| 摘要 |
<p>A method of separating domestic waste comprises the steps of shredding the waste, separating the shredded waste in a first wind sifter 2 into a heavy fraction and a light fraction which comprises mainly paper, plastics sheet and organic material, screening the light fraction so as to obtain a through-flow mainly comprising organic material and an overflow mainly comprising paper and plastics sheet, and separating the overflow in a second wind sifter 7 into a heavy fraction comprising mainly paper and a light fraction comprising mainly plastics sheet. To provide a clean plastics fraction suitable for re-use, the light fraction from the first wind sifter 2 is screened on a coarse screen 5 having a screen opening size smaller than the average dimension ofthe plastics sheet in the waste after shredding so that the throughflow mainly comprises organic material and smaller pieces of paper and the overflow comprises mainly plastics sheet and larger pieces of paper and cardboard, and, after separation of the overflow from the coarse screen in the second wind sifter 7 into a heavy fraction comprising mainly larger pieces of paper and cardboard and a light fraction comprising mainly plastics sheet contaminated with light paper, this light fraction from the second wind sifter is wetted and then cleaned in a plastics afterseparator so as to provide a first fraction which contains clean plastics sheet and a second fraction which contains wet paper fibres. To form a combustible fuel the heavy fraction from the first wind sifter is separated by screening into an inert fraction and a combustible fraction, and this combustible fraction is combined with the heavy fraction from the second wind sifter.</p> |
