Overcoming deep-dewatering challenges in food waste digestate with polyethylene oxide as an innovative conditioning agent.

The effective treatment of food waste digestate is critical for reducing environmental pollution and mitigating carbon emissions, with deep dewatering playing a pivotal role. Conventional dewatering agents such as polyaluminum chloride (PAC) and polyacrylamide (PAM), commonly employed in municipal sludge treatment, exhibit limited efficacy when applied to food waste digestate due to the latter's high salinity and advanced fermentation stages. This study introduces polyethylene oxide (PEO) as a novel conditioning agent and investigates its dewatering performance in comparison to PAC and PAM, elucidating the underlying mechanism.

Flow-electrode capacitive separation of organic acid products and recovery of alkali cations after acidic CO electrolysis.

Acidic CO electrolysis, enhanced by the introduction of alkali cations, presents a strategic approach for improving carbon efficiency compared to processes conducted in neutral and alkaline environments. However, a significant challenge arises from the dissolution of both organic acids and alkali cations in a strongly acidic feed stream, resulting in a considerable energy penalty for downstream separation. In this study, we investigate the feasibility of using flow-electrode capacitive deionization (FCDI) technology to separate organic acids and recover alkali cations from a strongly acidic feed stream (pH ~ 1).

Comprehensive analysis of the relationship between yield stress and dewatering performance in sludge conditioning: Insights from various treatment methods.

Understanding the relationship between sludge yield stress (σ) and dewatering performance is essential for optimizing sludge conditioning processes. This study systematically investigates the effects of various conditioning methods-including thermal hydrolysis (TH), freezing/thawing (FT), anaerobic digestion (AD), polyaluminum chloride (PAC), polyacrylamide (PAM), and Fenton treatment (Fenton)-on sludge yield stress and its correlation with dewatering efficiency. Using linear regression, partial least squares regression (PLSR), and correlation heatmap analyses, we reveal significant variations in the correlation between σ and dewatering indexes, including moisture content (Mc), capillary suction time (CST), and bound water proportion (Wb/Wt), depending on the conditioning method and intensity.

Solid Electrolytes for Low-Temperature Carbon Dioxide Valorization: A Review.

One of the most promising approaches to address the global challenge of climate change is electrochemical carbon capture and utilization. Solid electrolytes can play a crucial role in establishing a chemical-free pathway for the electrochemical capture of CO. Furthermore, they can be applied in electrocatalytic CO reduction reactions (CORR) to increase carbon utilization, produce high-purity liquid chemicals, and advance hybrid electro-biosystems.

A novel approach for sludge deep-dewatering via flowing-out enhancement but not relying on cell lysis and bound water release.

Effective deep-dewatering is crucial for wastewater sludge management. Currently, the dominant methods focus on promoting cell lysis to release intracellular water, but these techniques often lead to secondary pollution and require stringent conditions, limiting their practical use. This study explores an innovative method using a commercially available complex quaternary ammonium salt surfactant, known as G-agent.

Delineating cathodic extracellular electron transfer pathways in microbial electrosynthesis: Modulation of polarized potential and Pt@C addition.

Microbial electrosynthesis (MES) is an innovative technology that employs microbes to synthesize chemicals by reducing CO. A comprehensive understanding of cathodic extracellular electron transfer (CEET) is essential for the advancement of this technology. This study explores the impact of different cathodic potentials on CEET and its response to introduction of hydrogen evolution materials (Pt@C).

Ferrihydrite-mediated methanotrophic nitrogen fixation in paddy soil under hypoxia.

Biological nitrogen fixation (BNF) by methanotrophic bacteria has been shown to play an important role in maintaining fertility. However, this process is still limited to aerobic methane oxidation with sufficient oxygen. It has remained unknown whether and how methanotrophic BNF proceeds in hypoxic environments.

Yield stress Measurement of municipal sludge: A comprehensive evaluation of testing methods and concentration effects using a rotational rheometer.

Accurate prediction and measurement of yield stress are crucial for optimizing sludge treatment and disposal. However, the differences and applicability of various methods for measuring yield stress are subjects of ongoing debate. Meanwhile, literature on measuring sludge yield stress is limited to low solid concentrations (TS <10%), understanding and studying the yield stress of medium to high solid concentration sludge is crucial due to increasingly stringent standards for sludge treatment and disposal.

Surface coating combined with in situ cyclic voltammetry to enhance the stability of gas diffusion electrodes for electrochemical CO reduction.

Electrochemical CO reduction (CORR), fueled by clean and renewable energy, presents a promising method for utilizing CO effectively. The electrocatalytic reduction of CO to CO using a gas diffusion electrode (GDE) has shown great potential for industrial applications due to its high reaction rate and selectivity. However, guaranteeing its long-term stability still poses a significant challenge.

Refining microbial potentiometric sensor performance with unique cathodic catalytic properties for targeted application scenarios.

Traditional microbial electrochemical sensors encounter challenges due to their inherent complexity. In response to these challenges, the microbial potentiometric sensor (MPS) technology was introduced, featuring a straightforward high-impedance measurement circuit tailored for environmental monitoring. Nonetheless, the practical implementation of conventional MPS is constrained by issues such as the exposure of the reference electrode to the monitored water and the absence of methodologies to stimulate microbial metabolism.

Super-fast Charging Biohybrid Batteries through a Power-to-formate-to-bioelectricity Process by Combining Microbial Electrochemistry and CO Electrolysis.

Extensive study on renewable energy storage has been sparked by the growing worries regarding global warming. In this study, incorporating the latest advancements in microbial electrochemistry and electrochemical CO reduction, a super-fast charging biohybrid battery was introduced by using pure formic acid as an energy carrier. CO electrolyser with a slim-catholyte layer and a solid electrolyte layer was built, which made it possible to use affordable anion exchange membranes and electrocatalysts that are readily accessible.

Enhancing data reliability in quantitative characterization of moisture distribution in sludge using DSC: Impact of sample attributes and test parameters.

Exploring moisture distribution, especially bound water content, is vital for studying and applying sludge dewatering. The differential scanning calorimetry (DSC) method has been extensively utilized for the quantitative characterization of moisture distribution in sludge. However, this method has certain limitations, such as low reproducibility of results, leading to controversial parameter values in different papers and hindering result comparison.

Enrichment of biofertilizer-type hydrogen-oxidizing bacteria on urea containing Cu(II).

With the utilization of pesticides and fertilizers (e.g. urea), the presence of nitrogen and heavy metals (e.

Novel Insight into Microbially Mediated Nitrate-Reducing Fe(II) Oxidation by sp. Strain BoFeN1 Using Dual N-O Isotope Fractionation.

Microbially mediated nitrate reduction coupled with Fe(II) oxidation (NRFO) plays an important role in the Fe/N interactions in pH-neutral anoxic environments. However, the relative contributions of the chemical and microbial processes to NRFO are still unclear. In this study, N-O isotope fractionation during NRFO was investigated.

Sunlight Significantly Enhances Soil Denitrification via an Interfacial Biophotoelectrochemical Pathway.

Denitrification is an essential step of the nitrogen cycle in soil. However, although sunlight is an important environmental factor for soil, the investigation of the influence of sunlight on soil denitrification is limited to plant photosynthesis-mediated processes. Herein, a new pathway, denoted as a biophotoelectrochemical process, which is induced by the direct photoexcitation of soil, was found to greatly enhance soil denitrification.

Electricity-Driven Microbial Metabolism of Carbon and Nitrogen: A Waste-to-Resource Solution.

Electricity-driven microbial metabolism relies on the extracellular electron transfer (EET) process between microbes and electrodes and provides promise for resource recovery from wastewater and industrial discharges. Over the past decades, tremendous efforts have been dedicated to designing electrocatalysts and microbes, as well as hybrid systems to push this approach toward industrial adoption. This paper summarizes these advances in order to facilitate a better understanding of electricity-driven microbial metabolism as a sustainable waste-to-resource solution.

Reactive Oxygen Species Promote Nitrous Oxide (NO) Emissions from Soil/Sediment during the Anoxic-Oxic Transition.

Reactive oxygen species (ROS)-induced element/pollutant geochemical processes in fluctuating anoxic-oxic areas have received increasing attention in recent years. Nitrous oxide (NO) is a strong greenhouse gas; however, the relationship between ROS and NO emissions in these areas has not been established. This work revealed the essential role of ROS in promoting NO emissions in soil/sediment during the anoxic-oxic transition.

Instrumental role of bioreactors in nitrate/nitrite-dependent anaerobic methane oxidation-based biotechnologies for wastewater treatment: A review.

Recently, the nitrate/nitrite-dependent anaerobic methane oxidation (n-DAMO) processes have become a research hotspot in the field of wastewater treatment. The n-DAMO processes could not only mitigate direct and indirect carbon emissions from wastewater treatment plants but also strengthen biological nitrogen removal. However, the applications of n-DAMO-based biotechnologies face practical difficulties mainly caused by the distinctive properties of n-DAMO microorganisms and the limited/availability of methane with poor solubility.