Porous polyurethane biocarriers could enhance system nitrification resilience under high organic loading by retaining key functional bacteria.

Resilience to increasing organic loading rates (OLRs) is the key to maintaining stable performance in treating industrial wastewater. First, this study compared the stability, particularly the nitrification performance, of two lab-scale moving bed biofilm reactors (MBBRs) filled with porous polyurethane biocarriers with two conventional activated sludge reactors (ASRs) in the treatment of synthetic coking wastewater under OLRs increasing from 0.3 kg to 1.

Laccase-loaded CaCO sustained-release microspheres modified SBES anode for enhance performance in the remediation of soil contaminated with phenanthrene and pyrene.

This study aimed to enhance the efficiency of SBES in remediating polycyclic aromatic hydrocarbon (PAH)-contaminated soils by modifying the anode with laccase. The experiment involved four SBES anodes: a carbon nanotube-modified anode (CNT), a free laccase-modified anode (Lac), a gelatin-encapsulated laccase-modified anode (Lac-Gel), and a CaCO sustained-release microsphere-loaded laccase-modified (CaCO-SMs@Laccase) anode (Lac-SMs). The CaCO-SMs@Laccase notably extended the active period of laccase, with laccase activity in the Lac-SMs measured at 1.

Adsorption behavior and mechanism of Cu(II) by sodium alginate/carboxymethylcellulose/magnesium hydroxide (SC-MH) hydrogel.

In the present work, an environmentally-friendly, reusable hydrogel ball characterized by its great adsorption capacity to Cu(II) was synthesized. The preparation of this hydrogel drew on sodium alginate (SA) and carboxymethyl cellulose (CMC) as primary composition elements. The endeavor brought novelty by ingeniously infusing it with slurry magnesium hydroxide (MH).

Recovery of ammonia nitrogen from simulated reject water by bipolar membrane electrodialysis.

Ammonia monohydrate (NH·HO) is an important chemical widely used in industrial, agricultural, and pharmaceutical fields. Reject water is used as the raw material in self-built bipolar membrane electrodialysis (BMED) to produce NH·HO. The effects of electrode materials, membrane stack structure, and operating conditions (current density, initial concentrations of the reject water, and initial volume ratio) on the BMED process were investigated, and the economic costs were analyzed.

Rapid start-up of an innovative pilot-scale staged PN/A continuous process for enhanced nitrogen removal from mature landfill leachate via robust NOB elimination and efficient biomass retention.

The start-up and stable operation of partial nitritation-anammox (PN/A) treatment of mature landfill leachate (MLL) still face challenges. This study developed an innovative staged pilot-scale PN/A system to enhance nitrogen removal from MLL. The staged process included a PN unit, an anammox upflow enhanced internal circulation biofilm (UEICB) reactor, and a post-biofilm unit.

Carbon footprint analysis and comprehensive evaluation of municipal wastewater treatment plants under different typical upgrading and reconstruction modes.

The issue of greenhouse gas (GHG) emissions resulting from the upgrading and reconstruction of municipal wastewater treatment plants (MWWTPs) along with improved water quality is receiving attention and research. There is an urgent need to explore the impact of upgrading and reconstruction on carbon footprint (CF) in order to address concerns that the upgrading and reconstruction will increase GHG emissions while improving water quality. Here we accounted for the CF of five MWWTPs in Zhejiang Province, China, before and after three different upgrading and reconstruction models - "Improving quality and efficiency" ("Mode I"), "Upgrading and renovation" ("Mode U") and "Improving quality and efficiency plus Upgrading and renovation" ("Mode I plus U").

Startup and performance of a novel single-stage partial nitritation/anammox system for reject water treatment.

A novel internal circulation contact oxidation membrane bioreactor (ICCOMBR) was constructed to investigate a three steps startup strategy of single-stage partial nitritation-anammox (SPNA) system. A stable nitrite accumulation rate (NAR) of 86.60% was achieved with NH-N over 250 mg/L in nitritation process.

Comparison between thermophilic and mesophilic anaerobic digestion of waste activated sludge by combined NaOH-microwave pretreatment.

The purpose of this study was to investigate the performance of the thermophilic and mesophilic anaerobic digestion process (TADP, MADP) fed with NaOH-microwave pretreated waste activated sludge. The experiment was conducted in anaerobic CSTR reactors. During this experiment, the reactors were stable in operation and were not inhibited by ammonia.

Preparation of composite adsorbents of activated carbon supported MgO/MnO and adsorption of Rhodamine B.

Activated carbon (AC) was modified by MgO and MnO through an impregnation-precipitation-calcination procedure. The batch experiments of adsorption of Rhodamine B (RB) by a modified adsorption material, an MgO-MnO-AC composite, were carried out and the characteristics of the composite adsorbent were evaluated. The results showed that manganese/magnesium loading changed the surface area, pore volume and increased the number of active adsorption sites of AC.

Impact of the acetate/oleic acid ratio on the performance, quorum sensing, and microbial community of sequencing batch reactor system.

This study comprehensively investigated the impact of acetate/oleic acid ratios (80%/20%, 60%/40%, 40%/60%, and 20%/80%) on sequencing batch reactor (SBR) with respect to the variations in performance, quorum sensing (QS), and microbial community. Results showed that NH-N removal was not affected by the acetate/oleic acid ratios, while the COD, total nitrogen (TN), and PO-P removal was considerably affected. The increasing oleic acid ratios led to severe sludge bulking, which was significantly positively correlated with proteins/polysaccharides (p < 0.

Insights into the effects of carbon source on sequencing batch reactors: Performance, quorum sensing and microbial community.

Effects of carbon source on the performance, quorum sensing (QS) and microbial communities in the sequencing batch reactors were investigated in this work. Among the chosen carbon source, sodium acetate (R1), glucose (R2), starch (R3) and Tween 80 (R4), sodium acetate was the best carbon source for nutrient removal, while starch was favorable for inducing the sludge bulking, and Tween 80 was beneficial to the production of extracellular polymeric substances (EPS) and proliferation of Microthrix parvicella. Additionally, the R value of linear correlation between sludge settleability and particle size in four reactors followed an order of R1 > R2 > R3 > R4.

Thermophilic anaerobic digestion reduces ARGs in excess sludge even under high oxytetracycline concentrations.

The feasibility of thermophilic anaerobic digestion (AD) for the attenuation of antibiotic resistance genes (ARGs) in biomass wastes under high antibiotic concentrations remains unclear. In this study, a thermophilic completely stirred digester (55 °C) was fed with municipal excess sludge spiked with increasing concentrations of oxytetracycline (OTC) (0-1000 mg/L) over a period of 280 days. Results showed that thermophilic AD could maintain stable methane production (338.

Effect of kaolin on floc properties for reactive orange removal in continuous coagulation process.

Magnesium hydroxide was used as a coagulant for treating reactive orange wastewater in a real continuous process. Effects of kaolin on coagulation performance and floc properties were investigated with controlled experiments through floc size distribution, zeta potential, scanning electron microscopy and Fourier transform infrared spectroscopy. Kaolin had significant influence on magnesium hydroxide-reactive orange floc formation and growth.

Rapid establishment of thermophilic anaerobic microbial community during the one-step startup of thermophilic anaerobic digestion from a mesophilic digester.

The purpose of this study was to explore how fast the thermophilic anaerobic microbial community could be established during the one-step startup of thermophilic anaerobic digestion from a mesophilic digester. Stable thermophilic anaerobic digestion was achieved within 20 days from a mesophilic digester treating sewage sludge by adopting the one-step startup strategy. The succession of archaeal and bacterial populations over a period of 60 days after the temperature increment was followed by using 454-pyrosequencing and quantitative PCR.

Applying real-time control for achieving nitrogen removal via nitrite in a lab-scale CAST system.

In this study, a bench-scale Cyclic Activated Sludge Technology (CAST) reactor (72?L), fed with domestic sewage, was operated in alternating anoxi-aerobic operation mode to investigate the feasibility of achieving short-cut nitrification and denitrification with a real-time control strategy. An online system for controlling the length of the aeration and stirring phases was implemented, based on pH and oxidation-reduction potential signals, to switch between aerobic and anoxic sequences. Results show that the real-time control strategy was successful in achieving a stable nitrogen removal performance.

Enhancement of thermophilic anaerobic digestion of thickened waste activated sludge by combined microwave and alkaline pretreatment.

Abstract Pretreatment of thickened waste activated sludge (TWAS) by combined microwave and alkaline pretreatment (MAP) was studied to improve thermophilic anaerobic digestion efficiency. Uniform design was applied to determine the combination of target temperature (11 degrees-210 degrees C), microwave holding time (1-51 min), and NaOH dose (0-2.5 g NaOH/g suspended solids (SS)) in terms of their effect on volatile suspended solids (VSS) solubilization.