Process for hydraulic conveying of polyolefin pellets

A process for hydraulic conveying of pellets of polyolefins comprising the steps of:

• (i) extruding molten polyolefin into strands and cutting the strands into pellets in an underwater pelletiser;
• (ii) withdrawing a first pellet suspension stream from the underwater pelletiser;
• (iii) concentrating the first pellet suspension stream in a first pellet separator thereby producing a concentrated pellet stream and a first water stream substantially free of pellets and passing the first water stream back to the underwater pelletiser;
• (iv) passing the concentrated pellet stream to a hydraulic conveying line through a first vessel and mixing it with water thereby producing a second pellet suspension stream;
• (v) withdrawing the second pellet suspension stream from the first vessel and passing it to a second pellet separator;
• (vi) separating the pellets from water in the second pellet separator thereby creating a second water stream and a dry pellet stream and passing the second water stream back to the first vessel;
• and (vii) optionally passing the dry pellet stream to a blender or to a classifier, characterised in that any one of (1) the first pellet suspension stream, (2) the second pellet suspension stream or (3) the dry pellet stream comprises an antiblock.