Sulfide Removal Research Articles

Controlling filamentous sludge bulking by regulating oxygen supply in the start of BISURE system

BISURE (BIological SUlfide REmoval) systems are efficient biological systems for sulfide removal and elemental sulfur recovery. However, they often suffer from disturbance caused by filamentous sludge bulking during startup, which are inoculated with activated sludge. In this study, BISURE startup by increasing the influent substrate concentration (IC-mode) and speeding up the influent flow rate (IF-mode) were investigated to understand and avoid the disturbance. The results showed that the BISURE system could be successfully started up in both the IC mode and IF mode, but both modes could trigger filamentous sludge bulking by Thiothrix (a filamentous sulfur-oxidizing bacteria, F-SOB). “CSO going first, PSO following up” was an effective approach to control the filamentous sludge bulking during startup. The procedure mechanism of oxygen effect was revealed: the growth of zoogloeal SOB (Z-SOB) with its larger surface-to-volume ratio (SVR) was first promoted to achieve a “proportion advantage” over F-SOB in the bacterial community; the external location of Z-SOB was then fixed to achieve the “location advantage” over F-SOB in the sludge floc; finally, prior uptake of DO by Z-SOB was ensured to achieve a “sequence advantage” over F-SOB in the substrate utilization. After elimination of filamentous sludge bulking, the dominant SOB in the bacterial community in IC-mode were Thiobacillus, accounting for more than 90% of the population; while dominant SOB in IF-mode were Thiobacillus and Annwoodia, which together accounted for more than 60% of bacteria. These findings are helpful in characterizing biological desulfurization and going forward, should be important in further developing BISURE systems.

Fuzzy optimization design of multicomponent refinery hydrogen network

Hydrogen and light hydrocarbon components are essential resources of the refinery. The optimization of the refinery hydrogen system and recovery of the light hydrocarbon components contained in the gas streams are key strategies to reduce the operating costs for sustainable development. Many research efforts have been focused on the optimization of single impurity hydrogen network, and the flowrates of the hydrogen sources and sinks are assumed to be constant. However, their flowrates vary along with the quality of crude oil and refinery processing plans. A general superstructure of multicomponent refinery hydrogen network is proposed, which considers four components, namely H 2 , H 2 S, CH 4 and C 2 + , as well as the flowrate variations of hydrogen source and hydrogen sink. The mathematical model based on the superstructure is developed with objective functions, including the minimization of total annualized cost and the maximization of overall satisfaction of the hydrogen network. Moreover, the model considers the removal of hydrogen sulfide and the recovery of light hydrocarbon components ( i . e ., C 2 + ) in the optimization. To verify the applicability of the proposed mathematical model, a simplified industrial case study with four scenarios is solved. The optimization results show that the economic benefit can be maximized by considering both the direct reuse of gas streams from high-pressure separator (HP gas stream) and from low-pressure separator (LP gas stream) and the recovery of the light hydrocarbon streams. The fuzzy optimization method can be used to guide the optimal design of the refinery hydrogen system with multi-period variable flowrates.

Coupling oxidation of acid volatile sulfide, ferrous iron, and ammonia nitrogen from black-odorous sediment via autotrophic denitrification-anammox by nitrate addition

The coupling removal of acid volatile sulfide (AVS), ferrous iron, and ammonia nitrogen has been applied for black-odorous sediment remediation. In this study, calcium nitrate with different N/(S + Fe) ratios (0.45, 0.90, 1.20 and 1.80) was added into black-odorous sediment in four systems named R1, R2, R3, and R4. Results showed that the removal rate of AVS was 76.40% in the R1, which was lower compared with rates in R2–R4 around 96.70%. The ferrous oxidation rate was approximately 87.00% in R2–R4, which was considerably higher than that in the R1 (24.62%). And the ammonia was reduced by 81.02%, 88.00%, 100%, and 57.18% in R1, R2, R3 and R4, respectively. During the reaction, nitrite accumulation was observed, indicating partial denitrification. Moreover, microbes related to autotrophic denitrification (e.g., genus Thiobacillus, Dok59, GOUTA19, Gallionella, with the highest abundance of 15.40%, 13.21%, 8.79%, 9.44%, respectively) were detected in all systems. Furthermore, the anammox bacteria Candidatus_Brocadia with the highest abundance of 3.44% and 4.00% in R2 and R3, respectively was also found. These findings confirmed that AVS, ferrous iron, and ammonia nitrogen could be simultaneously removed via autotrophic denitrification coupled with anammox in black-odorous sediment by nitrate addition.

Sulphide Removal from Water Through Electrocoagulation: Kinetics, Equilibrium and Thermodynamic Analysis

Sulphide Removal from Water Through Electrocoagulation: Kinetics, Equilibrium and Thermodynamic Analysis

ПЕРСПЕКТИВА ИСПОЛЬЗОВАНИЯ МЕТИЛДИЭТАНОЛАМИНА НА БЛОКЕ ОЧИСТКИ ТЕХНОЛОГИЧЕСКИХ ГАЗОВЫХ ПОТОКОВ УСТАНОВКИ ГИДРООЧИСТКИ ДИЗЕЛЬНОГО ТОПЛИВА АО «АНХК» ДЛЯ УДАЛЕНИЯ СЕРОВОДОРОДА

It was considered the possibility of using methyldiethanolamine solution instead of
 monoethanolamine solution for hydrogen sulfide removal from process gases in diesel fuel 
 hydrocleaning unit JSC «ANHK». It is demonstrated some advantages and disadvantages 
 methyldiethanolamine-based circulating absorbent in comparison of monoethanolamine-based absor bent.

Surrogate-assisted optimization of refinery hydrogen networks with hydrogen sulfide removal

Hydrogen management is very important for the production of clean fuels such as low-sulfur gasoline and diesel. As a key contaminant in the hydrogen network, hydrogen sulfide not only deactivates catalysts but also corrodes equipments. Hence, it is necessary to integrate hydrogen sulfide removal process model into the optimization of hydrogen allocation network. However, a desulfurization process model with simplifications and assumptions may yield suboptimal results and a model based on rigorous process mechanism may require high computational cost. To solve this problem, this paper proposes a novel approach for simultaneous optimization of refinery hydrogen allocation network and hydrogen sulfide removal processes. The optimization is realized in two steps. First, surrogate models are developed as approximations to the rigorous process and thermodynamic model for the desulfurization processes. Second, the surrogate model is embedded into the mathematical programming model for hydrogen network optimization. The effectiveness of the proposed approach is illustrated by its application to a case study taken from a real refinery. Result comparison between the proposed method and a literature model based on simplified desulfurization models is carried out, proving that, with the proposed method, more practical optimization result can be obtained with much less computational effort.

Targeting Ni-Cu mineralization in the Canadian High Arctic large igneous province: integrating geochemistry, magmatic architecture and structure

Mafic-ultramafic subvolcanic intrusive complexes, at the 1–10-km scale, constitute favorable environments for the formation of orthomagmatic Ni-Cu-PGE sulfide deposits. Within 100–1000-km scale large igneous provinces (LIPs), the most favorable economic target areas may be difficult to identify using a traditional regional exploration approach. We report results of field and laboratory studies focused on an integrated geochemical-architectural model for the Ni-Cu-PGE sulfide potential of the High Arctic large igneous province (HALIP) of Canada, the largest and best-exposed portion of this circum-arctic LIP. Previous lithogeochemical studies of the Canadian HALIP (130–80 Ma) concluded that subalkaline mafic units located on Axel Heiberg Island were more prospective than younger, alkalic igneous rocks (alkaline basalts to basanites) exposed on northern Ellesmere Island. Mapping carried out for this study revealed the presence of abundant subalkaline igneous rocks on western Ellesmere Island. We interpret these units as an extension of the Schei Sills, a stratigraphically bound sequence of intrusions exposed along a ~ N-S belt on eastern Axel Heiberg Island. Samples from the Schei Sills and from the Middle Fiord Intrusive Complex (~ 20 km2, central Axel Heiberg Island) show Cu/Zr values above and below unity, consistent with complementary sulfide enrichment and removal, respectively, within these intrusive systems. The spatial association of the Schei Sills with the post-emplacement Eocene Stolz Thrust is noteworthy, as later thrusting associated with the Paleogene Eurekan Orogeny caused the uplift of deeper parts of the HALIP subvolcanic feeder system and associated wall-rock stratigraphy. Absolute Ir-group PGE contents are low throughout the HALIP; however, Pt-group PGE contents range widely among analyzed tholeiitic intrusive rocks. For example, relatively elevated Pt + Pd values of 10–30 ppb in samples from the Middle Fiord Intrusive Complex and the Schei Sills suggest heightened prospectivity in these two areas. In contrast, tholeiitic flood basalts in the Strand Fiord Formation and associated intrusions exposed in western Axel Heiberg Island (~ 95 Ma) exhibit Cu/Zr < 1 and low Pt + Pd contents (below 10 ppb). The ca. 120 Ma magmatic event associated with the Schei Sills and Middle Fiord Intrusive Complex appears to have generated magmas that are more prospective than those of the younger (ca. 95 Ma) magmatic pulse associated with the flood basalts of the Strand Fiord Formation. This work demonstrates that not all architectural elements of a LIP are equal in terms of metallogenic potential, and that nested zones of higher prospectivity can be identified through the integration of several geological constraints.

Synergistic biological removal of nitrogen and sulfide from saline mariculture wastewater by halophilic consortia

Halophilic marine anammox bacteria (MAB)-based sulfide-based autotrophic denitratation and anammox (MSADA) process was investigated to treat seawater-based wastewater under different influent sulfide to nitrate (S/N) ratios. This study firstly presented a novel method with merely inoculating halophilic MAB-based sludge to start up the MSADA process in a sequencing batch reactor. Nitrogen and sulfide could be efficiently removed from seawater-based wastewater at the total nitrogen removal efficiency of 93.7% and sulfide removal efficiency of 100% under the optimum S/N ratio of 0.75 in the MSADA process. Meanwhile, anammox and sulfide-based autotrophic denitrification respectively accounted for about 94.2% and 5.8% of the total nitrogen removal with the high nitrite accumulation efficiency of 92.7%. At the optimum S/N ratio of 0.75, “Candidatus Scalindua” (3.28%), Sulfurimonas (18.68%) and Sulfurovum (11.04%) were the main functional microorganisms, which had the excellent salt tolerance. The dominating functional microorganisms dynamically changed with the different S/N ratios. The microbial community composition was similar and steady when the S/N ratios were 0.33–0.75. Nitrate reductase activity was much higher than nitrite reductase activity in the MSADA system, which made it possible to keep the NO3−-N reduction products at NO2−-N level and provide sufficient NO2−-N for MAB. The coupled process provides a new perspective in the treatment of seawater-based wastewater.

Hierarchical porous HKUST-1 fabricated by microwave-assisted synthesis with CTAB for enhanced adsorptive removal of benzothiophene from fuel

• Hierarchical porous defective HKUST-1 rapidly obtained by microwave-assisted method. • Enhanced benzothiophene removal from fuel by defective HKUST-1 over HKUST-1. • Defective HKUST-1 exposes more active sites and facilitates adsorbates diffusion. • CTAB-H-0.5 shows excellent adsorption and regeneration performance for BT removal. Ultra-deep removal of thiophene sulfides from transportation fuel via adsorption has aroused great attention under the pressure of gradually demanding environmental regulations. The development of high-efficiency adsorbents is the key to adsorptive desulfurization for producing clean transportation fuels. In this work, a microwave-assisted synthesis method was applied to rapidly fabricate hierarchical porous defective HKUST-1 (DEHKUST-1) towards removing benzothiophene from model fuel by selective adsorption. The effects of cetyltrimethylammonium bromide (CTAB) dosage, adsorption temperature and adsorption contact time on the DEHKUST-1 desulfurization performance were systematically investigated. The characterization results proved that both metal clusters and linker defects were generated in the as-prepared DEHKUST-1. CTAB as template could modulate the pore distribution and introduce reasonable defects in the framework of HKUST-1. At CTAB: Cu 2+ = 0.5 by mole ratio, a regular mesoporous distribution of 25–30 nm could be obtained with DEHKUST-1; it exhibited an impressive enhancement in adsorptive desulphurization performance. The maximum adsorption capacity of the adsorbent attained 14.4 mg S/g adsorbent at 20 °C in 4 h. Even after CTAB-H-0.5 was regenerated six times, its adsorption capacity remained 93% as that of the as-prepared adsorbent. An adsorption mechanism was proposed to illustrate the promoting desulfurization performance by introduction of hierarchical porous in HKUST-1. By virtue of the rapid synthesis and remarkable benzothiophene removal capacity, the DEHKUST-1 could be a potential adsorbent in desulfurization from real fuels.

Physicochemical Characteristics of Activated Carbon Impregnated with Different Type of Metal Oxide Nanoparticles towards Hydrogen Sulfide Removal

It is highly anticipated to understand the influence of physicochemical characteristics of different types metal oxide nanoparticles impregnated onto palm shell activated carbon (PSAC) adsorbent towards hydrogen sulfide (H 2S) removal. Alkaline precipitation method was used to synthesis metal oxide nanoparticles (CeO 2, NiO, CuO, and Fe 2O 3). The synthesised metal oxide nanoparticles were then impregnated in the pre-oxidized PSAC adsorbents (Ce/PSAC, Ni/PSAC, Cu/PSAC and Fe/PSAC). The prepared adsorbent was then analysed via Scanning Electron Microscope – Energy Dispersive X-ray (SEM-EDX), Thermogravimetric analysis (TGA), Fourier-transform infrared spectroscopy (FTIR) and H 2S adsorption analysis. Based on H 2S adsorption study, different types of metal oxide nanoparticles impregnated on PSAC adsorbent showed different trend of breakthrough time and adsorption capacity. PSAC adsorbent that was modified with metals oxide nanoparticles shows efficient result compared to raw PSAC adsorbent. Among metal oxide nanoparticles, Cu/PSAC adsorbent gives the higher adsorption capacity (86.60 mg H 2S/g Cu/PSAC) and breakthrough time (80 minutes) compared to the rest of adsorbents.

Preparation of Potassium Permanganate Confined in Porous Carbon Synthesized from Palm Kernel Shell and its Application for Hydrogen Sulfide Removal

The goal of this study is to investigate the efficacy of potassium permanganate (KMnO4) confined in porous carbon for hydrogen sulfide removal. As porous support, carbon was prepared by carbonization process of abundantly biomass source of palm kernel shell (named KATKS). The surface of porous carbon was first modified using hydrogen peroxide oxidation. The confinement process was carried out by an impregnation process. The KMnO4 contents in porous carbon were varied i.e. 5%, 10%, and 20% w/w (KMnO4-%/KATKS-Ox). Materials were characterized by N2-sorption analysis and SEM-EDX. The results showed that KATKS possesses a high specific surface area of ca. 700 m2/g. Due to the impregnation of KMnO4, the specific surface area of KMnO4-%/KATKS-Ox decreased to ca. 450 m2/g. SEM-EDX revealed a successful confinement process in which elements of K, Mn, and O were displayed and dispersed on the carbon surface. In the hydrogen sulfide (H2S) oxidation testing, KMnO4-20%/KATKS-Ox showed the highest performance of H2S removal compared to other materials due to the high amount of KMnO4. KMnO4-20%/KATKS-Ox could reduce until 98.7% of H2S. This is remarkably higher than only using bulk KMnO4 (without confinement) which showed activity of ca. 70% reduction.

A Retrospection of Hydrogen Sulphide Removal Technologies in Biogas Purification

A Retrospection of Hydrogen Sulphide Removal Technologies in Biogas Purification

Effective removal of hydrogen sulfide using Mn-based recovered oxides from recycled batteries

The use of clean and environmentally friendly renewable energy as well as the minimization of waste disposal are fundamental aspects to be considered nowadays in a circular economy approach. In this way, the development of efficient systems for sulfur removal in biomass and waste gasification is of key relevance and the use of recycled materials will provide an opportunity to combine the reduction of waste‘s production and the application of circular economy principles.Sorbents from waste powder of recycled batteries have been prepared at laboratory scale. Subsequently, their potential application to syngas cleaning is evaluated specifically for H2S removal. Lab-scale tests at 400°C, 10 bar and space velocity of 3500 h−1 were carried out using first a simplified gas mixture of 0.9% H2S in N2 and then a more complex one consisting of 20% H2, 40% CO and 0.45% H2S/N2 to investigate the effect of reducing components, CO and H2 co-existing with H2S in any syngas. Sorbent utilization values as high as 80% (w/w, %) were obtained when tested under realistic syngas composition. XRF, XRD, XPS, TEM and textural characterization results of fresh and sulfided samples showed that those materials with higher Mn contents showed higher H2S removal capacity although the Mn/Zn ratio demonstrated to play a crucial role in their selectivity to form sulfides. Additionally, plausible mechanisms for H2S removal are discussed where the influence of composition, structure and morphology of the recovered binary metal oxides on sulfur removal efficiency is analysed.

Recovery of gold from refractory gold ores: Effect of pyrite on the stability of the thiourea leaching system

The extraction of gold from refractory gold ores (RGOs) without side reactions is an extremely promising endeavor. However, most RGOs contain large amounts of sulfide, such as pyrite. Thus, investigation of the influence of sulfide on the gold leaching process is important to maximize the utilization of RGOs. In this work, the effects of pyrite on the stability of the thiourea system were systematically investigated under different conditions. Results showed that the decomposition rate of thiourea was accelerated sharply in the presence of pyrite. The effect of pyrite on gold recovery in thiourea leaching systems was then confirmed via a series of experiments. The decomposition efficiency of thiourea decreased by 40% and the recovery efficiency of gold increased by 56% after the removal of sulfide by roasting. Under optimal conditions, the efficiency of the gold recovery system increased to 83.69% and only 57.92% of thiourea decomposition was observed. The high consumption of thiourea by the leaching system may be attributed to not only adsorption by mineral particles but also catalytic decomposition by some impurities in the ores, such as pyrite and soluble ferric oxide.

Validation of effective role of substrate concentrations on elemental sulfur generation in simultaneous sulfide and nitrate removal process

Simultaneous nitrogen and sulfur removal process has broad application prospects, which can accomplish simultaneous sulfide and nitrate removal to recover elemental sulfur from wastewater. The effective role of substrate concentrations in elemental sulfur generation was investigated through substrate removal, product conversion, characteristics and distribution of elemental sulfur along microbial community structure. Furthermore, a multivariate linear fitting equation was used to simulate the contribution of substrate concentration on elemental sulfur generation. Based on the statistical analysis (Multiple comparisons, Pearson correlation analysis and Principal Component Analysis), it was confirmed that substrate concentration elevation exerted a significant positive effect on the generation of elemental sulfur regardless of its presence in either effluent or sludge (p < 0.05). The results showed that bulk of the produced elemental sulfur mainly existed in the effluent of the reactor (76.59–88.28% of total elemental sulfur), rather than in the sludge (11.72–23.41% of total elemental sulfur). Zeta potential of elemental sulfur in the effluent was in the range of −15.70 mV to −18.92 mV. Sulfurovum was the dominant genus enriched by high substrate concentration whose relative abundance was higher than 79.46%.

Model Parameters for Aerobic Biological Sulfide Oxidation in Sewer Wastewater

Sulfide related odor and corrosion are two of the major problems associated with the operation and maintenance of sewer networks. The extent of the problems is governed by several complex and interrelated processes. Sulfide oxidation is typically the most important process for sulfide removal in wastewater from aerobic gravity sewers. Despite the significance of the process, little is known about the significance of the growth of sulfide oxidizing bacteria (SOB) during the transport of wastewater. Biological sulfide oxidation in wastewater from sewers was investigated in a series of oxygen uptake rate (OUR) experiments. The experiments showed that, for oxygen nonlimiting conditions, sulfate was produced, with elemental sulfur as an intermediate. During each experiment, the activity of the sulfide oxidizing bacteria increased significantly. This was interpreted as the result of bacterial growth related to the oxidation of intermediately stored elemental sulfur. A model concept describing biological sulfide oxidation, with intermediary storage of elemental sulfur and associated growth, was developed. The model was calibrated against the experimental results. The observed average growth rate and yield constant for the SOB were determined at 1.98 d−1 and 0.17 g Chemical Oxygen Demand (COD) per g sulfur, respectively. These values correspond to reported values for mixed cultures of autotrophic SOB.

Deep desulfurization performance of thiophene with deep eutectic solvents loaded carbon nanotube composites.

One source of air pollution is the combustion of sulfur compounds in fuel oil. Reducing sulfur content in fuel oil has become a hot issue demanding timely solutions. Using ionic liquids and deep eutectic solvents (DESs) to remove sulfides in fuel oil has achieved good results presently. However, since DESs are liquid and their transportation and separation are inconvenient, a new way is proposed that the DESs are loaded on the carbon nanotubes (CNTs) with large specific surface area and good chemical stability. A series of composites materials (DESs/CNTs) were prepared. Finally, they are applied to the removal of sulfides in fuel oil. This loading method, which imparts introduced unique physico-chemical properties of the DESs to the carrier materials, preserves both advantages while overcoming some of the problems with DESs. The interaction between DESs and CNTs is mutual promotion. Therefore, this study has important theoretical significance and industrial application value. Under optimal conditions, when the reagent ChCl/p-TsOH (1 : 2) was loaded on multi-walled CNTs (OD = 30–60 nm) to prepare the composite material (ChCl/p-TsOH)/CNTs, the single desulfurization rate of the composite material was 95.8%. Finally, the catalytic/oxidation mechanism was studied systematically and this work would provide a green route for the desulfurization of fuels.

Hydrogen sulfide removal technology: A focused review on adsorption and catalytic oxidation

The principal technologies for H2S removal are reviewed herein. Two technologies in particular, adsorption and catalytic oxidation, are considered as promising for desulfurization in terms of process simplicity, H2S removal performance, and operational cost. Nanoporous materials such as activated carbons, zeolites, mesoporous silicas, and metal organic frameworks are extensively used as sorbents because their porous characteristics are suitable for efficient diffusion and capture of H2S. To improve the H2S adsorption performance, these materials are frequently modified with functional groups or doped with various metal oxides. For example, representative metal oxide-based catalysts (e.g., vanadium, magnesium, and iron oxides) have been investigated for the selective oxidation of H2S to elemental sulfur. In this context, the dispersion of active metals onto supports, or the addition of modifying metals, are reasonable strategies for inhibiting catalyst deactivation and enhancing catalytic activity. Emerging studies based on the combination of adsorption and catalytic oxidation have introduced the syntheses of dual-function materials, such as metal nanoparticle-dispersed or metal-free porous carbons. In conclusion, comprehensive research into catalyst synthesis and performance evaluation must continue in order to develop the most promising technology for H2S removal.

Simultaneous hydrogen sulfide removal and wastewater purification in a novel alum sludge-based odor-gas aerated biofilter

A novel alum sludge-based odor-gas aerated vertical flow biofilter (Al-OAF) was developed, which aims to removal the pollutants in wastewater and simultaneously to eliminate H2S generated from wastewater treatment facility. Three lab-scale parallel columns were operated in batch model while intermittently aerated with 200 ppm H2S (Al-OAF), air (Al-AF) and unaerated (Al-F, as blank), respectively. The pollutants in wastewater and the effluent H2S concentration from Al-OAF were monitored regularly. Results showed that three columns presented a high removal efficiency (>98%) of total phosphorus (TP) and a completed removal of H2S (100%) in Al-OAF. Al-OAF and Al-AF could enhance the removal efficiency of chemical oxygen demand (COD) of 94.3 ± 3.0, 94.8 ± 1.9%, and total nitrogen (TN) of 86.2 ± 14.2, 91.6 ± 5.4%, respectively. In particular, there was no significant difference regarding the COD, TN removal performances between the “H2S driven” Al-OAF and the “air driven” Al-AF. The H2S removal mechanism lies in the alum sludge ability of H2S adsorption and the reaction by the biofilm in the biofilter. This demonstrates that the novel Al-OAF (aerated with waste gas) would be a promising “wise choice” for intensified biofilter with dual-goals of simultaneous wastewater purification and H2S elimination.

Realization of nitrite accumulation in a sulfide-driven autotrophic denitrification process: Simultaneous nitrate and sulfur removal

The study was based on the removal of nitrate and sulfide, and aimed to nitrite accumulation. The process of autotrophic denitrification driven by sulfide as an electron donor was investigated in a sequencing batch reactor. The research showed that autotrophic denitrification successfully started on day 22, and the removal rates of NO3−-N and S2--S were 95.8% and 100%, respectively, when the S/N molar ratio was 1.45. When the S/N ratio was reduced to 0.94, the phenomenon of NO2−-N accumulation was observed. NO2−-N continuously accumulated, and the maximum accumulation rate was 55.3% when the S/N ratio was 0.8. In the batch test, the study showed that NO2−-N accumulation was optimal when the S/N ratio was 0.8, and the NO2−-N concentration increased with increasing NO3−-N concentration at the same S/N ratio. Microbial communities also changed based on the high-throughput analysis, and Proteobacteria (59.5%–84%) was the main phylum. Arenimonas (11.4%–28.2%) and uncultured_f_ Chromatiaceae (5.7%–27.5%) were the dominant bacteria, which complete denitrification and desulfurization throughout the operating system. Therefore, this study provided a theoretical basis for the simultaneous removal of NO3−-N and S2--S, as well as the accumulation of nitrite, and provided material support for anaerobic ammonia oxidation technology.