Presentation on theme: "CH. 13. Solid-Waste Management 13.1. Introduction SOLID WASTE Definition Categories Examples Municipal solid waste (MSW) 70 % of MSW (valuable material."— Presentation transcript:
CH. 13. Solid-Waste Management 13.1. Introduction SOLID WASTE Definition Categories Examples Municipal solid waste (MSW) 70 % of MSW (valuable material such as glass, metal, and paper) could be recycled, however, only one-third of it was recycled in 2010, the rest was either incinerated or landfilled. In 2010, Americans generated 250 million tons of trash Waste disposal increased 1,350-1,606 lb/person/year in 1980-2010
Amount of MSW generated by typical families (in one week) around the world Japan, $317.25
If we are running out of space and contaminating our groundwater by burying our trash, and contaminating the air by burning our waste, What can we do? 1)Recycle paper, glass, and metal (pizza boxes are not recyclable!) 2)Compost organic waste at home 3)Consume less, 30% of our waste is composed of packaging! Compost Solid waste management in Ukraine A useful handbook for reducing solid waste. http://www.epa.gov/epawaste/wycd/catbook/index.htm
The objective of an Integrated Solid Waste Management is to avoid the use of landfill and incineration resources as much as possible as means of waste disposal. Thus, what it proposes is to reduce the amount of trash we generate by consuming as less as possible and reusing what we already own (or for instance visiting garage sales), and finding alternative programs such as recycling and composting. The final desired resource would be waste disposal such as incineration and landfill.
In the USA, the total amount of municipal solid waste generated increased from 88 million of tons in 1960 (2.6 pounds/person/day) to 250 million of tons in 2010 (4.4 pounds/person/day), however you can observe in the chart above, that in 2005, the generation of waste per capita, and thus the total amount of waste generated per year, leveled off. This shows that we are doing well watching the amount of waste we generate, but there still so much work to be done.
Inappropriate management of solid waste includes: Solid waste disposed in rivers reaches the ocean and finally concentrates along the beaches in Mumbai, India. Industrial waste (used engine oil) in a ditch in Male, Maldives contaminates the groundwater.
Potential disease transmission in a local grocery and meat market beside disposed waste in Haiti. Recycling Increased <10% in 1980 to 34% in 2010 A bicycle that recycles metal! http://www.fastcodesign.com/1671723 /a-safe-and-easy-way-to-mine-metals- from-e-waste
13.2.Solid waste characterization Typical percentage that makes up municipal solid waste (MSW). SourceExamplesCommentsTypical percentage of MSW ResidentialDetached homes, apartmentsFood wastes, yard/garden wastes, paper, plastic, glass, metal, household hazardous wastes 30-50% CommercialStores, restaurants, office buildings, motels, auto repair shops, small business Same as above but more variable from source to source. Small quantities of specific hazardous wastes. 30-50% InstitutionalSchools, hospitals, prisons, military bases, nursing homes Same as above; variable composition between sources. 2-5% Construction/ demolition Building construction or demolition sites, road construction sites Concrete, metal wood, asphalt, wallboard, and dirt predominate. Some hazardous wastes possible. 5-20% Municipal services Cleaning of streets, parks, and beaches; water and wastewater treatment grit and biosolids, leaf collection, disposal of abandoned cars and dead animals Waste sources vary among municipalities.1-10% IndustrialLight and heavy manufacturing, large food- processing plants, power plants, chemical plants Can produce large quantities of relatively homogeneous wastes. Can include ashes, sands, paper mill sludge, fruit pits, tank sludge. Not MSW AgriculturalCropping farms, dairies, feedlots, orchardsSpoiled food wastes, manures, unused plant matter (e.g., straw), hazardous chemicals Not MSW MiningCoal mining, uranium mining, metal mining, oil/gas exploration Can produce vast amounts of solid waste needing specialized management Not MSW
13.2.Solid waste characterization Quantities of generated and recovered waste in 2010. MaterialWeight generated (millions of tons) Weight recovered (millions of tons) Recovery as percent of generation (%) Paper and paperboard71.3144.5762.5 Glass11.533.1327.1 Metals Steel16.905.7133.8 Aluminum3.410.6819.9 Other nonferrous metals2.101.4870.5 Total metals22.417.8735.1 Plastics31.042.558.2 Rubber and leather7.781.1715.0 Textiles13.121.9715.0 Wood18.882.3014.5 Other materials4.791.4129.4 Total materials in products177.8664.9736.5 Other wastes Food, other34.760.972.8 Yard trimmings33.4019.2057.5 Miscellaneous inorganic wastes3.84negligible Total other wastes72.0020.1728.0 Total municipal solid waste249.8685.1434.1
13.2.Solid waste characterization Physico-chemical and biological characteristics. Density size distribution Moisture content Color, Odor, Shape, Optical properties Electric properties Magnetic properties Waste typeFungusProtozoaBacteriaInsectRodent Biomedical wasteXXXXX Food wasteXXXXX Hazardous waste Municipal solid waste XXXXX Radio active waste WEEEXX
13.2.Solid waste characterization Physico-chemical and biological characteristics. E. Coli contamination usually starts at slaughterhouses. Research conducted by Novotny et al. (2004) shows species of bacteria present in fish that are sources of human infections. These organisms are generally found in fish markets, floors, and fish boxes, specially during the summer.
13.2.Solid waste characterization
50% paints and paint products 20% used motor oil 20% solvents, pesticides and herbicides 10% batteries, unidentified materials and other miscellaneous items, such as old chemistry sets, photographic materials, and fiberglass epoxy.
13.3.Components of the solid-waste system Storage Collection Composting Landfill Residential Commercial Construction and demolition Institutional Municipal services Transfer station Materials recovery facility Incineration Recycled materials Compost
Storage Storage is the immediate stage after generation, or before final disposal or recycle/reuse. Storage duration depends on the collection process, which varies from once to twice per week. There are many designs for storing waste. The table below summarizes the most common containers for solid waste storage. Different categories of storage containers:
Storage Rubbish skip is used to transfer the waste to special vehicles or for door-to-door collection. Dumpsters are large steel containers used to transfer the waste to large transportation trucks. Municipal solid waste storage containers Solid waste is stored without safety precautions in many countries.
Storage Storage of hazardous materials There are various storage units such as containers, tanks, drip pads, waste piles, surface impoundments, or containment buildings designed to house chemicals, flammables, solvents, paint, explosives, and other hazardous materials. The storage of hazardous materials need to comply the regulatory requirements specified by RCRA (Resource Conservation and Recovery Act). Storage of hazardous materials in buildings. Federal regulations allow small quantity hazardous waste generators (100-1000kg) to store the waste for up to 270 days without permit. http://www.gpo.gov/fdsys/pkg/CFR-2012-title40-vol27/xml/CFR-2012-title40-vol27-part264.xml
Collection Side- and rear-end loading vehicles are commonly used for residential collection Front-end loading vehicles are commonly used for commercial collection
Collection Collection of solid waste in developing countries is more inefficient. Most of the budget is spent in collection and yet, they are not able to collect all the generated waste. Collection varies from household level (called primary), where waste is collected from individuals using bicycles, handcarts, private trucks, horses, etc. as medium of transportation and then put into community collection containers. The secondary collection system is then performed by the city council using small mechanical vehicles, trucks, and tractors. Solid waste management in Africa.
Collection Collection of solid waste in developing countries
Collection Collection of solid waste in developing countries http://www.swlf.ait.ac.th/Slide%20Show/Collection.pdf
Collection Collection of solid waste in developing countries
Street sweeping in developing countries Collection
Composting Biodegradable plastic containers are marketed as compostable, but they dont completely degrade and may in fact contaminate the compost. http://grist.org/food/is-your-cup-compostable-or-just-biodegrable-and-why-does-it-matter-again/
Composting systems perform best when the carbon-to-nitrogen ratio is in the range of 20-40 (C:N 20:1 to 40:1), which means that carbon content is 20-40 times larger than nitrogen. Table 13.11 in your textbook shows nutrient content of various materials used in composting. MaterialNitrogen (% dry mass)C:N ratio (dry mass basis) Potato tops1.525 Wheat straw0.3-0.5130-150 Fresh leaves0.5-1.041 Food wastes3.216 Mixed paper0.19230 Yard wastes2.023 Learn how to compost correctly: http://greenliving.nationalgeographic.com/compost-correctly-2358.html
Recycling Materials recovery facility. 1.Scale 2.Tipping floor 3.In-feed conveyor 4.Pre-sort 5.OCC screen 6.ONP screen 7.Glass breaker screen 8.Paper sorting 9.Commingle conveyor belt 10.Plastic sorting 11.Steel magnet 12.Optical sorter 13.Eddy current separator 14.Balers 15.Bale storage 16.Glass cleanup system 17.Glass bunker 18.Residue belt 19.Residue bunker 20.Outbound truck 21.Education center 22.Offices http://www.recommunity.com/interactive-mrf/
Landfill Landfill decomposition pathways: 1)Initial adjustment phase: Microorganisms adjust to the landfill conditions. 2)Transition phase: Transformation from aerobic to anaerobic environment. 3)Acid formation phase: Volatile organic acids are formed during biodegradation of organic waste. 4)Fermentation phase: Generation of carbon dioxide, hydrogen sulfides, methane, and ammonia due to microbial reactions of organic acids. 5)Maturation phase: Biodegradation stops or develops at lower rate. Leachate production is lower as well.
Landfill Typical anatomy of a landfill
Incineration Incineration, also called waste-to-energy, is one of the most widely used methods to dispose combustible waste by using high temperatures (800-1050 C) to convert waste into flash, flue gas, and heat. The process can be optimized by using waste with high energy content, low moisture, and low ash content. Advantages: Volume of waste is reduced (~80-85%) so landfills are avoided Water content in waste can be used as steam to heat systems or generate electricity Cost of transportation of municipal solid waste is reduced Disadvantages: High construction and operating costs. Fly ash and generated particles need to be eliminated from the resultant emissions before releasing to the air by air pollution control equipment Toxins such as dioxins, furans, mercury, volatile metals, nitrous oxides are also released during the combustion process and need to be eliminated before releasing to the air.
Incineration 2. Burning process. Temperatures range 800-1050 C. Initial volume of the waste is reduced 80-85% 1. Municipal solid waste. Includes paper, textiles, rubber, leather, wood, etc. 3. Steam formed inside the incinerator is recovered to fuel turbines to produce energy 5. The resultant gases are clean and follow federal air quality regulations. 4. Toxic compounds and particles are captured to ensure good quality of the released air 6. Ashes are recovered and disposed in landfills
How many times can something be recycled? http://earth911.com/news/2012/11/12/how-many-times-can-materials-be- recycled/paper-bales-our-flickr/ How much energy does recycling save? http://greenliving.nationalgeographic.com/much-energy-recycling-save-2363.html Recycling facts http://www.recyclingtown.com/ http://www.recycling-revolution.com/recycling-facts.html How to identify hazardous waste http://www.in.gov/idem/5043.htm#step3