Heat recovery steam generator with parallel tube bundles

Abstract

The disclosure concerns a heat exchanger, and in particular a waste heat recovery unit used to generate steam. In particular, the heat exchanger is provided with two or more separate tube bundles, each tube bundle being arranged in a separate section of a shell. An additional separate by-pass section is arranged in the middle of the shell. A first heat exchanging fluid, in particular a waste heat fluid, flows through the shell and is distributed between the separate sections of the shell and a second heat exchanging fluid, in particular water, flows through each tube bundle and exchanges heat with the first heat exchanging fluid. Alternatively, at least one tube bundle is flown by a different heat exchanging fluid.

1 . A heat exchanger, comprising:
 a shell defining an internal room, an inlet for a first heat exchange fluid, and an outlet for the first heat exchange fluid,   the internal room comprising: at least one wall dividing said internal room into separate sections,   the separate sections including at least one first heat exchange section and at least one second heat exchange section,   the first heat exchange section having a first heat exchange section inlet for the first heat exchange fluid and a first heat exchange section outlet for the first heat exchange fluid, and   the second heat exchange section-having a second heat exchange section inlet for the first heat exchange fluid and a second heat exchange section outlet for the first heat exchange fluid,   wherein at least one first tube bundle is arranged inside the first heat exchange section and at least one second tube bundle is arranged inside the second heat exchange section,   the first tube bundle having a first tube bundle inlet and a first tube bundle outlet and the second tube bundle having a second tube bundle inlet and a second tube bundle outlet,   the first tube bundle inlet being connected to a first feed line of a second heat exchange fluid and the second tube bundle inlet being connected to a second feed line of the second or a further heat exchange fluid,   at least one additional separate section being arranged inside said internal room, in between said first heat exchange section and said second heat exchange section,   the additional separate section having an additional separate section inlet for the first heat exchange fluid and an additional separate section outlet for the first heat exchange fluid,   the additional separate section being a first heat exchange fluid bypass section, wherein each heat exchange section is provided with respective flow regulating means.   
     
     
         2 . The heat exchanger according to  claim 1 , wherein the flow regu-lating means of each heat exchange section are independent from the flow regulating means of the other heat exchange sections. 
     
     
         3 . The heat exchanger according to  claim 1 , wherein the first heat exchange fluid is a heating fluid. 
     
     
         4 . The heat exchanger according to  claim 3 , wherein the heating fluid is an exhaust gas. 
     
     
         5 . The heat exchanger according to  claim 3 , wherein the second and any further heat exchange fluid is a fluid to be heated. 
     
     
         6 . The heat exchanger according to  claim 5 , wherein the fluid to be heated is water, oil or an organic fluid. 
     
     
         7 . The heat exchanger according to  claim 6 , wherein the fluid to be heated of said first feed line is different from the fluid to be heated of said second feed line is water, oil or an organic fluid. 
     
     
         8 . The heat exchanger according to  claim 5 , wherein the fluid to be heated of said first feed line and the fluid to be heated of said second feed line is the same fluid, said first feed line and said second feed line being arranged in parallel. 
     
     
         9 . The heat exchanger according to  claim 1 , wherein each thermal exchange section can be isolated by the others and each tube bundle can be isolated by the others. 
     
     
         10 . The heat exchanger according to  claim 1 , wherein at least the first tube bundle and/or the second tube bundle is composed of two or more sections, arranged in series. 
     
     
         11 . The heat exchanger according to  claim 1 , wherein the first tube bundle inlet and the first tube bundle outlet and/or the second tube bundle inlet and the second tube bundle outlet, are arranged counterflow relative to said inlet for the first heat ex-change fluid and said outlet for the first heat exchange fluid. 
     
     
         12 . The heat exchanger according to  claim 1 , wherein an additional heat exchanger is arranged upstream the separate sections, the additional heat exchanger being smaller than the heat exchanger. 
     
     
         13 . The heat exchanger according to  claim 1 , wherein a control system is present, wherein the control system comprises differential pressure indicators of the flow of each separate section provided with a respective tube bundle.