Self cleaning filtering apparatus for plate heat exchangers

Abstract

A self cleaning filtering method and apparatus for a plate heat exchanger including: a suction pipe, centrally disposed within an inlet channel adapted for receiving a cooling medium therein for the plate heat exchanger; nozzles extending radially from, and in fluid communication with, the suction pipe, the nozzles spaced apart from each other; a low pressure chamber, external to the heat exchanger, abutting the pressure plate, the low pressure chamber in fluid communication with the inlet channel, and a section of the suction pipe extending into the low pressure chamber; a drain valve adapted to reversibly open a drain of the low pressure chamber; and a rotation mechanism controlling axial rotation of the suction pipe.

What is claimed is: 
     
         1 . A self cleaning filtering apparatus for a plate heat exchanger having a frame plate, a pressure plate and a plate pack disposed between the frame plate and the pressure plate, the apparatus comprising:
 a suction pipe, centrally disposed within an inlet channel adapted for receiving therein a cooling medium for the plate heat exchanger;   nozzles extending radially from, and in fluid communication with, said suction pipe, said nozzles being spaced apart from each other;   a low pressure chamber, external to the heat exchanger, abutting the pressure plate, said low pressure chamber in fluid communication with said inlet channel, and a section of said suction pipe extending into said low pressure chamber;   a drain valve adapted to reversibly open a drain of said low pressure chamber; and   a rotation mechanism controlling axial rotation of said suction pipe.   
     
     
         2 . The apparatus of  claim 1 , wherein evacuation of said cooling medium from said low pressure chamber exerts a negative pressure on said suction pipe, resulting in a backwash process whereby particulates are suctioned via said nozzles, through said suction pipe into said low pressure chamber and out said drain. 
     
     
         3 . The apparatus of  claim 2 , further comprising a screen cylinder fitted in said inlet channel, said screen cylinder adapted to filter said particulates from said cooling medium. 
     
     
         4 . The apparatus of  claim 1 , wherein said nozzles are spaced apart from each other both radially and axially. 
     
     
         5 . The apparatus of  claim 1 , wherein said rotation mechanism is an automated rotation mechanism. 
     
     
         6 . The apparatus of clam  5 , wherein said drain valve is an automatedly actuated valve. 
     
     
         7 . The apparatus of  claim 1 , wherein said low pressure chamber is in fluid communication with a pump operationally coupled to said drain, said pump adapted, when actuated, to exert a suction force on said suction pipe. 
     
     
         8 . The apparatus of  claim 1 , wherein said rotation mechanism is a manually operated rotation mechanism. 
     
     
         9 . The apparatus of  claim 1 , wherein said rotation mechanism includes a linear actuator. 
     
     
         10 . The apparatus of  claim 9 , wherein said linear actuator is a hydraulic motor including a cylinder, a piston and a piston rod, said piston rod being operationally coupled to said suction pipe and adapted, when actuated, to cause linear and rotational movement of said suction pipe and said nozzles. 
     
     
         11 . The apparatus of  claim 1 , wherein said rotation mechanism further controls a linear movement of said suction pipe. 
     
     
         12 . The apparatus of  claim 1 , wherein said suction pipe is an extensible suction pipe. 
     
     
         13 . The apparatus of  claim 3 , wherein said screen cylinder is an extensible screen cylinder. 
     
     
         14 . A method for self cleaning a plate heat exchanger, the method comprising the steps of:
 providing an apparatus for effecting a self cleaning process, said apparatus including:
 a suction pipe, centrally disposed within an inlet channel adapted to receive therein a cooling medium for the plate heat exchanger, 
 nozzles extending radially from said suction pipe, said nozzles being spaced apart from each other, 
 a low pressure chamber, external to the heat exchanger, abutting a pressure plate of the plate heat exchanger, said low pressure chamber in fluid communication with said inlet channel, said suction pipe extending into said low pressure chamber, 
 a drain valve adapted to reversibly open a drain of said low pressure chamber, and 
 a rotation mechanism controlling axial rotation of said suction pipe; 
   opening said drain valve to evacuate said cooling medium from said low pressure chamber and exert a negative pressure on said suction pipe;   actuating said rotation mechanism to axially rotate said suction pipe; and   suctioning particulates from said inlet channel, via said nozzles, through said suction pipe into said low pressure chamber and out said drain.   
     
     
         15 . The method of  claim 14 , wherein said apparatus further comprises a screen cylinder fitted in said inlet channel, said screen cylinder adapted to filter said particulates from said cooling medium; wherein said particulates are suctioned from said screen cylinder. 
     
     
         16 . The method of  claim 14 , wherein said drain valve is manually actuated. 
     
     
         17 . The method of  claim 14 , wherein said rotation mechanism is a manually operated rotation mechanism. 
     
     
         18 . The method of  claim 14 , wherein said drain valve is automatedly actuated. 
     
     
         19 . The method of  claim 18 , wherein said rotation mechanism is an automated rotation mechanism. 
     
     
         20 . The method of  claim 18 , wherein said low pressure chamber is in fluid communication with a pump operationally coupled to said drain, said pump adapted, when actuated, to exert a suction force on said suction pipe. 
     
     
         21 . The method of  claim 18 , wherein said rotation mechanism includes a linear actuator. 
     
     
         22 . The method of  claim 21 , wherein said linear actuator is a hydraulic motor including a cylinder, a piston and a piston rod, said piston rod being operationally coupled to said suction pipe and adapted, when actuated, to cause linear and rotational movement of said suction pipe and said nozzles. 
     
     
         23 . The method of  claim 14 , wherein said rotation mechanism further causes a linear movement of said suction pipe.