Science 101 Dec 2013 | Page 25

Food wastes, they are first mixed with garden wastes that are collected from farms, they are then shredded together and left to decompose for two or four weeks. After that, they are exposed to a high temperature ( generally above 70 degrees Celsius ), to increase the activity of bacteria; to help speed up the decomposition process. Also to kill certain microbes that do not survive a temperature that is higher than 70 degrees, it is left for around three to four months with regular turning to insure that the decomposition process is complete, before it could be used as soil conditioner. If these food wastes were left to decompose naturally, they release methane gas which has a strong negative impact on the environment, as it highly contributes to the process of global warming. The most important material to be recycled is plastic. Because of its strong negative impact on the environment , and since plastic has become one of the most useable materials nowadays. Generally, plastic is shredded together, then it is washed before it is melted and reshaped and reused as new plastic. The main purpose of recycling plastic is to decrease its life span, because plastic is one of the most dangerous forms of waste, since it is not decompose naturalistically. As for paper, it is divided into different qualities. Chemicals such as hydrogen peroxide are used on the paper to separate different fibers, they are then screened to filter items such as staples, paper clips, etc... After then, whitening agents are used on these fibers t o re m o v e ink remains, and whiten the paper. The paper is then heated to dry the water that was used for washing in the drying step, before running through a huge roller that re flattens the paper to be used again. About 20 cubic meters of disposable waste is produced in the AUC New Cairo Campus. The environmental services director at the AUC clarified that one cubic meter of waste is equal to 700 kilograms. Garbage is assembled twice a day and delivered to these outside entities. The idea of using separated waste was designed with the intention of helping development projects. 24