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1.
Chemosphere ; 239: 124662, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31499305

RESUMO

Fluorine is the most reactive elements among the halogen group and commonly and ubiquitously occurs as fluoride in nature. The industrial processes produce fluoride by-products causing the increase of unwanted environmental levels and consequently posing risk on human and environmental health worldwide. This review gives a fundamental understanding of fluoride networks in the industrial processes, in the geological and hydrological transport, and in the biological sphere. Numerous biological pathways of fluoride also increase the risk of exposure. Literature shows that various environmental levels of fluoride due to its chemical characteristics cause bioaccumulation resulting in health deterioration among organisms. These problems are aggravated by emitted fluoride in the air and wastewater streams. Moreover, the current waste disposal dependent on incineration and landfilling superpose to the problem. In our analysis, the fluoride material flow model still follows a linear economy and reuse economy to some extent. This flow model spoils resources with high economic potential and worsens environmental problems. Thus, we intend a shift from the conventional linear economy to a circular economy with the revival of three-dimensional objectives of sustainable development. Linkages between key dimensions of the circular economy to stimulate momentum for perpetual sustainable development are proposed to gain economic, environmental and social benefits.


Assuntos
Poluentes Atmosféricos/análise , Fluoretos/análise , Eliminação de Resíduos/métodos , Desenvolvimento Sustentável/economia , Poluentes Químicos da Água/análise , Fluoretos/toxicidade , Incineração , Águas Residuárias/química
2.
Ecotoxicol Environ Saf ; 187: 109833, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31654862

RESUMO

The utilization of fish scale-derived biosorbent for immobilization of cadmium and lead in polluted sediment was thoroughly investigated in this study. Fish scale (FS) biomass was chemically and physically treated. The FS biomass treated with acid (0.1 M HCl), alkali (0.1 M NaOH) and hydrothermally, showed minimum removal capacity. While, FS treated hydrothermally along with acid showed the maximum removal efficiency of metal ions. We used different dosages (0%, 2.5%, 5%, 10%, 15%, and 20%) of FS biosorbent in the sediment. Isotherm modelling showed that this biosorbent can hold 89.30 and 92.65 mg/g of Cd and Pb on its surface. This indicated that prepared FS biosorbent has enough potential to adsorb Cd and Pb ions on its surface from the sediment. Compared to the control, sediment treated with 20% FS showed the highest immobilization capacities for Pb (92.9%), and Cd (87.9%). The values of partition coefficient (Kd) increased by 83% for Pb and 78% for Cd, which specified that availability of free ions of Pb and Cd in the aquatic system was successfully decreased. The sediment treated with 20% FS biosorbent showed 70-80% immobilization of Cd and Pb from mobile and exchangeable fractions that ultimately decreased the bioavailability of metal ions to the biota. Inclusively, compared to control, sediment served with 20% FS biosorbent showed higher level of Pb and Cd ions in residual fraction near by 80%. The prepared FS biosorbent had shown its potential in immobilizing the Cd and Pb ions from sediment as a cheap and ecologically feasible method for amendment.


Assuntos
Escamas de Animais/química , Peixes , Metais Pesados/química , Eliminação de Resíduos/métodos , Poluentes Químicos da Água/química , Adsorção , Animais , Biodegradação Ambiental , Cádmio/química , Chumbo/química
3.
Chemosphere ; 240: 124986, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31726592

RESUMO

Alkaline activation is of great potential in the solidification of municipal solid waste incineration (MSWI) fly ash, but the metallic aluminum in the ash inhibits its application. This work studies the effects of residual metallic aluminum on the expansion and microstructure of alkali-activated MSWI fly ash-based pastes. Based on the results obtained, an optimized preparation process is suggested. Characterizations of the pastes include expansion ratio, morphology (SEM), mechanical strength and microstructure (XRD and FTIR). It is confirmed that MSWI fly ash could be solidified through alkaline activation when using a small amount of coal fly ash to adjust the reactive silica and aluminum ratios. In the optimized preparation, sodium hydroxide was added separately, so that expansion in the pastes was significantly mitigated, the formation of geopolymer gel was improved and the compressive strength of the pastes increased.


Assuntos
Alumínio/química , Cinza de Carvão/química , Incineração , Eliminação de Resíduos/métodos , Resíduos Sólidos , Álcalis/química , Força Compressiva , Dióxido de Silício
4.
Chemosphere ; 238: 124574, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31445332

RESUMO

Waste landfills represent a global problem, which is more pronounced in developing countries because of the lack of resources to implement procedures that include separation and waste processing. The aim of this research was to analyze leachate and ground waters samples at the site, upstream and downstream from the landfill during different year seasons on a registered non-hazardous waste dump and to conduct physico-chemical and biological assays to determine potential risk for the ecosystem. Potential cytotoxic, prooxidative and mutagenic effects of leachates and water samples were evaluated on human laryngeal cell line (HEp2). Leachates collected at landfill site caused genotoxic effect and had a higher pH, chemical oxygen demand (COD), biochemical oxygen demand (BOD) and elevated concentrations of phosphorus, chloride, nitrogen compounds and sulphate. Genotoxicity of the leachate was increased in samples collected in dry and warm period of the year. These results are in accordance to the physico-chemical analysis which revealed that during summer period, because of intense degradation process at high temperatures increased concentrations of different chemicals can be found in leachate. Groundwater collected downstream and upstream from landfill did not show statistically significant (geno)toxic effect, irrespective of the sampling season. Chemical analysis revealed that all compounds in groundwater were below permitted values. Purification process at landfill is effective and compounds that reach groundwater do not represent a toxicological threat.


Assuntos
Água Subterrânea/química , Mutagênicos/análise , Eliminação de Resíduos/métodos , Instalações de Eliminação de Resíduos , Poluentes Químicos da Água/análise , Análise da Demanda Biológica de Oxigênio , Ecossistema
5.
An Acad Bras Cienc ; 91(4): e20180302, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31800694

RESUMO

The volume of global gross banana exports reached a record of 117.9 million tonnes in 2015 (FAO 2017), which agro-industrial wastes derived as the pseudo-stem, rachis and leaves do not have an industrial application instead they are discarded. This research study applies full factorial design and response surface methodology to determine the effect of pressing temperature and resin content on density (D), moisture (M), water absorption (WA), water swelling (WS), module of rupture (MOR), module of elasticity (MOE) and formaldehyde content (FC) of particle board made of banana pseudo-stem. A 22 factorial design was performed, factors considered were resin and temperature. The low level of resin was 15% in the coarse fiber (CF) and 35% in fine fiber (FF); high level as 25% CF and 45% FF. Temperature levels were 150ºC and 170ºC respectively. The boards met all quality parameters except ones with low resin content that didn't meet WS parameter. Furthermore, resin affected positively on WA, FC and MOE, and decreased D, WS and MOR values. Meanwhile, temperature affected negatively on D, WS, and increased FC, WA, MOE, MOR properties; none of the factors affected M response. Process conditions were optimized to 162.61°C and 43.15% FF, 23.97% CF.


Assuntos
Resíduos Industriais , Teste de Materiais , Musa , Caules de Planta , Eliminação de Resíduos/métodos , Resinas Vegetais/análise , Elasticidade , Temperatura Ambiente , Resistência à Tração
6.
Environ Monit Assess ; 192(1): 9, 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31802257

RESUMO

Solid waste is one of the important causes of the environmental crisis that negatively impacts human health throughout the world and is fast approaching a disaster level that will pose a direct threat to human life. As with all other environmental problems, the increase in solid waste production that goes hand in hand with growing population and rising consumption has become a focus of great concern. Along with these rising levels, the investment, management and maintenance of solid waste collection and transport vehicles is seeing a continual increase in financial outlay. It is clear from the budgets of local authority solid waste management systems, 65 to 80% of which are accounted for by domestic waste, that the collection and transport of solid waste is a high-cost process and that this expenditure can be significantly reduced by the reorganisation of solid waste collection routing schedules and the minimization of collection frequency. This study demonstrates a linear programming model in order to develop an optimal routing schedule for solid waste collection and transportation, thereby reducing costs to a minimum. The neighbourhood of Veysel Karani in the Haliliye District of Sanliurfa Province, Turkey, was specifically selected for this case study, having the suitable socio-economic and demographic variables to be representative of a metropolitan urban area. Firstly, the data regarding the municipal solid waste collection and transport routes were obtained from the local authority. Analysis and verification of these data were then performed. With the field study, these data were verified on-site, and the missing data were completed. Linear programming and geographic information system (GIS) analysis were used to determine the best route. Consequently, it is concluded that it is possible to save the route by 28% with GIS analysis and 33% with linear programming analysis according to the existing municipal solid waste collection and transportation routes.


Assuntos
Sistemas de Informação Geográfica , Programação Linear , Eliminação de Resíduos/métodos , Resíduos Sólidos , Gerenciamento de Resíduos/métodos , Cidades , Custos e Análise de Custo , Desastres/prevenção & controle , Monitoramento Ambiental , Humanos , Eliminação de Resíduos/economia , Eliminação de Resíduos/normas , Transportes , Turquia , Gerenciamento de Resíduos/economia
7.
Environ Monit Assess ; 191(12): 730, 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31705330

RESUMO

Sanitary landfill is still the most significant and reasonable and the least expensive waste disposal method. The process of selecting a landfill site with minimal adverse effects on the environment is a complex task, in which numerous criteria need to be taken into account. In the present research, the AHP (analytical hierarchy process) and TOPSIS (technique for order of preference by similarity to ideal solution) models were used to weigh the layers and prioritize the identified regions, respectively. In the present study, the following criteria were considered: (1) environmental criteria consisting of groundwater depth and distance from rivers, streams, and wetland/dam/lake; (2) physical criteria consisting of geology, slope percentage, distance from faults, heights, soil depth, and aspect; (3) social-economic criteria including the subcriteria land uses and distance from urban centers and villages; and finally, (4) access factors with the subcriteria distance from roads and power lines. After the preparation phase, the maps corresponding to each subscale were weighed in GIS by means of AHP. To weigh the layers and evaluate the inconsistency rate of pairwise comparisons, the Expert Choice software, in which the AHP model can be run, was used. On the output map, 11 highly suitable areas for landfill were identified via the integration of layers and the identified options and were ranked using the TOPSIS technique and five secondary criteria based on experts' views. Ultimately, area no. 12 was selected as the proposed site for the landfill in Naqadeh County. The results indicated that the combination of multicriteria decision-making models including AHP and TOPSIS can be properly utilized for the purpose of locating.


Assuntos
Monitoramento Ambiental/métodos , Sistemas de Informação Geográfica , Eliminação de Resíduos/métodos , Técnicas de Apoio para a Decisão , Irã (Geográfico) , Rios , Instalações de Eliminação de Resíduos
8.
Environ Monit Assess ; 191(12): 718, 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31691045

RESUMO

Municipal solid waste (MSW) dumpsite constitutes a major anthropogenic point source of leachate contamination to the ambient groundwater and poses a significant threat to the geo-ecosystem. This study investigated the pollution of groundwater by leachate emanating from Aba-Eku MSW dumpsite in Ibadan, Nigeria, using bacteriological, hydrochemical, and geophysical techniques. There is a diversity of bacteria in the leachate and the dominant phyla being proteobacteria (83%) and firmicutes (17%). The mean concentrations (mg/L) of Mn, Fe, Al, Cu, Mo, and Cr in the leachate samples were above the World Health Organization wastewater discharge limits. The hydrochemical parameters of the groundwater samples around the dumpsite were generally within the permissible limits, except for K and Cl-; which invariably indicate major inputs from water-rock interaction and minor contributions from the dumpsite. Three geoelectrical layers were indicated from the vertical electrical sounding data, which are the topsoil, the lateritic clay layer, and the weathered basement. Low resistivity values of 5-33 Ωm and 3-24 Ωm were obtained within 2 m and 5.5 m depths for the topsoil and the lateritic layer, respectively; while the 2-D subsurface model reveals leachate plume beyond 5 m. Although the MSW leachate is heterogeneous, the hydrochemical data show that the aquifer around the dumpsite has not been seriously polluted with the leachate, but there is a continuous percolation of leachate into the soil subsurface, based on the geophysical findings. Discontinuing waste dumping and groundwater extraction, which would over time reduce the leachate plume, are measures to enhance the groundwater quality in the area.


Assuntos
Monitoramento Ambiental , Água Subterrânea/química , Instalações de Eliminação de Resíduos , Poluentes Químicos da Água/análise , Ecossistema , Água Subterrânea/microbiologia , Nigéria , Eliminação de Resíduos/métodos , Resíduos Sólidos , Poluentes Químicos da Água/química
9.
J Environ Sci Health B ; 54(9): 791-800, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31554463

RESUMO

Sugarcane vinasse is a by-product obtained during ethanol production in sugar-ethanol plants. For each 1 L of ethanol produced approximately 11 L of vinasse are generated. As this residue is obtained in high amounts, it is used as fertilizer in sugarcane crops. However, despite being rich in nutrients, sugarcane vinasse is approximately one hundred times more polluting than domestic sewage, making it an environmental problem. Thus, the aim of the present study was to propose a treatment sequence for sugarcane vinasse and evaluate the possibility of energetic use of the generated sludge in the coagulation/flocculation stage. pH, conductivity, turbidity and decreases in UV/Vis absorption spectra were determined for each treatment step. In addition, the upper calorific value of the generated sludge was also determined, while ash (adsorption treatment) and catalyst (heterogeneous photocatalysis) characterizations were also carried out. At the end of the treatment, initial vinasse turbidity was reduced by 100% and pH and conductivity values were stabilized. The sludge presented a higher calorific value of approximately 3,000 kcal kg-1 and the ash and catalyst displayed favorable characteristics to be applied to the sugarcane vinasse treatment stages.


Assuntos
Fertilizantes/análise , Eliminação de Resíduos/métodos , Saccharum/química , Resíduos/análise , Poluição Ambiental , Saccharum/crescimento & desenvolvimento
10.
Ecotoxicol Environ Saf ; 184: 109615, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31518826

RESUMO

The mass concentrations, toxic equivalent quantity (TEQ) concentrations and congener profiles of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in the stack flue gas and ambient air of municipal solid waste incinerator (MSWI) were monitored in this study to evaluate the levels, emission characteristics, seasonal variation and emission sources of PCDD/Fs. Thirty-one ambient air samples were collected from four sites around MSWI during 2016-2017, and twelve stack flue gas samples were collected from one MSWI. Results showed that the PCDD/Fs concentrations of the stack flue gas ranged from 0.0077 to 0.021 ng I-TEQ/Nm3, with an average value of 0.016 ng I-TEQ/Nm3. The ambient air samples collected in 2016 and 2017 ranged from 0.017 to 0.27, and 0.035-0.27 pg I-TEQ/Nm3, with an average value of 0.078 and 0.10 pg I-TEQ/Nm3, respectively. The 2, 3, 4, 7, 8-PCDF always contributes most to toxicity both in stack flue gas and ambient air samples. PCDD/Fs in the ambient air of the study area showed significant seasonal differences, and the total concentration of PCDD/Fs was highest in winter, which was about 3.5-7.5 times that of summer. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) were used to determine the correlation between MSWI emissions and PCDD/Fs in ambient air. It is worth mentioning that MSWI is not the main source of PCDD/Fs in ambient air.


Assuntos
Poluentes Atmosféricos/análise , Dibenzofuranos Policlorados/análise , Dibenzodioxinas Policloradas/análise , Eliminação de Resíduos/estatística & dados numéricos , Poluentes Atmosféricos/toxicidade , China , Dibenzofuranos Policlorados/toxicidade , Monitoramento Ambiental , Gases/análise , Gases/toxicidade , Incineração , Dibenzodioxinas Policloradas/toxicidade , Eliminação de Resíduos/métodos , Estações do Ano
11.
Rev Environ Health ; 34(3): 293-301, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31494642

RESUMO

Introduction Community resilience, the ability of a community to respond positively to adverse situations, is an increasingly important topic in public health. Many resilience frameworks are grounded in concepts initially developed by ecologists to describe and explain the capacity of complex systems, such as a community, to persist or return to its original state following disturbances. As a result, much of the research on resilience is concerned with maintaining systems in their current form, preventing degradation, or promoting recovery. However, for a system that is stuck in a trap, or an unfavorable state, deliberate efforts to build the components that contribute to resilience, called adaptive capacities, may enable that system to reorganize after a disturbance to reach a more favorable state. Objective The purpose of this research was to apply a resilience framework to analyze how the community of St. Gabriel, Louisiana adapted in response to environmental change. Methods We used qualitative case-study methodologies to systematically collect newspaper articles, which served as primary data sources to examine how resilience and adaptive capacity evolved in the community of St. Gabriel, Louisiana. Results Key events in the recent history of St. Gabriel include industrial development, growing concern about environmental health and pollution, the environmental justice (EJ) movement, and the incorporation of the community as a self-governing municipality. Two events, the community's organized resistance to a large hazardous waste facility and the change in government structure, represent critical transformations, or fundamental changes in how the community functions. Conclusion The incorporation of St. Gabriel gave community members more input in planning and development decisions. As a result, the community has taken steps to improve public health in the form of zoning ordinances to prevent new exposure risks and building community infrastructure, such as a new sewer system and a recreation center.


Assuntos
Participação da Comunidade/psicologia , Exposição Ambiental/efeitos adversos , Eliminação de Resíduos/métodos , Resiliência Psicológica , Participação da Comunidade/estatística & dados numéricos , Poluentes Ambientais/efeitos adversos , Locais de Resíduos Perigosos , Humanos , Louisiana , Saúde Pública
12.
Environ Sci Pollut Res Int ; 26(30): 30711-30730, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31493083

RESUMO

One of the cheapest and proper methods for the ultimate disposal of Municipal Solid Waste (MSW) is landfilling. However, determining the location of landfill sites is a difficult and complex task due to depending on social, environmental, technical, economic, and legal factors. To solve the aforementioned challenges related to the landfill site suitability analysis, the combinations of Geographic Information System (GIS) and Multi-Criteria Decision-Making (MCDM) have been studied by academia and applied by experts over the years. This notice is apparent by the large number of academic papers which have been announced in the near future. To provide a framework of the existing literature, and to guide colleagues, a state-of-the-art of recent papers is crucial. The goal of this study is to review all scientific papers in GIS-based MCDM modeling for landfill site suitability analysis in academic journals. A total of 106 studies published between 2005 and 2019 are recorded and surveyed. The studies are then investigated and classified by a generated taxonomy including following categories: GIS software, application area, uncertainty, MCDM techniques, cell sizes in GIS, and criteria. Based on the review conducted, it is observed that while Analytical Hierarchy Process (AHP) and Weighted Linear Combination (WLC) are the most widely used MCDM methods for weighting the criteria and ranking the alternatives, respectively. On the other hand, while environmental dimension is the most commonly preferred main criteria, surface water comes first in the sub-criteria pool. Criteria analysis shows that surface and ground water, geology, land use, distance to fault zone, distance to urban areas, and distance to road and slope are the most commonly used criteria groups among others. These classifications and observations are helpful for identifying research gaps in the current literature and provide insights for future modeling and research efforts in the field.


Assuntos
Sistemas de Informação Geográfica , Resíduos Sólidos , Instalações de Eliminação de Resíduos , Técnicas de Apoio para a Decisão , Eliminação de Resíduos/métodos , Software , Incerteza
13.
Rev Environ Health ; 34(3): 235-244, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31473690

RESUMO

The presence of legacy pollutants, on-going chemical manufacturing activities, and population shifts have introduced complex, cumulative exposure risks to residents of many highly industrialized communities. These "industrial corridors" present unique challenges to environmental health science professionals, public and private sector decision makers, and residents seeking to make their communities safer and healthier. Social-ecological resilience theory offers a useful framework for the design and implementation of community engagement efforts to help stakeholders take action to reduce their exposure risks. A resilience framework views the human community as a coupled social-ecological system, wherein disturbances to the equilibrium of the system - acute and/or chronic - are common rather than rare events. It recognizes three key capacities of more resilient communities. These are the abilities of community members to self-organize to address changing threat levels, to hold scientifically sound understandings of the risks, and to learn from past experiences and take action - individually or collectively - to adapt to or mitigate the hazards in their local environment. We apply this resilience theory framework to a case study from Camp Minden, Louisiana, conducted through the Louisiana State University (LSU) Superfund Research Center's Community Engagement program and supported by the National Institute of Environmental Health Sciences (NIEHS). The case illuminates a critical path by which resilience theory can be applied to guide bi-directional communication and information-gathering, and co-development of risk-reducing strategies at the community level. These are central elements of community engagement within a contentious, real-world setting. The three components of the resilience framework were supported by specific program mechanisms and activities. The capacity for self-organization among community stakeholders was furthered through the convening of a Dialogue Committee which brought together representatives of concerned residents, regulatory agencies, research scientists, and others. This collaborative problem-solving approach supported a more holistic and scientifically sound understanding of the problem through a series of interactive meetings in which members discussed site-remediation options with thermal-treatment experts and regulators, and shared how recent explosions and concerns about air quality affected them. The members co-developed selection criteria and reached consensus on two types of disposal methods that would best reduce the significant threats to public health and the local environment. We also include a brief summary of our recent randomized survey of over 550 residents of Louisiana's industrialized communities to determine the influences on household-level adaptive behaviors to reduce acute and chronic environmental exposure risks. The results of the logistic regression analysis indicate that residents with more concern and knowledge about environmental hazards, along with confidence in their ability to implement risk-reduction measures - such as checking air-quality forecasts and then limiting outside activities - were much more likely to adopt the exposure-reducing behaviors, even when controlling for socioeconomic and demographic differences among respondents. These findings shed light on the conditions under which residents of these types of communities may be more likely to take action to reduce potential environmental exposure risks, and may help in the design of public education efforts. These "lessons learned" from Louisiana communities facing cumulative environmental exposure risks suggest that application of resilience theory to the design and implementation of community engagement programs may support the longer-term effectiveness of the efforts and enhance overall environmental health resilience. In addition, they provide practical insights about how to operationalize and apply these theoretical concepts to real-world environmental health challenges faced by residents of industrialized communities throughout the world.


Assuntos
Participação da Comunidade/psicologia , Exposição Ambiental/efeitos adversos , Eliminação de Resíduos/métodos , Resiliência Psicológica , Participação da Comunidade/estatística & dados numéricos , Poluentes Ambientais/efeitos adversos , Locais de Resíduos Perigosos , Humanos , Louisiana
14.
Artigo em Inglês | MEDLINE | ID: mdl-31405093

RESUMO

Food waste, among the organic wastes, is one of the most promising substrates to be used as a renewable resource. Wide availability of food waste and the high greenhouse gas impacts derived from its inappropriate disposal, boost research through food waste valorization. Several innovative technologies are applied nowadays, mainly focused on bioenergy and bioresource recovery, within a circular economy approach. Nevertheless, food waste treatment should be evaluated in terms of sustainability and considering the availability of an optimized separate collection and a suitable treatment facility. Anaerobic codigestion of waste-activated sludge with food waste is a way to fully utilize available anaerobic digestion plants, increasing biogas production, energy, and nutrient recovery and reducing greenhouse gas (GHG) emissions. Codigestion implementation in Europe is explored and discussed in this paper, taking into account different food waste collection approaches in relation to anaerobic digestion treatment and confirming the sustainability of the anaerobic process based on case studies. Household food waste disposal implementation is also analyzed, and the results show that such a waste management system is able to reduce GHG emissions due to transport reduction and increase wastewater treatment performance.


Assuntos
Alimentos , Eliminação de Resíduos/métodos , Resíduos , Biocombustíveis , Europa (Continente) , Gases de Efeito Estufa , Águas Residuárias
15.
Environ Monit Assess ; 191(9): 560, 2019 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-31407116

RESUMO

The possibility of disposing of fly ash (FA) and blast furnace slag (BFS), which are environmental wastes, by using them as substitutes in portland cement was examined in this study. Portland cement (CEM I), FA, BFS, CEN standard sand, and water were used in the production of mortars. Blended cements were obtained by substituting FA, BFS, and a mixture of FA and BFS (FABFS) at 5.0%, 10.0%, 15.0%, and 20.0% ratios in portland cement. Physical (Blaine area, density, initial and final setting time, and fineness), mechanical (flexural strength and compressive strength), radiation permeability (determination of linear absorption coefficient) and high-temperature experiments were performed on the FA, BFS, and FABFS samples. Mortar prism samples with a size of 40 × 40 × 160 mm were obtained using these cements. The samples were exposed to five temperatures: 20, 150, 300, 700, and 900 °C. Mortar samples kept at 20 °C were used as references. A total of 390 samples were studied under air cooling (spontaneous cooling at 20 ± 2 °C in laboratory environment). After the mortar samples reached at room temperature, flexural strength and compressive strength tests were carried out on the 28th and 90th days. The test results showed that FA, BFS, and FABFS can be used as pozzolanic additives in cement mortars both alone and together and can be applied in buildings with a high risk of fire up to certain temperature values. The sample with the highest linear absorption coefficient was the FABFS sample, and as the sample with the lowest radiation permeability, it was determined to be appropriate for use in buildings that are exposed to radiation effects.


Assuntos
Cinza de Carvão/análise , Materiais de Construção/análise , Poluentes Ambientais/análise , Eliminação de Resíduos/métodos , Resíduos Sólidos/análise , Carbono , Força Compressiva , Monitoramento Ambiental , Proteção Radiológica/métodos , Dióxido de Silício , Água
16.
Mar Pollut Bull ; 146: 282-291, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31426158

RESUMO

Historically solid waste was commonly landfilled in the coastal zone in sites with limited engineering to isolate waste from adjacent coastal environments. Climate change is increasing the likelihood that these historic coastal landfills will erode releasing solid waste to the coastal zone. Historic coastal landfills are frequently located near designated ecological sites; yet, there is little understanding of the environmental risk posed by released waste. This research investigated inorganic and organic contaminant concentrations in a range of solid waste materials excavated from two historic coastal landfills, and the potential ecological impact should eroded waste be released to the coastal environment. Contaminant concentrations in the analysed waste materials exceeded sediment quality guidelines, indicating erosion of historic coastal landfills may pose a significant environmental threat. Paper and textile wastes were found to make a significant contribution to the total contaminant load, suggesting risk assessments should consider a wide range of solid waste materials.


Assuntos
Monitoramento Ambiental/métodos , Poluentes Ambientais/análise , Eliminação de Resíduos/métodos , Resíduos Sólidos/análise , Instalações de Eliminação de Resíduos , Medição de Risco , Reino Unido
17.
Sci Total Environ ; 686: 1140-1151, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31412510

RESUMO

A novel preparation protocol for synthetic, look-a-like humic substances (i.e., fulvic and humic acids) simulating geochemical processes through hydrothermal reaction is presented, with crude waste biomass as an omnipresent and universal precursor. The chemical nature of the organic scaffold and the type and abundance of oxygen-containing functional groups of the synthetic humic substances (A-FA and A-HA) are revealed by a series of examinations. Results from EA, XPS analyze, FTIR spectra and NMR technology matched well each other, suggesting high similarity on chemical structure (abundant aromatic frameworks) and contents (e.g. N and S elements) in both humic acids. Pyrolysis-gas-chromatography/mass spectrometry (Py-GC/MS) analysis is employed on the organic structure and is directly compared to extracted natural humic matter from black soils (Harbin, China). Dehydrated carbohydrates and their condensates with low molecular weight that are rich in oxygen are the main structural components of the artificial fulvic acids, while aromatic structures and aliphatic side chains are almost absent. Aromatics (7.43%) and in some cases long-chain aliphatics (7.15%) are more prominent in the A-HA sample. The combination of the diverse analytical techniques not only allows a better understanding of artificial fulvic and humic acids, but also supports the high similarity to natural humic substances in structure and morphology. As the technology can be easily scaled and is comparable cheap, the as obtained products can be discussed to rehabilitate used up farm land.


Assuntos
Benzopiranos/análise , Poluição Ambiental/prevenção & controle , Recuperação e Remediação Ambiental/métodos , Substâncias Húmicas/análise , Eliminação de Resíduos/métodos , Resíduos Sólidos/análise , Biomassa , Solo
18.
Artigo em Inglês | MEDLINE | ID: mdl-31443319

RESUMO

Punishment policies on the inappropriate treatment of dead hogs play a key role in safeguarding public health and environmental protection. These policies aim to regulate the behavior of farmers and promote the development of sustainable agriculture. Farmers' evaluation of a policy can be used to measure its effectiveness, and loss aversion is a factor that has been little studied. This study surveyed 404 hog farmers in China, and analyzed the factors that influenced their evaluation of the penalties for the inappropriate treatment of dead hogs during 2016 and 2017. We used three indicators for the evaluation of the penalties: the degree of necessity, implementation, and effectiveness. Special attention was paid to farmers' aversion to financial penalties and police detention time, which was elicited using economic experiments. The results show that farmers are more likely to be averse to police detention time than financial penalties, and suggest that the level of each indicator needs to be increased. The results from an ordered Probit model show that there are both similarities and differences between the formation paths of the three indicators. An aversion to financial penalties will help to improve the degree of implementation. An aversion to police detention time will lead to a negative trend in the degree of effectiveness. An in-depth analysis of the factors that influence farmers' evaluation of policies to punish inappropriate treatment of dead hogs may provide a basis for the design of government policies to improve environmental protection performance.


Assuntos
Agricultura/métodos , Conservação dos Recursos Naturais/legislação & jurisprudência , Fazendeiros/psicologia , Política de Saúde , Eliminação de Resíduos/legislação & jurisprudência , Eliminação de Resíduos/métodos , Suínos , Animais , China , Conservação dos Recursos Naturais/métodos , Humanos , Inquéritos e Questionários
19.
Sci Total Environ ; 693: 133594, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31377353

RESUMO

The in-situ mitigation of methane (CH4) in landfill gas using landfill cover soil (LCS) is a cost-effective approach, but its efficiency needs to be enhanced. In this study, we incorporated an enriched methane-oxidizing bacteria (MOB) consortium into LCS and established four biochar-amended LCS groups with biochar produced at 300 °C (BC300), 400 °C (BC400), 500 °C (BC500), and 600 °C (BC600). The purpose was to evaluate the CH4 oxidation capacity of biochar-amended LCS after inoculation with MOB and to investigate how the physicochemical properties of biochar that are influenced by the pyrolysis temperature affect the performance and microbial activity of biochar-amended LCS. It was found that a 15% volume ratio (representing a mass ratio of 2.49%-2.78%) for biochar amendment in LCS enhanced CH4 removal efficiency, with the highest removal observed to be 46% for BC400-amended LCS compared to 30% for the original LCS. In addition, CH4 adsorption by the biochar was not observed, and a 15% mass ratio for biochar in the LCS had no or a negative impact. Besides improving the water-holding capacity and gas permeability of LCS, other possible advantages of biochar amendment in terms of CH4 oxidization include greater retention of nutrients, electron acceptors, and exchangeable cations, as well as introducing iron ions. It was also found that CH4 oxidation capacity and the methanotroph activity of biochar-amended LCS did not continue to increase with higher pyrolysis temperatures, even though higher micropore volumes and surface areas were obtained at higher pyrolysis temperatures. From this study, BC400 was identified as the optimal choice for the best performance in terms of enhancing both the CH4 oxidation capacity of the amended LCS and the growth of type II methanotroph Methylocystaceae, which can possibly be attributed to having the highest cation exchange capacity of the four biochars.


Assuntos
Metano/química , Eliminação de Resíduos/métodos , Temperatura Ambiente , Instalações de Eliminação de Resíduos , Carvão Vegetal/química , Solo/química
20.
Artigo em Inglês | MEDLINE | ID: mdl-31295944

RESUMO

Anaerobic fermentation is a cost-effective biowaste disposal approach. During fermentation, microorganisms require a trace amount of metals for optimal growth and performance. This study investigated the effects of metal mixtures on biogas properties, process stability, substrate degradation, enzyme activity, and microbial communities during anaerobic fermentation. The addition of iron (Fe), nickel (Ni), and zinc (Zn) into a copper (Cu)-stressed fermentation system resulted in higher cumulative biogas yields, ammonia nitrogen (NH4+-N) concentrations and coenzyme F420 activities. Ni and Zn addition enhanced process stability and acetate utilization. The addition of these metals also improved and brought forward the peak daily biogas yields as well as increased CH4 content to 88.94 and 86.58%, respectively. Adding Zn into the Cu-stressed system improved the abundance of Defluviitoga, Fibrobacter and Methanothermobacter, the degradation of cellulose, and the transformation of CO2 to CH4. The bacterial and archaeal communities were responsible for the degradation of lignocelluloses and CH4 production during the fermentation process. This study supports the reutilization of heavy metal-contaminated biowaste and provides references for further research on heavy metals impacted anaerobic fermentation.


Assuntos
Biodegradação Ambiental , Poluentes Ambientais/metabolismo , Fermentação/fisiologia , Metais Pesados/metabolismo , Microbiota/fisiologia , Eliminação de Resíduos/métodos , Anaerobiose , Biocombustíveis/análise , Biocombustíveis/microbiologia , Reatores Biológicos , Metano , Eliminação de Resíduos/instrumentação
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