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1.
Bioresour Technol ; 326: 124754, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33524883

RESUMEN

To support smart city in terms of municipal waste management and bioenergy recovery, a high-solid anaerobic membrane bioreactor (AnMBR) was developed for sewage sludge (SeS) and food waste (FW) treatment in this study. COD mass balance showed that 54.1%, 66.9%, 73.5%, 91.4% and 93.5% of the COD input was converted into methane at the FW ratio of 0, 25%, 50%, 75% and 100%, respectively. The corresponding net energy balance was 13.6, 14.1, 17.1, 22.9 and 27.4 kJ/g-VS, respectively. An important finding of this investigation was that, for the first time, the relationship between net energy balance and carbon to nitrogen (C/N) ratio was revealed and the established sigmoid-type function was shown to be capable of predicting energy balance at different C/N ratios regardless of the region. The outcomes of this study show the potential of high-solid AnMBRs in SeS and FW treatment for supporting smart cities in the future.


Asunto(s)
Eliminación de Residuos , Aguas del Alcantarillado , Anaerobiosis , Reactores Biológicos , Digestión , Alimentos , Metano , Eliminación de Residuos Líquidos
2.
Environ Monit Assess ; 193(2): 69, 2021 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-33464420

RESUMEN

The objective of this paper is to offer an approach to assess the risk associated with Municipal Solid Wastes, in a geospatial context. Initially, a risk index including hazard, vulnerability and other important variables was built. The built model is based on multi-criteria evaluation techniques and geographic information systems. Subsequently, the constructed index was used to model possible damage in various municipalities of the state of Chiapas, Mexico. The results indicate that the highest levels of risk are found in places with unfavorable conditions, such as high rates of waste generation, low waste collection coverage, steep slopes, etc. that cover 6.22% of the study area. The areas with high risk level are mainly found in the southeast of the municipalities of Villa Corzo and Villaflores, and cover 27.06% of the study area. The places of low and very low risk levels are concentrated in the center and northeast of the study area, in the municipalities of Suchiapa, Chiapa de Corzo and Acala, and cover 38.6% of the area. At the municipal level, Berriozábal, Villaflores and Villa Corzo have the highest levels of risk in most of their territory; the high levels of risk presented in Berriozábal are due to the limited territorial area that it occupies in the study area. In Villaflores and Villa Corzo, the high levels of risk are due to the high population dispersion. A large part of Tuxtla Gutiérrez territory presents low and medium risk levels, especially within the population settlement. The peripheral areas show the highest levels of risk, because the waste collection service is not provided very often. Finally, the Cohen's kappa statistic used to validate the precision of the model gave a value of 0.34, which means that the spatial model can be considered acceptable despite its low value. Although this work is only a general approach to spatial risk modeling at a regional scale, it provides interesting information. Moreover, it adds to the few efforts that exist in the literature to model the risk associated with wastes.


Asunto(s)
Eliminación de Residuos , Administración de Residuos , Ciudades , Monitoreo del Ambiente , Sistemas de Información Geográfica , México , Residuos Sólidos
3.
Ecotoxicol Environ Saf ; 208: 111596, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33396117

RESUMEN

The surge in solid waste (SW) has become major issues in the fields of public health and ecological environment fuelled by the rapid development of social economy. The fate of nitrogen contained in SW (SWN) varies with different treatment methods, which will affect the environment to varying degrees. It is of great practical and guiding significance to comprehensively evaluate the sources, fate and its cascading effects of SWN. Here, a systematic SWN flow evaluation of the generation, treatment and emissions in China from 2008 to 2017 was established. During this period, the SWN flow and the N pollution emissions from SW treatment increased by 19.7% and 27.6% respectively, with the domestic garbage being the largest contributor. This shows that it is particularly important to reinforce the classified of domestic garbage and resource recycling in China. Landfill was the main treatment, accounting for 51.8% of the total SWN. Landfill and incineration were the main sources of pollution N emissions, while compost treatment has the lowest contribution rate. It highlights the urgency of changing the waste treatment methods in China. About 92.3% of the N pollution emissions was lost to the atmosphere and 7.7% to the groundwater. NH3 and NOx were the main pollutants to the atmosphere. Special attention is paid to the reduction and control of NH3 in landfill, dumping and compost processes, while NOx in incineration. This study provides scientific basis for management and disposal of SW, so as to reduce its impact on the ecological environment and develop more sustainable policies for China and other developing countries.


Asunto(s)
Nitrógeno/análisis , Eliminación de Residuos/métodos , Residuos Sólidos/análisis , China , Ambiente , Contaminación Ambiental , Incineración/métodos , Reciclaje , Instalaciones de Eliminación de Residuos
4.
Waste Manag ; 121: 286-295, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33406476

RESUMEN

The redistribution of unsold food products to charities is often considered a promising strategy to reduce food waste at supermarkets while producing social advantages. The Italian law against food waste (so-called "Gadda law") approved in 2016 allows municipalities to reduce the waste tax due by retail stores, proportionally to the certified amount of surplus food they donate. This option may act as an economic incentive for retailers to activate food waste redistribution initiatives, thus supporting diffusion at a larger scale. This study uses a simple economic model to assess the gains and losses of the municipality and the retailers under different scenarios of the application of this tax reduction. The model is tested on a number of Italian municipalities with different features, showing that under the appropriate conditions a decrease in the waste tax for stores activating food redistribution can lead to a win-win economic condition for all the actors involved.


Asunto(s)
Alimentos , Eliminación de Residuos , Ciudades , Italia , Impuestos
5.
Waste Manag ; 121: 373-382, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33422924

RESUMEN

A previously developed surface probe method, which allows for instantaneous methane (CH4) flux measurement, was used to establish CH4 emission maps of a municipal landfill with a final clay cover and equipped with a gas recollection system. In addition to spatial variations, the method was applied at 7 different times over a total timeframe of 65 h and under similar weather conditions to determine the intrinsic temporal variations of CH4 emissions; i.e., the temporal variation related to the dynamic of the landfill rather than the one driven by external factors. Furthermore, continuous CH4 fluxes, with a data acquisition frequency of 1 Hz, were measured during 12 h at a single position, and for one hour at 22 locations of the landfill, spanning a large range of CH4 emission magnitudes. A simple model for the numerical characterization of spatiotemporal variability of the landfill emission was used and allowed us to separately quantify the temporal and spatial variability. This model showed that, in the landfill tested, the temporal distribution of CH4 emissions resulted more homogeneous than the spatial distribution. Other attributes of the temporal and spatial distributions of CH4 emissions were also established including the anisotropic nature of the spatial distribution and, contrastingly, the stochastic temporal variability of such emissions.


Asunto(s)
Contaminantes Atmosféricos , Eliminación de Residuos , Contaminantes Atmosféricos/análisis , Metano/análisis , Instalaciones de Eliminación de Residuos
6.
Waste Manag ; 121: 412-421, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33445114

RESUMEN

Municipal solid waste incineration fly ash (MSWI-FA) has been regulated as a hazardous waste that needs to treat with stabilization, solidification and landfill due to its amount of heavy metals, chlorides, sulfates and dioxin. While the proper treated MSWI-FA can be utilized as pozzolanic material to reduce the usage of Portland cement. The present article aims to develop an integrated wet-extraction and carbonation process for MSWI-FA stabilization, solidification and utilization via the high-gravity technology. A benchtop experiment demonstrated the dechlorination and CO2 sequestration of MSWI-FA and the carbonated product was applied as a supplementary cementitious material (SCM) in the cement mortar. Physical, chemical and thermal characteristics of raw, wet-extracted, and carbonated MSWI-FA were addressed in terms of the mean diameter, micropore area, micropore volume, chemical compositions, mineralogy and morphology. The effects of the liquid-to-solid ratio and high gravity factor were evaluated. Overall, a chloride extraction ratio of 36.35% and a CO2 capture capacity of 258.5 g-CO2 kg-FA-1 were achieved in the batch experiment. The results of water-energy consumption of chloride removal and CO2 fixation provided a novel insight into the future process criterion. In addition, the carbonated FA was found as binder to partially substitute Portland cement due to its large content of calcium carbonate. The workability and mechanical strength of cement mortar with partial substitution of stabilized FA were evaluated to determine the potential FA utilization pathway. Finally, the continuous process tests determined the key operation indexes for future process scale-up.


Asunto(s)
Hipergravedad , Metales Pesados , Eliminación de Residuos , Carbono , Dióxido de Carbono , Ceniza del Carbón , Incineración , Metales Pesados/análisis , Material Particulado , Residuos Sólidos/análisis
7.
Waste Manag ; 121: 441-451, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33450650

RESUMEN

Proper management of urban waste might support sustainable and circular development, while mismanagement increases both costs and socio-environmental negative outcomes. In particular, the organic fraction constitutes the largest share of urban waste. In the circular economy framework, it is described as a valuable resource, to be converted into soil improver, biogas and energy. The aim of the paper is to propose a Decision Support System (DSS) for policymakers, based on linear programming techniques. This model is expected to improve the current methodologies for planning and managing organic fraction of municipal solid waste and provide useful insights about public resources allocation. The proposed optimization model is tested on Campania Region (Italy), which is a clear example of the negative implications of improper waste management. Based on the goals recently set by Campania regional government, the model allows to select the most cost-effective and sustainable solutions for treating organic waste. Results show three different scenarios associated to the impacts that each possible outcome has on the stated objectives. The "Ideal Solution" is not achievable, but it is used as a benchmark; the "Max NPV Solution" is feasible, but it reports several major drawbacks. Finally, the "Best Compromise Solution" allows to increase regional composting capability by six time and biogas availability by seven times, with environmental implications that are very similar to the ideal ones.


Asunto(s)
Compostaje , Eliminación de Residuos , Administración de Residuos , Italia , Residuos Sólidos/análisis
8.
Waste Manag ; 121: 365-372, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33477055

RESUMEN

The service life of high-density polyethylene (HDPE) geomembranes is directly determined by the landfill environment, and the antioxidant depletion stage is the first and most important stage of the HDPE geomembrane aging process. In this study, the antioxidant depletion stage was chosen to investigate the effects of different exposure environments on the HDPE geomembrane lifespan. The antioxidant depletion rate (ADR) and the antioxidant depletion time (ADT) of HDPE geomembranes under various exposure conditions were calculated based on the aging parameters obtained by fitting the collected reported data with the Arrhenius model. Also, the influence of exposure conditions on the HDPE geomembrane performance degradation was analyzed. The results showed that the aging method had the greatest effect on the antioxidant depletion period, while the HDPE geomembrane thickness had the least effect. The ADR sensitivity to brand/material, aging method, leachate components, and exposure medium decreased with increasing temperature; only the sensitivity to thickness showed a slight increasing tendency with increasing temperature. The ADTs of HDPE geomembranes under different exposure conditions ranged from 6 years to 900 years, indicating that the HDPE geomembranes can complete the service time of landfills under reasonable exposure conditions. This study provides a reliable methodological basis for the risk control and life prediction of HDPE geomembranes.


Asunto(s)
Polietileno , Eliminación de Residuos , Antioxidantes , Temperatura , Instalaciones de Eliminación de Residuos
9.
Bioresour Technol ; 323: 124585, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33385628

RESUMEN

The effect of biochar addition on the microbial community and methane (CH4) production during anaerobic digestion was experimentally investigated, focusing on the role of minerals in biochar. The biochar was prepared from pine sawdust by pyrolysis at 650 °C and 900 °C, respectively, and a subsample was leached with citric acid. The cultures with the addition of biochar, leached biochar, Fe, and leached biochar combined with Fe, respectively, were placed in bench-scale bioreactors for anaerobic digestion. Daily biogas production was measured by volume displacement method and analysed for CH4 concentration, which allowed the cumulative CH4 yield (YM) and daily CH4 production rate (RM) to be determined. Culture samples were also taken daily for volatile fatty acids (VFAs) and microbial community analysis. Compared to the control without biochar addition, the addition of raw biochar significantly increased YM by 46.9% and RM by 43.0%, while leached biochar only increased the YM by 33.2% and RM by 18.2%, respectively. The Fe-containing minerals in biochar were found to enhance VFA degradation and increase population of Clostridia and Methanosaeta, improving the CH4 production.


Asunto(s)
Microbiota , Eliminación de Residuos , Anaerobiosis , Reactores Biológicos , Carbón Orgánico , Alimentos , Metano , Minerales
10.
Bioresour Technol ; 323: 124597, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33387710

RESUMEN

Biodiesel production using microbial oil derived from food waste discarded by the hospilatity sector could provide a sustainable replacement for diesel fuel. Discarded potato peels were used in solid-state fermentations of Aspergillus awamori for the production of glucoamylase (30 U/g) and protease (50 U/g). Hospitality food waste hydrolysis led to 98% (w/w) starch to glucose conversion yields. Crude hydrolyzates were used in shake flask fermentations with the oleaginous yeast Rhodosporidium toruloides Y-27012 leading to 32.9 g/L total dry weight (TDW) with 36.4% (w/w) intracellular lipid content. Fed-bath bioreactor cultures resulted in TDW of 53.9 g/L and lipid concentration of 26.7 g/L. Principal component analysis showed a fatty acid profile similar to soybean oil and solid food waste oil. Microbial oil was transesterified into biodiesel with satisfactory performance considering the European standard EN 14214. This work demonstrated that valorization of food waste for biodiesel production is feasible.


Asunto(s)
Biocombustibles , Eliminación de Residuos , Aspergillus , Alimentos , Rhodotorula
11.
Environ Pollut ; 271: 116279, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33387777

RESUMEN

This paper provides an example of the kind of analysis needed to support better targeted policies to reduce the environmental impacts of agricultural activities, using the specific case of Anaerobic Digestion (AD) to treat animal manure and other agricultural and food wastes in British Columbia (BC). Economic and life cycle environmental performance metrics are estimated to compare integrated and stand-alone systems using the resulting biogas and digestate. Using biogas for heating outperforms purifying it for distribution as renewable natural gas (RNG). However, current policy and energy prices in BC perversely support RNG, making biogas-fired heating systems economically unattractive. The performance of biogas-fired heating system can be improved and their dependence on subsidies reduced by integration with local agricultural activities, exploiting CO2 and digestate as by-products. Biogenic CO2, from combustion of the biogas and from mushroom cultivation, can displace natural gas use in producing CO2-enriched atmospheres to enhance growth rates in greenhouse production. Using digestate as growing media in greenhouses and mushroom cultivation can generate significant revenues but the environmental benefits are nugatory. Co-digestion of food waste can further improve performance by increasing biogas yield. With all extra benefits combined, integrated AD systems can increase both GHG mitigation and revenues by at least 80%. The analysis illustrates the general point that, to avoid perverse outcomes, policy measures must support options based on their actual GHG mitigation benefits, rather than targetting any specific technology.


Asunto(s)
Eliminación de Residuos , Anaerobiosis , Animales , Biocombustibles , Colombia Británica , Alimentos , Formulación de Políticas
12.
Bioresour Technol ; 323: 124618, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33406468

RESUMEN

Food waste (FW) is an abundant resource with great potential for lactic acid (LA) production. In the present study, the effect of storage time on FW characteristics and its potential for LA production was investigated. The largest part of sugars was consumed during 7 to 15 days of FW storage and the sugar consumption reached 68.0% after 15 days. To enhance the LA production, micro-aerobic conditions (13 mL air/g VS) and addition of ß-glucosidase were applied to improve polysaccharides hydrolysis, resulting to increase of monosaccharides content to 76.6%. Regarding fermentative LA production, the highest LA titer and yield of hydrolyzed FW was 32.1 ± 0.5 g/L and 0.76 ± 0.01 g/g-sugar, respectively. Furthermore, L-LA isomer was higher than 70% when FW was stored for up to 7 days. However, attention should be paid on controlling the FW storage to approximately one week.


Asunto(s)
Alimentos , Eliminación de Residuos , Fermentación , Hidrólisis , Ácido Láctico
13.
Water Environ Res ; 93(2): 306-315, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33428300

RESUMEN

Municipal wastewater has recently attracted interest in relation to anaerobic wastewater treatments. Biogas production with co-digestion of mixed substrates has been proposed and has many potential benefits for municipal wastewater. The aim of this research was to assess the performance of biogas production during co-digestion of municipal wastewater and food waste under semi-continuous and continuous operation with various hydraulic retention times (HRTs). A laboratory-scale continuous stirred tank reactor (CSTR) at room temperature operation (27-32°C) was employed in this research. The highest methane yields of 167.41 ± 66.52, 194.35 ± 85.44, and 214.81 ± 85.44 ml/g-Vs were found in semi-continuous mode, respectively, at 30, 10, and 10 days of HRTs with a 10:90 ratio of municipal wastewater to food waste (based on TS). Result finding of optimum condition (10 days of HRTs) presented a methane yield of 485.58 ± 82.35 ml/g with continuous operation. Hence, food waste has practical implications for use as a co-substrate with the optimization condition of HRT and operation mode for biogas production from municipal wastewater. PRACTITIONER POINTS: Food waste has good potential for use as a co-substrate for biogas production from municipal wastewater. HRT reduction from 30 to 10 days in semi-continuous, biogas production from municipal wastewater and food waste increased by 59%. Co-digestion of municipal wastewater and food waste with continuous mode and 10 days of HRT was the effective biogas production.


Asunto(s)
Eliminación de Residuos , Aguas Residuales , Anaerobiosis , Biocombustibles/análisis , Reactores Biológicos , Digestión , Alimentos , Metano , Aguas del Alcantarillado
14.
Ecotoxicol Environ Saf ; 208: 111655, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33396169

RESUMEN

An enormous amount of oil-containing drill cuttings have been produced by the marine oil and gas industry. The environmental impacts of discharged drilling waste have been extensively studied. However, there is still an urgent need to develop alternative methods to identify the genotoxicity of untreated and treated drill waste in a timely manner before it is discharged. In this study, we developed a relatively rapid, sensitive, and accurate genotoxicity-detection method using Comet assay and the marine benthic goby Mugilogobius chulae. This goby is sensitive to a standard toxicant mitomycin C (MMC). The optimal exposure period for genotoxicity detection using M. chulae was determined. Three genotoxic indices (tail length (TL), tail DNA content (TD), and tail moment (TM)) were used to assess the effectiveness of high-temperature treatment of oil-contaminated waste. Untreated oil-containing drill cuttings exhibited the highest genotoxicity to goby cells. Genotoxicity was dramatically reduced after thermal treatment of drill cuttings at 350 °C and 500 °C. TD and TM exhibited significant correlation with the concentration of total petroleum hydrocarbons (TPHs)/total polycyclic aromatic hydrocarbons (PAHs) according to Pearson and Mantel correlation analyses (P values were <0.05). Using redundancy analysis (RDA) and variation partition analysis (VPA), the genotoxic effects of the drill cuttings were ascribed to total alkanes and specific groups of PAHs. In conclusion, this newly established biological model has the potential to be widely used to detect the genetic damage of untreated or treated oil-containing drill cuttings discharged into the marine environment.


Asunto(s)
Daño del ADN , Monitoreo del Ambiente/métodos , Peces/genética , Petróleo/toxicidad , Contaminantes Químicos del Agua/toxicidad , Animales , Ensayo Cometa , Peces/fisiología , Calor , Hidrocarburos/análisis , Hidrocarburos/toxicidad , Yacimiento de Petróleo y Gas/química , Petróleo/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Hidrocarburos Policíclicos Aromáticos/toxicidad , Eliminación de Residuos , Contaminantes Químicos del Agua/análisis
15.
Waste Manag ; 122: 124-131, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33513532

RESUMEN

Approximately 90% of medical waste generated in the operating room (OR) is considered to be non-infectious and non-regulated (Wyssusek, Keys & van Zundert, 2019). Frequently, this waste is inappropriately disposed of into infectious regulated medical waste containers. Due to differences in waste treatment, improper segregation can lead to the misuse or inappropriate allocation of resources, environmental pollution, and increased cost for institutions. A waste segregation initiative was instituted in a tertiary care medical center in the anesthesia work-space of 35 ORs. This initiative included education of medical waste management to increase anesthesia staff knowledge and compliance with waste segregation and optimization of existing waste disposal containers to decrease waste disposal costs. After implementation, there was an increase in overall provider knowledge (p < 0.001) particularly in the categories of medication vial disposal, medication disposal and identification of items for disposal in the sharps containers (p ≤ 0.05). Data suggests a 34.7% increase in providers reporting to always practice waste segregation (p ≤ 0.05). Additionally, there was a statistically significant decrease in overall weight of regulated medical waste items from 0.33 kg/case to 0.09 kg/case (p < 0.001). This decrease in regulated waste supports an improvement in waste segregation and inappropriate items being disposed of in the general trash container. The omission of inappropriate waste was further confirmed by a segregation audit that showed an overall increase in correctly segregated regulated waste of 65%. Collectively, this lead to a cost savings of $15.60 per OR per week, or $28,392 annually.


Asunto(s)
Anestesia , Eliminación de Residuos Sanitarios , Residuos Sanitarios , Eliminación de Residuos , Administración de Residuos , Humanos
16.
Sci Total Environ ; 765: 144632, 2021 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-33412377

RESUMEN

With the implementation of new domestic garbage classification policy in China, attention is growing to improve the treatment efficiency of municipal 'wet' waste. Combing with the new regulation, the synergistic strategy and the microbial ecology of the anaerobic co-digestion (AcoD) of cooked food waste (CFW), uncooked food waste (UCFW) and rice straw (RS) were analyzed in current study. Results showed that the maximum cumulative methane yield (CMY) and synergic index were obtained when CFW and UCFW were mixed at the ratio of 1:1 (based on volatile solid content). The highest CMY 452.94 ± 0.99 mL/g-VS was obtained when the ratio of CFW, UCFW and RS was 0.81:0.09:0.10, which was 16.29%, 36.20% and 121.84% higher than their mono-digestion, respectively. The AcoD promoted the methane potential by prolonging the release time of organic matter and slowing down the hydrolysis rate. Furthermore, the AcoD increased the species diversification and relative abundance of fermentation bacteria in digesters, and Methanosaeta predominated the methanogen communities. This study demonstrated a clean and sustainable AcoD strategy for safe disposal of urban food waste and revealed the variation of microbial community, which can provide a base for efficient bioenergy recovery from urban domestic garbage.


Asunto(s)
Residuos de Alimentos , Eliminación de Residuos , Anaerobiosis , Reactores Biológicos , China , Digestión , Alimentos , Metano , Aguas del Alcantarillado
17.
Ecotoxicol Environ Saf ; 211: 111913, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33493721

RESUMEN

Effective management of municipal solid waste (MSW) is essential for the conservation of ecosystems in the Qinghai-Tibetan Plateau (QTP). Considering the landfill is the major method of MSW management, the factors influencing groundwater contamination near MSW landfill sites in the QTP were studied, based on field investigations, environmental impact assessment, and meteorological and hydrogeological analyses. Results indicated that the groundwater was contaminated heavily by nitrate (PI = 7.5), particularly in the landfill without an anti-seepage system, followed by nitrite (PI = 3.5) and heavy metals including arsenic (PI = 4.1) and hexavalent chromium (PI = 2.8). Total hardness, total dissolved solids, nitrate, and lead in the groundwater near the investigated landfill sites were significantly different between the monsoon and the cold seasons. Both the rainfall infiltration and the leachate infiltration were considerably limited by environmental characteristics in the QTP, including high evaporation, low rainfall, and the presence of permafrost. Soil sample contamination near landfill sites was considered as moderate (28.6% of the soil samples) and moderate to heavy (71.4% of the soil samples), based on the geoaccumulation index of mercury. However, comparatively low generation and concentrations of leachate and good topsoil quality (PI = 0.84) reduced the quantity of pollutants infiltrating into the groundwater. The alkaline leachate (pH = 7.45-9.23) and soil (pH = 7.08-8.72) also considerably decreased the concentrations of contaminants dissolved in the infiltrated rainfall and leachate. Additionally, low groundwater level can delay preferential flow and enhance attenuation. Therefore, the groundwater contamination near the landfill sites was simply point pollution, which was influenced by leachate, soil, climate, and hydrogeology characteristics in the QTP. The anti-seepage system is a potential strategy for use in the prevention of groundwater contamination by MSW landfills in the QTP.


Asunto(s)
Monitoreo del Ambiente , Agua Subterránea/química , Instalaciones de Eliminación de Residuos , Contaminantes Químicos del Agua/análisis , Ecosistema , Agua Subterránea/análisis , Metales Pesados/análisis , Nitratos/análisis , Eliminación de Residuos/métodos , Estaciones del Año , Suelo , Residuos Sólidos/análisis , Tibet , Administración de Residuos
18.
Appetite ; 160: 105110, 2021 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-33428972

RESUMEN

The COVID-19 pandemic has profoundly disrupted household food purchasing and preparation, including elements identified as important drivers of household food waste. The two main aims of this study were (1) to examine changes in food waste behaviors since the start of the COVID-19 pandemic in the U.S. and Italy; and (2) to investigate potential predictors of food waste behavior, including avoidance of supermarkets, increased home cooking, and increased role of health concerns in food choices. A sample of n = 478 (79% female) individuals from the U.S., mean (SD) age = 30.51 (10.85), and n = 476 individuals from Italy, (78% female), mean (SD) age = 33.84 (12.86), completed an online survey between April 8th and April 28th 2020. Just under half of respondents (49%) reported decreased food waste since the start of the pandemic. Rates were significantly higher among the U.S. sample (61.5%, n = 294) compared to the Italian sample (38%, n = 180). Controlling for the time since restrictions were introduced, age, gender, and perceived financial security, logistic regression revealed greater reduction in food waste since the beginning of the pandemic for U.S. individuals relative to participants from Italy (OR = 0.47, p < .001). In addition, increased importance of health concerns when making food choices (OR = 1.34, p < .005) as well as more frequent cooking (OR = 1.35, p < .001), and greater avoidance of supermarkets (OR = 1.15, p = .049) were associated with greater probability of less food waste. Scarcity and greater reliance on cooking may encourage individuals to reflect on food waste practices. Further research should explore how these factors may be targeted to reduce food waste beyond the pandemic.


Asunto(s)
Comportamiento del Consumidor , Alimentos , Residuos de Alimentos , Adulto , Femenino , Conductas Relacionadas con la Salud , Humanos , Italia , Masculino , Persona de Mediana Edad , Pandemias , Eliminación de Residuos , Encuestas y Cuestionarios , Estados Unidos , Adulto Joven
19.
Mar Pollut Bull ; 163: 111986, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33461078

RESUMEN

Small-sized plastic debris (micro- and mesoplastics) are emerging pollutants and widely detected in aquatic environments. However, micro- and mesoplastics pollution research with regard to landfills is limited. In this study, the occurrence, characteristics, and possible release of micro- and mesoplastic waste from the Galuga landfill leachate to the aquatic environment were studied. Micro- and mesoplastics were identified in all surface water samples from leachate influent and effluent of Galuga landfills. The average daily release to the aquatic environment was estimated at 80,640 ± 604.80 microplastic and 618,240 ± 1905.45 mesoplastic particles, respectively. The amount of microplastic increased three-fold and nine-fold for mesoplastics after input from the leachate drain. Micro- and mesoplastic main chemical compositions were polyethylene, polypropylene, polystyrene, polyethylene terephthalate, polyester, and cellophane. This study implied that the leachate may cause micro and mesoplastic contamination to the aquatic environment. The results raised the knowledge of small-sized plastic debris in aquatic environments.


Asunto(s)
Eliminación de Residuos , Contaminantes Químicos del Agua , Indonesia , Microplásticos , Plásticos , Residuos Sólidos/análisis , Instalaciones de Eliminación de Residuos , Contaminantes Químicos del Agua/análisis
20.
Bioresour Technol ; 325: 124693, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33465646

RESUMEN

In this study, the effects of adding different food waste proportions (volatile solids ratio of 3:7, 5:5, 7:3) to tylosin fermentation dreg on anaerobic digestion were investigated. The results showed that the co-digestion group (294-399 mL·g-VS-1) increased methane production by 14.8%-55.5% compared with tylosin fermentation dreg alone-digestion (256 mL·g-VS-1). The correlation analysis showed that pH, total volatile fatty acids and acetic acid were the most important factors affecting cumulative methane production. Tylosin in the solid and liquid phases decreased significantly after anaerobic digestion, indicating that tylosin could be effectively removed by co-digestion, and the total removal rate was 68.2%-83.7%. Therefore, due to the satisfactory methane yield and the tolerable tylosin removal rate, it is feasible to make the co-digestion of tylosin fermentation dreg and food waste.


Asunto(s)
Alimentos , Eliminación de Residuos , Anaerobiosis , Reactores Biológicos , Digestión , Fermentación , Metano , Aguas del Alcantarillado , Tilosina
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