THERMAL PYOIL TO A GAS FED CRACKER FURNACE
A predominantly C 2 to C 4 hydrocarbon cracker stream is combined with recycle content pyrolysis oil to form a combined cracker stream and the combined cracker stream is cracked in a cracker furnace to provide an olefin-containing effluent. The r-pyoil can be fed to a first coil while a second cracker feed with none of the r-pyoil or less of the r-pyoil is fed to a second coil, and both are cracked in a cracker furnace to form an olefin-containing effluent stream. Alternatively, the r-pyoil can be fed and distributed across multiple coils along with the non-recycle cracker feed. The furnace can be a gas fed furnace, or split cracker furnace. Further, a first cracker stream with r-pyoil in a first coil can have a lower total molar flow rate than a second cracker stream in a second coil in the same furnace.
1 . A method for making one or more olefins, said method comprising
(a) combining a predominantly C 2 to C 4 hydrocarbon cracker stream with a stream comprising a recycle content pyrolysis oil composition (r-pyoil) to form a combined cracker stream; and
(b) cracking said combined cracker stream in a cracker furnace to provide an olefin-containing effluent.
2 . The method of claim 1 , wherein the combined cracker stream is at least 95% vapor when introduced through a tube into a radiant section of the cracker furnace.
3 . The method of claim 1 , wherein the r-pyoil is introduced into coil inlets in the cracker furnace, and amount of r-pyoil introduced into each coil inlet is not separately regulated.
4 . The method of claim 3 , wherein said introducing includes introducing said r-pyoil into a common header connecting coil inlets.
5 . The method of claim 1 , wherein at least a portion of said r-pyoil is obtained from the pyrolysis of waste plastic.
6 . The method of claim 1 , wherein said combining occurs prior to a convection section of said furnace.
7 . The method of claim 1 , further comprising prior to said combining preheating at least a portion of said stream comprising r-pyoil to provide a preheated stream.
8 . The method of claim 1 , wherein said combined cracker stream has a cracking residence time of not more than 2 seconds.
9 . The method of claim 1 , wherein said combined cracker stream further comprises steam, wherein the steam-to-hydrocarbon ratio in said combined cracker stream is at least 0.20:1.
10 . A method for making olefins, said method comprising:
(a) heating a cracker stream in the convection section of a cracker furnace to form a heated cracker stream;
(b) injecting an atomized pyrolysis oil stream into the heated cracker stream to form a combined cracker stream in a cross-over zone of said cracker furnace; and
(c) cracking said combined cracker stream in a radiant section of said cracker furnace to form an olefin-containing effluent.
11 . The method of claim 10 , wherein said atomized feed stream further comprises at least one atomizing agent.
12 . The method of claim 10 , wherein said injecting is performed using at least one spray nozzle.
13 . A cracker stream comprising a gas phase and atomized liquid phase at least partially dispersed in said gas phase, wherein said gas phase comprises predominantly ethane and/or propane and said atomized liquid phase comprises a recycle content pyrolysis oil composition (r-pyoil).
14 . The cracker stream of claim 13 , wherein the cracker stream is 100% vapor within 1 second of introducing into the furnace.
15 . The cracker stream of claim 13 , wherein said cracker stream comprises predominantly non-recycled propane or ethane.