JP2009114233A - Liquid phase oxidation wet type desulphurization apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid phase oxidation wet type desulphurization apparatus not requiring installation of new facilities or a plurality of pumps and realizing an excellent deaeration function. <P>SOLUTION: The liquid phase oxidation wet desulphurization apparatus 10 includes an absorption tower 102 for absorbing and removing a material to be oxidized in coke-oven gas with an absorbent solution, and an oxidization tower 104 for oxidizing the matter to be oxidized included in the absorbent solution supplied from the absorption tower and regenerating the absorbent solution to discharge it. In the oxidation tower 104, at least one weir plate 136, which is raised from the bottom part of the oxidation tower 104 to let air bubbles included in the absorbent solution float, and at least one partition plate 138, which is installed with its bottom end separated from the bottom part for letting air bubbles included in the absorbent solution float, are arranged alternately on a flow line, through which the absorbent solution is supplied and discharged, of the absorbent solution. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a liquid phase oxidation wet desulfurization apparatus.

  The desulfurization equipment used to desulfurize coke oven gas produced when carbonizing coal to produce coke mainly consists of an absorption tower that absorbs and removes oxides in the coke oven gas with an absorption liquid, and an absorption tower Two towers called an oxidation tower that oxidizes the oxide by blowing air into the absorbing solution that has absorbed the oxide delivered from the tower are provided. In order to extract and circulate the absorption liquid from the oxidation tower, a circulation pump directly connected to the oxidation tower is used, but if air bubbles blown for oxidation of the oxide remain in the absorption liquid, Bubbles may be caught in the circulation pump and cavitation of the circulation pump may occur. In order to prevent cavitation of the circulation pump, it is important to degas bubbles generated in the oxidation tower.

  Regarding the deaeration treatment of bubbles in the oxidation tower, a circulation pump is not directly connected to the oxidation tower, but a deaeration tank exclusively for deaeration is provided between the oxidation tower and the circulation pump, and the bubbles to the circulation pump are There have been proposed a method for preventing entrainment (for example, see Patent Document 1), a method for improving the deaeration performance by changing the structure in the oxidation tower (for example, see Patent Document 2), and the like.

JP-A-3-42011 Japanese Patent Publication No.58-49590

  However, the method described in Patent Document 1 has a problem that a space for installing a deaeration tank is newly required, and the method described in Patent Document 2 requires a plurality of pumps. However, it was not economical.

  Therefore, the present invention has been made in view of such a problem, and the purpose thereof is a new one that does not require installation of new equipment and a plurality of pumps, and can realize an excellent deaeration function. Another object of the present invention is to provide an improved liquid phase oxidation wet desulfurization apparatus.

  As a result of intensive studies to solve the above problems, the inventors of the present application realize an excellent deaeration function by installing a member in the oxidation tower for promoting bubble formation and facilitating floating. I realized that it was possible.

  The present invention has been completed based on such findings, and the gist of the present invention is as follows.

(1) An absorption tower that absorbs and removes the oxide in the coke oven gas with an absorption liquid, and the oxide contained in the absorption liquid supplied from the absorption tower is oxidized to regenerate the absorption liquid. A liquid phase oxidation wet desulfurization apparatus comprising a discharge oxidation tower, wherein the oxidation tower is erected from a bottom portion of the oxidation tower on a flow path of the absorption liquid from supply of the absorption liquid to discharge. At least one dam plate that floats the bubbles contained in the absorption liquid and a partition plate that is provided so that the lower end is separated from the bottom and floats the bubbles contained in the absorption liquid are provided alternately. A liquid-phase oxidative wet desulfurization apparatus.
(2) The inside of the oxidation tower is lower than the oxidation tower and has an opening at the upper end, and is located inside the inner tower to which the absorbing liquid is supplied from the absorption tower, and outside the inner tower. And an outer tower into which the absorbing liquid overflowing from the opening flows, and the weir plate and the partition plate on the flow path of the absorbing liquid in the outer tower The liquid phase oxidation wet desulfurization apparatus according to (1), wherein the liquid phase oxidation wet desulfurization apparatus is provided.
(3) The liquid phase oxidation wet desulfurization apparatus according to (2), wherein the absorption liquid overflowing from the opening flows into the outer tower with a drop.
(4) The liquid phase oxidation wet desulfurization apparatus according to any one of (1) to (3), wherein the barrier plate and the partition plate are arranged radially from a central axis of the oxidation tower.
(5) The liquid phase oxidation wet according to any one of (1) to (4), wherein the oxidation tower further includes a gas-liquid mixing device that ejects an oxidizing air that oxidizes the absorption liquid. Desulfurization equipment.
(6) The liquid according to any one of (1) to (5), wherein the oxidation tower further includes a circulation pump for sucking the regenerated absorption liquid and circulating it to the absorption tower. Phase oxidation wet desulfurization equipment.
(7) The liquid phase oxidation wet desulfurization apparatus according to any one of (1) to (6), wherein the absorption tower and the oxidation tower are integrally formed.
(8) The liquid phase oxidation wet desulfurization apparatus according to any one of (1) to (7), wherein an upper end of the barrier plate is located above a lower end of the partition plate.
(9) The liquid phase oxidation wet desulfurization apparatus according to any one of (1) to (7), wherein an upper end of the dam plate is located below a lower end of the partition plate.
(10) The liquid phase oxidation wet desulfurization apparatus according to any one of (1) to (7), wherein an upper end of the dam plate is positioned at the same height as a lower end of the partition plate.

  According to the present invention, it is not necessary to install new equipment or a plurality of pumps, and an excellent deaeration function can be realized.

  Exemplary embodiments of the present invention will be described below in detail with reference to the accompanying drawings. In addition, in this specification and drawing, about the component which has the substantially same function structure, duplication description is abbreviate | omitted by attaching | subjecting the same code | symbol.

(First embodiment)
Hereinafter, the liquid phase oxidation wet desulfurization apparatus 10 according to the first embodiment of the present invention will be described in detail with reference to FIGS.

(Configuration of liquid phase oxidation wet desulfurization apparatus 10)
FIG. 1 is an explanatory diagram for explaining a liquid phase oxidation wet desulfurization apparatus according to a first embodiment of the present invention. As shown in FIG. 1, the liquid phase oxidation wet desulfurization apparatus 10 according to this embodiment includes, for example, an absorption tower 102, an oxidation tower 104, and a communication pipe 106 that communicates the absorption tower 102 and the oxidation tower 104. Prepare.

  The absorption tower 102 absorbs and removes the oxide in the raw coke oven gas 108, which is the gas to be treated, with an absorption liquid (post-oxidation absorption liquid 112). The absorption liquid (non-oxidized absorption liquid 110) that has absorbed the oxide naturally flows into the oxidation tower 104 described later from the lower part of the absorption tower 102. Here, the oxide in the raw coke oven gas 108 is, for example, hydrogen sulfide or hydrogen cyanide, and the absorbing solution is in contact with the oxide such as hydrogen sulfide or hydrogen cyanide, and these oxides are removed. Absorb. Moreover, said unoxidized absorption liquid means the absorption liquid in the state in which the oxide absorbed by said absorption liquid has not yet been oxidized.

  The absorption tower 102 is provided with a spray nozzle for absorbing liquid at the top of the tower, and at the bottom of the tower is formed an absorption tower lower liquid reservoir in which the absorption liquid sprayed from the spray nozzle and absorbing the oxide is temporarily stored. Has been. In addition, a contact portion is provided between the spray nozzle and the absorption tower lower liquid reservoir so as to be filled with a suitable filler and to counter-contact with the raw material coke oven gas 108 introduced from the gas inlet. . Furthermore, a discharge port for discharging the purified coke oven gas 126 generated by removing the oxide from the raw material coke oven gas 108 is installed at the top of the absorption tower 102.

  The oxidation tower 104 blows air into an absorption liquid (non-oxidation absorption liquid 110) that has absorbed the oxide supplied from the absorption tower 102, and oxidizes the oxidation target such as hydrogen sulfide or hydrogen cyanide to thereby absorb the post-oxidation absorption liquid. The absorbent is regenerated as 112, and bubbles due to unreacted air are removed from the absorbent. A gas-liquid mixing device 114 including a plurality of air blowing nozzles and the like is provided at the lower portion of the oxidation tower 104. The gas-liquid mixing device 114 provided in the oxidation tower 104 according to the present embodiment is not particularly defined. For example, it is possible to use the gas-liquid mixing device described in JP-A No. 62-192490. Is possible. In FIG. 1, only one gas-liquid mixing device 114 is illustrated, but the gas-liquid mixing device 114 may be provided in the oxidation tower 104 without being limited to the illustrated example. Here, the post-oxidation absorption liquid refers to an absorption liquid in a state where the oxide to be absorbed in the absorption liquid is oxidized by the air blown from the gas-liquid mixing device 114.

  Further, the oxidation tower 104 is provided with a circulation pump 120 for circulating the absorption liquid in which the oxide is oxidized. The circulation pump 120 sucks the oxidized absorption liquid 112 from which bubbles have been removed from the oxidation tower 104, circulates it to the spray nozzle at the top of the absorption tower 102, and gas-liquid mixes a part of the absorption liquid 112 after oxidation. Is supplied to the gas-liquid mixing device 114 as the absorption liquid 122 for use.

  In the gas-liquid mixing device 114, the oxidizing air 118 supplied from the blower 116 and the gas-liquid mixing absorbing liquid 122 supplied from the circulation pump 120 are mixed and ejected into the oxidation tower 104. The ejected oxidation air 118 oxidizes the oxide in the unoxidized absorption liquid 110 naturally flowing from the absorption tower 102 to make the unoxidized absorption liquid 110 into an after-oxidation absorption liquid 112.

  Near the bottom of the oxidation tower 104, there are provided a weir plate 136 and a partition plate 138 for removing bubbles generated by the oxidizing air 118 ejected from the gas-liquid mixing device 114. These barrier plate 136 and partition plate 138 will be described in detail below.

  The bubbles separated from the absorption liquid 112 after oxidation become the oxidation tower waste gas 124, are discharged from the top of the oxidation tower 104, and are sent to waste gas treatment.

  The communication pipe 106 is a pipe that connects the tower bottom of the absorption tower 102 and the tower bottom of the oxidation tower 104, and an unoxidized absorption liquid 110 that has absorbed an oxide such as hydrogen sulfide in the absorption tower 102 is formed by the oxidation tower 104. It becomes a flow path for natural inflow into.

  Subsequently, the weir plate 136 and the partition plate 138 provided in the oxidation tower 104 according to the present embodiment will be described in detail with reference to FIGS. 2 and 3. In addition, although FIG. 2 demonstrates the case where the oxidation tower 104 which concerns on this embodiment has a substantially cylindrical shape, the shape of the oxidation tower 104 which concerns on this embodiment is not necessarily limited to a substantially cylindrical shape. .

  When the oxidation reaction of the oxide absorbed by the absorption liquid is performed in the oxidation tower 104, the bubbles are removed by the unreacted air (oxygen in the air) regardless of the shape of the gas-liquid mixing device 114. Is inevitable. The lower the water depth of the oxidation tower 104, the lower the flying height at which bubbles must rise. Therefore, theoretically, if the oxidation reaction is carried out in an oxidation tower having an infinite surface area, degassing (air bubbles Removal) is also possible. However, since an oxidation tower having an infinite surface area cannot be installed, it is necessary to take some measures for the deaeration treatment.

  Since the flow direction of the absorption liquid and the flow direction of the bubbles are the same, care must be taken when processing the absorption liquid continuously. That is, if treated intermittently, it is possible to naturally deaerate by ensuring a suitable standing time, but like the liquid phase oxidation wet desulfurization apparatus 10 according to the present embodiment, When the absorbent must be processed continuously and there is a physically acceptable installation area including economy, it is necessary to consider a structure that takes into account the degassing mechanism. Therefore, in the oxidation tower according to the present embodiment, a dam plate 136 and a partition plate 138 as described below are provided to degas the absorbent.

  FIG. 2 is an explanatory diagram when the tower bottom of the oxidation tower 104 according to the present embodiment is viewed from above, and is an explanatory diagram for explaining the weir plate 136 and the partition plate 138 according to the present embodiment. FIG. 3 is an explanatory view showing the flow path extending from the absorbing liquid inlet 130 to the absorbing liquid outlet 132 in FIG. 2 for explaining the weir plate 136 and the partition plate 138 according to this embodiment. It is explanatory drawing.

  As shown in FIG. 2, the oxidation tower 104 according to the present embodiment has, for example, a substantially cylindrical shape, and is connected to the bottom of the oxidation tower 104 via the communication pipe 106 near the bottom of the absorption tower 104. The absorption liquid inlet 130 and the absorption liquid outlet 132 connected to the circulation pump 120 are formed. Further, at the bottom of the oxidation tower 104, a partition wall 134 and two weir plates 136 are formed radially from the central axis of the oxidation tower 104 toward the outer periphery of the oxidation tower 104 (that is, in the radial direction of the oxidation tower 104). And two partition plates 138 are provided, and the weir plates 136 and the partition plates 138 are arranged alternately. The oxidation tower 104 has a gas-liquid mixing device 114 (not shown) for jetting oxidation air for oxidizing the oxide to have a predetermined angle with respect to the tangential direction of the oxidation tower 104. One or more are arranged.

  The unoxidized absorbent 110 flowing from the absorption tower 102 via the communication pipe 106 flows into the oxidation tower 104 from the absorbent inlet 130 and passes through the flow paths indicated by (1) to (7) in FIG. Then, it flows out from the absorption liquid outlet 132 to the circulation pump 120. As shown in FIG. 2, the flow of the absorption liquid in the oxidation tower 104 as viewed from above is determined depending on the flow direction of the absorption liquid and the flow of the absorption liquid for gas-liquid mixing ejected by the gas-liquid mixing device 114. The weir plate 136 and the partition plate 138 are provided at the bottom of the oxidation tower 104 so as to be substantially orthogonal to the flow of the absorbing liquid.

  As shown in FIG. 3, the weir plate 136 provided in the oxidation tower 104 according to the present embodiment is erected from the bottom of the oxidation tower 104 toward the top of the tower, and the height of the weir plate 136 is the partition wall. It is lower than the height C of 134. A plurality of partition plates 138 are provided between adjacent weir plates 136 such that the lower ends of the partition plates 138 are separated from the bottom of the oxidation tower 104. By providing the barrier plate 136 and the partition plate 138 in this way, the flow path opening 140 is generated in the upper portion of the barrier plate 136 and the lower portion of the partition plate 138.

  Note that the upper end of the barrier plate 136 may be higher than the lower end of the partition plate 138, or may be lower than the lower end of the partition plate 138. Further, the upper end of the barrier plate 136 may be positioned at the same height as the lower end of the partition plate 138.

  The weir plate 136 is a plate for making the absorption liquid flow and the bubble flow in the oxidation tower 104 positively upward to form bubbles. In FIG. 3, for example, in the section represented by a, by providing the weir plate 136, the bubble floating distance is not the liquid level height C from the bottom of the oxidation tower 104, but the height B of the flow path opening 140. It becomes. That is, the height B is a distance from the upper end of the barrier plate 136 to the liquid level. By providing the weir plate 136, it is possible to shorten the bubble floating distance, and it is possible to efficiently remove the bubbles.

  The partition plate 138 is a plate for further combining the bubbles floating by the barrier plate 136 and separating them more reliably. Since the flow of the absorbing liquid is directed downward by the partition plate 138, not only the influence of the flow of the absorbing liquid on the flow of bubbles can be reduced, but also the bubbles come into contact with the partition plate 138, thereby further dividing the partition. There is an effect that the bubbles easily rise as they are along the plate 138.

  In this way, by alternately installing the weir plates 136 and the partition plates 138 on the flow path of the absorbent, the absorbent that has flowed into the oxidation tower 104 from the absorbent inlet 130 is meandering in the vertical direction while absorbing the absorbent. It will flow to the outflow port 132.

  Subsequently, the flow of the absorbing liquid and the flow of bubbles in the oxidation tower 104 according to the present embodiment will be described in detail with reference to FIG. FIG. 4 is an explanatory diagram for explaining a dam plate and a partition plate provided in the oxidation tower according to the present embodiment.

  The absorbing liquid and the bubbles flowing through the flow path opening 140 located at the lower part of the partition plate 138 flow upward due to the barrier plate 136 in the section of FIG. The absorption liquid that has flowed upward becomes a downward flow by the partition plate 138 provided in the section b, but the flow of bubbles further rises by the partition plate 138 as described above. Thereby, bubbles are effectively removed. In addition, the bubbles that have not risen together with the absorbing liquid flow to the section a through the flow path opening 140 located at the lower part of the partition plate 138, but the absorbing liquid and the bubbles are separated by the barrier plate 136. Again, the flow is upward. The bubbles that have flowed upward are raised along the partition plate 138 by the partition plate 138 in the same manner as described above, and are effectively removed.

  Thus, by installing the weir plate 136 and the partition plate 138 at the bottom of the oxidation tower 104, not only the size of the bubbles increases, but also the distance that the bubbles need to rise is shortened. Many bubbles can be effectively degassed.

  In the above description, the case where the three dam plates 136 and the two partition plates 138 are installed has been described. However, the number of the dam plates 136 and the partition plates 138 according to the present embodiment is the above number. There is no limitation, and at least one sheet may be provided in the vicinity of the bottom of the oxidation tower 104 in accordance with the size of the oxidation tower 104, the amount of absorption liquid to be processed, and the like.

(Operation of the liquid phase oxidation wet desulfurization apparatus 10)
While the configuration of the liquid phase oxidation wet desulfurization apparatus 10 according to the present embodiment has been described above, the operation of the liquid phase oxidation wet desulfurization apparatus 10 according to the present embodiment will be described in detail.

  The raw material coke oven gas 108 introduced into the absorption tower 102 is brought into countercurrent contact with the post-oxidation absorption liquid 112 circulated from the oxidation tower 104 by the circulation pump 120, so that oxides such as hydrogen sulfide and hydrogen cyanide in the gas are formed. Absorbed and removed, and discharged from the top of the absorption tower 102 to the outside as the refined coke oven gas 126.

  The unoxidized absorbent 110 that has absorbed the oxide naturally flows into the oxidation tower 104 through the communication pipe 106 connected to the bottom of the absorption tower 102. The oxide in the unoxidized absorbing liquid 110 that naturally flows into the oxidation tower 104 is oxidized by the oxidizing air 118 ejected from the gas-liquid mixing device 114 to become the oxidized absorbing liquid 112. Further, the oxidizing air 118 that has not been used to oxidize the oxide becomes bubbles and exists in the absorbing solution.

  Bubbles existing in the absorption liquid flow upward by a weir plate 136 provided near the bottom of the oxidation tower 104, and move to the vicinity of the liquid level of the absorption liquid while forming bubbles with nearby bubbles. Furthermore, the bubbles move along the partition plate 138, move to the vicinity of the liquid surface of the absorbing liquid, and are removed from the absorbing liquid.

  The post-oxidation absorption liquid 112 from which bubbles have been removed (degassed) is sucked by the circulation pump 120 and dispersed in the absorption tower 102 by a spray nozzle provided at the top of the absorption tower 102. The bubbles removed from the absorbing solution are sent to the waste gas treatment as the oxidation tower waste gas 124.

(Second Embodiment)
Next, the liquid phase oxidation wet desulfurization apparatus 20 according to the second embodiment of the present invention will be described in detail with reference to FIGS.

(Configuration of liquid phase oxidation wet desulfurization apparatus 20)
FIG. 5 is an explanatory diagram for explaining the liquid-phase oxidation wet desulfurization apparatus according to the present embodiment. As shown in FIG. 5, the liquid phase oxidation wet desulfurization apparatus 20 according to this embodiment includes, for example, an absorption tower 202, an oxidation tower 204, and a communication pipe 206 that communicates the absorption tower 202 and the oxidation tower 204. Prepare.

  The absorption tower 202 absorbs and removes the oxide in the raw material coke oven gas 212, which is the gas to be treated, with an absorption liquid (absorbed liquid 216 after oxidation). The absorption liquid (non-oxidized absorption liquid 214) that has absorbed the oxide naturally flows into the oxidation tower 204 described later from the lower part of the absorption tower 202.

  The absorption tower 202 is provided with an absorption liquid spray nozzle at the top of the tower, and an absorption tower lower liquid reservoir in which the absorption liquid sprayed from the spray nozzle and absorbed the oxide is temporarily stored is formed at the bottom of the tower. Has been. In addition, a contact portion is provided between the spray nozzle and the absorption tower lower liquid reservoir so as to be filled with an appropriate filler and to counter-contact with the raw material coke oven gas 212 introduced from the gas introduction port. . Furthermore, a discharge port for discharging the purified coke oven gas 232 generated by removing the oxide from the raw material coke oven gas 212 is installed at the top of the absorption tower 202.

  The oxidation tower 204 regenerates the absorption liquid by blowing air into the absorption liquid (non-oxidation absorption liquid 214) that has absorbed the oxide supplied from the absorption tower 202 and oxidizing the oxidation target such as hydrogen sulfide and hydrogen cyanide. In addition, bubbles caused by unreacted air are removed from the absorbing solution. The oxidation tower 204 according to the present embodiment has a double shell structure, and is an internal tower 208 that is an oxidation section that oxidizes the absorption liquid naturally flowing from the absorption tower 202, and a floating separation section that floats and separates bubbles. It has a double structure with the outer tower 210.

  The inner tower 208 oxidizes the oxide contained in the unoxidized absorption liquid 214 naturally flowing in from the absorption tower 202 with air blown from a gas-liquid mixing device 218 described later to obtain an after-oxidation absorption liquid 216. The post-oxidation absorption liquid 216 is reused for spraying into the absorption tower 202 by a spray nozzle provided at the top of the absorption tower 202. The communication pipe 206 is directly connected to the inner tower 208, and the unoxidized absorbent 214 naturally flowing out from the bottom of the absorption tower 202 naturally flows directly into the inner tower 208 of the oxidation tower 204.

  The height of the inner tower 208 is lower than the height of the oxidation tower 204, and the upper end of the inner tower 208 is an opening. Further, a notch (not shown) is formed at one corner of the opening. The unoxidized absorption liquid 214 naturally flowing in from the absorption tower 202 accumulates in the inner tower 208 while being oxidized, and when the capacity of the inflowing unoxidized absorption liquid 214 becomes larger than the volume of the inner tower 208, the inner tower 208. It overflows from the opening formed at the upper end of the water, falls like a waterfall, and flows into the outer tower 210.

  A gas-liquid mixing device 218 including one or a plurality of air blowing nozzles is provided at the lower part of the inner tower 208. The gas-liquid mixing device 218 provided in the inner tower 208 according to the present embodiment is not particularly defined. For example, the gas-liquid mixing device described in Japanese Patent Application Laid-Open No. 62-192490 can be used. Is possible. In FIG. 5, only one gas-liquid mixing device 218 is illustrated, but the invention is not limited to the illustrated example, and a plurality of gas-liquid mixing devices 218 may be provided in the inner tower 208.

  In the gas-liquid mixing device 218, the oxidizing air 222 supplied from the blower 220 and the gas-liquid mixing absorbent 228 supplied from the circulation pump 226 are mixed and ejected into the inner tower 208. The ejected air oxidizes the oxide in the unoxidized absorption liquid 214 that naturally flows from the absorption tower 202, thereby converting the unoxidized absorption liquid 214 into an oxidized absorption liquid 216. A part of the air ejected from the gas-liquid mixing device 218 is not used for oxidizing the unoxidized absorbing liquid 214 but remains in the oxidized absorbing liquid 216 as bubbles. Some of the bubbles are diffused from the upper end of the inner tower 208 as the oxidation tower waste gas 230.

  The post-oxidation absorbing liquid 216 containing bubbles overflows from the upper end of the inner tower 208 and flows out to the outer tower 210 located on the outer periphery of the inner tower 208. The outer column 210 floats and separates the bubbles contained in the post-oxidation absorption liquid 216 flowing from the inner column 208.

  When the post-oxidation absorbing liquid 216 flows in, there is a drop between the upper end of the inner tower 208 and the liquid level of the outer tower 210, so the post-oxidation absorbing liquid 216 accumulated in the outer tower 210 contains the inner tower. The convection accompanying the inflow of the absorption liquid 216 after oxidation from 208 will occur. Due to this convection, bubbles existing in the absorption liquid 216 after oxidation rise to the liquid surface, and the bubbles can be efficiently removed from the absorption liquid 216 after oxidation.

  Further, the outer tower 210 is provided with a circulation pump 226 for circulating the absorption liquid in which the oxide is oxidized. The circulation pump 226 sucks the oxidized absorption liquid 216 from which bubbles have been removed from the outer tower 210 and circulates the absorption liquid 216 to the spray nozzle at the top of the absorption tower 202, and a part of the oxidized absorption liquid 216 is gas-liquid mixed. It supplies to the gas-liquid mixing apparatus 218 as the absorption liquid 228 for use. The circulation pump 226 sucks the post-oxidation absorption liquid 216 from the outer tower 210 so that the liquid level of the post-oxidation absorption liquid 216 in the outer tower 210 is lower than the height of the upper end of the inner tower 208.

  In the vicinity of the bottom of the outer tower 210, there are provided a weir plate 240 and a partition plate 242 for removing bubbles generated by the air ejected from the gas-liquid mixing device 218. These barrier plate 240 and partition plate 242 will be described in detail below.

  Bubbles separated from the absorption liquid 216 after oxidation in the outer tower 210 become oxidation tower waste gas 230, are discharged from the top of the oxidation tower 204, and are sent to waste gas treatment.

  The communication pipe 206 is a pipe that communicates the tower bottom of the absorption tower 202 with the tower bottom of the inner tower 208 of the oxidation tower 204, and an unoxidized absorption liquid 214 that has absorbed an oxide such as hydrogen sulfide in the absorption tower 202. It becomes a flow path for natural flow into the inner tower 208.

  Subsequently, the flow of the absorption liquid and the flow of bubbles in the oxidation tower 204 according to the present embodiment will be described in detail with reference to FIG. FIG. 6 is an explanatory diagram for explaining the absorption liquid and the flow of bubbles in the oxidation tower 204 according to the present embodiment.

  The unoxidized absorbent 214 that has absorbed the oxide contained in the raw coke oven gas 212 naturally flows from the absorption tower 202 through the communication pipe 206 to the inner tower 208 in the oxidation tower 204. The unoxidized absorbent 214 that naturally flows in is oxidized by the air ejected from the gas-liquid mixing device 218 while flowing toward the upper end of the inner tower 208, and becomes an oxidized absorbent 216 after oxidation. Air that has not been used to oxidize the oxide in the unoxidized absorbent 214 becomes bubbles and rises toward the upper end of the inner tower 208.

  The post-oxidation absorbing liquid 216 reaching the upper end of the inner column 208 overflows from a notch (not shown) provided at one corner of the upper end and falls to the outer column 210. Some of the bubbles contained in the post-oxidation absorption liquid 216 are discharged from the top of the oxidation tower 204 as oxidation tower waste gas, and some of the bubbles go to the outer tower 210 together with the post-oxidation absorption liquid 216. Inflow.

  The post-oxidation absorption liquid 216 overflowing from the notch of the inner tower 208 and flowing into the outer tower 210 flows along the outer periphery of the outer tower 210, while absorbing liquid discharge port 234 provided near the bottom of the outer tower 210. More discharged. Further, bubbles in the absorption liquid 216 after oxidation rise to the vicinity of the liquid surface by a weir plate 240 and a partition plate 242 described later, are removed from the absorption liquid 216 after oxidation, and are discharged out of the system as an oxidation tower waste gas 230. .

  Subsequently, the weir plate 240 and the partition plate 242 provided in the outer tower 210 according to the present embodiment will be described in detail with reference to FIGS. 7 and 8. In addition, in FIG. 7, although the case where the oxidation tower 204 which concerns on this embodiment has a substantially cylindrical shape is demonstrated, the shape of the oxidation tower 204 which concerns on this embodiment is not necessarily limited to a substantially cylindrical shape. .

  FIG. 7 is an explanatory diagram when the tower bottom of the oxidation tower 204 according to the present embodiment is viewed from above, and is an explanatory diagram for explaining the weir plate 240 and the partition plate 242 according to the present embodiment. FIG. 8 is an explanatory view showing the flow path extending from the inner tower 208 to the absorbing liquid outlet 234 in FIG. 7, and is an explanatory view for explaining the weir plate 240 and the partition plate 242 according to this embodiment. It is.

  As shown in FIG. 7, the oxidation tower 204 according to the present embodiment has a substantially cylindrical shape, and has a double shell structure. An inner tower 208 is located inside the oxidation tower 204 (near the central axis), and an outer tower 210 is located on the outer wall side of the oxidation tower 204. A communication pipe 206 is connected to the inner tower 208, and one or more gas-liquid mixing devices 218 are provided in the inner tower 208 so as to have a predetermined angle with respect to the tangential direction of the inner tower 208. Is provided.

  In the outer tower 210, a partition wall 238, three dam plates 240, and two partition plates 242 are formed radially from the central axis of the oxidation tower 204 toward the outer periphery of the oxidation tower 204 (the diameter of the oxidation tower 204. The weir plate 240 and the partition plate 242 are alternately arranged on the flow path of the absorbing liquid in the outer tower 210.

  The unoxidized absorbent 214 that has flowed in from the absorption tower 202 via the communication pipe 206 flows into the inner tower 208, and passes through the flow paths indicated by (1) to (7) in FIG. 234 flows out to the circulation pump 226. The absorption liquid supplied to the inner tower 208 from the communication pipe 206 is changed in the inner tower 208 depending on the inflow direction and the inflow speed into the inner tower 208 and the flow of the gas-liquid mixing absorption liquid ejected by the gas-liquid mixing device 218. Thus, the flow is along the circumference of the inner tower 208, and the bubbles 219 present in the absorption liquid also flow along the circumference of the inner tower 208 together with the absorption liquid. The absorbing liquid (1) overflowing from the notch (not shown) of the inner tower 208 and flowing into the outer tower 210 also flows along the circumference of the outer tower 210 in the outer tower 210 (2)- (7) The dam plate 240 and the partition plate 242 according to the present embodiment are provided in the vicinity of the bottom of the outer tower 210 so as to be substantially orthogonal to the flow of the absorbing liquid.

  As shown in FIG. 8, the weir plate 240 provided in the outer tower 210 according to the present embodiment is erected from the bottom of the outer tower 210 to the top of the tower, and the height of the weir plate 240 is a partition wall. It is lower than the height C of 238. A plurality of partition plates 242 are provided between the adjacent weir plates 240 so that the lower ends of the partition plates 242 are separated from the bottom of the outer tower 210. By providing the barrier plate 240 and the partition plate 242 in this manner, a flow path opening 244 is generated in the upper portion of the barrier plate 240 and the lower portion of the partition plate 242.

  The upper end of the barrier plate 240 may be higher than the lower end of the partition plate 242 or may be lower than the lower end of the partition plate 242. Further, the upper end of the barrier plate 240 may be positioned at the same height as the lower end of the partition plate 242.

  The weir plate 240 is a plate for making the flow of the absorbing liquid and the bubble flow in the outer tower 210 positively upward to make bubbles. For example, in the section represented by a in FIG. 8, by providing the weir plate 240, the bubble floating distance is not the liquid level height C from the bottom of the outer tower 210, but the height B of the flow path opening 244. It becomes. That is, the height B is a distance from the upper end of the barrier plate 240 to the liquid level. By providing the weir plate 240, it is possible to shorten the bubble floating distance, and it is possible to efficiently deaerate the bubbles.

  The partition plate 242 is a plate for further combining the bubbles floating by the barrier plate 240 and separating them more reliably. Since the flow of the absorbing liquid is directed downward by the partition plate 242, not only can the influence of the flow of the absorbing liquid on the flow of bubbles be reduced, but also the bubbles come into contact with the partition plate 242 to further reduce the partition. There is an effect that the bubbles easily rise along the plate 242 as they are.

  Thus, by alternately installing the weir plates 240 and the partition plates 242, the absorption liquid that flows in while falling from the inner tower 208 to the outer tower 210 flows to the absorption liquid outlet 234 while meandering in the vertical direction. As a result, bubbles are removed from the absorbing solution. In addition, by combining the weir plate 240 and the partition plate 242 at the bottom of the outer tower 210, not only the size of the bubbles increases, but also the distance that the bubbles need to rise becomes shorter, and more It becomes possible to deaerate bubbles effectively.

  In the above description, the case where the three dam plates 240 and the two partition plates 242 are installed has been described. However, the number of the dam plates 240 and the partition plates 242 according to the present embodiment is equal to the above number. It is not limited, and at least one piece may be provided in the vicinity of the bottom of the outer tower 210 in accordance with the size of the oxidation tower 204, the amount of absorption liquid to be processed, and the like. Further, the weir plate 240 and the partition plate 242 may be attached by a method other than radial (that is, the radial direction of the oxidation tower 204).

(Operation of the liquid phase oxidation wet desulfurization apparatus 20)
The configuration of the liquid phase oxidation wet desulfurization apparatus 20 according to the present embodiment has been described above. Next, the operation of the liquid phase oxidation wet desulfurization apparatus 20 according to the present embodiment will be described in detail.

  The raw material coke oven gas 212 introduced into the absorption tower 202 is in countercurrent contact with the post-oxidation absorption liquid 216 circulated from the oxidation tower 204 by the circulation pump 226, so that oxides such as hydrogen sulfide and hydrogen cyanide in the gas are formed. Absorbed and removed and discharged from the top of the absorption tower 202 to the outside as purified coke oven gas 232.

  The unoxidized absorption liquid 214 that has absorbed the oxide naturally flows into the inner tower 208 in the oxidation tower 204 through the communication pipe 206 connected to the bottom of the absorption tower 202. The oxide in the unoxidized absorbing liquid 214 that naturally flows in is oxidized by the oxidizing air 222 ejected from the gas-liquid mixing device 218 to become an oxidized absorbing liquid 216. Further, the oxidizing air 222 that has not been used to oxidize the oxide becomes bubbles and exists in the absorbing solution.

  With the inflow of the unoxidized absorption liquid 214 from the absorption tower 202, the liquid level of the absorption liquid in the inner tower 208 rises and overflows from the notch provided at the upper end of the inner tower 208 to the outer tower 210. Will come out. Due to the drop between the upper end of the inner tower 208 and the height of the liquid level in the outer tower 210, convection will occur in the post-oxidation absorbing liquid 216 accumulated in the outer tower 210. Due to the convection due to this drop, the bubbles in the oxidized absorbent 216 rise to the liquid surface.

  Further, the bubbles present in the absorption liquid flow upward by the weir plate 240 provided near the bottom of the outer tower 210 and move to the vicinity of the liquid level of the absorption liquid. Furthermore, the bubbles move along the partition plate 242 to move to the vicinity of the liquid surface of the absorption liquid, and are removed from the absorption liquid.

  The post-oxidation absorption liquid 216 from which bubbles have been removed is sucked by the circulation pump 226 and sprayed into the absorption tower 202 by a spray nozzle provided at the top of the absorption tower 202. The bubbles removed from the absorbing solution are sent to the waste gas treatment as the oxidation tower waste gas 230.

(First modification of the liquid phase oxidation wet desulfurization apparatus 20)
Then, the 1st modification of the liquid phase oxidation wet desulfurization apparatus which concerns on the 2nd Embodiment of this invention is demonstrated in detail, referring FIG. FIG. 9 is an explanatory diagram for explaining a first modification of the liquid phase oxidation wet desulfurization apparatus according to the second embodiment.

  In the liquid phase oxidation wet desulfurization apparatus 20 according to the second embodiment of the present invention shown in FIG. 5, the absorption tower 202 and the oxidation tower 204 are configured separately, but for example as shown in FIG. 9. The absorption tower and the oxidation tower may be integrally formed.

  As shown in FIG. 9, the liquid-phase oxidation wet desulfurization apparatus 30 according to this modification includes, for example, an absorption tower 302, an oxidation tower 304, and a communication pipe 306 that connects the absorption tower 302 and the oxidation tower 304. .

  The absorption tower 302 absorbs the oxide contained in the raw material coke oven gas 312 by the absorption liquid 316 after oxidation, and generates a purified coke oven gas 332. An oxidation tower 304 is integrally formed at the lower part of the absorption tower 302.

  Similar to the oxidation tower 204 according to the second embodiment, the oxidation tower 304 has a double-shell structure including an inner tower 308 and an outer tower 310, and the inner tower 308 of the oxidation tower 304 is formed from the bottom of the absorption tower 302. A communication pipe 306 is provided in a substantially vertical direction.

  About the gas-liquid mixing apparatus 318, the blower 320, and the circulation pump 326, it is respectively substantially the same as the gas-liquid mixing apparatus 218, the blower 220, and the circulation pump 226 in the liquid phase oxidation wet desulfurization apparatus 20 which concerns on the 2nd Embodiment of this invention. In order to achieve the same effect, detailed description is omitted.

  Even if the liquid-phase oxidation wet desulfurization apparatus 30 is configured as described above, bubbles can be efficiently removed from the post-oxidation absorbing liquid 316 in the outer tower 310 of the oxidation tower 304. Further, by integrally forming the absorption tower 302 and the oxidation tower 304, there is an advantage that the site area required for the installation of the entire coke oven gas refining facility can be reduced and the flow path configuration of the entire facility can be simplified. .

[Test example]
Next, the liquid phase oxidation wet desulfurization apparatus according to the present invention will be described while showing an actual test example of the liquid phase oxidation wet desulfurization apparatus according to the present invention. In addition, the test example shown below is an example for demonstrating the desulfurization apparatus based on this invention, Comprising: This invention is not necessarily limited to the following examples.

The liquid phase oxidation wet desulfurization apparatus shown in FIG. As test conditions, a coke oven gas containing 6 g / Nm ³ of hydrogen sulfide was introduced as a raw coke oven gas at 80000 Nm ³ / h from the lower part of an actual absorption tower having an inner diameter of 6.2 m and a height of 39 m. In addition, the oxidized absorbent was sprayed from the top of the actual absorption tower at 1750 m ³ / h and brought into countercurrent contact with the coke oven gas to absorb hydrogen sulfide in the coke oven gas.

  Coke oven gas with hydrogen sulfide absorbed to 0.15-0.2g / Nm3 is exhausted to the next process, and the absorbent is fed into the actual equipment through the communication pipe from the bottom of the actual equipment absorption tower. Naturally spilled into the tower.

In an actual tower with a diameter of 7.4 m and a height of 7.5 m, 1800 Nm ³ / h of air is blown from the bottom into the liquid by a blower with a blower to oxidize and regenerate the absorption liquid. Overflowed continuously. In addition, a total of six weir plates and partition plates were installed in the outer tower, and the absorbent was degassed.

  In this actual machine test, cavitation was not observed in the circulation pump connected to the outer tower, and it was found that deaeration was performed effectively.

  Thus, in the liquid phase oxidation wet desulfurization apparatus according to the present invention, it is possible to effectively remove the bubbles contained in the absorption liquid that absorbs the oxide in the coke oven gas, and the absorption tower The absorption liquid can be circulated by one pump without providing any new equipment other than the oxidation tower.

  As mentioned above, although preferred embodiment of this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to this example. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. Understood.

  For example, in the above-described first embodiment of the present invention, the case where the absorption tower 102 and the oxidation tower 104 are provided separately has been described. However, the absorption tower 102 and the oxidation tower 104 may be integrally formed.

It is explanatory drawing for demonstrating the liquid phase oxidation wet desulfurization apparatus which concerns on the 1st Embodiment of this invention. It is explanatory drawing for demonstrating the oxidation tower which concerns on the same embodiment. It is explanatory drawing for demonstrating the dam plate and partition plate provided in the oxidation tower which concern on the same embodiment. It is explanatory drawing for demonstrating the dam plate and partition plate provided in the oxidation tower which concern on the same embodiment. It is explanatory drawing for demonstrating the liquid phase oxidation wet desulfurization apparatus which concerns on the 2nd Embodiment of this invention. It is explanatory drawing for demonstrating the flow of the absorption liquid and bubble in the oxidation tower which concerns on the same embodiment. It is explanatory drawing for demonstrating the oxidation tower which concerns on the same embodiment. It is explanatory drawing for demonstrating the dam plate and partition plate provided in the oxidation tower which concern on the same embodiment. It is explanatory drawing for demonstrating the 1st modification of the liquid phase oxidation wet desulfurization apparatus which concerns on the same embodiment.

Explanation of symbols

10, 20, 30 Liquid phase oxidation wet desulfurization apparatus 102, 202, 302 Absorption tower 104, 204, 304 Oxidation tower 106, 206, 310 Communication pipe 108, 212, 312 Raw material coke oven gas 110, 214, 314 Unoxidized absorption liquid 112, 216, 316 Absorbed liquid after oxidation 114, 218, 318 Gas-liquid mixing device 116, 220, 320 Blower 118, 222, 322 Oxidizing air 120, 226, 326 Circulating pump 122, 228, 328 Absorbing liquid for gas-liquid mixing 124, 230, 330 Oxidizing tower waste gas 126, 232, 332 Refined coke oven gas 130 Absorption liquid inlet 132, 234 Absorption liquid outlet 134, 238 Partition 136, 240 Dam plate 138, 242 Partition plate 140, 244 Flow path opening Part 208,306 Inner tower 210,308 Outer tower 219

Claims (10)

An absorption tower for absorbing and removing oxides in the coke oven gas with an absorption liquid
An oxidation tower for oxidizing the oxide contained in the absorption liquid supplied from the absorption tower and regenerating and discharging the absorption liquid;
A liquid phase oxidation wet desulfurization apparatus comprising:
In the oxidation tower,
A weir plate standing from the bottom of the oxidation tower on the flow path of the absorption liquid from supply to discharge of the absorption liquid, and a lower end is separated from the bottom. The liquid-phase oxidation wet desulfurization apparatus is characterized in that at least one partition plate is provided alternately to each other, and the partition plates that float on the bubbles contained in the absorption liquid are provided. The inside of the oxidation tower is
The inner tower to which the height is lower than the oxidation tower and the upper end is an opening, and the absorption liquid is supplied from the absorption tower,
An outer tower located outside the inner tower and into which the absorbing liquid overflowing from the opening flows;
A double shell structure composed of
2. The liquid phase oxidation wet desulfurization apparatus according to claim 1, wherein the dam plate and the partition plate are provided on a flow path of the absorption liquid in the outer tower.   The liquid-phase oxidation wet desulfurization apparatus according to claim 2, wherein the absorbing liquid overflowing from the opening flows into the outer tower with a drop.   The liquid phase oxidation wet desulfurization apparatus according to any one of claims 1 to 3, wherein the barrier plate and the partition plate are arranged radially from a central axis of the oxidation tower.   5. The liquid phase oxidation wet desulfurization apparatus according to claim 1, wherein the oxidation tower further includes a gas-liquid mixing apparatus that ejects oxidation air that oxidizes the absorption liquid.   The liquid-phase oxidation wet desulfurization apparatus according to any one of claims 1 to 5, wherein the oxidation tower further includes a circulation pump that sucks the regenerated absorption liquid and circulates it into the absorption tower. .   The liquid phase oxidation wet desulfurization apparatus according to any one of claims 1 to 6, wherein the absorption tower and the oxidation tower are integrally formed.   The liquid phase oxidation wet desulfurization apparatus according to any one of claims 1 to 7, wherein an upper end of the barrier plate is located above a lower end of the partition plate.   The liquid phase oxidation wet desulfurization apparatus according to any one of claims 1 to 7, wherein an upper end of the dam plate is located below a lower end of the partition plate.   The liquid phase oxidation wet desulfurization apparatus according to any one of claims 1 to 7, wherein an upper end of the barrier plate is positioned at the same height as a lower end of the partition plate.

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