A tube heat exchanger for exchanging heat from a first fluid to a second fluid, comprising a tubular shell ; an inner wall extending around a center axis of said tubular shell and forming a central chamber internally of said inner wall , and an annular heat exchange space extending externally of said inner wall and enclosed by said tubular shell , wherein the heat exchange space comprises a plurality of axially extending heat exchange sectors separated by radially extending separating walls , and flow paths of the first fluid and the second fluid extend in the heat exchange space, wherein adjacent heat exchange sectors communicate; a set of flow tubes extending axially in each of said heat exchange sectors in said heat exchange space; a first connection for inlet of the first fluid to a first set of flow tubes , and a second connection for outlet of said first fluid; at least one radially extending baffle dividing said heat exchange sectors into at least two axially displaced heat exchange segments, wherein the central chamber communicates with at least one opening in a tubeplate, and wherein a flow passage is provided between adjacent heat exchange segments to provide a flow path of the second fluid in a vertical direction between the adjacent heat exchange segments; a third connection for inlet of the second fluid to a first heat segment of a heat exchange sector, and a fourth connection for outlet of said second fluid; wherein a first flow path of said first fluid and a second flow path of said second fluid are divided to flow by a first portion clockwise and a second portion anti-clockwise through the axially extending heat exchange sectors , wherein a flow path of the second fluid extends radially in opposite directions in adjacent heat exchange segments in the heat exchange sectors , and a flow path of the first fluid extends perpendicular to the flow path of the second fluid. a tubular shell ; an inner wall extending around a center axis of said tubular shell and forming a central chamber internally of said inner wall , and an annular heat exchange space extending externally of said inner wall and enclosed by said tubular shell , wherein the heat exchange space comprises a plurality of axially extending heat exchange sectors separated by radially extending separating walls , and flow paths of the first fluid and the second fluid extend in the heat exchange space, wherein adjacent heat exchange sectors communicate; a set of flow tubes extending axially in each of said heat exchange sectors in said heat exchange space; a first connection for inlet of the first fluid to a first set of flow tubes , and a second connection for outlet of said first fluid; at least one radially extending baffle dividing said heat exchange sectors into at least two axially displaced heat exchange segments, wherein the central chamber communicates with at least one opening in a tubeplate, and wherein a flow passage is provided between adjacent heat exchange segments to provide a flow path of the second fluid in a vertical direction between the adjacent heat exchange segments; a third connection for inlet of the second fluid to a first heat segment of a heat exchange sector, and a fourth connection for outlet of said second fluid; wherein a first flow path of said first fluid and a second flow path of said second fluid are divided to flow by a first portion clockwise and a second portion anti-clockwise through the axially extending heat exchange sectors , wherein a flow path of the second fluid extends radially in opposite directions in adjacent heat exchange segments in the heat exchange sectors , and a flow path of the first fluid extends perpendicular to the flow path of the second fluid. <EOS>