Chapter 16

Municipal Solid Waste: Disposal and Recovery

Chapter Introduction

Danehy Park- Cambridge, MA

Danehy Park 50-acre park opened in 1990. Built on a former city dump. Light system in the restrooms to warn of

evacuation in the case of methane buildup. Many dumps since the “solid-waste crisis”

of 1970s and 80s have been converted to parks, golf courses, and nature preserves.

The Ideal: When looking for sustainable

solutions, the ideal would be to imitate the natural world and reuse everything.

The Solid-Waste Problem

Lesson 18.1

MSW MSW=Municipal Solid Wastes

The total of all materials from homes or commercial establishments thrown away and collected by local governments.

Commonly called trash, refuse, or garbage.

Types of Waste: Hazardous: made up of the HAZMAT

materials: ignitable, corrosive, reactive, or toxic.

Industrial: 7.6 billion tons generated annually. Composed of demolition and construction waste, agricultural and mining residue, combustion ash, sewage treatment sludge.

Factors Contributing to Increasing Amounts of MSW

The Story of Stuff:21 minutes

Factors Contributing to Increasing Amounts of MSW

In part by: Increasing populations More so by: Changing lifestyles,

increased use of disposable materials*, excessive packaging*

* = two largest contributors to waste volume

Compare the procedures: 1960 the nation generated 2.7 pounds of MSW per person

per day. Most was combusted in open landfills to reduce volume. Produced clouds of smoke, bad smell, and breeding ground for rats and flies.

Some cities turned to incinerators (combustion facilities). Produced large amounts of air pollution when not monitored correctly.

Open dumps turned to landfills. 2003 the nation generated 4.5 pounds per person per day.

MSW Patterns of Disposal US 1998: 55% disposed in landfills, 28%

recovered for recycling and composting, 17% combusted.

US 2003: 55.4% landfills, 30.6% recycling, 14% combustion.

Over the past 10 years, the overall trend is landfill and combustion declining, recycling increasing. Pattern not the same for highly populated areas like

Japan (combusts 75%) and Western Europe (0ver 50%).

US: MSW Components

**However the proportions can vary depending on the season, the affluence or the generator (commercial vs. home).

The US Fate of MSW

In countries with large populations like Japan, these numbers change toward the direction of combustion…Japan combusts 80% of its MSW.

Who is in Charge?

Customarily the local jurisdictions have been in charge of waste collection. Own their own trucks. OR contracted out.

The cost is traditionally passed along to home owners via taxes or a PAYT system.

Landfills: waste put on or in the ground and covered with earth.

Problems with old landfill structures. Leachate generation Methane production Incomplete

decomposition Settling

Leachate Generation As water percolates through the refuse

and ground, it carries contaminates with it to ground water. Florida: Superfund helped to get

landfills state-of-the-art liners to prevent ground water contamination

Much of the land is flat, only a few feet above sea level and rests on water-saturated limestone…big problem.

Methane Production Natural Decomposition. Buried wastes are anaerobicaly

broken down by detritus feeders creating biogas. Gases seeping to the surface kill

vegetation, leading to erosion that exposes the unsightly wastes.

Biogas Exploitation 390 commercial landfill gas

facilities in the US California has the largest facility 1998: produced 108 trillion BTU’s

of energy=20 million barrels of oil. 2005: produced 9 billion kWh of

electricity.

Riverview, Michigan The city collaborates with DTE to

“mine” the landfill gas under the 212-acre landfill (Mt. Trashmore).

Provides 3700 homes with energy. Doubles as a ski and recreation area

during winter months.

Incomplete decomposition Materials don’t completely break down.

Paper makes up 35% of the MSW. If paper is recycled, it won’t become MSW.Research out of the University of Arizona has

shown that even materials previously thought to be biodegradable are often degraded at a very slow rate.

30 year old papers have been recovered (readable).

Why do the papers not break down? Not enough moisture. The problem?

If you add more water to the landfills (which will make the papers degrade faster), more toxic leachate is produced.

Archer Daniels Midland As oil prices rise, agricultural giant Midland,

has created biodegradable plastics made of PHA (polyhydroxylalkanoate) based on corn sugars.

The growth rate of these products is expected to increase by 20% per year based upon two things.1. High oil price

2. Demand for environmentally friendly packaging.

Settling Buildings not built on landfills

because of settling. Causes a problem for playgrounds,

golf courses that are converted landfills because it creates shallow depressions (or even deep holes) that hold water and seeps into ground water.

EPA: Improving Landfills EPA has upgraded siting and

construction regulations. Sited on high ground. Floor contoured. Layering of materials, leachate

draining system, and liners. Ground water monitoring.

Siting: Public Reactions

LULU (locally unwanted landuse)

NIMBY (not in my backyard)

NIMTOO (not in my term of office)

Siting Problems Drives up the cost of waste disposal. Leads to inefficient and equally

objectionable practice of long-distance transfer. Table 18-1 p 470.

A positive of the landfill siting problem is that it encourages people to reduce their amount of MSW and recycle

Advantages of Combustion: waste to energy Can reduce weight by 70% and volume by

90%. Toxic/hazardous materials concentrated into

two streams for easier handling and control. Generate electricity. No changes needed for collection procedures. 2/3 of combustion facilities are WTE facilities

(compliant with clean air act regulations). Resource recovery.

Combustion: Drawbacks Health affects: older, poorer managed

facilities. Expensive to build. Ash loaded with heavy metals. Must have continuing supply of

MSW. Impedes recycling (direct competition

for same materials).

Waste to Energy facility (Figure 18-7 page 471)

Steps to process p.471, #ed.

Cost of MSW disposal Tipping fees: $30-$100 per ton. Transportation costs.

Increasing expense has lead to illegal dumping.

Solutions

Lesson 18.2

The Solutions

Reduction Recycling Reusing Composting

Source Reduction Definition: practice of designing,

manufacturing, purchasing, or using materials in ways that reduce the amount or toxicity of the trash collected.

Accomplishes waste prevention EPA measures it by the amount of consumer

spending. Accomplishes two goals:

Reduces amount of waste to be managed. Conserves resources.

Source Reduction in Action Lightening the weight of many items has

reduced the amount of materials used. Electronic communication lessens paper

load. Durable goods made reusable. Lengthening product life. Get off the bulk mail list Begin composting

Recycling as a Solution More than 75% MSW is recyclable. Primary recycling: original waste

material made back into same product. News papers to newsprint

Secondary recycling: waste made into a new product. Newspaper to cardboard

How does recycling help? Recycle steel saves 2500 lbs of iron ore,

1000 lbs of coal and more than 5400 BTU’s of energy

One ton of paper saves 17 trees, 6953 gallons of water, 463 gallons of oil and 4000 kWh of energy.

Recycling paper decreases air pollution by 74%, and water pollution by 35%

Recyclable Materials Paper and paperboard

(48%)- recycled paper or insulation.

Most glass (19%)- new bottles or fiber glass.

Some forms of plastics (5.2%)- carpet fiber, outdoor apparel, building materials.

Metals (22%)- saves energy, creates jobs, and reduces trade deficit.

Yard wastes (56%)- humus

Textiles (14.4%)- strengthen recycled paper products.

Old tires (36%)- asphalt

Recyclable material (% recovery)-product it is made in to.

The Most Successful Recycling Programs No cost to recycle but PAYT for MSW Mandates Make it curbside Goals are ambitious but clear and

feasible Efforts made to involve industry Municipality has hired a recycling

coordinator

How popular is recycling? Virtually every state has specific recycling

goals. EPA reports state that in 1960 only 6.7% MSW

was recycled as compared to the 30.6% in 2003. Mostly driven by economic savings and

environmental concern. All of the recycling is highly promotes by the

Global Recycling Network.

“Experience has shown that at least two-thirds of households will recycle if presented with a curbside pickup program”

Critics of Recycling Generally base their argument on economics.

If the costs of recycling are compared to the cost of combustion or landfills, recycling generally comes in second best. Market for recyclable materials fluctuate greatly. The shortfall between cost and market value is generally

between $20-$135.

Garbage collection is a big business and those involved see recycling as cutting into their market.

International paper trade: The market for recycled paper has fluctuated

greatly over the years. 1980’s- market saturated and municipalities

had to pay to get rid of it. 1995-paper was so valuable is was bought at

about $160 a ton. Forest-poor countries like Europe and Asia

purchase paper from the US and other industrialized countries in the N hemisphere.

Fact:

A one meter stack of newspapers is equal to the amount of pulp from one tree.

Glass recycling: 5.3% enter the solid waste stream. 50% non burnable portion. Large portion of the roadside litter.

Injuries, flat tires, pollution created to mine and manufacture.

Not al the cost shows in the price of the item, some appears in taxes to clean up the litter, as well as injuries, flat tire repair, environmental degradation…

Bottle Laws: Environmental and consumer groups

have set some laws to promote recycling and reuse of beverage containers.

The opposition comes from beverage and container industries who say that bottle laws result in loss of jobs and higher beverage costs for the consumer.

Bottle Laws Continued: 11 states as of 2006 have adopted some type of

bottle law. The experience has been positive, proving the

beverage companies wrong by providing more jobs and costs have not risen, higher percentage of bottles are being recycled and a marked reduction in bottle litter.

In 2003 22% glass, 44% aluminum, 60% steel, 25% plastic bottles were recovered.

Bottle laws continued: Only two states have bottle laws with

regard to non returnables such as water and other non-carbonated drinks.

With the rising cost of petroleum and the many uses of plastic bottles, recycling them makes both economic and environmental sense.

Plastic Recycling Code 2: HDPE-high density polyethylene. Code 1: PETE-polyethylene terephthalate.

Use for recycled plastics is limited somewhat because of contamination in the cross over process. Ex: some may not be reused for food containers.

MRF’s- “murfs” Materials recovery facilities. 2001 there were 480 operating in the US. Wastes are sorted and shipped to proper

locations for reuse. Advantages:

Economy of sale High quality end products

Mixed waste facilities: Receives waste as if it were going to a

landfill or combustion facility. Waste put on a conveyer and is sorted

for recyclables before sending it to the landfill. 43 facilities in the US in 2001.

Public Policy and Waste Management

Lesson 18.3

MSW Regulations Solid waste disposal act 1965 Resource recovery act 1970 and1976 Superfund act 1980 Hazardous and solid waste

amendments 1984

Integrated Waste Management Different combinations of source

reduction, WTE combustion, recycling, recovery facilities, landfills, and composting depending on the options that work best for the region.

A system of several alternatives in operation at the same time.

Reduce, Reuse, Recycle Recycling is the wave of the future.

Should not be the main pursuant in lieu of reduction or reuse

Reduction is the most environmental sound. Wastes that are not generated do not

need to be managed.

Sustainable MSW Management

Waste reduction Safe waste disposal Recycling and reuse

Leachate Residues of decomposing organic

matter combined with iron, mercury, lead zinc, and other metals from rusting cans, discarded batteries, and appliances, paints, pesticides, cleaning fluids, news inks, and other chemicals.