US20220268537A1

US20220268537A1 - Self cleaning filtering apparatus for plate heat exchangers

Info

Publication number: US20220268537A1
Application number: US17/631,511
Authority: US
Inventors: Zvi Livni; Omer Livni
Original assignee: Individual
Current assignee: Individual
Priority date: 2019-08-01
Filing date: 2020-07-30
Publication date: 2022-08-25
Also published as: CN114127504A; WO2021019494A1

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.

Description

FIELD OF THE INVENTION

The present invention is directed to a filtering apparatus for industrial and commercial plate heat exchangers.

BACKGROUND OF THE INVENTION

The process heat generated in plants and the like is dissipated with plate and tube heat exchangers. Plate heat exchangers have a multitude of very thin plates between which liquids or gas circulate, to enable heat exchange. Impurities such as rust, debris, biofilm and other various types of suspended solids present in the water penetrate the heat exchanger and block the water conduits reducing the efficiency of a heat exchanger to the extent that its heat exchange efficiency is severely reduced, which makes cleaning of the heat exchanger inevitable. Cleaning plate heat exchangers is a long and cumbersome operation that usually requires the heat exchange process to be stopped, and the heat exchanger to be opened, wasting a considerable amount of time and causing a loss of production, This process is not done on a daily basis and is avoided as much as possible. Therefore, the accumulation of the suspended matter in the heat exchangers causes significant efficiency loss between cleanups.
It is desired to have system that protects heat exchangers from efficiency loss due to clogging.

SUMMARY OF THE INVENTION

According to the present invention there is provided 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 including: 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, the suction pipe, the nozzles being 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.
According to further features in preferred embodiments of the invention described below evacuation of the cooling medium from the low pressure chamber exerts a negative pressure on the suction pipe, resulting in a backwash process whereby particulates are suctioned via the nozzles, through the suction pipe into the low pressure chamber and out the drain.
According to still further features in the described preferred embodiments the apparatus further includes a screen cylinder fitted in the inlet channel, the screen cylinder adapted to filter the particulates from the cooling medium.
According to further features the nozzles are spaced apart from each other both radially and axially. According to further features the rotation mechanism is an automated rotation mechanism. According to further features the drain valve is an automatedly actuated valve.
According to further features the low pressure chamber is in fluid communication with a pump operationally coupled to the drain, the pump adapted, when actuated, to exert a suction force on the suction pipe.
According to further features the rotation mechanism is a manually operated rotation mechanism. According to further features the rotation mechanism includes a linear actuator. According to further features the linear actuator is a hydraulic motor including a cylinder, a piston and a piston rod, the piston rod being operationally coupled to the suction pipe and adapted, when actuated, to cause linear and rotational movement of the suction pipe and the nozzles.
According to further features the rotation mechanism further controls a linear movement of the suction pipe. According to further features, the suction pipe is an extensible suction pipe. According to further features, the screen cylinder is an extensible screen cylinder.
According to another embodiment there is provided a method for self cleaning a plate heat exchanger, the method including the steps of: providing an apparatus for effecting a self cleaning process, the 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 the suction pipe, the 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, the low pressure chamber in fluid communication with the inlet channel, 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; opening the drain valve to evacuate the cooling medium from the low pressure chamber and exert a negative pressure on the suction pipe; actuating the rotation mechanism to axially rotate the suction pipe; and suctioning particulates from the inlet channel, via the nozzles, through the suction pipe into the low pressure chamber and out the drain.
According to further features the apparatus further comprises a screen cylinder fitted in the inlet channel, the screen cylinder adapted to filter the particulates from the cooling medium; wherein the particulates are suctioned from the screen cylinder.
According to further features the drain valve is manually actuated. According to further features the rotation mechanism is a manually operated rotation mechanism. According to further features the drain valve is automatedly actuated.
According to further features the rotation mechanism is an automated rotation mechanism.
According to further features the low pressure chamber is in fluid communication with a pump operationally coupled to the drain, the pump adapted, when actuated, to exert a suction force on the suction pipe.
According to further features the rotation mechanism includes a linear actuator. According to further features the linear actuator is a hydraulic motor including a cylinder, a piston and a piston rod, the piston rod being operationally coupled to the suction pipe and adapted, when actuated, to cause linear and rotational movement of the suction pipe and the nozzles.

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments are herein described, by way of example only, with reference to the accompanying drawings, wherein:

FIG. 1 is a sectional view of a plate heat exchanger with the instant innovative self-cleaning filtering apparatus;

FIG. 2 is a sectional view of the plate heat exchanger with apparatus 100 with the addition of a screen cylinder installed therein;

FIG. 3 is a sectional view of the plate heat exchanger with apparatus 100 installed therein with the addition of a pump;

FIG. 4 is a sectional view of the plate heat exchanger with apparatus 100 installed therein with the addition of a pump but without a screen cylinder;

FIG. 5 is a sectional view of the plate heat exchanger with an apparatus 100 with a manual rotation mechanism;

FIG. 6 is a sectional view of the plate heat exchanger with an apparatus 100 with a rotation mechanism that is a linear actuator.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Plate heat exchangers have various configurations and different people use slightly different terminology for the various parts of the plate heat exchanger. In order to minimize confusion and present a clear nomenclature for the various components of the plate heat exchanger, the following description is provided.
The instant innovative apparatus is disclosed with reference to a specific configuration of plate heat exchangers. However, it is made clear that the use of the instant configuration of heat plate exchanger is merely exemplary, and in no way limiting of the scope of the invention. The instantly described apparatus can be implemented in any plate heat exchanger, with minor modifications where necessary.
At least for the purposes of the instant disclosure, the following terminology and configuration of the plate heat exchanger is used: A plate heat exchanger is made up of a frame plate, a pressure plate and a plate pack which is disposed between the frame plate and the pressure plate. For all intents and purposes, the frame plate is the front facing plate which has all the connectors (inlet and outlet of the cooling medium and inlet and outlet of the heated medium). The pressure plate is the back piece. In between the frame and pressure plates is the plate pack. The plate pack consists of a plurality of plates, tightly sandwiched together. A heated medium flows through every alternate plate and a cooling medium flows through every other plate, so that each plate with heated medium has a plate with cooling medium next to it. The cooling medium is generally water. Water runs into the heat exchanger through an inlet channel at the bottom of the plates, on one side. The water heats up as it cools the heated medium and exits through an outlet channel at the top of the plates. There is a similar arrangement on the other side of the plates, this one for the heated medium. However, the intel channel for the heated medium is at the top of the plates and the outlet is channel is at the bottom of the plates.
As mentioned, in the instant disclosure, all the connectors to the channels are disposed on the frame plate. There are other configurations, as mentioned, however, for the sake of conciseness, only the instant configuration is discussed in detail. The inlet and outlet channels are actually the product of each of plates having inlet/outlet openings (left bottom, right bottom, left top and right top of the plate) and the plates being pressed together. The openings from the channel into the plate are generally small. Therefore, the structure of the inlet channel for the cooling medium serves as a filter for the larger particulates that are found in the cooling medium (water). These larger particulates (stones, trash, shells, peel, etc.) block the inlet channel lowering the efficiency of the heat exchanger by blocking the passageways of the cooling medium.
The instant apparatus is a self-cleaning mechanism that removes the aforementioned particulates from the inlet channel. In one embodiment of the innovative apparatus, there is provided a cylinder screen which is fitted inside the inlet channel. The screen cylinder has a slightly smaller diameter than the inlet channel, The screen serves as a filter for both the large particulates mentioned above as well as smaller particulates that would otherwise pass into the body of the plate heat exchanger (i.e. between the plates) and potentially block some of the water pathways, or line the inside of the plates with muck and grime, both of which further reduce the efficiency of the heat exchanger. The innovative self-cleaning apparatus, according to the screen cylinder embodiment, removes the particulates from the screen.
Plate heat exchangers are made up of plates sandwiched together between the frame plate and the pressure plate. The number of plates differs based on the needs of the project at hand. Accordingly, to provide additional versatility, lower the cost of manufacture and afford on-site flexibility, the screen cylinder in some embodiments is accordion-like, able to extend or retract in length based on the side (i.e. number of plates) of the heat exchanger. In a similar fashion to the screen cylinder, and to provide at least the same advantages mentioned heretofore, the suction pipe, according to some embodiments, has a telescopic structure, able to extend or retract in order to fit the length of the inlet channel.
The process for removing the particulates that clog the heat exchanger, in all the embodiments, is called a backwash process. In the backwash process, the particulates are suctioned out of the inlet channel. Innovatively, the backwash process occurs inside the inlet channel of the plate heat exchanger. Further innovatively, the backwash process can commence and run even while the heat exchanger is working normally, i.e. fresh water is entering inlet channel of the heat exchanger.
The principles and operation of the self-cleaning filtering apparatus for plate heat exchangers according to the present invention may be better understood with reference to the drawings and the accompanying description.
FIG. 1 illustrates a sectional view of a plate heat exchanger 10 with the instant innovative self-cleaning filtering apparatus 100, according to one embodiment, installed, at least partially, in a water inlet channel 12 of the plate heat exchanger 10. The figure illustrates the half of the plate heat exchanger which includes the cooling medium (e.g. water) inlet 12 (lower end) and outlet 14 (upper end) channels. As mentioned, the plate heat exchanger 10 has a frame plate 16, a pressure plate 18 and a plate pack 20 which is disposed between the frame plate and the pressure plate.
The self cleaning filtering apparatus 100 includes a suction pipe 102 which is centrally disposed within the inlet channel 12 that is adapted for receiving a cooling medium (e.g. water) for the plate heat exchanger. The suction pipe extends through an aperture in the pressure plate such that a section 104 of the suction pipe 102 extends out of the native plate heat exchanger and into the low pressure chamber. On the frame plate side (right side in the diagram), the suction pipe is propped up and held in place by a circular disk 106 with an aperture in the center thereof.
There is a plurality of nozzles 108 extending radially from, and in fluid communication with, the suction pipe 102. Each nozzle is spaced apart from the adjacent nozzle. The nozzles are spaced apart axially (i.e. along the axis of the pipe).
Preferably, at least some of the nozzles are also spaced apart radially (i.e. facing a different direction). Each nozzle is a hollow pipe section that is connected (e.g. welded) to the suction pipe. The nozzle is open is the distal end of thereof. Particulates are suctioned through the top opening 109 of the nozzle and into the suction pipe and eventually out the apparatus.
A low pressure chamber 110 is installed external to the heat exchanger, abutting the pressure plate 18. The low pressure chamber 110 is installed in-line with the inlet channel and has the same diameter. The low pressure chamber is in limited fluid communication with the inlet channel, e.g. through the suction pipe which opens into the chamber. Under normal pressure (i.e. pressure in the chamber is equal to the pressure in the inlet channel) the chamber fills with water from the inlet channel (e.g. through the nozzles and suction pipe). As mentioned, a section 104 of the suction pipe extends into the low pressure chamber. The suction pipe does not extend all the way to the opposite wall of the chamber, rather a connector rod 112, mechanically couples the suction pipe to a rotation mechanism.
The low pressure chamber 110 has a drain 114 for evacuating the water from the chamber. A drain valve 116 closes the drain and is adapted to reversibly open the drain when actuated. In the instantly depicted embodiment, the drain valve is an automatedly actuated valve. For example, the drain valve may be a solenoid valve, such as a normally closed solenoid valve. Preferably, the drain valve is adapted to be electrically actuated. More preferably, the drain valve is adapted to be remotely actuated.
Actuation of the drain valve opens the drain and causes evacuation of the cooling medium from the low pressure chamber. The pressure in the chamber is lowered relative to the pressure in the inlet channel such that a vacuum (negative) pressure is exerted on the suction pipe, resulting in a backwash process taking place. In the backwash process (also described above) particulates are suctioned from the periphery of the inlet channel into the nozzles, as the nozzles rotate about the axis of the suction pipe. The particulates continue to travel through the suction pipe, exiting out of the opening of the section of the suction pipe where the rod enters the pipe. There is sufficient space around the rod for the particulates to exit into the chamber. The water and particulates wash out of the drain of the chamber.
The rotation mechanism controls the axial rotation of the suction pipe 102. In the instantly depicted embodiment, the rotation mechanism is a motorized mechanism such as an electric motor 118. The motor rotates the rod which rotates the suction pipe such that the nozzles rotate about the periphery of the inlet channel, suctioning up the debris and particulates that are trapped there.
In preferred embodiments, the rotation mechanism also causes a linear movement of the suction pipe. According to the embodiment which further includes linear motion, the nozzles move in a spiral pattern, as opposed to a circular or rotational pattern (in embodiments without linear movement). A spiral pattern ensures that more of the surface area of the periphery of the inlet channel is cleaned during the backwash process.
The drain valve and rotation mechanism are both controlled by a control unit (not shown). The control unit is in electrical communication with the drain valve and the rotation mechanism. The control unit may be in wired or wireless communication. The control unit may be local or remote.
Another possible configuration is shown in FIG. 2. FIG. 2 illustrates a sectional view of apparatus 100 with the addition of a screen cylinder 120. The screen cylinder 120 is fitted in the inlet channel and adapted to filter particulates from the cooling medium (e.g. water). Screen cylinder 120 is a filter screen with a filter mesh that is adapted to trap or filter particulates that would otherwise block the openings into the plates or pass into the body of the plate heat exchanger and either be flushed out, or more likely, gather inside the heat exchanger, between the plates. These particulates, as mentioned above, clog the plates and lower the overall efficiency of the plate heat exchanger.
According to the instant embodiment, if necessary, the nozzles 108, disk 106 and any other corresponding components are adapted, mutatis mutandis, to accommodate the screen cylinder 120. The nozzles suction the particulates off the screen cylinder (as opposed to the periphery of the inlet channel, as shown in FIG. 1) during the backwash process.
The drain valve and rotation mechanism are both controlled by a control unit (not shown). The control unit is in electrical communication with the drain valve and the rotation mechanism. The control unit may be in wired or wireless communication. The control unit may be local or remote.
Yet another configuration is shown in FIG. 3. FIG. 3 illustrates a sectional view of the plate heat exchanger with apparatus 100 installed therein with the addition of a pump 122 operationally coupled to the drain 114. Pump 122 may be a mechanical or electromechanical pump. The low pressure chamber 110 is in fluid communication with pump 122. Pump 122 is adapted, when actuated, to exert negative pressure (suction force) on the suction pipe 102. The pump lowers the pressure in the chamber 110 to a greater degree than merely evacuating the contents of the chamber by opening the drain valve (in the aforementioned embodiments). The pump increases the suction force at the nozzles relative to the embodiments without a pump. The drain valve (not shown) is preferably integrated into the pump mechanism (before the drain pipe).
The pump, drain valve and rotation mechanism are all controlled by a control unit (not shown). The control unit is in electrical communication with the pump, the drain valve and the rotation mechanism. The control unit may be in wired or wireless communication. The control unit may be local or remote.
FIG. 4 illustrates the same configuration as FIG. 3 except that the instant embodiment is devoid of a cylinder screen. Other than that, all the components and processes are the same as the embodiment depicted in FIG. 3.
It is noted that many of the same components are found in each of the described embodiments. For the sake of conciseness and continuity, the same components are not described in detail for each embodiment but are rather described at least once throughout the disclosure and that description is to be seen as is fully set forth for each embodiment. The same applies to the accompanying processes.
Another configuration is shown in FIG. 5. FIG. 5 illustrates a sectional view of the plate heat exchanger with an apparatus 100 with a manual rotation mechanism. The exemplary manual rotation mechanism depicted in the Figure is a hand crank or handle 124. The handle is adapted to be rotated by hand, rotating the suction pipe and nozzles about the axis of the rod 112 coupled to the suction pipe 102. In some embodiments, the handle 124 is further adapted to effect linear movement of the suction pipe, thereby increasing the surface area covered by the rotating nozzles.
In the Figure, the drain valve is depicted as having a solenoid valve. It is to be understood that the depiction of the automatedly actuated drain valve is merely exemplary and not intended to be limiting. As such, in alternative embodiments, the drain valve may be a manually operated drain valve. Alternatively or additionally, the rotation mechanism can be operationally coupled to the drain valve such that manual actuation of the rotation mechanism also effects the operation of the drain valve, for either a manually or automatically actuated valve.
It is further noted that the depiction/inclusion of a screen cylinder is merely exemplary and not intended to be limiting. That is to say that implementation of the manual rotation mechanism in an apparatus without a cylinder screen 120 is also within the scope of the invention.
Yet another configuration is depicted in FIG. 6. FIG. 6 illustrates a sectional view of the plate heat exchanger with an apparatus 100 with a rotation mechanism that is a linear actuator. In the Figure, the linear actuator is a linear hydraulic motor 126. It is noted that other types of linear actuators know in the art can be used in place of the linear hydraulic motor. Examples of types of linear actuators include, but are not limited to, mechanical actuators (e.g. screw, wheel, cam type actuators), hydraulic actuators, pneumatic actuators, piezoelectric actuators, twisted and coiled polymer (TCP) actuators and electromechanical actuators.
Hydraulic motor 126 includes a cylinder 132, a piston 134 and a piston rod 136. The piston rod 136 is operationally coupled to the suction pipe and adapted, when actuated, to cause linear and rotational movement of the suction pipe and the nozzles.
The section 104 of the suction pipe 102, according to the instant embodiment, includes two fins 128 that extend radially from opposite locations on the section 104 of the suction pipe 102. Each of the fins is in fluid communication with the suction pipe and the low pressure chamber 110. Each fin has an opening 130 near the distal edge of the fin. Water and particulates suctioned out of the inlet channel 102 during the backwash process exit the suction pipe through the openings 130. The water and detritus wash down the drain 114 either under the force of gravity or, in embodiments with a pump, under the suction force of the pump. As intimated, the present configuration including a hydraulic motor can be applied to any of the aforementioned configurations, mutatis mutandis Likewise, the arrangement of the section 104 of suction pipe 102 as depicted in FIG. 6 can be similarly applied to other embodiments disclosed herein.
Sectional views of only a cylinder 132, the piston 134 and the piston rod 136 are shown in the Figure. The remaining components of the hydraulic motor are not show, but are well known in the art.
Referring now to all of the aforementioned configurations, a modification that can be applied to each of the embodiments is a variation whereby the suction pipe 102 is a telescopic pipe, adapted to extend to a predefined length and retract to a second predefined length. As mentioned, the telescopic structure affords additional versatility and lowers cost of manufacture by avoiding the need to fabricate a suction pipe of the precise length of the inlet channel for each separate project. Furthermore, the telescopic nature of the pipe provides flexibility in the field as last-minute changes to the size of the plate heat exchanger (i.e. the number of plates in the plate pack) may take place and the dynamic length of the suction pipe will prevent further delays of ordering or manufacturing a new pipe.
Alternatively, but affording all of the same advantages, the suction pipe, according to another variation, is a modular suction pipe whereby the length of the pipe can be lengthened or shortened by adding or removing sectional pieces that fit onto or into the suction pipe (without the need for cutting or welding etc.) according to the precise needs of the project at hand.
A similar modification can be applied to all of the foregoing embodiments that include a screen cylinder. The screen cylinder, according to the present variation, has, at least partially, an accordion-like structure, enabling the screen cylinder to extend from a first predefined length up to a second predefined length. Additional length extending structures and techniques, for both the suction pipe and the cylinder screen, are considered to fall within the scope of the invention. Therefore, according to some embodiments the suction pipe 102 is an extensible suction pipe. According to some embodiments, the screen cylinder 120 is an extensible screen cylinder.
A similar process is applied to all the embodiments disclosed heretofore. The method for self-cleaning a plate hear exchanger, includes steps detailed hereafter. Initially, the self cleaning apparatus 100 must be provided. The apparatus can be installed during the manufacturing process of the plate heat exchanger or during assembly of a plate heat exchanger on site. Alternatively, a plate heat exchanger that is in use already (i.e. previously functioning without the self-clean apparatus installed therein) can be retrofit, on-site, even after operation of the heat exchanger has begun. Accordingly, the plate heat exchanger can be retrofit with the self-cleaning apparatus of the instant invention.
As part of the installation process, the suction pipe must be installed such that it is centrally disposed within the inlet channel that receives the cooling medium (e.g. water) for the plate heat exchanger. The nozzles extend radially from the suction pipe. As discussed above, the nozzles are spaced apart from each other. They can be spaced apart longitudinally along the axis of the suction pipe. In addition, the nozzles can also be spaced apart radially, i.e. about the axis of the tube. If necessary, the suction pipe can be extensibly adjusted to fit the length of the inlet channel.
The low pressure chamber is installed on (or abutting) the pressure plate, on the outside of the native heat exchanger. The suction pipe extends into the low pressure chamber. The low pressure chamber is in fluid communication with the inlet channel, e.g. via the suction pipe. The chamber has a drain that is opened and closed by a drain valve. The apparatus also includes the rotation mechanism that controls axial rotation of the suction pipe. Once all of these components have been installed, the plate heat exchanger is ready to operate (or restart operation after being retrofit with the apparatus).
The backwash process cleans the inlet channel of particulates that are trapped on the peripheral surface of the inlet channel, at the openings through which the water travels between the plates. The process includes opening the drain valve to evacuate the cooling medium from the low pressure chamber. Evacuation of the water in the chamber lowers the pressure in the chamber and causes a vacuum pressure to be exerted on the suction pipe.
The process further involves actuating the rotation mechanism to axially rotate the suction pipe and hence the nozzles. The nozzles begin suctioning particulates from the inlet channel. Water and particulates sucked in via the nozzles travel through the suction pipe and are deposited into the low pressure chamber. From there, the water and particulates wash out of the drain.
In some embodiments, the apparatus further includes a screen cylinder fitted in the inlet channel. The screen cylinder is adapted to filter particulates from cooling medium. In such embodiments, the particulates are suctioned from the screen cylinder. Here too, if necessary, the accordion-like screen cylinder can be extended to the correct length to fit the inlet channel.
In some embodiments the drain valve is a manual mechanism that is manually actuated. In others, the drain valve is an automated mechanism that is automatically actuated. In some embodiments the rotation mechanism is a manually operated rotation mechanism that is manually actuated. In other embodiments, the rotation mechanism is an automated rotation mechanism that is automatically actuated.
In some embodiments, a pump is operationally coupled to the drain and exerts an increased vacuum pressure/suction force on the chamber and the suction pipe. In some embodiments, the rotation mechanism includes a linear actuator. The linear actuator may be any type of applicable linear actuator. In one embodiment, the linear actuator is a hydraulic motor including a cylinder, a piston and a piston rod. The piston rod is operationally coupled to the suction pipe and adapted, when actuated, to cause linear and rotational movement of the suction pipe and, hence, the nozzles. In other embodiments, any one of the rotational mechanisms discussed above further causes a linear movement of the suction pipe.
While the invention has been described with respect to a limited number of embodiments, it will be appreciated that many variations, modifications and other applications of the invention may be made. Therefore, the claimed invention as recited in the claims that follow is not limited to the embodiments described herein.

Claims

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.