The present invention relates to the field of fluid heat transfer, and discloses a heat transfer enhancement pipe as well as a cracking furnace and an atmospheric and vacuum heating furnace including the same. The heat transfer enhancement pipe (1) includes a pipe body (10) of tubular shape having an inlet (100) for entering of a fluid and an outlet (101) for said fluid to flow out; the internal wall of the pipe body (10) is provided with a fin (11) protruding towards the interior of the pipe body (10), the fin (11) spirally extends in an axial direction of the pipe body (10), wherein at least one of a heat insulator (14) and a heat insulating layer (17) is provided at the outside of the pipe body (10). The heat transfer enhancement pipe can reduce thermal stress of itself, thereby increasing service life of the heat transfer enhancement pipe.

The present invention relates to the field of fluid heat transfer, and discloses a heat transfer enhancement pipe as well as a cracking furnace and an atmospheric and vacuum heating furnace including the same. The heat transfer enhancement pipe (1) includes a pipe body (10) of tubular shape having an inlet (100) for entering of a fluid and an outlet (101) for said fluid to flow out; internal wall of the pipe body (10) is provided with a fin (11) protruding towards interior of the pipe body (10), wherein the fin (11) has one or more fin sections extending spirally in the axial direction of the pipe body (10), and each fin section has a first end surface facing the inlet (100) and a second end surface facing the outlet (101), at least one of the first end surface and the second end surface of at least one of the rib sections is formed as a transition surface along spirally extending direction. The heat transfer enhancement pipe can reduce thermal stress of itself, thereby increasing service life of the heat transfer enhancement pipe.

Heat exchanger for quenching reaction gas comprising—a coolable double-wall tube including an inner tubular wall and an outer tubular wall, wherein said inner tubular wall is configured to convey said reaction gas to be quenched, and wherein a space defined by said inner tubular wall and said outer tubular wall is configured to convey a coolant; —a tubular connection member having a bifurcating longitudinal cross-section comprising an exterior wall section and an interior wall section defining an intermediate space filled with refractory filler material, wherein a converging end of said connection member is arranged to be in connection with an uncoolable reaction gas conveying pipe, wherein said exterior wall section is connected with said outer tubular wall of said coolable double-wall tube, wherein an axial gap is left between said interior wall section and said inner tubular wall of said coolable double-wall tube.

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.

A quenching system for a plant, operating a cracking furnace, works with liquid as well as gaseous starting materials. The quenching system includes a primary heat exchanger (PQE 10) and a secondary heat exchanger (SQE 11) and a tertiary heat exchanger. A TLX-D exchanger (TLX-D 26) is arranged and configured as the tertiary heat exchanger for dual operation. The TLX-D (26) is connected in series via a TLX-D gas feed line (24) to the SQE 11. The TLX-D (26) is connected to a steam drum (59), which is connected to a feed water line (49), via a TLX-D feed water drain line (34) and a TLX-D riser (46) and a TLX-D downcomer (38). The SQE 11 is connected to the steam drum (59), which is connected to the feed water line (49), via a TLX downcomer (52) and a TLX-riser (57).

Shell and tube apparatus (1) comprising: an outer shell (2); a first tube bundle (3) and a second tube bundle (4) coaxial with each other; a first inner shell (5) and a second inner shell (6); the first inner shell surrounds the first tube bundle and is arranged between said two tube bundles; the second inner shell surrounds the second tube bundle and is arranged in the space between said second tube bundle and the outer shell (2); the first tube bundle (3) operates as a preheater; the second tube bundle (4) operates as a boiler; the coaxial inner shells (5, 6) define a counterflow path for a hot fluid which passes through the shell side.

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.

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.

A box style steam methane reformer (15) has plural sections (37), with each section having walls (27-29-31, 33) forming an interior cavity (35) and open ends (43) that communicate with the interior cavity. Each section has a feedstock supply pipe (71) and a fuel supply pipe (63) located along the top wall, as well as a syngas collection pipe (79) and a flue gas collection duct (75) located outside of the bottom wall. The pipes and ducts have ends that are aligned with each other to allow the sections to be assembled together. Burners (67) are in the interior cavity and are connected to the fuel supply pipe. Reactor tubes (59) extend through the interior cavity. Refractory members (81) are located in the interior cavity and across a slot. The spacing between the refractory members varies to control the flow of flue gas.

The present invention relates to the field of fluid heat transfer, and discloses a heat transfer enhancement pipe as well as a cracking furnace and an atmospheric and vacuum heating furnace including the same. The heat transfer enhancement pipe (1) includes a pipe body (10) of tubular shape having an inlet (100) for entering of a fluid and an outlet (101) for said fluid to flow out; internal wall of the pipe body (10) is provided with a fin (11) protruding towards interior of the pipe body (10), the fin (11) spirally extends in an axial direction of the pipe body (10), wherein a height of the fin (11) gradually increases from one end in at least a part extension of the fin. The heat transfer enhancement pipe can reduce thermal stress of itself, thereby increasing service life of the heat transfer enhancement pipe.