Abstract: Aspects of the present invention relate to a shell-and-tube heat exchanger (101), a method of using said heat exchanger, and to a hydrocarbon cracking furnace system comprising said heat exchanger. The shell-and-tube heat exchanger comprises at least: a spiral baffle (7) arranged to provide a helical flow path through the shell body (103) and an outlet collector pipe (4) that supports the spiral baffle and that extends substantially coaxially within the shell body, wherein the outlet collector pipe is mounted to and passes through a second tubesheet (106) bordering the shell body (103) on one terminal end, and wherein the outlet collector pipe (4) is separated from a first tubesheet (105) on the opposing terminal end by a gap that allows a shell-side fluid (F2) to exit the shell body (103).

Abstract: A cracking furnace includes a pyrolysis tube 1 for carrying a flow of fluid, the pyrolysis tube including a radially inner body 3 and a radially outer wall 2 which together define an annular flow passage 5, wherein at least one of the radially inner body and the radially outer wall has a centre line which extends helically in a longitudinal direction of the pyrolysis tube, so as to promote rotation of the fluid as it flows along the pyrolysis tube.

Abstract: 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.

Abstract: 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.

Abstract: A cracking furnace comprises a pyrolysis tube 1 for carrying a flow of fluid, the pyrolysis tube comprising a radially inner body 3 and a radially outer wall 2 which together define an annular flow passage 5, wherein at least one of the radially inner body and the radially outer wall has a centre line which extends helically in a longitudinal direction of the pyrolysis tube, so as to promote rotation of the fluid as it flows along the pyrolysis tube.