20100243004 | Method and Apparatus for Washing Plastic Bottle Flakes Combining Batch- and Continuous-Mode Processing - This invention is a method and apparatus for optimizing equipment usage when recycling plastic flake. The apparatus is a hybrid arrangement of batch- and continuous-mode reactor vessels in which the flake and washing liquid are loaded in batches but discharged continuously. This is accomplished by placing a batch reactor of proper volume in front of a continuous reactor of proper volume in series. The batch reactor provides cleaning under controlled conditions, thereby ensuring each flake is washed for substantially the same time and in substantially the same manner. The solid-liquid slurry from the batch reactor is then discharged in batch mode into the continuous reactor. This continuous reactor acts as a surge tank, while at the same time providing additional scrubbing and discharging in a continuous fashion. The output of the continuous reactor is continuously discharged into a dewatering system. Given a desired discharge flow rate from the continuous tank to optimize downstream equipment operation, the size, loading, emptying and processing times of washing equipment can be calculated. | 09-30-2010 |