摘要 |
<p>The invention relates to a method for fractionating a cracked gas flow in order to obtain an ethylene-rich cut and a fuel flow, and associated facility. Said method comprises injecting a downstream cracked gas flow (140) from a downstream heat exchanger (58) into a downstream separator (60) and recovering a high-pressure gaseous fuel flow (144) at the head of the downstream separator (60). The method comprises passing the flow (144) of fuel through the downstream exchanger (58) and an intermediate exchanger (50, 54) to form a reheated high-pressure fuel flow (146), expanding the reheated high-pressure fuel flow (146) in at least one first dynamic expansion device (68) and passing the flow (148) of partially expanded fuel from the intermediate exchanger (50, 54) into a second dynamic expansion device (70) in order to form an expanded fuel flow (152). The expanded fuel flow (152) from the second dynamic expansion device (70) is reheated in the downstream heat exchanger (58) and in the intermediate heat exchanger (50, 54).</p> |