Patent ID: 11927345
Assignee: XRG TECHNOLOGIES, LLC
Field: Chemical engineering (Chemistry)
Classification: CPC F  B | IPC B  F

Claim 0:
1. A device for reducing emissions of nitrogen oxides and for increasing heat transfer in a fired process heater, said fired process heater comprising a radiant section having a plurality of process tubes and a burner, said device comprising:
a fuel and flue gas entrainment unit positioned remote from the burner of the fired process heater, the entrainment unit comprising:
a fluid outlet, a fluid inlet, and a fluid flow path intermediate of said fluid inlet and said fluid outlet; said entrainment unit fluid outlet configured to attach to said fired process heater upstream of one or more convection tubes such that said entrainment unit fluid flow path is in fluid communication with said radiant section of said fired process heater;
an inlet section of reducing diameter, a mixing section of constant diameter, and an exit section of expanding diameter;
a fuel injector configured to issue fuel at subsonic, sonic, or supersonic velocity into said entrainment unit fluid flow path, wherein the fuel is entrained with flue gas from said radiant section of said fired process heater in said entrainment unit fluid flow path to form an entrained flue gas and fuel mixture, which flows through said entrainment unit fluid flow path to said radiant section of said fired process heater;

ductwork positioned remote from the burner of the fired process heater, the ductwork comprising a fluid outlet, a fluid inlet, and a fluid flow path intermediate of said fluid inlet and said fluid outlet; said ductwork fluid outlet connected to said entrainment unit fluid inlet such that said ductwork fluid flow path is in fluid communication with said entrainment unit flow path; said ductwork fluid inlet configured to attach to said fired process heater such that said ductwork fluid flow path is in fluid communication with the flue gas from said radiant section of said fired process heater; and
wherein the entrainment unit and the ductwork form a closed circuit regarding fluid flow from the radiant section of the fired process heater, through the ductwork fluid flow path, the entrainment unit fluid flow path, and back to the radiant section of the fired process heater.