Method and system for improving spatial efficiency of a furnace system

1. A furnace system comprising:

at least one lower radiant section comprising a first firebox disposed therein;

at least one upper radiant section disposed above the at least one lower radiant section, the at least one upper radiant section comprising a second firebox disposed therein, the at least one upper radiant section and the at least one lower radiant section being controlled independently from each other;

at least one convection section disposed above the at least one upper radiant section and fluidly coupled to the upper radiant section and the lower radiant section; and

an exhaust corridor defined by the first firebox, the second firebox, and the at least one convection section.

2. The furnace system of claim 1 , wherein the at least one convection section is offset from the at least one upper radiant section and the at least one lower radiant section.

3. The furnace system of claim 1 , wherein the at least one convection section comprises a convection inlet and a convection outlet.

4. The furnace system of claim 3 , wherein the convection inlet receives a residual oil feed.

5. The furnace system of claim 3 , wherein the at least one lower radiant section comprises a first radiant inlet and a first radiant outlet.

6. The furnace system of claim 5 , wherein the at least one upper radiant section comprises a second radiant inlet and a second radiant outlet.

7. The furnace system of claim 6 , wherein the convection outlet is fluidly coupled to the first radiant inlet and the second radiant inlet.

8. The furnace system of claim 6 , wherein the first radiant outlet and the second radiant outlet are fluidly coupled to a coke drum.

9. A method for reducing an area required for construction of a furnace system, the method comprising:

constructing at least one lower radiant section;

constructing at least one upper radiant section;

arranging the at least one upper radiant section above the at least one lower radiant section;

arranging a convection section above the at least one upper radiant section and fluidly coupling the convection section to the upper radiant section and the lower radiant section; and

softening a flux profile of the at least one upper radiant section via flue gasses exhausted from the at least one lower radiant section.

10. The method of claim 9 , wherein the at least one convection section is offset from the at least one upper radiant section and the at least one lower radiant section.

11. The method of claim 9 , comprising receiving a residual oil feed into the at least one convection section.

12. The method of claim 11 , comprising pre-heating the residual oil feed in the at least one convection section.

13. The method of claim 11 , comprising transferring the residual oil feed from the at least one convection section to the at least one lower radiant section and the at least one upper radiant section.

14. The method of claim 11 , wherein a first temperature of the residual oil feed, measured at an outlet of the at least one lower radiant section is substantially equal to a second temperature of the residual oil feed measured at an outlet of the at least one upper radiant section.

15. The method of claim 9 , comprising controlling the at least one lower radiant section independent of the at least one upper radiant section.

16. The method of claim 9 , comprising providing convective heating to the at least one convection section via flue gasses exhausted from the at least one lower radiant section and the at least one upper radiant section.

17. The method of claim 9 , comprising discharging a residual oil feed from the at least one lower radiant section and the at least one upper radiant section to a coke drum.