APPARATUS AND METHOD FOR CLEANING A PLATE HEAT EXCHANGER

Description

FIELD OF THE DISCLOSURE

The present application relates to an apparatus and method for the cleaning of a plate heat exchanger. More specifically, the application relates to an apparatus and method for targeted cleaning of plate heat exchangers in industrial settings.

BACKGROUND

Heat exchangers are used across many industries to transfer thermal energy between two mediums, such as two liquids. The heat exchange occurs without the mixing of the two media.

A plate heat exchanger is a specific type of heat exchanger that is used in industries such as building services and manufacturing. In the plate heat exchanger, many plates are kept in close proximity to provide a large surface area for heat transfer as the fluids pass along plates in the plate heat exchanger. Gaskets sit between the plates to seal the plates from one another. Cool fluid and warm fluid enter the plate heat exchanger through different inlets. Once the cool fluid and warm fluid is in the plate heat exchanger, they both travel across different sides of the plates without those two fluids intermixing. As the fluids pass across the plates, thermal energy is transferred through the plate from the warmer fluid to the cooler fluid.

After some time in operation with a significant amount of fluid or other media passing along the plates of the plate heat exchanger, there can be an unwanted accumulation of material, such as calcium and magnesium salts, onto the heat transfer plates. This buildup is often referred to as “fouling”. If the plate heat exchanger is not cleaned regularly, the fouling can lead to significant problems in the operation of the plate heat exchanger. For instance, fouling can increase the heat resistance of the surface of the plates, reducing efficient heat transfer, and can block the flow paths of the fluid passing through the heat exchanger, reducing the rate of fluid flow and efficient heat transfer as a result.

There are two traditional methods for cleaning plate heat exchangers. The first method involves manually spraying or scraping each of the fouled plates of the plate heat exchanger individually. While this is an effective way to ensure the fouled plates are cleaned, the task of loosening the tightening bolts of the plate heat changer, locating the fouled plates, and spraying or scraping each fouled plate individually can be very time consuming. The prolonged cleaning further leads to inconveniences since the plate heat exchanger cannot be used for the duration of the cleaning.

Another common method of cleaning plate heat exchangers is by flushing the plate heat exchanger with a cleaning fluid. Typically, the cleaning fluid enters the plate heat exchanger through the same inlets in which the fluid to be heated or cooled ordinarily enters the plate heat exchanger during operation. This method does not require disassembly and is thus easier and less time consuming to perform. However, this method of cleaning the plate heat exchanger also suffers from deficiencies. While the cleaning time may be shortened, there are issues with ensuring that the plates are adequately cleaned. Generally, when cleaning fluid is pumped through the entire plate heat exchanger, the fluid follows the path of least resistance. Thus, the cleaning fluid preferably travels across the unfouled plates, avoiding the fouled plates that are in need of cleaning. This leads to wasted cleaning fluid and may prolong the cleaning process.

As described above, current methods for cleaning of plate heat exchangers are inefficient and lead to prolonged cleaning, increased costs to operators, and potential environmental impacts of using excess cleaning fluid.

SUMMARY

In one aspect, there is provided an apparatus for cleaning a plate heat exchanger, the apparatus comprising, a fluid transfer section having a first end, a connecting section disposed on the fluid transfer section, and a distribution section adjacent to the first end of the fluid transfer section, wherein the fluid transfer section is movable with respect to the connecting section.

In some embodiments, the connecting section comprises an adaptor and a sealing member. In some embodiments, the connecting section further comprises a connector which removably connects the adaptor and the sealing member.

In some embodiments, the distribution section comprises and open end, a closed end and a middle section. In some embodiments, the middle section is movable with respect to the open end and/or the closed end of the distribution section. In some embodiments, the middle section comprises at least two rods.

In some embodiments, the fluid transfer section has a second part and further comprising a handle disposed on the second part of the fluid transfer section.

In another aspect, a method is provided for cleaning a plate heat exchanger having at least one input port, the method comprising, providing a cleaning apparatus, the cleaning apparatus having a fluid transfer section and a distribution section, inserting the cleaning apparatus into an input port of the plate heat exchanger, securing the cleaning apparatus to the plate heat exchanger using an adaptor disposed on the fluid transfer section, and pumping cleaning fluid into a second end of the fluid transfer section, wherein the cleaning fluid exits the cleaning apparatus and enters the plate heat exchanger at the distribution section and wherein the distribution section is set at a specific length such that cleaning fluid is delivered to a selection of at least one target plate within the plate heat exchanger.

In some embodiments, the method further comprising moving the fluid transfer section relative to the adaptor and pumping cleaning fluid in a second selection of at least one target plate.

Other aspects and features of the present disclosure will become apparent, to those ordinarily skilled in the art, upon review of the following description of the specific embodiments of the disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure will be better understood having regard to the drawings in which:

FIG. 1 is an exploded perspective view of a typical plate heat exchanger;

FIG. 2 is a perspective view of one embodiment of the cleaning apparatus described herein;

FIG. 3 is a side view of the cleaning apparatus shown in FIG. 2; and

FIG. 4 is a side view of the distribution section of the cleaning apparatus shown in FIG. 2.

DETAILED DESCRIPTION

FIG. 1 shows, in very general terms, the basic components of a typical plate heat exchanger 10. Specifically, it has a cold input channel or port 12, where the cold/cool fluid enters the exchanger 10, and hot input channel or port 14, where the hot/warm fluid enters the exchanger 10 and numerous plates 16 over which the cold/cool or hot/warm fluid passes and through which heat is transferred from the hot/warm fluid to the cold/cool fluid. The hot/warm and cold/cool temperatures are relative to each other.

The present disclosure generally provides a cleaning apparatus 100 for cleaning fouling from the plates 16 of a plate heat exchanger 10. As shown in FIGS. 2 and 3, the cleaning apparatus 100 comprises a fluid transfer section 102, a connecting section 110 and a distribution section 104. When in use, the distribution section 104 and a first part 106 of the fluid transfer section 102 are positioned within the cold input port 12 or the hot input port 14 prior to pumping the cleaning fluid through the plate heat exchanger 10. In this disclosure, the term “cleaning fluid” refers to the liquid that is used to clean fouling from the plates 16 of a plate heat exchanger 10 and is also commonly referred to a “defouling” fluid.

The fluid transfer section 102 of the cleaning apparatus 100 comprises a first part 106 and a second part 108. In some embodiments, the first part 106 and the second part 108 can be comprised of a stiff pipe, hose or tubing that is movable with respect to the connecting section 110. In other embodiments, the fluid transfer section 102 can be comprised of a plurality of adjacent sections of pipe, hose and/or tubing that together are moveable with respect to the connecting section 110. The first part 106 refers to the section of the fluid transfer section 102 that is positioned within the plate heat exchanger 10 when in use, whereas the second part 108 refers to the section of the fluid transfer section 102 that is positioned outside the plate heat exchanger 10 when in use. In a some embodiments, the fluid transfer section 102 is a pipe. The fluid transfer section 102 can be made of any material that is able to meet the required specifications for transporting cleaning fluid to the plate heat exchanger 10. For example, the fluid transfer section 102 can be made of a material that can withstand the design pressure of the exchanger. The fluid transfer section 102 can be made of any stiff material that has a pressure rating no less than the design pressure of the exchanger. In some embodiments the fluid transfer section 102 can be made of metal, or plastic.

The connecting section 110 comprises an adaptor 122 and a sealing member 124 and is disposed on the fluid transfer section 102, such that the fluid transfer section 102 is moveable with respect to the connecting section 110. Put another way, the connecting section 110 is movable along the fluid transfer section 102, although the connection section 110 is typically stationary when in use. The adaptor 122 functions to connect the cleaning apparatus 100 to the plate heat exchanger 10. The adaptor 122 is changeable, such that the size of the adaptor can be changed as needed to accommodate various sizes for ports, 12, 14 found in different plate heat exchangers 10. In some embodiments the port size has an internal diameter of 2″, 3″, 4″, 6″, 8″, 12″, 14″, 16″ or 18″. In some embodiments the adaptor 122 can be a flange that is removably attached to a plate heat exchanger 10 using a fastener, for example nuts and bolts or screws. The sealing member 124 functions to prevent cleaning fluid from leaking out of the plate heat exchanger 10 during cleaning, in particular it prevents cleaning fluid from leaking along the outside of the fluid transfer section 102. In some embodiments, the sealing member 124 is a stuffing box. In other embodiments, the sealing member 124 is a mechanical seal, a lip seal, a labyrinth seal, a magnetic seal or a diaphragm seal.

In some embodiments, the connecting section 110 further comprises a connector 126, which removably connects the adaptor 122 and the sealing member 124. In some embodiments, the adaptor 122, the sealing member 124 and/or the connector 126 (when present) completely surround part of the fluid transfer section 102.

In some embodiments a handle 120 is disposed on the second part 108 of the fluid transfer section 102. The handle 120 functions to provide a means for a user to move the fluid transfer section 102 relative to the connecting section 110, so that the ratio of the first part 106 to the second part 108 changes. In some embodiments, the handle 120 can be at least one member that extends from the second part 108 or at least one grip section on the outer surface of the second part 108. In some embodiments, the handle 120 comprises two members that extend substantially perpendicular from the second part 108 of the fluid transfer section 102. However, it is understood that the handle 120 can refer to anything that facilitates the users'ability to move the fluid transfer section 102 relative to the connecting section 110.

The fluid transfer section 102 also has a first end 114 and a second end 116. When in use, the second end 116 is fluidly connected to an apparatus which pumps cleaning fluid into the cleaning apparatus 100. The cleaning fluid travels into the second end 116 and out of the first end 114. The distribution section 104 is adjacent the first end 114 of the fluid transfer section 102.

As shown in FIG. 4, the distribution section 104 comprises an open end 128, a closed end 130 and a middle section 132. Cleaning fluid injected into the cleaning apparatus 100 travels through the fluid transfer section 102 to the open end 128 of the distribution section 104 and then enters the plate heat exchanger 10 via the middle section 132 of the distribution section 104. In some embodiments the open end 128 of the distribution section 104 comprises one opening, either the same or a different size than the opening in the fluid transfer section 102. In other embodiments, the open end 128 of the distribution section 104 comprises a plurality of openings, which can be the same or different sizes and/or shapes. In some embodiments the open end 128 of the distribution section 104 is configured to direct how cleaning fluid enters the plate heat exchanger 10 via the middle section 132 of the distribution section 104. The single or plurality of openings The closed end 130 of the distribution section 104 is a solid piece of material which functions to limit the distance within the plate heat exchanger the cleaning fluid can reach, and thereby limit the number of plates 16 in the plate heat exchanger 10 that are being actively treated by the cleaning fluid at any particular time. In some embodiments the distribution section 104 can be removable so that distribution sections 104 of differing diameters and/or different lengths can be used with the same fluid transfer section 102. This allows the cleaning apparatus 100 to properly fit into the different sized ports 12, 14 of various plate heat exchangers 10 and to change the number of plates 16 being cleaned at one time.

The middle section 132 connects the open end 128 and the closed end 130 of the distribution section 104 and functions to allow cleaning fluid to enter the plate heat exchanger 10. In some embodiments, the middle section 132 can be a pipe having at least one opening through which the cleaning fluid may enter to plate heat exchanger 10. In other embodiments, the middle section 132 can be at least two rods having space therebetween to allow cleaning fluid to enter the plate heat exchanger 10. In some embodiments, the middle section 132 can vary in length to allow the cleaning apparatus 100 to target different numbers of plates 16 for specific cleaning. In some embodiments the varying length of the middle section 132 can be the result of the middle section 132 being movable with respect to the open end 128 and/or the closed end 130. In other embodiments, the middle section 132 can be a fixed length and is switched out when the number of plates 16 to be cleaned changes.

In some embodiments, the distribution section 104 can also include a first gasket 134 disposed on the open end 128 of the distribution section 104 and/or a second gasket 136 disposed on the closed end 130 of the distribution section 104. When in use, the first and/or second gaskets 134, 136, function to prevent cleaning fluid from entering the plate heat exchanger 10 outside of the targeted plates 16. The gaskets 134, 136 can be removable so that appropriate diameter gaskets 134, 136 can be used with the various diameter ports 12, 14 that can be found in plate heat exchangers 10. In some embodiments, the first and/or second gaskets 134, 136 can be positioned between two flanges. In other embodiments, the first and/or second gaskets 134, 136 are o-rings positioned around the circumference of a flange. In some embodiments, the gaskets provide sufficient sealing to prevent the escape of cleaning fluid from the at least one target plate, but also allow for movement through the ports 12, 14 of the plate heat exchanger 10. As used herein, the term “at least one target plate” refers to the plate or plates 16 that are located between the open end 128 and the closed end 130 of the distribution section 104, and which are the target of the cleaning fluid.

In some embodiments of the distribution section 104 shown in FIG. 4 the distribution section 104 has an open end 128 that is removably connected to the first end 114 of the fluid transfer section 102 via a flange 138 having a plurality of openings (not shown), a middle section 132 comprising a plurality of rods 140 and a closed end 130 comprising a disk 142 with a plurality of openings (not shown). The plurality of rods 140 extend through the plurality of openings both in the flange 138 and disk 142. The plurality of rods 140 can be held in place by a plurality of fasteners 146. While the embodiment in the figures shows the use of a plurality of cylindrical rods, it will be understood that the rods do not have to be cylindrical and can have any three-dimensional shape, for example, they can be cubed, or fin-shaped. In some embodiments, the plurality of rods have different shapes, while in other embodiments the plurality of rods have the same shape.

The plurality of rods 140 can be fixed in place, movable with respect to either the open end 128 or closed end 130 or movable with respect to both the open end 128 and the closed end 130. In some embodiments, the plurality of rods 140 can be movable through the plurality of openings 144 in the disk 142 and/or the flange 138.

In some embodiments, the plurality of fasteners 146 may be loosened and retightened, allowing for adjustment of the length of the distribution section 104. This gives the operator the ability to perform a more targeted cleaning of fewer plates 16 with a shorter distribution section 104 or to alternatively perform a less targeted cleaning of more plates with a longer distribution section 104.

When in use, the cleaning apparatus 100 is configured so that the length of the distribution section 104 corresponds to the number of plates 16 to be cleaned, and first part 106 of the fluid transfer section 102 is long enough for the distribution section 104 to reach the at least one target plate 16. The distribution section 104 and first part 106 of the fluid transfer section 102 are inserted into plate heat exchanger 10 through either to cold input port 12 or the hot input port 14 and the connecting section 110 removably attaches to the plate heat exchanger 10 to keep the cleaning apparatus 100 in position. When present, the sealing member 124 fluidly seals the connection between fluid transfer section 102 and the input port 12, 14. The second end 116 of the fluid transfer section 102 is connected to the apparatus what will pump cleaning fluid into the plate heat exchanger 10.

Cleaning fluid enters the cleaning apparatus 100 at the second end 116 of the fluid transfer section 102, travels through the fluid transfer section 102 and out the first end 114 of the fluid transfer section 102. The cleaning fluid enters the plate heat exchanger 10 by way of the distribution section 104. The length of the distribution section 104 can be altered so that there is targeted cleaning of the at least one target plate 16. Once the at least one target plate 16 have been cleaned, an operator can adjust the positioning of the distribution section 104 to target further plate(s) 6 to be cleaned. In some embodiments, the operator can use the handle 120 to move the fluid transfer section 102 to a second selection of at least one target plate 16. This process can continue until all the plates 16 have been cleaned. Alternatively, the operator may clean only some of the plates 16 of the plate heat exchanger 10, rather than all of the plates 16. In other embodiments, the number and order of plates 16 that are cleaned at a time can vary during the cleaning process depending on the requirements of the operator and the fouling of the plates 16. In some embodiments, the cleaning apparatus 100 is inserted into the other of the input ports 12, 14, so that the other side of the plates 16 can be cleaned.

In some embodiments of the cleaning method, the cleaning apparatus 100 may be configured such that distribution section 104 begins cleaning the plates 16 that are the farthest from the input channel 12, 14 openings and move towards the openings. Once the operator has determined that the region of plates have been sufficiently cleaned, fluid transfer section 102 may be moved relative to the connecting section 110, causing distribution section 104 to span a different section of plates 16.

As used herein the terms “a,” “an,” and “the” may include plural referents unless the context clearly dictates otherwise.

Although a few embodiments have been shown and described, it will be appreciated by those skilled in the art that various changes and modifications can be made to those skilled in the art that various changes and modifications can be made to these embodiments without changing or departing from their scope, intent or functionality. The terms and expressions used in the preceding specification have been used herein as terms of description and not of limitation, and there is no intention in the use of such terms and expressions of excluding equivalents of the features shown and described or portions thereof.