Nitrification Of Wastewater Research Articles

Feasibility of improving nitrogen removal by integrating the rice straw and zeolite with drainage ditches for farmland runoff control

Natural zeolite and rice straw have been widely used for removing nitrogen (N) from wastewater due to their different N removal mechanisms. In this study, the N removal performances of three substrate systems composed of zeolite (Z), rice straw (R) and their combination (ZR) were assessed for decontaminating farmland runoff characterized by high loads of ammonium - N or nitrate - N besides of a low carbon content. The N-cycling functional genes were also investigated. The results showed that ZR achieved significantly higher ammonium (48.9%–77.7%) and TN (39.7%–65.9%) removal rates than Z and R ( P < 0.05). ZR also exhibited the highest removal rates of nitrate (67.6%–82.7%) and TN (45.5%–62.1%) in nitrate wastewater treatment. The abundances of 16S rRNA and denitrifying genes (including nirK , nirS , narG and napA ) were significantly enhanced in ZR, which partly explained the higher N removal in the ZR than in the Z and R systems. These findings suggest that it is feasible to combine rice straw with zeolite as a substrate of drainage ditches for considerable N removal enhancement in the control of agricultural runoff. • ZR showed the highest nitrogen (N) removal rate when both NH 4 + -N and NO 3 − -N wastewaters were treated. • TN and NO 3 − -N removal in Z was limited by insufficient denitrification due to low organic carbon source. • The combination of zeolite and rice straw significantly increased the abundances of 16S rRNA and denitrifying genes.

ZIF-8 engineered bismuth nanosheet arrays for boosted electrochemical reduction of nitrate.

Removal of nitrate in wastewater is of great importance to environmental protection and humanity. However, the competitive reaction of hydrogen evolution (HER), which could occupy most active sites of the electrocatalyst, is one of the big challenges for nitrate removal. In this study, a novel zeolitic imidazolate framework-8 film engineered bismuth nanosheet electrocatalyst (ZIF-8/Bi-CC) was designed and synthesized for the electrochemical reduction of nitrate. The water contact angle and electrochemical tests demonstrated that the construction of the hydrophobic ZIF-8 film effectively weakened the competition of HER. And the nitrate removal efficiency and ammonium selectivity increased by 25.9% and 34.2% respectively after bismuth nanosheets were embedded into the ZIF-8 film. Besides, the bismuth concentration detection results indicated that the ZIF-8 film as the protective shell could effectively prevent the leaching of bismuth into the solution. More importantly, the final nitrate removal rate of ZIF-8/Bi-CC was close to 90% after 5 h when treating actual garbage fly ash wastewater, the NITRR efficiency stability and the obtained product were confirmed by five electrochemical cycles. The metal-organic framework film engineered electrocatalyst is a promising strategy for designing a new catalyst for the removal of nitrate in industrial wastewater.

Study on the effect of Anammox/Fe0 coupling treatment of nitrate wastewater under neutral conditions

Batch experiments were conducted to explore the effect of Anammox bacteria on the nitrate reduction efficiency of Fe0 under neutral conditions and to analyze the ways of its enhancement. The effects of Fe2+ concentration on the activity of Anammox bacteria in the system were investigated by detecting the nitrate content in the system under neutral conditions. The upflow reactor was set to verify the possibility of stable operation of Fe0/Anammox system in continuous flow. The results showed that in neutral environment, Anammox bacteria can significantly promote the reduction of nitrate by Fe0, and the denitration rate can reach more than 75% under the dual biological and chemical effects. In the continuous flow system of nitrate reduction by Fe0/Anammox bacteria, the stable treatment period was about 7 days. Through regular replacement of iron powder, the denitration rate can be maintained at more than 75% for a long time, and the effluent NH4+, NO2- concentration is low. The treatment of nitrate wastewater by zero-valent iron as a reducing agent has been widely paid attention, but the treatment effect is seriously affected by pH. Anammox bacteria were added to coupling with Fe0 can not only promote each other’s reactivity to adapt to more non-ideal environment, but also reduce secondary pollution, which provides a new idea for the practical application of nitrate wastewater treatment.

Effect of Fe2+ on the performance of Anammox at low temperature

The effects of the addition of a certain concentration of Fe2+ on the activity of anammox bacteria in the system at neutral low temperature were investigated by detecting the contents of nitrate, conductance values and protein in the system. The results showed that when the temperature was set at 15°C and the concentration of Fe2+ was 0.16 mmol/L, the system operated in the best condition. After 60h, the denitration rate increased by 40%, the electrical conductivity value decreased the fastest, and the protein content increased by 24.5 mg/g compared with the control group. Zero valent iron has been widely concerned as a reducing agent for the treatment of nitrate wastewater, but the treatment efficacy is severely affected by temperature. The addition of anammox bacteria coupled with Fe0 can not only mutually promote the reaction activity to adapt to more non ideal environments but also reduce the secondary pollution, which provides a new idea for the practical application of nitrate wastewater treatment.

Development of novel denitrifying nitrite accumulation and phosphorus removal (DNAPR) process for offering an alternative pretreatment to achieve mainstream Anammox

For achieving mainstream anaerobic ammonium oxidation (Anammox), there is a need to achieve organic carbon and phosphorus removal meanwhile supplying nitrite (NO2–-N). Based on this demand, a novel anaerobic/anoxic/aerobic operated denitrifying nitrite accumulation and phosphorus removal (DNAPR) process was proposed for treating synthetic municipal and nitrate (NO3–-N) wastewaters simultaneously (volume ratio of 5:1). By adjusting influent composition, discharging anaerobic-end supernatant, shortening anoxic duration, and adding a short aerobic stage, DNAPR process achieved promising and stable nitrate-to-nitrite transformation (78.35%) and phosphorus removal (98.34%) performance. Moreover, effluent with chemical oxygen demand of 16.63 mg/L, nitrite of 54.16 mg/L, orthophosphate of 0.37 mg/L, and nitrite to ammonia ratio of 1.3 were finally obtained after 141-day operation. Microbiological analysis showed that Thauera (34.9%) and unclassified_f_Rhodobacteraceae (6.79%) were both responsible for DNAPR. Therefore, DNAPR, serving as promising alternative pretreatment, might possess significance for achieving mainstream Anammox.

Toward Long-Term Accurate and Continuous Monitoring of Nitrate in Wastewater Using Poly(tetrafluoroethylene) (PTFE)-Solid-State Ion-Selective Electrodes (S-ISEs).

Long-term accurate and continuous monitoring of nitrate (NO3-) concentration in wastewater and groundwater is critical for determining treatment efficiency and tracking contaminant transport. Current nitrate monitoring technologies, including colorimetric, chromatographic, biometric, and electrochemical sensors, are not feasible for continuous monitoring. This study addressed this challenge by modifying NO3- solid-state ion-selective electrodes (S-ISEs) with poly(tetrafluoroethylene) (PTFE, (C2F4)n). The PTFE-loaded S-ISE membrane polymer matrix reduces water layer formation between the membrane and electrode/solid contact, while paradoxically, the even more hydrophobic PTFE-loaded S-ISE membrane prevents bacterial attachment despite the opposite approach of hydrophilic modifications in other antifouling sensor designs. Specifically, an optimal ratio of 5% PTFE in the S-ISE polymer matrix was determined by a series of characterization tests in real wastewater. Five percent of PTFE alleviated biofouling to the sensor surface by enhancing the negative charge (-4.5 to -45.8 mV) and lowering surface roughness (Ra: 0.56 ± 0.02 nm). It simultaneously mitigated water layer formation between the membrane and electrode by increasing hydrophobicity (contact angle: 104°) and membrane adhesion and thus minimized the reading (mV) drift in the baseline sensitivity ("data drifting"). Long-term accuracy and durability of 5% PTFE-loaded NO3- S-ISEs were well demonstrated in real wastewater over 20 days, an improvement over commercial sensor longevity.

Optimization of nitrate and selenate reduction in an ethanol-fed fluidized bed reactor via redox potential feedback control

Electron donors are a major cost-factor in biological removal of oxyanions, such as nitrate and selenate from wastewater. In this study, an online ethanol dosing strategy based on feedback control of oxidation-reduction potential (ORP) was designed to optimize the performance of a lab-scale fluidized bed reactor (FBR) in treating selenate and nitrate (5 mM each) containing wastewater. The FBR performance was evaluated at various ORP setpoints ranging between −520 mV and −240 mV (vs. Ag/AgCl). Results suggested that both nitrate and selenate were completely removed at ORPs between −520 mV and −360 mV, with methylseleninic acid, selenocyanate, selenosulfate and ammonia being produced at low ORPs between −520 mV and −480 mV, likely due to overdosing of ethanol. At ORPs between −300 mV and −240 mV, limited ethanol dosing resulted in an apparent decline in selenate removal whereas nitrate removal remained stable. Resuming the ORP to −520 mV successfully restored complete selenate reduction. An optimal ORP of −400 mV was identified for the FBR, whereby selenate and nitrate were nearly completely removed with a minimal ethanol consumption. Overall, controlling ORP via feedback-dosing of the electron donor was an effective strategy to optimize FBR performance for reducing selenate and nitrate in wastewater.

A microbial sensor platform based on bacterial bioluminescence (luxAB) and green fluorescent protein (gfp) reporters for in situ monitoring of toxicity of wastewater nitrification process dynamics

To avoid the upset of nitrification process in wastewater treatment plants, monitoring of influent toxic chemicals is essential for stable operation. Toxic chemical compounds can interfere with the biological nitrogen removal, thus affecting plant efficiency and effluent water quality. Here we report the development of fluorescence and bioluminescence bioassays, based on E. coli engineered to contain the promoter region of ammonia oxidation pathway (AmoA1) of Nitrosomonas europaea and a reporter gene (lux or gfp). The fluorescence or bioluminescence signal was measured with newly designed optical devices. The microbial sensors were tested and validated at different concentrations of nitrification-inhibiting compounds such as allylthiourea, phenol, and mercury. The signal decrease was immediate and proportional to inhibitor concentration. The developed bacterial bioassays could detect the inhibition of the nitrification process in wastewater for allylthiourea concentrations of 1 μg/L for E.coli pMosaico-Pamo-gfp and 0.5 μg/L for E.coli pMosaico-Pamo-luxAB. The results were confirmed using water from a wastewater plant, containing nitrification-inhibiting compounds.

Rapid start-up of partial nitrification process using benzethonium chloride—a novel nitrite oxidation inhibitor

Benzethonium chloride (BZC) is an antibacterial compound with extensive applications in various anti-infective products. However, the feasibility of attaining partial nitrification of municipal wastewater using BZC has not been reported. In this work, BZC was used for the first time to attain partial nitrification. Batch experiments indicated nitrite oxidizing bacteria (NOB) was more vulnerable to BZC than ammonia oxidizing bacteria (AOB). When activated sludge was treated only once with 0.023 g BZC·(g MLSS)-1 for 18 h, partial nitrification was attained at the 29th cycle with NAR of 97.46% and sustained 91 cycles in stability tests. Complimentary DNA sequencing analysis revealed the suppression of Nitrospira was the reason for partial nitrification. Oligotyping analysis indicated AOB could likely resist to BZC by both the species shifts and development of tolerance, while most NOB species could not adapt to BZC. This study revealed the feasibility of BZC as a novel NOB inhibitor.

Microbial community succession, species interactions and metabolic pathways of sulfur-based autotrophic denitrification system in organic-limited nitrate wastewater

Elemental sulfur (S0) introduction could achieve the co-existence of heterotrophic denitrification (HDN) and autotrophic denitrification (ADN) in practical organic-limited nitrate wastewater treatment. Until now, changes in key functional species, metabolic pathways and microbial products in the succession process of microbialcommunities based on different of pollutant concentration and trophic conditions are still unclear. In present study, high-efficiency of total nitrogen (TN) removal achieved in S0-based ADN bioreactor at influent nitrate of 30–240 mg/L. Content of proteins and polysaccharides in extracellular polymeric substances (EPS) declined with nitrate loads increased. The key functional heterotrophic denitrifiers (Hyphomicrobium, Trichococcus, Rivibacter) and autotrophic biotope (Thiobacillus, Thiomonas, Ferritrophicum, Flavobacterium, Stenotrophomonas, Cloacibacterium and Pseudoxanthomonas) jointly contributed to high nitrogen removal efficiency at different nitrate loads. Furthermore, network analysis verified that symbiotic relationships accounted for the major proportion (88.3%) of the microbial network. The enhanced of nitrogen and sulfur metabolism improved nitrogen removal and S0-based autotrophic denitrification capacity.

High efficient assimilation of NO₃⁻-N with coproduction of microalgal proteins by Chlorella pyrenoidosa

The aim of this study was to establish a novel technology using microalgae for NO₃⁻ removal from high concentration wastewater and conversion to algal proteins. The effects of cultivation modes and illumination modes on the biomass yield, NO₃⁻ assimilation rate and algal protein yield were first investigated in shaking flasks for mixotrophic cultivation of Chlorella pyrenoidosa, and subsequently the scale-up verification in 5-L photo fermenter was successfully conducted. Fed-batch cultivation without medium recycling was the best cultivation mode in shaking flask system, in which the highest biomass yield (35.95 g/L), the average NO₃⁻ assimilation rate (2.06 g/(L·d)) and algal protein content (up to 42.44% of dry weight) were achieved. By using a staged increase of light intensity as illumination modes, the specific growth rate of cells could be significantly promoted to the highest (0.65 d⁻¹). After a 128-hour continuous cultivation in a 5-L photo fermenter, the highest biomass yield and the average NO₃⁻ assimilation rate were reached to 66.22 g/L and 4.38 g/(L·d) respectively, with the highest algal protein content at 47.13% of dry weight. Our study could provide a photo fermentation technology of microalgae for highly efficient treatment of waste industrial nitric acid and/or high concentration nitrate wastewater. This microalgae-based bioconversion process could coproduce protein-rich microalgal biomass, which facilitates the resource utilization of these type wastewater by trash-to-treasure conversion.

Effects of temporary external voltage on the performance and community of microbial fuel cells.

This study evaluated the effects of temporary external voltage on the performance of two-chambered microbial fuel cells (MFC) that use nitrate wastewater as a substrate. Results indicate that the external voltage affected the performance of the MFC during their operation, and this effect remained even after the voltage was removed. The degradation efficiency of the chemical oxygen demand increased in the MFC under external voltages of 0.5, 0.8, and 1.1 V, and the optimal applied voltage was 1.1 V. Compared with the control group without external voltages, the MFC under a voltage of 1.1 V achieved higher current densities and efficiency of nitrate removal during their operation. The MFC with an applied voltage of 1.1 V also achieved the highest maximum power density of 2,035.08 mW/m3. The applied voltages of 0.5 and 0.8 V exerted a positive effect on the performance of the MFC. High-throughput sequencing was used to explore the anode and cathode biofilms. Results showed that the influence was highly associated with microbial community in bio-anode. The predominant functional family changed from Methanotrichaceae during start-up to Flavobacteriaceae in a steady phase.

Simultaneous heterotrophic nitrification and aerobic denitrification of wastewater in granular reactor: Microbial composition by next generation sequencing analysis

Dairy effluents contain limited nitrogen for biological treatment. In the present study a cheese whey wastewater was supplemented with ammonia to obtain suitable COD:N ratios. The effects of the organic load and micronutrients on the biological nitrogen removal process were analyzed in aerobic granular sequential batch reactors (SBRs). Better nitrifying activity (5.04 mg N.(L.h)−1) was achieved at COD:N = 100:12, when micronutrients were added. In this condition, simultaneous nitrification- denitrification led to a higher inorganic nitrogen removal. Aerobic denitrification was driven by intracellular glycogen. In absence of micronutrients, nitrification took place when the organic load was decreased (COD:N = 100:22). The microbial community was analyzed by next-generation sequencing technology. Nitrification was attributed to heterotrophic nitrifiers. Bacteria belonging to Niabella and Diaphorobacter genera and to Planctomycetales order are the main candidates responsible for the nitrification process. Co-treatment of dairy and ammonium-rich wastewater constitutes a promise strategy for the biological treatment of dairy wastewaters.

Intensified simultaneous nitrification and denitrification performance in integrated packed bed bioreactors using PHBV with different dosing methods.

To explore an effective approach of simultaneous nitrification and denitrification in wastewater with low C/N ratios, integrated packed bed bioreactors based on poly(3-hydroxybutyrate-hydroxyvalerate) (PHBV) with different dosing methods were designed. The removal efficiency of NH4+-N in bioreactor with aeration was 88.62%, and higher NO3--N removal efficiency was observed in bioreactor filled with grainy PHBV (95.21%) than bioreactor filled with strip PHBV (93.34%). Microbial study indicated that microbes harboring amoA and nirS genes preferred to attach on the surface of ceramsite, and significant differences in microbial community compositions at phylum and genus levels were observed. To summarize, it is feasible to utilize grainy PHBV for simultaneous and efficient removal of NH4+-N and NO3--N from wastewater with low C/N ratios.

Evaluation of cold-weather wastewater nitrification technology for removal of polar chemicals of emerging concern from rural Manitoba wastewaters

Aerated lagoons, typically used by small communities, often provide limited removal of wastewater nutrients. Given increasingly stringent wastewater standards, it is imperative that effective, but economical and easy-to-operate, treatment technologies be developed. The Submerged Attached Growth Reactor (SAGR®) is a treatment process developed to perform nitrification near freezing temperatures. Previous tests on full-scale installations have shown that SAGR could consistently remove ammonia to below current Canadian standards and provide additional total suspended solids and biochemical oxygen demand removal. In this study, we evaluated removal of polar chemicals of emerging concern (CECs), including pharmaceuticals, personal care products, and pesticides, at SAGR installations in two Manitoba First Nations communities (MCN and LPFN) under cold winter conditions. Both showed some removal of diclofenac, naproxen, clarithromycin, metoprolol, and trimethoprim, likely by biotransformation. Average naproxen removal was 21% (2.53 × 103 ng L−1) in MCN and 64% (1.58 × 103 ng L−1) in LPFN. Atenolol was well-removed by SAGR, by 80% on average (range of 64%–94%). Clarithromycin, metoprolol, and trimethoprim removal was similar within and between systems, ranging from 54% to 76% (30.8–3.07 × 102 ng L−1 removed). Carbamazepine was detected in nearly all samples, but was not well-removed, consistent with other treatment studies. Overall, results showed that SAGR technology could moderately remove CECs, while providing the designed treatment performance for other parameters. This work will help to improve our understanding of wastewater treatment in small and/or remote communities with limited infrastructure and challenging cold-weather conditions.

Composite of chitosan and bentonite cladding Fe–Al bimetal: Effective removal of nitrate and by-products from wastewater

Chitosan was used as crosslinking agent to load bimetal particles onto bentonite. The Fe–Al bimetal chitosan bentonite (Fe–Al bimetal @ bent) complex was prepared for the efficient removal of nitrate from wastewater and its by-products at low temperature. The samples were characterized by Scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), X-Ray Diffraction (XRD), Zeta potential, X-ray photoelectron spectroscopy (XPS) and Brunauer–Emmett–Teller (BET) surface area and Energy Dispersive X-ray Detector (EDX). SEM and EDX showed that Fe0 was deposited on the surface of aluminum, the Fe–Al bimetal were surrounded by chitosan and bentonite. XRD showed that Al can effectively protect the reactivity of Fe. The experimental results of nitrate removal showed that pH was the main factor affecting on nitrate removal rate and performance. The removal efficiency of nitrate wastewater with a concentration of 50 mg/L was approximately 90% in 60min. Fe–Al bimetal @ bent has better nitrate removal performance and faster reduction rate at low temperature(2–7 °C) than normal temperature (25 °C). The reason was that chitosan, bentonite and bimetal have excellent synergistic effect. It can effectively improve the reaction rate, pH buffering capacity, reduce secondary pollution and total nitrogen (TN). Fe–Al bimetal @ bent has better N2 selectivity than Fe–Al bimetal.

Stable Nitrite Accumulation and Phosphorus Removal from High-nitrate and Municipal Wastewaters in a Combined Process of Partial Denitrification and Denitrifying Phosphorus Removal (PD-DPR)

In this study, a novel process combining partial denitrification (PD, NO3--N→NO2--N) and denitrifying phosphorus removal (DPR) in an anaerobic-anoxic-aerobic sequencing batch reactor (SBR) was developed. By comprehensively controlling the influent C/N ratio, anaerobic drainage ratio, and anoxic duration, the nitrite accumulation and phosphorus removal performance of a system treating high-strength nitrate and municipal wastewaters was investigated. The results showed that, after 140 days, the nitrate-to-nitrite transformation ratio (NTR) was 80.1%, and PO43--P removal efficiency was 97.64%. In the anaerobic stage (180 min), glycogen-accumulating organisms (GAOs) and phosphorus-accumulating organisms (PAOs) efficiently utilized the carbon source in municipal wastewater to enhance intracellular carbon storage. In the anoxic stage (150 min), denitrifying GAOs (DGAOs) and heterotrophic denitrifying bacteria (DOHOs) carried out endogenous and exogenous short-range denitrification, respectively, to achieve stable nitrite accumulation; simultaneously, denitrifying PAOs (DPAOs) carried out denitrifying phosphorus uptake to achieve efficient phosphorus removal. In the aerobic stage (10 min), without initiating ammonia/nitrite oxidation, PAOs absorbed excessive phosphorus, which improved the phosphorus removal performance of the system. The effluent NO2--N/NH4+-N of a ratio of 1.31:1 (close to the theoretical value of ANAMMOX process, 1.32:1), with little PO43--P and COD (0.30 and 12.94 mg·L-1), meets the requirements for deep-level nitrogen removal by coupling with ANAMMOX process.

Achieving partial denitrification-anammox in biofilter for advanced wastewater treatment

Recently, partial denitrification (PDN) - anaerobic ammonium oxidation (anammox) process has been widely studied in activated sludge for nitrate wastewater treatment. However, achieving PDN-Anammox in biofilter for domestic wastewater treatment was never reported. In this study, two lab-scale PDN biofilter and Anammox biofilter were built up to treat simulated domestic wastewater. The results showed that stable nitrogen removal performance was kept with averaged effluent nitrogen of 10.2 mg/L. Stable nitrite accumulation performance was achieved with low abundance of nitrite reductase gene, while influent composition influenced nitrogen transformation pathway in PDN biofilter. When treating domestic wastewater, nitrification and partial denitrification led to the higher nitrite accumulation ratio of 75.4%. The percentage contribution of anammox biofilter was 74.6% for nitrogen removal, and Candidatus Brocadia was dominant genus. After long-term operation, limited substrate concentration caused interspecific competition among various anammox bacteria, leading to an increasing proportion of Candidatus Brocadia fulgida. PDN-Anammox biofilter is a feasible process to advanced wastewater treatment, which could save aeration consumption and carbon source addition, and reduce sludge production.

A novel partial nitrification-synchronous anammox and endogenous partial denitrification (PN-SAEPD) process for advanced nitrogen removal from municipal wastewater at ambient temperatures

Mainstream anammox still faces the challenges of non-ideal NO2−/NH4+ ratios and excess nitrate resulted from the instability of partial nitrification (PN) in municipal wastewater. To address these problems, in this study, we developed a novel two-sludge process that combined PN with synchronous anammox and endogenous partial denitrification (SAEPD); the process was tested with pre-treated domestic sewage at ambient temperatures for 205 d. High nitrogen removal efficiency of 91.2% was achieved with an influent C/N ratio of 1.7 at 15.4 °C; the success was attributed to the fact that EPD replenished the deficient nitrite by reducing nitrate and the excess nitrite was further reduced to nitrogen gas. With a non-ideal NO2−/NH4+ ratio of 0.89, the contribution of the SAEPD-sequencing batch reactor (SBR) during the anoxic stage reached 98.2% and the proportional contributions of the anammox and denitrification pathways were 77.2% and 22.8%, respectively. Although the low nitrite accumulation (66.1%) caused 10.8 mg N/L of nitrate to be transported into the SAEPD-SBR and the anammox reaction also converted 20% of nitrite to nitrate, only 1.1 mg N/L of nitrate remained in the effluent. High-throughput sequencing analysis revealed that although NH2OH was added, some genera of nitrite-oxidizing bacteria (0.73%) remained in the PN-SBR and potentially resulted in the oxidation of nitrite to nitrate. In the SAEPD-SBR, anammox and endogenous denitrifying bacteria co-existed and synergistically achieved the removal of ammonium, nitrite, and nitrate. Overall, the PN-SAEPD process has great potential for achieving cost-effective and energy-efficient municipal wastewater treatment.

Nutrient removal by alginate‐immobilized Chlorella vulgaris: response to different wastewater matrices

AbstractBACKGROUNDImmobilized algae are a promising tool to treat wastewater within a short time (&lt;12 h) and simplify biomass harvesting compared with suspended algae. The potential of alginate‐entrapped Chlorella vulgaris to bioremediate secondary (with and without nutrient supplementation), primary and two lagoon municipal wastewaters was investigated. The capability of the system to adapt to these wastewaters was analysed by determining biotic and abiotic nutrient removal, and further evaluated by comparison with suspended cells.RESULTSThe algal nitrogen (N) content (4.6–7.8 wt%) was closely related to the wastewater ammonium concentration (R2 = 0.97). The algal cells did not adapt N uptake as effectively to wastewater nitrate concentration because both abiotic N and phosphorus (P) removal increased. The algal P content (1.2–3.2 wt%) varied in response to the wastewater P and was inversely related to the initial cellular P content. The algae thus adapted nutrient uptake to the wastewater N:P level and ratio when ammonium predominated. Biomass production (35–73 mg L‐1 d‐1) increased with dissolved organic and inorganic carbon with little impact from other wastewater characteristics. Immobilization did not affect N and P uptake per cell compared with suspended algae.CONCLUSIONDecoupling biotic and abiotic removal showed adaptation to the N:P of the wastewater and luxury P uptake had significant impact during treatment of different wastewater matrices, these traits were not affected by immobilization. Immobilization enables increased N and P removal rates compared with suspended algal systems as nutrient uptake per cell is not affected and higher concentrations of algal biomass within the reactor are facilitated. © 2020 Society of Chemical Industry