A cracked gas cooling heat exchanger includes a tube connection between an uncooled tube (1) and a cooled tube (2), having a cooled inner tube (3) enclosed by a jacket tube (4), with a tube intermediate space (5) for flowing cooling medium. A gas inlet header (11) has a GI tube inner part (12) and a GI tube outer part (13) and a cooling space (14) with an insulating layer (15). The GI tube outer part connects via a water chamber (6) to the jacket tube. The GI tube inner part faces the inner tube and is connected on a face (8) of the water chamber. A weld backing ring (16), between an end face (9) of the cooling space and a bottom face (8) of the water chamber, is in the insulating layer of the cooling space, arranged in a turn-out/groove (17) in the insulating layer.

The present invention provides a thermal cracking tube having the effect of agitating a fluid in the tube and capable of preventing overheating due to the generation of laminar flow, wherein the thermal cracking tube 10 has an agitating element 20 formed on and projecting inwardly from an inner surface of the tube, wherein the fluid agitating element comprises a fin 21 extending along the inner surface of the tube and bumps 24 provided on a region near the fin and projecting inwardly from the inner surface of the tube, wherein the region near the fin includes an upstream side and/or a downstream side of the fin in the direction of the fluid flowing through the tube.

A tube for a steam cracking furnace comprising: at least one downstream tubular segment of circular section having a main diameter; at least one twisted tubular segment having a length less than a quarter of the length of the tube, and comprising: a central part with an elliptical or lobed section, having a helical pitch between one times and ten times the main diameter, and an aspect ratio of the elliptical or lobed section between 0.5 and 0.8; an upstream transition part establishing a geometric transition between the central part and a tubular segment of circular section; a downstream transition part establishing a geometric transition between the central part and the downstream tubular segment, with a fluid being intended to flow from the upstream transition part to the downstream transition part.

Conduits for cooling a hydrocarbon stream and processes for using same. The conduit can include a first inner wall defining a first bore, a second inner wall defining a second bore, and an outer wall disposed about the first and second inner walls. The conduit can also include an annular support wall connected to an inner surface of the outer wall. An end of the second inner wall and an end of the annular support wall can define a perimeter opening that can be in fluid communication with the second bore. An annular flexible ring can be bonded to the annular support wall and can flexibly contact the first inner wall. A substantially annular cavity can be disposed between the second inner and the outer walls and in fluid communication with the perimeter opening. A quench fluid introduction port can be configured to introduce a quench fluid into the cavity.

The present invention provides a thermal cracking tube formed with an agitating element that has a good agitation effect and improves heat transfer efficiency while minimizing an increase in the pressure loss of the fluid flowing through the cracking tube.

A thermal cracking tube 10 with an agitating element of the present invention is a thermal cracking tube having a tube axis with one end and the other end, wherein a fluid inlet is on the one end and a fluid outlet is on the other end, the tube being provided on an inner surface thereof with one or more fluid agitating elements 20 extending from the inner surface of the tube and having an inwardly facing top portion, wherein the agitating element is helically inclined to or is orthogonal to a longitudinal direction of the tube axis, and the top portion deviates to the fluid inlet side 11 or the fluid outlet side 12, relative to a center 0 of a width direction of the agitation element.

The present invention provides a method of cooling a regenerated catalyst and a device thereof, which employs low-line-speed operation, wherein a range of the superficial gas velocity is 0.005-0.7 m/s, wherein at least one fluidization wind distributor is provided, wherein the main fluidization wind enters the dense bed layer of the catalyst cooler from the distributor, and the heat removal load of the catalyst cooler and/or the temperature of the cold catalyst is controlled by adjusting the fluidization wind quantity. The method and a device thereof of the present invention has an extensive application range, and can be extensively used for various fluid catalytic cracking processes, including heavy oil catalytic cracking, wax oil catalytic cracking, light hydrocarbon catalytic conversion and the like, or used for other gas-solid fluidization reaction charring processes, including residual oil pretreating, methanol to olefin, methanol to aromatics, fluid coking, flexicoking and the like.

The present disclosure provides for thick fins on the surface of coils or tubes in a steam cracking furnace. The fins have a thickness at their base from ¼ to ¾ of the radius of the furnace tube. The fins have grooves or protuberances on not less than about 10% of a major surface. The fins help increase the radiant heat taken up by the tube from the walls and combustion gases in the furnace.

An apparatus is provided for processing reusable fuel comprising a first-type cyclone cooler having a first configuration. The apparatus also provides one or more second-type cyclone coolers, wherein each one or more second-type cyclone coolers has a substantially identical second configuration to respective other one or more second-type cyclone coolers, wherein the second configuration is different than the first configuration. The apparatus may also provide an air cooled heat exchanger, a coil condenser and one or more bubblers. The first-type cyclone cooler and the one or more second-type cyclone coolers are connected. One of the one or more second-type cyclone coolers is connected to the air cooled heat exchanger. The air cooled heat exchanger is connected to the coil condenser. The coil condenser is connected to the one or more bubblers.

A double-tube heat exchanger includes an outer tube and an inner tube forming a first annular gap. The outer tube is provided with an inlet connection and an outlet connection for inletting and outletting a first fluid flowing in the first annular gap. The inner tube includes a first inlet connection and a second outlet connection for inletting and outletting a second fluid flowing in the inner tube for an indirect heat exchange with the first fluid. One of the tube sections is integrally formed with an assembly wall which joints a first end of the outer tube to the inner tube, to seal the first annular gap at the first end of the outer tube. A second annular gap is exposed to the air and is in fluid communication neither with the first annular gap nor with the inner tube, and is partially surrounded by the first annular gap.

Tube-bundle heat exchangers are commonly used to quench reacting fluids to drop the temperature of the reacting fluid below a specific temperature which cuts off undesirable chemical reactions in a minimal time as practical. A common commercial application is production of olefins. Shell and tube type and bundles of tube in tube exchanges are used in this application, the method is applicable to both. Significant variations in reacting fluid mass flow rates in the tubes of the tube-bundle can cause sub-optimal performance of the process. By placement of precise partial obstruction to flow of the reacting fluids at the tube exits to an outlet plenum chamber, these flow variations can be controlled. By adding remotely readable temperature measurement, and making the obstructions adjustable, the operator of the production facility can minimize production losses due to the variations in flow between tubes in the tube-bundle.