Chapter 16 Waste Generation and Waste Disposal

Chapter 16Waste Generation and

Waste Disposal

Ecological systems input: Plant materials, nutrients, water and energy (sun)

Human systems input: same as above but also other materials that are made by humans.

Waste is any non-useful products generated within a system.

How do we determine what is ‘useful?’ Detritivours take the waste produced

by other animals and use it as food or energy.

Humans use animal waste as fertilizer “One man’s trash is another mans

treasure.” Humans are the ONLY organism that

produces waste that others cannot use.

In 1900 the US recycled almost ALL: metal, wood and glass.

As a society becomes more wealthy they gradually generate more waste.

With the baby boom after WW II consumption patterns changed.

The creation of “one-time use” items and materials allowed for materials to be thrown away.

Only one problem… there is NO ‘AWAY’!

Refuse collected by municipalities from households, small businesses, and institutions such as schools, prisons, municipal buildings and hospitals.

60% comes from households

40% comes from commercial and institutional facilities

Municipal Solid Waste

By how many metric tons did MSW increase between 1960-2000?

Give two possible reasons for this increase.

How much more waste did a person who lived in 2010 generate compared with a person who lived in 1960?

Agricultural waste Mining waste Industrial waste MANY MORE!

These are normally processed on site and do not transfer waste to a new location for disposal.

US produces 2.2kg (4.8lbs) person/day Japan produces ~ 1.1kg (2.4 lbs)

person/day Most of the developing world produces

~ .55kg (1.2lbs) person/day Developed world rages from .8-2.2kg

(1.8-4.8lbs) Person/day What will happen to MSW in the

developing world? WHY?

Most products are made out of organic compounds, fibers and petroleum products.

Waste is generated during the manufacturing process, packaging and disposal.

Waste stream--refers to the flow of solid waste that is recycled, incinerated, placed in a solid waste landfill or disposed of in another way.

Identify a specific consumer product that is overly packaged: cell phone, gum, toy truck, etc…

Redesign it packaging so it generates less waste.

The US has established landfills in many developing countries

Impoverished people will try to scavenge waste from dumps.

Computer waste can be stripped of heavy metals

Composition of municipal solid waste—US

31% - paper 33%- organic

materials (yard waste, food scraps, wood)

12%- plastic 18%- durable goods

(appliances, tires)

Composition of Municipal Solid Waste

Electronic waste (E-waste) televisions, computers, cell phones that contain toxic metals.

E-Waste

Reduce- waste minimization or prevention

Reuse- reusing something like a disposable cup more than once

Recycle- materials are collected and converted into raw materials and then used to produce new objects

Reduce, Reuse, Recycle

Compost- organic material that has decomposed under controlled conditions to produce an organic-rich material.

Composting

Composting with worms Worms eat the leftover

food and turn it into nutrient rich soil.

Also called Humus Good compost has a pleasant

smell and enhances soil quality by adding nutrients to the soil.

(N,P,K) Most potting soil is ALL humus

(not always the best for plants) Loam= best soil, equal parts sand, silt and clay.

•Most waste ends up in a landfill

Sanitary landfills- engineered ground facilities designed to hold MSW with as little contamination of the surrounding environment as possible.

Leachate- the water that leaches through the solid waste and removes various chemical compounds with which it comes into contact.

Landfills

Input MUST be managed! No metals and no organic matter!

Plastic or clay lined Pipes below the ground collect leachate When a landfill reaches capacity it is

‘caped’ with soil and clay Water input is minimized because it

causes a greater rate of anaerobic digestion

Leachate is tested regularly for toxicity

The municipalituy pays for the construction and they make their $ back in Tipping fees

Tipping fee– cost per ton of waste dumped into the landfill. Average ~$35/ton

In some places is more if they have less space (NE US)

Lake Shore Drive Mt. Trashmore

What does MSW stand for? (1pt) What is waste? (1pt) What percentage of waste qualifies as organic

material? (1pt) What can be done to divert materials away from

the waste stream? (3pts) What is the difference between closed and open

loop recycling? (5pts) Draw and label a picture of a landfill (5pts) What are some of the components that need to

be controlled in a landfill? WHY?? (5pts)

More than ¾ of MSW can be burned. (paper, plastic, food and yard waste are carbon based so they can be burned)

Reduces the mass and volume of waste Sometimes the energy can be used for generation

of heat and electricity. When used for heat its called a ‘waste-to-energy’

system High efficient incinerators reduce 75% of the mass

and 90% of the volume of MSW On average ~ ¼ of the previous volume of MSW is

left.

Incineration•Ash is the leftovers from combustion •Bottom ash- what’s left in the furnace •Fly ash- Ash collected outside of the furnace

•Ash gets tested by running acidic water through it (leachate) to test for heavy metals, Lead and Cadmium.

•Safe ash gets used in construction, roads and bricks. •Toxic ash goes to a toxic dump.

Problems with Incineration

• Higher tipping fees ~$70/ton •NIMBY problems, location •Can release VOC’s and metals in exhaust •Ash tends to be more toxic •Need a large amount of MSW delivered daily in order to be efficient. •Communities are less likely to recycle.

Hazardous waste- liquid, solid, gaseous, or sludge waste material that is harmful to humans or ecosystems.

20,000 HW generators = 40 million tons of HW ~5% is recycled Most is the byproduct of industry: cleaning

machines, making computers. Small businesses- Dry cleaning, car repair, small

farms Households- oven cleaners , batteries and lawn

fertilizers.

Hazardous Waste (HW)

Collection sites for hazardous waste must be staffed with specially trained personnel.

Hazardous waste must be treated before disposal.

EPA – ‘less env. harmful’ Sending it through a series of chemical

reactions to neutralize it.

Resource Conservation and Recovery Act (RCRA)- designed to reduce or eliminate hazardous waste. Also know as “cradle-to-grave” tracking.

RCRA ensures that hazardous waste is tracked and properly disposed of.

Laws

Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA)- also know as “Superfund Act”.

Puts a tax on the chemical and petroleum industries. This revenue is used to cleanup abandoned and nonoperating hazardous waste sites where a responsible party cannot be found.

Requires the federal government to respond directly to the release of substance that may pose a threat to human health or the environment

Laws

Contaminated industrial or commercial sites that may require environmental cleanup before they can be redeveloped or expanded.

Old factories, industrial areas and waterfronts, dry cleaners, gas stations, landfills, and rail yards are some examples.

Brownfields

A method that seeks to develop as many options as possible, to reduce environmental harm and cost.

Reduction, recycling, composting, landfills, and incineration are some ways IWM is utilized.

Integrated Waste Management