Fine separation device and separation method for olefin catalytic cracking products

The invention discloses a fine separation device and a separation method for olefin catalytic cracking products, and belongs to the field of chemical process. The separation device comprises a hexaneremoval apparatus arranged between a depropanization tower and a debutanization tower, wherein the hexane removal apparatus comprises a reboiler, a hexane removal tower, hexane removal tower bottom liquid cooling equipment, a hexane removal tower condenser, a hexane removal tower reflux tank and a reflux pump which are communicated with one another through pipelines. The invention also discloses aseparation method suitable for the fine separation device, and the method can realize fine separation of C6+ in olefin catalytic cracking byproducts in an OCC technology. According to the scheme, thefine separation device and the separation method can realize fine separation of C4 to C6+ components, complete conversion of economic added values of products from low to high, and facilitate high economic added value utilizat