Larger aggregate formed by self-assembly process of the mixture surfactants enhance the dissolution and oxidative removal of non-aqueous phase liquid contaminants in aquifer.

Surfactants can transfer non-aqueous phase liquid (NAPL) contaminants to the aqueous phase, and enhance the removal of the latter in groundwater. However, the extensive use of surfactants causes secondary contamination and increases the non-target consumption of oxidants. It is pressing to develop a surfactant with high phase transfer efficiency and sound compatibility with oxidants to minimize the use of surfactants for groundwater remediation.

Antibiotic resistance genes and heavy metals in landfill: A review.

Landfill is reservoir containing antibiotic resistance genes (ARGs) that pose a threat to human life and health. Heavy metals impose lasting effects on ARGs. This review investigated and analyzed the distribution, composition, and abundance of heavy metals and ARGs in landfill.

Volatile and semi-volatile organic compounds in landfill leachate: Concurrence, removal and the influencing factors.

Volatile and semi-volatile organic compounds (VOCs and SVOCs) carried by landfilled wastes may enter leachate, and require appropriate treatment before discharge. However, the driving factors of the entry of VOCs and SOVCs into leachate, their removal characteristics during leachate treatment and the dominant factors remain unclear. A global survey of the VOCs and SOVCs in leachate from 103 landfill sites combined with 27 articles on leachate treatment was conducted to clarify the abovementioned question.

A novel process for food waste recycling: A hydrophobic liquid mulching film preparation.

Appropriate and effective recycling of food waste (FW) has become increasingly significant with the promotion of garbage classification in China. In this study, a novel and green process was developed to recycle FW to prepare a biodegradable composite liquid mulching film (LMF) through crosslinking with sodium alginate (SA). The solid phase of FW was obtained as the raw material after hydrothermal pretreatment to remove pathogens and salts, and to improve the reactivity of active components at a moderate temperature.

Recent progress on in-situ chemical oxidation for the remediation of petroleum contaminated soil and groundwater.

Accidental oil leaks and spills can often result in severe soil and groundwater pollution. In situ chemical oxidation (ISCO) is a powerful and efficient remediation technology. In this review, the applications and recent advances of three commonly applied in-situ oxidants (hydrogen peroxide, persulfate, and permanganate), and the gap in remediation efficiency between lab-scale and field-scale applications is critically assessed.

[Different Responses of Soil Dissolved Organic Matter to Different Types of Compost].

This study explored the responses of soil dissolved organic matter (DOM) to the application of different types of compost using a soil sample without compost as a control. Ultraviolet and fluorescence spectrum technology and EEM-PARAFAC was used to analyze DOM structure and driving factors in soil added with different proportion of cow dung compost (SCC), food and kitchen waste compost (SFC), and sludge compost (SCC). Compared with the control group, contents of AN, NH-N, DOC, and SOM in soil added with compost were significantly increased, and contents of SOM and DOC increased with the increasing of compost amount.

Molecular structure and evolution characteristics of dissolved organic matter in groundwater near landfill: Implications of the identification of leachate leakage.

Landfills can cause groundwater contamination, the pollution characteristics in groundwater near landfill sites have been extensively investigated, while the rapid identification of leachate leakage remained unclear. Comprehensively characterizing dissolved organic matter (DOM) is crucial for tracing the source, species, and migration of contaminants within groundwater and protecting groundwater sources. Here, we showed that DOM composition from newer landfills was mainly composed of newly-produced tryptophan and tyrosine, and protein-like and humic-like substances were more abundant in landfills that were relatively older.

[Pollution Characteristics and Health Risk Assessment of Heavy Metals in the Water of Lijiang River Basin].

In order to clarify the pollution levels of heavy metals in the drinking water sources of the Lijiang River Basin, surface water samples were collected from 62 sites throughout the Lijiang River during May 2019. Heavy metals, including As, Cd, Cr, Mn, Cu, Zn, Hg, Co, and Sb, in the water samples were analysed. Health risk assessments associated with these nine heavy metals were conducted using the health risk assessment model from the US EPA.

Effects of landfill refuse on the reductive dechlorination of pentachlorophenol and speciation transformation of heavy metals.

Landfill refuse is a mixture of inorganic minerals and organic matter that is capable of undergoing complexation and redox reactions due to its active functional groups. Organic matter often combines with minerals in landfill refuse and it remains unclear whether this combination involves electron transfer. Therefore, the effects of landfill refuse composition on reductive dechlorination and speciation transformation of heavy metals were investigated in this study.

Surfactant-enhanced remediation of oil-contaminated soil and groundwater: A review.

Oil leakage, which is inevitable in the process of extraction, processing, transportation and storage, seriously undermines the soil and groundwater environment. Surfactants can facilitate the migration and solution of oil contaminants from nonaqueous phase liquid (NAPL) or solid phase to water by reducing the (air/water) surface tension, (oil/water) interfacial tension and micellar solubilization. They can effectively enhance the hydrodynamic driven remediation technologies by improving the contact efficiency of contaminants and liquid remediation agents or microorganism, and have been widely used to enhance the remediation of oil-contaminated sites.

[Different Responses of Soil Microbial Community Structure to Irrigation with Treated Wastewater from Domestic and Industrial Sources].

To investigate the long-term effects of irrigation with treated domestic and industrial wastewater on the microbial community structure of the soil, Illumina MiSeq high-throughput sequencing technology was applied. Groundwater irrigated soil was used as a control. The effects of soil environmental factors and their interactions on the microbial community structure were investigated.

Evolution properties and dechlorination capacities of particulate organic matter from a landfill.

Particulate organic matter (POM) includes humin and non-degradable residues, and the knowledge about its composition, evolution and environmental behavior is limited. The composition, evolution and its influence on dechlorination of the POM in landfill was studied. The results show that POM accounts for 27 %-57 % of the organic matter in landfill cell, which is mainly composed of protein-, fulvic- and humic-like components.

Interaction and coexistence characteristics of dissolved organic matter with toxic metals and pesticides in shallow groundwater.

The long-term and large-scale utilization of fertilizers and pesticides in facility agriculture leads to groundwater pollution. However, the coexistence and interactions between organic fertilizers (i.e.

Removal and dissipation pathway of typical fluoroquinolones in sewage sludge during aerobic composting.

To observe the effect of aeration strategies on the dissipation of fluoroquinolones (FQs) during aerobic composting and explore their dissipation pathways, 60-L composting and 0.5-L incubation experiments were carried out in this study. Three aeration strategies (windrow, static aeration, feedback aeration) were applied to remove two typical FQs (Norfloxacin (NOR) and Ofloxacin (OFL)) during the 60-L composting of sewage sludge with 5 mg kg of FQs added.

Redox properties and dechlorination capacities of landfill-derived humic-like acids.

Electron transfer capacities (ETC) of humic-like acids (HLA) and their effects on dechlorination are dependent on their redox-active properties. Aging and minerals can affect the chemical compositions and structures of HLA. However, the underlying mechanism and the impacts on the dechlorination capacities of HLA are poorly understood.

Redox properties of compost-derived organic matter and their association with polarity and molecular weight.

Compost-derived dissolved organic matter (DOM), which has a wide distribution of molecular weight (MW) and polarity, has a potential application in the remediation of the contaminated soil due to its redox-active functional groups. Composting treatment can change the MW and polarity of the DOM through microbial transformation and degradation. However, the relationship between the redox properties of compost-derived DOM and its MW and polarity is still unclear.

Hydrophobicity-dependent electron transfer capacities of dissolved organic matter derived from chicken manure compost.

The electron transfer capacities (ETC) of dissolved organic matter (DOM) are related to their hydrophobicity. However, the underlying mechanism is poorly understood. The DOM was extracted from chicken manure compost, and fractionated into four fractions based on hydrophobicity, i.

[Degradation of Pentachlorophenol by Fulvic Acid in a Municipal Solid Waste Landfill].

The structural composition and functional group changes in fulvic acid (FA) at various landfills were studied using ultraviolet and infrared spectroscopy. The electron transfer ability of FA and its ability to degrade pentachlorophenol (PCP) were also studied considering the various landfills. The results showed that the use of MR-1 as an electron donor and the simultaneous addition of fulvic acid in different stages as an electron shuttle can significantly increase the degradation rate of PCP, leading it beyond 80%.

[Vertical Spatial Distribution of Denitrification Intensity in the Vadose Zone of Typical Sections of Chaobai River Alluvial Fan].

In this study, the Chaobai River alluvial fan area, Beijing City, was chosen as the study area, and two typical profiles (S6 and S8) were selected to determine the denitrification intensity value of the vadose zone at different sampling depths (0-10 m). The vertical spatial distribution of denitrification in the vadose zone was analyzed, and the influencing factors of the vertical distribution of denitrification strength in the aeration zone were identified. The results showed that the NO-N concentrations in the denitrification process of soil samples in different vadose zones experienced three main stages:rising, falling, and rising.

Succession and diversity of microbial communities in landfills with depths and ages and its association with dissolved organic matter and heavy metals.

Landfill is an important method for the treatment of municipal solid wastes. Microbes play a central role in the biodegradation and stabilization of organic matter during landfill; however, the succession of microbial communities in landfills and their association with organic matter still remain unclear. This study investigated the succession and diversity of microorganisms in landfill depending on different depths and ages as well as its association with dissolved organic matter (DOM) and heavy metals.

[Composition, Evolution, and Complexation of Dissolved Organic Matter with Heavy Metals in Landfills].

Samples of wastes and leachates were collected from a landfill site and a leachate treatment plant[i.e., equalization basin, anaerobic zone, oxidation ditch, and membrane bioreactor (MBR) section].

Insights into the redox components of dissolved organic matters during stabilization process.

The changes of dissolved organic matter (DOM) components during stabilization process play significant effects on its redox properties but are little reported. Composting is a stabilization process of DOM, during which both the components and electron transfer capacities (ETCs) of DOM change. The redox components within compost-derived DOM during the stabilization process are investigated in this study.

Investigating the composition characteristics of dissolved and particulate/colloidal organic matter in effluent-dominated stream using fluorescence spectroscopy combined with multivariable analysis.

Fluorescence excitation-emission matrix (EEM) spectroscopy combined with principal component analysis (PCA) and parallel factor analysis (PARAFAC) were used to investigate the compositional characteristics of dissolved and particulate/colloidal organic matter and its correlations with nitrogen, phosphorus, and heavy metals in an effluent-dominated stream, Northern China. The results showed that dissolved organic matter (DOM) was comprised of fulvic-like, humic-like, and protein-like components in the water samples, and fulvic-like substances were the main fraction of DOM among them. Particulate/colloidal organic matter (PcOM) consisted of fulvic-like and protein-like matter.

Spectroscopic characterization of DOM and the nitrogen removal mechanism during wastewater reclamation plant.

The performance of the Sha-he wastewater reclamation plant was evaluated in this study. To remove residual nitrogen after Anaerobic-Anoxic-Oxic (A2O) treatment, three multistage Anoxic-Oxic (A/O) were added to investigate the nitrogen removal efficiency and its mechanism. In addition, the constituents and evolution of dissolved organic matter (DOM) during wastewater reclamation was also investigated using a method combining fluorescence spectroscopy with fluorescence regional integration (FRI).

Metaproteomics analysis of the functional insights into microbial communities of combined hydrogen and methane production by anaerobic fermentation from reed straw.

A metaproteomic approach was used to analyse the proteins expressed and provide functional evidence of key metabolic pathways in the combined production of hydrogen and methane by anaerobic fermentation (CHMP-AF) for reed straw utilisation. The functions and structures of bacteria and archaea populations show significant succession in the CHMP-AF process. There are many kinds of bacterial functional proteins, mainly belonging to phyla Firmicutes, Proteobacteria, Actinobacteria and Bacteroidetes, that are involved in carbohydrate metabolism, energy metabolism, lipid metabolism, and amino acid metabolism.