JP4522895B2 - Exhaust gas cleaning cooling tower - Google Patents

Description

The present invention relates to an exhaust gas cleaning and cooling tower, and in particular, a non-ferrous smelting furnace provided with an exhaust gas inlet at the upper portion of the tower body and an exhaust gas outlet portion that is cleaned and cooled below the tower body. The present invention relates to an exhaust gas cleaning / cooling tower that performs cleaning and cooling of SO ₂ gas and the like discharged in the above.

For example, when producing sulfuric acid from SO ₂ gas discharged by non-ferrous smelting, generally dust in the gas is removed with a dry electrostatic precipitator, and then a large amount of cleaning / cooling water is circulated in the exhaust gas cleaning cooling tower. Then, impurities such as dust, SO ₃ , F, and Cl in the gas are removed and cooled.

  By this operation, impurities in the gas are absorbed by the cleaning / cooling water, and the cleaning / cooling water becomes dilute sulfuric acid containing impurities.

  In order to protect the exhaust gas cleaning and cooling tower from the above-mentioned dilute sulfuric acid and F and Cl in the gas, the inner wall of the tower is usually made of an acid-resistant material using carbon brick as a brick material and Eifuran mortar as a joint material. ing.

  On the other hand, since such an acid-resistant material is easily attacked by F and Cl in the gas, for example, in the exhaust gas cleaning cooling tower described in Patent Document 1, cleaning and cleaning are performed on a soot provided around the inner surface of the tower body. By injecting cooling water and flushing the cooling water uniformly from the fence to the inner wall of the tower, the inner wall is constantly cooled and wetted to prevent deterioration of the brick structure due to repeated high temperature drying and low temperature wetting. .

  In the structure described in Patent Document 1, when dust adheres to the surface overflowing from the soot to the inner wall of the tower, it becomes difficult to uniformly wet the inner wall of the tower because the washing / cooling water does not flow in this portion. .

  In addition, when the soot inside the tower is damaged, it cannot be repaired during operation, and it becomes difficult to uniformly wet the inner wall of the tower, leading to early deterioration of the inner wall of the tower.

  In addition, since the exhaust gas cleaning / cooling tower performs impurity removal and cooling with cleaning / cooling water as described above, there is a gas-liquid interface inside the tower above the supply unit for supplying cleaning / cooling water. Exists.

  In general, acid-resistant porcelain bricks are used as brick materials and heat-resistant and acid-resistant materials such as acid mortar are used as jointing materials at high temperatures at the entrance of the tower. It has the problem that it is easy to be done.

  On the other hand, under the wet conditions inside the tower, as described above, acid-resistant materials such as the above-mentioned carbon bricks and eye furan mortar are used, but there is a problem that they are vulnerable to high temperatures.

Therefore, it is necessary to accurately grasp the gas-liquid interface and use materials that meet the conditions.However, since the gas-liquid interface fluctuates due to fluctuations in the exhaust gas amount and changes in the spray dispersion state, it is necessary to select materials. It is difficult and the deterioration of this part is particularly severe.
Japanese Patent Laid-Open No. 10-80618

  An object of the present invention is to provide an exhaust gas cleaning / cooling tower that can suppress deterioration of the inner wall of the tower, greatly extend the life of the tower body, and can be easily attached / detached to the cleaning / cooling water spray device. is there.

The above object is achieved by the exhaust gas cleaning cooling tower according to the present invention. In summary, the present invention comprises a non-ferrous smelting exhaust gas inlet at a temperature of 200 to 400 ° C. at the top of the tower body, and a cleaned and cooled exhaust gas outlet at the bottom of the tower body. In the exhaust gas cleaning cooling tower in iron smelting,
Adjacent to the exhaust gas inlet portion, provided a swirl flow forming spray device provided with a plurality of injection nozzles in the circumferential direction of the inner wall of the tower body,
The ejection nozzle of the swirl flow forming spray apparatus, the injection flow from one of the adjacent injection nozzle, and injected to reach the injection port of the injection nozzle located downstream of the jet, cleaning by the ejection nozzle -By injection of cooling water, an injection flow composed of an annular cleaning / cooling water swirling along the circumferential direction of the inner wall is formed,
The jet flow is caused to flow downward along the inner wall surface of the tower body to form a spiral wetting wall,
The upper inner wall surface of the injection nozzle is located inward from the injection port of the injection nozzle to the center of the tower, forming a step between the lower inner wall surface, and cleaning from the injection nozzle -Preventing the jet of cooling water from scattering to the inner wall surface above the jet nozzle,
A gas for injecting cleaning / cooling water into the exhaust gas, comprising a plurality of injection nozzles positioned below the injection nozzle of the swirl flow forming spray device and arranged in the circumferential direction of the inner wall of the tower body Equipped with a washing and cooling spray device,
This is an exhaust gas cleaning cooling tower in non-ferrous smelting.

According to an embodiment of the present invention, the spray nozzle of the swirl flow forming spray device is detachably mounted in a nozzle mounting hole of the tower body.

  According to another embodiment of the present invention, the spray nozzle of the swirl flow forming spray device is made of resin.

According to the present invention,
(1) Although the life of the gas-liquid interface brick at the entrance of the exhaust gas cleaning cooling tower in conventional non-ferrous smelting was 2 to 3 years, it can achieve a life of 3 times or more.
(2) Since the spray device can be repaired from the outside, it is not necessary to stop the operation for the device repair, and the operation efficiency can be improved.
(3) Although the temperature of the cleaning / cooling water used in the swirl flow forming spray device is 30 to 70 ° C., the spray nozzle in the swirl flow forming spray device is installed from the outside of the tower through the tower, and is injected from the outside. The temperature of the nozzle can be measured, and the cleaning / cooling water injection status can be easily detected from the measurement result.
(4) The cleaning / cooling water discharged from each spray nozzle is always applied to the spray nozzle adjacent to the cleaning / cooling water discharge side, and it is possible to prevent the spray nozzle from being melted at a high temperature. For this purpose, a resin injection nozzle can be used.

  Hereinafter, the exhaust gas cleaning cooling tower according to the present invention will be described in more detail with reference to the drawings.

Example 1
FIG. 1 shows a schematic configuration of an embodiment of an exhaust gas cleaning cooling tower according to the present invention.

  In this embodiment, the exhaust gas cleaning / cooling tower 1 includes a tower main body 2 having a substantially cylindrical shape, and the tower main body 2 is installed in a substantially vertical state by a base 3. A cylindrical exhaust gas inlet part 4 is provided at the upper part of the tower body 2, and a cylindrical exhaust gas outlet part 6 extending laterally from the tower body 2 is provided adjacent to the lower bottom wall 5 of the tower body 2. Yes.

  The wetted part of the tower body central part 7 between the upper exhaust gas inlet part 4 and the lower exhaust gas outlet part 6 of the tower body 2 is configured using an acid resistant material such as carbon brick.

  In this embodiment, the inlet section 4 of the tower body 2 has a boundary area 4A connected to the tower body center section 7 and an inlet area 4B extending from the boundary flow area 4A to the gas inlet 4C at the top of the tower. Although the boundary region 4A has an iron wall 8 on the outside, the inner wall 12 is manufactured using a carbon brick having high acid resistance as a brick material.

  Further, the inner diameter of the inner wall 12 of the inlet portion is made smaller than the inner diameter of the inner wall 10 of the central portion 7 of the tower body, and accordingly, the lower end portion of the inner wall of the boundary region 4A of the inlet portion 4 of the tower body and the inner wall 10 of the central portion 7 of the tower body. An annular step 13 is formed between the upper end. The operation of the step 13 will be described later.

  Further, the outer iron wall 8 in the inlet region 4B of the tower main body upper inlet portion 4 is configured to be inclined from the boundary region 4A to the top opening 4C. The inner wall 14 of the entrance region 4B is formed from the boundary region 4A to the top opening 4C with the same inner diameter as the inner wall 12 of the boundary region 4A, and is manufactured using an acid-resistant ceramic brick or the like as a brick material.

  Moreover, in the present Example, the tower main body lower bottom part 5 and the waste gas outlet part 6 are comprised using the outer iron wall 8 and the carbon brick as a brick material of an inner wall.

  In the above embodiment, in particular, the tower body inner walls 10, 12 and the like use carbon brick as a brick material, and the tower body inner wall 14 uses acid-resistant porcelain brick as a brick material. The inner wall 16 and the like have been described as using carbon brick as a brick material, but the material of the inner wall is not limited to this. For example, franc bricks can be used instead of carbon bricks, and other various bricks can be used.

  Next, with reference to FIG.2 and FIG.3, the swirl | vortex flow formation spray apparatus 100 formed in the tower main body upper inlet part 4 which makes the characteristic of a present Example is demonstrated.

  In this embodiment, the swirl flow forming spray device 100 is provided below the boundary region 4A of the tower main body upper inlet portion 4, that is, in the upper end region 7A of the tower main body central portion 7.

  As can be understood with reference also to FIG. 2, in the upper end region 7 </ b> A of the tower body central portion 7, eight in this embodiment, eight injection nozzles 101 of the swirl flow forming spray device 100. Nozzle mounting hole 20 is formed for mounting. The nozzle mounting hole 20 is formed at a predetermined angle (α) with respect to the central portion O1 of the tower main body 2 and, in the present embodiment, inclined by 45 °. Therefore, in the present embodiment, the inclination angle (β) between the mounting holes 20 adjacent to each other is also set to 45 °.

  Further, as shown in FIG. 3, the nozzles 101 of the swirl flow forming spray device 100 are detachably mounted in the nozzle mounting holes 20. As shown in FIG. 5, cleaning / cooling water is supplied to the injection nozzle 101 at a predetermined pressure and flow rate via a flow rate adjustment valve 110 and a communication pipe 111. As a result, as shown in FIG. 3, the jet flow 103 from one of the adjacent jet nozzles 101 is jetted so as to reach the vicinity of the jet port 102 of the jet nozzle 20 located on the downstream side of the jet flow 103. As the cleaning / cooling water, the cleaning / cooling water used in the cleaning tower can be partially circulated and used.

  With such an arrangement configuration of the injection nozzles 20, 20, as shown in FIG. 2, the injection flow 103 from each injection nozzle 20 becomes a swirl flow, inside the tower body 2, on the inner periphery of the inner wall. A swirl jet layer 104 having an annular shape is formed. As shown in FIG. 5, the annular swirl jet layer 104 flows downward along the inner wall of the tower body due to gravity, and a spiral wetting wall 105 composed of the swirl jet layer 104 is formed in the tower body. Form. The thickness (t) of the wet wall can be 1 to 5 mm.

  According to the present embodiment having the above-described configuration, in particular, the spray nozzle 101 of the swirling flow forming spray device 100 is configured to be mountable in the mounting hole 20 formed through the tower main body 2. The temperature of the injection nozzle can be measured, and the state of injection in the tower can be easily detected from the temperature.

  Further, when the injection nozzle 101 becomes clogged, as shown in FIG. 5, the cleaning / cooling water flow rate adjustment valve 110 is closed and the communication pipe 111 is removed, so that the injection nozzle 100 is removed / replaced. Is easily possible.

  As described above, the cleaning / cooling water from the swirl flow forming spray device 100 is constantly injected to the nozzle port 102 of the adjacent injection nozzle 20, so that the high-temperature gas does not directly contact the injection nozzle 20. It has become. Accordingly, it is possible to prevent the spray nozzle 20 from being melted at a high temperature. Therefore, the injection nozzle 20 can be made of resin, and cost reduction can be achieved. As the resin, vinyl chloride, fluororesin, FRP (fiber reinforced plastic), or the like can be used.

  Further, as described above, the spray nozzle 101 of the swirl flow forming spray device 100 is provided below the boundary region 4A of the tower main body upper inlet portion 4, that is, in the upper end region 7A of the tower main body central portion 7. As described above, the inner wall 4 </ b> A of the boundary region 4 </ b> A of the tower main body upper inlet portion 4 is covered with a step 13 at the upper portion of the injection nozzle 102 of the injection nozzle 101. Accordingly, a constant gas-liquid boundary surface is formed by the inner wall 4A that forms the step 13, and the cleaning / cooling water from the spray nozzle 101 of the swirl flow forming spray device 100 enters the boundary region 4A of the upper inlet portion 4 in the high temperature zone. Prevent splashing. The carbon brick in the boundary region 4A is cooled by the swirl flow forming spray water to prevent the carbon brick from being melted.

  An injection nozzle 201 of the gas cleaning / cooling spray device 200 is disposed adjacent to and below the injection nozzle 101 of the swirl flow forming spray device 100. Therefore, a mounting hole 30 for mounting the gas cleaning / cooling injection nozzle 201 is formed in the tower body 2.

  Moreover, as shown in FIG. 5, the spray nozzle 201 of the gas cleaning / cooling spray device 200 is detachably mounted in each nozzle mounting hole 30. Cleaning / cooling water is supplied to the injection nozzle 201 at a predetermined pressure and flow rate via the flow rate adjustment valve 210 and the communication pipe 211.

  In the present embodiment, with the above-described configuration, the cleaning / cooling water from the gas cleaning / cooling injection nozzle 201 is sprayed toward the center of the tower body 2 and inclined horizontally or slightly downward. The Therefore, the exhaust gas flowing into the tower body 2 is washed and cooled by the jet flow from the gas washing / cooling jet nozzle 201.

  Thus, in this embodiment, in addition to the injection nozzle 101 of the swirl flow forming spray device 100, the injection nozzle 201 of the normal gas cleaning cooling spray device 200 is arranged below the injection nozzle 101. With this configuration, further effects can be obtained with respect to cleaning and cooling.

  Next, the operation of the exhaust gas cleaning / cooling tower 1 having the above-described configuration will be described more specifically with reference to FIG.

The exhaust gas to be treated in the exhaust gas cleaning / cooling tower 1 of the present embodiment is, for example, an exhaust gas having an SO ₂ concentration of 1 to 50 vol% and an exhaust gas temperature of 200 to 400 ° C. The exhaust gas of this composition and temperature is generated in the exhaust gas of non-ferrous smelting. For example, the exhaust gas of a copper converter or the exhaust gas of a flash smelting furnace in copper dry smelting.

These gases are further rich in impurities such as dust, F, and Cl. For example, the dust is 0.1 to 2.0 g / Nm ³ , F is 0.01 to 1.0 vol%, Cl is 0.01 to 1.0 vol%, and SO ₃ is 0.03 to 1.5 vol. % Is included.

Usually, these exhaust gas amounts are 500-3500 Nm < ³ > / min.

  These gases are cleaned and cooled in the exhaust gas cleaning cooling tower 1 of this embodiment before being sent to the next process.

  In the present embodiment, at the time of cleaning and cooling, cleaning / cooling water, which is made into a cleaning tower circulating liquid or the like by the gas cleaning / cooling spray device 100, is sprayed by the spray nozzle 101 with respect to the exhaust gas.

  Furthermore, according to the present embodiment, the swirl flow forming spray device 100 is located at the upper end 7A (FIG. 1) of the central part of the exhaust gas cleaning cooling tower 1 and adjacent to the lower boundary region 4A (FIG. 1) of the exhaust gas inlet. Thus, a spiral wetting wall 105 (FIG. 5) is formed on the inner wall 10 of the exhaust gas cleaning / cooling tower 1.

  Thereby, wear of an inner wall brick can be prevented beforehand.

The water temperature of the cleaning / cooling water supplied to the spray nozzle 101 of the swirl flow forming spray device 100 is 30 to 70 ° C. The amount of water supplied to the injection nozzle 101 is 1 to 5 m ³ / hour per nozzle, and the water pressure of the nozzle is 0.1 to 0.5 Mpa per injection nozzle.

  In the present embodiment, as described above, in addition to the swirl flow forming spray device 100, the normal gas cleaning cooling spray device 200 is disposed below the swirl flow forming spray device 100.

In this case, the amount of cleaning / cooling water to the injection nozzle 201 in the gas cleaning cooling spray device 200 is 10 to 50 m ³ / hour per nozzle, and the nozzle water pressure is 0.1 to 0 per injection nozzle. .5 Mpa.

  Next, mainly with reference to FIG. 5 and FIG. 6, the effect of the exhaust gas cleaning cooling tower of the present embodiment will be described based on experimental examples.

Experimental Example In this experimental example, the exhaust gas cleaning cooling tower 1 having the configuration described in the above example was used, and the copper flash smelting furnace / copper converter exhaust gas was cleaned and cooled. The amount of exhaust gas was 500-3300 Nm ³ / min.

Further, the composition of the exhaust gas, SO ₂ was 0~35Vol%. The exhaust gas temperature was 200 to 350 ° C., the dust was about 0.2 g / Nm ³ , F was about 0.1 Vol%, and Cl was about 0.1 Vol%.

In the exhaust gas cleaning cooling tower 1, the spray nozzle 101 of the swirl flow forming spray device 100 has an elliptical shape with a diameter of 15 × 10 mm, the amount of water is 2 m ³ / hour / main, and the spray pressure is 0.2 Mpa. .

  The material of the injection nozzle 101 was a fluororesin. The brick material of the inner wall 10 was carbon brick, and the joint material was Eiflan mortar.

  With the above-described configuration, a wetting wall 105 is spirally formed on the inner wall 10 of the cleaning cooling tower by the swirl jet flow 104 from the spray nozzle 101 of the swirl flow forming spray device 100. The thickness (t) of the wet wall 105 was 1 to 5 mm.

  In addition, the gas cleaning cooling spray device 200 is provided below the swirl flow forming spray device 100.

The spray nozzle 201 of the gas cleaning / cooling spray apparatus 200 has a diameter of 20 mm, a water amount of 20 m ³ / hour, and a spray pressure of about 0.2 MPa. The injection nozzle 201 was made of a fluororesin.

  As a result, the exhaust gas cleaning / cooling tower 1 has an excellent effect that cannot be obtained by the conventional cleaning tower shown as a comparative example in FIG. I was able to get it.

  FIG. 6 shows a conventional exhaust gas cleaning cooling tower 1A as a comparative example. This conventional exhaust gas cleaning cooling tower 1A does not include the swirl flow forming spray device 100 in this embodiment, and a spray device 200A corresponding to the gas cleaning cooling spray device 200 of this embodiment is provided in the tower body 2. It is installed in two upper and lower stages.

  When the exhaust gas cleaning cooling tower 1A of the comparative example was carried out under the conditions of the above experimental example, the tower body inner wall bricks were eroded severely due to scattering of the jet flow from the injection nozzle 201 and unevenness of the wet wall. As shown in the conventional method, a favorable result was not obtained.

It is a schematic block diagram of one Example of the exhaust gas washing cooling tower which concerns on this invention. It is sectional drawing taken on line II-II of FIG. 1 for demonstrating arrangement | positioning of a swirl | vortex flow formation spray apparatus. It is a figure for demonstrating the washing | cleaning and cooling water dispersion | distribution state of the injection nozzle in a swirl flow formation spray apparatus. It is sectional drawing taken on line IV-IV of FIG. 1 for demonstrating arrangement | positioning of the spray apparatus for gas washing cooling. It is a schematic block diagram of the exhaust gas washing cooling tower for demonstrating the action | operation of a swirl | flow-form formation spray apparatus and the spray apparatus for gas washing cooling. It is a schematic block diagram which shows the conventional gas washing cooling tower.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Gas washing cooling tower 2 Tower main body 4 Tower main body inlet part 4A Boundary region 6 Tower main body outlet part 7 Tower main body central part 7A Tower main body center upper end 10 Tower main body central part inner wall 12 Boundary area inner wall 13 Washing liquid splash prevention inner wall level | step difference 20 , 30 Spray nozzle mounting hole 100 Swirling flow forming spray device 101 Spray nozzle 200 Spraying device for gas cleaning and cooling 201 Spray nozzle 104 Swirling spray layer 105 Wetting wall

Claims (3)

In an exhaust gas cleaning cooling tower in non-ferrous smelting, provided with an inlet portion of non-ferrous smelting exhaust gas having a temperature of 200 to 400 ° C. at the top of the tower body, and having an outlet portion of exhaust gas cleaned and cooled below the tower body ,
Adjacent to the exhaust gas inlet portion, provided a swirl flow forming spray device provided with a plurality of injection nozzles in the circumferential direction of the inner wall of the tower body,
The ejection nozzle of the swirl flow forming spray apparatus, the injection flow from one of the adjacent injection nozzle, and injected to reach the injection port of the injection nozzle located downstream of the jet, cleaning by the ejection nozzle -By injection of cooling water, an injection flow composed of an annular cleaning / cooling water swirling along the circumferential direction of the inner wall is formed,
The jet flow is caused to flow downward along the inner wall surface of the tower body to form a spiral wetting wall,
The upper inner wall surface of the injection nozzle is located inward from the injection port of the injection nozzle toward the center of the tower, and forms a step between the lower inner wall surface and cleaning from the injection nozzle. Preventing the jet of cooling water from scattering to the inner wall surface above the jet nozzle;
A gas for injecting cleaning / cooling water into the exhaust gas, comprising a plurality of injection nozzles positioned below the injection nozzle of the swirl flow forming spray device and arranged in the circumferential direction of the inner wall of the tower body Equipped with a washing and cooling spray device,
An exhaust gas cleaning cooling tower in non-ferrous smelting.   The exhaust gas cleaning cooling tower according to claim 1, wherein the spray nozzle of the swirl flow forming spray device is detachably mounted in a nozzle mounting hole of the tower main body.   The exhaust gas cleaning cooling tower according to claim 1 or 2, wherein the spray nozzle of the swirl flow forming spray device is made of resin.

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