JP7220125B2 - Cleaning equipment and cleaning method - Google Patents

Description

Article 30, Paragraph 2 of the Patent Law applies Publication name: Hino Motors, Ltd. in-house newsletter Front Runner, Issue: No. 702, Page: Page 24, Date of issue: June 20, 2018, Publisher: Hino Motors, Ltd. (3-1-1 Hinodai, Hino-shi, Tokyo)

TECHNICAL FIELD The present invention relates to a cleaning apparatus and cleaning method for cleaning an exhaust purifier having a DPF.

Exhaust gases emitted from automobile diesel engines contain ash components such as calcium sulfate (CaSO ₄ ) in addition to particulate matter mainly formed from solid carbon. The ash component is trapped in the DPF along with the particulate matter and deposited within the cells of the DPF. In order to eliminate the clogging of DPF (Diesel Particulate Filter) due to the deposited ash component, it is necessary to remove the ash component.

Conventionally, cleaning is performed by physically removing the ash components by spraying a cleaning solution such as soapy water or water at high pressure onto the DPF on which the ash components are deposited (see, for example, Patent Document 1).

JP-A-2005-46729

However, the conventional method cannot remove the ash component to the extent that the performance of the DPF is sufficiently restored. In addition, when the ash component remains in the DPF, the ash component calcifies as it dries, resulting in malfunction of the DPF. Furthermore, when the cleaning time is long, the cleaning fluid such as soapy water or water is wasted.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to efficiently remove the ash component deposited on the DPF and to suppress wasteful consumption of the cleaning liquid.

In order to solve the above problems, a cleaning method for cleaning an exhaust purifier having an outer cylinder having a first opening on the diesel engine side and a second opening on the exhaust port side and a DPF housed in the outer cylinder The apparatus comprises a cleaning tank filled with a cleaning liquid obtained by dissolving a solubilizing component for solubilizing an ash component in water, and a state in which the exhaust purification device is immersed in the cleaning liquid in the cleaning tank. a circulation mechanism for circulating the cleaning liquid from the second opening through the DPF toward the first opening.

Further, a cleaning method for cleaning an exhaust gas purifier having an outer cylinder having a first opening on the diesel engine side and a second opening on the exhaust port side, and a DPF housed in the outer cylinder, wherein the ash component In a cleaning tank filled with a cleaning liquid obtained by dissolving a solubilizing component in water, the cleaning liquid is poured into the DPF through the second opening while the exhaust gas purifying device is immersed in the cleaning liquid. It is passed through and circulated toward the first opening.

According to the embodiment of the present invention, the ash component trapped in the DPF can be easily and efficiently removed by washing the DPF with a cleaning liquid containing the solubilized component. In addition, the circulation of the cleaning liquid promotes the dissolution and peeling of the ash component, so the removal efficiency of the ash component is high and the ash component hardly remains in the DPF. Moreover, since the cleaning liquid is circulated, wasteful consumption of the cleaning liquid can be suppressed.

It is sectional drawing of a washing|cleaning apparatus. It is a sectional view of a rinse device.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, although various technically preferable limitations are attached to the embodiments described below in order to carry out the present invention, the scope of the present invention is not limited to the following embodiments and illustrated examples.

<<<1. Exhaust purifier cleaning device >>>
FIG. 1 is a cross-sectional view of a cleaning device 10 that cleans an exhaust gas purifier 1. As shown in FIG.

The exhaust gas purifier 1 is provided in the middle of an exhaust pipe from a diesel engine of an automobile or the like. This exhaust gas purifier 1 is removed from the exhaust pipe and set in the cleaning device 10 . The exhaust gas purifier 1 has an outer cylinder 2 , a pre-stage filter 3 and a diesel particulate filter (hereinafter referred to as DPF) 4 . The outer cylinder 2 has a hollow and has a first opening 2a on the upstream side and a second opening 2b on the downstream side that communicate with the hollow. A flange 2 a is provided on the outer peripheral surface of the outer cylinder 2 . When this outer cylinder 2 is attached to the middle part of the exhaust pipe, the first opening 2a is on the side of the diesel engine, and the second opening 2b of the outer cylinder 2 is on the side of the exhaust port. The front-stage filter 3 is housed in the outer cylinder 2 near the first opening 2a on the diesel engine side, and the DPF 4 is housed in the outer cylinder 2 near the second opening 2b on the exhaust port side.

The front-stage filter 3 is a honeycomb-type DOC (Diesel Oxidation Catalyst) filter having a columnar outer shape. The front-stage filter 3 has a plurality of flow paths 3a extending from one end face to the other end face and arranged in a honeycomb shape, porous partition walls 3b partitioning the flow channels 3a, and porous partition walls 3b supported by the and an oxidation catalyst for diesel.

The DPF 4 is a honeycomb flow filter having a columnar outer shape. The DPF 4 includes a plurality of flow paths 4a extending from one end surface to the other end surface and arranged in a honeycomb shape, porous partition walls 4b partitioning the flow paths 4a, and the plurality of flow paths 4a arranged alternately. It has a plugging 4c that closes one end (inlet) of the flow path 4a, and a plugging 4d that closes the other end (outlet) of the remaining flow path 4a.

In addition to particulate matter (PM), which is mainly formed from solid carbon, ash components are also included in the gas discharged from diesel engines. The ash component is a salt containing one or more elements selected from Ca, Zn, P and S, such as calcium sulfate (CaSO ₄ ), calcium zinc phosphate (Ca ₁₉ Zn ₂ (PO ₄ ) ₁₄ ). Incidentally, Ca, Zn and P are derived from engine lubricating oil, and S is considered to be derived from fuel and engine lubricating oil. For example, _CaSO4 is the main component of gypsum and is sparingly soluble in water.

When the exhaust gas purifier 1 is used, the ash component is collected together with the particulate matter inside the channel 4a of the DPF 4 and deposited inside the channel 4a. The ash component deposited in the flow path 4a of the DPF 4 is physically difficult to remove, and is difficult to remove by washing with water only. By using this cleaning device 10 to clean the DPF 4 with the cleaning liquid 19, the ash component deposited in the flow path 4a can be simply and efficiently removed.

The cleaning device 10 includes a cleaning tank 11 , a seal plate 12 , a partition 13 , a circulation pump 14 , a suction pipe 15 , a supply pipe 16 and a strainer 17 . Here, the mechanism having the partition 13, the circulation pump 14, the suction pipe 15 and the supply pipe 16 is the circulation mechanism.

The cleaning tank 11 is provided in a box shape with an open upper surface. A cleaning liquid 19 is injected into this cleaning tank 11 .

The cleaning liquid 19 is an aqueous solution obtained by dissolving in water a component that solubilizes the ash component in water (hereinafter referred to as a solubilizing component). The solubilizing component is not limited as long as it serves to solubilize the ash component in water. is. Two or more of citric acid, citrate, ethylenediaminetetraacetic acid, and tartaric acid may be contained in the cleaning liquid 19 as a solubilizing component, and the cleaning liquid 19 is an aqueous citric acid solution, an aqueous citrate solution, an aqueous ethylenediaminetetraacetic acid solution, and tartaric acid. It may be a mixture of two or more selected from aqueous solutions. Some functional groups of these solutes capture Ca atoms or Zn atoms to form a complex compound, which becomes a water-soluble structure. Among them, the solubilizing component preferably contains citric acid or sodium citrate, or both, from the viewpoint of less toxicity and high removal effect. Although the concentration of the solubilizing component varies slightly depending on the number of functional groups of the solubilizing component, the valence of the metal in the ash component, etc., a concentration of 0.1 mol/l or more provides sufficient detergency. Other optional components may be added to the cleaning liquid 19 as long as the cleaning performance is not impaired. In the following description, it is assumed that the cleaning liquid 19 is an aqueous citric acid solution.

The partition 13 is placed on the seal plate 12 inside the cleaning tank 11 . The partition 13 is provided in a cylindrical shape with open upper and lower surfaces, and the lower opening of the partition 13 is closed by the seal plate 12 . When the lower end of the partition 13 is pressed against the seal plate 12 by the weight of the partition 13 and the exhaust gas purifier 1, the seal plate 12 is elastically deformed, thereby improving the liquid tightness between the lower end of the partition 13 and the seal plate 12. do. The partition 13 divides the space inside the cleaning tank 11 into a region 11 a inside the partition 13 and a region 11 b outside the partition 13 .

The outer cylinder 2 of the exhaust purification device 1 is fitted into the upper opening of the partition 13 with the second opening 2b facing the bottom inside the cleaning tank 11 . The outer peripheral surface of the outer cylinder 2 is in close contact with the inner peripheral surface of the partition 13, and a seal member may be provided between them. The outer cylinder 2 is supported by the partition 13 by the flange 2a of the outer cylinder 2 coming into contact with the upper end of the partition 13, and the lower end of the outer cylinder 2 is separated from the bottom inside the cleaning tank 11 upward. Therefore, a space surrounded by the partition 13 is formed between the DPF 4 and the inner bottom of the cleaning tank 11 . The cleaning liquid 19 is also present in that space.

By fitting the outer cylinder 2 into the partition 13 as described above, the first opening 2a of the outer cylinder 2 exists in the region 11b outside the partition 13, and the second opening 2b exists in the region 11a inside the partition 13. .

The exhaust cleaner 1 is immersed in the cleaning liquid 19 . Part of the exhaust gas purifier 1 protrudes from the liquid surface 19a of the cleaning liquid 19, and the first opening 2a is located above the liquid surface 19a.

The circulation pump 14 is installed outside the cleaning tank 11 . The suction pipe 15 extends from the circulation pump 14 to the outside of the partition 13 inside the washing tank 11 . The tip of the suction tube 15 is immersed in the washing liquid 19, and the strainer 17 is attached to the tip. A supply pipe 16 extends from the circulation pump 14 through the partition 13 and into the space 13a. Therefore, the area 11 a inside the partition 13 is supplied with the cleaning liquid 19 from which the soot and ash components have been removed by passing through the strainer 17 .

The circulation pump 14 sucks the cleaning liquid 19 outside the partition 13 through the suction pipe 15 and supplies the sucked cleaning liquid 19 to the inside of the partition 13 through the supply pipe 16 . The cleaning liquid 19 supplied to the inside of the partition 13 flows into the second opening 2b of the outer cylinder 2 of the exhaust purification device 1 by the pressure supplied by the circulation pump 14, passes through the DPF 4 in the outer cylinder 2 and the pre-stage filter 3. , from the first opening 2 a of the outer cylinder 2 . The cleaning liquid 19 flowing out from the first opening 2 a flows to the outside of the partition 13 inside the cleaning tank 11 . As described above, the cleaning liquid 19 is circulated.

Next, a method for cleaning the exhaust gas purifier 1 using the cleaning device 10 will be described.
First, water is poured into the washing tank 11, a solubilizing component (for example, citric acid) is added to the water, and the water is stirred to dissolve the solubilizing component in the water.

Next, the second opening 2b of the outer cylinder 2 is placed first, and the exhaust purification device 1 is fitted into the partition 13, and the flange 2a of the outer cylinder 2 is brought into contact with the partition 13. As shown in FIG.
Next, one end of the suction pipe 15 is connected to the circulation pump 14 and the strainer 17 is attached to the other end of the suction pipe 15 . One end of the supply pipe 16 is connected to the circulation pump 14 and the other end of the supply pipe 16 is connected to the partition 13 .
Next, a seal plate 12 is laid on the inner bottom of the cleaning tank 11 .
Next, the exhaust cleaner 1 and the partition 13 are immersed in the cleaning liquid 19 in the cleaning tank 11 with the second opening 2b of the outer cylinder 2 directed toward the inner bottom of the cleaning tank 11 . Then, the partition 13 is placed on the seal plate 12 . At this time, by adjusting the amount of the cleaning liquid 19 in the cleaning tank 11, part of the exhaust gas purifier 1 is not immersed in the cleaning liquid 19, and the second opening 2b of the outer cylinder 2 is positioned above the liquid surface 19a of the cleaning liquid 19. position above.
Next, the suction tube 15 and the strainer 17 are introduced into the washing liquid 19 outside the partition 13 .

Next, the circulation pump 14 is started. Then, the cleaning liquid 19 circulates through the cleaning tank 11, the strainer 17, the circulation pump 14, the partition 13, the DPF 4, the pre-stage filter 3, and the cleaning tank 11 in this order. As a result, the DPF 4 and the pre-stage filter 3 are backwashed with the washing liquid 19 .

The ash component deposited on the DPF 4 is solubilized by the solubilizing component in the cleaning liquid 19 . For example, the solubilizing component dissolved in the cleaning fluid 19 helps to solubilize the ash component in water by sufficiently reacting or forming complexes with compounds in the ash component. By solubilizing the ash component, the ash component dissolves in the solvent (water) in the cleaning liquid 19 or peels off from the DPF 4 . In particular, the flow of cleaning liquid 19 promotes dissolution and stripping of ash components.

The dissolved and peeled ash component flows together with the soot in the front-stage filter 3 , gushes out from the first opening 2 a of the outer cylinder 2 , and flows into the cleaning tank 11 . The ash component and soot that have not completely dissolved in the cleaning liquid 19 are collected by the strainer 17 . Therefore, as the circulation time of the cleaning liquid 19 progresses, the ash component and soot in the cleaning liquid 19 flowing out from the first opening 2a of the outer cylinder 2 decrease, and the turbidity of the cleaning liquid 19 becomes lighter.

During the circulation of the cleaning liquid 19, the cleaning liquid 19 flowing out from the first opening 2a of the outer cylinder 2 is observed. Then, when the turbidity of the cleaning liquid 19 flowing out becomes thin to the target concentration, the circulation of the cleaning liquid 19 is terminated by stopping the circulation pump 14 .

Next, the exhaust gas purifier 1 is removed from the cleaning liquid 19, and the cleaning liquid 19 adhering to the exhaust gas purifier 1 is removed.

Next, using the rinsing device 30 shown in FIG. 2, the DPF 4 and the pre-stage filter 3 of the exhaust purification device 1 are backwashed with water. The rinse device 30 will be specifically described below.

<<<2. Exhaust purifier rinsing device >>>
FIG. 2 is a cross-sectional view of a rinse device 30 for rinsing the exhaust purification device 1. As shown in FIG.
The rinse device 30 includes a waste liquid tank 31 , a sink 32 , casters 33 , a reversing table 34 , a guide 35 , a nozzle stand 36 , a spray nozzle 37 and a cover 38 .

The waste liquid tank 31 is provided in a box shape with an open upper surface.
A sink 32 is provided inside the waste liquid tank 31 and above the inner bottom of the waste liquid tank 31, and the space inside the waste liquid tank 31 is divided by the sink 32 into an upper area 31a and a lower area 31b of the sink 32. divided into The bottom of the sink 32 is provided with a drain hole 32a.

A guide 35 is provided horizontally and linearly on the upper portion of the inner wall of the waste liquid tank 31 . A reversing table 34 is attached to the guide 35 . The reversing table 34 is horizontally and linearly guided along the guide 35 . The reversing table 34 is rotatable about a horizontal axis perpendicular to the guide 35 . The exhaust cleaner 1 is attached to the reversing table 34 . A cover 38 is mounted on the exhaust gas purifier 1 so as to surround the outer cylinder 2 .

A nozzle stand 36 is attached to the upper portion of the waste liquid tank 31 . The nozzle stand 36 stands at a position on the one end 35 a side of the guide 35 and extends from above the edge of the upper opening of the waste liquid tank 31 toward above the center of the sink 32 . A spray nozzle 37 is provided downward at the upper end of the nozzle stand 36 . The spray nozzle 37 is arranged slightly closer to one end 35 a of the guide 35 than above the center of the sink 32 . The spray nozzle 37 uniformly sprays water downward.

Next, how to use the rinse device 30 will be described.
First, the reversing table 34 is moved to the other end 35b of the guide 35. Then, as shown in FIG.
Next, the exhaust gas purifier 1 is lifted above the sink 32 and attached to the reversing table 34 with the second opening 2b of the outer cylinder 2 facing the bottom of the sink 32 below.
Next, the exhaust gas purifier 1 is turned upside down by rotating the reversing table 34 together with the exhaust gas purifier 1 . Thereby, the second opening 2b of the outer cylinder 2 is directed upward.
Next, the cover 38 is lowered from the exhaust purifier 1, the outer cylinder 2 is fitted into the cover 38, and the cover 38 is brought into contact with the flange 2a of the outer cylinder 2. As shown in FIG. The cover 38 protrudes upward from the outer cylinder 2 , and the space above the second opening 2 b of the outer cylinder 2 is surrounded by the cover 38 .
Next, the reversing table is moved to one end 35 a of the guide 35 together with the exhaust gas purifier 1 . Then, the center of the second opening 2 b of the outer cylinder 2 is positioned right below the spray nozzle 37 .

Next, water is supplied to the spray nozzle 37 and sprayed from the spray nozzle 37 to the DPF 4 below. The water ejected from the spray nozzle 37 does not splash outside the cover 38, but the entire amount of the water is sprayed inside the cover 38. - 特許庁The sprayed water flows into the second opening 2b of the outer cylinder 2 of the exhaust purification device 1 by gravity, passes through the DPF 4 and the pre-filter 3 in the outer cylinder 2, and exits from the first opening 2a of the outer cylinder 2. It flows down to sink 32 . The water is stored in the lower region 31b of the waste liquid tank 31 through the drain hole 32a.

The solubilized ash component in DPF4 dissolves in water or peels off. The dissolved and peeled ash component flows together with the soot in the front filter 3 and flows down from the first opening 2 a of the outer cylinder 2 to the sink 32 . Therefore, as the washing time progresses, the ash component and soot in the water flowing out from the first opening 2a of the outer cylinder 2 decrease, and the turbidity of the water becomes lighter. During washing with water, observe the water flowing from the first opening 2a of the outer cylinder 2, and stop spraying the water when the water becomes almost transparent.

Next, the reversing table 34 is moved to the other end 35b of the guide 35, and the exhaust purifier 1 is removed from the reversing table 34. Then, water adhering to the exhaust gas purifier 1 is cut off and the exhaust gas purifier 1 is dried.

<<<3. Advantageous effects >>>
(1) By cleaning the DPF 4 with the cleaning liquid 19, the ash component deposited inside the flow path 4a of the DPF 4 can be removed simply and efficiently. In particular, since the flow of the cleaning liquid 19 promotes the dissolution and peeling of the ash component, the removal efficiency of the ash component is high and the ash component hardly remains in the DPF 4 .

(2) Since the cleaning liquid 19 is circulated, wasteful consumption of the cleaning liquid 19, especially the solubilized components, can be suppressed. Even if the cleaning liquid 19 is circulated, since the cleaning liquid 19 contains the solubilized component, it is possible to suppress a decrease in the removal efficiency of the ash component.

(3) Since the ash component and soot dispersed in the cleaning liquid 19 are collected by the strainer 17, even if the cleaning liquid 19 is circulated, most of the ash component and soot are present in the cleaning liquid 19 supplied into the partition 13. do not. Therefore, it is possible to prevent the separated ash component and soot from redepositing on the DPF 4 and the pre-filter 3 .

(4) Since the washing liquid during washing and the water during rinsing are made to flow from the DPF 4 toward the front filter 3 , soot in the front filter 3 can be prevented from entering the DPF 4 .

(5) Since the first opening 2a protrudes above the liquid surface 19a, it is possible to easily observe the suspended state of the cleaning liquid 19 flowing out from the first opening 2a.

(6) By washing the DPF 4 and the pre-filter 3 with water by the rinsing device 30, ash components and soot do not remain in the DPF 4 and the pre-filter 3. Also, when the exhaust gas purifier 1 is dried, the solubilized component, the ash component, and the like do not precipitate on the DPF 4 and the pre-stage filter 3 .

DESCRIPTION OF SYMBOLS 1... Exhaust gas purifier 2... Outer cylinder 2a... 1st opening 2b... 2nd opening 3... Pre-stage filter 4... DPF
DESCRIPTION OF SYMBOLS 10... Washing apparatus 11... Washing tank 12... Seal plate 13... Partition 14... Circulation pump 17... Strainer 19... Washing water 30... Rinsing apparatus 37... Spray nozzle

Claims (9)

A cleaning device for cleaning an exhaust gas purifier having an outer cylinder having a first opening on the diesel engine side and a second opening on the exhaust port side, and a DPF accommodated in the outer cylinder,
a cleaning tank filled with a cleaning liquid obtained by dissolving a solubilizing component in water to solubilize the ash component in water;
a circulation mechanism that passes the cleaning liquid from the second opening through the DPF and circulates the cleaning liquid toward the first opening while the exhaust purification device is immersed in the cleaning liquid in the cleaning tank;
cleaning equipment. The circulation mechanism is
a partition installed inside the cleaning tank, surrounding the second opening, and dividing the space in the cleaning tank into an inner area where the second opening exists and an outer area where the first opening exists;
2. The cleaning apparatus according to claim 1, further comprising a circulation pump that sucks the cleaning liquid in the outer area and supplies the cleaning liquid to the inner area. The partition is provided in a cylindrical shape having an opening, and the partition is installed on the inner bottom of the cleaning tank with the opening facing upward,
3. The cleaning device according to claim 2, wherein the outer cylinder is fitted into the opening of the partition with the second opening facing the inner bottom, and the outer cylinder is separated from the inner bottom. 4. The cleaning apparatus according to claim 3, wherein said first opening is positioned above the liquid surface of said cleaning liquid. 5. The cleaning according to any one of claims 2 to 4, further comprising a strainer that is introduced into the cleaning liquid in the outer region, is provided on the suction side of the circulation pump, and collects the ash component in the cleaning liquid. Device. 6. The cleaning device according to any one of claims 1 to 5, wherein said solubilizing component is one or more compounds selected from citric acid, citrates, ethylenediaminetetraacetic acid and tartaric acid. A cleaning method for cleaning an exhaust gas purifier having an outer cylinder having a first opening on the diesel engine side and a second opening on the exhaust port side, and a DPF housed in the outer cylinder,
Fitting the exhaust purifier into the partition with the second opening as the first,
In a cleaning tank filled with a cleaning liquid obtained by dissolving a solubilizing component for solubilizing an ash component in water, the second opening is directed toward the inner bottom of the cleaning tank, and the first opening is directed to the inner bottom of the cleaning tank. immersing a part of the exhaust purifier and the partition in the cleaning liquid so as to be above the liquid surface of the cleaning liquid;
A cleaning method in which the cleaning liquid is passed through the DPF from the second opening and circulated toward the first opening while the exhaust gas purifier and a part of the partition are immersed in the cleaning liquid . 8. The cleaning method according to claim 7, wherein after the circulation of the cleaning liquid, the water is sprayed to the second opening so that the water passes through the DPF from the second opening and flows to the first opening. The cleaning method according to claim 7 or 8, wherein the solubilizing component is one or more compounds selected from citric acid, citrates, ethylenediaminetetraacetic acid and tartaric acid.

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