Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 17 de 17
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
Waste Manag ; 70: 22-29, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28889991

RESUMEN

With the increase in composting asa sustainable waste management option, biological air pollution (bioaerosols) from composting facilities have become a cause of increasing concern due to their potential health impacts. Estimating community exposure to bioaerosols is problematic due to limitations in current monitoring methods. Atmospheric dispersion modelling can be used to estimate exposure concentrations, however several issues arise from the lack of appropriate bioaerosol data to use as inputs into models, and the complexity of the emission sources at composting facilities. This paper analyses current progress in using dispersion models for bioaerosols, examines the remaining problems and provides recommendations for future prospects in this area. A key finding is the urgent need for guidance for model users to ensure consistent bioaerosol modelling practices.


Asunto(s)
Contaminación del Aire/estadística & datos numéricos , Compostaje , Monitoreo del Ambiente/métodos , Modelos Químicos , Aerosoles/análisis , Microbiología del Aire , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis
2.
Waste Manag ; 61: 40-57, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28139367

RESUMEN

Waste management processes generally represent a significant loss of material, energy and economic resources, so legislation and financial incentives are being implemented to improve the recovery of these valuable resources whilst reducing contamination levels. Material recovery and waste derived fuels are potentially valuable options being pursued by industry, using mechanical and biological processes incorporating sensor and sorting technologies developed and optimised for recycling plants. In its current state, waste management presents similarities to other industries that could improve their efficiencies using process analytical technology tools. Existing sensor technologies could be used to measure critical waste characteristics, providing data required by existing legislation, potentially aiding waste treatment processes and assisting stakeholders in decision making. Optical technologies offer the most flexible solution to gather real-time information applicable to each of the waste mechanical and biological treatment processes used by industry. In particular, combinations of optical sensors in the visible and the near-infrared range from 800nm to 2500nm of the spectrum, and different mathematical techniques, are able to provide material information and fuel properties with typical performance levels between 80% and 90%. These sensors not only could be used to aid waste processes, but to provide most waste quality indicators required by existing legislation, whilst offering better tools to the stakeholders.


Asunto(s)
Residuos Sólidos/análisis , Administración de Residuos/métodos , Carbono , Contaminantes Ambientales/análisis , Fluorescencia , Interacciones Hidrofóbicas e Hidrofílicas , Rayos Láser , Metano , Microondas , Óptica y Fotónica/métodos , Tamaño de la Partícula , Reciclaje/métodos , Eliminación de Residuos/métodos , Ultrasonido/métodos , Administración de Residuos/instrumentación
3.
J Environ Manage ; 184(Pt 2): 448-455, 2016 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-27743831

RESUMEN

Bioaerosols are released in elevated quantities from composting facilities and are associated with negative health effects, although dose-response relationships are not well understood, and require improved exposure classification. Dispersion modelling has great potential to improve exposure classification, but has not yet been extensively used or validated in this context. We present a sensitivity analysis of the ADMS dispersion model specific to input parameter ranges relevant to bioaerosol emissions from open windrow composting. This analysis provides an aid for model calibration by prioritising parameter adjustment and targeting independent parameter estimation. Results showed that predicted exposure was most sensitive to the wet and dry deposition modules and the majority of parameters relating to emission source characteristics, including pollutant emission velocity, source geometry and source height. This research improves understanding of the accuracy of model input data required to provide more reliable exposure predictions.


Asunto(s)
Contaminantes Atmosféricos/análisis , Modelos Teóricos , Suelo , Administración de Residuos/métodos , Aerosoles , Humanos
4.
Waste Manag ; 40: 9-13, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25827256

RESUMEN

An experimental study was completed using a previously developed and innovative image analysis approach, which has been applied here to shredded waste materials representative of waste-derived fuels. Waste components were collected from source-segregated recycling containers and shredded to <150 mm. These materials were then used to produce 3× samples of different composition. The samples were spread to represent materials on a conveyor belt, and multiple images of each sample were captured using 10×10 cm and 20×20 cm quadrats. The images were processed using ERDAS Imagine software to determine the area covered by each waste component. This coverage was converted into a mass using density data determined as part of this study, yielding a determined composition which was then compared with the known composition of the samples. The image analysis results indicated a strong correlation with the actual values (mean r=0.89). The area coverage of the sample (10×10 cm or 20×20 cm) contributes to the accuracy as the dot-grid approach used with the particle size within the samples may result in components not being sufficiently monitored. This manuscript presents initial results of the application of an adapted innovative image-based method, and critically assesses how the technique could be improved and developed in the future.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Reciclaje/métodos , Eliminación de Residuos/métodos , Eliminación de Residuos Líquidos/métodos , Residuos/análisis , Algoritmos , Biocombustibles/análisis , Biomasa , Radioisótopos de Carbono/química , Europa (Continente) , Tamaño de la Partícula , Reproducibilidad de los Resultados , Programas Informáticos
5.
Waste Manag ; 34(7): 1101-8, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24565805

RESUMEN

This research classifies the physical morphology (form and structure) of bioaerosols emitted from open windrow composting. Aggregation state, shape and size of the particles captured are reported alongside the implications for bioaerosol dispersal after release. Bioaerosol sampling took place at a composting facility using personal air filter samplers. Samples were analysed using scanning electron microscopy. Particles were released mainly as small (<1 µm) single, spherical cells, followed by larger (>1 µm) single cells, with aggregates occurring in smaller proportions. Most aggregates consisted of clusters of 2-3 particles as opposed to chains, and were <10 µm in size. No cells were attached to soil debris or wood particles. These small single cells or small aggregates are more likely to disperse further downwind from source, and cell viability may be reduced due to increased exposure to environmental factors.


Asunto(s)
Aerosoles/análisis , Microbiología del Aire , Microscopía Electrónica de Rastreo , Material Particulado/análisis , Instalaciones de Eliminación de Residuos
6.
Waste Manag ; 34(1): 219-25, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24064376

RESUMEN

The thermal processing of waste materials, although considered to be an essential part of waste management, is often sharply contested in the UK. Arguments such as health, depletion of resources, cost, noise, odours, traffic movement and house prices are often cited as reasons against the development of such facilities. This study aims to review the arguments and identify any effect on property prices due to the public perception of the plant. A selection of existing energy from waste (EfW) facilities in the UK, operational for at least 7 years, was selected and property sales data, within 5 km of the sites, was acquired and analysed in detail. The locations of the properties were calculated in relation to the plant using GIS software (ArcGIS) and the distances split into 5 zones ranging from 0 to 5 km from the site. The local property sale prices, normalised against the local house price index, were compared in two time periods, before and after the facility became operational, across each of the 5 zones. In all cases analysed no significant negative effect was observed on property prices at any distance within 5 km from a modern operational incinerator. This indicated that the perceived negative effect of the thermal processing of waste on local property values is negligible.


Asunto(s)
Incineración/economía , Opinión Pública , Contaminación del Aire , Cambio Climático , Comercio , Fuentes Generadoras de Energía , Sistemas de Información Geográfica , Ruido , Salud Pública , Reino Unido
7.
Waste Manag ; 33(11): 2449-56, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23876718

RESUMEN

Two novel techniques are presented in this study which together aim to provide a system able to determine the renewable energy potential of mixed waste materials. An image analysis tool was applied to two waste samples prepared using known quantities of source-segregated recyclable materials. The technique was used to determine the composition of the wastes, where through the use of waste component properties the biogenic content of the samples was calculated. The percentage renewable energy determined by image analysis for each sample was accurate to within 5% of the actual values calculated. Microwave-based multiple-point imaging (AutoHarvest) was used to demonstrate the ability of such a technique to determine the moisture content of mixed samples. This proof-of-concept experiment was shown to produce moisture measurement accurate to within 10%. Overall, the image analysis tool was able to determine the renewable energy potential of the mixed samples, and the AutoHarvest should enable the net calorific value calculations through the provision of moisture content measurements. The proposed system is suitable for combustion facilities, and enables the operator to understand the renewable energy potential of the waste prior to combustion.


Asunto(s)
Procesamiento de Imagen Asistido por Computador , Energía Renovable , Residuos/análisis , Microondas
8.
Waste Manag ; 32(2): 245-8, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22019051

RESUMEN

An experimental study was undertaken to assess the suitability of an image-based approach for determining the physical composition of mixed wastes. Waste samples were investigated at six different waste sorting facilities each visited twice during the study. These materials were physically sorted to examine the composition of these materials; during each of these surveys the waste was also processed to obtain digital images covering an area of 30 m(2), representing approximately 250-500 kg (3× mechanical bucket loads) of mixed waste. The images were processed using ERDAS Imagine software to assess the area covered by each component within the waste material. The composition determined from the image analysis was compared with results from the physical hand sorting. The image analysis results indicated a strong correlation with the physical results (mean r=0.91), however it was evident that components such as film plastics and paper were being over-estimated by the image analysis approach. This manuscript provides initial results, demonstrating the potential of an image-based method, and discusses further research requirements and future applications of this technique.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Eliminación de Residuos/métodos , Residuos/análisis , Residuos/clasificación , Inglaterra
9.
Int J Hyg Environ Health ; 214(5): 376-83, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21737345

RESUMEN

The emission and dispersal of bioaerosols from open-air commercial composting facilities continues to be contentious. A meta-dataset enumerating cultivable microorganism emission and downwind concentrations is not yet available. A dataset derived from repeated and replicated field studies over a period of two years at two commercial composting facilities is presented. The data characterises patterns in Aspergillus fumigatus, actinomycetes, Gram-negative bacteria and endotoxin emission and downwind concentrations. For all bioaerosols, compost agitation activities had a significant impact on concentrations; levels were variable up to 600 m downwind from site. Bioaerosols declined rapidly from source and exhibited a secondary peak 100-150 m from site boundary. All bioaerosols were found downwind from site in elevated concentrations. Compared to those found 100 m upwind, levels were significantly higher at 180 m downwind for A. fumigatus; at 300-400 m for actinomycetes and Gram negative bacteria, and at 100 m for endotoxins. Periodically, elevated concentrations could be found for all bioaerosols at distances further downwind. The evidence provided by this data set provides operators and regulators of facilities with reliable data to inform the location, risk assessment and bioaerosol sampling strategies of commercial composting facilities.


Asunto(s)
Microbiología del Aire , Contaminantes Atmosféricos/análisis , Endotoxinas/análisis , Monitoreo del Ambiente , Residuos de Alimentos , Eliminación de Residuos , Aspergillus fumigatus , Comercio , Bacterias Gramnegativas , Suelo
10.
Waste Manag ; 31(6): 1176-83, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21288710

RESUMEN

An experimental study was undertaken to compare the differences between municipal solid waste (MSW) derived solid recovered fuel (SRF) (complying with CEN standards) and refuse derived fuel (RDF). Both fuels were co-combusted with coal in a 50 kW fluidized bed combustor and the metal emissions were compared. Synthetic SRF was prepared in the laboratory by grinding major constituents of MSW such as paper, plastic, textile and wood. RDF was obtained from a local mechanical treatment plant. Heavy metal emissions in flue gas and ash samples from the (coal+10% SRF) fuel mixture were found to be within the acceptable range and were generally lower than that obtained for coal+10% RDF fuel mixture. The relative distribution of heavy metals in ash components and the flue gas stream shows the presence of a large fraction (up to 98%) of most of the metals in the ash (except Hg and As). Thermo-gravimetric (TG) analysis of SRF constituents was performed to understand the behaviour of fuel mixtures in the absence and presence of air. The results obtained from the experimental study will enhance the confidence of fuel users towards using MSW-derived SRF as an alternative fuel.


Asunto(s)
Carbón Mineral/análisis , Incineración , Eliminación de Residuos/métodos , Residuos/análisis , Aire , Carbono/química , Ceniza del Carbón , Metales Pesados/análisis , Material Particulado/química , Eliminación de Residuos/instrumentación , Termogravimetría
11.
Environ Technol ; 33(15-16): 1699-707, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22439555

RESUMEN

The identification of risk and its appropriate allocation to partners in project consortia is essential for minimizing overall project risks, ensuring timely delivery and maximizing benefit for money invested. Risk management guidance available from government bodies, especially in the UK, does not specify methodologies for quantitative risk assessment, nor does it offer a procedure for allocating risk among project partners. Here, a methodology to quantify project risk and potential approaches to allocating risk and their implications are discussed. Construction and operation of a waste management facility through a public-private finance contract are discussed. Public-private partnership contracts are special purpose vehicle (SPV) financing methods promoted by the UK government to boost private sector investment in facilities for public service enhancement. Our findings question the appropriateness of using standard deviation as a measure for project risk and confirm the concept of portfolio theory, suggesting the pooling of risk can reduce total risk and its impact.


Asunto(s)
Administración de Residuos/economía , Gestión de Riesgos , Incertidumbre
12.
Environ Technol ; 31(14): 1507-16, 2010 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-21275248

RESUMEN

An existing materials flow model is adapted (using Excel and AMBER model platforms) to account for waste and hidden material flows within a domestic environment. Supported by national waste data, the implications of legislative change, domestic resource depletion and waste technology advances are explored. The revised methodology offers additional functionality for economic parameters that influence waste generation and disposal. We explore this accounting system under hypothetical future waste and resource management scenarios, illustrating the utility of the model. A sensitivity analysis confirms that imports, domestic extraction and their associated hidden flows impact mostly on waste generation. The model offers enhanced utility for policy and decision makers with regard to economic mass balance and strategic waste flows, and may promote further discussion about waste technology choice in the context of reducing carbon budgets.


Asunto(s)
Conservación de los Recursos Naturales/economía , Conservación de los Recursos Naturales/tendencias , Predicción , Modelos Econométricos , Eliminación de Residuos/economía , Reología , Residuos/economía , Simulación por Computador , Reino Unido
13.
Waste Manag ; 29(8): 2289-97, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19443201

RESUMEN

This paper reports an integrated appraisal of options for utilising solid recovered fuels (SRF) (derived from municipal solid waste, MSW) in energy intensive industries within the United Kingdom (UK). Four potential co-combustion scenarios have been identified following discussions with industry stakeholders. These scenarios have been evaluated using (a) an existing energy and mass flow framework model, (b) a semi-quantitative risk analysis, (c) an environmental assessment and (d) a financial assessment. A summary of results from these evaluations for the four different scenarios is presented. For the given ranges of assumptions; SRF co-combustion with coal in cement kilns was found to be the optimal scenario followed by co-combustion of SRF in coal-fired power plants. The biogenic fraction in SRF (ca. 70%) reduces greenhouse gas (GHG) emissions significantly ( approximately 2500 g CO(2) eqvt./kg DS SRF in co-fired cement kilns and approximately 1500 g CO(2) eqvt./kg DS SRF in co-fired power plants). Potential reductions in electricity or heat production occurred through using a lower calorific value (CV) fuel. This could be compensated for by savings in fuel costs (from SRF having a gate fee) and grants aimed at reducing GHG emission to encourage the use of fuels with high biomass fractions. Total revenues generated from coal-fired power plants appear to be the highest ( 95 pounds/t SRF) from the four scenarios. However overall, cement kilns appear to be the best option due to the low technological risks, environmental emissions and fuel cost. Additionally, cement kiln operators have good experience of handling waste derived fuels. The scenarios involving co-combustion of SRF with MSW and biomass were less favourable due to higher environmental risks and technical issues.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Fuentes Generadoras de Energía , Incineración/métodos , Residuos , Ciudades , Conservación de los Recursos Naturales/economía , Conservación de los Recursos Naturales/legislación & jurisprudencia , Electricidad , Fuentes Generadoras de Energía/economía , Fuentes Generadoras de Energía/legislación & jurisprudencia , Incineración/economía , Centrales Eléctricas/clasificación , Centrales Eléctricas/economía , Centrales Eléctricas/legislación & jurisprudencia , Factores de Riesgo , Reino Unido , Residuos/economía
14.
Bioresour Technol ; 100(11): 2747-61, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19216072

RESUMEN

Biodrying is a variation of aerobic decomposition, used within mechanical-biological treatment (MBT) plants to dry and partially stabilise residual municipal waste. Biodrying MBT plants can produce a high quality solid recovered fuel (SRF), high in biomass content. Here, process objectives, operating principles, reactor designs, parameters for process monitoring and control, and their effect on biodried output quality are critically examined. Within the biodrying reactors, waste is dried by air convection, the necessary heat provided by exothermic decomposition of the readily decomposable waste fraction. Biodrying is distinct from composting in attempting to dry and preserve most of biomass content of the waste matrix, rather than fully stabilise it. Commercial process cycles are completed within 7-15 days, with mostly H(2)O((g)) and CO(2) loses of ca. 25-30% w/w, leading to moisture contents of <20% w/w. High airflow rate and dehumidifying of re-circulated process air provides for effective drying. We anticipate this review will be of value to MBT process operators, regulators and end-users of SRF.


Asunto(s)
Reactores Biológicos/microbiología , Desecación/instrumentación , Desecación/métodos , Modelos Biológicos , Eliminación de Residuos/instrumentación , Eliminación de Residuos/métodos , Biodegradación Ambiental , Ingeniería Biomédica/instrumentación , Ingeniería Biomédica/métodos , Diseño de Equipo , Análisis de Falla de Equipo
15.
Environ Int ; 32(8): 1010-20, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16860388

RESUMEN

The European waste sector is undergoing a period of unprecedented change driven by business consolidation, new legislation and heightened public and government scrutiny. One feature is the transition of the sector towards a process industry with increased pre-treatment of wastes prior to the disposal of residues and the co-location of technologies at single sites, often also for resource recovery and residuals management. Waste technologies such as in-vessel composting, the thermal treatment of clinical waste, the stabilisation of hazardous wastes, biomass gasification, sludge combustion and the use of wastes as fuel, present operators and regulators with new challenges as to their safe and environmentally responsible operation. A second feature of recent change is an increased regulatory emphasis on public and ecosystem health and the need for assessments of risk to and from waste installations. Public confidence in waste management, secured in part through enforcement of the planning and permitting regimes and sound operational performance, is central to establishing the infrastructure of new waste technologies. Well-informed risk management plays a critical role. We discuss recent developments in risk analysis within the sector and the future needs of risk analysis that are required to respond to the new waste and resource management agenda.


Asunto(s)
Contaminación Ambiental/análisis , Residuos Peligrosos/análisis , Medición de Riesgo/métodos , Administración de la Seguridad/métodos , Administración de Residuos/métodos , Salud Ambiental , Contaminación Ambiental/efectos adversos , Residuos Peligrosos/efectos adversos , Medición de Riesgo/tendencias , Administración de la Seguridad/tendencias , Factores de Tiempo
16.
Water Sci Technol ; 50(4): 17-23, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15484738

RESUMEN

Annoyance is a familiar reaction to odours arising from wastewater treatment sites, a reaction which can result in complaints and prosecutions. Odour management plans can be used to assess the extent of nuisance caused and prioritise mitigation measures. Often, these plans have been developed purely on the basis of technical assessments of emission and dispersion, with the general aim of limiting odour concentrations to a specific threshold at some distance from the works. They have often been prepared with inconsistent communication between the site staff and consultant during the development process, and may not directly refer to the affected population. This paper describes a risk-based approach to developing odour management plans, in which mitigation measures are assessed and prioritised on the basis of the likely frequency and intensity of odour exposure. A key element of the approach is the use of knowledge from data gained from key stakeholder groups: customers, staff, and regulators. Emphasis is placed on the development of clear communications between these groups, which helps both in terms of raising awareness amongst operators as to the significance of odour problems, and also in managing the expectations of customers and regulators. The practical application of this approach is demonstrated by the development of odour management plans for wastewater treatment sites by Yorkshire Water Services Ltd. These have used data from staff, customers and regulators to develop risk grids, which are then used to prioritise remediation measures. Involving staff in the data collection operations has been successful in raising awareness of the significance of odours, and has in turn led to low-cost emission reductions through improved housekeeping. Improved communications between operators, customers and regulators has led to more realistic expectations with regard to odour problems, a situation which can reduce conflict and prevent the imposition of stringent and sometimes unrealistic odour standards.


Asunto(s)
Comunicación , Contaminación Ambiental/prevención & control , Odorantes/prevención & control , Eliminación de Residuos Líquidos/métodos , Recolección de Datos , Humanos , Competencia Profesional , Política Pública , Valores de Referencia , Gestión de Riesgos
17.
Water Sci Technol ; 50(4): 225-32, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15484765

RESUMEN

An economical and practical alternative to the standard end-of-pipe odour control methods is the application of liquid odour control products. Currently, there are no established product-testing methods. The data that are available are often of questionable quality and may have limited relevance to waste management. Waste facilities receive differing streams of waste at varying loading volumes. Whilst in operation this exposes control products to a wide variety of environmental conditions, further increasing the difficulty of selecting an effective means of control. The current study initially identifies commercially available odour control products applicable for solid and liquid waste management operations. Bench-scale batch absorption tests have been carried out to investigate odorous gas abatement for a range of selected commercial products and water at a range of pH values. Hydrogen sulphide was the test odorous gas, as it is commonly associated with waste processes. Gas-phase volumetric mass-transfer coefficients (KGa) have been calculated to determine mass-transfer performance. The development of a pilot-scale spray tower is then presented as the testing apparatus for future work. This is an attempt to construct a repeatable testing method for evaluating abatement performance of odour control products, and control the problems encountered when applying odour control products to open sites. KGa values and data collected from tests in this study will be considered in future work as design parameters for the rig.


Asunto(s)
Contaminantes Atmosféricos/aislamiento & purificación , Odorantes/prevención & control , Absorción , Sulfuro de Hidrógeno/aislamiento & purificación , Control de Calidad , Eliminación de Residuos Líquidos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...