxic nano-biotechnological reactor filled with Granulated Nanoscale Oxyhydroxides of Fe (GNOF) media was evaluated to assess the improvement in nitrogen removal performance at 12, 10, and 4 h of HRTs. At the same time, another MABR (MABR 2) was operated individually at 12, 10, 8, 6, 4, and 2 h of HRTs to assess the influence of HRT on nitrogen removal performance. An enhancement in removal performance was reported in the hybrid MABR-GNOF, achieving the highest removal efficiencies of 74.3 ± 3.1% for ammonium nitrogen (NH4+-N), 69.8 ± 2.1% for total nitrogen (TN), and 90.9 ± 1.7% for chemical oxygen demand (COD), at 12 h HRT. The hybrid MABR-GNOF system attained 18% higher nitrogen removal than the MABR-only system at 12 h of HRT. A simultaneous anoxic nitrification-denitrification and COD oxidation might be developed for the removal of COD, NH4+-N, and TN from domestic wastewater by using GNOF as an electron acceptor in the hybrid MABR-GNOF unit. The findings in this study confirmed the possibility of integration of GNOF and MABR on a pilot scale and are promising for the application of this hybrid system on a full scale.

Micro-meso structure NaP zeolite @TiO2 nanocomposite: eco-friendly photocatalyst for simultaneous removal COD and degradation of methylene blue under solar irradiation.

A low-cost NaP zeolite@TiO2 nanocomposite catalyst with zeolite Si/Al ratio lower than three were synthesized for the first time under hydrothermal condition. The nanocomposites were characterized by different methods such as Fourier transform infrared (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), diffuse reflectance spectroscopy (DRS), N2 physisorption, NH3 temperature-programmed desorption (NH3-TPD), fluorescence microscopy, thermal analysis (TGA/DTA) and zeta potential analysis. The results showed that a micro-meso structure NaP zeolite with higher surface area and acidity with respect to pure zeolite was prepared. TiO2 nanoparticle was dispersed over the whole of zeolite without aggregation. A reduction of the TiO2 bandgap nanoparticle was observed from DRS spectra. The photocatalytic activity of low-cost NaP zeolite@TiO2 nanocomposite was tested for simultaneous methylene blue dye (MB) and chemical oxygen demand (COD) under solar and ultraviolet light. The result showed that the nanocomposite catalyst has great potential (above 90%) for COD removal discolouring of MB (about 99.6%) at room temperature. The optimum amount of some parameters such as the loaded amount of TiO2 (0.36g), catalyst dosage (0.1g), time (2h), initial dye concentration (100mg/L), solution pH value (about 7) under solar light were considered. In addition, present negative charge in the surface that show in zeta potential confirm the high activity of catalyst to interaction with cationic dye. As a further advantage, the NaP zeolite@TiO2 nanocomposite was easier to be separated in aqueous media than the pure TiO2 powders, making possible the reuse several times (over five runs) without using oxidant. Finally, the NaP zeolite@TiO2 nanocomposite was used for COD abatement in wastewater from two real industrial streams. The MB degradation kinetics were fitted by a pseudo-first-order model with K = 0.534h-1.

A dual photoelectrode-based double-chambered microbial fuel cell applied for simultaneous COD and Cr (VI) reduction in wastewater

Cerium oxide (CeO2) and cuprous oxide (Cu2O) were used for the first time as photoanode and photocathode, respectively, in a microbial fuel cell (MFC) for simultaneous reduction of chemical oxygen demand (COD) and Cr(VI) in wastewater. The photoelectrodes, viz. Photoanode and photocathode were separately prepared by impregnating activated carbon fiber (ACF) with the respective metal oxide nanoparticles, followed by growing carbon nanofibers (CNFs) on the ACF substrate using catalytic chemical vapor deposition. The MFC, operated under visible light irradiation, showed reduction in COD and Cr(VI) by approximately 94 and 97%, respectively. The MFC also generated high bioelectricity with a current density of ~6918 mA/m2 and a power density of ~1107 mW/m2. The enhanced performance of the MFC developed in this study was attributed to the combined effects of the metal oxide photocatalysts, the graphitic CNFs, and the microporous ACF substrate. The MFC based on the inexpensive transition metal oxides-based photoelectrodes developed in this study has a potential to be used at a large scale for treating the industrial aqueous effluents co-contaminated with organics and toxic Cr(VI).

The Evaluation of Simultaneous COD and Sulfate Removal at High COD/SO42− Ratio and Haloalkaline Condition

The effects of different electron donors on sulfate reduction at high COD/SO42− and haloalkaline conditions were investigated. For this purpose, the anaerobic submerged membrane reactor, fed with acetate and ethanol as an electron donor, was operated at a salinity of 10 g NaCl/L and a high pH (about 9.5) for 210 days. The bioreactor was inoculated with a mixed haloalkaliphilic culture and was enriched with saline soda from Lake Van, Turkey. The bioreactor’s performance was mainly evaluated with the removal of chemical oxygen demand (COD) and sulfate and changes in microbial community. A significant increase for both COD and sulfate removal was simultaneously achieved in the ethanol-fed bioreactor. The highest removal efficiency of COD and sulfate was about 70% and 80%, respectively, once the ratio of COD/SO42− was 6. The effect of hydraulic retention time on treatment performance of the bioreactor was inconsiderable as a result of the low flux during the whole operation time. There was no biogas production throughout the experiment due to the haloalkaline condition in reactor medium. From DGGE analysis, it was postulated that ethanol usage can cause bacterial abundance and diversity in bioreactor medium with no detection of sulfate-reducing bacteria.

Treatment of industrial effluents and assessment of their impact on the structure and function of microbial diversity in a unique Anoxic-Aerobic sequential batch reactor (AnASBR)

A novel Anoxic-Aerobic Process (AnAP) that eliminated the anaerobic process was optimized and operated for the simultaneous remediation of phosphate, nitrate, and chemical oxygen demand (COD) from industrial effluents. Two sequential batch reactors (SBR) with AnAP were established for the treatment of effluent from two industries; phosphate fertilizer (AnASBR_PPL) and dairy industry (AnASBR_DW). The adaptability of the bacterial consortium in the SBRs, dominated by denitrifying phosphate accumulating organisms (DNPAOs), facilitates the stable performance of AnAP for simultaneous nutrient and COD removal. Up to 90% and ~80% of COD removal were achieved in AnASBR_PPL and AnASBR_DW, respectively. Nearly complete denitrification was observed along with phosphate removal accounted for ~90% in both the reactors. Granulation of sludge has been widely reported in aerobic reactors; however, interestingly, in this study, partial granulation of the sludge was observed in both the AnASBRs which facilitated the microorganisms to uptake a minimal amount of phosphate and nitrate even under the aerobic condition. The underlying mechanism of DNPAOs and other associated microbes in the consortium were investigated for microbial diversity by 16S rDNA based targeted amplicon sequencing using the Illumina platform and imputed metagenomic analysis. The dominance of Betaproteobacteria, Alphaproteobacteria, Gammaproteobacteria, and Bacteroidia was observed in AnASBRs. At steady-state operation, the identity of the core community members remained largly stable, but their relative abundances changed considerably in both the reactors as a function of varying industrial effluent. However, population of few strains such as Lactobacteriales, Enterobacteriales changed drastically with respect to the influent, as these strains were predominat in AnASBR_DW but not present in AnASBR_PPL. The dominant strains were the vital contributor to the gene pool encoding for denitrification, dephosphatation, TCA cycle, glycolysis, EPS production, and polyhydroxyalkanoate (PHA) storage, etc. Few less abundant but persistent species were also detected as contributors to these functional groups. It unveiled the TCA cycle remains preferable over conventional glycolysis in both the SBR irrespective of carbon source. The new AnASBR was proved to be an efficient alternative system that is energy efficient with higher ease of operation for the treatment of different industrial effluents without fail.

Synergistic removal of cadmium and organic matter by a microalgae-endophyte symbiotic system (MESS): An approach to improve the application potential of plant-derived biosorbents

Plant-derived materials as environmentally friendly biosorbents to remove heavy metals from wastewater have been extensively studied. However, the chemical oxygen demand (COD) increase caused by the plant-derived biosorbent has not been considered previously. In this study, water hyacinth was used as biosorbent to remove Cd(II) from wastewater. About 66% of Cd(II) was removed by the biosorbent with a maximum biosorption capacity (qmax) of 21.6 mg g−1. However, the COD of the filtrate increased from 0 to 292 mg L−1 during this process. Subsequently, endophytes, microalgae and the microalgae-endophyte symbiotic system (MESS) were assessed for the simultaneous Cd(II) and COD removal. Among these three systems, the MESS achieved the best performance. After 3 d of inoculation, the extent of total Cd(II) removal increased to 99.2% while COD decreased to 77 mg L−1. This study provides a new insight into the application of a plant-derived biosorbent in combination with microalgae and endophytes for the effective treatment of heavy metal-bearing wastewater.

Simultaneous hydrogen generation and COD reduction in a photoanode-based microbial electrolysis cell

A phenolic precursor-based carbon film dispersed with cerium oxide (CeO2) and reduced graphene oxide (rGO) is prepared as the electrodes of a microbial electrolysis cell (MEC) for simultaneous hydrogen (H2) production and reduction of chemical oxygen demand (COD) in wastewater under visible light irradiation. The oxides are in situ dispersed in the polymerization reaction mixture during the synthesis stage of the phenolic film. The maximum Coulombic energy efficiency, overall H2 recovery and cathodic recovery of the CeO2-rGO/carbon film-based MEC are measured to be approximately 95, 93 and 98%, respectively at 1 V (Ag/AgCl), whereas COD reduction in the wastewater is measured to be approximately 95%. The improved hydrogen evolution and organic degradation are attributed to the electroconductive graphitic rGO and photocatalytic CeO2, respectively. The metal oxide-rGO-dispersed carbon nanocomposite film-based MEC provides an efficient means for simultaneously producing H2 and treating the organics-laden wastewater.

Hydrogen production from microbial fuel cells-ammonia electrolysis cell coupled system fed with landfill leachate using Mo2C/N-doped graphene nanocomposite as HER catalyst

In this work, we reported hydrogen production from ammonia-rich wastewater using series stacked microbial fuel cells (MFCs)-ammonia electrolytic cell (AEC) coupled system with Mo2C/N-doped graphene (Mo2C/N-rGO) nanocomposite as hydrogen evolution reaction (HER) catalyst. The electrocatalytic activity of Mo2C/N-rGO nanocomposite towards HER, the performance of simultaneous bioelectricity and hydrogen production as well as landfill leachate treatment of this coupled system were investigated under continuous parallel flow mode. Results demonstrated that four air-cathode MFCs in series stacking harvested the highest power density of 536 mW m−2 when fed with glucose and ammonium mixture, and meanwhile approximately 59 μL gMo2C/N-rGO−1 h−1 of hydrogen production rate was achieved with continuous bioelectricity supply to the AEC unit. As the substrate was shifted to actual landfill leachate (dilution ratio of 1:4), only ca. 143 mW m−2 of maximal output power was obtained from the series stacked MFCs, but it still accomplished 71% NH4+-N removal efficiency and about 42 μL gMo2C/N-rGO−1 h−1 of hydrogen production rate. This MFCs-AEC coupled bio-electrochemical system highlighted its potential for hydrogen production from real landfill leachate along with simultaneous chemical oxygen demand and ammonia-nitrogen removal without the need for external electricity supply, thus achieving the resource and energy re-utilization of ammonia-rich wastewater.

Simultaneous chemical oxygen demand removal, methane production and heavy metal precipitation in the biological treatment of landfill leachate using acid mine drainage as sulfate resource

Biological treatment played an important role in the treatment of landfill leachate. In the current study, acid mine drainage (AMD) was used as a source of sulfate to strengthen the anaerobic treatment of landfill leachate. Effects of chemical oxygen demand (COD) and SO42- mass concentration ratio on the decomposition of organic matter, methane production and sulfate reduction were investigated and the microbial community was analyzed using the high throughout methods. Results showed that high removal efficiency of COD, methane production and heavy metal removal was achieved when the initial COD/SO42- ratio (based on mass) was set at 3.0. The relative abundance of anaerobic hydrogen-producing bacteria (Candidatus Cloacamonas) in the experimental group with the addition of AMD was significantly increased compared to the control. Abundance of hydrogenotrophic methanogens of Methanosarcina and Methanomassiliicoccus was increased. Results confirmed that AMD could be used as sulfate resource to strengthen the biological treatment of landfill leachate.

Granulation of Non-filamentous Bulking Sludge Directed by pH, ORP and DO in an Anaerobic/Aerobic/Anoxic SBR.

In an anaerobic/aerobic/anoxic (A/O/A) sequencing batch reactor (SBR), non-filamentous bulking sludge granulated after the adjustment of cycle duration and influent composition directed by pH, oxidation-reduction potential (ORP) and dissolved oxygen (DO). The turning points and plateaux of pH, ORP and DO profiles indicated the end of biochemical reactions, such as chemical oxygen demand (COD) consumption, P release, ammonium oxidation, P uptake and denitrification. The difference of nutrient concentration between the beginning and turning points represented the actual treatment capability of the sludge. Non-filamentous bulking with SVI30 of 255 mL g(-1) resulted in a huge biomass loss. After regulation, the cycle duration was shortened from 310 to 195 min without unnecessary energy input. In addition, the settling ability was obviously improved as SVI30 reduced to 28 mL g(-1). Moreover, matured granules with an average diameter of 600 μm were obtained after 45 days, and simultaneous COD, ammonium and phosphate (P) removal was also realized after granulation.

Simultaneous effective carbon and nitrogen removals and phosphorus recovery in an intermittently aerated membrane bioreactor integrated system.

Recovering nutrients, especially phosphate resource, from wastewater have attracted increasing interest recently. Herein, an intermittently aerated membrane bioreactor (MBR) with a mesh filter was developed for simultaneous chemical oxygen demand (COD), total nitrogen (TN) and phosphorous removal, followed by phosphorus recovery from the phosphorus-rich sludge. This integrated system showed enhanced performances in nitrification and denitrification and phosphorous removal without excess sludge discharged. The removal of COD, TN and total phosphorus (TP) in a modified MBR were averaged at 94.4 ± 2.5%, 94.2 ± 5.7% and 53.3 ± 29.7%, respectively. The removed TP was stored in biomass, and 68.7% of the stored phosphorous in the sludge could be recovered as concentrated phosphate solution with a concentration of phosphate above 350 mg/L. The sludge after phosphorus release could be returned back to the MBR for phosphorus uptake, and 83.8% of its capacity could be recovered.

Effect of Nitrogen Concentration on the Performance of Single-Chamber Microbial Fuel Cells

The nitrogen removal in wastewater using single chamber microbial fuel cells is an interesting process. The nitrogen removal from nitrogen wastewater was examined using single chamber air cathode microbial fuel cells (SC-MFCs). SC-MFCs were fed with synthetic wastewater containing the initial chemical oxygen demand (COD) 1,000mg L-1 and nitrogen (N) 125, 250, 625, and 875 mg-N L-1, respectively and operated under mesophilic batch mode. Performance of SC-MFCs with external resistances 1,000Ω was based on maximum power density, COD and nitrogen removal. The SC-MFCs with ammonia-N concentration 625 mg-N L-1 gained higher maximum power density by 160 mW m-2.The ammonium removal was 58%. The results suggested that SC-MFCs are potential technology for simultaneous nitrogen and COD removal; and electricity generation.

Impacts of variable pH on stability and nutrient removal efficiency of aerobic granular sludge.

The impact of pH variation on aerobic granular sludge stability and performance was investigated. A 9-day alkaline (pH=9) and acidic (pH=6) pH shocks were imposed on mature granules with simultaneous chemical oxygen demand (COD), nitrogen and phosphorus removal. The imposed alkaline pH shock (pH 9) reduced nitrogen and phosphorus removal efficiency from 88% and 98% to 66% and 50%, respectively, with no further recovery. However, acidic pH shock (pH 6) did not have a major impact on nutrient removal and the removal efficiencies recovered to their initial values after 3 days of operation under the new pH condition. Operating the reactors under alkaline pH induced granules breakage and resulted in an increased solids concentration in the effluent and a significant decrease in the size of the bio-particles, while acidic pH did not have significant impacts on granules stability. Changes in chemical structure and composition of extracellular polymeric substances (EPS) matrix were suggested as the main factors inducing granules instability under high pH.

Improving oxygen dissolution and distribution in a bioreactor with enhanced simultaneous COD and nitrogen removal by simply introducing micro-pressure and swirl.

Increasingly, environmental regulations are demanding more exacting chemical oxygen demand (COD) and nitrogen removal from wastewater, which come at a high economic cost. A very simple novel bioreactor, the micro-pressure swirl reactor (MPSR), can improve the dissolution and distribution of oxygen by the introduced micro-pressure swirl. Comparison with a conventional sequencing batch reactor (SBR) over 76 days of operation showed that this method can enhance simultaneous COD and nitrogen removal. By installing an aeration diffuser on one side of the two-dimensional MPSR, a swirl formed in the bioreactor that extended the retention time of the air bubbles. This unique flow regime, combined with the micro-pressure caused by the elevated water surface at the bubble outflow point, resulted in a higher level of dissolved oxygen (DO) in the MPSR. Aerobic and anaerobic zones that created appropriate conditions for simultaneous COD and nitrogen removal also formed in the MPSR. As the organic loading rate increased from 0.29 to 1.68 g COD/(L · day) over the test period, the COD removal efficiencies of the MPSR were generally 10-20 % greater than those of the SBR. In particular, the total nitrogen (TN) removal efficiencies of the MPSR and SBR were 40-50 and 20-35 %, respectively, whereas the TN concentrations in the MPSR effluent were always around 10 mg/L lower than those of the SBR. Further, because of the unique DO distribution, the bacterial species in the MPSR were more diverse and contributed to enhanced TN removal.

Influence of carbon source on nutrient removal performance and physical–chemical characteristics of aerobic granular sludge

The impact of carbon source variation on the physical and chemical characteristics of aerobic granular sludge and its biological nutrient (nitrogen and phosphorus) removal performance was investigated. Two identical sequencing batch reactors, R1 and R2, were set up. Granular biomass was cultivated to maturity using acetate-based synthetic wastewater. After mature granules in both reactors with simultaneous chemical oxygen demand (COD), ammonium and phosphorus removal capability were achieved, the feed of R2 was changed to municipal wastewater and R1 was continued on synthetic feed as control. Biological phosphorus removal was completely inhibited in R2 due to lack of readily biodegradable COD; however, the biomass maintained high ammonium and COD removal efficiencies. The disintegration of the granules in R2 occurred during the first two weeks after the change of feed, but it did not have significant impacts on settling properties of the sludge. Re-granulation of the biomass in R2 was then observed within 30 d after granules’ disintegration when the biomass acclimated to the new substrate. The granular biomass in R1 and R2 maintained a Sludge Volume Index close to 60 and 47 mL g−1, respectively, during the experimental period. It was concluded that changing the carbon source from readily biodegradable acetate to the more complex ones present in municipal wastewater did not have significant impacts on aerobic granular sludge characteristics; it particularly did not affect its settling properties. However, sufficient readily biodegradable carbon would have to be provided to maintain simultaneous biological nitrate and phosphorus removal.

The combined effects of COD/N ratio and nitrate recycling ratio on nitrogen and phosphorus removal in anaerobic/anoxic/aerobic (A2/O)-biological aerated filter (BAF) systems

The combined effects of chemical oxygen demand (COD) to total nitrogen ratio (COD/N) and nitrate recycling ratio (R) on simultaneous nitrogen, phosphorus, and COD removal were studied in a laboratory-scaled anaerobic/anoxic/aerobic (A2/O)-biological aerated filter (BAF) system. Variation in the COD/N ratio alone had no noticeable effect on COD removal and nitrification, with the effluent COD concentration of 37mg/L and ammonium concentration below the detection level. However, low COD/N ratio (3.0) with high R (200–600%) deteriorated the total nitrogen (TN) removal due to insufficient carbon source and oxygen presence (dissolved oxygen concentration: 0.31–0.72mg/L) in the anoxic zones of A2/O. At the COD/N ratio of 4.0, the TN removal efficiency steadily increased from 66% to 81% when R was increased from 100% to 400%, but decreased to 70% at the highest R (600%). At the high COD/N ratio of 5.5, the TN removal efficiency increased from 68% to 90% with R increasing from 100 to 600%. The phosphorus release amounts in the anaerobic zone of the A2/O increased from 16.2mg/L to 55mg/L with the COD/N ratio increasing from 3.0 to 5.5. Low COD/N ratios (3.0 and 4.0) had little effect on phosphorus removal, while high COD/N ratio (5.5) caused the phosphorus release in sedimentation tanks due to the residual carbon in effluent.

Energy efficient reconcentration of diluted human urine using ion exchange membranes in bioelectrochemical systems

Nutrients can be recovered from source separated human urine; however, nutrient reconcentration (i.e., volume reduction of collected urine) requires energy-intensive treatment processes, making it practically difficult to utilize human urine. In this study, energy-efficient nutrient reconcentration was demonstrated using ion exchange membranes (IEMs) in a microbial electrolysis cell (MEC) where substrate oxidation at the MEC anode provides energy for the separation of nutrient ions (e.g., NH4+, HPO42−). The rate of nutrient separation was magnified with increasing number of IEM pairs and electric voltage application (Eap). Ammonia and phosphate were reconcentrated from diluted human urine by a factor of up to 4.5 and 3.0, respectively (Eap = 1.2 V; 3-IEM pairs). The concentrating factor increased with increasing degrees of volume reduction, but it remained stationary when the volume ratio between the diluate (urine solution that is diluted in the IEM stack) and concentrate (urine solution that is reconcentrated) was 6 or greater. The energy requirement normalized by the mass of nutrient reconcentrated was 6.48 MJ/kg-N (1.80 kWh/kg-N) and 117.6 MJ/kg-P (32.7 kWh/kg-P). In addition to nutrient separation, the examined MEC reactor with three IEM pairs showed 54% removal of COD (chemical oxygen demand) in 47-hr batch operation. The high sulfate concentration in human urine resulted in substantial growth of both of acetate-oxidizing and H2-oxidizing sulfate reducing bacteria, greatly diminishing the energy recovery and Coulombic efficiency. However, the high microbial activity of sulfate reducing bacteria hardly affected the rate of nutrient reconcentration. With the capability to reconcentrate nutrients at a minimal energy consumption and simultaneous COD removal, the examined bioelectrochemical treatment method with an IEM application has a potential for practical nutrient recovery and sustainable treatment of source-separated human urine.