Waste E.8.1 & E.8.2 Jessica Sachsenmaier

Methods of Waste Disposal Landfill Open dumping Ocean dumping Incineration Recycling

Landfill Advantages: -Efficient method to deal with large volumes -Filled land can be used for building or other community purposes Disadvantages: -Local residents may object to new sites. -once filled, needs time to settle, and may require maintenance as methane released

Open Dumping Advantages: -Inexpensive -Convenient (to the dumper) Disadvantages: -Causes air and ground water pollution -Health hazard: encourages rodents and insects -Unsightly

Ocean Dumping Advantages: -Source of nutrients -Convenient and inexpensive Disadvantages: -Danger to marine animals -Pollutes the sea

Incineration Advantages: -Reduces volume -Requires minimal space -Produces stable, odor-free residue -Can be used as a source of energy Disadvantages: -Expensive to build and operate -Can cause pollutants, e.g dioxins, if inefficiently burned -Requires energy

Recycling Advantages: -Provides a sustainable environment Disadvantages: -Expensive -Difficulty in separating different materials; not possible in all cases

Recycling of metal, glass, plastic and paper products Metals: – Mainly aluminium and steel. – Metals are sorted, then melted and either reused directly or added to the purification stage of metals formed from their ores. – Particularly important for metals such as aluminium, which require large amounts of energy to produce direct from ore.

Paper – Taken to the plant, sorted into grades. – Washed to remove inks etc., made into a slurry to form new types of paper, such as newspaper and toilet rolls.

Glass Sorted by color, washed, crushed, then melted and moulded into new products. Glass is not degraded during the recycling process, so can be recycled many times.

Plastics Industrial plastic is already sorted, but household waste plastic must first be sorted. Degraded to monomers by pyrolysis, hydrogenation, gasification and thermal cracking, then repolymerized. Fewer pollutants formed, and energy used to recycle rather than make from crude oil. Better to reuse than recycle.