Selective oxidation treatment device

Abstract

The utility model relates to the technical field of acid gas purification equipment, in particular to a selective oxidation treatment device which comprises a selective oxidation preheater, a static mixer, a selective oxidation reactor, a selective sulfur oxide condenser and a first sulfur sealing tank, by improving the internal structure, hydrogen sulfide in acid gas can be selectively oxidized into elemental sulfur, the removal efficiency is high, the sulfur recovery rate is high, the treatment efficiency is more stable, and the content of hydrogen sulfide and sulfur dioxide in tail gas is far lower than the national specified emission standard. Meanwhile, the preheater and the reactor are independently arranged, so that the gas can be preheated to the required temperature before the reaction, the reactor has no heating stage, the function is specific, the reaction space is larger, the treatment efficiency is more stable, and the energy consumption is lower. The process gas and the air are respectively preheated, and the reaction temperature can be reached by preheating with less heat, so that the use amount of preheating steam is effectively saved, and the energy consumption is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of acid gas purification equipment, in particular to a selective oxidation treatment device. Background Art

[0002] In the current petrochemical, coal chemical, and coal-to-gas processes, most of the sulfur contained in the raw materials is usually converted into H2S, which is separated to form acid gas containing H2S; acid gas containing H2S is also often separated during the acid gas purification process. These acid gases are generally treated by a desulfurization process to convert as much H2S as possible into elemental sulfur. In the acid gas desulfurization process, a small amount of harmful sulfur-containing substances still exist in the gas after direct oxidation reaction treatment, so a selective oxidation reaction stage is also required. Currently commonly used selective oxidation reaction equipment often has unstable sulfur-containing substance treatment efficiency, poor removal effect, low sulfur recovery rate and high equipment energy consumption. Therefore, based on the above problems, the present application improves the selective oxidation treatment device. Utility Model Content

[0003] The purpose of the utility model is to provide a selective oxidation treatment device to solve the prior art problems existing in the above-mentioned background technology.

[0004] In order to solve the above technical problems, the technical solution provided by the utility model is as follows: a selective oxidation treatment device is provided, comprising a selective oxidation preheater, a static mixer, a selective oxidation reactor, a selective oxidation sulfur condenser and a first sulfur sealing tank, wherein the selective oxidation preheater is used for preheating process gas and air, the head end of the static mixer is connected to the end of the selective oxidation preheater, and the end is connected to the selective oxidation reactor, the end of the selective oxidation reactor is connected to the head end of the selective oxidation sulfur condenser, the end of the selective oxidation sulfur condenser is provided with a process gas outlet and a liquid sulfur outlet, and the liquid sulfur outlet is connected to the first sulfur sealing tank.

[0005] Based on the above technical solution, the selective oxidation preheater includes a process gas preheater and an air preheater. The process gas preheater and the air preheater are arranged in parallel. The end of the process gas preheater and the end of the air preheater are both connected to the head end of the static mixer.

[0006] Based on the above technical solution, the selective oxidation reactor includes an outer cylinder, a process gas inlet, a process gas outlet, a selective oxidation reaction chamber and a catalyst layer. The process gas inlet is arranged at the top of the outer cylinder, the process gas outlet is arranged at the bottom, the selective oxidation reaction chamber is arranged inside the outer cylinder, and the catalyst layer is arranged in the selective oxidation reaction chamber.

[0007] Based on the above technical solution, the catalyst layer is arranged in the selective oxidation reaction chamber through a supporting structure, and the supporting structure includes a porcelain ball supporting layer, a wire mesh and a filling material. The porcelain ball supporting layer is filled with porcelain balls and is arranged on both sides of the catalyst layer. The wire mesh is laid on both sides of the porcelain ball supporting layer and is fixed on the inner wall of the selective oxidation reaction chamber. Filling material is also arranged between the porcelain balls and the wire mesh to prevent the porcelain balls and the catalyst from falling off.

[0008] On the basis of the above technical solution, the selective sulfur oxidation condenser is filled with low-pressure steam, and a steam condenser is also provided on the selective sulfur oxidation condenser for cooling the steam.

[0009] Based on the above technical solution, it also includes a sulfur trap, which is arranged at the end of the selective sulfur oxidation condenser and connected to the process gas outlet, and the end of the sulfur trap is connected to the second sulfur sealing tank.

[0010] On the basis of the above technical solution, the first sulfur sealing tank and the second sulfur sealing tank are both connected to the liquid sulfur pool, and a steam coil is arranged at the bottom of the liquid sulfur pool.

[0011] Based on the above technical solution, it also includes a bypass pipeline, which is arranged in parallel with the selective oxidation treatment device.

[0012] The beneficial effects of the technical solution provided by the utility model are:

[0013] 1. The utility model provides a selective oxidation treatment device, which can selectively oxidize hydrogen sulfide in acidic gas into elemental sulfur by improving its internal structure, with high removal efficiency, more stable treatment efficiency, high sulfur recovery rate, and the content of hydrogen sulfide and sulfur dioxide in tail gas is far lower than the national emission standards. At the same time, the preheater and reactor in the present application are independently arranged, so that the gas can be preheated to the required temperature before the reaction, there is no heating stage in the reactor, the function is single-minded, the reaction space is larger, the treatment efficiency is more stable, and the energy consumption is low.

[0014] 2. In the present application, the selective oxidation preheater is divided into two parts: a process gas preheater and an air preheater, that is, the process gas and air are preheated separately and then mixed, so as to make full use of the heat of the upper reaction and avoid energy waste; only a small amount of heat is needed for preheating to reach the reaction temperature condition of the selective oxidation reactor, which can effectively save the amount of preheating steam and effectively reduce energy consumption.

[0015] 3. Compared with the shorter service life of traditional catalysts, the catalyst used in this application improves the catalytic efficiency and is not easy to accumulate sulfur, thereby extending the service life of the catalyst, which can be up to 2-3 times that of traditional catalysts. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a structural schematic diagram of the selective oxidation device in the utility model;

[0017] Figure 2 It is an internal cross-sectional view of the selective oxidation reactor in the utility model;

[0018] Figure 3 yes Figure 2 Section view at AA in the middle; DETAILED DESCRIPTION

[0019] The utility model is further described below in conjunction with the accompanying drawings and embodiments:

[0020] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0021] In the description of the present invention, it should be understood that the terms "left", "right", "front", "back", "top", "bottom", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.

[0022] like Figures 1 to 3 As shown, the utility model provides a selective oxidation treatment device, comprising a selective oxidation preheater, a static mixer 1, a selective oxidation reactor 2, a selective oxidation sulfur condenser 3 and a first sulfur sealing tank 4, wherein the selective oxidation preheater is used for preheating process gas and air, the head end of the static mixer 1 is connected to the end of the selective oxidation preheater, and the end is connected to the selective oxidation reactor 2, the end of the selective oxidation reactor 2 is connected to the head end of the selective oxidation sulfur condenser 3, the end of the selective oxidation sulfur condenser 3 is provided with a first process gas outlet 31 and a liquid sulfur outlet 32, and the liquid sulfur outlet 32 ​​is connected to the first sulfur sealing tank 4.

[0023] The present invention provides a selective oxidation treatment device, which can selectively oxidize hydrogen sulfide in acidic gas into elemental sulfur by improving its internal structure, with high removal efficiency, more stable treatment efficiency, high sulfur recovery rate, and the content of hydrogen sulfide and sulfur dioxide in tail gas is far lower than the national emission standard. At the same time, the preheater and reactor in the present application are independently arranged, so that the gas can be preheated to the required temperature before the reaction, there is no heating stage in the reactor, the function is single-minded, the reaction space is larger, the treatment efficiency is more stable, and the energy consumption is low.

[0024] Based on the above technical solution, the selective oxidation preheater includes a process gas preheater 5 and an air preheater 6. The process gas preheater 5 and the air preheater 6 are arranged in parallel, and the end of the process gas preheater 5 and the end of the air preheater 6 are both connected to the head end of the static mixer 1.

[0025] In this application, the selective oxidation preheater is divided into two parts: a process gas preheater 5 and an air preheater 6, that is, the process gas and the air are preheated separately, and then mixed, which can effectively reduce energy consumption, make full use of the heat of the upper reaction, and avoid energy waste. This is because the temperature of the process gas after the upper catalytic oxidation reaction is high. If it is mixed with air before preheating when entering the selective oxidation reaction, it will waste more heat and increase energy consumption; therefore, the process gas and the air are set to be heated separately, and only less heat is required to reach the inlet temperature condition of the selective oxidation reactor, which can save the preheating steam consumption, effectively reduce energy consumption and have a better reaction effect. Specifically, the process gas comes from the previous direct oxidation reaction section, and the oxidation air comes from the blower 13, that is, the blower is connected to the head end of the air preheater to provide air.

[0026] Based on the above technical solution, the selective oxidation reactor 2 includes an outer cylinder 21, a process gas inlet 22, a second process gas outlet 23, a selective oxidation reaction chamber 24 and a catalyst layer 25. The process gas inlet 22 is arranged at the top of the outer cylinder 21, the second process gas outlet 23 is arranged at the bottom, the selective oxidation reaction chamber 24 is arranged inside the outer cylinder 21, and the catalyst layer 25 is arranged in the selective oxidation reaction chamber 24.

[0027] Specifically, the process gas from the direct oxidation reaction device is preheated by the process gas preheater 5, and the oxidizing air is preheated by the air preheater 6, and then respectively introduced into the static mixer 1 for mixing. The mixed process gas enters the selective oxidation reactor 2 for selective oxidation reaction, that is, H2S is selectively oxidized into elemental sulfur under the action of the catalyst, and the reaction is H2S+1 / 2O2→1 / xS x+H2O; the above reaction is a thermodynamically complete reaction and can achieve a very high conversion rate. The process gas after the reaction is condensed by the selective sulfur oxidation condenser 3, and the condensed liquid sulfur enters the first sulfur sealing tank 4 through the liquid sulfur outlet 32, and the process gas enters the next processing section such as the thermal incineration section through the first process gas outlet 31. It should be noted that the head end and the end end mentioned above are defined according to the flow direction of the liquid or gas, which is only for the convenience of describing and understanding the present technical solution, and does not constitute a limitation to the present application.

[0028] On the basis of the above technical solution, the catalyst layer 25 is arranged in the selective oxidation reaction chamber 24 through a supporting structure, and the supporting structure includes a ceramic ball supporting layer 7, a wire mesh 8 and a filling material. The ceramic ball supporting layer 7 is filled with ceramic balls and is arranged on both sides of the catalyst layer 25. The wire mesh 8 is laid on both sides of the ceramic ball supporting layer 7 and is fixed on the inner wall of the selective oxidation reaction chamber 24. Filling material is also arranged between the ceramic balls and the wire mesh to prevent the ceramic balls and the catalyst from falling off.

[0029] Compared with the shorter service life of traditional catalysts, the catalyst used in this application improves the catalytic efficiency and is not easy to accumulate sulfur, thereby extending the service life of the catalyst, which can reach 2-3 times the service life of traditional catalysts. Specifically, a catalyst layer is arranged in the reaction chamber, and a ceramic ball support layer is arranged at the top and bottom of the catalyst. Through the selective oxidation reaction, the sulfur recovery rate is higher; more preferably, the filling material is ceramic fiber cotton, that is, the gap between the wire mesh and the ceramic ball is filled with ceramic fiber cotton to prevent the ceramic ball and the catalyst carried on the ceramic ball support layer from falling off.

[0030] On the basis of the above technical solution, the selective sulfur oxidation condenser 3 is filled with low-pressure steam, and a steam condenser 9 is further provided on the selective sulfur oxidation condenser 3 for cooling the steam.

[0031] The process gas enters the selective sulfur oxidation condenser 3 for cooling. In order to condense the sulfur vapor as much as possible, the selective sulfur oxidation condenser 3 operates at a relatively low temperature, which is achieved by producing low-pressure steam of 0.12MPa; at the same time, a steam condenser 9 is provided on the selective sulfur oxidation condenser 3, in which the steam can be condensed, and the pressure controller is adjusted by adjusting the speed of the fan on the steam condenser 9 to maintain the pressure of the steam, so as to achieve a continuous and stable cooling effect. The temperature corresponding to the steam at a pressure of 0.12MPa is 120°C, which is slightly higher than the freezing point of sulfur. The control system ensures that the temperature is within a safe range above the freezing point of sulfur. The condensed liquid sulfur directly enters the liquid sulfur pool through the first sulfur sealing tank, and the process gas enters the subsequent processing section.

[0032] On the basis of the above technical solution, a sulfur trap 10 is further included. The sulfur trap 10 is arranged at the end of the selective sulfur oxidation condenser 3 and communicated with the first process gas outlet 31 . The end of the sulfur trap 10 is communicated with the second sulfur enclosure tank 11 .

[0033] By providing the sulfur trap 10, the trace amount of liquid sulfur remaining in the process gas from the selective sulfur oxidation condenser 3 can be captured, and the treatment effect of the acid gas is better; specifically, the sulfur trap 10 is provided with a demister for capturing the trace amount of liquid sulfur remaining in the process gas, and the captured liquid sulfur is directly sent to the liquid sulfur pool 12 through the second sulfur sealing tank 11, and the process gas flows out through the gas outlet of the sulfur trap 10 and enters the next treatment section.

[0034] On the basis of the above technical solution, the first sulfur sealing tank 4 and the second sulfur sealing tank 11 are both connected to the liquid sulfur pool 12 , and a steam coil is arranged at the bottom of the liquid sulfur pool 12 .

[0035] By providing a liquid sulfur pool 12, liquid sulfur generated during the process gas treatment process is stored to facilitate subsequent further processing. Specifically, a small amount of hydrogen sulfide will be released during the storage of the liquid sulfur in the liquid sulfur pool 12, so this part of the overflow gas is purged to the next processing section for further processing, and the liquid sulfur in the liquid sulfur pool 12 is transported to the outside of the boundary area by a liquid sulfur pump; at the same time, a steam coil is provided at the bottom of the liquid sulfur pool 12, which is used to keep the temperature of the liquid sulfur above 130°C when necessary to avoid the solidification of the liquid sulfur.

[0036] Based on the above technical solution, it also includes a bypass pipeline, which is arranged in parallel with the selective oxidation treatment device.

[0037] By providing a bypass pipeline, the selective oxidation reactor in the selective oxidation device can be better protected, that is, according to the concentration of hydrogen sulfide in the process gas after treatment in the previous section, the process gas is selected to directly enter the next treatment section through the bypass pipeline for treatment and then enter the tail gas incineration device, so as to avoid damage to the selective oxidation reactor caused by excessively high hydrogen sulfide concentration or environmental pollution caused by poor treatment effect; at the same time, the process gas directly enters the incinerator through the bypass pipeline of the selective oxidation stage for subsequent treatment, which does not affect the normal acid gas treatment process, has good process stability and excellent treatment effect.

[0038] The basic principle and main features of the utility model are shown and described above. For those skilled in the art, it is obvious that the utility model is not limited to the details of the above exemplary embodiments. Therefore, the embodiments should be regarded as exemplary and non-restrictive. The scope of the utility model is limited by the appended claims rather than the above description. Therefore, it is intended to include all changes within the meaning and scope of the equivalent elements of the claims in the utility model.

[0039] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A selective oxidation treatment device, characterized in that: The invention comprises a selective oxidation preheater, a static mixer (1), a selective oxidation reactor (2), a selective oxidation sulfur condenser (3) and a first sulfur sealing tank (4), wherein the selective oxidation preheater is used for preheating process gas and air, the head end of the static mixer (1) is connected to the tail end of the selective oxidation preheater, and the tail end is connected to the selective oxidation reactor (2), the tail end of the selective oxidation reactor (2) is connected to the head end of the selective oxidation sulfur condenser (3), the tail end of the selective oxidation sulfur condenser (3) is provided with a first process gas outlet (31) and a liquid sulfur outlet (32), and the liquid sulfur outlet (32) is connected to the first sulfur sealing tank (4).

2. A selective oxidation treatment device according to claim 1, characterized in that: The selective oxidation preheater comprises a process gas preheater (5) and an air preheater (6); the process gas preheater (5) and the air preheater (6) are arranged in parallel; the end of the process gas preheater (5) and the end of the air preheater (6) are both connected to the head end of the static mixer (1).

3. A selective oxidation treatment device according to claim 1, characterized in that: The selective oxidation reactor (2) comprises an outer cylinder (21), a process gas inlet (22), a second process gas outlet (23), a selective oxidation reaction chamber (24), and a catalyst layer (25); the process gas inlet (22) is arranged at the top end of the outer cylinder (21), the second process gas outlet (23) is arranged at the bottom end, the selective oxidation reaction chamber (24) is arranged inside the outer cylinder (21), and the catalyst layer (25) is arranged in the selective oxidation reaction chamber (24).

4. A selective oxidation treatment device according to claim 3, characterized in that: The catalyst layer (25) is arranged in the selective oxidation reaction chamber (24) via a support structure, the support structure comprising a ceramic ball support layer (7), a wire mesh (8) and a filling material, the ceramic ball support layer (7) is filled with ceramic balls and is arranged on both sides of the catalyst layer (25), the wire mesh (8) is laid on both sides of the ceramic ball support layer (7) and is fixedly arranged on the inner wall of the selective oxidation reaction chamber (24), and a filling material is also arranged between the ceramic balls and the wire mesh to prevent the ceramic balls and the catalyst from falling off.

5. A selective oxidation treatment device according to claim 1, characterized in that: The selective sulfur oxidation condenser (3) is filled with low-pressure steam, and a steam condenser (9) is also provided on the selective sulfur oxidation condenser (3) for cooling the steam.

6. A selective oxidation treatment device according to claim 1, characterized in that: It also comprises a sulfur trap (10), wherein the sulfur trap (10) is arranged at the end of the selective sulfur oxidation condenser (3) and is connected to the first process gas outlet (31), and the end of the sulfur trap (10) is connected to the second sulfur sealing tank (11).

7. A selective oxidation treatment device according to claim 6, characterized in that: The first sulfur sealing tank (4) and the second sulfur sealing tank (11) are both connected to a liquid sulfur pool (12), and a steam coil is provided at the bottom of the liquid sulfur pool (12).

8. A selective oxidation treatment device according to any one of claims 1 to 7, characterized in that: The invention also comprises a bypass line, wherein the bypass line is arranged in parallel with the selective oxidation treatment device.

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