Moving Bed Biofilm Reactor Research Articles

Moving-bed biofilm reactor for saline wastewater treatment: Different types of carriers, versatile nitrifying reactions, and functional microbial groups

The biofilm carriers are of significance for the operation of the moving bed biofilm reactor (MBBR) system. However, knowledge about the nitrification process with different types of carriers is still limited, particularly for saline wastewater treatment. In this study, six different carriers were applied to assess their ability for nitrification in the MBBRs through a long-term continuous operation with the hydraulic retention time reduced from 21.6 h to 3.1 h. Ammonia removal could be effectively achieved with a loading rate up to 14 g NH4+-N/d in all carriers (>91 %), except for carriers 3 (84 %) and 4 (78 %). Moreover, partial nitrification was established and maintained in the MBBR with carrier 4, while full nitrification occurred in others. The microbial structure revealed that, ammonia-oxidizing bacteria, nitrite-oxidizing bacteria, and denitrifiers were dominant with the overall relative abundance of 38.82 %, 51.30 %, 26.90 %, 59.84 %, 49.54 %, and 51.92 % in each MBBR, suggesting the possibility of achieving simultaneous nitrification and denitrification. The findings of this study have shed lights into the nitrogen conversion in MBBRs with different carriers for saline wastewater treatment.

Peroxymonosulfate activation by suspended biogenic manganese oxides for polishing micropollutants in wastewater effluent

The activation of peroxymonosulfate (PMS) to generate radical oxygen species (ROS) for in situ chemical oxidation has been shown to be an efficient technology for polishing micropollutants in wastewater effluent. Thus, it is also of great importance to develop environmental-friendly catalysts for PMS activation. The present study employed suspended biogenic manganese oxides (BioMnOx) to activate PMS for the efficient micropollutant removal. In a feasibility test, relatively high removal efficiencies (>80 %) of 14 selected micropollutants were obtained over short reaction times (20 min), in particular for refractory micropollutants such as carbamazepine (98 %), diclofenac (100 %) and metoprolol (81 %). The inhibition effect of coexisting anions to PMS activation was also investigated, which showed that the addition of HCO3– inhibited this process, while the addition of Cl– showed negligible effect. Based on radical quenching experiments, sulfate radical, hydrogen radical and singlet oxygen were all involved in the PMS activation process, while the responsible ROS for micropollutants removal were compound-specific. Furthermore, a novel BioMnOx/PMS system was established by utilising BioMnOx-coated carriers as catalyst, which were obtained from a previously engineered moving bed biofilm reactor (MBBR). This special BioMnOx/PMS system was then applied as an effluent polishing step. Results showed that most micropollutants were efficiently removed through the BioMnOx/PMS system, such as diclofenac (91 %) and sulfamethoxazole (98 %). Lastly, the toxicity of the MBBR effluent was determined by Vibrio fisheri, which showed minimum toxic effect after the polishing treatment.

Photo-Fenton like process as polishing step of biologically co-treated olive mill wastewater for phenols removal

In this study, UVC or sunlight assisted photo-Fenton like process (PFI) using iron(III) iminodisuccinate (Fe-IDS) as catalyst was investigated for the first time as post-treatment method of a Moving Bed Biofilm Reactor (MBBR) for the treatment of olive mill wastewater (OMW). Hydraulic retention time for the MBBR process was 24 h, while the treatment time for the PFI process was 3 h under UVC or solar light irradiation. Before the MBBR treatment, OMW was centrifuged and mixed with synthetic urban wastewater to simulate conditions in a real wastewater treatment plant (WWTP). The MBBR was highly effective in reducing Biological Oxygen Demand (BOD5) and Chemical Oxygen Demand (COD) (97 and 91%, respectively), but less effective (57%) in the removal of total phenols (TPHs). PFI was optimized for TPHs removal through response surface methodology. UVC driven PFI allowed to reach higher TPHs removal than sunlight driven PFI. Fe (III) dosage was set at 2 mg/L while optimum H2O2 dosage resulted to be 144 mg/L. In these conditions, the UVC driven process allowed to obtain a TPHs removal of 99%, reaching a final TPHs concentration of 0.07 ± 0.01 mg/L.

Salt-tolerant heterotrophic nitrification and aerobic denitrification (HNAD) bacterium enhancing a pilot-scale moving bed biofilm reactor (MBBR) treating mariculture wastewater treatment with different COD/TN ratios

Efficient nitrogen (N) removal from mariculture wastewater is one of the important measures to protect the marine ecological environment. A moving bed biofilm reactor (MBBR) inoculating heterotrophic nitrification and aerobic denitrification (HNAD) bacteria was set and the effects of chemical oxygen demand (COD) and total nitrogen (TN) (COD/TN) ratios on N removal performance, enzymatic activity, biofilm characteristics and microbial community were discussed. Results showed that a more stable N removal performance was obtained in the MBBR process inoculating HNAD bacteria under low COD/TN ratio compared with the conventional MBBR. The removal efficiency of nitrate nitrogen (NO3−-N) declined with COD/TN ratio decrease, and protein (PN) and polysaccharide (PS) concentration decreased from 284.3 and 37.1 mg (g VSS)−1 to 42.9 and 14.4 mg (g VSS)−1 with low ammonia monooxygenase (AMO), nitrite reductase (NIR) and nitrate reductase (NR) activities. Sequencing analysis revealed that strain Zobellella B307 became the dominant microorganism (the relatively abundance is 2.33–5.60 %), and its relatively abundance and the functional genes related to N metabolism reduced from 15.38 % to 9.66 % and 0.61 % to 0.55 % with COD/TN ratio decrease to explain the reason for the decrease of N removal efficiency. This study can provide a deep insight into N removal mechanism of the reactor inoculating HNAD bacteria under different COD/TN ratios.

Effects of media length on biofilms and nitrification in moving bed biofilm reactors

Biofilms grown on free-floating plastic media are increasingly being used to cultivate biofilms in integrated fixed film activated sludge (IFAS) and moving bed bioreactor (MBBR) systems for wastewater treatment with the common goal of increasing nitrogen removal. Fundamental principles of fluid dynamics dictate that the length of internal media channels affects fluid velocities and shear forces across biofilm surfaces, which in turn should affect rates of mass transfer and biofilm growth and activity, but little is known about media length effects on water quality and biofilm characteristics. It was hypothesized that length affects biofilm thickness, microbial populations and their activities, and system performance. Nitrification rates and biofilm characteristics were monitored in parallel continuous flow, bench-scale MBBRs systems with media length as a controlled variable. Longer media produced biofilms with approximately twice the thickness and twice the mass per unit area than did media with one-third their length. Based on calculated head losses, the combined effects of length and constriction of internal channels led to an estimated 77% reduction in fluid velocity through the longer media relative to the shorter media. Longer media demonstrated more rapid development of nitrite oxidizing bacteria (NOB) activity than the shorter media over much of the study, as indicated by measurements of nitrite and nitrate, but AOB activity was similar in the two media. Both biomass and NOB activity were concentrated toward media ends, while ammonia oxidizing bacteria (AOB) activity was uniformly distributed across the media, based on testing of sectioned media. 16s rRNA amplicon sequencing indicated the presence of several putative heterotrophic nitrifying families, particularly Xanthomonadaceae, Comamonadadeae and Microbacteriaceae, as well as the autotrophic Bradyrhizobiacea (which includes the NOB Nitrobacter) were common on both media throughout the study. The short media enriched for Nitrosomonadaceae, which includes the AOB genus Nitrosomonas, while minimal autotrophic AOBs were found in the long media biofilm. These results provide insights to the design of media for improved performance, particularly with respect to nitrite versus nitrate production, which may be useful to improve nitrification and for energy saving processes for nitrogen removal such as deammonification. The research also provides fundamental insights regarding the effects of media geometry on biofilm structure and function, which advances our understanding of environmental factors affecting biofilm development.

Quantification of some ARVs' removal efficiency from wastewater using a moving bed biofilm reactor.

To date, in South Africa alone, there are an estimated 4.5 million people receiving antiretroviral (ARV) therapy. This places South Africa as the country with the largest ARV therapy programme in the world. As a result, there are an increasing number of reports on the occurrence of ARVs in South African waters. Achieving efficient and bio-friendly methods for the removal of these pollutants is considered as a concern for environmental researchers. This study aims at studying the efficiency of a moving bed biofilm reactor (MBBR) system for removing ARVs from wastewater. A continuous-flow laboratory scale system was designed, built, installed, and operated at a carrier filling rate of 30%, an organic loading rate of 0.6 kg COD/m3.d-1 OLR, a hydraulic retention time of 18h, and a 27.8 mL/min flow rate. The systems were monitored over time for the elimination of conventional wastewater parameters i.e., Biological Oxygen Demand, Chemical Oxygen Demand, and nutrients. The results showed that the MBBR system as a bio-friendly method has high efficiency in removing Nevirapine, Tenofovir, Efavirenz, Ritonavir and Emtricitabine from the synthetic influent sample with an average removal of 62%, 74%, 94%, 94% and 95%, respectively, after 10 days of operation.

Treatment of high-strength saline bilge wastewater by four pilot-scale aerobic moving bed biofilm reactors and comparison of the microbial communities

ABSTRACT Four Pilot-scale Moving Bed Biofilm Reactors (MBBRs) were operated for the treatment of real, saline, bilge wastewater. The MBBRs were connected in pairs to create two system configurations with different filling ratios (20%, 40%) and were operated in parallel. The inflow organic loading rate (OLR) varied from 3.6 ± 0.2 to 7.8 ± 0.6 g COD L−1 d−1, salinity was >15 ppt and three hydraulic residence times (HRTs) were tested 48, 30 and 24 h. In both systems, the first-stage bioreactors (R1 and R3) eliminated the higher part of the organic load (57%–65%). The second-stage bioreactors (R2 and R4) removed an additional fraction (18%–31%) of the organic load received by the effluent of R1 and R3, respectively. The microbial communities of the influent wastewater, suspended, and attached biomass were determined using 16S rRNA gene amplicon sequencing analysis. The evolution of the microbial communities was investigated and compared over the different operational phases. The microbial communities of the biofilm presented higher diversity and greater stability in composition over time, while the suspended biomass exhibited intense and rapid changes in the dominance of genera. Proteobacteria, Bacteroidetes and Firmicutes were highly present in the biofilm. The genera Celeribacter, Novispirillum, Roseovarius (class: Alphaproteobacteria) and Formosa (class: Flavobacteriia) were highly present during all operational phases. Principal Component Analysis (PCA) was used to identify similarities between samples, exhibiting high relation of samples according to the series of the bioreactor (1st, 2nd).

Nitrogen migration law and recycling strategy in an innovative recirculating aquaculture system: Enhancing performance through electrocoagulation

In this study, electrocoagulation (EC), a green and efficient water treatment technology, was used to improve the performance of the Litopenaeus vannamei (L. vannamei) RAS. The main objective was to investigate the nitrogen migration law of the innovative L. vannamei RAS, establish a nitrogen recovery strategy, and promote the sustainable development of the L. vannamei RAS. It was found that 34.22 % of input nitrogen (NInput) accumulated in live shrimp, 3.83 % and 0.69 % of NInput existed in shed shrimp shell and dead shrimp, 41.31 % of NInput was removed by the water treatment equipment, 9.75 % of NInput was removed through water exchange, and 2.89 % of NInput accumulated in the RAS. Under the action of the EC, the removal of nitrogen by a microscreen drum filter (MDF), moving-bed biofilm reactor (MBBR) and foam separator (FS) increased by 26.39 %, 9.52 %, and 9.10 %, respectively. Moreover, a Chlorella vulgaris culture system was used to recycle the waste nitrogen of the L. vannamei RAS, with a nitrogen recovery rate of 80.84 %. These findings indicate that EC can significantly enhance the nitrogen removal of RAS, and the Chlorella vulgaris can be used for the efficient recovery of the waste nitrogen from RAS.

Long-Term Performance of Nitrogen Removal and Microbial Analysis in an Anammox MBBR Reactor with Internal Circulation to Provide Low Concentration DO.

The anammox process is considered as a revolutionary new denitrification technology. In this study, the anammox process was started in a single-stage moving bed biofilm reactor (MBBR) and the mechanism of excess removal of ammonia nitrogen was studied. At stage I (day 0-51), anammox bacteria (AnAOB) was enriched by feeding synthetic sewage without adding organic carbon. The removal rate of ammonia nitrogen was maintained at about 54% and the removal rate of total inorganic nitrogen was maintained at about 62%. At stage II (day 52-91), internal circulation was added into the MBBR. After adding internal circulation, the ammonium removal efficiency reached about 96% (at day 56) and the total nitrogen removal efficiency reached about 86%. At day 90, the biofilm sample was drowned out for high-throughput sequencing. The results showed that the relative abundance of AnAOB was 23.23%. The dominant anammox genus was Candidatus Brocadia. The relative abundance of Nitrosomonas (ammonia oxidizing bacteria, AOB) was 0.63%. The excess ammonia nitrogen was removed by AOB and AnAOB through the partial nitrification and anammox (PNA) process.

Assessing quinoline removal performances of an aerobic continuous moving bed biofilm reactor (MBBR) bioaugmented with Pseudomonas citronellolis LV1

This study evaluated the bioaugmentation potential of a quinoline-degrading strain Pseudomonas citronellolis LV1 inoculation into activated sludge for treating quinoline wastewater, and results indicated the inoculation of LV1 in aerobic continuous MBBR could substantially improve the quinoline removal performance with an improved removal efficiency of 34% averagely when quinoline was used as the sole carbon and nitrogen source. Additionally, efficient removal of quinoline in enhanced MBBR occurred at the influent pH of 7.0–8.0, hydraulic retention time (HRT) of 24–28 h and influent quinoline concentration of 100–700 mg·L−1. High-throughput sequencing analysis indicated that bioaugmentation could increase microbial diversity and shape the microbial community structure. Although the inoculant LV1 did not remain its dominance in stage III, bioaugmentation indeed induced the formation of effective microbial community, and the indigenous microbes including Flavobacterium, Pseudoxanthomonas, Pseudomonas, Vermamoeba, Dyadobacter and Sphingomonas might play the key role in quinoline removal. According to the PICRUSt, the enhanced genes encoding aromatic ring-cleavage enzyme, especially for N-heterocyclic ring-cleavage enzymes, could lead to the improved removal performance of quinoline in bioaugmentation stage. Moreover, the enhanced MBBR treated well actual coking wastewater, as indicated by high removal performance of quinoline, phenol and COD.

Bioaugmentation performance for moving bed biofilm reactor (MBBR) treating mariculture wastewater by an isolated novel halophilic heterotrophic nitrification aerobic denitrification (HNAD) strain (Zobellella B307)

Moving bed biofilm reactor (MBBR) demonstrates weak nitrogen removal for mariculture wastewater treatment under high salinity environment. An isolated novel halophilic heterotrophic nitrification aerobic denitrification (HNAD) strain (Zobellella B307) was applied in MBBR process to enhance nitrogen removal. Results showed that strain Zobellella B307 could remove 90.9% ammonia nitrogen (NH4+-N) and 97.1% nitrate nitrogen (NO3−-N) after 10 h cultivation, and strong resistance to salinity variation (high growth and nitrogen removal efficiency with salinity of 65‰) was observed. Besides, the chemical oxygen demand (COD), NH4+-N and NO3−-N removal reached 95.6%, 94.4% and 85.7% with the strain added into MBBR process. In addition, microbial community structure analysis reflected that the strain Zobellella B307 successfully proliferated (the relative abundance increased to 2.33%). The HNAD bacteria abundance increased and dominated during the nitrogen removal process with the strain inoculation. A microbial functional analysis revealed that the main dominant functional categories (carbohydrate metabolism and amino acid metabolism) increased with the bioaugmentation of strain Zobellella B307, thus improving the nitrogen removal.

Effect of dissolved oxygen on high C/N wastewater treatment in moving bed biofilm reactors based on heterotrophic nitrification and aerobic denitrification: Nitrogen removal performance and potential mechanisms

In this study, it was investigated the nitrogen removal (NR) performance and potential mechanism for high C/N wastewater treatment under different dissolved oxygen (DO) concentrations. The results showed that DO concentration significantly affected the removal efficiency of total nitrogen (TN). When the initial DO increased from 0.5 to 1.5 mg/L, TN removal efficiency significantly increased from 65 % to 85 %. However, a further DO increase did not promote TN removal, and the NR was only 80 % with an initial DO concentration of 3.5 mg/L. The effect of DO concentration on NR was influenced by the combined action of functional bacteria and electron flow. Excessive DO concentration did not positively affect NR efficiency but promoted electron utilization and respiratory proliferation. When the DO concentration was 1.5 mg/L, more electrons generated by sodium acetate metabolism were transferred to the aerobic denitrification process, compared to when the DO concentration was 3.5 mg/L.

Influence of physicochemical and hydrodynamic growth conditions on biofilm adhesion in a moving bed biofilm reactor

Influence of physicochemical and hydrodynamic growth conditions on biofilm adhesion in a moving bed biofilm reactor

Adding monochloramine to control the growth of nitrite oxidizers and complete ammonia oxidizers in nitrifying moving-bed biofilm reactor

This study investigated a new method of using monochloramine (NH2Cl) to enhance nitrite accumulation in nitrifying moving-bed biofilm bioreactor (MBBR). Firstly, two parallel MBBRs were operated - with 1 mg Cl2 L−1 of NH2Cl in MBBR-1 and without NH2Cl addition in MBBR-2. Both MBBRs oxidized ammonia completely. The NO2− accumulation efficiency increased by twofold in MBBR-1 but remained low in MBBR-2. Subsequently, the carriers from MBBR-1 and 2 were seeded into four sequencing batch reactors (SBRs) for in-situ nitrogen transformation analysis. The results showed that continuous exposure to 1 mg Cl2 L−1 of NH2Cl successfully accumulated 50 mg N L−1 of nitrite in the effluent and suppressed the growth of nitrite-oxidizing bacteria (NOB) and complete ammonia oxidizers (comammox). The finding indicated that adding NH2Cl could be a promising strategy to attain reliable nitrite accumulation for developing two-stage partial nitrification and anaerobic ammonia oxidation process in the future.

Morphological image analysis of biofilm evolution with quantitative analysis in a moving bed biofilm reactor

The quantitative analysis of biomass is essential for the research and application of moving bed biofilm reactors (MBBRs). However, the difficulty in measuring the attached growing biomass hinders the quantitative analysis of biofilm processes. In this study, a pilot-scale MBBR system was established to investigate biofilm evolution. The quantity of active heterotrophic and autotrophic biomass was measured throughout the entire culturing process. The total active biomass reached 250 mg COD/m2 when the biofilm attachment and detachment were balanced, and the corresponding autotrophic biomass contributes to as high as 17 % of the total biomass. Furthermore, quantitative image analysis was performed to obtain the thickness and morphological data of the biofilm evolution. Multivariate regression models were constructed based on the morphological data, which provided satisfactory prediction accuracy for the biofilm thickness and maturation. The most suitable carrier spots for biomass quantification and biofilm maturation were suggested. This work provided the life-cycle information of biofilm quantity and morphology of the MBBR, which contributes to the quantitative understanding of biofilm evolution at MBBRs.

Biologically recovered polyhydroxyalkanoates (PHA) as novel biofilm carrier for Acid Orange 7 decolourization: Statistical optimization of physicochemical and biological factors

The incorporation of biofilm process in activated sludge process is beneficial in enhancing treatment performance. In this study, biologically recovered polyhydroxyalkanoates (PHA) were explored as an eco-friendly alternative to conventional materials as the biofilm carrier. The PHA was shaped in a pellet form, melt-fused and added as a biofilm carrier in a moving bed biofilm reactor (MBBR). From the scanning electron microscopy image, biofilm was successfully developed on the PHA pellets, with a biofilm thickness of 236 μm. Modeling and optimization were conducted using response surface methodology (RSM) in predicting the AO7 decolourization efficiency and first-order kinetics in the integrated biofilm and suspended activated sludge processes. The interaction effects of three factors of suspended activated sludge concentration (2000–6000 mg/L), PHA pellet packing volume (1–20 %) and initial AO7 concentration (1–20 mg/L) on AO7 decolourization were studied. The AO7 decolourization efficiency and kinetics were well described using the respective reduced quadratic regression models. The analysis showed that the AO7 decolourization was significantly affected by the suspended activated sludge concentration and the PHA pellet packing volume. Under the optimum conditions (5100 mg/L suspended sludge, 10 mg/L initial AO7 and 20 vol% of PHA pellets), the maximum AO7 decolourization efficiency and rate constant were 96.44 % and 0.3550 h−1, respectively. The high bioactivity of attached activated sludge at a low packing volume demonstrated the potential of the biologically recovered PHA as a biocarrier in retaining a high biomass concentration with a low space requirement.

Influence of salinity on biofilm formation and COD removal efficiency in anaerobic moving bed biofilm reactors.

Anaerobic digestion is widely used for wastewater treatment, but this approach often relies on microbial communities that are adversely affected by high-salinity conditions. This study investigated the applicability of an anaerobic moving bed biofilm reactor (AMBBR) to treating high-salinity wastewater. The removal performance and microbial community were examined under salinity conditions of 1000-3000mg/L, and a soluble chemical oxygen demand (sCOD) removal efficiency of up to 8%±2.74% was achieved at high-salinity. Scanning electron microscopy showed that microorganisms successfully attached onto the polyvinyl alcohol gel carrier, and the extracellular polymeric substances on the biofilm increased at higher salt concentrations. The AMBBR also maintained traditionally accepted levels of total alkalinity and volatile fatty acids for stable wastewater processing under these operating conditions. High-throughput sequencing indicated that Desulfomicrobium and three methanogenic groups were the dominant contributors to sCOD removal. Overall, the results showed that the AMBBR can successfully treat fish factory wastewater under varying salinity conditions.

Effects of high-strength landfill leachate effluent on stress-induced microalgae lipid production and post-treatment micropollutant degradation

This research investigates the effects of landfill leachate effluent concentrations from moving bed biofilm reactor (MBBR) on stress-induced Chlorella vulgaris and Scenedesmus armatus lipid production and post-treatment micropollutant degradation. The effluent concentrations were varied between 25%, 50%, 75%, and 100% (v/v). The landfill leachate influent was treated using two-stage moving bed biofilm reactor under 24 h and 18 h hydraulic retention time (HRT). The results indicated that the effluent concentration was positively correlated with the stress-induced microalgae lipid production in the post-treatment of residual micropollutants. C. vulgaris and S. armatus completely remove residual micropollutants in the effluent. The superoxide dismutase and peroxidase activity were positively correlated with the cellular lipid content. The lipid content of C. vulgaris and S. armatus cultivated in the 18 h HRT effluent were 31–51% and 51–64%, while those in the 24 h HRT effluent were 15–16% and 5–19%. The optimal condition of microalgae cultivation for the post-treatment of residual micropollutants was 50–75% (v/v) effluent concentrations under 18 h HRT, achieving the highest lipid production of 113–116 mg/L for C. vulgaris and 74–75 mg/L for S. armatus. Essentially, the MBBR landfill leachate effluent holds promising potential as a substrate for microalgae lipid production.

Excellent anammox performance driven by stable partial denitrification when encountering seasonal decreasing temperature

Effluent quality deterioration caused by seasonal temperature reductions in wastewater treatment systems using partial anammox technology is a challenge that cannot be ignored. Here, relationships of denitrification and anammox under decreasing temperature were investigated in an anoxic moving bed biofilm reactor (MBBR). Compared with stable partial-denitrification (NO3– → NO2–), the NO2– reduction to N2 was considerably inhibited when the temperature decreased, conversely helping to the competition of NO2– for anammox. Namely, this transformation provided sufficient substrates for anammox bacteria. Although the TIN removal decreased slightly, anammox contribution was robustly maintained at 91.3 ± 6.6 %, even increased. High-throughput sequencing results revealed that anammox bacteria were enriched (0.56 % to 1.22 %). Moreover, qPCR results showed that increased ratio of hzsB/(nirK + nirS) further supported anammox gained an enhancement. This study demonstrated partial-denitrification/anammox process using anoxic MBBR could maintain stable autotrophic nitrogen removal contribution when encountering temperature decrease, providing a new perspective on the application of mainstream anammox.

Potential of food waste-derived volatile fatty acids as alternative carbon source for denitrifying moving bed biofilm reactors

Fossil-based materials such as methanol are frequently used in the denitrification process of advanced biological wastewater treatment as external carbon source. Volatile fatty acids (VFAs) produced by anaerobic digestion of food waste, are sustainable compounds with the potential to act as carbon sources for denitrification, reducing carbon footprint and material costs. In this study, the effectiveness of food waste-derived VFAs (AD-VFA) was investigated in the post-denitrification process in comparison with synthetic VFA and methanol as carbon sources. Acetic acid had the highest rate of disappearance among single tested VFAs with a denitrification rate of 0.44 g NOx-N removed/m2/day, indicating a preferential utilization pattern. While AD-VFA had a denitrification rate of 0.61 mg NOx-N removed/m2/day, sVFA had a rate of 0.57 mg NOx-N removed/m2/day, indicating that impurities in AD-VFA did not play substantial role in denitrification. AD-VFA proved to be promising carbon source alternative for denitrification in wastewater treatment plants.