Waste Management

Constraints on Recycling

While people generally think that more people in London should recycle, most survey participants have deep-seated beliefs why they personally could, or should not, do more. Myths about dumping of materials collected for recycling undermine some people's psychological commitment. A significant minority also believes that the local Council does not recycle all the materials that it asks for. Indeed, many people feel that their own recycling efforts are not matched by Councils 'doing their bit'....

Landfill Design and Operation

Before constructing a landfill, detailed preparations are required by licensing authorities. Landfills consist of areas (cells) of waste, spread and compacted in discrete areas. Compaction is often carried out, using bulldozers in poorer countries, and specialised steel-wheeled compactors elsewhere. These can achieve final waste densities of more than one tonne per cubic metre (t m3), although 0.7-0.8 t m-3 is more typical. At the end of each day, or more frequently, the waste is buried with a...

Energy Recovery Options

Landfill gas is produced by the decomposition of organic wastes in the airless conditions of a landfill site. Landfill gas typically contains around 55 methane and 40 carbon dioxide together with small amounts of nitrogen, hydrogen and water. These gases can be collected using a network of horizontal pipes and wells, laid prior to and during filling of the site with waste. Beneficial use of landfill gas for energy evolved as a solution to the problem of potentially...

Damage Costs per Kilogram of Waste

It has become fashionable to carry out life cycle assessments (LCA), taking into account all stages of a process from cradle to grave. However, the appropriate system boundaries for an LCA depend on the question under consideration, a point often overlooked. For example, a cost-benefit analysis of flue gas clean up technologies for incinerators should take into account only the incineration, not other stages of waste management. A comparison of incineration with landfill should take into...

Waste Landfill

Landfill Design Stages

Landfill represents the largest route for the disposal of waste throughout Europe and North America. Landfill disposal is seen in many respects as the bottom rung of the hierarchy of waste disposal options when considering the concept of sustainable waste management. However, the modern landfill site is an advanced treatment and disposal option designed and managed as an engineering project in which the waste is degraded to a stabilised product and the product leachate is treated to minimise...

Incineration

Waste Incineration Diagram

Mass burn incineration is used for the treatment and disposal of municipal solid waste throughout the world. The composition and characteristics of the waste will influence the combustion properties and emissions produced from the combustion system. A typical calorific value for municipal solid waste is approximately 9000 kJ kg-1 ash and moisture contents tend to be high and thus in terms of a fuel the waste would compare poorly with, for example, coal. Table 6 shows typical properties of...

Composition

The composition of MSW is variable, depending on a range of factors. Household waste reflects population density and economic prosperity, seasonality, housing standards and the presence of waste minimisation initiatives (for example home composting). The prevalence of open fires in the home will affect the levels of combustible materials in the waste stream. Commercial waste will be influenced by the nature of the commerce. The composition of MSW will also depend on the specific definition of...

Subject Index

Adverse birth outcomes, 103, 116 Aerated static piles, 74 Air pollutants, classical, 174 Air pollution control, 163 Allergenic fungi, 80 Allergic asthma, 84 Allergic rhinitis, 84 Alternar a spp., 84 Ambient air quality standards, 182 Ambient bioaerosol levels, 91 Arsenic, 185 Ash residues, 163 Aspergillosis, 80, 99 Aspergillus spp., 78 Aspergillus fumigatus, 79 Asthma, allergic, 84 Atmospheric dilution, 131 Atmospheric modelling, 131 Bacillus spp., 78 Bacteria, 80 coliform, 79 psychrotrophic,...

Review of Purported Health Outcomes

This review is limited to studies of waste sites operated for the express purpose of landfilling, thus restricting the analysis to sites conforming to the generally accepted view of what constitutes a landfill. We know of 13 single-site studies covering seven such sites1,617 and an additional four relevant multiple landfill site studies.18-22 6 H. M. P. Fielder, C. Jones, S. R. Palmer, R. A. Lyons, S. Hillier and M. Joffe, Report on the Study of Time to Pregnancy in the Rhondda Valleys, Welsh...

Waste Minimisation

Waste minimisation, prevention or avoidance is the most important management technique to be applied to solid wastes, because waste which is avoided needs no management and has no environmental impact. 8 European Commission, Waste management options and climate change, ISBN 92 894 1733 1, 2001. 9 RRF, Recycling achievement in Europe, Resource Recovery Forum, 1st Floor, The British School, Otley Street, Skipton, North Yorkshire BD23 1EP, UK, 2001. General recommendations, while helpful in...

Further Study on MRFs

From the literature review, it can be determined that there are various gaps in the reported studies where there is little research concerning MRFs. This was recognised both by European BIOMED2 funding, and by the Environment Agency for England and Wales. They co-funded a study to provide information on issues such as physical and chemical hazards in MRFs, and potential bioaerosol exposures in relation to actual health effects. This study was performed in eleven MRFs throughout England and...

Health Risks of Materials Recycling Facilities

There are several types of Materials Recycling Facilities (MRFs, also known as Materials Recovery Facilities, or Materials Recycling Factories) currently in operation both in the UK and in Europe. These can generally be divided into those that sort and process construction and demolition waste, and those used to sort and process source-segregated household and commercial waste. This review will mainly concentrate on the latter, and most popular, type of MRF. MRFs that deal with household and...

Need For The Waste Manggement Preface

Waste management has become a major problem for industrialised societies. It is not that the technologies do not exist they do, and have done for many years. The main issue is that of public acceptability. The public expect to be able to produce household waste in a largely uncontrolled manner and are accustomed to an efficient local service of removal. Beyond this is where the problems begin. Once the waste is removed from the premises of the producer, most members of the public then regard...

Trends in Incineration in Europe

There is a trend towards larger, more economic plants for incineration with energy recovery with better environmental performance, improved energy efficiency and lower unit operating costs. There is also a complementary trend towards small units adapted to local geography and the desire to contain transport costs. These reflect local conditions and greater public acceptance of small units. The mid-size units (200-300000 tonnes) will be less common in the future. There is pressure for tighter...

Introduction

The composting process can be defined as the controlled biological decomposition and stabilisation of organic substrates, under conditions that are predominantly aerobic and that allow the development of thermophilic temperatures as a result of biologically produced heat. It results in a final product that has been sanitised and stabilised, is high in humic substances and can be beneficially applied to land, which is typically referred to as 'compost' (modified from Haug1). Farmers have...

Previous Research Concerning Waste Handsorting

Waste management has previously been an under-researched occupation. In the UK, accident and illness have traditionally not been separated in national health and safety statistics. Many studies are concentrated on mixed waste sorting facilities, many of which produce Refuse-Derived Fuel (RDF) for incineration. Mixed waste sorting facilities are distinct from MRFs in that the quality of recyclates recovered is lower than in a positively managed waste stream, as outlined in a recent publication...

What Is Integrated Waste Management

There are many different ways of dealing with waste in order to minimise risks to public health and the environment. For many years waste management was carried out in a piecemeal, relatively unplanned way. More recently, experience has shown that a more sustainable approach to society's uses of resources and management of wastes is needed. The term integrated waste management (IWM) is often used to describe an approach in which decisions on waste policies and practices take account of waste...

The Design of an Epidemiological Study

Epidemiology is the study of the distribution and determinants of disease in the population. 'Disease', in the context of health impact assessment of waste management, is a convenient shorthand for suboptimal health and wellbeing, in accordance with the WHO definition of Health as 'physical, mental and social well-being'. It is central to epidemiologic design that we compare groups of people. These groups may differ in one or more relevant 'risk factors'. The classic epidemiological question is...

Disease Health Measurement

Health status measurement may range from death and life threatening diseases requiring medical treatment to quality of life measures. Landfills and incinerators, for example, may impact on health through biological effects of toxic chemical exposures, or through stress associated with smell, visual, noise, local economic or other aspects of waste site operation. Stress may also occur because of fear of chemical toxicity. Understanding the pathways to ill health is important for preventive...

Confounding

To be a confounder, a factor must be a risk factor for the disease and it must be associated with the exposure of interest in the study population. Confounding can lead to either overestimation or underestimation of risk related to the exposure, depending on how the confounding factor is related to both disease and exposure. In environmental epidemiology, one of the main types of confounding of concern is socio-economic confounding. Socioeconomic status is associated with the risk of a wide...

Dispersion and Peak Concentration

For most air pollutants atmospheric dispersion is significant over hundreds to thousands of km.23 Both local and regional effects are important. We have therefore used a combination of local and regional dispersion models. To model dispersion over the short range, up to tens of km from the source, the gaussian plume is considered adequate, and we have used the ISC model,24 a gaussian plume model approved by the EPA. Over such short distances the depletion rates of the pollutants under...

Adverse Birth Outcomes

This section takes a more detailed look at all the landfill studies reporting excess risks of birth defects and low birth weight as these are the health outcomes that have been rightly or wrongly most consistently linked with landfills. The review focuses on four recent studies of UK and European landfills, as they provide the bulk of the evidence on the risks of adverse birth outcomes near landfills, they have been the subject of much scientific debate, and they illustrate some of the...

Bioaerosol Components

For the reasons described above, high concentrations of bacteria and fungi are present in composts. For example, Dees and Ghiorse19 reported total counts in the order of lO10 cells per gram of compost dry weight measured using epifluorescence microscopy, with thermophilic heterotrophic aerobes measured 13 J.G. Kleyn and T.F. Wetzler, Can. J. Microbiol., 1981, 27, 748-753. 14 J. Lacey, Ann. Agric. Environ. Med., 1997, 4, 113-121. 15 A. Ghazifard, R. Kasra-Kermanshahi and Z.E. Far, Waste Manage....

Eurohazcon Studies

The EUROHAZCON project has resulted in two multi-site landfill studies on birth defects and residence near hazardous waste landfill sites. Dolk et al examined non-chromosomal birth defects, while Vrijheid et al. examined Down's syndrome and other chromosomal defects.18'19 Non-chromosomal defects are adverse teratogenic (developmental) conditions that result from abnormal cell growth in the developing embryo or foetus. Chromosomal defects are associated with major structural mutations in the...

Compost Site Case Studies

Wheeler et al.14 investigated microbial emissions and worker health at three composting sites in the UK. These included one open windrow site processing green waste, an open windrow site processing mixed green and source separated household organic waste, and an in-vessel system processing mixed green waste, source separated household organic waste and refuse derived fuel production fines. In the investigation a range of aerobiological samplers were used to monitor airborne viable...

Sensitisation

Bunger et a .118 carried out a cross sectional study, in Germany, to look at work related health complaints and immunological markers of exposure to bioaerosols among biowaste collectors and compost workers. 58 compost workers (mean duration of employment 3 years), 53 biowaste collectors (mean duration of employment 1.5 years) and 40 controls took part. The levels of specific IgG antibodies to fungi and bacteria were measured as immunological markers of exposure to bioaerosols. At the...

Calculation of Damage

The total damage D due to a quantity Q of a pollutant is obtained by integrating the damage at a point x over all points x of the region affected by the pollutant the damage at a point x is the product of the receptor density p(x), the slope of scr of the CR function, and the concentration increment c(x) due to Q. The damage depends on the site where the pollutants are emitted. Site dependence is illustrated in Figure 3 for primary pollutants, i.e. pollutants harmful in the form emitted by a...

Claimed Recycling Habits Participation and Frequency

People typically over-claim participation in recycling schemes in questionnaire surveys. Checks in the London household survey suggest at least 10 over-claiming. Other research, which has compared claims with waste recovered, suggests much higher levels of over-claiming. Bearing in mind likely over-claiming, the household survey indicates that more than half of London households are doing little or no recycling at present. Up to another third of households are recycling but think they are doing...