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Anaerobic membrane bioreactors (AnMBRs) are formed through the combination of anaerobic digestion and membrane technology. The upgraded technology separates SRT from HRT in the anaerobic digester, shortening the treatment period, reducing the digester's volume and improving effluent quality. Furthermore, AnMBRs have a strong tolerance for the existing forms of objects and can handle liquids, high-solid materials and gases. Up to now, AnMBRs have been utilized in the treatment of various types of industrial and municipal wastewater, organic solid waste and also biogas upgrading, and they have achieved excellent performance. However, there are few studies which have discussed their multiple utilization, especially following the flow of wastewater treatment. This study summarizes the application of AnMBRs in their diverse roles in the municipal wastewater treatment process. The discussion revolves around energy generation and the fouling issue of AnMBRs in the treatment of municipal wastewater, the digestion of sewage sludge generated in conventional municipal wastewater treatment and the upgrading of biogas after anaerobic digestion. In addition to controlling operating parameters, strategies used to improve the treatment effectiveness are also introduced. Lastly, online methods for preventing membrane fouling, which is the main operational obstacle to AnMBRs' wider spread, are also discussed. This review aims to provide a fresh perspective on how AnMBRs are utilized in waste treatment. [ABSTRACT FROM AUTHOR]

A novel single-stage partial nitritation–anammox process equipped with porous functional suspended carriers was developed at 25 °C in a CSTR by controlling dissolved oxygen <0.3 mg/L. The nitrogen removal performance was almost unchanged over a nitrogen loading rate ranging from 0.5 to 2.5 kg NH 4 + -N/m 3 /d with a high nitrogen removal efficiency of 81.1%. The specific activity of AOB and anammox bacteria was of 3.00 g-N/g-MLVSS/d (the suspended sludge), 3.56 g-N/g-MLVSS/d (the biofilm sludge), respectively. The results of pyrosequencing revealed that Nitrosomonas (5.66%) and Candidatus_Kuenenia (4.95%) were symbiotic in carriers while Nitrosomonas (40.70%) was predominant in the suspended flocs. Besides, two specific types of heterotrophic filamentous bacteria in the suspended flocs ( Haliscomenobacter ) and the functional carrier biofilm ( Longilinea ) were shown to confer structural integrity to the aggregates. The novel single-stage partial nitritation–anammox process equipped with functional suspended carriers was shown to have good potential for the nitrogen-rich wastewater treatment. [ABSTRACT FROM AUTHOR]

In CO 2 geological storage, the interfacial tension (IFT) between supercritical CO 2 and brine is critical for the storage capacitance design to prevent CO 2 leakage. IFT relies not only on the interfacial molecule properties but also on the environmental conditions at different storage sites. In this paper, supercritical CO 2 -NaCl solution systems are modeled at 343-373 K and 6-35 MPa under the salinity of 1.89 mol/L using molecular dynamics simulations. After computing and comparing the molecular density profile across the interface, the atomic radial distribution function, the molecular orientation distribution, the molecular Gibbs surface excess (derived from the molecular density profile), and the CO 2 -hydrate number density under the above environmental conditions, we confirm that only the molecular Gibbs surface excess of CO 2 molecules and the CO 2 -hydrate number density correlate strongly with the temperature- and pressure-dependent IFTs. We also compute the populations of two distinct CO 2 -hydrate structures (T-type and H-type) and attribute the observed dependence of IFTs to the dominance of the more stable, surfactant-like T-type CO 2 -hydrates at the interface. On the basis of these new molecular mechanisms behind IFT variations, this study could guide the rational design of suitable injecting environmental pressure and temperature conditions. We believe that the above two molecular-level metrics (Gibbs surface excess and hydrate number density) are of great fundamental importance for understanding the supercritical CO 2 -water interface and engineering applications in geological CO 2 storage.