JP2005248824A - Urea water thawing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a urea water thawing device capable of properly and sufficiently thawing a solution frozen in a tank main body. <P>SOLUTION: This urea water thawing device is provided with the tank main body 10 storing a solution, a floating body 12 floating in the tank main body 10 by the solution, an absorbing means 13 arranged in the floating body 12 to absorb the solution, and a heating means 14 arranged in the floating body 12 to thaw the solution frozen in the tank main body 10. Consequently, since the heating means 14 is stably arranged on a horizontal face in the tank main body 10, the floating body 12 also lowers in accordance with reduction of liquid level due to absorption of the solution when thawing and absorbing the frozen solution to thaw the solution frozen in the tank main body 10 properly and sufficiently. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a urea water thawing device for thawing and sucking a frozen solution.

  Conventionally, diesel engine vehicles are equipped with a NOx reduction catalyst (selective reduction catalyst) that has the property of selectively reacting NOx with a reducing agent even in the presence of oxygen in the middle of an exhaust pipe through which exhaust gas flows. The required amount of reducing agent is added to the upstream side of the NOx reduction catalyst to cause the reducing agent to undergo a reduction reaction with NOx (nitrogen oxide) in the exhaust gas on the NOx reduction catalyst, thereby reducing the NOx emission concentration. There is something that can be done.

  For example, as this type of NOx reduction catalyst, noble metal catalysts such as platinum and palladium and base metal catalysts such as vanadium, copper and iron oxides are already known as having the above-mentioned properties.

In the field of industrial flue gas denitration treatment in plants and the like, the effectiveness of a method of reducing NOx using ammonia (NH ₃ ) as a reducing agent is already well known. It is considered to use urea water as a reducing agent.

  When actually using urea water as a reducing agent, the urea water is supplied from the urea water thawing device to the injection nozzle via the supply pump so that the urea water can be injected from the injection nozzle upstream of the NOx reduction catalyst. The urea water thawing device is configured to store a predetermined amount of urea water.

  Here, as shown in FIG. 5, the urea water thawing device 1 will be specifically described. The urea water thawing device 1 includes a tank body 4 including a container portion 2 and a lid portion 3, and a container penetrating the lid portion 3. The suction pipe 5 extends to the vicinity of the lower surface of the portion 2 and a nichrome wire heater 6 wound around the suction pipe 5. The urea water N is sucked from the suction pipe 5.

  On the other hand, since the urea water N freezes at a predetermined temperature or lower, when it freezes, it is heated by the heater 6 so that the urea water N can be sucked.

In addition, about what was equipped with such urea water thawing | decompression apparatus, there exist some which were already equipped in the exhaust gas purification apparatus which purifies exhaust_gas | exhaustion (for example, refer patent document 1).
JP 2002-161732 A

  However, when the heater 6 is used in the conventional urea water thawing apparatus 1 along with the freezing of the urea water N, only the periphery of the heater 6 is thawed out of the frozen urea water N as shown in FIGS. However, since the portion away from the heater 6 is not thawed, there is a problem that the urea water N is insufficient although there is sufficient urea water N in the tank body 4.

  The present invention has been made in view of the above-described circumstances, and an object thereof is to provide a urea water thawing device capable of thawing a solution frozen in a tank body appropriately and sufficiently.

  According to a first aspect of the present invention, there is provided a tank main body for storing a solution, a float body floating by the solution in the tank main body, a suction means disposed in the float body for sucking the solution, and a tank disposed in the float body. The present invention relates to a urea water thawing device comprising heating means capable of thawing a solution frozen in the body.

  According to a second aspect of the present invention, there is provided the urea water thawing device according to the first aspect, comprising a guide bar for guiding the moving direction of the float body.

  A third aspect of the present invention relates to the urea water thawing device according to the first or second aspect, wherein the suction means and the heating means are combined into a heat hose.

  A fourth aspect of the present invention relates to the urea water thawing device according to any one of the first to third aspects, wherein the heating means is arranged around the lower part of the float body.

  A fifth aspect of the present invention relates to the urea water thawing device according to any one of the first to fourth aspects, wherein the heating means is disposed so as to protrude from the outer periphery of the float body.

  Thus, according to the present invention, the heating means is provided in the float body so that the heating means is arranged large and stably on the horizontal surface in the tank body, so when thawing and sucking the frozen solution, As the liquid level decreases due to the suction of the solution, the float body also descends, and the solution frozen in the tank body can be thawed appropriately and sufficiently, and as a result, the urea water shortage can be prevented.

  When a guide rod that guides the moving direction of the float body is provided, the float body is surely lowered to a predetermined position by the guide rod as the liquid level decreases, so that the solution frozen in the tank body is more appropriately thawed. be able to.

  When the suction means and heating means are combined into a heat hose, the frozen solution around the suction means is thawed by the heating means, so that the solution can be easily sucked and the frozen solution in the tank body can be thawed more appropriately. Can do.

  Placing the heating means around the float body thaws the frozen solution below the float body, so the effect of the frozen solution below the float body is eliminated and the float body is moved downward. Smoothly, the solution frozen in the tank body can be thawed more appropriately.

  When the heating means is arranged so as to protrude from the outer periphery of the float body, the frozen solution on the outer periphery of the float body is thawed, so the effect of the frozen solution around the float body is eliminated and the downward movement of the float body is smooth. Thus, the solution frozen in the tank body can be thawed more appropriately and in a large amount.

  As described above, according to the urea water thawing device of the present invention, since the heating means is provided in the float body so that the heating means is arranged large and stably on the horizontal surface in the tank body, the frozen solution is thawed. As the liquid level drops due to the suction of the solution, the float body also descends, and the solution frozen in the tank body can be thawed appropriately and sufficiently.

  Embodiments of the present invention will be described below with reference to the drawings.

  1 is a schematic diagram showing a urea water thawing device of the present invention, FIG. 2 is a schematic diagram showing the arrangement of a heat hose as viewed in the direction of II-II in FIG. 1, and FIG. 3 is a urea water thawing device of the present invention. FIG. 4 is a schematic view showing a state in which the frozen urea water is started to be thawed in FIG. 4, and FIG. 4 is a schematic view showing a state in which the frozen urea water is thawed and sucked in the urea water thawing device of the present invention.

  The urea water thawing device 7 according to this embodiment includes a tank body 10 including a container portion 8 and a lid portion 9 so as to store urea water N, and a guide rod that extends through the lid portion 9 to the vicinity of the lower surface of the container portion 8. 11, a float body 12 slidably inserted in the guide rod 11 and floated by urea water N, a hose-like suction means 13 attached to the lower surface of the float body 12, and a heating means 14 such as a nichrome wire. .

  Here, the float body 12 includes a disk-shaped upper portion 15 having a large area on the horizontal surface of the tank body 10 and an inverted conical lower portion 16 formed from the periphery of the disk-shaped upper portion 15 toward the lower center. In addition, a through hole 17 in which the guide rod 11 is positioned is provided at the axial center position of the float body 12 so as to penetrate from the approximate center of the disk-shaped upper portion 15 to the apex of the inverted conical lower portion 16. The material and specific gravity of the float body 12 are not particularly limited as long as they float on the urea water N.

  The suction means 13 and the heating means 14 are combined into one heat hose 18 by incorporating the heating means 14 such as a nichrome wire in the thick portion of the hose-like suction means 13 in the tank body 10. The heat hose 18 circulates in a spiral shape so as to spread from the leading inlet 19 disposed near the lowermost end of the float body 12 to the inverted conical lower portion 16 of the float body 12 stably. Furthermore, it is attached to the periphery 15a of the disk-shaped upper part 15 so that it may protrude from the outer periphery of the float body 12. FIG. Further, the heat hose 18 extends from the float body 12 with a predetermined length without contacting the guide rod 11 so as not to affect the movement of the float body 12, and the supply pump is provided outside the tank body 10. (Not shown).

  The operation of the embodiment for carrying out the present invention will be described below.

  When the urea water N in the tank body 10 is used for exhaust gas purification or the like, a supply pump (not shown) is driven to suck the urea water N from the heat hose 18 to an ejection nozzle (not shown) or the like. At this time, the liquid level of the urea water N is lowered by the suction of the urea water N, and the float body 12 is lowered at the same time. Conversely, when supplying the urea water N into the tank body 10, it is supplied from the introduction destination via the heat hose 18 or the like, and at this time, the level of the urea water N rises due to the supply of the urea water N. At the same time, the float body 12 is lifted.

  On the other hand, when the urea water N in the tank body 10 freezes at a predetermined temperature or lower and the urea water N is used for exhaust purification in the frozen state, the urea water N is heated by the heating means 14 of the heat hose 18. Then, the urea water N is sucked by the suction means 13 of the heat hose 18 and fed to a jet nozzle (not shown) or the like. At the same time, the float body 12 descends as the liquid level decreases due to the suction of the urea water N, and the heating means 14 and the suction of the heat hose 18 so that the frozen urea water N can be continuously thawed and sucked. The means 13 is brought close to the frozen aqueous urea N below.

  Next, in the tank body 10, when the float body 12 reaches the vicinity of the bottom surface of the tank body 10, the thawing and suction of the urea water N is completed, and finally most of the frozen urea water N is thawed. Can be aspirated.

  As described above, according to the present embodiment, the heating means 14 is provided on the float body 12 so that the heating means 14 is disposed large and stably on the horizontal plane in the tank body 10, so that the frozen urea water N is thawed. In the suction, the float body 12 also descends as the liquid level decreases due to the suction of the urea water N, and the urea water N frozen in the tank body 10 is defrosted appropriately and sufficiently, resulting in urea. A shortage of water N can be prevented.

  When the guide rod 11 for guiding the moving direction of the float body 12 is provided, the float body 12 is surely lowered to a predetermined position by the guide rod 11 as the liquid level is lowered. N can be thawed more appropriately. Further, even when the level of the urea water N rises due to the supply of the urea water N, the float body 12 can be reliably lifted to a predetermined position by the guide rod 11.

  If the suction means 13 and the heating means 14 are combined into a heat hose 18, the frozen urea water N around the suction means 13 is thawed by the heating means 14, so that the urea water N can be easily sucked and the float body 12 The movement can be made smooth, and the urea water N frozen in the tank body 10 can be thawed more appropriately.

  If the heating means 14 is arranged around the lower portion 16 of the float body 12, the frozen urea water N below the float body 12 is thawed, so the influence of the frozen urea water N below the float body 12 is eliminated. Thus, the downward movement of the float body 12 can be made smooth, and the urea water N frozen in the tank body 10 can be thawed more appropriately.

  If the heating means 14 is disposed so as to protrude from the outer periphery of the float body 12, the frozen urea water N on the outer periphery of the float body 12 is thawed, so that the influence of the frozen urea water N around the float body 12 is eliminated to float. The downward movement of the body 12 can be made smooth, and the urea water N frozen in the tank body 10 can be thawed more appropriately and in a large amount.

  The urea water thawing device of the present invention is not limited only to the above-described embodiment. The solution put into the tank body is not limited to urea water, and the float body and the heat hose are heating means. If a large and stable arrangement is made on the horizontal plane in the tank body, the shape and arrangement are not limited to the above-mentioned examples, and various modifications can be made without departing from the scope of the present invention. Of course.

It is the schematic which shows the urea water thawing | decompression apparatus of this invention. FIG. 2 is a schematic view showing the arrangement of the heat hose as seen in the direction of the arrow II-II in FIG. 1. It is the schematic which shows the state which started defrosting the urea water frozen in the urea water thawing | decompression apparatus of this invention. It is the schematic which shows the state which finished thawing | decompressing and sucking the urea water frozen in the urea water thawing | decompression apparatus of this invention. It is the schematic which shows the conventional urea water thawing apparatus. It is the schematic which shows the state in the middle of defrosting the urea water frozen in the conventional urea water defrosting apparatus. It is the schematic which shows the state which finished thawing | decompressing the urea water frozen in the conventional urea water thawing | decompression apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Tank main body 11 Guide rod 12 Float body 13 Suction means 14 Heating means 16 Lower part 18 Heat hose N Urea water (solution)

Claims (5)

  A tank body for storing the solution, a float body floating by the solution in the tank body, a suction means disposed in the float body for sucking the solution, and a solution frozen in the tank body disposed in the float body A urea water thawing device comprising a heating means capable of performing the same.   The urea water thawing device according to claim 1, further comprising a guide rod for guiding a moving direction of the float body.   The urea water thawing device according to claim 1 or 2, wherein the suction means and the heating means are combined into a heat hose.   The urea water thawing device according to any one of claims 1 to 3, wherein a heating means is arranged around the lower part of the float body.   The urea water thawing device according to any one of claims 1 to 4, wherein the heating means is disposed so as to protrude from the outer periphery of the float body.

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