Science Man and His Environment/Solid Waste

Definition



 * Solid Waste : Any unwanted product which is not a liquid or gas

Composition
Solid waste composition varies greatly between countries. For a comparison of waste composition between OECD countries and Asian cities see this page.

Definition

 * Source reduction : Reducing the amount of waste generated

Methods
There are no list of specific methods for source reduction. Methods will need to be applied on a case-by-case basis.

Methods include:


 * Decreasing consumption


 * Changing processes to produce less waste


 * Redesigning products to make them easy to repair, resuse, or recycle


 * Designing products to last longer


 * Reduce packaging


 * Much of packaging is done simply to sell a product (advertising, marketing, money!)


 * To see examples of overpackaging go here and here.

Reuse

 * Reuse : Use a product again without destroying it

Example


 * Refillable glass bottles


 * They are just washed and refilled

Recycling

 * Recycling : Converting wastes into new products

Examples


 * Aluminum


 * Recycling aluminum use 95% less energy than making it from ore.


 * Paper


 * Paper accounts for a large percentage of solid waste, recycling reduces landfill space considerably.


 * Plastics


 * Almost all plastics are made from oil


 * Most plastics do not breakdown

Composting

 * Composting : Using soil microorganism to decompose organic matter


 * Especially useful for food wastes, especially at the household level





Incineration



 * Incineration : Controlled burning of solid waste

Pros


 * reduces volume


 * produces energy

Cons


 * produces air pollution


 * toxic ash

Landfills



 * Landfill : burying waste underground in a specially built site

Landfill includes:


 * A clay base


 * A plastic liner


 * Daily soil cover


 * Top clay layer (applied when landfill is full)

Two things landfills create:


 * Methane gas


 * Can create dangerous pockets


 * Can be recovered for use as fuel


 * A liquid called leachate


 * can get into groundwater


 * collected by a leachate collection system