Transcript
WASTE MANAGEMENT
INTRODUCTION
• Generation of solid waste increases every year• Decrease of number of available landfills• Concerns about risks associated with disposal• Opposition to siting new waste management
facilities• Increased awareness of environmental
problems• Increase in costs associated with waste
management
Who is responsible?
• Local, state and federal governments have underestimated the issue.
• Industry has produced goods with little regard to eventual disposal.
• Individuals consume products and generate waste with little regard to disposal.
• Disposal facility owners regard environmental issues as secondary.
Definitions of waste
• Household waste– Waste from residences – organic, recyclables,
gardenwaste, etc– Source separated or mixed– Not hazardous waste – oil, paint, pesticides, cleaners
• Industrial and commercial waste– all sources of waste that are not collected at the
kerbside – restaurants, shops, offices, workshops, etc– largest component is wastewater sludge
Definitions of waste (cont.)
• Construction waste– building and demolition sites
– Variable composition with inerts (soils, cement, bricks), biodegradables (vegetation from land clearing) and hazardous waste (paints, solvents, glues etc)
• Agricultural wastes– Plant and animal residues
Definitions of waste (cont.)
• Regulated wastes– overtly dangerous materials– organic solvents, grease trap waste, oils, heavy
metal solutions, medical waste, caustic or acidic chemicals and explosives, tyres, pathogenic (hospital)
Waste is a resource
• Recyclables– Paper– Glass– Plastic– Aluminium and Ferrous metal– Building materials– Industrial recyclables– fly ash, water– Compost, soil conditioner
• Energy– Conversion to methane– Direct incineration
Waste Management Hierarchy
• Reducing the quantity and toxicity of waste.
• Reusing the materials.
• Recycling and recovering materials.
• Combusting with energy recovery.
• Landfilling
• Combusting without energy recovery.
Waste Management Hierarchy
Reducecleaner production
Reuseno reprocessing
Transformwaste to energy and treatment
Recyclereprocess to new goods
Disposelandfill
Reduce
• reduction of the amount and the toxicity of waste throughout “the design, manufacture, and packaging of products with minimum toxic content, minimum volume of material, or a longer useful life.” (Tchobanoglous, et al, 1993)
• concerns on many aspects such as the development of low-waste technologies, product recovery and reuse, the creation of product design for recycling, and the increase of the overall product life (Bilitewski, et al,1996).
Reduce (cont.)
• should be applied by both industries (e.g. by using recyclable material for packaging) and consumers (e.g. by buying reusable products) minimise the raw material consumption in production and waste generation in the end of product life (Rhyner, et al, 1995)
• How to reduce:– Implement cleaner production (next lecture)
Reuse
• “…findings another or similar use for product rather than discarding it (McBean, et al, 1995, p. 20)
• some applications of waste reuse (Tchobanoglous, et al. (1993):
1. direct reuse (e.g. wooden pallets, furniture), 2. raw materials for remanufacturing and reprocessing (e.g.
aluminium, plastics, glass, paper and cardboard), 3. feedstock for production of biological and conversion products
(e.g. yard wastes, organic fraction of MSW), 4. fuel source (e.g. waste oil, yard waste) and 5. land reclamation (e.g. construction and demolition waste)
Recycle
• “the separation and collection of waste materials; the preparation of these materials for reuse, reprocessing, and remanufacture; and the reuse, reprocessing, and remanufacture of these materials, such as recovery plastic containers for the secondary material market.” (Tchobanoglous, et al, 1993, p.16)
• Some environmental and economic benefits for industries (Rhyner, et al, 1995) : – energy and water saving, – material conservation, and – energy and pollution control cost saving.
Transform (waste to energy and treatment)
• involves the physical, chemical, or biological alterations of wastes which can be used “…to improve the efficiency of waste management; to recover reusable and recycle materials; and, more importantly, to recover conversion products (e.g. compost) and energy from the heat and combustible biogas.” (Tchobanoglous, et al, 1993, p. 16)
• Disadvantages (BCSE, 2005):– no further practical values for reusing, recycling or
reprocessing of the waste stream, – consumes much money and needs high technology.
Dispose (landfill)
• Is accepted as a common way to handling the waste problems in a community (Rhyner, et al, 1995).
• It is used if the wastes cannot be recycled or no further use (Tchobanoglous, et al. 1993).
Dispose (landfill) cont.
• Disadvantages for the environment (Bilitewski, et al, 1996 and Mendes, et al, 2003):– high emission of methane, a potent greenhouse gas; – risk of leachate leakage and consequent
contamination of water streams; – lack of landfill sites.” – cannot be used for the long term period – needs high cost to maintain.
Integrated Waste Management
• Involves using a combination of techniques and programs to manage the waste stream.
• Based on the fact that solid waste is made up of distinct components – recyclables and combustibles
Integrated Waste Management
Integrated waste management has been defined as the integration of waste streams, collection and treatment methods, environmental benefit, economic optimization and social acceptability into a practical system for any region (Warmer Bulletin 49, 1996).
Elements of an integrated
waste management
system?
Source: Waste Treatment & Disposal
The 6 components of an integrated
waste management
system
Source: Waste Treatment & Disposal
Implementation
• should recognize the rapid changes occurred in facilities, recovery of materials, and disposal options.
• should be based on their characteristics, environmental impacts, economics, and societal acceptability.
• varies among countries, societies or organizations.
Example
Figure 1 Waste Management in OEDC Countries (Zacarias-Farah and Geyer-Alle´ly, 2003)
References Australian Business Council for Sustainable Energy (BCSE). 2005. Waste to energy a
guide for local authorities. Victoria.
Bilitewski, B., G. Hardtle, K. Marek, A. Weissbach, and H. Boeddicker. (1996), Waste Management, Springer, Berlin.
McBean, E. A., F. A. Rovers, and G. J. Farquhar. (1995), Solid Waste Landfill Engineering and Design, Prentice Hall HTR, New Jersey.
Mendes, M. R., T. Aramaki, and Keisuke Hanaki. (2003). Assessment of the environmental impact of management measures for the biodegradable fraction of municipal solid waste in Sa˜ o Paulo City. Journal of Waste Management 23,403–409. Retrieved September 18, 2006, from http://www.elsevier.com/locate/wasman/html
Rhyner, C. R., L. J. Schwartz, R. B. Wenger, and M. G. Kohrell. (1995), Waste Management and Resource Recovery, Lewis Publishers, New York.
Tchobanoglous, G., H. Theisen, and S. Vigil. (1993), Integrated Solid Waste Management: Engineering Principles and Management Issues, McGraw-Hill, Inc, New York.
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