Electrical cracking heater for heavy feeds to produce olefins

Abstract

Processes and systems for converting a hydrocarbon mixture to produce olefins including a first preheater, one or more separation systems, a secondary transferline exchanger, a thermal cracking heater, a primary transferline exchanger, and a flow line. The process includes preheating a hydrocarbon feed, separating the preheated hydrocarbon stream, heating the vaporized hydrocarbon, and heating the liquid hydrocarbon stream. The process includes cracking the heated hydrocarbon stream and the second vaporized hydrocarbon stream, feeding the cracked hydrocarbon product stream to a primary transferline exchanger, and feeding the cooled hydrocarbon product stream to the secondary transferline exchanger. The method for flexibly converting hydrocarbon feeds includes preheating a second hydrocarbon feed, bypassing a separation system, and heating and cracking the hydrocarbon stream, feeding the cracked hydrocarbon product stream to a primary transferline exchanger for quenching, and feeding the cooled hydrocarbon product stream to the secondary transferline exchanger to recover the hydrocarbon product stream.

What is claimed: 
     
         1 . A system for converting a hydrocarbon mixture to produce olefins, the system comprising:
 a first preheater configured for preheating a hydrocarbon feed and producing a preheated hydrocarbon stream;   one or more separation systems configured for receiving a preheated hydrocarbon stream and producing a vaporized hydrocarbon stream and a liquid hydrocarbon stream;   a secondary transfer line exchanger configured for transferring heat to the vaporized hydrocarbon stream from a cooled hydrocarbon product stream, producing a heated vaporized hydrocarbon stream and a hydrocarbon product stream;   a thermal cracking heater comprising a radiant zone configured for cracking the vaporized hydrocarbon stream and producing a cracked hydrocarbon product stream;   a primary transfer line exchanger configured for receiving the cracked hydrocarbon product stream, quenching the cracked hydrocarbon product stream, and recovering the cooled hydrocarbon product stream; and   a flow line configured for transferring the cooled hydrocarbon product stream to the secondary transfer line exchanger, the secondary transfer line exchanger producing the hydrocarbon product stream.   
     
     
         2 . The system of  claim 1 , wherein the one or more separation systems comprises a flash separation system, a Heavy Oil Processing Scheme separation system, or both. 
     
     
         3 . The system of  claim 2 , further comprising a bypass line for diverting the preheated hydrocarbon stream to the secondary transfer line exchanger, bypassing the one or more separation systems. 
     
     
         4 . The system of  claim 1 , further comprising a second preheater configured for preheating a dilution steam feed, producing a preheated dilution steam stream, the system further comprising a flow line configured for mixing at least a portion of the preheated dilution steam stream with the preheated hydrocarbon stream. 
     
     
         5 . The system of  claim 1 , further comprising a third preheater configured for heating the liquid hydrocarbon stream, producing a second heated hydrocarbon stream, the system further comprising a flow line configured for mixing the second heated hydrocarbon stream with the heated vaporized hydrocarbon stream. 
     
     
         6 . The system of  claim 5 , wherein the third preheater comprises multiple heat exchangers selected from the group consisting of heat exchangers in series, in parallel, or a combination thereof. 
     
     
         7 . The system of  claim 1 , wherein the secondary transfer line exchanger comprises multiple heat exchangers in series. 
     
     
         8 . The system of  claim 4 , further comprising a dilution steam bypass line configured to feed a portion of the preheated dilution steam stream to the vaporized hydrocarbon stream. 
     
     
         9 . The system of  claim 1 , wherein the thermal cracking heater is selected from the group consisting of an electric heater, a fuel-fired heater, or a combination thereof. 
     
     
         10 . The system of  claim 1 , wherein the first preheater is an electric heater. 
     
     
         11 . The system of  claim 4 , wherein the second preheater is an electric heater. 
     
     
         12 . The system of  claim 5 , wherein the third preheater is a steam heater. 
     
     
         13 . A process for converting a hydrocarbon mixture to produce olefins, the process comprising:
 preheating a hydrocarbon feed in a first preheater, producing a preheated hydrocarbon stream;   separating the preheated hydrocarbon stream in one or more separation systems, producing a vaporized hydrocarbon stream and a liquid hydrocarbon stream;   heating the vaporized hydrocarbon stream in a secondary transfer line exchanger, producing a heated hydrocarbon stream;   heating the liquid hydrocarbon stream using a third preheater, producing a second heated hydrocarbon stream;   cracking the heated hydrocarbon stream and the second heated hydrocarbon stream using a thermal cracking heater, producing a cracked hydrocarbon product stream; and   feeding the cracked hydrocarbon product stream to a primary transfer line exchanger for quenching the cracked hydrocarbon product stream and recovering a cooled hydrocarbon product stream; and   feeding the cooled hydrocarbon product stream to the secondary transfer line exchanger, producing a hydrocarbon product stream.   
     
     
         14 . The process of  claim 13 , further comprising preheating a dilution steam feed in a second preheater, producing a preheated dilution steam stream, and mixing at least a portion of the preheated dilution steam stream with the preheated hydrocarbon stream upstream of the one or more separation systems, producing a preheated vaporized hydrocarbon mixture stream. 
     
     
         15 . The process of  claim 14 , further comprising mixing a portion of the preheated dilution steam stream with the vaporized hydrocarbon stream. 
     
     
         16 . The process of  claim 14 , further comprising mixing the dilution steam feed with the hydrocarbon feed upstream of the first preheater. 
     
     
         17 . The process of  claim 15 , wherein the preheated dilution steam stream accounts for less than 90% of the preheated vaporized hydrocarbon mixture stream, the preheated hydrocarbon stream, and the preheated dilution steam stream. 
     
     
         18 . The process of  claim 13 , further comprising mixing the heated hydrocarbon stream and the second heated hydrocarbon stream downstream of the secondary transfer line exchanger and upstream of the thermal cracking heater. 
     
     
         19 . A method for flexibly converting hydrocarbon feeds to produce olefins, the method comprising:
 during a first time period:
 preheating a first hydrocarbon feed in a first preheater, producing a preheated hydrocarbon stream, wherein the first hydrocarbon feed comprises heavy hydrocarbons; 
 separating the preheated hydrocarbon stream in one or more separation systems, producing a vaporized hydrocarbon stream and a liquid hydrocarbon stream comprising the heavy hydrocarbons; 
 heating using a secondary transfer line exchanger the vaporized hydrocarbon stream using a cooled hydrocarbon product stream, producing a heated vaporized hydrocarbon stream and a hydrocarbon product stream; 
 heating the liquid hydrocarbon stream using a third preheater, producing a second heated hydrocarbon stream; 
 cracking the heated vaporized hydrocarbon stream and the second heated hydrocarbon stream using a thermal cracking heater comprising a radiant zone, producing a cracked hydrocarbon product stream; and 
 feeding the cracked hydrocarbon product stream to a primary transfer line exchanger for quenching the cracked hydrocarbon product stream and recovering a cooled hydrocarbon product stream; and 
 feeding the cooled hydrocarbon product stream to the secondary transfer line exchanger, recovering the hydrocarbon product stream; 
   during a second time period:
 preheating a second hydrocarbon feed in the first preheater, producing a vaporized hydrocarbon stream, wherein the second hydrocarbon feed comprises vaporizable hydrocarbons and no heavy hydrocarbons; 
 bypassing the separation system and heating using a secondary transfer line exchanger the vaporized hydrocarbon stream using a cooled hydrocarbon product stream, producing a heated vaporized hydrocarbon stream and a hydrocarbon product stream; 
 cracking the heated vaporized hydrocarbon stream using the thermal cracking heater, producing a cracked hydrocarbon product stream; and 
 feeding the cracked hydrocarbon product stream to a primary transfer line exchanger for quenching the cracked hydrocarbon product stream and recovering a cooled hydrocarbon product stream; and 
 feeding the cooled hydrocarbon product stream to the secondary transfer line exchanger, recovering the hydrocarbon product stream. 
   
     
     
         20 . The method of  claim 19 , further comprising preheating a dilution steam feed in a second preheater, producing a preheated dilution steam stream, and feeding at least a portion of the preheated dilution steam stream to the preheated hydrocarbon stream. 
     
     
         21 . The method of  claim 20 , further comprising controlling a separation system inlet temperature by one or more of:
 varying a duty of the first preheater;   varying a duty of the second preheater; and   varying a steam bypass ratio to control the flow of the preheated dilution steam stream to combine with the vaporized hydrocarbon stream flowing to the secondary transfer line exchanger.   
     
     
         22 . The method of  claim 21 , further comprising varying the steam bypass ratio by adjusting a valve position in a preheated dilution steam stream bypass line. 
     
     
         23 . The method of  claim 20 , wherein the preheated dilution steam stream accounts for less than 90% of a preheated hydrocarbon stream comprising a mixture of the preheated hydrocarbon stream and the preheated dilution steam stream.