A fired heater has two cells segregated by an insulative wall. A first plurality of burners are located in the first cell and a second plurality of burners are located in the second cell. A radiant tube extends from the first cell to the second cell for carrying a fluid material through the heater to heat the fluid material. The flow of fuel to the burners in either the first cell or the second cell can be terminated to accommodate lower heater duty when demand is lower.

Systems and methods are provided for performing a partial trip for an ethane steam cracker while reducing or minimizing ethane consumption in a ground flare system during the partial trip. In particular, a trip system is provided that reduces the firing on an ethylene furnace (such as a reduction into a range of 10% to 40% of normal firing) while also providing a reduced flow of feed to the furnace with dilution steam at a steam to hydrocarbon ratio similar to a ratio that is suitable during normal operation. The trip system can be actuated, for example, when the loss of circulating quench water to the water quench tower is detected.

The invention relates to hydrocarbon pyrolysis, to equipment and materials useful for hydrocarbon pyrolysis, to processes for carrying out hydrocarbon pyrolysis, and to the use of hydrocarbon pyrolysis for, e.g., hydrocarbon gas upgrading. The pyrolysis is carried out in a reactor which includes at least one thermal mass having an open frontal area 55%.

An ethylene plant including a cracking furnace for converting a hydrocarbon feedstock into a cracked gas stream, and a separation section to provide at least an ethylene-enriched product stream, a hydrogen-enriched fuel stream and a methane-enriched fuel stream from the cracked gas stream. A passage way is provided for feeding at least part of the hydrogen-enriched fuel from the separation section to a burner of the cracking furnace and/or a passage way for feeding at least part of the hydrogen-enriched fuel from the separation section to a burner of a waste heat recovery boiler of a combined cycle gas turbine power plant (CCGT). The CCGT includes a gas turbine, which CCGT is configured to generate electric power and/or to generate high pressure steam to drive a steam turbine forming part of a steam generation circuit of the ethylene plant.

The present disclosure relates to processes, methods, systems, and apparatus for steam cracking hydrocarbon in a pyrolysis furnace having a convection zone and a radiant zone. The convection zone includes three heat exchangers in series with a serpentine arrangement. A fluid source is disposed each heat exchanger to provide steam into the heat exchangers. The present disclosure further relates to a process of adjusting the stream flow rate for each fluid source to control operating conditions such as flue gas temperature, stack temperatures, and temperatures of other components of the furnace.

Processes and apparatuses for relocating a reforming process heater service into the convection section rely on combining a flue gas recycle quench stream with the radiant section off gases entering the convection section. The uniformity of mixing influences the effectiveness of that quench stream. The more effective the quench stream is, the lower the equipment size required to manage the recycle design.

Processes and systems for steam cracking hydrocarbon feeds. The process can include introducing a first hydrocarbon feed into radiant coil(s) disposed within a first segment of a firebox to produce a first steam cracker effluent having a first coil outlet temperature. A second hydrocarbon feed can be introduced into radiant coil(s) disposed within a second segment of the firebox to produce a second steam cracker effluent having a second coil outlet temperature. The first and second segments can each include one or more burners providing heat thereto. The burner(s) in each segment can be operated at substantially the same firing rate such that an amount of heat produced by each burner can be substantially the same. A feed rate of the first hydrocarbon feed can be controlled based, at least in part, on a composition of the first hydrocarbon feed and the first coil outlet temperature.

A steam cracking process for converting hydrocarbons into smaller hydrocarbons, particularly olefins, in a tube reactor comprising a convection section, a cross-over section, and a radiant section. The process includes heating the fluid mixture inside the tube to a temperature at the end of the convection section where significant cracking occurs in the cross-over section. The high convection section and cross-over section temperatures allow for lower tube wall temperature in the radiant section resulting in less coke deposition on the inner wall of the tube, and hence extended run-lengths between adjacent decoking sessions.

Cracking furnace system for converting a hydrocarbon feedstock into cracked gas comprising a convection section, a radiant section and a cooling section, wherein the convection section includes a plurality of convection banks, including a first high temperature coil, configured to receive and preheat hydrocarbon feedstock, wherein the radiant section includes a firebox comprising at least one radiant coil configured to heat up the feedstock to a temperature allowing a pyrolysis reaction, wherein the cooling section includes at least one transfer line exchanger.

Systems and methods are provided for performing ethane steam cracking at elevated coil inlet pressures and/or elevated coil outlet pressures in small diameter furnace coils. Instead of performing steam cracking of ethane at a coil outlet pressure of ?22 psig or less (?150 kPa-g or less), the steam cracking of ethane can be performed in small diameter furnace coils at a coil outlet pressure of 30 psig to 75 psig (?200 kPa-g to ?520 kPa-g), or 40 psig to 75 psig (?270 kPa-g to ?520 kPa-g). In order to achieve such higher coil outlet pressures, a correspondingly higher coil inlet pressure can also be used, such as a pressure of 45 psig (?310 kPa-g) or more, or 50 psig (?340 kPa-g) or more.