Chapter 16 Waste Generation and Waste Disposal

1. Chapter 16 Waste Generation and Waste Disposal

2. Systems and Waste • 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.

3. What is waste? • 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.

4. Society and waste • 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’!

7. Municipal Solid Waste • 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

8. Check for understanding • 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?

9. Other types of waste • 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.

10. US and the World • 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?

11. Content of the solid waste stream • 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.

12. Homework • Identify a specific consumer product that is overly packaged: cell phone, gum, toy truck, etc… • Redesign it packaging so it generates less waste.

13. Exported 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

14. Composition of municipal solid waste—US

15. Composition of Municipal Solid Waste • 31% - paper • 33%- organic materials (yard waste, food scraps, wood) • 12%- plastic • 18%- durable goods (appliances, tires)

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

17. Reduce, Reuse, Recycle • 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

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

21. Vermiculture • Composting with worms • Worms eat the leftover food and turn it into nutrient rich soil.

23. Compost Facts • 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.

24. Fate of MSW • Most waste ends up in a landfill

25. Landfills • 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.

26. Landfill Features • 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

28. Paying for landfills • 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)

29. Famous landfills • Lake Shore Drive • Mt. Trashmore

30. AP Quiz • 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)

31. Incineration • 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.

32. 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.

33. 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.

34. Hazardous Waste (HW) • 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.

35. Dealing with 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.

36. Laws • 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.

37. 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

38. Brownfields • 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.

39. Superfund sites

40. Integrated Waste Management • 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.