Device and method for removing hydrogen sulfide and organic sulfur in sulfur-containing gas

Abstract

The invention relates to the technical field of environment-friendly purification, and discloses a device and a method for removing hydrogen sulfide and organic sulfur in sulfurous gas, the device comprises a pneumatic emulsification absorption tower and a bioreactor; a sprayer is arranged at the top of the pneumatic emulsification absorption tower and is used for spraying alkali liquor to convert hydrogen sulfide in the sulfur-containing gas into sulfide, and crude desulfurized gas is obtained; a desulfurization flora is arranged in the biological aerobic reactor and is used for converting sulfide into elemental sulfur; a gas-liquid separation tank is also arranged outside the pneumatic emulsification absorption tower, and an atomizing nozzle is arranged above the gas-liquid separation tank and is used for spraying a desulfurizing agent to remove hydrogen sulfide and organic sulfur in the crude desulfurized gas. When the device and the method are used for treating the high-sulfur-content gas, the purification capacity is high, hydrogen sulfide and organic sulfur in the sulfur-containing gas can be removed at the same time, the content of H2S in the purified gas is lower than 4 mg / m < 3 >, the content of the organic sulfur is lower than 20 mg / m < 3 >, and the generation rate of elemental sulfur is larger than 95%.

Description

Technical Field

[0001] The invention relates to the technical field of environmental protection purification, and in particular to a device and method for removing hydrogen sulfide and organic sulfur from sulfur-containing gas. Background Art

[0002] Hydrogen sulfide is highly toxic, corrosive and has a foul odor. It is an atmospheric pollutant that must be eliminated or controlled. It is the main sulfur component in natural gas, coke oven gas, refinery gas, semi-water gas and biogas. Its presence not only causes corrosion of equipment and pipelines, catalyst poisoning, but also seriously threatens personal safety.

[0003] Typical processes include the Claus process, iron oxide process, liquid absorption process and wet oxidation process. These traditional physical and chemical methods generally require high temperature and high pressure, or consume a large amount of chemicals and catalysts, with high investment and operating costs. The technology of removing hydrogen sulfide by microbial methods has become a research hotspot in recent years. Its basic principle is to dissolve H2S in water and remove it from acidic gases by the oxidation of H2S by microorganisms. Compared with traditional physical and chemical methods, microbial methods have mild reaction conditions, greatly reduced consumption of chemicals and energy, low operating costs, and no secondary pollution, so they have great development prospects.

[0004] According to the existence form of microorganisms in waste gas treatment, the treatment methods can be divided into two categories: biological scrubbing (suspended state) and biological filtration (fixed state). The biological scrubbing method uses a microbial absorption liquid composed of microorganisms, nutrients and water to treat H2S waste gas. Its typical forms include biological scrubbers such as spray towers, bubbling towers and perforated plate towers. The biological filtration method uses solid particles containing microorganisms to absorb H2S. Its typical forms include biological filter beds composed of materials such as soil and compost. Among them, the most typical forms are biological filter tanks and biological trickling filters.

[0005] The representative Shell-Paques biodesulfurization technology is suitable for sulfur production of 0.05-50t / d and gas flow rate>1.0×10 7 m 3 / d, pressure range 0.1-10MPa, H2S volume fraction 5.0×10 -5 -1 acid gas purification is a good choice both technically and economically for gas purification with large flow and medium to low H2S content.

[0006] However, the biological method also has the following problems: slow desulfurization rate, high removal efficiency for low-concentration H2S gas, unstable removal efficiency for high-concentration H2S gas, inability to meet gas purification processes with high purification requirements, good removal efficiency for inorganic sulfides such as H2S, but poor removal efficiency for organic sulfides, etc.

[0007] Therefore, there is an urgent need to find an economical and effective technology for removing hydrogen sulfide and organic sulfur, especially a resource-based process that can simultaneously recover sulfur. Summary of the invention

[0008] The purpose of the present invention is to overcome the problems of unstable removal efficiency of high-concentration sulfur-containing gas by biological methods, poor organic sulfur removal efficiency, slow desulfurization rate and low yield of elemental sulfur in the prior art, and to provide a device and method for removing hydrogen sulfide and organic sulfur from sulfur-containing gas.

[0009] In order to achieve the above-mentioned object, the first aspect of the present invention provides a device for removing hydrogen sulfide and organic sulfur from sulfur-containing gas, wherein the device comprises a pneumatic emulsification absorption tower and a bioreactor;

[0010] Wherein, a sprayer is arranged at the top of the pneumatic emulsification absorption tower for spraying alkali solution to convert hydrogen sulfide in the sulfur-containing gas into sulfide and obtain crude desulfurized gas;

[0011] Wherein, the biological aerobic reactor is provided with a desulfurization bacteria group for converting sulfide into elemental sulfur;

[0012] A gas-liquid separation tank is also arranged outside the pneumatic emulsification absorption tower, and an atomizing nozzle is arranged above the gas-liquid separation tank for spraying a desulfurizing agent to remove hydrogen sulfide and organic sulfur in the crude desulfurized gas.

[0013] A second aspect of the present invention provides a method for removing hydrogen sulfide and organic sulfur from sulfur-containing gas, wherein the method comprises subjecting the sulfur-containing gas to a rough desulfurization treatment, a biological oxidation treatment and a fine desulfurization treatment in the device described in the present invention.

[0014] Through the above technical solution, the present invention achieves the following beneficial technical effects:

[0015] (1) The present invention uses a combined process of alkaline solution absorption-biological oxidation desulfurization-triazine desulfurization agent fine desulfurization to treat high-sulfur gas. The purification capacity is high and hydrogen sulfide and organic sulfur in the sulfur-containing gas can be removed simultaneously, so that the H2S content in the purified gas is less than 4 mg / m 3 , organic sulfur content is less than 20mg / m 3 .

[0016] (2) The present invention adopts a pneumatic emulsification absorption tower to replace the traditional scrubbing tower (with low mass transfer efficiency), and utilizes low-temperature plasma technology to stimulate the growth of desulfurization microorganisms and the accumulation of extracellular sulfur, which significantly improves the efficiency of biological conversion / catalytic reaction, completely converts hydrogen sulfide in sulfur-containing gas into elemental sulfur, increases the yield of elemental sulfur, maintains system stability, and enhances the desulfurization effect. The generation rate of elemental sulfur is greater than 95%.

[0017] (3) The entire process has high purification efficiency, wide adaptability, easy operation and maintenance, good environmental benefits, and realizes the recovery of sulfur resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a device for removing hydrogen sulfide and organic sulfur from sulfur-containing gas.

[0019] Description of Reference Numerals

[0020] 01. Sulfur-containing gas 02. Liquid desulfurizer 03. Purified gas after desulfurization

[0021] 04. Packing absorption tower 11. Pneumatic emulsification absorption tower 12. Gas-liquid separation tank

[0022] 13. Rich liquid pump 14. Bioreactor 15. Sedimentation tank

[0023] 16. Centrifuge 17. Barren liquid pump 18. Solution pump

[0024] 19. Low temperature plasma treatment device DETAILED DESCRIPTION

[0025] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0026] In order to achieve the above-mentioned object, the first aspect of the present invention provides a device for removing hydrogen sulfide and organic sulfur from sulfur-containing gas, wherein the device comprises a pneumatic emulsification absorption tower and a bioreactor;

[0027] Wherein, a sprayer is arranged at the top of the pneumatic emulsification absorption tower for spraying alkali solution to convert hydrogen sulfide in the sulfur-containing gas into sulfide and obtain crude desulfurized gas;

[0028] Wherein, the biological aerobic reactor is provided with a desulfurization bacteria group for converting sulfide into elemental sulfur;

[0029] A gas-liquid separation tank is also arranged outside the pneumatic emulsification absorption tower, and an atomizing nozzle is arranged above the gas-liquid separation tank for spraying a desulfurizing agent to remove hydrogen sulfide and organic sulfur in the crude desulfurized gas.

[0030] In the present invention, the desulfurizing bacteria are selected from at least one of Thiobacillus denitrificans, Thiobacillus thiosulfuri and Thiobacillus napolinum. The above bacteria can be obtained commercially.

[0031] In the present invention, the pneumatic emulsification absorption tower is provided with an air outlet on the top, an air inlet and a liquid discharge port on the bottom, a sprinkler on the upper end, and a cyclone on the lower end. The sulfur-containing gas enters from the cyclone at the lower end of the tower body, forming a high-speed rotary upward airflow, which forms a reverse contact with the alkali solution flowing down the middle of the tower body. The gas rotary cuts the alkali solution at a high speed, and the circulating liquid is chopped into smaller and smaller pieces. The gas and liquid are fully mixed to form a stable emulsion layer. After the hydrogen sulfide in the sulfur-containing gas is absorbed by the alkali solution through pneumatic emulsification, the hydrogen sulfide content is greatly reduced, and the roughly desulfurized gas is discharged from the air outlet at the upper end of the tower body and enters the gas-liquid separation tank.

[0032] In the present invention, there is no particular limitation on the position where the sulfur-containing gas enters the pneumatic emulsification absorption tower. For example, the air inlet can be set at the upper end of the pneumatic emulsification absorption tower, or it can be set at the lower end of the pneumatic emulsification absorption tower. Preferably, the sulfur-containing gas enters from the cyclone at the lower end of the pneumatic emulsification absorption tower, so that the gas and liquid are fully mixed to form a stable emulsion layer, improve the gas-liquid mass transfer efficiency, and at the same time, the sulfur-containing gas is more fully in reverse contact with the alkali solution sprayed on the top of the pneumatic emulsification absorption tower, and the reaction and absorption are more thorough.

[0033] In the present invention, the gas-liquid separation tank is provided with a desulfurizing agent inlet and a gas outlet at the top, and a solid clear liquid outlet at the bottom. The liquid triazine desulfurizing agent enters the gas-liquid separation tank from the atomizing nozzle at the top of the gas-liquid separation tank, so that the hydrogen sulfide and organic sulfur content in the crude desulfurized gas is further reduced, and the purified gas after fine desulfurization is discharged from the gas outlet at the top of the gas-liquid separation tank.

[0034] According to some embodiments of the present invention, a low-temperature plasma treatment device is further provided outside the biological aerobic reactor to induce the growth of sulfur-oxidizing bacteria in the biological aerobic reactor.

[0035] According to some embodiments of the present invention, a solution pump is further provided between the biological aerobic reactor and the low-temperature plasma treatment device.

[0036] In the present invention, part of the solution in the bioreactor is pumped out by a solution pump and enters the low-temperature plasma treatment device, and is returned to the bioreactor after being treated by the low-temperature plasma treatment device.

[0037] According to some embodiments of the present invention, the device further comprises a rich liquid pump, a sedimentation tank, a centrifuge and a lean liquid pump.

[0038] Preferably, the rich liquid pump is connected to the discharge port of the pneumatic emulsification absorption tower and the water inlet of the biological aerobic reactor respectively; the inlet of the sedimentation tank is connected to the overflow port of the biological aerobic reactor, and the discharge port of the sedimentation tank is connected to the centrifuge; the lean liquid pump is connected to the outlet of the sedimentation tank and the upper end of the pneumatic emulsification absorption tower respectively.

[0039] In the present invention, the bioreactor is an airlift internal circulation bioreactor, which is covered with a guide tube, and air enters the bioreactor from the ventilation pipe at the bottom. The alkali solution that absorbs hydrogen sulfide is pressed into the water inlet of the bioreactor through the rich liquid pump, and the effluent flows out from the overflow port to the sedimentation tank.

[0040] In the present invention, a drain port is provided below the sedimentation tank, and the settled sulfur solution is sent to a centrifuge through the drain port to separate sulfur, and the regenerated alkali solution is returned to the absorption tower through a lean liquid pump.

[0041] In the present invention, in order to describe in more detail the removal process of hydrogen sulfide and organic sulfur in sulfur-containing gas, as shown in FIG. Figure 1 As shown, the device of the present invention is composed of a pneumatic emulsification absorption tower 11, a gas-liquid separation tank 12, a bioreactor 14, a low-temperature plasma treatment device 19, a sedimentation tank 15, a centrifuge 16, a lean liquid pump 17, a rich liquid pump 13 and a solution pump 18. The accelerated sulfur-containing gas 01 enters from the air inlet at the lower end of the pneumatic emulsification absorption tower 11 at a certain angle, and forms a reverse contact with the alkali solution flowing down the middle of the tower body. After being absorbed by the alkali solution, it is discharged from the gas outlet at the upper end of the pneumatic emulsification absorption tower 11 and enters the gas-liquid separation tank 12. The liquid desulfurizer 02 enters from the atomizing nozzle above the gas-liquid separation tank 12 and contacts and reacts with the purified gas of the rough desulfurization. A small amount of hydrogen sulfide and organic sulfur in the purified gas of the rough desulfurization are further removed, and the purified gas 03 obtained after fine desulfurization is discharged from the gas outlet of the gas-liquid separation tank 12. The alkali solution that has absorbed hydrogen sulfide is pressed into the water inlet of the bioreactor 14 through the rich liquid pump 13, and air 04 enters the bioreactor 14 from the ventilation pipe at the bottom. Under the air aeration and the biocatalytic action of the microbial desulfurization bacteria, the soluble sulfide reacts with oxygen to generate elemental sulfur, and the alkali solution is regenerated and flows out from the overflow port to the sedimentation tank 15. The settled sulfur solution is sent to the centrifuge 16 through the discharge port of the sedimentation tank 15 to separate the sulfur, and the regenerated alkali solution is returned to the pneumatic emulsification absorption tower 11 through the lean liquid pump 17. Part of the solution in the bioreactor 14 is pumped out by the solution pump 18, and is returned to the bioreactor 14 after being treated by the low-temperature plasma treatment device 19.

[0042] A second aspect of the present invention provides a method for removing hydrogen sulfide and organic sulfur from sulfur-containing gas, wherein the method comprises subjecting the sulfur-containing gas to a rough desulfurization treatment, a biological oxidation treatment and a fine desulfurization treatment in the device described in the present invention.

[0043] According to some embodiments of the present invention, the method comprises the following steps:

[0044] (1) subjecting the sulfur-containing gas to a rough desulfurization treatment in a pneumatic emulsification absorption tower included in the device to obtain a sulfide absorption rich liquid and a rough desulfurized gas;

[0045] (2) subjecting the sulfide absorption rich liquid to biological oxidation treatment in a bioreactor included in the device to obtain elemental sulfur;

[0046] (3) The crude desulfurized gas is subjected to fine desulfurization treatment in a gas-liquid separation tank included in the device to obtain purified gas.

[0047] In the present invention, after the sulfur-containing gas is fully absorbed by the alkali liquid in the pneumatic emulsification absorption tower, the alkali liquid containing sulfide (the rich liquid containing sulfide) is obtained; the alkali liquid containing sulfide is discharged from the lower end of the pneumatic emulsification absorption tower and enters the bioreactor through the rich liquid pump, and under the biocatalytic action of the biological desulfurization bacteria group, the soluble sulfide in the alkali liquid containing sulfide is converted into elemental sulfur, and at this time, the solution discharged from the outlet of the bioreactor is the regeneration liquid containing sulfur; the regeneration liquid containing sulfur enters the discharge port of the sedimentation tank and is sent to the centrifuge, and the solid-liquid separation is carried out in the centrifuge to obtain biological sulfur and supernatant (the supernatant is the regeneration alkali liquid); the supernatant is returned to the pneumatic emulsification absorption tower through the lean liquid pump for recycling.

[0048] According to some embodiments of the present invention, the method of crude desulfurization treatment includes: using alkaline solution to convert hydrogen sulfide in the sulfur-containing gas into sulfide to obtain sulfide absorption rich liquid and crude desulfurized gas.

[0049] Preferably, the alkali solution is an alkaline solution containing sodium; more preferably, the concentration of the alkali solution is 5-30 g / L and the pH value is 8-11; more preferably, the alkali solution is selected from at least one of Na2CO3, NaOH and NaHCO3.

[0050] According to some embodiments of the present invention, the biological oxidation treatment method includes: using a desulfurization bacteria group to convert the sulfide in the sulfide absorption rich liquid into elemental sulfur.

[0051] Preferably, the desulfurizing bacteria group is selected from at least one of Thiobacillus denitrificans, Thiobacillus thiosulfurans and Thiobacillus naples.

[0052] According to some embodiments of the present invention, the method further comprises using a low-temperature plasma treatment device included in the device to induce treatment of part of the desulfurization bacteria population in the bioreactor included in the device.

[0053] Preferably, the conditions of the induction treatment include: a discharge voltage of 50V-500V, a discharge power of 30W-600W, and a discharge time of 5min-100min.

[0054] In the present invention, the low-temperature plasma treatment device does not directly induce treatment on the desulfurization bacteria in the bioreactor, but a part of the desulfurization bacteria solution in the bioreactor is pumped out by the solution pump between the bioreactor and the low-temperature plasma treatment device, enters the low-temperature plasma treatment device, and is returned to the bioreactor after discharge stimulation by the low-temperature plasma treatment device.

[0055] In the present invention, when the conditions of the induction treatment meet the above range, it can stimulate the growth of desulfurization microorganisms and the accumulation of extracellular sulfur, significantly improve the efficiency of bioconversion / catalytic reaction, and increase the yield of elemental sulfur; when the conditions of the induction treatment do not meet the above range, it will cause the death of desulfurization microorganisms.

[0056] According to some embodiments of the present invention, the method of fine desulfurization treatment includes: removing hydrogen sulfide and organic sulfur in the crude desulfurized gas using a desulfurizer to obtain purified gas;

[0057] Preferably, the desulfurizing agent consists of solvent A, solvent B and water;

[0058] Preferably, based on the total mass of the desulfurizer, the content of the solvent A is 70wt%-90wt%, the content of the solvent B is 5wt%-20wt%, and the content of the water is 5wt%-10wt%;

[0059] Preferably, the solvent A is selected from at least one of dimethylisopropanolamine, 3-ethoxypropylamine, and amine-aldehyde condensation reaction products of N,N-dihydroxyethylaniline and formaldehyde; and the solvent B is selected from glycerol and / or N-methylpyrrolidone.

[0060] In the present invention, when the composition of the desulfurizer and the content of each substance meet the above-mentioned limited range, the technical effect of fast reaction speed with hydrogen sulfide and organic sulfur and high desulfurization efficiency is achieved; when the composition of the desulfurizer and the content of each substance do not meet the above-mentioned range, the desulfurizer will be easily degraded and the desulfurization efficiency will be low.

[0061] According to some embodiments of the present invention, the sulfur-containing gas is selected from at least one of natural gas, oilfield associated gas, synthesis gas and biogas.

[0062] Preferably, based on the volume of the sulfur-containing gas, the content of hydrogen sulfide in the sulfur-containing gas is 0.1 vol%-15 vol%, and the content of organic sulfur is 50-500 mg / m 3 .

[0063] In the present invention, the organic sulfur mainly includes a mixture of carbonyl sulfide, carbon disulfide and sulfide.

[0064] According to a particularly preferred embodiment of the present invention, the present invention provides a method for removing hydrogen sulfide and organic sulfur from sulfur-containing gas, the specific steps comprising:

[0065] The hydrogen sulfide content in the sulfur-containing gas is 0.1-15% (volume fraction) and the organic sulfur content is 50-500 mg / m 3 The concentration of alkali solution in the pneumatic emulsification absorption tower 11 is 15-25g / L, and the desulfurizer (the desulfurizer is composed of 70-90wt% triazine, 5-20wt% solvent (the solvent is selected from propylene glycol and / or N-methylpyrrolidone) and 5-10wt% water) is sprayed into the gas-liquid separation tank 12; in the bioreactor 14, the desulfurization bacteria are selected from at least one of denitrifying Thiobacillus, Thiobacillus excreta and Thiobacillus naples; in the low-temperature plasma treatment device 19, the discharge voltage is 100-400V, the discharge power is 150-600W, and the discharge time is 30-100min.

[0066] The present invention will be described in detail below through examples.

[0067] The hydrogen sulfide content was determined by iodine titration.

[0068] The organic sulfur content (calculated as the total content of carbonyl sulfide, carbon disulfide and sulfide) was determined by gas chromatography-flame photometry (GC-FPD).

[0069] The elemental sulfur production rate is the percentage of the mass of elemental sulfur in the lean solution to all sulfur elements in the rich solution.

[0070] All raw materials are commercially available.

[0071] Example 1

[0072] according to Figure 1 The device shown is used to remove hydrogen sulfide and organic sulfur from sulfur-containing gas.

[0073] The hydrogen sulfide content in the sulfur-containing gas is 1% (volume fraction) and the organic sulfur content is 100 mg / m 3The concentration of alkali solution in the pneumatic emulsification absorption tower 11 is 15g / L, and a desulfurizing agent (composed of 80wt% triazine (amine-aldehyde condensation reaction product of dimethylisopropanolamine and formaldehyde), 10wt% solvent (propylene glycol) and 10wt% water) is sprayed into the gas-liquid separation tank 12; in the bioreactor 14, the desulfurizing bacteria are a composite bacteria of Thiobacillus excreta and Thiobacillus denitrificans; in the low-temperature plasma treatment device 19, the discharge voltage is 100V, the discharge power is 150W, and the discharge time is 30min. The hydrogen sulfide content in the purified gas 03 is 0, and the organic sulfur content is less than 10mg / m 3 The elemental sulfur generation rate is 99.2%.

[0074] Example 2

[0075] according to Figure 1 The device shown is used to remove hydrogen sulfide and organic sulfur from sulfur-containing gas.

[0076] The hydrogen sulfide content in the sulfur-containing gas is 1% (volume fraction) and the organic sulfur content is 100 mg / m 3 The concentration of alkali solution in the pneumatic emulsification absorption tower 11 is 15g / L, and a desulfurizing agent (composed of 80wt% triazine (amine-aldehyde condensation reaction product of 3-ethoxypropylamine and formaldehyde), 10wt% solvent (propylene glycol) and 10wt% water) is sprayed into the gas-liquid separation tank 12; in the bioreactor 14, the desulfurizing bacteria are a composite bacteria of Thiobacillus excreta and Thiobacillus denitrificans; in the low-temperature plasma treatment device 19, the discharge voltage is 200V, the discharge power is 350W, and the discharge time is 50min. The hydrogen sulfide content in the purified gas 03 is 0, and the organic sulfur content is less than 5mg / m 3 The elemental sulfur generation rate is 98.5%.

[0077] Example 3

[0078] according to Figure 1 The device shown is used to remove hydrogen sulfide and organic sulfur from sulfur-containing gas.

[0079] The hydrogen sulfide content in the sulfur-containing gas is 1% (volume fraction) and the organic sulfur content is 100 mg / m 3 The concentration of alkali solution in the pneumatic emulsification absorption tower 11 is 15g / L, and a desulfurizer (composed of 80wt% triazine (amine-aldehyde condensation reaction product of N,N-dihydroxyethylaniline and formaldehyde), 10wt% solvent (propylene glycol) and 10wt% water) is sprayed into the gas-liquid separation tank 12; in the bioreactor 14, the desulfurization bacteria are a composite bacteria of Thiobacillus excreta and Thiobacillus denitrificans; in the low-temperature plasma treatment device 19, the discharge voltage is 200V, the discharge power is 300W, and the discharge time is 50min. The hydrogen sulfide content in the purified gas 03 is 0, and the organic sulfur content is less than 8mg / m 3 The elemental sulfur generation rate is 98.7%.

[0080] Example 4

[0081] according to Figure 1 The device shown is used to remove hydrogen sulfide and organic sulfur from sulfur-containing gas.

[0082] The hydrogen sulfide content in the sulfur-containing gas is 5% (volume fraction) and the organic sulfur content is 200 mg / m 3 The concentration of alkali solution in the pneumatic emulsification absorption tower 11 is 20g / L, and a desulfurizing agent (composed of 80wt% triazine (amine-aldehyde condensation reaction product of dimethylisopropanolamine and formaldehyde), 15wt% solvent (N-methylpyrrolidone) and 5wt% water) is sprayed into the gas-liquid separation tank 12; in the bioreactor 14, the desulfurizing bacteria community is a composite community of sulfur-excreting Thiobacillus and denitrifying Thiobacillus; in the low-temperature plasma treatment device 19, the discharge voltage is 200V, the discharge power is 300W, and the discharge time is 30min. The hydrogen sulfide content in the purified gas 03 is less than 2mg / m 3 , organic sulfur content is less than 12mg / m 3 The elemental sulfur generation rate is 97.8%.

[0083] Example 5

[0084] according to Figure 1 The device shown is used to remove hydrogen sulfide and organic sulfur from sulfur-containing gas.

[0085] The hydrogen sulfide content in the sulfur-containing gas is 5% (volume fraction) and the organic sulfur content is 200 mg / m 3 The concentration of alkali solution in the pneumatic emulsification absorption tower 11 is 20g / L, and a desulfurizing agent (composed of 80wt% triazine (amine-aldehyde condensation reaction product of 3-ethoxypropylamine and formaldehyde), 15wt% solvent (N-methylpyrrolidone) and 5wt% water) is sprayed into the gas-liquid separation tank 12; in the bioreactor 14, the desulfurizing bacteria community is a composite community of sulfur-excreting Thiobacillus and denitrifying Thiobacillus; in the low-temperature plasma treatment device 19, the discharge voltage is 350V, the discharge power is 500W, and the discharge time is 50min. The hydrogen sulfide content in the purified gas 03 is 0, and the organic sulfur content is less than 10mg / m 3 The elemental sulfur generation rate is 98.1%.

[0086] Example 6

[0087] according to Figure 1 The device shown is used to remove hydrogen sulfide and organic sulfur from sulfur-containing gas.

[0088] The hydrogen sulfide content in the sulfur-containing gas is 5% (volume fraction) and the organic sulfur content is 200 mg / m 3The concentration of alkali solution in the pneumatic emulsification absorption tower 11 is 20g / L, and a desulfurizer (composed of 80wt% triazine (amine-aldehyde condensation reaction product of N,N-dihydroxyethylaniline and formaldehyde), 15wt% solvent (N-methylpyrrolidone) and 5wt% water) is sprayed into the gas-liquid separation tank 12; in the bioreactor 14, the desulfurization bacteria community is a composite community of sulfur-excreting Thiobacillus and denitrifying Thiobacillus; in the low-temperature plasma treatment device 19, the discharge voltage is 350V, the discharge power is 500W, and the discharge time is 50min. The hydrogen sulfide content in the purified gas 03 is less than 2mg / m 3 , organic sulfur content is less than 6mg / m 3 The elemental sulfur generation rate is 97.1%.

[0089] Example 7

[0090] according to Figure 1 The device shown is used to remove hydrogen sulfide and organic sulfur from sulfur-containing gas.

[0091] The hydrogen sulfide content in the sulfur-containing gas is 12% (volume fraction) and the organic sulfur content is 400 mg / m 3 The concentration of alkali solution in the pneumatic emulsification absorption tower 11 is 25g / L, and it is sprayed into the gas-liquid separation tank 12 (the desulfurizer consists of 85wt% triazine (amine-aldehyde condensation reaction product of dimethylisopropanolamine and formaldehyde), 10wt% solvent (propylene glycol) and 5wt% water); in the bioreactor 14, the desulfurization bacteria are a composite bacteria of Thiobacillus excreta and Thiobacillus denitrificans; the discharge voltage in the low-temperature plasma treatment device 19 is 400V, the discharge power is 600W, and the discharge time is 50min. The hydrogen sulfide content in the purified gas 03 is less than 4mg / m 3 , organic sulfur content is less than 18mg / m 3 The elemental sulfur generation rate is 95.6%.

[0092] Example 8

[0093] according to Figure 1 The device shown is used to remove hydrogen sulfide and organic sulfur from sulfur-containing gas.

[0094] The hydrogen sulfide content in the sulfur-containing gas is 12% (volume fraction) and the organic sulfur content is 400 mg / m 3 The concentration of alkali solution in the pneumatic emulsification absorption tower 11 is 25g / L, and a desulfurizing agent (composed of 85wt% triazine (amine-aldehyde condensation reaction product of dimethylisopropanolamine and formaldehyde), 10wt% solvent (N-methylpyrrolidone) and 5wt% water) is sprayed into the gas-liquid separation tank 12; in the bioreactor 14, the desulfurizing bacteria community is a composite community of sulfur-excreting Thiobacillus and denitrifying Thiobacillus; in the low-temperature plasma treatment device 19, the discharge voltage is 400V, the discharge power is 600W, and the discharge time is 80min. The hydrogen sulfide content in the purified gas 03 is less than 3mg / m3 , organic sulfur content is less than 15mg / m 3 The elemental sulfur generation rate is 96.3%.

[0095] Comparative Example 1

[0096] The same method as in Example 4 is used, except that there is no triazine desulfurization agent fine desulfurization step. The hydrogen sulfide content in the purified gas 03 is 250 mg / m 3 , organic sulfur content is 150mg / m 3 The elemental sulfur generation rate is 94.5%.

[0097] Comparative Example 2

[0098] The same method as in Example 4 is used, except that there is no low-temperature plasma treatment step. The hydrogen sulfide content in the purified gas 03 is 30 mg / m 3 , organic sulfur content is 20mg / m 3 The elemental sulfur generation rate is 93.2%.

[0099] Comparative Example 3

[0100] The same method as in Example 4 is used, except that the pneumatic emulsification absorption tower is replaced by a common packed tower. The hydrogen sulfide content in the purified gas 03 is 150 mg / m 3 , organic sulfur content is 130mg / m 3 The elemental sulfur generation rate is 95.1%.

[0101] Comparative Example 4

[0102] The same method as in Example 4 is used, except that the discharge voltage in the low-temperature plasma treatment device 19 is 800 V, the discharge power is 1000 W, and the discharge time is 150 min. The hydrogen sulfide content in the purified gas 03 is 180 mg / m 3 , organic sulfur content is 50mg / m 3 The elemental sulfur generation rate is 91.4%.

[0103] Comparative Example 5

[0104] The same method as in Example 4 is used, except that the desulfurizing agent (40% by mass methyldiethanolamine solution) is sprayed into the gas-liquid separation tank 12. The hydrogen sulfide content in the purified gas 03 is 200 mg / m 3 , organic sulfur content is 160mg / m 3 The elemental sulfur generation rate is 94.2%.

[0105] Comparative Example 6

[0106] The same method as in Example 4 is used, except that the desulfurizer (the desulfurizer is composed of 60 wt% of triazine (amine-aldehyde condensation product of dimethyl isopropanolamine and formaldehyde), 20 wt% of solvent (N-methylpyrrolidone) and 20 wt% of water) is sprayed into the gas-liquid separation tank 12. The hydrogen sulfide content in the purified gas 03 is 120 mg / m 3 , organic sulfur content is 80mg / m 3 The elemental sulfur generation rate is 94.8%.

[0107] It can be seen from the data of Examples 1-8 and Comparative Examples 1-6 that the present invention integrates the combined process of alkali absorption-biological oxidation-triazine desulfurization agent fine desulfurization into the same system, adopts a pneumatic emulsification absorption tower to replace the traditional scrubbing tower, and selects a desulfurization agent of a specific composition. When used to treat high-sulfur gas, the purification capacity is high and hydrogen sulfide and organic sulfur in the sulfur-containing gas can be removed simultaneously, so that the H2S content in the purified gas is less than 4 mg / m 3 , organic sulfur content is less than 20mg / m 3 , and uses low-temperature plasma technology to stimulate the growth of desulfurization microorganisms and the accumulation of extracellular sulfur, thereby improving the efficiency of bioconversion / catalytic reactions, completely converting hydrogen sulfide in sulfur-containing gases into elemental sulfur, and increasing the yield of elemental sulfur, making the generation rate of elemental sulfur greater than 95%. However, in Comparative Example 1, triazine desulfurizer is not used for fine desulfurization treatment, resulting in ineffective removal of hydrogen sulfide and organic sulfur in the purified gas; in Comparative Example 2, low-temperature plasma treatment is not provided, resulting in low efficiency of biological transformation / catalytic reaction of desulfurization bacteria in the bioreactor, increased content of hydrogen sulfide and organic sulfur in the purified gas, and reduced generation rate of elemental sulfur; in Comparative Example 3, ordinary packed tower is used, and mass transfer efficiency is poor, resulting in reduced removal effect of hydrogen sulfide and organic sulfur in the purified gas; in Comparative Example 4, induction conditions in the low-temperature plasma treatment device are changed, resulting in low efficiency of biological transformation / catalytic reaction of desulfurization bacteria in the bioreactor, increased content of hydrogen sulfide and organic sulfur in the purified gas, and reduced generation rate of elemental sulfur; in Comparative Example 5, conventional desulfurizer is used, which has low sulfur capacity and is not equipped with regeneration device. If recycled, hydrogen sulfide and organic sulfur in the purified gas are not effectively removed; in Comparative Example 6, the composition of the desulfurizer is not within the scope of the present invention, and the desulfurization effect is poor, resulting in ineffective removal of hydrogen sulfide and organic sulfur in the purified gas.

[0108] In summary, the present invention uses a combined process of alkaline solution absorption-biological oxidation desulfurization-triazine desulfurization agent fine desulfurization to treat high-sulfur gas, has high purification capacity and can simultaneously remove hydrogen sulfide and organic sulfur in the sulfur-containing gas, so that the H2S content in the purified gas is less than 4 mg / m 3 , organic sulfur content is less than 20mg / m 3In addition, the present invention adopts a pneumatic emulsification absorption tower to replace the traditional scrubbing tower, and utilizes low-temperature plasma technology to stimulate the growth of desulfurization microorganisms and the accumulation of extracellular sulfur, which significantly improves the efficiency of biological conversion / catalytic reaction, completely converts hydrogen sulfide in sulfur-containing gas into elemental sulfur, increases the yield of elemental sulfur, maintains system stability, and enhances the desulfurization effect. The generation rate of elemental sulfur is greater than 95%.

[0109] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A device for removing hydrogen sulfide and organic sulfur from sulfur-containing gas, characterized in that: The device comprises a pneumatic emulsification absorption tower and a bioreactor; Wherein, a sprayer is arranged at the top of the pneumatic emulsification absorption tower for spraying alkali solution to convert hydrogen sulfide in the sulfur-containing gas into sulfide and obtain crude desulfurized gas; Wherein, the biological aerobic reactor is provided with a desulfurization bacteria group for converting sulfide into elemental sulfur; A gas-liquid separation tank is also arranged outside the pneumatic emulsification absorption tower, and an atomizing nozzle is arranged above the gas-liquid separation tank for spraying a desulfurizing agent to remove hydrogen sulfide and organic sulfur in the crude desulfurized gas.

2. The device according to claim 1, wherein: A low-temperature plasma treatment device is also arranged outside the biological aerobic reactor to induce the growth of sulfur oxidizing bacteria in the biological aerobic reactor.

3. The device according to claim 2, wherein: A solution pump is also provided between the biological aerobic reactor and the low-temperature plasma treatment device.

4. The device according to any one of claims 1 to 3, wherein: The device also includes a rich liquid pump, a settling tank, a centrifuge and a lean liquid pump; Preferably, the rich liquid pump is respectively connected to the discharge port of the pneumatic emulsification absorption tower and the water inlet of the biological aerobic reactor; the inlet of the sedimentation tank is connected to the overflow port of the biological aerobic reactor, and the discharge port of the sedimentation tank is connected to the centrifuge; the lean liquid pump is respectively connected to the outlet of the sedimentation tank and the upper end of the pneumatic emulsification absorption tower.

5. A method for removing hydrogen sulfide and organic sulfur from sulfur-containing gas, characterized in that: The method comprises subjecting the sulfur-containing gas to rough desulfurization treatment, biological oxidation treatment and fine desulfurization treatment in the device described in any one of claims 1 to 4.

6. The method according to claim 5, wherein: The method comprises the following steps: (1) subjecting the sulfur-containing gas to a rough desulfurization treatment in a pneumatic emulsification absorption tower included in the device to obtain a sulfide absorption rich liquid and a rough desulfurized gas; (2) subjecting the sulfide absorption rich liquid to biological oxidation treatment in a bioreactor included in the device to obtain elemental sulfur; (3) The crude desulfurized gas is subjected to fine desulfurization treatment in a gas-liquid separation tank included in the device to obtain purified gas.

7. The method according to claim 6, wherein: The method for rough desulfurization treatment comprises: using alkaline solution to convert hydrogen sulfide in the sulfur-containing gas into sulfide to obtain sulfide absorption rich liquid and rough desulfurized gas; Preferably, the alkali solution is an alkaline solution containing sodium; More preferably, the concentration of the alkali solution is 5-30 g / L and the pH value is 8-11; More preferably, the alkali solution is selected from at least one of Na2CO3, NaOH and NaHCO3.

8. The method according to claim 6, wherein: The biological oxidation treatment method comprises: using a desulfurization bacteria group to convert the sulfide in the sulfide absorption rich liquid into elemental sulfur; Preferably, the desulfurizing bacteria group is selected from at least one of Thiobacillus denitrificans, Thiobacillus thiosulfurans and Thiobacillus naples.

9. The method according to claim 6, wherein: The method further comprises using a low-temperature plasma treatment device included in the device to perform induction treatment on a portion of the desulfurization bacteria group in the bioreactor included in the device; Preferably, the conditions of the induction treatment include: a discharge voltage of 50V-500V, a discharge power of 30W-600W, and a discharge time of 5min-100min.

10. The method according to claim 6, wherein: The method for fine desulfurization treatment comprises: removing hydrogen sulfide and organic sulfur in the crude desulfurized gas by using a desulfurizer to obtain purified gas; Preferably, the desulfurizing agent consists of solvent A, solvent B and water; Preferably, based on the total mass of the desulfurizer, the content of the solvent A is 70wt%-90wt%, the content of the solvent B is 5wt%-20wt%, and the content of the water is 5wt%-10wt%; Preferably, the solvent A is selected from any one of the amine-aldehyde condensation reactants of dimethylisopropanolamine and formaldehyde, the amine-aldehyde condensation reactants of 3-ethoxypropylamine and formaldehyde, and the amine-aldehyde condensation reactants of N,N-dihydroxyethylaniline and formaldehyde; and the solvent B is selected from glycerol and / or N-methylpyrrolidone.

11. The method according to any one of claims 5 to 10, wherein: The sulfur-containing gas is selected from at least one of natural gas, oilfield associated gas, synthesis gas and biogas; Preferably, based on the volume of the sulfur-containing gas, the content of hydrogen sulfide in the sulfur-containing gas is 0.1 vol%-15 vol%, and the content of organic sulfur is 50-500 mg / m 3 .

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