A method generates superheated steam using heat generated in a boiler of an incineration plant. The pre-superheated steam is fed to a final superheater that includes a plurality of final superheater pipes through which the pre-superheated steam is guided and is finally superheated in the process. The final superheater pipes (are arranged at least partially in at least one cavity (formed in an interior of a wall element of the boiler and/or of a bulkhead arranged in the boiler. The cavity is closed off on a boiler side at least partially by a refractory material layer and is flowed over by flue gas released during combustion. A secondary medium flows through the cavity and is heated via heat transfer from the flue gas via the refractory material layer. The heated secondary medium is fed via a secondary medium feed line to a secondary heat exchanger.

A radiant heat recovery heater includes U-shaped heat transfer tubes each including a first path and a second path arranged on a mounting section. The U-shaped heat transfer tubes are housed in a container fixed to the mounting section. The first paths and the second paths of the U-shaped heat transfer tubes are arranged on the mounting section at equal intervals with a pitch angle . The first paths are each arranged on the mounting section at a position offset from the pitch angle for the associated second path by a predetermined angle , so as not to completely overlap a projection of that second path, the projection extending from the container toward the center C of the container.

An eFuels plant and process for producing synthetic hydrocarbons using renewable energy are disclosed. The eFuels plant comprises a hydrocarbon synthesis (HS) system and a renewable feed and carbon/energy recovery (RFCER) system. The RFCER comprises an oxygen-fired heater to provide operational flexibility and efficiency. The oxygen fired heater comprises: a) one or more burners, suitable for accepting feeds comprising a hydrocarbon stream, an oxygen stream, and a diluent gas stream and producing combustion products comprising heat, carbon dioxide, and water; b) a radiant section, comprising a firebox and a radiant coil within the firebox, wherein the firebox is suitable for accepting the combustion products, and the radiant coil absorbs a first portion of the heat to produce first cooled combustion products; c) a convection section, comprising a convection coil and a convection inter-tube space defined by the outer surface of the convection coil, wherein the convection inter-tube space is suitable for accepting the first cooled combustion products to produce second cooled combustion products; and d) a carbon dioxide recovery section, comprising a condensing coil and a condensing inter-tube space defined by the outer surface of the condensing coil, wherein the condensing inter-tube space is suitable for accepting the second cooled combustion products to produce third cooled products comprising a non-condensables stream, comprising carbon dioxide, and a water stream.

An eFuels plant and process for producing synthetic hydrocarbons using renewable energy are disclosed. The eFuels plant comprises a hydrocarbon synthesis (HS) system and a renewable feed and carbon/energy recovery (RFCER) system. The RFCER comprises an oxygen-fired heater to provide operational flexibility and efficiency. The oxygen fired heater comprises: a) one or more burners, suitable for accepting feeds comprising a hydrocarbon stream, an oxygen stream, and a diluent gas stream and producing combustion products comprising heat, carbon dioxide, and water; b) a radiant section, comprising a firebox and a radiant coil within the firebox, wherein the firebox is suitable for accepting the combustion products, and the radiant coil absorbs a first portion of the heat to produce first cooled combustion products; c) a convection section, comprising a convection coil and a convection inter-tube space defined by the outer surface of the convection coil, wherein the convection inter-tube space is suitable for accepting the first cooled combustion products to produce second cooled combustion products; and d) a carbon dioxide recovery section, comprising a condensing coil and a condensing inter-tube space defined by the outer surface of the condensing coil, wherein the condensing inter-tube space is suitable for accepting the second cooled combustion products to produce third cooled products comprising a non-condensables stream, comprising carbon dioxide, and a water stream.