school energy&environment

Which waste

The waste we produce every day is defined Urban Solid Waste (USW) and includes whatever is discarded during our daily activities. All other waste is defined special waste, which includes waste produced by industrial activities, handcrafts, hospitals, etc.
In order to simplify waste management, USW is subdivided according to its composition, also known as the product fraction. There are six main categories: 1) recyclable materials (paper, plastic, glass, etc.); 2) compostable materials (kitchen leftovers, garden trimmings, etc.); 3) bulky materials (sofas, furniture, etc.); 4) durable goods, waste electrical and electronic equipment (computers, TV sets, refrigerators, etc.); 5) dangerous urban waste (batteries, drugs, car batteries, etc.); 6) residue (whatever is not classified in the previous categories). USW can be considered a kind of documentation regarding the use and life-styles of those who produce them. In fact the types of waste differ not only from one state to another but also within the same state (for example, waste produced by a town and by the countryside, or by different areas of the same town). If we analyse the average hypothetical rubbish bag of the Italians, we will discover that most of the waste produced, up to 40% of the total, consists of compostable materials. The other main component of our waste consists of recyclable materials (about 48%) subdivided according to the raw material they are made of: paper and cardboard paper (20-30%), glass (7-10%), plastic (10-14%), metals (4-6%), wood and textiles (5-7%). The remaining part consists of durable and dangerous waste.