JP6574662B2 - Washing system with heat exchanger through lint screen - Google Patents

Description

  The present invention newly applies an improved heat exchanger to a laundry system mainly used for business use, and in particular, a high-temperature cleaning in which lint (fiber waste) is largely removed in advance in such a heat exchanger. The present invention relates to a system using drainage.

In general, a washing machine or a washing system for business use can be efficiently washed by washing the washing liquid after raising the temperature.
FIG. 3 shows, as an example, an overview of the entire continuous laundry system using a counter flow type system. A plurality of washing tubs are arranged in order from the pre-washing tank shown on the left side in the figure, and each tub is provided in series with a rinsing tank and a finishing tank, and the objects to be washed are also moved to the right side sequentially. To do. On the other hand, the washing liquid (cleaning liquid) performs efficient washing by flowing through each of these tanks so as to run against the flow of the washing object.

As described above, it is possible to improve the cleaning efficiency by increasing the temperature of the cleaning liquid, but it is around 60 degrees Celsius for general use such as linen, but because of the necessity of sterilization for medical institutions such as hospitals. Cleaning is performed at around 80 degrees Celsius.
Since these cleaning liquids are always used and consumed in large quantities, it is desired to save fuel necessary for increasing the temperature of the newly supplied normal temperature cleaning liquid. Specifically, clean cleaning liquid (new liquid) that is newly supplied and dirty cleaning drainage that is discharged at a high temperature are always present. By using the heat of the liquid to increase the temperature of the new liquid, it is possible to greatly save the fuel required for increasing the temperature of the new liquid.

JP 2010-210402 A JP 2006-325680 A

However, by washing the article to be washed, a large amount of lint is mixed in the washing liquid. A large amount of this lint floats in the drainage under high temperature conditions. Therefore, if the used high-temperature cleaning liquid is poured into the heat exchanger as it is, the heat exchanger will be clogged. Every time clogging occurs, the operation of the entire washing system is stopped, and clogging removal work is required. Therefore, not only maintenance work is required, but also the cleaning operation is forced to be interrupted as a whole. It is desirable that such work interruptions be as few as possible.
In order to solve this problem, Japanese Patent Application Laid-Open No. 2010-214022 proposes a heat exchanger that rotates a disk-shaped rotating body that serves as a heat transfer surface. This is a heat exchanger in which lint adhesion is prevented by centrifugal force or the like by rotation of the disk. Although this technique is useful as it is, the shape of the heat exchanger is complicated and the manufacturing cost is increased. In addition, when clogging occurs inside, clogging removal work becomes extremely difficult. In the first place, clogging due to lint is a problem specific to heat exchangers used in laundry systems that are often used for business purposes, so heat exchangers may be simple structures for convenience of design changes. desirable.

  Moreover, as shown in the above-mentioned Japanese Patent Application Laid-Open No. 2006-325680, there is a technique specialized in automatically removing lint in used cleaning waste liquid. By using an apparatus according to this technique (hereinafter referred to as “lint screen”), about 90% of lint in the drainage can be removed. However, complete lint removal is still impossible. Therefore, even if it is a high temperature washing drainage liquid from which a considerable amount of lint has been removed by a lint screen, it is not a desirable solution to pour the drainage liquid into a heat exchanger that uses a curved pipe. However, in the case of the cleaning drainage liquid from which a considerable amount of lint has been removed, a phenomenon that lint accumulates in the straight pipe and causes clogging does not occur.

Under such circumstances, the present inventors applied the straight pipe type heat exchanger shown in FIG. 4 to the high-temperature washing drainage liquid from which about 90% of lint was previously removed by a lint screen.
Here, the high temperature washing drainage flowing into the heat exchanger from the drainage inlet pipe 14 on the left side in FIG. 4 flows to the right side while exchanging heat in the narrow pipe, and then flows out from the drainage outlet pipe 15. As shown in the figure, when the high temperature washing drainage is introduced from the direction parallel to the axial center of the heat exchanger, a large amount of drainage flows unevenly into the narrow pipe near the drainage inlet pipe 14. Has occurred. In addition, fine lint was accumulated while being entangled at the entrance of each narrow tube, and the narrow tube was clogged after continuous operation for about 3 days. Therefore, cleaning work is required at least once every two days, which is a problem in practical application.

  Therefore, the present invention has been made in view of such circumstances, and aims to save energy while simultaneously reducing energy consumption while suppressing work interruptions due to clogging of lint and passing through a lint screen. It is an object of the present invention to provide a washing system including a heat exchanger using high-temperature washing drainage.

  As a result of diligent research in view of the above problems, the present inventors have made a trial and error with respect to a heat exchanger into which high-temperature washing drainage liquid that has passed through a lint screen in advance, and as a result, it is possible to dramatically reduce the clogging frequency. It came to invent the structure of a heat exchanger. Moreover, even if clogging occurs, it has succeeded in producing a structure that can be easily removed.

That is, a plurality of straight tube-type thin tubes that conduct high-temperature washing drainage that has passed through a lint screen in advance are provided inside, and penetrate through the conductive portions of the thin tubes that are alternately arranged along the axial direction of the heat exchanger. Each capillary is bundled together by a baffle with a hole and a shape surrounded by an arc and a string,
It is a straight tube type heat exchanger that performs heat exchange by passing a new liquid from the other end side to the remaining gaps between each thin tube and baffle,
At both ends of the heat exchanger, a space that is not blocked by the thin tube is formed and a new liquid inlet / outlet tube is provided at a position blocked by a spacer adjacent to the space,
Provided in the two spaces is a washing system having a heat exchanger through a lint screen, wherein the drainage inlet / outlet pipe is provided in an arbitrary vertical direction of the axial direction of the heat exchanger. .
By adopting such a configuration, in the space portion that is not obstructed by the thin tube, vortex flow due to drainage occurs, and it becomes possible to greatly reduce clogging due to lint accumulation, It is possible to obtain a washing system including a heat exchanger that has passed through a lint screen that allows efficient heat exchange with no waste liquid flow.

When the clogging due to lint occurs, the cleaning operation by backwashing is performed by causing the space formed on both sides of the heat exchanger, which is not obstructed by the thin tubes, to flow back through the thin tubes. A washing system comprising a heat exchanger through the lint screen according to claim 1 is provided.
By adopting such a configuration, even if clogging occurs at the entrance of each thin tube due to lint, backwashing work can be performed by performing backwashing. In order to prevent new clogging due to such back washing operation, the heat exchanger is formed with the space portions at both ends, and the outlet side of the drainage is also in any vertical direction in the axial direction of the heat exchanger. The eddy current is generated by preparing for.

Each of the capillaries is made of stainless steel, the outer diameter thereof is in the range of 10 to 23 [mm], and the tube wall thickness of each capillaries is 0.3 to 1.7 [mm]. Features a washing system with a heat exchanger through a lint screen.
By adopting such a configuration, it is possible to effectively prevent clogging due to lint inside the heat exchanger and to secure a minimum level of heat conduction while ensuring a minimum level of strength.

In addition, the heat exchanger is arranged in parallel, connecting the inlet and outlet pipes between adjacent heat exchanger end portions to form a flow path in a series type as a whole, the washing drainage and the A washing system including a heat exchanger through a lint screen is used, in which a new cleaning liquid flows through the series-type flow paths from opposite sides.
By adopting such a configuration, it becomes possible to effectively use the dead space in the washing system, and it is possible to perform heat exchange with a very high efficiency, which is substantially the same as lengthening the heat exchanger.

Further, the drainage inlet / outlet pipe has a range (more preferably 3 to 16 degrees) with an inclination of 3 to 47 degrees with respect to the center point from any one point on the outer peripheral surface perpendicular to the center axis of the heat exchanger. A washing system equipped with a heat exchanger through a lint screen is used.
By adopting such a configuration, many vortex flows in the disturbance chamber of the heat exchanger are generated, and the effect of preventing clogging by lint is further enhanced.

It is a schematic diagram showing an example of the whole washing system concerning this embodiment. It is a figure which shows an example of the whole structure of the heat exchanger concerning this embodiment. It is a schematic diagram which shows an example of the whole conventional washing system. It is a figure which shows the whole structure of the conventional heat exchanger.

Hereinafter, a first embodiment of a washing system including a heat exchanger using high-temperature washing drainage liquid that has passed through a lint screen according to the present invention will be described with reference to the accompanying drawings.
FIG. 1 shows a schematic diagram of a counter flow type system as an example of the entire washing system according to the present embodiment. Although the extraction location of the high temperature washing drainage is different for each system, in this embodiment, as an example, the washing drainage from the first washing tub is poured into the heat exchanger via the lint screen. In this heat exchanger, after the heat exchange between the new liquid at room temperature newly supplied from a spare tank such as a prewash liquid tank outside the system or inside the system and the high temperature washing waste liquid, Is discharged outside the system.

  FIG. 2 is a diagram illustrating an example of the overall structure of the heat exchanger according to the present embodiment. As the heat exchanger according to the present embodiment, a cylindrical straight tube heat exchanger 1 in which a large number of thin tubes are bundled inside an outer tube is applied. The reason for using a straight pipe type heat exchanger is that, as described above, the cleaning waste liquid from which a certain amount of lint has been removed by a lint screen is contaminated inside the straight pipe that is not a curved pipe, which causes clogging of the pipe. This is due to the fact that it is difficult for sediment to form.

In addition, since it is a heat exchanger that has a particular problem with laundry systems that are often used for business purposes, such as clogging due to lint, the size must be included so that it can be accommodated in the dead spaces that exist throughout the laundry system. Therefore, it is desirable that it is a straight pipe type in which the design change of the entire structure is easy. The fact that it is not necessary to provide a new space for the heat exchanger in the washing system is a great advantage in practical application.
In the present embodiment, as an example, the lint screen introduced in the above-mentioned Japanese Patent Application Laid-Open No. 2006-325680 is applied. However, if the lint screen has a function capable of removing a certain amount of lint, it is particularly necessary to limit to this lint screen. There is no. For example, even a chemical method in which lint is aggregated and precipitated in advance with respect to high temperature drainage falls under the lint screen in the present invention.

First, the high-temperature washing drainage liquid that has been largely lint-removed by the lint screen flows through the drainage inlet pipe 4 into the disturbance chamber 2 that is not obstructed by the narrow pipe. That is, the hot washing drainage is flowed from an arbitrary vertical direction in the axial direction of the heat exchanger 1.
The scrubbing effluent in the high temperature state is turbulent in the disturbing chamber 2 and becomes a vortex, and then flows into each capillary as shown by the arrows in the figure, while flowing through each capillary from the left side to the right side in the figure, Heat is supplied to a new cleaning liquid in a normal temperature state to be described later, and after flowing through the disturbance chamber 3, the liquid flows out from the drain outlet pipe 5. On the other hand, the normal temperature new liquid flowing from the new liquid inlet pipe 6 flows through the gaps other than the narrow pipes and flows into the heat exchanger 1 from the right side to the left side in the figure, so that the high temperature drainage liquid in each narrow pipe is obtained. Heat is received from the liquid and flows out from the new liquid outlet pipe 7. Unlike the waste liquid, the normal temperature new liquid is a clean liquid that does not contain lint, so there is less risk of clogging, but when dirt accumulates over long periods of time, it is washed with chemicals. It is necessary.

  In the case of using this heat exchanger 1 that uses high-temperature washing drainage that has been largely lint removed in advance by a lint screen, the disturbance chamber is passed through the drainage inlet pipe 4 from any vertical direction in the axial direction of the heat exchanger 1. The phenomenon that the vortex is efficiently generated is caused by being flown into the air. Therefore, the accumulation by the lint which grows when the fine fiber scraps are entangled with each other at the entrance of each narrow tube tube is prevented in advance by the eddy current, and the cleaning work due to clogging is extremely reduced. At present, the test is continuously performed for about 5 months, but clogging has never occurred.

  On the other hand, when high-temperature washing drainage is flowed in the axial direction and the horizontal direction of the heat exchanger shown in FIG. 4, vortices are not generated in the disturbance chamber, and the uneven flow into a part of the narrow tube Unevenness occurs, and the heat exchange efficiency of the heat exchanger 1 as a whole is greatly impaired. It is a very great effect that such inflow unevenness does not occur in the heat exchanger 1 in the present embodiment. Further, in the heat exchanger shown in FIG. 4, since no vortex is generated, lint accumulates at the capillary tube inlet (particularly in the vicinity of the drainage inlet tube 14), and the capillary tube inlet is eventually clogged. Cleaning work by backwashing work becomes necessary once a day.

  Here, the backwashing operation is an in-pipe cleaning operation in which the flow of the cleaning waste liquid in the heat exchanger 1 is made to flow backward, and the lint that has clogged in the vicinity of the inlet of each narrow tube on the disturbance chamber 2 side is removed. Work. In addition, due to the nature of the cleaning work, in some cases, not only drainage but also clean liquid may be used, and in order to remove dirt deposits due to long-term use (generally several years) such as dirt, The drug may be mixed into the liquid. Even in such backwashing work, in order to prevent clogging due to lint in the event of applying drainage, the heat exchanger 1 according to the present embodiment is provided with not only the disturbance chamber 2 but also the disturbance chamber 3. It is desirable to generate a vortex by providing the drain outlet pipe 5 in an arbitrary vertical direction in the axial direction of the heat exchanger 1. In addition, the presence of the disturbance chamber 3 is an essential component in the second embodiment of the present invention described later.

Here, in order to increase the heat exchange efficiency of each thin tube, the thinner the heat transfer plate that separates the high-temperature fluid and the low-temperature fluid, the better. However, the thinness causes a decrease in strength. Therefore, in this embodiment, stainless steel thin tubes having various thicknesses were prepared and tested. The minimum required tube wall thickness varies depending on various conditions such as temperature and pressure fluctuations of the washing drainage. However, at least 0.3 [mm] is necessary from the viewpoint of ensuring an average safe strength characteristic in the heat exchanger 1 of the present embodiment. On the other hand, the heat transfer characteristics deteriorate due to an increase in the thickness of the tube wall. As the heat exchanger 1 of the present embodiment, the upper limit thickness of the thin tube wall for realizing beneficial heat exchange was 1.7 [mm].
From the above experimental results, the condition is that the tube wall thickness of the stainless steel thin tube used for the heat exchanger 1 is 0.3 [mm] to 1.7 [mm].
On the other hand, the outer diameter of each thin tube according to the present embodiment, which prevents clogging after generating vortex, is effective in preventing clogging in the range of 10 [mm] to 23 [mm] on the premise of the above-mentioned tube wall thickness. Was remarkable.

  In addition, it is difficult to maintain a uniform flow rate of the new liquid flowing through the gap where each thin tube does not exist in the heat exchanger 1 in each cross section of the heat exchanger 1. Since such uneven flow rate also adversely affects heat exchange efficiency, it is necessary to provide a baffle 8 that is a plate having a thin tube portion penetrated. Here, in order not to completely block the flow of the new liquid, the baffle 8 uses a plate surrounded by an arc and a string. In this embodiment, as shown in FIG. 2, by arranging the baffles 8 alternately, the flow of the new liquid is induced to prevent uneven flow and improve the heat exchange efficiency. By guiding the flow path long so that it flows in a zigzag shape, the amount of heat received by the new liquid from the high-temperature drainage in each capillary tube is increased. That is, the heat exchange efficiency is improved.

  In addition, the specific diameter of the entire heat exchanger 1 varies depending on the flow rate of the liquid to be heat exchanged, but it can be freely designed according to the size of the dead space existing in various places in the entire washing system. Is possible. As for the specific length of the heat exchanger 1 in the axial direction, the longer the heat length, the larger the amount of heat to be exchanged, which is ideal. However, as described above, a free design considering the balance with dead space. Is desirable. An embodiment for solving this point and further improving the heat exchange efficiency will be described later.

  Moreover, about the internal shape of the disturbance chambers 2 and 3, by installing the drainage inlet pipe 4 in the arbitrary vertical direction of the axial direction of the heat exchanger 1, the disturbance of the flow is sufficiently generated and the generation of the vortex is caused. I was able to confirm. Moreover, the flow rate unevenness of the high-temperature drainage flowing into the narrow tube did not occur. Therefore, there is no problem as long as the disturbing chambers 2 and 3 are spaces that are not obstructed by the narrow tubes even if specific dimensions are not determined.

The disturbing chambers 2 and 3 are each provided with a spacer, which is a partition wall, on the central side of the heat exchanger 1 so as to completely shut off the washing waste liquid and the new liquid. A pipe 7 and a new liquid inlet pipe 6 are provided. With such a blocking structure, the cleaning drainage fluid communicates between the disturbance chambers 2 and 3 by conducting the inside of the narrow tube through a large number of holes formed in the spacer without intersecting with the new fluid.
By applying such a heat exchanger 1, the dead space existing in various places in the entire washing system can be effectively used, and the downsizing of the entire washing system is never impaired, and clogging of the thin tubes due to lint is possible. Without interrupting the operation, it is possible to obtain a high heat exchange rate with no flow unevenness for both the new liquid and the drained liquid. Thus, a significant energy saving effect can be realized.

Next, a second embodiment of the present invention will be described.
As described above, in order to increase the heat exchange amount, it is desirable that the overall length of the heat exchanger 1 is longer. However, from the viewpoint of effective use of dead space, it is not practical in design to lengthen the heat exchanger 1 by one. Therefore, as a whole, the inlet and outlet pipes at the other ends of the adjacent heat exchangers 1 are connected to each other so that the liquid flows in series while arranging a plurality of heat exchangers 1 in parallel. A serial flow path may be formed.

For example, when two pipes are arranged in parallel, the cleaning waste liquid is poured from one end of one heat exchanger, and the new liquid is poured from one end of the other heat exchanger, and each inlet is connected to the other end of both heat exchangers. By connecting the pipe and the outlet pipe to each other with new liquids and waste liquids, the same effect as that of effectively lengthening the heat exchanger 1 can be obtained. At the same time, a free design according to the shape of the dead space existing in various places in the washing system becomes possible, which is very useful for effective use of the dead space. From the viewpoint of preventing clogging due to lint, a maximum of four, preferably three, are arranged in parallel. In the present embodiment, the presence of the disturbance chamber 3 in the heat exchanger 1 is essential for preventing clogging caused by lint.
By adopting such a configuration, it is possible to dramatically improve the heat exchange rate while effectively utilizing the dead space.

  Moreover, when installing a washing system in a basement, in order to prevent the heat loss from the heat exchanger 1 and piping, it may be necessary to heat-insulate the heat exchanger 1 and each piping. The heat loss may be prevented by various heat insulation methods such as applying or spraying a material to be a heat insulating material. The simplest practical method is a method of winding each pipe with a urethane or styrene foam sheet. Also by this, the heat loss prevention effect of about 5% can be expected.

Next, a third embodiment of the present invention will be described.
As described above, a phenomenon in which the flow is disturbed occurs when high-temperature cleaning drainage is poured into the disturbance chamber 2 or 3 from an arbitrary vertical direction in the axial direction of the straight-tube heat exchanger 1. However, when the drainage inlet pipe 4 was slightly inclined and then flowed in, the flow was more disturbed and many vortices were generated.

Specifically, on the cross-sectional circle perpendicular to the axis of the heat exchanger 1, the contact point of the center of the cross-section of the drainage inlet pipe 4 located on the circumference of the cross-section and the center point of the circle When the angle toward the center point of the circle is set to 0 degree, when the drainage inlet / outlet pipe 4 is sequentially changed from 0 degree to nearly 90 degrees around the contact point, the cleaning drainage liquid is poured, In the viscosity of the high-temperature drainage liquid in this embodiment, a very large amount of vortex generation was observed in the angle range of 3 to 47 degrees. Further, depending on the flow rate condition and the temperature condition, further vortex generation was confirmed at 3 to 16 degrees.
From such observation results, the drainage inlet pipe 4 is tilted within a range of 3 to 47 degrees with respect to the center point on a cross-sectional circle perpendicular to the center axis of the heat exchanger 1, and fixed by welding means or the like. In addition, an effect of further enhancing the clogging prevention effect due to lint deposition can be obtained.

  As described above, the present invention is a useful washing system for solving problems such as clogging due to lint when a newly supplied clean liquid is heated to a high temperature in a heat exchanger in a washing system using a cleaning liquid at a high temperature. is there. The laundry system used in the present invention is generally a large number of commercial laundry systems. However, the present invention is not limited to a commercial laundry system, but can be widely applied to a laundry system having a heat exchanger having a unique problem of clogging due to lint.

  The laundry system including the heat exchanger that has passed through the lint screen of the present invention can be widely used not only for business purposes but also in the entire laundry industry using a high-temperature cleaning liquid and a heat exchanger.

1: Heat exchanger 2, 3: Disturbing chamber 4: Drainage inlet pipe 5: Drainage outlet pipe 6: New liquid inlet pipe 7: New liquid outlet pipe 8: Baffle 14: New liquid inlet pipe 15: Drainage outlet pipe

Claims (5)

A plurality of straight tube-type tubules that conduct high-temperature washing drainage that has passed through a lint screen in advance are provided inside, and through holes are formed in the conduction portions of the tubules arranged alternately along the axial direction of the heat exchanger. Each thin tube is bundled together by a baffle with a shape surrounded by an arc and a string,
It is a straight tube type heat exchanger that performs heat exchange by passing a new liquid from the other end side to the remaining gaps between each thin tube and baffle,
At both ends of the heat exchanger, a space that is not blocked by the thin tube is formed and a new liquid inlet / outlet tube is provided at a position blocked by a spacer adjacent to the space,
The washing system having a heat exchanger through a lint screen, wherein both the spaces are provided with an inlet / outlet pipe for the drainage liquid in an arbitrary vertical direction of the axial direction of the heat exchanger.   When the clogging due to lint occurs, the cleaning operation by backwashing is performed by causing the space formed on both sides of the heat exchanger, which is not obstructed by the thin tubes, to flow back through the thin tubes. The washing system provided with the heat exchanger which passed through the lint screen of Claim 1.   Each of the thin tubes is made of stainless steel, the outer diameter thereof is in the range of 10 to 23 [mm], and the tube wall thickness of each of the thin tubes is 0.3 to 1.7 [mm]. A washing system comprising a heat exchanger through the lint screen according to claim 1 or 2.   The heat exchanger is arranged in parallel, and an inlet / outlet pipe is connected between adjacent end portions of the heat exchanger so as to form a flow path in a series type as a whole. The laundry system having a heat exchanger through the lint screen according to any one of claims 1 to 3, wherein the series-type flow paths flow from opposite sides to each other.   The drainage inlet / outlet pipe is arranged in a range having an inclination of 3 to 47 degrees with respect to the center point from any one point on the outer peripheral surface perpendicular to the center axis of the heat exchanger. The washing system provided with the heat exchanger which passed through the lint screen of any one of Claims 1-4.