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Solid and Hazardous Wastes

ملتقى مكافحة العدوى والتعقيم المركزي
موضوع مغلق
  #1  
قديم 03-15-2011, 01:57 AM
الصورة الرمزية الكفاح
 


الكفاح will become famous soon enoughالكفاح will become famous soon enough


Municipal Solid Waste (MSW)
Paper 35.2 %

Yard Trimmings 12.1%

Food Scraps 11.7%

Plastics 11.3%
Metals 8.0%
Rubber, leather, 7.4%
and Textiles Glass 5.3%
Wood 5.8%

Other 3.2%

Total 100%

Municipal Solid Waste (MSW)
Municipal Waste Collection and Disposal:
Town “dump” no longer legal.
PHS recommends collection twice weekly.
No longer feed un****ed garbage to pigs.
Prohibited dumping in water (river or sea).


Open Dumping (prohibited since 1976 by Federal Government).
Dumps support large rodent populations.
Promote vector breeding (cockroaches, flies and mosquitoes).
Contaminate adjacent surface or groundwater.
Leachatecontaining dissolved pollutantsruns off or seeps downward through soil.
Odors.
Affect neighboring property values. Created NYMBY
!
Municipal Solid Waste (MSW)
Treatment versus disposal(?)
Treatments (volume reduction methods):
Reclamation.
Reuse.
Recycling.
Composting.
Size reduction (grinding).
Incineration.

Municipal Solid Waste (MSW)
nTreatment versus disposal(?)
Sanitary landfilling – the only way to get “rid” of material once it becomes MSW?
Treatments reduce volume, but they don’t get rid of solid waste.
Ultimately, the waste has to go somewhere!
Into a landfill.
Space(?)
Current Waste Disposal Alternatives
Sanitary Landfill (in England called “controlled tipping”).
Solid Waste must be placed in a landfill in an approved manner.
A study should be completed before a prospective site is approved.
Is any groundwater in the area at risk of being contaminated? How to prevent?
Can surface water be protected?
How will access to the site by wild animal foragers be prevented?

Current Waste Disposal Alternatives
Sanitary Landfilling:
Placement of a liner.
Plumbing to collect leachate
Plumbing to collect gas.
Daily cells.
Cell 8-10 feet in depth.
Solid waste in cell compacted by heavy equipment as it is received.
Six (6) inches of soil cover over working cell at the end of each day.

Current Waste Disposal Alternatives
Sanitary Landfilling:
Each layer of cells is called a lift.
A landfill may have anywhere from 3-? Lifts.
Final cover is two feet.
Cost of disposing in a landfill.
Nationwide tipping fee is under $35.00 per ton.

Current Waste Disposal Alternatives
RCRA Subtitle D:
Federal mandate
All landfills install groundwater monitoring wells.
All landfills install methane detection systems.
New cells within a landfill must have a double liner.
A leachate collection system must be installed.

Current waste Disposal Alternatives
Three “Rs.”
Reduction.
Reuse.
Recycling

Current waste Disposal Alternatives
Source Reduction:
Best? Don’t produce waste in the first place.
A top priority for reducing Wastes at their source.
Estimated that it will reduce the waste stream by 5%.
Buy only the amount of product that will be used.
Buy product that uses minimal amount of packaging
Avoid single service packaging.

Current waste Disposal Alternatives
Source Reduction:
Industry plays an important role in:
Packaging,
Size and weight of product, and
Less Hazardous components for toxic ones.
Implementing a “pay as you throw” policy.
14-27% reduction in MSW discarded.
37-59% increase in recycling.

Current waste Disposal Alternatives
Reuse (or multiuse):
Coffee cup instead of a styrofoam throw away.
Cloth napkins instead of paper.
China instead of paper plates.
Use grass clipping for mulch instead of throwing the away.

Current waste Disposal Alternatives
Recycling (Also known as resource recovery):
In 2004, it was reported:
26.7% of MSW in United States was either recycled or composted.
Maine 49%.
Oregon 48.8%.
Minnesota 45.6%.
Iowa 41.7%.
California 40.2%

Recyling
Paper 35.2%
Metal 8.0%
Glass 5.3%
Yard trimmings 12.1%
Food Scraps 11.7%
Total 72.3%

Leaves only 27.7% to go to the landfill!

Current waste Disposal Alternatives
Resource Recovery:
Resource conservation – recycling reduces pressure on forest resources and extends the nation’s supply of nonrenewable mineral ones.
Energy conservation – recycling consumes 50-90% less energy than manufacturing the same item from virgin materials.

Current waste Disposal Alternatives
Resource Recovery:
Pollution abatement – Manufacturing products from secondary rather than virgin materials significantly reduces levels of pollution emissions.
For example, recycling scrap metal, as opposed to processing iron ore in a coke oven, reduces particulate emissions by 11 kg/metric ton and eliminates the mining wastes generated in extracting iron ore and coal.
Recycling aluminum has an even greater environmental impact – both air pollution and energy use are thereby cut 95%.

Current waste Disposal Alternatives
Resource Recovery:
EPA launched in 2002 a Resource Recovery Challenge (CC) to boost the national recycling rate to 35%.
Curbside collection.
Source separation.
Bottle bills.
Take-back programs.
Batteries.
Motor oil.
Tires.

Current waste Disposal Alternatives
Composting:
Twenty-one states have laws prohibiting the landfilling of yard wastes.
Yard wastes make up 23% of the U.S. urban waste stream.
Methods of converting wastes to compost.
Windrow.
In-vessel

Current waste Disposal Alternatives
Windrow technique:
Long rows of wastes are piled outdoors and mechanically turned periodically to aerate the mass.
Used when land is abundant and funding is scarce.
Takes long time to complete the process – 2 to 3 years for complete breakdown of the wastes.

Current waste Disposal Alternatives
In-vessel operations or processes:
Expensive.
Pumps mechanically aerate windrows (aerated static piles) hastening decay and eliminating the need for frequent turning.
Used when the available space is at a premium.

Current waste Disposal Alternatives
Four basic steps to composting:
1. Preparation - incoming wastes are shredded to a relatively uniform size; in most composting operations, nonbiodegradeable materials such as glass, metal, plastics, tires, and so on are separated from the compostable wastes. In some composting operation, sewage sludge or animal manures are added to the refuse at this point.

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2. Digestion – microbes naturally present in the waste material or special bacterial inoculants sprayed on the refuse are utilized to break down organic waste materials. While digestion may be either aerobic or anaerobic, aerobic systems are generally preferred due to shorter time periods and fewer odor problems. In aerobic decomposition, heat given off by microbial respiration raises the temperature in the windrows well above the 140oF necessary to kill fly eggs, weed seeds, or pathogenic organisms

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3. Curing – after digestion of simpler carbonaceous materials is complete, additional curing time is allowed to permit microbes to break down cellulose and lignin in the waste.

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4. Finishing – to produce an acceptable finished product, compost may be put through screens and grinders to remove nondigested materials and create a uniform appearance. Some composting facilities bag or package the finished product to facilitate marketing or distribution.

Current waste Disposal Alternatives
Waste Combustion:
Burning urban refuse at large municipal incinerators.
By the 1960s, 300 municipal incinerators.
Many have been closed down because of air pollution.
It was found that close to 20% of all particulates in large cities were coming from municipal incinerators.

Current waste Disposal Alternatives
Waste Combustion:
Waste-to-energy (WTE) plants.
Burn refuse reducing its volume by 80-90%.
GeSome problems with toxic air emissions.
What to do with the ash.
Is it toxic?
Health Concerns Associated with Improper Disposal of Solid Wastes
Leachate leakage and pollution of surface waters.
Organics, metals, pesticides, etc
Leachate leakage and pollution of groundwater.
Organics, metals, pesticides, etc
Harborage and breeding sites for rodents and other mammals.
Breeding sites for insects (mosquitoes, etc),
Odors.
Safety hazard (collapse of poorly developed cells entraps animals, etc.)
Fire hazard.
Landfill cleanliness (paper and debris spread to adjoining neighborhoods) Causes stress in nearby residents. Origin of NYMBY

Hazardous Wastes
The Love Canal Story:
Story starts in the mid 1890’s.
William T. Love constructed a canal intended to serve as a navigable power channel, connecting the Upper Niagara to the Niagara Escarpment about 7 miles downstream, bypassing the falls.
Intended to generate cheap power for industrialization.
Company went bankrupt after construction of the canal.
Canal left 3000 feet long, 10 feet deep, and 60 feet wide.

Hazardous Wastes
The Love Canal Story:
In 1942 Hooker Chemical Company received permission to dump chemical wastes into the canal.
Dumped wastes until 1952.
In 1947 Hooker purchase the canal.
In 1953 canal was full, topped with soil.
Area containing canal sold to Niagara School board for $1.00.
School built in 1957.
In 1978, Health Commissioner of NYS Proclaimed,
“the existence of a great and imminent peril to the health of the general public.”
Hazardous Wastes
What is hazardous Waste?
Characteristics of hazardous waste:
Toxic – wastes such as arsenic, heavy metals, or certain synthetic pesticides are capable of causing either acute or chronic health problems.

Hazardous Wastes
What is hazardous Waste?
Characteristics of hazardous waste:
Ignitable – organic solvents, oils, plasticizers, and paint wastes that are hazardous because they have a flashpoint less that 60 C (140 F) or because they tend to undergo spontaneous combustion. The resultant fires are dangerous not only because of heat and smoke, but also because they can disseminate toxic particles over a wide area.

Hazardous Wastes
What is “Hazardous” Waste?
Characteristics of hazardous waste:
Corrosive – Substances with a pH of 2 or less or 12.5 and above can eat away at standard container materials or living tissues through chemical action and are termed corrosive. Such wastes, which include acids, alkaline cleaning agents, and battery manufacturing residues, present a special threat to waste haulers who come into bodily contact with leaking containers.

Hazardous Wastes
What is hazardous Waste?
Characteristics of hazardous waste:
Reactive – obsolete munitions, wastes from the manufacturing of dynamite or fire*****ers, and certain chemical wastes such as picric acid are hazardous because of their tendency to react vigorously with air or water or to explode and generate toxic fumes.



Hazardous Wastes
Generation of hazardous Wastes:
Prior to 1980, 90% of all hazardous waste was being disposed of by methods that wouldn’t meet government standards.
Stringfellow in California.

Hazardous Wastes
Threats Posed by Careless Disposal:
Direct contact –
Fire and/or explosions –
Poison via the foodchain –
Air pollution –
Surface water contamination –
Groundwater contamination -

Hazardous Wastes
Methods of hazardous Waste Disposal:
Secure chemical Landfill.
Deep well injection.
Various chemical, physical, or biological treatment processes.
Waste exchanges.
Hazardous Wastes
Siting Problems: from “NIMBY” to “BANANA:”
Not In My Back Yard.
Build Absolutely Nothing Anywhere Near Anything!

Hazardous Waste Management Legislation: RCRA
1976 Congress passed the Resource Conservation and Recovery Act (RCRA).
1980 Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA).
Dubbed the “Superfund.”
1986 Superfund Amendments and Reauthorization Act (SARA).

Hazardous Wastes
Household Hazardous Wastes:

Average American household generates 20 pounds of household hazardous waste per year.
Includes: pesticides, paint and varnishes, brush cleaners, ammonia, toilet bowl cleaners, bleaches and disinfectants, oven cleaners, furniture polish, swimming pool cleaners, batteries, motor oil, outdated medicines and others

from environmental book.
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من مواضيعي : الكفاح
موضوع مغلق

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