Constant-temperature direct oxidation treatment device

Abstract

The utility model relates to the technical field of acid gas purification equipment, in particular to a constant-temperature direct oxidation treatment device which comprises a static mixer, a preheater, a constant-temperature reactor, a sulfur condenser and a sulfur sealing tank, hydrogen sulfide and sulfur-containing harmful gas in the acid gas can be treated, the fluctuation resistance is high, the treatment efficiency is higher, and the application range is wider; almost all hydrogen sulfide in the acid gas is reacted, the acid gas treatment effect is good, the sulfur recovery rate is high, and the content of hydrogen sulfide and sulfur dioxide in tail gas is far lower than the national specified emission standard. The device is provided with the independent steam pocket, the steam pocket can recover a large amount of heat released by reaction in the constant-temperature reactor to generate sub-medium-pressure steam, the reaction temperature of the constant-temperature reactor is maintained, it is guaranteed that catalytic oxidation reaction in the constant-temperature reactor is normally and effectively carried out, and the temperature of the constant-temperature reactor can be indirectly adjusted by adjusting steam pressure at an outlet of the steam pocket; the removal efficiency and the treatment stability of hydrogen sulfide in the acid gas are ensured.

Description

Technical Field

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

[0002] At present, in the process of petrochemical, coal gasification or natural gas extraction, some acidic gases, that is, acidic gases containing harmful substances such as hydrogen sulfide and organic sulfur, are generated. They are highly toxic, corrosive and have a pungent odor, and direct discharge will cause serious pollution to the environment and do not meet the emission requirements. Therefore, it is necessary to purify the acidic gases. The purification process in the prior art usually uses an oxidation reaction to treat the acidic gas, converting the sulfur-containing harmful substances in the acidic gas into sulfur element; however, the current oxidation equipment usually has the problems of poor acid gas removal effect, short catalyst life, and low sulfur recovery rate. Therefore, based on the above problems, the prior art needs to be further improved. Utility Model Content

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

[0004] In order to solve the above technical problems, the technical solution provided by the utility model is as follows: a constant temperature direct oxidation treatment device is provided, comprising a static mixer, a preheater, a constant temperature reactor, a sulfur condenser and a sulfur sealing tank, wherein the head end of the static mixer is connected with an acid gas inlet and an air inlet, and the tail end is connected with the preheater, the tail end of the preheater is connected with the head end of the constant temperature reactor, the tail end of the constant temperature reactor is connected with the sulfur condenser, the tail end of the sulfur condenser is provided with a process gas outlet and a liquid sulfur outlet, and the liquid sulfur outlet is connected with the sulfur sealing tank.

[0005] Based on the above technical solution, the constant temperature reactor includes an outer cylinder, a reaction chamber and a heat exchange tube bundle. The top end of the outer cylinder is provided with a gas inlet, and the bottom end is provided with a gas outlet. The reaction chamber is arranged in the outer cylinder, and the heat exchange tube bundle is arranged in the reaction chamber. The reaction chamber is filled with at least one layer of catalyst, and the heat exchange tube bundle is provided with a flowing heat exchange liquid.

[0006] Based on the above technical solution, it also includes a steam drum, which is provided with a liquid pipeline and a steam pipeline. The end of the liquid pipeline is connected to the head end of the heat exchange tube bundle, and the end of the heat exchange tube bundle is connected to the head end of the steam pipeline.

[0007] On the basis of the above technical solution, the acid gas inlet is connected to the acid gas separation tank, and the air inlet is connected to the main fan.

[0008] Based on the above technical solution, a plurality of constant temperature reactors are provided, and the constant temperature reactors are arranged in series or in parallel.

[0009] Based on the above technical solution, the catalyst is arranged in three layers in the reaction chamber, including a direct oxidation catalyst layer filled in the upper layer, a hydrolysis Claus catalyst layer filled in the middle layer and a selective oxidation catalyst layer filled in the lower layer, and the mass ratio is 20%-30% / 35%-45% / 30%-40%.

[0010] Based on the above technical solution, the catalyst is arranged in the reaction chamber through a carrier structure, and the carrier structure includes a porcelain ball support layer, a wire mesh and a filling material. The porcelain ball support layer is filled with porcelain balls. The wire mesh is laid on both sides of the porcelain ball support layer and fixed on the inner wall of the 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.

[0011] Based on the above technical solution, an insulation coil is arranged between the reaction chamber and the gas outlet and is filled with low-pressure steam. The head end of the insulation coil is connected to the low-pressure steam inlet, and the tail end is connected to the low-pressure condensate outlet.

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

[0013] The utility model provides a constant temperature direct oxidation treatment device.

[0014] 1. The utility model provides a constant temperature direct oxidation reaction device, which can treat hydrogen sulfide and sulfur-containing harmful gases in acidic gas and acidic gas with a hydrogen sulfide concentration range of 0-100%, has strong anti-fluctuation ability, higher treatment efficiency, and a wider range of applications; almost all of the hydrogen sulfide in the acidic gas is reacted, the acidic gas treatment effect is good, the sulfur recovery rate is high, the hydrogen sulfide and sulfur dioxide contents in the tail gas are far lower than the national emission standards, and the environmental friendliness is strong.

[0015] 2. The present application is provided with an independent steam drum, which can recover a large amount of heat released by the reaction in the constant temperature reactor to generate sub-medium pressure steam, maintain the reaction temperature of the constant temperature reactor, and ensure that the catalytic oxidation reaction inside the constant temperature reactor proceeds normally and effectively. At the same time, by adjusting the steam pressure at the outlet of the steam drum, the temperature of the constant temperature reactor can be indirectly adjusted to ensure the removal efficiency of hydrogen sulfide in the acidic gas and the treatment stability.

[0016] 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. At the same time, it extends the service life of the catalyst, which can be up to 2-3 times that of traditional catalysts. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic structural diagram of the direct oxidation device in the utility model;

[0018] Figure 2 It is a partial cross-sectional view of the constant temperature reactor in the utility model;

[0019] Figure 3 It is a structural schematic diagram of the catalyst and carrier structure in the constant temperature reactor of the utility model; DETAILED DESCRIPTION

[0020] The utility model is further described below in conjunction with the accompanying drawings and embodiments:

[0021] 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.

[0022] 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.

[0023] like Figures 1 to 3 As shown, the utility model provides a constant temperature direct oxidation treatment device, including a static mixer 1, a preheater 2, a constant temperature reactor 3, a sulfur condenser 4 and a sulfur sealing tank 5, the head end of the static mixer 1 is connected with an acid gas inlet and an air inlet, and the tail end is connected with the preheater 2, the tail end of the preheater 2 is connected with the head end of the constant temperature reactor 3, the tail end of the constant temperature reactor 3 is connected with the sulfur condenser 4, the tail end of the sulfur condenser 4 is provided with a process gas outlet 41 and a liquid sulfur outlet 42, and the liquid sulfur outlet 42 is connected with the sulfur sealing tank 5.

[0024] The utility model provides a constant temperature direct oxidation reaction device, which can treat hydrogen sulfide and sulfur-containing harmful gas in acidic gas and acidic gas with a hydrogen sulfide concentration range of 0-100%, has strong anti-fluctuation ability, higher treatment efficiency and wider application range; almost all of the hydrogen sulfide in the acidic gas is reacted, the acidic gas treatment effect is good, the sulfur recovery rate is high, the hydrogen sulfide and sulfur dioxide contents in the tail gas are far lower than the national emission standards, and the environmental friendliness is strong.

[0025] Specifically, in the present application, the acid gas and oxygen supply gas, i.e., air, are introduced into the static mixer 1 for mixing, and then the mixed gas is preheated, and the inlet temperature of the constant temperature reactor 3 is controlled by adjusting the flow rate of the medium-pressure steam in the preheater 2; after the acid gas and air are preheated in the preheater 2, they enter the constant temperature reactor 3 for reaction. There is no heating stage in the constant temperature reactor 3, and the function is single-minded, the reaction space is larger, the processing efficiency is more stable, and the energy consumption is lower. In the constant temperature reactor 3, the acid gas and the air undergo a catalytic oxidation reaction at 180-280°C, oxidizing H2S to elemental sulfur while hydrolyzing the organic sulfur in the process gas, and the following reactions mainly occur: H2S+0.5SO2→1 / xS x +H2O; in order to realize the controllable oxidation of H2S in the acid gas, the heat generated in the constant temperature reactor can be taken out through the heat exchange tube bundle to avoid the catalyst from being deactivated due to excessive temperature and to increase its service life; the process gas after the oxidation reaction is condensed through the sulfur condenser 4, and the condensed process gas enters the next processing section from the process gas outlet 41 of the sulfur condenser 4, and the liquid sulfur enters the liquid sulfur pool 14 for storage after passing through the sulfur sealing tank 5 through the liquid sulfur outlet 42.

[0026] On the basis of the above technical solution, the constant temperature reactor 3 includes an outer cylinder 31, a reaction chamber 32 and a heat exchange tube bundle 33. The top of the outer cylinder 31 is provided with a gas inlet 34, and the bottom is provided with a gas outlet 35. The reaction chamber 32 is arranged in the outer cylinder 31, and the heat exchange tube bundle 33 is arranged in the reaction chamber 32. The reaction chamber 32 is filled with at least one layer of catalyst, and the heat exchange tube bundle 33 is provided with a flowing heat exchange liquid.

[0027] Preferably, the heat exchange tube bundle is provided with flowing medium-pressure boiler water from the distribution network; the medium-pressure boiler water enters the heat exchange tube bundle of the isothermal reactor, removes the heat generated by the reaction, maintains the temperature of the isothermal reactor at 280°C, and generates 1.7MPa saturated steam, which eventually enters the steam network. The heat exchange medium of the isothermal reactor in this application is water, which is different from the existing treatment process that uses oil as the heat exchange medium. Using water as the heat exchange medium is not only inexpensive, but also compared with using oil as the heat exchange medium, when using water as the heat exchange medium during the operation of the device, it is not only convenient to replace and the water can be discharged on the spot, and the treatment cost is also lower.

[0028] On the basis of the above technical solution, it also includes a steam drum 6, which is provided with a liquid pipeline 61 and a steam pipeline 62. The end of the liquid pipeline 61 is connected to the head end of the heat exchange tube bundle 33, and the end of the heat exchange tube bundle 33 is connected to the head end of the steam pipeline 62.

[0029] The present application is provided with an independent drum 6, which can recycle a large amount of heat released by the reaction in the constant temperature reactor to generate sub-medium pressure steam, maintain the reaction temperature of the constant temperature reactor 3, and ensure that the catalytic oxidation reaction inside the constant temperature reactor 3 is carried out normally and effectively. At the same time, by adjusting the outlet steam pressure of the drum 6, the temperature of the constant temperature reactor 3 can be indirectly adjusted to ensure the removal efficiency and treatment stability of hydrogen sulfide in the acidic gas. Specifically, the medium-pressure boiler water from the distribution network enters the heat exchange tube bundle 33 through the drum 6, and the heat generated during the direct oxidation reaction in the constant temperature reactor 3 is taken away in time. At the same time, the medium-pressure boiler water in the heat exchange tube bundle 33 absorbs heat and generates saturated steam, which enters the steam network through the drum 6. The head end and the 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.

[0030] On the basis of the above technical solution, the acid gas inlet is connected to the acid gas separator tank 7 , and the air inlet is connected to the main fan 8 .

[0031] The acid gas in the present application comes from the gas phase outlet of the reflux tank at the top of the desulfurization regeneration tower, and after passing through the acid gas separation tank 7 to remove excess water and other liquids, the acid gas and air are fully mixed in the static mixer 1 with the air provided by the main fan 8, and the liquid separated in the acid gas liquid separation tank 7 is discharged through the acid water pump. Specifically, the acid gas inlet is connected to the gas phase outlet of the acid gas liquid separation tank, and the air inlet is connected to the outlet of the main fan.

[0032] Based on the above technical solution, a plurality of constant temperature reactors 3 are provided, and the constant temperature reactors 3 are arranged in series or in parallel.

[0033] Depending on the actual working conditions, two constant temperature reactors can be designed to be connected in series or in parallel; if the hydrogen sulfide concentration in the source gas is high, series connection can be selected; if the hydrogen sulfide concentration is low, only one constant temperature reactor can be used; if the hydrogen sulfide concentration is low but the gas processing volume is large, two constant temperature reactors can be used in parallel; the acid gas treatment effect is better and the applicability is stronger.

[0034] Based on the above technical solution, the catalyst is arranged in three layers in the reaction chamber, including a direct oxidation catalyst layer 36 filled in the upper layer, a hydrolysis Claus catalyst layer 37 filled in the middle layer and a selective oxidation catalyst layer 38 filled in the lower layer, and the mass ratio is 20%-30% / 35%-45% / 30%-40%.

[0035] Specifically, the reactions occurring in each layer are as follows: the upper layer oxidizes the hydrogen sulfide in the process gas into sulfur, accompanied by some side reactions, and the reaction formula is: H2S+0.5O2=1 / xS x +H2O, S+O2=SO2, H2S+CO2=COS+H2O, 2H2S+CO2=CS2+2H2O; the middle layer is to hydrolyze COS and CS2 produced by the side reaction into H2S and promote the Claus reaction. The reaction formula is: COS+H2O=H2S+CO2, CS2+2H2O=2H2S+CO2, 2H2S+SO2=3 / 2S2+2H2O; the bottom layer is to oxidize the hydrogen sulfide in the process gas into sulfur and reduce the occurrence of side reactions. The reaction formula is: H2S+0.5O2=1 / XS x +H2O,S+O2=SO2.

[0036] In a preferred embodiment, the catalyst in the isothermal reactor 3 is provided with three layers, wherein the hydrolysis catalyst filled in the middle layer is a titanium-based catalyst, and the other two are iron-based catalysts; that is, three catalysts, namely, direct oxidation catalyst, hydrolysis Claus catalyst and selective oxidation catalyst, are provided for selection and matching, and the preferred catalyst loading sequence is: top layer: direct oxidation catalyst, which oxidizes the hydrogen sulfide in the process gas into sulfur, accompanied by some side reactions; middle layer: hydrolysis agent Claus catalyst, which hydrolyzes COS produced by the side reaction into H2S and promotes the Claus reaction; bottom layer: selective oxidation catalyst, which oxidizes the hydrogen sulfide in the process gas into sulfur, reducing the occurrence of side reactions. In addition, the loading amount and loading sequence of the catalyst can be designed according to the actual working conditions, and the loading sequence can be changed to effectively deal with the situation where the hydrogen sulfide concentration exceeds the design value when the equipment size is determined.

[0037] On the basis of the above technical solution, the catalyst is arranged in the reaction chamber 32 through a carrier structure, and the carrier structure includes a ceramic ball support layer 9, a wire mesh 10 and a filling material. The ceramic ball support layer 9 is filled with ceramic balls. The wire mesh 10 is laid on both sides of the ceramic ball support layer 9 and fixed on the inner wall of the reaction chamber 32. Filling material is also arranged between the ceramic balls and the wire mesh to prevent the ceramic balls and the catalyst from falling off.

[0038] More preferably, the bottom shape of the reaction chamber in the constant temperature reactor is similar to an inverted pot, so that the support effect is good and the support strength is also large; 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, while extending the service life of the catalyst, which can reach 2-3 times the service life of traditional catalysts. Specifically, the carrier structure can achieve stable support for the catalyst layer, and multiple layers of catalysts are arranged in the reaction chamber. A ceramic ball support layer is arranged at the top and bottom of the catalyst, and the middle multiple layers of catalysts are stacked in sequence. Through the multi-layer catalytic oxidation reaction, the treatment effect of the acidic gas is better; 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.

[0039] Based on the above technical solution, an insulation coil 11 is arranged between the reaction chamber 32 and the gas outlet 35 and is filled with low-pressure steam. The head end of the insulation coil 11 is connected to the low-pressure steam inlet 12, and the end is connected to the low-pressure condensate outlet 13.

[0040] By providing a heat preservation coil 11 between the bottom end of the reaction chamber 32 and the top end of the gas outlet 35, low-pressure steam is introduced into the heat preservation coil 11, so that the sulfur vapor after the reaction can be kept warm and heated, so that it can maintain a certain temperature before entering the sulfur condenser 4, avoiding the problem of sulfur blockage, and having excellent practical performance in the actual operation process.

[0041] The basic principles and main features of the present invention are shown and described above. For those skilled in the art, it is obvious that the present invention 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 present invention 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 present invention.

[0042] 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 constant temperature direct oxidation treatment device, characterized in that: The invention comprises a static mixer (1), a preheater (2), a constant temperature reactor (3), a sulfur condenser (4) and a sulfur sealing tank (5). The head end of the static mixer (1) is connected with an acid gas inlet and an air inlet, and the tail end is connected with the preheater (2). The tail end of the preheater (2) is connected with the head end of the constant temperature reactor (3). The tail end of the constant temperature reactor (3) is connected with the sulfur condenser (4). The tail end of the sulfur condenser (4) is provided with a process gas outlet (41) and a liquid sulfur outlet (42). The liquid sulfur outlet (42) is connected with the sulfur sealing tank (5).

2. A constant temperature direct oxidation treatment device according to claim 1, characterized in that: The constant temperature reactor (3) comprises an outer cylinder (31), a reaction chamber (32) and a heat exchange tube bundle (33); the top end of the outer cylinder (31) is provided with a gas inlet (34), and the bottom end is provided with a gas outlet (35); the reaction chamber (32) is arranged in the outer cylinder (31); the heat exchange tube bundle (33) is arranged in the reaction chamber (32); the reaction chamber (32) is filled with at least one layer of catalyst; and a flowing heat exchange liquid is arranged in the heat exchange tube bundle (33).

3. A constant temperature direct oxidation treatment device according to claim 2, characterized in that: The invention also comprises a steam drum (6), wherein the steam drum (6) is provided with a liquid pipeline (61) and a steam pipeline (62), wherein the end of the liquid pipeline (61) is connected to the head end of the heat exchange tube bundle (33), and the end of the heat exchange tube bundle (33) is connected to the head end of the steam pipeline (62).

4. A constant temperature direct oxidation treatment device according to claim 1, characterized in that: The acid gas inlet is connected to the acid gas separation tank (7), and the air inlet is connected to the main fan (8).

5. The constant temperature direct oxidation treatment device according to claim 1, characterized in that: A plurality of the constant temperature reactors (3) are provided, and the constant temperature reactors (3) are arranged in series or in parallel.

6. A constant temperature direct oxidation treatment device according to claim 2, characterized in that: The catalyst is arranged in three layers in the reaction chamber, including an upper layer filled with a direct oxidation catalyst layer (36), a middle layer filled with a hydrolysis Claus catalyst layer (37) and a lower layer filled with a selective oxidation catalyst layer (38), and the mass ratio is 20%-30% / 35%-45% / 30%-40%.

7. A constant temperature direct oxidation treatment device according to claim 2 or 6, characterized in that: The catalyst is arranged in a reaction chamber (32) via a carrier structure, the carrier structure comprising a ceramic ball support layer (9), a wire mesh (10) and a filling material, the ceramic ball support layer (9) is filled with ceramic balls, the wire mesh (10) is laid on both sides of the ceramic ball support layer (9) and is fixedly arranged on the inner wall of the reaction chamber (32), 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.

8. A constant temperature direct oxidation treatment device according to claim 2, characterized in that: An insulation coil (11) is arranged between the reaction chamber (32) and the gas outlet (35) and is filled with low-pressure steam. The head end of the insulation coil (11) is connected to the low-pressure steam inlet (12), and the tail end is connected to the low-pressure condensate outlet (13).

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