Removal agent, removal method and device for hydrogen sulfide gas

Abstract

According to the hydrogen sulfide gas removal agent, the removal method and the device, the hydrogen sulfide gas is treated in two stages by adopting the absorbent and the fixing agent, and the stability of the absorbent is enhanced and the oxidation and conversion of hydrogen sulfide are promoted by cooperating the compounded surfactant and the catalyst with the sodium hydroxide solution; wherein the use amount of the surfactant is 1-3wt% of the mass of the catalyst; sulfur ions are further fixed through calcium hydroxide under the action of an oxidizing agent and a porous adsorbent, the oxidizing agent is a strong oxidizing agent capable of generating sodium ions or calcium ions in a solution, the treatment burden of filtrate recycling is relieved, secondary generation and escape of hydrogen sulfide gas are inhibited, and the removal rate of hydrogen sulfide gas in tail gas is increased; the method is suitable for treating tail gas containing hydrogen sulfide in industrial production.

Description

Technical Field

[0001] The present invention relates to the field of waste gas treatment, and in particular to a hydrogen sulfide gas removal agent, removal method and device. Background Art

[0002] Large amounts of exhaust gas containing hydrogen sulfide are often generated in oil refining, natural gas processing, wastewater treatment, and chemical production (such as leather, papermaking, and rubber manufacturing). Hydrogen sulfide is a colorless, flammable, and highly toxic gas with a strong odor like rotten eggs. Long-term exposure to low concentrations of hydrogen sulfide can cause fatigue, memory loss, and respiratory inflammation, while short-term exposure to large amounts can lead to coma and death within hours. Due to its high toxicity, hydrogen sulfide is listed as a key monitored chemical and a highly toxic substance. Therefore, its removal is of great importance.

[0003] At present, the treatment methods of hydrogen sulfide are mainly divided into dry and wet methods. Among them, the dry method relies on porous materials such as carbon-based materials and molecular sieve adsorbents, but the removal effect is general. The regeneration of the adsorbent and the treatment of the waste liquid generated will cause secondary pollution, and it is not suitable for large-scale or high-humidity hydrogen sulfide gas. Patent CN116983813A discloses an iron oxyhydroxide desulfurizer, its composition, preparation method and application, and obtains a porous desulfurizer by a step-by-step reaction of double hydroxides and binder-free molding. However, the preparation method is complicated, and the calcium sulfate used as a skeleton instead of a binder may affect the molding of the desulfurizer during the preparation process, thereby affecting the penetration of hydrogen sulfide.

[0004] Existing wet processes generally convert the sulfur ions in hydrogen sulfide before recycling it. However, chemical absorption methods still suffer from unstable absorbent absorption and secondary hydrogen sulfide escape. Patent CN110876883A discloses a wet oxidation-reduction method for removing hydrogen sulfide from gases. This method uses a complex iron absorbent to convert hydrogen sulfide into hydrosulfide ions, which are then absorbed into the rich solution. The hydrosulfide ions are then regenerated through air oxidation to elemental sulfur. However, the absorbent preparation requirements are high, requiring strict control of parameters such as pH and iron concentration. The oxidation rate is slow, and to ensure absorbent stability and prevent side reactions during the reaction, complexing agent consumption increases. Summary of the Invention

[0005] To address the current issues of limited hydrogen sulfide treatment effectiveness, secondary hydrogen sulfide release, and complex hydrogen sulfide gas removal agent preparation, the present invention provides a hydrogen sulfide gas removal agent, removal method, and apparatus. This invention enhances absorbent stability, promotes hydrogen sulfide oxidation and conversion, reduces the processing burden of filtrate reuse, inhibits side reactions, and improves the removal rate of hydrogen sulfide in tail gas.

[0006] The specific technical solutions of the present invention are:

[0007] In a first aspect, the present invention provides a hydrogen sulfide gas remover, comprising an absorbent and a fixative, characterized in that the components of the absorbent are 15-30wt% of sodium hydroxide, 2-5wt% of a surfactant, and 1-5wt% of a catalyst; the components of the fixative are 20-40wt% of calcium hydroxide, 12-15wt% of an oxidant, and 11-18wt% of a porous adsorbent silica gel; the surfactant comprises one or more of sodium dodecyl sulfate, polyoxyethylene ether, sodium polyacrylate, and sodium carboxymethyl cellulose; the catalyst comprises one or more of composite iron-manganese oxide, cobalt oxide, and vanadium sulfate; and the oxidant comprises one or more of sodium peroxide, calcium peroxide, and sodium percarbonate.

[0008] In the remover of the present invention, the absorbent is enhanced in stability by introducing a surfactant, can maintain the uniformity of the system, reduce the surface tension of the gas-liquid interface, stabilize the foam at the gas-liquid interface, increase the gas-liquid contact area, and thus promote the absorption of the sodium hydroxide solution by hydrogen sulfide gas; however, if the dosage is too large, the mass transfer efficiency will be affected, the gas-liquid contact will be hindered, and the reaction rate will be reduced; among the surfactants that can be selected, sodium dodecyl sulfate and polyoxyethylene ether both form micelles by encapsulating hydrogen sulfide through their hydrophobic ends, thereby promoting mass transfer; however, if the dosage is too large, the micelle encapsulation will instead hinder the contact between hydrogen sulfide and the sodium hydroxide solution; sodium polyacrylate forms a hydrogen bond network with water molecules through carboxylate groups, which is beneficial to the dispersibility of the system; however, if the dosage is too large, the viscosity of the solution will increase, affecting the diffusion of hydrogen sulfide and the absorption of sodium hydroxide; the polymer chain of sodium carboxymethyl cellulose forms a three-dimensional network structure, which promotes gas-liquid contact by stabilizing bubbles at the gas-liquid interface; however, if the dosage is too large, steric hindrance will be generated, thereby hindering the mass transfer between gas and liquid.

[0009] Preferably, the mass ratio of the surfactant to the sodium hydroxide in the absorbent is 1-2.5:8-15.

[0010] In the remover of the present invention, the absorbent activates the surface active sites by introducing a catalyst, reduces the reaction activation energy, promotes the absorption of hydrogen sulfide gas, and inhibits the side reaction to produce thiosulfate radicals; the surfactant and the catalyst are compounded in the absorbent, and the synergistic effect of the two further promotes the absorption of hydrogen sulfide gas by the sodium hydroxide solution, thereby improving the conversion rate of hydrogen sulfide gas; however, if the amount is too large, the activity and reaction selectivity of the catalyst will be reduced, the dispersibility of the solution will be reduced, and the absorption efficiency of the sodium hydroxide solution for hydrogen sulfide gas will be affected; the iron-manganese two-component interface of the composite iron-manganese oxide in the optional catalyst will promote the absorption of hydrogen sulfide gas by the sodium hydroxide solution, thereby improving the conversion rate of hydrogen sulfide gas by the sodium hydroxide solution, thereby improving the conversion rate of hydrogen sulfide gas by the sodium hydroxide solution, thereby improving the conversion rate of hydrogen sulfide gas by the sodium hydroxide solution, It promotes electron transfer and gas-liquid mass transfer. When the dosage is too large, the composite iron-manganese oxide particles will agglomerate, the surface active sites will be reduced, the reaction rate will be reduced, and the absorption process will be affected. The cobalt active sites on the surface of cobalt oxide can activate oxygen molecules and hydroxyl radicals in the solution, promoting the conversion of hydrogen sulfide gas. If the dosage is too large, the solubility of cobalt oxide in the solution will be too high, affecting the dispersion of hydrogen sulfide gas in the solution. Under alkaline conditions, local acidic micro-areas can be formed on the surface of vanadium sulfate, which promotes the protonation of hydrogen sulfide gas. However, if the dosage is too large, vanadium ions will react with hydrogen sulfide gas, affecting the selectivity of the reaction.

[0011] Preferably, the amount of the surfactant in the absorbent is 1-3 wt% of the mass of the catalyst.

[0012] According to the present invention, an oxidant is added to a fixing agent, and the sulfide ions obtained after calcium hydroxide is treated with an absorbent in a solution environment react to generate solid precipitation; the sulfide ions generated in the absorption stage in the solution are oxidized into sulfate radicals, thereby effectively inhibiting the secondary generation and escape of hydrogen sulfide gas; and the optional sodium oxide, sodium percarbonate and calcium peroxide can generate sodium ions or calcium ions in the solution, thereby not significantly affecting the subsequent treatment and reuse of the filtrate without introducing additional impurities.

[0013] Furthermore, the present invention utilizes silica gel as a precipitation adsorbent, and its porous structure can adsorb and aggregate small particle precipitations generated during the reaction process, and can also adsorb hydrogen sulfide gas released during the reaction process, thereby preventing secondary escape of hydrogen gas. Silica gel can increase the local concentration in the solution through its large specific surface area and strong pore absorption effect, and combined with the effect of the oxidant, can accelerate the oxidation reaction rate and inhibit the generation of hydrogen sulfide or thiosulfate by-products.

[0014] Preferably, the mass ratio of the oxidant to the porous adsorbent silica gel in the fixing agent is 1.1-1.5:1.3-1.7.

[0015] Preferably, the porous adsorbent silica gel in the fixing agent has a particle size of 30-55 μm and a specific surface area of ​​300-600 m 2 / g.

[0016] In a second aspect, the present invention provides a method for removing hydrogen sulfide gas, comprising the following steps:

[0017] S1: In the absorption stage, the tail gas containing hydrogen sulfide is passed into a mixed solution of sodium hydroxide, surfactant and catalyst to obtain an absorption liquid, and part of the absorption liquid is reused in a spraying manner;

[0018] S2: Sulfide ion fixation stage, adding calcium hydroxide solid and oxidant to the absorption liquid produced in step S1, stirring thoroughly, and adding the precipitate produced by the aggregation of porous adsorbent silica gel;

[0019] S3: filtering the precipitate generated in step S2 to separate it into a solid phase and a liquid phase;

[0020] S4: The filtrate obtained by filtration in step S3 is returned to step S1 for absorption reaction, so that the filtrate can be recycled.

[0021] Preferably, the reaction conditions in step S1 are spraying density 11.2-14.2m 3 / (m 2 ·h), the reaction pH is 10-12, and the reaction temperature is 30-60°C.

[0022] Preferably, the reaction conditions in step S2 are reaction temperature of 20-50° C., stirring rate of 150-300 r / min, reaction time of 1-3 h, and reaction pH of 11-14.

[0023] In a third aspect, the present invention provides a device for use in a method for removing hydrogen sulfide gas, comprising an absorption tower 1, a settler 2, a filter 3 and a filtrate tank 4;

[0024] The absorption tower 1 is connected to the settler 2 via a 2# branch pipe 15 and is connected to the spray device 11 at the top of the absorption tower 1 via a 1# branch pipe 14;

[0025] The settler 2 is provided with an agitator 21, and the bottom is connected to the filter 3 via a delivery pump and a pipeline;

[0026] The filtrate tank 4 is provided with a wind shield 31 on the top, which is connected to the filter 3 through a pipeline, connected to the settler 2 through a 1# recycling pipe 41, and connected to the absorption tower 1 through a 2# recycling pipe 42.

[0027] The absorption tower 1, the settler 2, the filter 3 and the filtrate tank 4 are composed of components containing anti-corrosion material alumina ceramics.

[0028] In the above device, the absorption tower 1 is connected to the 1# branch pipe 14 to reuse the absorption liquid produced by the reaction in the form of spraying, which can make the reaction more complete and reduce the side reaction product hydrogen sulfide in the absorption liquid; the absorption tower 1 is also provided with a 1# online pH detector 12 and a 1# high and low liquid level gauge 13, which can provide real-time feedback on changes in reaction conditions and make timely adjustments; the settler 2 is funnel-shaped, wide at the top and narrow at the bottom, and is equipped with a feeding port 22 at the top. After the reaction raw materials are added, a dynamic vortex can be formed in the solution under the action of the agitator 21, and the precipitation is concentrated and discharged by the water pressure difference for filtration, which is beneficial to solid-liquid separation and reduces the impact on the treatment and reuse of the filtrate; the settler 2 is also provided with a 2# online pH detector 23 , 2# high and low liquid level gauges 24 are provided on the side wall to provide real-time feedback on changes in reaction parameters and make timely adjustments to reaction conditions; a wind shield 31 is provided on the top of the filtrate tank 4, which can effectively prevent the escape of waste gas generated by side reactions during solid-liquid separation, trap the gas in the reaction system, and effectively avoid air pollution; the filtrate transported to the settler 2 by the 1# return pipe 41 can be used as an acid-base regulator for the reaction in the settler 2; the filtrate is passed into the absorption tower 1 through the 2# return pipe 42 for recycling; since the entire reaction is carried out under alkaline conditions, in order to extend the service life of the equipment, the absorption tower 1, the settler 2, the filter 3 and the filtrate tank 4 are composed of components containing anti-corrosion material alumina ceramics.

[0029] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0030] The absorbent of the present invention adopts one or more surfactants selected from sodium dodecylsulfonate, polyoxyethylene ether, sodium polyacrylate and sodium carboxymethylcellulose, which synergistically act with one or more catalysts selected from composite iron-manganese oxide, cobalt oxide and vanadium sulfate, thereby enhancing the stability of the absorbent, promoting mass transfer between a sodium hydroxide solution and hydrogen sulfide gas, and accelerating the oxidation and conversion rate of hydrogen sulfide. The fixing agent adopts one or more oxidants selected from sodium peroxide, calcium peroxide and sodium percarbonate, thereby generating sodium ions or calcium ions in the solution, without introducing additional ionic impurities into the solution, and reducing the processing burden of filtrate recycling. At the same time, the porous adsorbent silica gel is utilized to accelerate the reaction rate of sulfur ion fixation, inhibit the occurrence of side reactions, prevent the secondary generation and escape of hydrogen sulfide gas, and improve the removal rate of hydrogen sulfide gas. Moreover, the reaction raw materials are easily available, and the method is suitable for being widely used in the treatment of hydrogen sulfide-containing tail gas in industrial production. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is a diagram of the device for removing hydrogen sulfide gas according to the present invention.

[0032] Figure 2 The present invention is a flow chart for removing hydrogen sulfide gas.

[0033] Attachment Figure 1Marked as: 1—absorption tower; 2—settler; 3—filter; 4—filtrate tank; 11—spraying device; 12—1# online pH detector; 13—1# high and low liquid level gauges; 14—1# branch pipe; 15—2# branch pipe; 21—agitator; 22—feeding port; 23—2# online pH detector; 24—2# high and low liquid level gauges; 31—wind shield; 41—1# return pipe; 42—2# return pipe. DETAILED DESCRIPTION

[0034] The present invention will be further described below with reference to the embodiments.

[0035] Overall embodiment

[0036] In a first aspect, the present invention provides a hydrogen sulfide gas remover, comprising an absorbent and a fixing agent, wherein the components of the absorbent are 15-30wt% of sodium hydroxide, 2-5wt% of a surfactant, and 1-5wt% of a catalyst; the components of the fixing agent are 20-40wt% of calcium hydroxide, 12-15wt% of an oxidant, and 11-18wt% of a porous adsorbent silica gel; the surfactant comprises one or more of sodium dodecyl sulfate, polyoxyethylene ether, sodium polyacrylate, and sodium carboxymethyl cellulose; the catalyst comprises one or more of composite iron-manganese oxide, cobalt oxide, and vanadium sulfate; and the oxidant comprises one or more of sodium peroxide, calcium peroxide, and sodium percarbonate.

[0037] Preferably, the mass ratio of the surfactant to the sodium hydroxide in the absorbent is 1-2.5:8-15.

[0038] Preferably, the amount of the surfactant in the absorbent is 1-3 wt% of the mass of the catalyst.

[0039] Preferably, the mass ratio of the oxidant to the porous adsorbent silica gel in the fixing agent is 1.1-1.5:1.3-1.7.

[0040] Preferably, the porous adsorbent silica gel in the fixing agent has a particle size of 30-55 μm and a specific surface area of ​​300-600 m 2 / g.

[0041] In a second aspect, the present invention provides a method for removing hydrogen sulfide gas, comprising the following steps:

[0042] S1: In the absorption stage, the tail gas containing hydrogen sulfide is introduced into the sodium hydroxide solution, surfactant and catalyst, and the reaction temperature is controlled at 30-60°C. At the same time, the pH value of the reaction is adjusted to 10-12 with the addition of liquid water to obtain an absorption liquid containing sodium sulfide and sodium hydrosulfide. A part of the absorption liquid is reused by spraying for further absorption reaction. The spray density is 11.2-14.2m 3 / (m2 h);

[0043] S2: Sulfide ion fixation stage, adding calcium hydroxide solid and oxidant to the absorption liquid produced in step S1, and adding porous adsorbent silica gel, controlling the reaction temperature at 20-50°C, the reaction pH at 11-14, the stirring rate at 150-300 r / min, and fully stirring for 1-3 hours to aggregate the generated precipitate containing elemental sulfur and calcium sulfate;

[0044] S3: Centrifugally separating the precipitate generated in step S2 into solid and liquid phases;

[0045] S4: A portion of the filtrate obtained by filtration in step S3, the main component of which is sodium hydroxide, is reused in step S1 for spraying and absorption reaction for recycling; the other portion is reused for sulfide ion fixation reaction and replenishing liquid for adjusting the reaction pH and liquid level position.

[0046] In a third aspect, the present invention provides a device for use in a method for removing hydrogen sulfide gas, comprising an absorption tower 1, a settler 2, a filter 3 and a filtrate tank 4;

[0047] The absorption tower 1 is connected to the settler 2 via a 2# branch pipe 15 and is connected to the spray device 11 at the top of the absorption tower 1 via a 1# branch pipe 14;

[0048] The settler 2 is provided with an agitator 21, and the bottom is connected to the filter 3 via a delivery pump and a pipeline;

[0049] The filtrate tank 4 is provided with a wind shield 31 on the top, which is connected to the filter 3 through a pipeline, connected to the settler 2 through a 1# recycling pipe 41, and connected to the absorption tower 1 through a 2# recycling pipe 42.

[0050] Preferably, the temperature of the absorption tower 1 is maintained below 60°C; the temperature of the settler 2 is maintained below 50°C; and the system pipeline is equipped with multiple temperature measuring points to maintain the temperature below 60°C.

[0051] Preferably, the reaction solution is introduced into the absorption tower 1 until the 1# online pH detector 12 reaches 10-12, and the 1# high and low liquid level gauges 13 display parameters are within the set range; the settler 2 waits until the 2# online pH detector 23 reaches 11-14, and the 2# high and low liquid level gauges 24 display parameters are within the set range.

[0052] Preferably, the settler 2 is funnel-shaped, wide at the top and narrow at the bottom, with a feeding port 22 at the top, and the agitator provided is an electric agitator. The speed of the agitator is adjustable, and the specific speed setting depends on the reaction needs; according to the specific embodiment of the present invention, it can be adjusted to 150r / min, 200r / min, 300r / min, etc.

[0053] Preferably, the filter 3 is a centrifugal device for dynamic separation of the solid phase and the liquid phase.

[0054] The absorption tower 1, the settler 2, the filter 3 and the filtrate tank 4 are composed of components containing anti-corrosion material alumina ceramics.

[0055] Example 1

[0056] The hydrogen sulfide gas is removed by the following steps:

[0057] S1: Add the following raw materials to the absorption tower reactor: 30wt% sodium hydroxide, 4wt% sodium dodecylsulfonate, and 1.5wt% cobalt oxide; pass the tail gas containing hydrogen sulfide into the absorption tower, control the temperature in the absorption tower to 30°C, and at the same time, use water to supplement the liquid phase and adjust the reaction pH value to 12 to obtain an absorption liquid containing sodium sulfide and sodium hydrosulfide. A part of the absorption liquid is transported to the top of the absorption tower through the 1# branch pipe for spraying and reuse for further absorption reaction. The spray density is 13.2m 3 / (m 2 h);

[0058] S2: Add the following raw materials from the feed port at the upper end of the settler: 30wt% calcium hydroxide, 15wt% sodium peroxide, and 15wt% silica gel; transport the absorption liquid to the settler through the 2# branch pipe. The reaction temperature is 30°C, the reaction pH is controlled at 12, the stirring rate is 200r / min, and the mixture is stirred for 2h to aggregate the resulting precipitate.

[0059] S3: centrifuging the precipitate through a filter to separate the solid and liquid phases;

[0060] S4: The filtrate obtained by filtration, the main component of which is sodium hydroxide, is transported to the top of the absorption tower through the 2# return pipe according to the reaction parameters fed back by the device in real time, and recycled in the form of spraying. The other part of the filtrate is transported to the precipitator through the 1# return pipe, which can be used as the reaction pH regulating liquid and the supplementary liquid for adjusting the reaction liquid level.

[0061] Example 2

[0062] The hydrogen sulfide gas is removed by the following steps:

[0063] S1: Add the following raw materials to the absorption tower reactor: 30wt% sodium hydroxide, 2wt% sodium lauryl sulfonate and 2wt% polyoxyethylene ether, and 1.5wt% cobalt oxide; pass the tail gas containing hydrogen sulfide into the absorption tower, control the temperature in the absorption tower to 30°C, and at the same time, use water to supplement the liquid phase and adjust the reaction pH value to 12 to obtain an absorption liquid containing sodium sulfide and sodium hydrosulfide. A part of the absorption liquid is transported to the top of the absorption tower through the 1# branch pipe for spraying and reuse for further absorption reaction. The spray density is 13.2m 3 / (m2 h);

[0064] S2: Add the following raw materials from the feed port at the upper end of the settler: 30wt% calcium hydroxide, 15wt% sodium peroxide, and 15wt% silica gel; transport the absorption liquid to the settler through the 2# branch pipe. The reaction temperature is 30°C, the reaction pH is controlled at 12, the stirring rate is 200r / min, and the mixture is stirred for 2h to aggregate the resulting precipitate.

[0065] S3: centrifuging the precipitate through a filter to separate the solid and liquid phases;

[0066] S4: The filtrate obtained by filtration, the main component of which is sodium hydroxide, is transported to the top of the absorption tower through the 2# return pipe according to the reaction parameters fed back by the device in real time, and recycled in the form of spraying. The other part of the filtrate is transported to the precipitator through the 1# return pipe, which can be used as the reaction pH regulating liquid and the supplementary liquid for adjusting the reaction liquid level.

[0067] Example 3

[0068] The hydrogen sulfide gas is removed by the following steps:

[0069] S1: Add the following raw materials to the absorption tower reactor: 30wt% sodium hydroxide, 3wt% sodium polyacrylate, and 1wt% cobalt oxide; pass the tail gas containing hydrogen sulfide into the absorption tower, control the temperature in the absorption tower to 60°C, and at the same time, use water to supplement the liquid phase and adjust the reaction pH value to 12 to obtain an absorption liquid containing sodium sulfide and sodium hydrosulfide. A portion of the absorption liquid is transported to the top of the absorption tower through the 1# branch pipe for spraying and reuse for further absorption reaction. The spray density is 13.2m 3 / (m 2 h);

[0070] S2: Add the following raw materials from the feed port at the upper end of the settler: 30wt% calcium hydroxide, 15wt% sodium peroxide, and 15wt% silica gel; transport the absorption liquid to the settler through the 2# branch pipe. The reaction temperature is 50°C, the reaction pH is controlled at 12, the stirring rate is 200r / min, and the mixture is stirred thoroughly for 1 hour to aggregate the resulting precipitate.

[0071] S3: centrifuging the precipitate through a filter to separate the solid and liquid phases;

[0072] S4: The filtrate obtained by filtration, the main component of which is sodium hydroxide, is transported to the top of the absorption tower through the 2# return pipe according to the reaction parameters fed back by the device in real time, and recycled in the form of spraying. The other part of the filtrate is transported to the precipitator through the 1# return pipe, which can be used as the reaction pH regulating liquid and the supplementary liquid for adjusting the reaction liquid level.

[0073] Example 4

[0074] The hydrogen sulfide gas is removed by the following steps:

[0075] S1: Add the following raw materials to the absorption tower reactor: 30wt% sodium hydroxide, 3.0wt% sodium carboxymethyl cellulose, and 3wt% cobalt oxide; pass the tail gas containing hydrogen sulfide into the absorption tower, control the temperature in the absorption tower to 60°C, and at the same time, use water to supplement the liquid phase and adjust the reaction pH value to 12 to obtain an absorption liquid containing sodium sulfide and sodium hydrosulfide. A portion of the absorption liquid is transported to the top of the absorption tower through the 1# branch pipe for spraying and reuse for further absorption reaction. The spray density is 13.2m 3 / (m 2 h);

[0076] S2: Add the following raw materials from the feed port at the upper end of the settler: 30wt% calcium hydroxide, 14wt% sodium peroxide, and 16wt% silica gel; transport the absorption liquid to the settler through the 2# branch pipe. The reaction temperature is 50°C, the reaction pH is controlled at 12, the stirring rate is 200r / min, and the mixture is stirred thoroughly for 1 hour to aggregate the resulting precipitate.

[0077] S3: centrifuging the precipitate through a filter to separate the solid and liquid phases;

[0078] S4: The filtrate obtained by filtration, the main component of which is sodium hydroxide, is transported to the top of the absorption tower through the 2# return pipe according to the reaction parameters fed back by the device in real time, and recycled in the form of spraying. The other part of the filtrate is transported to the precipitator through the 1# return pipe, which can be used as the reaction pH regulating liquid and the supplementary liquid for adjusting the reaction liquid level.

[0079] Example 5

[0080] The hydrogen sulfide gas is removed by the following steps:

[0081] S1: Add the following raw materials to the absorption tower reactor: 25wt% sodium hydroxide, 4wt% sodium dodecylsulfonate, and 4wt% vanadium sulfate; pass the tail gas containing hydrogen sulfide into the absorption tower, control the temperature in the absorption tower to 30°C, and at the same time, use water to supplement the liquid phase and adjust the reaction pH to 11 to obtain an absorption liquid containing sodium sulfide and sodium hydrosulfide. A portion of the absorption liquid is transported to the top of the absorption tower through the 1# branch pipe for spraying and reuse for further absorption reaction. The spray density is 12.2m 3 / (m 2 h);

[0082] S2: Add the following raw materials from the feed port at the upper end of the settler: 25wt% calcium hydroxide, 11wt% calcium peroxide, and 13wt% silica gel; transport the absorption liquid to the settler through the 2# branch pipe. The reaction temperature is 30°C, the reaction pH is controlled at 11, the stirring rate is 200r / min, and the mixture is stirred for 3 hours to aggregate the resulting precipitate.

[0083] S3: centrifuging the precipitate through a filter to separate the solid and liquid phases;

[0084] S4: The filtrate obtained by filtration, the main component of which is sodium hydroxide, is transported to the top of the absorption tower through the 2# return pipe according to the reaction parameters fed back by the device in real time, and recycled in the form of spraying. The other part of the filtrate is transported to the precipitator through the 1# return pipe, which can be used as the reaction pH regulating liquid and the supplementary liquid for adjusting the reaction liquid level.

[0085] Example 6

[0086] The hydrogen sulfide gas is removed by the following steps:

[0087] S1: Add the following raw materials to the absorption tower reactor: 30wt% sodium hydroxide, 5wt% polyoxyethylene ether, and 2.5wt% composite iron-manganese oxide; pass the tail gas containing hydrogen sulfide into the absorption tower, control the temperature in the absorption tower to 30°C, and at the same time, add water to the liquid phase to adjust the reaction pH value to 12 to obtain an absorption liquid containing sodium sulfide and sodium hydrosulfide. A portion of the absorption liquid is transported to the top of the absorption tower through the 1# branch pipe for spraying and reuse for further absorption reaction. The spray density is 14.2m 3 / (m 2 h);

[0088] S2: Add the following raw materials from the feed port at the upper end of the settler: 40wt% calcium hydroxide, 15wt% sodium peroxide, and 17wt% silica gel; transport the absorption liquid to the settler through the 2# branch pipe. The reaction temperature is 30°C, the reaction pH is controlled at 14, the stirring rate is 300r / min, and the mixture is stirred for 1.5h to aggregate the resulting precipitate.

[0089] S3: centrifuging the precipitate through a filter to separate the solid and liquid phases;

[0090] S4: The filtrate obtained by filtration, the main component of which is sodium hydroxide, is transported to the top of the absorption tower through the 2# return pipe according to the real-time feedback reaction parameters, and recycled in the form of spraying. The other part of the filtrate is transported to the precipitator through the 1# return pipe, which can be used as the reaction pH regulating liquid and the supplementary liquid for adjusting the reaction liquid level.

[0091] Example 7

[0092] The hydrogen sulfide gas is removed by the following steps:

[0093] S1: Add the following raw materials to the absorption tower reactor: 30wt% sodium hydroxide, 5wt% sodium dodecylsulfonate, and 2.5wt% vanadium sulfate; pass the tail gas containing hydrogen sulfide into the absorption tower, control the temperature in the absorption tower to 30°C, and at the same time, add water to the liquid phase to adjust the reaction pH value to 12 to obtain an absorption liquid containing sodium sulfide and sodium hydrosulfide. A portion of the absorption liquid is transported to the top of the absorption tower through the 1# branch pipe for spraying and reuse for further absorption reaction. The spray density is 14.2m 3 / (m 2 h);

[0094] S2: Add the following raw materials from the feed port at the upper end of the settler: 40wt% calcium hydroxide, 15wt% sodium percarbonate, and 17wt% silica gel; transport the absorption liquid to the settler through the 2# branch pipe. The reaction temperature is 30°C, the reaction pH is controlled at 14, the stirring rate is 300r / min, and the mixture is stirred thoroughly for 1.5h to aggregate the resulting precipitate.

[0095] S3: centrifuging the precipitate through a filter to separate the solid and liquid phases;

[0096] S4: The filtrate obtained by filtration, the main component of which is sodium hydroxide, is transported to the top of the absorption tower through the 2# return pipe according to the real-time feedback reaction parameters, and recycled in the form of spraying. The other part of the filtrate is transported to the precipitator through the 1# return pipe, which can be used as the reaction pH regulating liquid and the supplementary liquid for adjusting the reaction liquid level.

[0097] Comparative Example 1

[0098] The only difference between this comparative example and Example 1 is that sodium lauryl sulfate and cobalt oxide are not added in step S1, and sodium peroxide and silica gel are not added in step S2.

[0099] Comparative Example 2

[0100] The only difference between this comparative example and Example 1 is that cobalt oxide is not added in step S1.

[0101] Comparative Example 3

[0102] The only difference between this comparative example and Example 3 is that in step S1, 3 wt % of sodium polyacrylate is replaced by 6 wt % of sodium polyacrylate, and 1 wt % of cobalt oxide is replaced by 2 wt % of cobalt oxide.

[0103] Comparative Example 4

[0104] The only difference between this comparative example and Example 4 is that in step S1, 3 wt % of sodium carboxymethyl cellulose is replaced by 6 wt % of sodium carboxymethyl cellulose, and 1 wt % of cobalt oxide is replaced by 6 wt % of cobalt oxide.

[0105] Comparative Example 5

[0106] The only difference between this comparative example and Example 5 is that sodium lauryl sulfate is not added in step S1.

[0107] Comparative Example 6

[0108] The only difference between this comparative example and Example 6 is that calcium peroxide is not added in step S2.

[0109] Comparative Example 7

[0110] The only difference between this comparative example and Example 7 is that no silica gel is added in step S2.

[0111] Test Case

[0112] The removal effects of hydrogen sulfide gas and the main components of the generated precipitates of Examples 1 to 7 and Comparative Examples 1 to 7 were tested respectively, and the specific methods are as follows:

[0113] (1) Removal effect of hydrogen sulfide gas: The concentration change before and after is calculated by the real-time detection instrument installed at the outlet of the device to obtain the removal rate;

[0114] (2) Main components of the precipitate: The composition and content of the precipitate were analyzed by X-ray diffraction analysis and mass spectrometry.

[0115] The test results are shown in Table 1.

[0116] Table 1

[0117] Analyzing the data in Table 1, we can see that:

[0118] Compared to Comparative Example 1, Examples 1 to 7 all significantly improved the removal rate of hydrogen sulfide gas, converted unstable precipitated calcium sulfide into relatively stable elemental sulfur and calcium sulfate, and reduced the content of calcium sulfide. This indicates that the addition of a surfactant, catalyst, oxidant, and porous adsorbent to the two-stage method for treating hydrogen sulfide gas using a double alkaline solution can effectively enhance the absorption, oxidation, and conversion of hydrogen sulfide gas by the alkaline absorption solution, while also suppressing the occurrence of side reactions that lead to the secondary generation and escape of hydrogen sulfide gas.

[0119] Compared with Comparative Example 2, the removal rate of hydrogen sulfide gas in Example 2 is improved, indicating that the catalyst cobalt oxide can enhance the active sites and the selectivity of the reaction, so that the hydrogen sulfide gas and the sodium hydroxide solution can be more fully in contact, thereby enhancing the mass transfer efficiency; for Example 2, sodium dodecyl sulfate and polyoxyethylene ether are used as surfactants. Compared with Example 1, better results are also obtained, indicating that the synergistic effect of multiple surfactants and catalysts can further enhance the stability of the sodium hydroxide alkaline solution, accelerate the diffusion of hydrogen sulfide gas in the sodium hydroxide solution, and enhance the absorption of hydrogen sulfide gas by the sodium hydroxide solution.

[0120] Compared with Comparative Example 3, Example 3 can achieve a better level of hydrogen sulfide gas removal rate in a shorter reaction time under the action of reaction heating and the preferred amount of sodium polyacrylate and cobalt oxide. This shows that the increase in temperature can make the ion collision contact in the solution more sufficient, accelerate the reaction rate, and at the same time make the surfactant mainly act on reducing the surface tension of the gas-liquid interface, and cobalt oxide enhances the activity, all of which are aimed at promoting the penetration and absorption of hydrogen sulfide gas by sodium hydroxide solution without significantly increasing the viscosity of the solution; however, when the amount of sodium polyacrylate is too large, even under heating conditions, the viscosity of the solution cannot be avoided from increasing, which affects the diffusion of hydrogen sulfide gas in the sodium hydroxide solution. When the dispersibility deteriorates, the penetration effect is weakened, resulting in the absorbent being unable to better absorb hydrogen sulfide gas, thereby reducing the removal effect of hydrogen sulfide gas.

[0121] Compared with Comparative Example 4, Example 4 can achieve a better removal rate of hydrogen sulfide gas under the action of reaction heating and the preferred amount of sodium carboxymethyl cellulose and cobalt oxide. This shows that the increase in temperature can increase the ion collision reaction rate in the solution, and at the same time inhibit the spatial structure formed by sodium carboxymethyl cellulose at the gas-liquid interface to prevent gas-liquid contact from occurring, and cooperate with cobalt oxide to make the sodium hydroxide solution absorb hydrogen sulfide gas, thereby preventing hydrogen sulfide gas from escaping without reaction; however, when the amount of sodium carboxymethyl cellulose and cobalt oxide is too large, the three-dimensional network structure formed by the polymer chain of sodium carboxymethyl cellulose will obviously produce a steric hindrance effect, and cobalt oxide reduces the dispersibility of the solution, resulting in a weakened absorption effect of the absorbent, causing the hydrogen sulfide gas to remain on the surface of the sodium hydroxide solution and unable to diffuse and dissolve, directly affecting the removal effect of hydrogen sulfide gas.

[0122] Compared with Comparative Example 5, Example 5 improves the removal rate of hydrogen sulfide gas, which illustrates the synergistic effect of the surfactant sodium dodecyl sulfate and the catalyst vanadium sulfate, which can further enhance the permeation of the absorbent to hydrogen sulfide gas and enhance the mass transfer efficiency between gas and liquid; since vanadium sulfate can enhance activity, the reaction can reduce the amount of sodium hydroxide solution used; but the addition of an oxidant in an optimal amount to the fixing agent can oxidize the divalent sulfide ions in the solution into elemental sulfur and sulfate ions to form a stable precipitate, thereby preventing the precipitate from being converted into hydrogen sulfide gas, and avoiding the regeneration of hydrogen sulfide gas on the basis of removing the hydrogen sulfide gas. However, if the amount of oxidant is too low, the oxidation effect in the fixing reaction stage will be poor, and the secondary generation of hydrogen sulfide gas will not be suppressed, which will directly affect the removal rate of hydrogen sulfide.

[0123] Compared with Comparative Example 6, Example 6 adds an oxidant to the fixative, which enables the reaction to generate a more stable precipitate, thereby suppressing the side reaction that causes the secondary escape of hydrogen sulfide gas; the porous adsorbent silica gel added to the fixative, with its large specific surface area and good pore absorption effect, can adsorb more small particle precipitates, increase the local small area concentration in the solution, and make the reaction more complete under the action of the oxidant. At the same time, the aggregation of the precipitate can also effectively suppress the occurrence of side reactions, making the conversion effect more obvious.

[0124] Compared with Comparative Example 7, Example 7 adds porous adsorbent silica gel to the fixative, the stirring rate of the reaction in the settler is accelerated, the solution is dispersed more evenly, the intensity of the reaction in the system is increased, and the precipitate produced during the reaction is finely dispersed in the solution with stirring, while the silica gel adsorbs the small particle precipitate produced by the stirring reaction in the settler in the calcium hydroxide solution, thereby increasing the local concentration in the solution, increasing the contact area of ​​the reaction, and promoting oxidation. At the same time, it can also adsorb the hydrogen sulfide gas released by the side reaction and further react in the solution, thereby preventing the secondary escape of hydrogen sulfide gas and improving the removal effect of hydrogen sulfide gas.

[0125] Unless otherwise specified, the raw materials and equipment used in the present invention are commonly used in the art; the methods used in the present invention are conventional methods in the art unless otherwise specified.

[0126] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any way. Any simple modification, change and equivalent transformation made to the above embodiment based on the technical essence of the present invention still fall within the scope of protection of the technical solution of the present invention.

Claims

1. A hydrogen sulfide gas remover, comprising an absorbent and a fixing agent, characterized in that: The absorbent comprises 15-30 wt% of sodium hydroxide, 2-5 wt% of a surfactant, and 1-5 wt% of a catalyst; the fixative comprises 20-40 wt% of calcium hydroxide, 12-15 wt% of an oxidant, and 11-18 wt% of a porous adsorbent silica gel; the surfactant comprises one or more of sodium dodecyl sulfate, polyoxyethylene ether, sodium polyacrylate, and sodium carboxymethyl cellulose; the catalyst comprises one or more of composite iron-manganese oxide, cobalt oxide, and vanadium sulfate; and the oxidant comprises one or more of sodium peroxide, calcium peroxide, and sodium percarbonate.

2. A hydrogen sulfide gas removal agent according to claim 1, characterized in that: The mass ratio of the surfactant to the sodium hydroxide in the absorbent is 1-2.5:8-15.

3. The hydrogen sulfide gas removal agent according to claim 1, characterized in that: The amount of the surfactant in the absorbent is 1-3 wt% of the mass of the catalyst.

4. The hydrogen sulfide gas removal agent according to claim 1, characterized in that: The mass ratio of the oxidant in the fixing agent to the porous adsorbent silica gel is 1.1-1.5:1.3-1.

7.

5. The hydrogen sulfide gas removal agent according to claim 1, characterized in that: The particle size of the porous adsorbent silica gel in the fixing agent is 30-55 μm, and the specific surface area is 300-600 m 2 / g.

6. A method for removing hydrogen sulfide gas, characterized in that: The following steps are involved: S1: In the absorption stage, the tail gas containing hydrogen sulfide is passed into a mixed solution of sodium hydroxide, surfactant and catalyst to obtain an absorption liquid, and part of the absorption liquid is reused in a spraying manner; S2: Sulfide ion fixation stage, adding calcium hydroxide solid and oxidant to the absorption liquid produced in step S1, stirring thoroughly, and adding the precipitate produced by the aggregation of porous adsorbent silica gel; S3: filtering the precipitate generated in step S2 to separate it into a solid phase and a liquid phase; S4: The filtrate obtained by filtration in step S3 is returned to step S1 for absorption reaction, so that the filtrate can be recycled.

7. The method for removing hydrogen sulfide gas according to claim 6, characterized in that: The reaction conditions in step S1 are spraying density 11.2-14.2m 3 / (m 2 ·h), the reaction pH is 10-12, and the reaction temperature is 30-60°C.

8. The method for removing hydrogen sulfide gas according to claim 6, characterized in that: The reaction conditions in step S2 are as follows: reaction temperature of 20-50° C., stirring rate of 150-300 r / min, reaction time of 1-3 h, and reaction pH of 11-14.

9. The device used in the method for removing hydrogen sulfide gas according to any one of claims 6 to 8, characterized in that: It comprises an absorption tower (1), a settler (2), a filter (3) and a filtrate tank (4); The absorption tower (1) is connected to the settler (2) via a 2# branch pipe (15), and is connected to the spray device (11) at the top of the absorption tower (1) via a 1# branch pipe (14); The settler (2) is provided with an agitator (21), and the bottom is connected to the filter (3) via a delivery pump and a pipeline; The filtrate tank (4) is provided with a wind shield (31) on the top, connected to the filter (3) through a pipeline, connected to the settler (2) through a 1# recycling pipe (41), and connected to the absorption tower (1) through a 2# recycling pipe (42).

10. The device used in the method for removing hydrogen sulfide gas according to claim 9, characterized in that: The absorption tower (1), the settler (2), the filter (3) and the filtrate tank (4) are composed of components containing anti-corrosion material alumina ceramics.

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