Enhanced heavy metal stabilization and phosphorus retention during the hydrothermal carbonization of swine manure by in-situ formation of MgFe2O4.

Hydrothermal carbonization is an efficient technique for the disposal of livestock manure, enabling its harmless treatment, quantity reduction, and resourceful utilization. Co-hydrothermal of modified materials facilitates the production of more valuable carbonaceous materials. However, further exploration is needed to understand their potential impact on the environmental risks associated with livestock manure disposal and the application of products derived from it. Therefore, the carbonization degree, heavy metals stabilization, and phosphorus retention during the hydrothermal treatment of swine manure were systematically investigated in this study under the influence of in-situ formed MgFe2O4. The results revealed that the in-situ formation of MgFe2O4 improved the dehydration and decarboxylation of organic components in swine manure, thereby improving its carbonization degree. Furthermore, both hydrothermal carbonization and MgFe2O4 modified hydrothermal carbonization resulted in an enhanced stabilization of heavy metals, leading to a significant reduction in their soluble/exchangeable fraction and reducible fraction. Phosphorus was predominantly retained in the hydrochars, with the highest retention rate reaching 88%, attributed to the significant decrease in soluble and exchangeable phosphorus fractions facilitated by the in-situ formation of MgFe2O4. Moreover, MgFe2O4 modified hydrochars exhibited remarkable adsorption capacity for Pb(II) and Cu(II) without any leaching of heavy metals. Overall, the findings indicated that the in-situ formation of MgFe2O4 positively influenced the hydrothermal of swine manure, improving certain economic benefits in its practical application.

In-situ remediation of zinc contaminated soil using phosphorus recovery product: Hydroxyapatite/calcium silicate hydrate (HAP/C-S-H).

This work discussed the feasibility and stability of utilizing C-S-H phosphorus recovered products, HAP/C-S-H, to remove Zn(Ⅱ) from aqueous solution and in-situ immobilize Zn(Ⅱ) in contaminated soil. The removal mechanisms of Zn(Ⅱ) by HAP/C-S-H were relatively complex, combining multiple reactions including electrostatic attraction, ion exchange, surface complexation and (co-)precipitation. The removal rate of Zn(Ⅱ) by HAP/C-S-H raised with the increase of pH value, reaching 99.47% at pH of 8 in aqueous solution. The ion strength of background solution negatively affected the adsorption efficiency. The pseudo-second-order model and Langmuir model were more suitable to fit the Zn(Ⅱ) adsorption experimental data for the adsorbent. The adsorption process was endothermic and spontaneous naturally according to thermodynamic parameter. The maximum adsorption capacity of HAP/C-S-H can reach 114.0 mg/g at 308 K. After 28 days of immobilization, the release of Zn(Ⅱ) in soil with HAP/C-S-H remarkably decreased to 0.6 mg/L, compared with control group (2.9 mg/L). BCR sequential extraction results indicated that HAP/C-S-H could convert acid-soluble Zn(Ⅱ) into reducible and residual Zn(Ⅱ), reducing the bioavailability and ecotoxicity of Zn(Ⅱ) in contaminated soil. pH-dependent leaching tests revealed that the soil with HAP/C-S-H had stronger resistance to acid impact.

Enhanced visible light photo-Fenton-like degradation of tetracyclines by expanded perlite supported FeMo3Ox/g-C3N4 floating Z-scheme catalyst.

In the conventional Fenton system, the relatively low efficiency of Fe (II) regeneration is a significant drawback. To address this shortcoming, a novel floating Z-scheme photo-Fenton catalyst FeMo3Ox/g-C3N4/EP was prepared by a facile dip-calcination method, in which iron and molybdenum oxides with mixed valence states (FeMo3Ox) and graphitic carbon nitride (g-C3N4) were loaded on the expanded perlite. The removal efficiencies reached the maximum at 98.0%, 93.1% and 97.1% for tetracycline, oxytetracycline and chlortetracycline, respectively, after 60 min dark adsorption and 60 min photo-Fenton process. The aid of dual ion (Fe and Mo) synergy system and photoreduction by Z-scheme photocatalyst enhanced the Fe (II) regeneration, resulting in the excellent performance. Radical scavenger experiment, electron spin resonance spectra (ESR) and X-ray photoelectron spectra (XPS) were used to confirm the mechanism of free radicals' formation and Fe/Mo redox cycling. ·OH, ·O2- and 1O2 played important roles in the pollutant's degradation, while the generation of ·O2- was enhanced due to the floatability in this system. The possible degradation pathways of TC were put forward according to the results of mass spectrum and Orbital-Weighted Fukui Function. Overall, this work provides new insights on the cooperation between iron-based mix oxides and semiconductor in the photo-Fenton system.

Remediation of artificially contaminated soil and groundwater with copper using hydroxyapatite/calcium silicate hydrate recovered from phosphorus-rich wastewater.

Excessive copper (Cu) in contaminated soil and groundwater has attracted continuous attentions due to the bioaccumulation and durability. In this study, the feasibility of remediation of heavy metal pollution in soil and groundwater was investigated using hydroxyapatite/calcium silicate hydrate (HAP/C-S-H) recovered from phosphorus-rich wastewater in farmland. The results show that the pH has a strong effect on copper removal from Cu-contaminated groundwater but the impact of ion strength on the removal is weak. In general, high pH and low ion strength give better results in copper removal. Kinetic and isotherm data from the study fit well with Pseudo-second-order kinetic model and Langmuir isotherm model, respectively. The maximum adsorption capacity of HAP/C-S-H (138 mg/g) was higher than that of C-S-H (90.3 mg/g) when pH value, temperature, and ionic strength were 5, 308 K, and 0.01 M, respectively. Thermodynamics results indicate that Cu removal is a spontaneous and endothermic process. X-ray diffraction (XRD) results show that the mechanism of copper removal involves physical adsorption, chemical precipitation and ion exchange. For the remediation of Cu-contaminated soil, 76.3% of leachable copper was immobilized by HAP/C-S-H after 28 d. Acid soluble Cu, the main contributor to biotoxicity, decreased significantly while reducible and residual Cu increased. After immobilization, the acid neutralization capacity of the soil increased and the dissolution of copper was substantially reduced in near-neutral pH. It can be concluded that HAP/C-S-H is an effective, low-cost and eco-friendly reagent for in-situ remediation of heavy metal polluted soil and groundwater.

Phosphorus recovery from aqueous solution via a microbial electrolysis phosphorus-recovery cell.

The coming global phosphorus (P) crisis makes P recovery from wastewater become an inevitable choice. Hydroxyapatite (HAP) crystallization is an important approach for P recovery, but its requirements for high alkali and acid are unaffordable. Thus, a microbial electrolysis phosphorus-recovery cell (MEPRC) was developed to cut down the alkali cost via raising the wastewater pH (over 11) in the cathode chamber, and the acid cost via producing acid in the acid-production chamber. HAP was confirmed to be the final recovered products, and P recovery efficiency over 80% was achieved at 24-h operation. To optimize the P recovery performance of this system, the effects of the key factors including applied voltage, P initial concentration and Ca/P ration were investigated. High voltage could promote the rate of P recovery but had slight effect on the eventual recovery efficiency (elevated from 88.5 to 91.1%). High P initial concentration (15.0 mM) could slow down the pH elevation, contributing to the low P recovery efficiency (50.1%) within 24 h. However, prolonging the operation could break the buffering and obtain a satisfactory P recovery efficiency (87.2%) at 36 h. Besides, sufficient calcium ions were favorable to the P recovery. In addition, P recovery cost analyses of the MEPRC indicated that it might be a low-cost technology for P recovery. Moreover, the simultaneously produced acid could be used to neutralize the effluent after P recovery with high pH value. These results demonstrate the feasibility of MEPRC for cost-effective P recovery from wastewater.

Bioelectrochemical acidolysis of magnesia to induce struvite crystallization for recovering phosphorus from aqueous solution.

A novel struvite crystallization method induced by bioelectrochemical acidolysis of magnesia (MgO) was investigated to recover phosphorus (P) from aqueous solution using a dual-chamber microbial electrolysis cell (DMEC). Magnesium ion (Mg2+) in the anolyte was firstly confirmed to automatically migrate from the anode chamber to the cathode chamber, and then react with ammonium (NH4+) and phosphate (PO43-) in the catholyte to form struvite. Recovery efficiency of 17.8%-60.2% was obtained with the various N/P ratios in the catholyte. When MgO (low solubility under alkali conditions) was added into the anolyte, the bioelectrochemical acidolysis of MgO naturally took place and the released Mg2+ induced struvite crystallization in the cathode chamber for P recovery likewise. Besides, there was a strong linear positive correlation between the recovery efficiency and the MgO dosage (R2 = 0.935), applied voltage (R2 = 0.969) and N/P ratio (R2 = 0.905). Increasing the applied voltage was found to enhance the P recovery via promoting the MgO acidolysis and the released Mg2+ migration, while increasing the N/P ratio in the catholyte enhanced the P recovery via promoting the struvite crystallization. Moreover, the electrochemical performance of the system was promoted due to more stable anolyte pH and lower pH gradient between the two chambers. Current density was promoted by 10%, while the COD removal efficiency was improved from 78.2% to 91.8% in the anode chamber.

Electrochemical acidolysis of magnesite to induce struvite crystallization for recovering phosphorus from aqueous solution.

A novel struvite crystallization method induced by electrochemical acidolysis of cheap magnesite was investigated to recover phosphorus from aqueous solution. Magnesite was confirmed to continuously dissolve in the anolyte whose pH stabilized at about 2. Driven by the electrical field force, over 90% of the released Mg2+ migrated to the cathode chamber via passing through the cation exchange membrane. The pH of the phosphate-containing aqueous solution in the cathode chamber was elevated to the appropriate pH fit for struvite crystallization. The products were identified as struvite crystals by scanning electron microscopy and X-ray diffraction. Increasing the magnesite dosage from 0.83 to 3.33 g L-1 promoted the phosphorus recovery efficiency from 2.2% to 78.3% at 3 d, which was attributed to sufficient Mg2+ supply. Increasing the applied voltage from 3 to 6 V improved the recovery efficiency from 43.6% to 76.4% at 1 d, since the enhanced current density of the electrochemical system markedly accelerated both the magnesite acidolysis and the catholyte pH elevation. The initial catholyte pH between 3 and 5 was found to benefit the phosphorus recovery due to the final catholyte pH fit for the struvite crystallization.

Assessing membrane biofouling and its gel layer of anoxic/oxic membrane bioreactor for megacity municipal wastewater treatment during plum rain season in Yangtze River Delta, China.

This study assessed membrane biofouling and its gel layer of anoxic/oxic membrane bioreactor (A/O-MBR) for megacity municipal wastewater treatment during plum rain season, which was continuous rainy weather, in Yangtze River Delta, China. A laboratory-scale A/O-MBR was operated to treat the municipal wastewater from Quyang wastewater treatment plant, which located at the typical megacity of Shanghai in Yangtze River Delta, from April to July accompanying with plum rain season. As reactor performance showed, CODCr, NH4+-N, TN, TP of the influent gradually decreased during plum rain season, and inhibited pollutant removal due to organic carbon shortage. However, dissolve inorganic carbon and inorganic components in mixed liquid had an obvious increase under rainy weather. Membrane filtration results indicated that plum rain season enhanced pore blocking behavior, further leading to the serious membrane biofouling but inhibiting gel layer formation. Additionally, gel layer analysis predicted that plum rain season led to plenty of inorganic components and precipitate flew into A/O-MBR reactor. Inorganic components with elements of Ca, Mg Ba, Fe, Al and Si seriously blocked membrane pores. Those components also accumulated into gel layer in the form of SiO2, CaCO3, CaSiO3, MgNH4PO4, BaCO3, AlPO4, etc. Consequently, plum rain season enhanced pore blocking behavior and led to severe membrane biofouling but with the inhibition of gel layer formation.

The distribution of phosphorus and its transformations during batch growth of Synechocystis.

Phosphorus (P) is an essential nutrient that affects the growth and metabolism of microalgal biomass. Despite the obvious importance of P, the dynamics of how it is taken up and distributed in microalgae are largely undefined. In this study, we tracked the fate of P during batch growth of the cyanobacterium Synechocystis sp. PCC 6803. We determined the distribution of P in intracellular polymeric substances (IPS), extracellular polymeric substances (EPS), and soluble microbial products (SMP) for three initial ortho-phosphate concentrations. Results show that the initial P concentration had no impact on the production of biomass, SMP, and EPS. While the initial P concentration affected the rate and the timing of how P was transformed among internal and external forms of inorganic P (IP) and organic P (OP), the trends were the same no matter the starting P concentration. Initially, IP in the bulk solution was rapidly and simultaneously adsorbed by EPS (IPEPS) and taken up as internal IP (IPint). As the bulk-solution's IP was depleted, desorption of IPEPS became the predominant source for IP that was taken up by the growing cells and converted into OPint. At the end of the 9-d batch experiments, almost all P was OP, and most of the OP was intracellular. Based on all of the results, we propose a set of transformation pathways for P during the growth of Synechocystis. Key is that EPS and intracellular P pool play important and distinct roles in the uptake and storage of P.

[Efficacy of A2/O-MBR Combined Process in Wastewater Treatment and the Characteristics of Membrane Fouling].

The hydrophilic modification of PVA composite membrane was applied in the reversed A2/O-MBR process to treat wastewater, the removal efficacy of COD, NH4(+) -N, TN, TP, turbidity and performance of composite membrane were investigated. The results indicate that the average removal rates of COD, NH4(+) -N and TP were higher than 90%, 95% and 80% under different reflux ratio, respectively. The reflux ratio had large impact on TN removal rate: when the reflux ratio was 100%, the removal rate was low; when the reflux ratio increases the range from 100% to 300%, the removal rate was correspondingly increased. Under the efficient interception of membrane, water turbidity was always less than 0.05NTU, and the composite film was controlled at (12 ± 0.5) L x (m2 x h)(-1) flux, the operation was uninterrupted for 52 days without any cleaning process of the membrane, the average rate of membrane fouling is 13.22 Pa x h(-1) and the process of membrane fouling was very slow. After FTIR analysis, we confirmed that polysaccharide and protein is a main composition of organic pollutants. LB is further proved to be the main pollutants from micro acting force between the membrane and the pollutants, which is consistent with FTIR analysis.

Nutrient release, recovery and removal from waste sludge of a biological nutrient removal system.

The uncontrolled release of nutrients from waste sludge results in nitrogen and phosphorus overloading in wastewater treatment plants when supernatant is returned to the inlet. A controlled release, recovery and removal of nutrient from the waste sludge of a Biological Nutrient Removal system (BNR) are investigated. Results showed that the supernatant was of high mineral salt, high electrical conductivity and poor biodegradability, in addition to high nitrogen and phosphorus concentrations after the waste sludge was hydrolysed through sodium dodecyl sulphate addition. Subsequently, over 91.8% of phosphorus and 10.5% of nitrogen in the supernatants were extracted by the crystallization method under the conditions of 9.5 pH and 400 rpm. The precipitate was mainly struvite according to X-ray diffraction and morphological examination. A multistage anoxic-oxic Moving Bed Biofilm Reactor (MBBR) was then adopted to remove the residual carbon, nitrogen and phosphorus in the supernatant. The MBBR exhibited good performance in simultaneously removing carbon, nitrogen and phosphorus under a short aeration time, which accounted for 31.25% of a cycle. Fluorescence in situ hybridization analysis demonstrated that nitrifiers presented mainly in floc, although higher extracellular polymeric substance content, especially DNA, appeared in the biofilm. Thus, a combination of hydrolysis and precipitation, followed by the MBBR, can complete the nutrient release from the waste sludge of a BNR system, recovers nutrients from the hydrolysed liquor and removes nutrients from leftovers effectively.

Enhanced struvite recovery from wastewater using a novel cone-inserted fluidized bed reactor.

The feasibility of struvite recovery at low (12.5 mg/L) and high (120 mg/L) phosphorus concentrations was studied by constructing a novel fluidized bed reactor with cones (FBRwc) and without cones (FBRwoc). The crystallization process was continuously operated for 133 days under different hydraulic retention times (HRT = 1-10 hr), pH (7.5-10), and molar ratios of Mg/P (0.75-1.75), N/P (1-10) and Ca/Mg (0-2). The optimum operating conditions of HRT, pH, Mg/P and N/P molar ratios were found to be 2 hr, 9, 1.25, and 7.5, respectively. Under these optimum conditions, the phosphorus precipitation efficiencies of FBRwc were 93% for low and 98% for high phosphorus influent; however, the efficiencies were 78% and 81% for FBRwoc, respectively. Due to crystal losses at each junction (17%-31%), the crystal recovery efficiency of FBRwoc was relatively low (47%-65%) for both influent concentrations. However, the losses were minimal in FBRwc, which showed 75% and 92% crystal recovery for low and high phosphorus concentrations, respectively. At low calcium concentration, crystal chemical analysis showed the product to be pure struvite (> 99%). The scanning electron microscope and X-ray diffraction results further confirmed that the crystal recovered from FBRwc contained pure struvite, which could be considered a high quality fertilizer. Except HRT, all parameters (pH, Mg/P, N/P and Ca/Mg) were found to be influencing factors for FBRwc performance. Overall, inserting cones in each part of the reactor played a significant role in enhancing struvite recovery from a wide range of phosphorus-containing wastewater.

Removal and fate of micropollutants in a sponge-based moving bed bioreactor.

This study investigated the removal of micropollutants using polyurethane sponge as attached-growth carrier. Batch experiments demonstrated that micropollutants could adsorb to non-acclimatized sponge cubes to varying extents. Acclimatized sponge showed significantly enhanced removal of some less hydrophobic compounds (log D<2.5), such as ibuprofen, acetaminophen, naproxen, and estriol, as compared with non-acclimatized sponge. The results for bench-scale sponge-based moving bed bioreactor (MBBR) system elucidated compound-specific variation in removal, ranging from 25.9% (carbamazepine) to 96.8% (ß-Estradiol 17-acetate) on average. In the MBBR system, biodegradation served as a major removal pathway for most compounds. However, sorption to sludge phase was also a notable removal mechanism of some persistent micropollutants. Particularly, carbamazepine, ketoprofen and pentachlorophenol were found at high concentrations (7.87, 6.05 and 5.55 µg/g, respectively) on suspended biosolids. As a whole, the effectiveness of MBBR for micropollutant removal was comparable with those of activated sludge processes and MBRs.

Effect of intermittent aeration cycle on nutrient removal and microbial community in a fluidized bed reactor-membrane bioreactor combo system.

Effect of intermittent aeration cycle (IAC=15/45-60/60min) on nutrient removal and microbial community structure was investigated using a novel fluidized bed reactor-membrane bioreactor (FBR-MBR) combo system. FBR alone was found more efficient for removing PO4-P (>85%) than NH4-N (<40%) and chemical oxygen demand (COD<35%). However, in the combo system, COD and NH4-N removals were almost complete (>98%). Efficient nitrification, stable mixed liquor suspended solid and reduced transmembrane pressure was also achieved. Quantitative real-time polymerase chain reaction results of total bacteria 16S rRNA gene copies per mL of mixed-liquor varied from (2.48±0.42)×10(9) initial to (2.74±0.10)×10(8), (6.27±0.16)×10(9) and (9.17±1.78)×10(9) for 15/45, 45/15 and 60/60min of IACs, respectively. The results of clone library analysis revealed that Proteobacteria (59%), Firmicutes (12%) and Bacteroidetes (11%) were the dominant bacterial group in all samples. Overall, the combo system performs optimum nutrient removal and host stable microbial communities at 45/15min of IAC.

Simultaneous removal of phosphorus and nitrogen from sewage using a novel combo system of fluidized bed reactor-membrane bioreactor (FBR-MBR).

A FBR-MBR combo system was designed as a novel approach for simultaneous phosphorus and nitrogen removal from sewage. The combo system was evaluated more than 7 months under variable pH (7.5-9.5), hydraulic retention times (HRT=2-10h), intermittent aeration cycles (IAC) (on/off=60/60-15/45 min) and sludge retention times (SRT=10-60 d). Prior recovery of phosphorus as struvite in the FBR enhanced nitrogen and COD removal efficiency in MBR. Under optimum operating conditions (pH=9, HRT=6h and IAC=45/15 min), PO4(3-)-P, NH4(+)-N and COD removal efficiencies were 92.6 ± 4.2, 98.7 ± 1.2 and 99.3 ± 0.5%, respectively. Stable mixed liquor suspended solid concentration (3.0-5.0 g/L); enhanced nitrification-denitrification activity (78-92%) and reduced transmembrane pressure were also achieved. Compared to soluble microbial products, extracellular polymeric substances (EPS) showed strong correlation with fast membrane fouling. Among EPS components, carbohydrate rather than protein was associated with membrane fouling. Except HRT, all parameters considered (pH, IAC, SRT) showed a significant effect on removal efficiency.

[Influence of community structure of phosphorus removing bacteria under oxygen contain in processes for phosphorus removal].

It was studied for community structure of microorganisms in the phosphorus removal processes under the circulating situation, and analyzed for microorganism's structure and behavior characteristics by the molecular biology technique with direct obtaining of DNA from samples of activated sludge, and by nested PCR and DGGE. It was also determined community structure of microorganisms. It was analyzed structures of Proteobacteria and Acidobacterium by 16S rDNA V3 area gene fragments sequences in activated sludge. By comparing gene sequences in the National Center of Biological Information (NCBI), were determined the kinds of part of microorganisms. Analyzing the low of changes of preponderant bacteria in anaerobic/aerobic and anaerobic/anoxic conditions takes to know, that under the stable situation of phosphorus removing, the system of microorganism's structure can kept mostly constant. Minority races that have changed in amount or kind has something to do with the variation of oxygen level in the system, but structure totally can adapt the environmental conditions of the processes, while it placed in dynamic varieties.

Particle size distribution and removal by a chemical-biological flocculation process.

The particle characterization from the influent and effluent of a chemical-biological flocculation (CBF) process was studied with a laser diffraction device. Water samples from a chemically enhanced primary treatment (CEPT) process and a primary sediment tank process were also analyzed for comparison. The results showed that CBF process was not only effective for both the big size particles and small size particles removal, but also the best particle removal process in the three processes of CBF process, CEPT process, and PST process (primary sediment tanks). The results also indicated that CBF process was superior to CEPT process in the heavy metals removal. The high and non-selective removal for heavy metals might be closely related to its strong ability to eliminate small particles. Samples from different locations in CBF reactors showed that small particles were easier to aggregate into big ones and those disrupted flocs could properly flocculate again along CBF reactor because of the biological flocculation.

[Analysis on mechanism of the chemical-biological flocculation process].

Zeta potential, particle size distribution and molecular weight distribution of dissolved TOC were studied to elementarily disclose the mechanism of the chemical-biological flocculation (CBF) process to treat municipal wastewater. Chemically enhanced primary treatment (CEPT) process and primary sedimentation tank process were taken as the parallel-compared wastewater treatment processes. The experimental results show that under the same dosage, Zeta potential of the CBF process effluent is equal to that of the CEPT process, which indicates that flocculant in return sludge does not change the stabilization of particles in CBF reactor, and the biological flocculation is the key reason for CBF is superior to CEPT. In CBF process, good removal results are achieved for particles >10 microm and dissolved TOC with molecular weight >6 ku by chemical dosage, and biological flocculation can not only promote the removal of particles >10 microm and dissolved TOC with molecular weight >6 ku, but also have high capacity to remove small particles and dissolved TOC with small molecular weight, with the results that particles >3 tpm are removed completely and TOC with molecular weight of 2-6 ku are removed by 42.5% .

Operation of three parallel AN/AO processes to enrich denitrifying phosphorus removing bacteria for low strength wastewater treatment.

Three parallel anaerobic-anoxic/anaerobic-aerobic (AN/AO) processes were developed to enrich denitrifying phosphorus removal bacteria (DPB) for low strength wastewater treatment. The main body of the parallel AN/AO process consists of an AN (anaerobic-anoxic) process and an AO (anaerobic-aerobic) process. In the AO process, the common phosphorus accumulating organisms (PAOs) was dominate, while in the AN process, DPB was dominate. The volume of anaerobic zone(V(ana)):anoxic zone(V(ano)): aerobic zone (V(aer)) for the parallel AN/AO process is 1:1:1 in contrast with a V(ana):V(aer) and V(ano):V(aer) of 1:2 and 1:4 for a traditional biological nutrient removal process (BNR). Process 3 excels in the 3 processes on the basis of COD, TN and TP removal. For 4 month operation, the effluent COD concentration of process 3 did not exceed 60 mg/L; the effluent TN concentration of process 3 was lower than 15 mg/L; and the effluent TP concentration of process 3 was lower than 1 mg/L.

Nitrogen and phosphorus removal under intermittent aeration conditions.

A practice wastewater treatment plant was operated using intermittent aeration activated sludge process to enhance biological nitrogen and phosphorus removal. When the influent concentrations of CODCr, BOD5, TN, TP, NH3-N, TKN, and SS varied in a range of 207.5-1640 mg/L, 61.8-637 mg/L, 28.5-75.6 mg/L, 4.38-20.2 mg/L, 13.6-31.9 mg/L, 28.5-75.6 mg/L, and 111-1208 mg/L, the effluent means were less than 50 mg/L, 20 mg/L, 5 mg/L, 1.0 mg/L, 5 mg/L, 10 mg/L, and 20 mg/L, respectively. Based on a long time of operating results, this process is very suitable for nutrient biological removal for treating the municipal wastewater those water characteristics are similar as that of the Songjiang Municipal Waste Water Treatment Plant(SJMWTP).