Heat exchanger component configured for mitigation of scaling and method of mitigating scaling during a heat transfer process

Abstract

A heat exchanger component configured for mitigation of scaling has a surface including a wettability pattern thereon. The wettability pattern comprises hydrophobic regions and hydrophilic regions. A method of mitigating scaling during a heat transfer process includes providing a heat exchanger component having a surface including a wettability pattern thereon, where the wettability pattern comprises hydrophobic regions and hydrophilic regions. The heat exchanger component is introduced into a heat transfer process, where the surface of the heat exchanger component is exposed to flow of a process fluid. During the exposure to flow of the process fluid, scale deposits form with a nonuniform thickness distribution and/or a nonuniform adhesion force over the wettability pattern on the surface. The flow of the process fluid introduces a shear force that periodically or intermittently removes the scale deposits, thereby enabling self-cleaning of the surface.

What is claimed is: 
     
         1 . A heat exchanger component configured for mitigation of scaling, the heat exchanger component comprising:
 a surface including a wettability pattern thereon, the wettability pattern comprising hydrophobic regions and hydrophilic regions.   
     
     
         2 . The heat exchanger component of  claim 1 , wherein the hydrophobic regions comprise coated regions of the surface, the coated regions including a hydrophobic coating, and
 wherein the hydrophilic regions comprise uncoated regions of the surface.   
     
     
         3 . The heat exchanger component of  claim 1 , wherein the hydrophobic coating comprises a polymer, silica, metal oxide, carbon nanotubes, and/or wax. 
     
     
         4 . The heat exchanger component of  claim 1 , wherein the surface comprises a curved surface. 
     
     
         5 . The heat exchanger component of  claim 1 , wherein the heat exchanger component comprises a tube. 
     
     
         6 . The heat exchanger component of  claim 1 , wherein the wettability pattern comprises an alternating pattern of the hydrophobic regions and the hydrophilic regions. 
     
     
         7 . The heat exchanger component of  claim 1 , wherein areal coverage of the hydrophobic regions over the surface is in a range from 10-50%. 
     
     
         8 . The heat exchanger component of  claim 1 , wherein the wettability pattern includes an alternating pattern of the hydrophobic and the hydrophilic regions, and wherein, within the alternating pattern, the hydrophilic regions are wider than the hydrophobic regions. 
     
     
         9 . The heat exchanger component of  claim 1 , wherein a ratio of the width of the hydrophilic regions to the width of the hydrophobic regions is in a range from about 2:1 to about 5:1. 
     
     
         10 . The heat exchanger component of  claim 1 , wherein a width of each of the hydrophobic and the hydrophilic regions is in a range from about 0.5 mm to about 25 mm. 
     
     
         11 . The heat exchanger component of  claim 1 , wherein the wettability pattern comprises a strip coating pattern, a ring coating pattern, a grid coating pattern, and/or a hybrid coating pattern. 
     
     
         12 . The heat exchanger component of  claim 1  being a tube, and
 wherein the hydrophobic regions have a form of first strips extending in a longitudinal direction and wherein the hydrophilic regions have a form of second strips extending in the longitudinal direction and alternating with the first strips. 
 
     
     
         13 . The heat exchanger component of  claim 1  being a tube, and
 wherein the hydrophobic regions have a form of first rings extending in a circumferential direction and wherein the hydrophilic regions have a form of second rings extending in the circumferential direction and alternating with the first rings. 
 
     
     
         14 . The heat exchanger component of  claim 13 , wherein the hydrophilic regions further comprise a longitudinal band extending from a first end to a second end of the tube and intersecting with the first and second rings. 
     
     
         15 . The heat exchanger component of  claim 14 , wherein the longitudinal band has a circumferential angle ⊖ in a range from −45 degrees to +45 degrees. 
     
     
         16 . A method of mitigating scaling during a heat transfer process, the method comprising:
 providing a heat exchanger component having a surface including a wettability pattern thereon, the wettability pattern comprising hydrophobic regions and hydrophilic regions;   introducing the heat exchanger component into a heat transfer process, the surface of the heat exchanger component being exposed to flow of a process fluid;   wherein, during the exposure to flow of the process fluid, scale deposits form with a nonuniform thickness distribution and/or a nonuniform adhesion force over the wettability pattern on the surface, and   wherein the flow of the process fluid introduces a shear force that periodically or intermittently removes the scale deposits, thereby enabling self-cleaning of the surface.   
     
     
         17 . The method of  claim 16 , wherein the heat transfer process is part of thermal desalination or food processing. 
     
     
         18 . The method of  claim 16 , wherein the process fluid has a Reynolds number of at least 350. 
     
     
         19 . The method of  claim 16 , wherein the heat transfer process includes evaporation of the process fluid in a horizontal tube falling film evaporator. 
     
     
         20 . A method of applying a wettability pattern to a heat exchanger component, comprising:
 cleaning a surface of a heat exchanger component;   covering a portion of the surface of the heat exchanger component with surface protection, wherein the surface protection is removable from the surface of the heat exchanger component without altering the surface;   after covering the portion of the surface with surface protection, applying a hydrophobic coating to the surface; and   after applying the hydrophobic coating, removing the surface protection from the portion of the surface, thereby exposing a hydrophilic region and producing a wettability pattern on the surface.