JP5087509B2 - Temperature reduction tower - Google Patents

Description

  The present invention relates to a temperature reducing tower for cooling exhaust gas.

  In general, as a temperature reducing tower for cooling exhaust gas, there is known a temperature reducing tower in which a cooling liquid such as water is sprayed in an received exhaust gas stream and the exhaust gas is cooled by latent heat of evaporation of the cooling liquid.

  However, in such a temperature reducing tower, conventionally, the phenomenon that the flow of the exhaust gas is deviated in one direction due to the influence of the bending of the duct on the exhaust gas introduction side cannot be avoided.

  As a result, high-temperature exhaust gas concentrates and hits one location on the inner wall of the temperature-decreasing tower, causing a local temperature rise in the temperature-decreasing tower, and sprayed droplets Concentrating on one part of the inner wall caused a local temperature drop in the cooling tower, and the sprayed droplets reached the wall before evaporation, causing abnormal adhesion of dust by wetting the wall.

  Recently, in order to prevent such uneven local temperature distribution in the temperature reduction tower and abnormal adhesion of dust that accompanies it, the flow rate distribution is made uniform by preventing the deviation of the flow of the received exhaust gas. Various temperature reduction towers with improved properties have been proposed.

  For example, Patent Document 1 includes a rectifying grid for uniforming the flow of the exhaust gas in the cross-sectional direction and a water spray nozzle for spraying cooling water for cooling the exhaust gas, and the rectifying grid and the water spray nozzle In the meantime, the technology of the temperature control tower characterized by providing the disturbance formation member which forms disturbance in the flow of exhaust gas is disclosed.

Further, in Patent Document 2, in a temperature control tower provided with a spray nozzle for spraying spray water for exhaust gas cooling, an exhaust gas rectifying plate body is arranged in the tower body above the spray nozzle, There is disclosed a technique of a temperature control tower in which air injection pipes are provided annularly along the inner wall surface of the tower main body at a position below the rectifying plate body. In the temperature control tower technique disclosed in Patent Document 2, dust and droplets adhere to the inner wall portion by injecting compressed air downward along the inner wall surface of the tower body to form an air curtain. To prevent that.
JP 2001-347122 A Japanese Patent Laid-Open No. 11-22951

  However, in the technique of the temperature control tower described in the above-mentioned Patent Document 1, since a rectifying grid and a turbulence forming member are arranged in the middle of the exhaust gas flow path, a significant pressure loss occurs in this portion. There is a problem that the power required for transportation increases and the running cost of the equipment increases.

  In the temperature control tower described in Patent Document 1, since the rectification grid and the turbulence forming member are arranged in the middle of the exhaust gas flow path, the dust in the exhaust gas will be removed from the rectification grid and the lapse of time. There was a problem that it may accumulate on the turbulence forming member and hinder the flow of exhaust gas.

  Next, in the technique of the temperature control tower described in Patent Document 2 described above, since the flow straightening plate body of the exhaust gas is disposed above the spray nozzle in the tower body, significant pressure loss is also generated in this portion. As a result, there is a problem that the power required for exhaust gas transportation increases, and that dust in the exhaust gas accumulates on the rectifying plate body over time and may hinder the flow of exhaust gas. It was.

  Moreover, in the temperature control tower technique described in Patent Document 2, the air injection pipe is provided in an annular shape along the inner wall surface of the tower body, so that not only equipment for generating compressed air is required. However, due to the increase in the amount of exhaust gas accompanying the blowing of compressed air, the facilities after the temperature control tower are all increased in size and the cost of the facilities is increased. In addition, there is a problem that the running cost is always increased due to the consumption of compressed air and the accompanying increase in the amount of exhaust gas during operation of the temperature control tower.

  The present invention has been made in view of the above problems, and not only prevents the deviation of the flow of the received exhaust gas and prevents the internal temperature of the temperature reducing tower and the accompanying abnormal adhesion of dust, but also the exhaust gas. To provide a temperature reducing tower with a lower equipment cost that can prevent dust in the exhaust gas from accumulating in the flow path, reduce the pressure loss of the exhaust gas, and reduce the running cost of the equipment. Is an issue.

The present invention for solving the above problems is a temperature reducing tower in which a cooling liquid is sprayed in a flow of received exhaust gas, and the exhaust gas is cooled by latent heat of evaporation of the cooling liquid. A cylindrical straight body portion that is erected in a substantially vertical direction that guides from the bottom to the bottom, and a spray shaft that is directed generally downward in an air flow of exhaust gas guided from the top to the bottom by the straight body portion At least one spray nozzle for spraying the cooling liquid in the direction of, and a generally cylindrical rectifier provided to swirl the exhaust gas received above the spray nozzle around the central axis of the straight body portion; in between the rectifying section and the straight body portion, provided below the rectification section, reduced diameter portion gradually decreasing the flow area of the exhaust gas downward, provided below the reduced diameter portion of this lower Flow path surface of exhaust gas toward Enlarged diameter portion gradually increasing diameter of, and a throttle portion provided between these reduced diameter portion and the enlarged diameter portion, the rectifying section rectifies the exhaust gas along the tangent of the cylindrical side wall of the rectification part An exhaust gas introduction port for receiving the exhaust gas and swirling the exhaust gas around the central axis of the straight body portion, and the spray nozzle is an abbreviation of the flow of the exhaust gas in which the spray shaft is swirled by the straightening portion in the straight body portion. The enlarged diameter portion is provided in the vicinity of the lower portion of the narrowed portion in the enlarged diameter portion so that the side wall of the enlarged diameter portion has an inclination angle of 20 degrees or less with respect to the central axis of the straight body portion. This is a temperature-decreasing tower that expands in diameter.

  According to the present invention, in the rectification unit provided above the spray nozzle, the exhaust gas is received from the exhaust gas inlet of the rectification unit along the tangent to the cylindrical side wall of the rectification unit. The exhaust gas flow velocity distribution due to bending of the exhaust gas introduction side duct or the like can be eliminated.

  As a result, the high temperature exhaust gas does not concentrate and hit one place on the inner wall of the temperature reducing tower, and the local temperature rise of the temperature reducing tower can be prevented. Also, since the sprayed droplets do not concentrate and hit one place on the inner wall of the temperature reducing tower, it is possible to prevent local temperature drop of the temperature reducing tower and abnormal adhesion of dust to the wall surface. become.

  Furthermore, according to the present invention, the reduced diameter portion and the enlarged diameter portion are provided between the rectifying portion and the straight body portion, and the spray nozzle is provided in the enlarged diameter portion. The exhaust gas flow can be formed in a form along the spray shape, and the natural spray shape of the cooling liquid is not greatly disturbed.

  Moreover, according to the present invention, the diameter of the side wall of the enlarged diameter portion is increased at an inclination angle of 20 degrees or less with respect to the central axis of the straight body portion, so that the increase in the cross-sectional area of the enlarged diameter portion is moderate. As a result, the generation of turbulent flow is small, and the cooling liquid spray shape can be made stable without turbulence.

  Furthermore, according to the present invention, in order to realize such rectification of the exhaust gas flow, a rectifying grid, a turbulence forming member, an air curtain device or the like is not arranged in the exhaust gas flow path. There is no increase in shear costs. Moreover, the pressure loss of exhaust gas is not increased, and the running cost of equipment required for exhaust gas transportation is not increased.

  In addition, according to the present invention, since there is no rectifying grid, turbulence forming member, or air curtain device that easily deposits dust in the exhaust gas flow path, dust in the exhaust gas accumulates on these members and devices. It is possible to prevent clogging of the exhaust gas flow.

  Next, the direction of the exhaust gas inlet of the rectifying unit is preferably set in a substantially horizontal direction so that the exhaust gas is received by the rectifying unit from the horizontal direction.

  In this way, since the exhaust gas is received by the rectifying unit from the horizontal direction, more exhaust gas tries to turn horizontally around the central axis of the rectifying unit cylinder. The component becomes smaller, and the flow is reliably swirled around the central axis of the rectification unit, so that the flow rectification is better.

  Moreover, it becomes possible to collect the spray water more effectively at the center of swirling of the exhaust gas that swirls horizontally.

  The exhaust gas inlet has an inlet nozzle side wall portion that is generally along the tangent to the cylindrical side wall of the rectifying unit. The ratio W / Rc between the width W of the exhaust gas inlet port and the inner radius Rc of the rectifying unit is 1. It is preferably 0 or more and 1.5 or less.

  In this way, the introduction nozzle side wall portion of the exhaust gas introduction port is generally along the tangential direction of the cylindrical side wall of the rectification unit, so that less turbulence is generated and the exhaust gas can be smoothly swung along the cylindrical side wall. become able to.

  Further, since the ratio W / Rc between the width W of the exhaust gas introduction port and the inner radius Rc of the rectification unit is 1.0 or more and 1.5 or less, the change in the flow path cross section related to the introduction of the exhaust gas into the rectification unit That is, the difference between the area of the exhaust gas inlet and the horizontal cross-sectional area of the rectification unit is reduced, and the generation of turbulence related to the introduction of exhaust gas into the rectification unit is reduced. As a result, the exhaust gas can be smoothly swung along the cylindrical side wall without being disturbed.

  The vertical component of the exhaust gas flow velocity is preferably 4.5 m / sec or less in the throttle portion between the reduced diameter portion and the enlarged diameter portion.

  In this way, since the vertical component of the exhaust gas flow velocity is 4.5 m / sec at the maximum in the throttle portion provided in the vicinity of the upper part of the spray nozzle, the inertial force of the exhaust gas flow is weakened, and after the enlarged diameter portion This is preferable for rectification of the flow of the gas. Further, since the cross-sectional area is larger than that of the throttle portion around the spray nozzle, the vertical component of the exhaust gas flow velocity is smaller than that of the throttle portion, so that it is possible to avoid greatly disturbing the natural spray shape of the cooling liquid.

  Further, by setting the vertical component of the exhaust gas flow velocity to 4.5 m / sec or less, it is possible to prevent the exhaust gas from being accompanied by the liquid droplets for cooling. Can be a thing.

  Moreover, it is preferable that the said diameter reduction part and the said diameter expansion part are substantially formed in the inverted truncated cone shape and the truncated cone shape, respectively.

  In this way, since the reduced diameter portion and the enlarged diameter portion are each formed in an inverted truncated cone shape and a truncated cone shape, respectively, as a result of any section of these portions being circular, more A stable circular swirl flow with less turbulence can be obtained.

  Moreover, it is preferable that the exhaust gas inlet has a substantially rectangular cross section at the opening.

  In this way, since the cross section of the opening of the exhaust gas inlet is formed in a substantially rectangular shape, the area of the inlet nozzle side wall of the exhaust gas inlet increases, and a large amount of exhaust gas is tangent to the cylindrical side wall of the rectifying unit. You will be able to follow the direction. As a result, a stable swirl flow with less turbulence can be obtained.

  Moreover, it is preferable that the said straight body part is formed in the substantially cylindrical shape.

  In this way, since the straight body portion is formed in a substantially cylindrical shape, any cross section of the straight body portion is circular, so that a stable circular swirl flow with less turbulence can be obtained. Become.

  As explained above, according to the present invention, not only the deviation of the flow of the received exhaust gas is prevented, but the local temperature rise and fall of the cooling tower and the abnormal adhesion of dust to the inner wall are prevented, Providing a temperature-reduction tower with lower equipment costs that can prevent the dust in the exhaust gas from accumulating in the exhaust gas flow path and reduce the exhaust gas pressure loss to reduce the running cost of the equipment There is a remarkable effect that it can be done.

  Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is an explanatory diagram showing a configuration of a gasification and melting system 100 for garbage 21 that employs a temperature reducing tower 10 according to an embodiment of the present invention. Moreover, FIG. 2 is an outline drawing which shows the structure of the temperature decreasing tower 10 which concerns on embodiment of this invention, (a) has shown the top view, (b) has each shown the side view.

  Referring to FIG. 1, a gasification and melting system 100 for garbage 21 shown in the figure includes a temperature reducing tower 10, a gasification furnace 20, a melting furnace 30, a secondary combustion chamber 40, and the like according to an embodiment of the present invention. The heat exchanger or boiler 50 and the exhaust gas treatment facility 60 are provided.

  The gasification furnace 20 is a furnace that receives refuse 21 and thermally decomposes in a state where oxygen is insufficient, and separates it into unburned gas 22 containing carbon and incombustible material 23.

  The melting furnace 30 is a furnace for burning the unburned gas 22 containing carbon generated in the gasification furnace 20 and melting the generated ash to form the slag 31.

  The secondary combustion chamber 40 is a combustion chamber that completely burns the unburned gas 22 containing carbon.

  The heat exchanger or boiler 50 is a heat exchanger that preheats the air sent to the gasification furnace 20, the melting furnace 30, and the secondary combustion chamber 40 with the heat of the exhaust gas G1 from the secondary combustion chamber 40 or the heat of the exhaust gas G1. It is a boiler that generates steam.

  The temperature reduction tower 10 according to the illustrated embodiment of the present invention cools the exhaust gas G2 received from the heat exchanger or the boiler 50, and cools it to the temperature of the exhaust gas G3 that can be supplied to the exhaust gas treatment facility 60. In this configuration, water is sprayed as the cooling liquid L (FIG. 5) in the airflow of the exhaust gas G2, and the exhaust gas G2 is cooled by the latent heat of vaporization of the water.

  As shown in FIG. 2, the temperature reducing tower 10 includes a body portion 11 made of a steel material, and a refractory 12 made of heat-resistant bricks and the like installed on the inner surface of the body portion 11. This refractory 12 is unnecessary when the temperature reducing tower 10 is installed downstream of the boiler and the temperature of the exhaust gas is lowered.

  3A and 3B are detailed views showing the configuration of the body portion 11 of the temperature reducing tower 10, wherein FIG. 3A is a plan view and FIG. 3B is a side view.

  Referring to FIG. 3, the temperature reducing tower 10 includes a cylindrical straight body portion 13, a spray nozzle 14 for spraying the cooling liquid L (FIG. 5), and exhaust gas G <b> 2 on the central shaft 13 d of the straight body portion 13. And a cylindrical rectifying unit 15 provided to swivel around.

  Further, between the straight body portion 13 and the rectifying portion 15, there are provided a diameter-reduced portion 16 that gradually reduces the flow area of the exhaust gas G2, and a diameter-expanded portion 17 that gradually increases and expands the flow area of the exhaust gas G2. ing.

  The straight body portion 13 is a portion formed in a cylindrical shape, is erected substantially in the vertical direction, and is configured to guide the received exhaust gas G2 from above to below. Moreover, in order to discharge | emit the ash content A (FIG. 1) deposited on the bottom part of the exhaust gas derivation | leading-out nozzle 13a and the direct cylinder part 13 for deriving the exhaust gas G2 to this straight body part 13 via the scraper 13b (FIG. 2). The ash discharge port 13c is attached.

  The spray nozzle 14 sprays the cooling liquid L (FIG. 5) substantially downward in the airflow of the exhaust gas G2 guided from above to below by the straight body portion 13. In this embodiment, two or more pairs of the spray nozzles 14 are provided, one pair of which is opposed to the enlarged diameter portion 17.

  The rectifying unit 15 is a part provided to turn the exhaust gas G2 received above the spray nozzle 14 around the central axis 13d of the straight body part. Therefore, the rectifying unit 15 is formed in a cylindrical shape as a whole, and the exhaust gas G2 is received by the rectifying unit 15 along the tangent line of the cylindrical side wall 15a on the cylindrical side wall 15a of the rectifying unit 15. An exhaust gas inlet 15b is provided for turning around the central axis 13d of the straight body portion.

  The exhaust gas inlet 15b has a substantially rectangular cross section in the opening 15c, and the direction of the exhaust gas inlet 15b is set in a substantially horizontal direction so that the rectifier 15 receives the exhaust gas G2 from the horizontal direction. .

  Moreover, this rectification | straightening part 15 is equipped with the rectification | straightening part surplus space 15f above the attachment part 15e of the exhaust gas inlet 15b with respect to the rectification | straightening part 15, and the distance from the upper end of this rectification part surplus space 15f to the lower end of the exhaust gas inlet 15b The ratio Hc / Hic between Hc and the distance Hic from the upper end to the lower end of the exhaust gas inlet 15b is set to 1.0 or more and 1.5 or less. This is because the exhaust gas G2 spreads up and down moderately and evenly in the rectifying unit 15, the downward velocity component of the exhaust gas G2 received from the exhaust gas inlet 15b is reduced, and the flow of the exhaust gas G2 around the spray nozzle 14 is reduced. This is for making the spray axis 14a as a center, and in this embodiment, Hc / Hic is set to 1.5.

  The reduced diameter portion 16 is provided below the rectifying portion 15 and gradually decreases the flow passage area of the exhaust gas G2 toward the lower side, and is formed in an inverted truncated cone shape.

  The enlarged diameter portion 17 is provided below the reduced diameter portion 16, and gradually increases the diameter of the flow path area of the exhaust gas G2 downward, and is formed in a truncated cone shape. And this enlarged diameter part 17 makes the side wall 17a of the enlarged diameter part 17 a straight trunk | drum part in order to make the increase in a flow-path cross-sectional area moderate, and to make the spray shape of the cooling liquid L stable without disturbance. It is set so that the diameter is increased at an inclination angle θ = 20 degrees with respect to the direction of 13 central axes 13d.

  In addition, the vertical component V of the flow rate of the exhaust gas G2 is reduced around the spray nozzle 14 so that the flow rate distribution from the enlarged diameter portion 17 to the straight barrel portion 13 is as small as possible. In order to prevent the spray shape from being disturbed and to prevent the exhaust gas G2 from being accompanied by droplets of the cooling liquid L in the downward direction, in the narrowed portion 18 between the reduced diameter portion 16 and the enlarged diameter portion 17. The vertical direction component V of the exhaust gas G2 flow velocity is set to 4.5 m / sec or less. Here, the vertical direction component V may be calculated from a value measured from a Pitot tube or a hot-wire anemometer at the center of the throttle 18 or from a design maximum flow rate of the exhaust gas G2 and a cross-sectional area of the throttle 18.

  Next, with reference to FIGS. 4-9, the effect | action of the temperature reduction tower 10 which concerns on embodiment of this invention is demonstrated.

  4A and 4B are explanatory views showing the distribution of the high temperature portion of the temperature reducing tower 10 according to the embodiment of the present invention, where FIG. 4A shows a side view and FIG. 4B shows the other side view. Region T represents a temperature region of 270 ° C. or higher and 300 ° C. or lower. FIG. 5 is an explanatory view showing the spray shape of the temperature reducing tower 10, wherein (a) shows a side view and (b) shows another side view.

  With reference to FIGS. 4 to 5, in the temperature reducing tower 10 according to the embodiment of the present invention, as shown in the figure, the straight body portion 13 guides the received exhaust gas G <b> 2 from the top to the bottom and sprays it. The nozzle 14 sprays the cooling liquid L downward in the airflow of the exhaust gas G2.

  At this time, the exhaust gas G2 is received by the rectification unit 15 so that the exhaust gas introduction port 15b of the rectification unit 15 follows the tangent line of the cylindrical side wall 15a (FIG. 3) from the horizontal direction, and the exhaust gas G2 is received by the central shaft 13d of the straight body portion. Rotate around. Further, the rectifying unit surplus space 15f (FIG. 3) moderately spreads the exhaust gas G2 up and down in the rectifying unit 15 so as to reduce the downward velocity component of the exhaust gas G2 received from the exhaust gas inlet 15b. The flow of the exhaust gas G2 around the nozzle 14 is made more uniform around the spray axis 14a.

  Further, the reduced diameter portion 16 gradually decreases the flow area of the exhaust gas G2 downward, and the side wall 17a of the enlarged diameter portion 17 is inclined at an angle θ = 20 degrees or less with respect to the central axis of the straight body portion 13. In order to prevent the natural spray shape of the cooling liquid L from being disturbed, the diameter of the exhaust gas G2 is gradually increased and the flow passage area of the exhaust gas G2 is gradually increased.

  In this way, water is sprayed as the cooling liquid L in the flow of the exhaust gas G2, and the exhaust gas G2 received from the heat exchanger or the boiler 50 is cooled by the latent heat of evaporation of the water, and supplied to the exhaust gas treatment facility 60. The temperature is cooled to a possible temperature. At that time, the high temperature exhaust gas G2 is concentrated on one place on the inner wall portion of the temperature reducing tower 10, or the sprayed droplet is placed on one place on the inner wall portion of the temperature reducing tower 10. I won't focus on it.

  Here, the temperature reducing tower 80 without the rectifying unit 15 and the temperature reducing tower 90 without the rectifying unit surplus space 15f will be described and compared with the temperature reducing tower 10 according to the embodiment of the present invention.

  FIG. 6 is an explanatory view showing the distribution of the high temperature portion of the temperature reducing tower 80 in which the exhaust gas introduction duct 84b is bent and the rectifying unit 15 is not provided, (a) is a side view, and (b) is a side view. The other side views are respectively shown, and a region T represents a temperature region of 270 ° C. or higher and 300 ° C. or lower. Moreover, FIG. 7 is explanatory drawing which shows the spray shape of the temperature reduction tower 80 which does not provide the rectification | straightening part 15, (a) is a side view, (b) has shown the other side view, respectively. .

With reference to FIGS. 6-7, in the temperature reduction tower 80 which does not provide the rectification | straightening part 15, since the exhaust gas introduction duct 84b is bent in the upstream, the drift has arisen inside the exhaust gas introduction duct 84b, When exhaust gas is introduced into the temperature reducing tower 80, the flow velocity distribution inside the temperature reducing tower 80 is biased in one direction due to the influence of this drift. Further, since the exhaust gas flow velocity from the exhaust gas introduction duct 84b is as fast as about 15 m / sec and the inertia of the flow is large, the exhaust gas G2 introduced into the enlarged diameter portion 17 causes flow separation at the enlarged diameter portion, and an uneven flow Is difficult to achieve a uniform flow velocity distribution. As a result, the high-temperature exhaust gas G2 is concentrated and hits one place on the inner wall portion of the temperature reduction tower 80, and a local temperature rise portion 81 of the temperature reduction tower 80 is generated (FIG. 6). Further, the sprayed droplets are extremely close to one place on the inner wall portion of the temperature reducing tower 80, and a local temperature drop portion 82 of the temperature reducing tower 80 is generated. Adhere (FIG. 7).

  FIG. 8 is an explanatory view showing the distribution of the high temperature portion of the temperature reducing tower 90 without the rectifying section surplus space 15f (FIG. 3), where (a) is a side view and (b) is the other side surface. Each figure is shown, and the region T shows a temperature region of 270 ° C. or more and 300 ° C. or less. Moreover, FIG. 9 is explanatory drawing which shows the spray shape of the temperature reduction tower 90 which does not provide the rectification | straightening part surplus space 15f (FIG. 3), (a) is a side view, (b) is the other side surface. Each figure is shown.

  With reference to FIGS. 8 to 9, in the temperature reducing tower 90 without the rectifying unit surplus space 15 f (FIG. 3), the exhaust gas inlet 94 b of the rectifying unit 15 has a cylindrical side wall from the horizontal direction as illustrated. Since the exhaust gas G2 is received by the rectification unit 15 along the tangent line 15a and the exhaust gas G2 is swirled around the central axis 13d (see FIG. 3) of the straight body portion, the flow of the exhaust gas G2 around the spray nozzle 14 is sprayed. It is made more uniform around the axis 14a (FIG. 3). As a result, it is improved that the droplets to be sprayed extremely approach one place on the inner wall portion of the temperature reducing tower 90 (FIG. 9).

  However, since the exhaust gas introduction port 94b is located at the upper end of the rectifying unit 15, the vertically upward flow velocity component is limited inside the rectifying unit 15, and rectification is performed while the exhaust gas G2 is turning the rectifying unit 15. The effect becomes insufficient, and when it is introduced into the enlarged diameter portion 17, an uneven flow occurs. As a result, the natural spray shape of the cooling liquid L is disturbed, and the flow of the exhaust gas G2 is biased in one direction, and the high temperature exhaust gas G2 is biased to the inner wall portion of the temperature reducing tower 10. A non-uniform temperature rise portion 91 of the temperature reducing tower 10 occurs (FIG. 8).

  As described above, according to the temperature reducing tower 10 according to the embodiment of the present invention, in the rectification unit 15 provided above the spray nozzle 14, the exhaust gas inlet 15 b of the rectification unit 15 is connected to the rectification unit 15. Since the exhaust gas G2 is received by the rectification unit 15 along the tangent to the cylindrical side wall 15a, the exhaust gas G2 turns around the central axis of the rectification unit 15 cylinder, and the deviation of the exhaust gas flow velocity distribution due to the bending of the exhaust gas introduction side duct is eliminated. can do.

  As a result, the high temperature exhaust gas G2 is not concentrated and hits one place on the inner wall portion of the temperature reduction tower 10, and the local temperature rise of the temperature reduction tower 10 can be prevented. Further, since the sprayed droplets do not concentrate and hit one place on the inner wall portion of the temperature reducing tower 10, the temperature reaches the wall surface before the temperature drop of the temperature reducing tower 10 decreases or the sprayed droplets evaporate. Also, abnormal adhesion of dust due to wetting the wall surface can be prevented.

  Furthermore, in realizing such rectification of the exhaust gas flow, the initial cost of the equipment is increased because a flow rectifying grid, a turbulence forming member, an air curtain device or the like is not arranged in the flow path of the exhaust gas G2. There is nothing. Moreover, the pressure loss of the exhaust gas G2 is not increased, and the running cost of the equipment required for transporting the exhaust gas G2 is not increased.

  Further, since the flow path of the exhaust gas G2 is not provided with a rectifying grid, a turbulence forming member, or an air curtain device that easily deposits dust, dust in the exhaust gas G2 accumulates on these members and devices, and the flow of the exhaust gas G2 Can prevent clogging.

  Next, according to the temperature reducing tower 10 according to the embodiment of the present invention, since the exhaust gas G2 is received by the rectifying unit 15 from the horizontal direction, more exhaust gas G2 tries to turn horizontally around the spray shaft 14a. As a result, the local downward exhaust gas flow in the vicinity of the exhaust gas inlet 15b is reduced, and the isotropic property of the exhaust gas flow around the spray axis 14a becomes better.

  Moreover, it becomes possible to collect spray water more effectively at the turning center of the exhaust gas G2 turning horizontally.

  According to the temperature reducing tower 10 according to the embodiment of the present invention, the introduction nozzle side wall portion 15d of the exhaust gas introduction port 15b is substantially along the tangential direction of the cylindrical side wall 15a of the rectification unit 15, and therefore separation of the flow occurs. It is difficult to smoothly turn the exhaust gas G2 along the cylindrical side wall 15a.

  Further, since the ratio W / Rc between the width W of the exhaust gas inlet 15b and the inner radius Rc of the rectification unit 15 is 1.0 or more and 1.5 or less, the flow related to the introduction of the exhaust gas G2 into the rectification unit 15 The change in the road cross section, that is, the difference between the area of the exhaust gas inlet 15b and the horizontal sectional area of the rectifying unit 15 is reduced, and the separation of the flow associated with the introduction of the exhaust gas G2 into the rectifying unit 15 is reduced. As a result, the exhaust gas G2 can be smoothly swung along the cylindrical side wall 15a without being disturbed.

  Moreover, according to the temperature-decreasing tower 10 which concerns on embodiment of this invention, the rectification | straightening part surplus space 15f is attachment of the exhaust gas inlet 15b so that Hc / Hic may be 1.0 or more and 1.5 or less. Since the exhaust gas G2 received from the exhaust gas inlet 15b spreads up and down moderately and evenly in the rectifying unit 15, the exhaust gas is introduced compared to the case where there is no rectifying unit surplus space 15f. Most of the exhaust gas G2 received from the port 15b tries to turn horizontally around the central axis of the rectifying unit cylinder. As a result, the flow of the exhaust gas G2 around the spray nozzle 14 becomes more uniform around the spray shaft 14a.

  Further, according to the temperature reducing tower 10 according to the embodiment of the present invention, the reduced diameter portion 16 and the enlarged diameter portion 17 are provided between the rectifying portion 15 and the straight body portion 13, and the spray nozzle 14 is Since it is provided in the lower vicinity of the center of the narrowed portion 18 between the reduced diameter portion 16 and the enlarged diameter portion 17, the exhaust gas flow is formed in a form along the spray shape of the cooling liquid L whose diameter is increased. And the natural spray shape of the cooling liquid L is not greatly disturbed.

  Moreover, according to the temperature reducing tower 10 according to the embodiment of the present invention, the vertical component V of the exhaust gas G2 flow velocity is 4.5 m / sec at most in the throttle portion 18 provided near the upper part of the spray nozzle 14. Therefore, around the spray nozzle 14, the vertical component V of the exhaust gas G2 flow velocity is smaller than this, and it is possible to avoid disturbing the natural spray shape of the cooling liquid L greatly.

  Further, by setting the vertical direction component V of the exhaust gas G2 flow velocity to 4.5 m / sec or less, it is possible to prevent the exhaust gas G2 from being accompanied by the liquid droplets of the cooling liquid L downward. The part 13 can be made shorter.

  Further, according to the temperature reducing tower 10 according to the embodiment of the present invention, the side wall 17a of the diameter-expanded portion 17 is diameter-expanded at an angle of inclination angle θ = 20 degrees or less with respect to the central axis of the straight body portion 13. Therefore, as a result of the gradual increase in the channel cross-sectional area of the enlarged diameter portion 17, the generation of turbulent flow is small, and the spray shape of the cooling liquid L can be stabilized without disturbance.

  In addition, according to the temperature reducing tower 10 according to the embodiment of the present invention, the reduced diameter portion 16 and the enlarged diameter portion 17 are generally formed in an inverted truncated cone shape and a truncated cone shape, respectively. As a result of the circular cross section of any of these portions, a stable circular swirl flow with less turbulence can be obtained.

  Furthermore, according to the temperature reducing tower 10 according to the embodiment of the present invention, since the cross section of the opening 15c of the exhaust gas inlet 15b is formed in a substantially rectangular shape, the inlet nozzle side wall 15d of the exhaust gas inlet 15b The area becomes large, and a lot of exhaust gas G2 can be made to follow the tangential direction of the cylindrical side wall 15a of the rectifying unit 15. As a result, a stable swirl flow with less turbulence can be obtained.

  Further, since the swirling flow of the exhaust gas G2 in the rectifying unit 15 is also uniform between the horizontal cross sections of the rectifying unit 15, a more uniform and stable swirling flow with less turbulent flow can be obtained.

  And according to the temperature-decreasing tower 10 which concerns on embodiment of this invention, since the straight trunk | drum 13 is formed in the substantially cylindrical shape, as a result of all the cross sections of the straight trunk | drum 13 becoming circular, it becomes more disordered. A stable circular swirl flow with less flow can be obtained.

  The above-described embodiment is merely a preferred specific example of the present invention, and the present invention is not limited to the above-described embodiment.

  For example, the application of the temperature reducing tower 10 according to the embodiment of the present invention is not limited to the gasification and melting system 100 of the garbage 21. It can be used in various plants and systems such as steel manufacturing plants, chemical plants, and other industrial plants.

  Moreover, the temperature-decreasing tower 10 is not restricted to the structure provided with the trunk | drum 11 which consists of steel materials, and the refractory 12 installed in the inner surface of the trunk | drum 11, but only the trunk | drum 11 or only a refractory wall by temperature conditions. It is possible to adopt even a configuration consisting of

  The number of spray nozzles 14 that spray the cooling liquid L is not limited to two, and various design changes are possible.

  The cooling liquid L is not necessarily limited to water. Various design changes are possible depending on the plant and system.

  The exhaust gas inlet 15b is not limited to the one in which the section of the opening 15c is formed in a substantially rectangular shape, and the direction of the exhaust gas inlet 15b does not necessarily have to be set in a substantially horizontal direction as shown in the figure. . As long as the exhaust gas G2 is swiveled around the central axis 13d of the straight body portion of the spray nozzle 14, the one in which the opening 15c has a circular cross section is provided on the rectifying portion 15 obliquely. It is.

  The ratio W / Rc of the width W of the introduction nozzle side wall 15d, which is a surface along the tangent to the cylindrical side wall 15a of the rectifying unit 15, and the inner radius Rc of the rectifying unit 15 is not limited to 1.25, but is 1.0. If it is above and below 1.5, various values can be adopted.

  Further, the ratio Hc / Hic between the distance Hc from the upper end of the rectifying portion surplus space 15f to the lower end of the exhaust gas inlet and the distance Hic from the upper end to the lower end of the exhaust gas inlet is not limited to 1.5. If it is 0 or more and 1.5 or less, various values can be adopted.

  The inclination angle of the side wall 17a of the enlarged diameter portion 17 with respect to the central axis of the straight body portion 13 is not necessarily limited to 20 degrees, and various values can be adopted as long as the angle is 20 degrees or less.

  In addition, it goes without saying that various design changes are possible within the scope of the claims of the present invention.

It is explanatory drawing which shows the structure of the gasification-melting system of the waste which employ | adopted the temperature reduction tower which concerns on embodiment of this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is an external view which shows the structure of the temperature decreasing tower which concerns on embodiment of this invention, (a) has shown the top view, (b) has each shown the side view. It is detail drawing which shows the structure of the trunk | drum part of a temperature reduction tower, (a) has shown the top view, (b) has each shown the side view. It is explanatory drawing which shows distribution of the high temperature part of the temperature reduction tower which concerns on embodiment of this invention, (a) shows a side view, (b) shows the other side view, respectively, The area | region T is The temperature range from 270 ° C. to 300 ° C. is shown. It is explanatory drawing which shows the spray shape of a temperature reduction tower, (a) has shown the side view, (b) has each shown the other side view. It is explanatory drawing which shows distribution of the high temperature part of the temperature reduction tower which does not provide a rectification | straightening part, (a) shows a side view, (b) shows the other side view, respectively, and the area | region T is 270 degreeC or more A temperature range of 300 ° C. or lower is shown. It is explanatory drawing which shows the spray shape of the temperature reduction tower which does not provide a rectification | straightening part, (a) has shown the side view, (b) has shown the other side view, respectively. It is explanatory drawing which shows distribution of the high temperature part of the temperature reduction tower which does not provide a rectification | straightening part surplus space, (a) shows a side view, (b) shows the other side view, respectively, The area | region T is 270 A temperature range of not lower than 300 ° C. and lower than 300 ° C. It is explanatory drawing which shows the spray shape of the temperature reduction tower which does not provide the rectification | straightening part surplus space, (a) is a side view, (b) has shown the other side view, respectively.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Temperature reduction tower 13 Straight body part 13d Center axis 14 of straight body part Spray nozzle 14a Spray shaft 15 Rectification part 15a Cylindrical side wall 15b Exhaust gas inlet 15c Exhaust gas inlet 15d Inlet side wall 15e Exhaust gas inlet attachment part 15f Rectifying section surplus space 16 Reduced diameter section 17 Expanded diameter section 17a Side wall 18 of expanded diameter section Restricted section G1 Exhaust gas L Cooling liquid

Claims (7)

A temperature reducing tower that sprays a cooling liquid into an received exhaust gas stream and cools the exhaust gas by latent heat of evaporation of the cooling liquid,
A cylindrical straight body standing in a generally vertical direction for guiding the received exhaust gas from top to bottom;
At least one spray nozzle for spraying the cooling liquid in the direction of the spray axis substantially directed downward in the airflow of the exhaust gas guided from above to below by the straight body portion;
A generally cylindrical rectification unit provided to swirl the exhaust gas received above the spray nozzle around the central axis of the straight body part;
In between the rectifying section and the straight body portion, provided below the rectification section, reduced diameter portion gradually decreasing the flow area of the exhaust gas downward, provided below the reduced diameter portion of this downward A diameter-enlarged portion that gradually increases the diameter of the flow path of the exhaust gas , and a throttle portion provided between the reduced-diameter portion and the enlarged-diameter portion ,
The rectifying unit includes an exhaust gas inlet that receives the exhaust gas into the rectifying unit along the tangent to the cylindrical side wall of the rectifying unit and turns the exhaust gas around the central axis of the straight body part,
The spray nozzle is provided in the vicinity of the lower portion of the throttle portion in the diameter-enlarged portion so that the spray axis is substantially the center of the flow of exhaust gas swirled by the rectifying portion in the straight body portion,
The said diameter-expansion part is a temperature-reduction tower characterized by the diameter-expanding of the side wall of an enlarged-diameter part at an angle of 20 degrees or less with respect to the central axis of a straight body part. 2. The temperature reducing tower according to claim 1, wherein the direction of the exhaust gas inlet of the rectifying unit is set in a substantially horizontal direction so that the exhaust gas is received in the rectifying unit from a horizontal direction. The exhaust gas introduction port has an introduction nozzle side wall portion substantially along the tangent to the cylindrical side wall of the rectification unit,
The temperature reduction according to claim 1 or 2 , wherein the ratio W / Rc between the width W of the exhaust gas inlet and the inner radius Rc of the rectifying unit is 1.0 or more and 1.5 or less. Tower. Reduced according to the vertical component of the exhaust gas flow rate at the throttle portion between the reduced diameter portion and the enlarged diameter portion, any one of claims 1 to 3, characterized in that not more than 4.5 m / sec Warm tower. And the reduced diameter portion, and is the enlarged diameter portion, and the inverted truncated cone shape respectively, reduced according to any one of claims 1 to 4, characterized in that it is generally formed into a truncated conical shape temperature Tower. The temperature reducing tower according to any one of claims 1 to 5 , wherein the exhaust gas inlet has an opening having a substantially rectangular cross section. The temperature reducing tower according to any one of claims 1 to 6 , wherein the straight body portion is formed in a substantially cylindrical shape.

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