[Applications of biofilm in environmental pollution control and the related challenges].

Biofilm has been used in environmental pollution control in recent years due to its characteristics of adsorption and biodegradation. Beyond the success of its utilization in wastewater treatment, biofilm technique has high application value in the remediation of heavy metals and organic pollutants in soils. With the extensive attention and research of emerging pollutants such as microplastics and antibiotic resistance genes (ARGs), the pivotal role of biofilm can not be overlooked.

Aptamer-Embedded Zirconium-Based Metal-Organic Framework Composites Prepared by De Novo Bio-Inspired Approach with Enhanced Biosensing for Detecting Trace Analytes.

A series of Zr-based metal-organic framework (MOF) composites embedded with three kinds of aptamer strands (509-MOF@Apt) were achieved by a one-step de novo synthetic approach. A platform for ultrasensitive detection of analytes, namely, thrombin, kanamycin, and carcinoembryonic antigen (CEA), was also established. Considering the conformational changes caused by the binding interactions between aptamer strands and targeted molecules, the label-free electrochemical aptasensors based on 509-MOF@Apt composites could be developed to detect various target molecules.

Effect of migration and transformation of iron on the endogenous reduction of H2S in anaerobic landfill.

Hydrogen sulfide (H2S) is a major odor in landfill gas and needs urgent treatment. In this study, the effect of migration and transformation of iron on the endogenous reduction of H2S was investigated in two simulated landfills. The results showed that the H2S emission concentration from the landfill cover of conventional anaerobic landfill (CL) and anaerobic landfill with leachate recirculation (RL) could reach 19.

Characteristics of H2S emission from aged refuse after excavation exposure.

Hydrogen sulfide (H2S(g)) emission from landfills is a widespread problem, especially when aged refuse is excavated. H2S(g) emission from aged refuse exposed to air was investigated and the results showed that large amounts of H2S(g) can be released, especially in the first few hours after excavation, when H2S(g) concentrations in air near refuse could reach 2.00 mg m(-3).

Sulfide oxidation and nitrate reduction for potential mitigation of H2S in landfills.

Because H2S emitted by landfill sites has seriously endangered human health, its removal is urgent. H2S removal by use of an autotrophic denitrification landfill biocover has been reported. In this process, nitrate-reducing and sulfide-oxidizing bacteria use a reduced sulfur source as electron donor when reducing nitrate to nitrogen gas and oxidizing sulfur compounds to sulfate.

Water state changes during the composting of kitchen waste.

Changes in water states during the composting of kitchen waste were determined. Three experiments, R(55), R(60), and R(65), with different initial moisture contents, 55%, 60%, and 65%, respectively, were performed. Three water states, entrapped water (EW), capillary water (CW), and multiple-molecular-layer water (MMLW), were monitored during the experiments.

Bioaccessibility and health risk of heavy metals in ash from the incineration of different e-waste residues.

Ash from incinerated e-waste dismantling residues (EDR) may cause significant health risks to people through ingestion, inhalation, and dermal contact exposure pathways. Ashes of four classified e-waste types generated by an incineration plant in Zhejiang, China were collected. Total contents and the bioaccessibilities of Cd, Cu, Ni, Pb, and Zn in ashes were measured to provide crucial information to evaluate the health risks for incinerator workers and children living in vicinity.

Effects of added polyacrylamide on changes in water states during the composting of kitchen waste.

The effects of adding polyacrylamide (PAM), to attempt to delay the loss of capillary water and achieve a better level of organic matter humification, in the composting of kitchen waste were evaluated. Four treatments, with initial moisture content of 60 % were used: 0.1 % PAM added before the start of composting (R1), 0.

Reduction of heavy metals in residues from the dismantling of waste electrical and electronic equipment before incineration.

Residues disposal from the dismantling of waste electrical and electronic equipment are challenging because of the large waste volumes, degradation-resistance, low density and high heavy metal content. Incineration is advantageous for treating these residues but high heavy metal contents may exist in incinerator input and output streams. We have developed and studied a specialized heavy metal reduction process, which includes sieving and washing for treating residues before incineration.

Role of iron in H(2)S emission behavior during the decomposition of biodegradable substrates in landfill.

Hydrogen sulfide (H2S) is regarded as a major odor causing compound in landfill gas that may lead to adverse environmental and health effects. In this study, the potential role of iron in the entire life cycle of H2S production and emission was investigated during the decomposition of biodegradable substrates in the landfilled refuse. The results showed that the quantity of H2S emission decreased about 95% when Fe(OH)3 was present in the biodegradable sulfur-containing substrates.

Sorption behavior of dibutyl phthalate and dioctyl phthalate by aged refuse.

Sorption is a fundamental process controlling the transformation, fate, degradation, and biological activity of hydrophobic organic contaminants in the environment. We investigated the kinetics, isotherms, and potential mechanisms for the sorption of two phthalic acid esters (PAEs), dibutyl phthalate (DBP) and dioctyl phthalate (DOP), on aged refuse. A two-compartment first-order model performed better than a one-compartment first-order model in describing the kinetic sorption of PAEs, with a fast sorption process dominating.

[Prevalence and related factors of injury caused by agricultural machinery in the 3 provinces Shandong, Henan and Hebei of China].

Objective: To study the prevalent characteristics and related factors of injuries caused by agricultural machinery in 3 provinces Shandong, Henan and Hebei in China.

Methods: A total of 1621 agricultural machinery operators aged between 18 and 60 years old from Shandong, Henan and Hebei provinces were selected by purposive-cluster sampling method in 2009. Demographic characteristics, injury history caused by agricultural machinery in the last year and the related social and psychological factors were collected by self-designed questionnaire.

Enhanced reductive dechlorination of polychlorinated biphenyl-contaminated soil by in-vessel anaerobic composting with zero-valent iron.

Anaerobic dechlorination is an effective degradation pathway for higher chlorinated polychlorinated biphenyls (PCBs). The enhanced reductive dechlorination of PCB-contaminated soil by anaerobic composting with zero-valent iron (ZVI) was studied, and preliminary reasons for the enhanced reductive dechlorination with ZVI were investigated. The results show that the addition of nanoscale ZVI can enhance dechlorination during in-vessel anaerobic composting.

Flow analysis of heavy metals in a pilot-scale incinerator for residues from waste electrical and electronic equipment dismantling.

The large amount of residues generated from dismantling waste electrical and electronic equipment (WEEE) results in a considerable environmental burden. We used material flow analysis to investigate heavy metal behavior in an incineration plant in China used exclusively to incinerate residues from WEEE dismantling. The heavy metals tested were enriched in the bottom and fly ashes after incineration.

Dechlorination of polychlorinated biphenyl-contaminated soil via anaerobic composting with pig manure.

Anaerobic dechlorination is an effective degradation pathway of higher chlorinated polychlorinated biphenyls (PCBs). The efficiency of anaerobic composting remediation of PCB-contaminated soil using pig manure was determined. The results show that the dechlorination of PCB-contaminated soil via anaerobic composting with pig manure is feasible.

Effects of ammonia on methane oxidation in landfill cover materials.

The effects of ammonia (NH3) on CH4 attenuation in landfill cover materials consisting of landfill cover soil (LCS) and aged municipal solid waste (AMSW), at different CH4 concentrations, were investigated. The CH4 oxidation capacities of LCS and AMSW were found to be significantly affected by the CH4 concentration. The maximum oxidation rates for LCS and AMSW were obtained at CH4 concentrations of 5% and 20%(v/v), respectively, within 20 days.

Characterization of residues from dismantled imported wastes.

Residues from the imported wastes dismantling process create a great burden on the ambient environment. To develop appropriate strategies for the disposal of such residues, their characteristics were studied through background value analysis and toxicity leaching tests. Our results showed that the heavy metals concentrations in residues were high, particularly those of Cu (7180 mg kg(-1)), Zn (2783 mg kg(-1)), and Pb (1954 mg kg(-1)).

Co-digestion of kitchen waste and fruit-vegetable waste by two-phase anaerobic digestion.

The high salinity and fat contents of kitchen waste (KW) inhibits the effect of two-phase anaerobic digestion system. This research introduces fruit-vegetable waste (FVW) to alleviate the inhibition effect caused by salinity and fat concentrations, and tries to achieve an optimal addition ratio of FVW, an optimal hydraulic remain time (HRT) of acidogenic-phase reactor and methanogenic-phase reactor. A two-phase anaerobic digestion (AD) system was developed to co-dispose KW and FVW.

Effect of deposit age on adsorption and desorption behaviors of ammonia nitrogen on municipal solid waste.

Ammonia nitrogen pollution control is an urgent issue of landfill. This research aims to select an optimal refuse for ammonia nitrogen removal in landfill from the point of view of adsorption and desorption behavior. MSW (municipal solid waste) samples which deposit ages were in the range of 5 to 15 years (named as R(15), R(11), R(7), and R(5)) were collected from real landfill site.

[Transformation of dibutyl phthalate in bioreactor landfill].

Considering the refuse and leachate as one whole system, a conventional landfill (CL) was set as a control, transformation of dibutyl phthalate (DBP) in recirculated landfill (RL) and bioreactor landfill (BL) was studied. Results showed that DBP was detected in both leachate and refuse from CL, RL and BL. The initial DBP amount was 18.

Can Chlorella pyrenoidosa be a bioindicator for hazardous solid waste detoxification?

Four kinds of solid waste residue (SWR, S1 to S4) from different stages in a sequential detoxification process were chosen. The biotoxicity of the leachates from S1 to S4 was tested by Chlorella pyrenoidosa. The growth inhibition, the chlorophyll a (chla) and chlorophyll b (chlb) concentrations, and the ultrastructural morphology of cells of C.

Can a breathing biocover system enhance methane emission reduction from landfill?

Based on the aerothermodynamic principles, a kind of breathing biocover system was designed to enhance O(2) supply efficiency and methane (CH(4)) oxidation capacity. The research showed that O(2) concentration (v/v) considerably increased throughout whole profiles of the microcosm (1m) equipped with passive air venting system (MPAVS). When the simulated landfill gas SLFG flow was 771 g m(-3) d(-1) and 1028 g m(-3) d(-1), the O(2) concentration in MPAVS increased gradually and tended to be stable at the atmospheric level after 10 days.

Heavy metal source analysis in municipal solid waste (MSW): case study on Cu and Zn.

This research contributes to the knowledge of the heavy metal sources in municipal solid waste (MSW). Samples were collected from 8 cities of Zhejiang province, Eastern China. Cu and Zn, the most two conventional heavy metals with extensive distribution in many kinds of MSW components, were investigated.

Effect of liquid-to-solid ratio on semi-solid Fenton process in hazardous solid waste detoxication.

The liquid-to-solid ratio (L/S) of semi-solid Fenton process (SSFP) designated for hazardous solid waste detoxication was investigated. The removal and minimization effects of o-nitroaniline (ONA) in simulate solid waste residue (SSWR) from organic arsenic industry was evaluated by total organic carbon (TOC) and ONA removal efficiency, respectively. Initially, Box-Behnken design (BBD) and response surface methodology (RSM) were used to optimize the key factors of SSFP.

Bio-immobilization of Cu and Zn in recirculated bioreactor landfill.

Purpose: To protect the environmental quality of soil, groundwater, and surface water near the landfill site, it is necessary to make an accurate assessment of the heavy metal mobility. This study aims to present the bio-immobilization behavior of heavy metals in landfill and provide some reference suggestion for the manipulation of heavy metal pollution control after closure.

Materials And Methods: Two simulated bioreactor landfill system loaded with real municipal solid waste (MSW), namely, conventional bioreactor landfill (CL) and leachate recirculated bioreactor landfill (RL), were operated.