CN203663682U - Device for absorbing and removing sulfur dioxide in CLAUS tail gas with ammonium sulfite absorption method - Google Patents

Abstract

The utility model discloses a device for CLAUS tail gas desulfurization based on an ammonium sulfite absorption method, which is characterized in that the device is a three-layer tower structure, which is respectively a countercurrent spray absorption area, a bubbling absorption area and a circulation concentration area, The upper part is provided with a gas outlet, and the interior of the device is arranged in order from top to bottom: a mist eliminator, which is arranged below the gas outlet; a spray absorption area, which is arranged under the mist eliminator, and is mainly composed of three layers of spray devices; The bubbling absorption zone is set under the countercurrent spraying absorption zone to absorb the tail gas for the first time; the gas distributor is set under the bubbling absorption zone; the concentration circulation zone is set at the bottom of the device. The device for CLAUS tail gas desulfurization based on the amino method of the utility model can not only absorb _SO2 gas efficiently, but also effectively solve the shortcomings of ammonia escape and large liquid-gas ratio.

Description

Ammonium sulfite absorption method CLAUS tail gas absorption desulfurization device

technical field

The utility model relates to a device for CLAUS tail gas desulfurization based on an ammonium sulfite absorption method.

Background technique

At present, the industrial treatment of sulfur-containing gases in Claus tail gas is mainly based on H2S selective oxidation technology, and on the basis of this technology, a variety of process technologies such as Superclaus process, Euroclaus process, and BSR/Hi-Activity process have been developed. However, this technology is mainly limited by the activity and selectivity of the catalyst, and the currently widely used catalyst systems (carbon system, metal oxide system) all have certain defects and limitations, such as the production of toxic by-products and easy deactivation.

In order to solve the problem that the selective oxidation of H ₂ S is limited by the activity of the catalyst, the ammonium sulfite absorption sulfur recovery technology is applied to the sulfur recovery process of the Claus tail gas. After the Claus tail gas is oxidized to SO ₂ , the sulfur recycling. Ammonium sulfite absorption sulfur recovery technology uses (NH ₄ ) ₂ SO ₃ as the main absorbent, which can effectively absorb and remove SO ₂ , and the absorbent can be recycled. This technology does not produce any waste water, waste liquid and waste residue , and thus received extensive attention. Ammonia absorption device is the core of ammonium sulfite absorption recovery technology. At present, industrial ammonia absorption and desulfurization devices are mainly spray towers, but there are problems such as low desulfurization efficiency, high energy consumption, and serious ammonia escape due to large liquid-gas ratio. further application of the law. The present invention is improved and innovated on the basis of the traditional ammonia absorption device, which not only greatly improves the absorption and recovery efficiency of SO ₂ but also effectively solves the shortcomings of ammonia escape and large liquid-gas ratio. The enriched NH ₄ HSO ₃ absorption liquid not only It can be further oxidized and crystallized to produce (NH ₄ ) ₂ SO ₄ fertilizer, and the absorption liquid can also be sprayed back into the Claus combustion furnace to participate in the Claus reaction to produce sulfur, so it has a good application prospect in industrial applications.

Contents of the invention

The purpose of this utility model is to provide a novel ammonium sulfite absorption method CLAUS tail gas absorption and desulfurization device, and apply the device to the sulfur recovery process of Claus tail gas in coal chemical industry and petrochemical acid gas.

The ammonium sulfite absorption method CLAUS tail gas absorption and desulfurization device provided by the utility model is characterized in that the device is a three-layer tower structure, which is respectively a countercurrent spray absorption area, a bubbling absorption area and a circulation concentration area, and the upper part is provided with a gas outlet. The interior of the device is arranged in order from top to bottom: the demister, which is set under the gas outlet; the spray absorption area, which is set under the demister, and is mainly composed of three layers of spray devices; the bubbling absorption area, which is set Under the countercurrent spray absorption area, the exhaust gas is first absorbed; the gas distributor is arranged under the bubbling reaction area; the concentration absorption area is arranged at the bottom of the device.

The utility model of the ammonium sulfite absorption method CLAUS tail gas absorption desulfurization device is further characterized in that the gas inlet is connected to a gas distributor, and the gas distributor is arranged between the bubbling absorption area and the concentration circulation area.

The utility model of ammonium sulfite absorption method CLAUS tail gas absorption desulfurization device is further characterized in that the device is provided with a bubbling absorption area, and an ammonia water inlet and an absorption liquid overflow are arranged in the bubbling absorption area.

The ammonium sulfite absorption method CLAUS tail gas absorption desulfurization device of the utility model is further characterized in that the device is provided with a concentration circulation area, and the concentration circulation area is provided with an ammonia water inlet, a concentration outlet and a circulation liquid outlet.

The utility model has the following beneficial effects:

1) The ammonium sulfite absorption method CLAUS tail gas absorption and desulfurization device can greatly improve the absorption and recovery efficiency of SO ₂ and effectively solve the shortcomings of ammonia escape and large liquid-gas ratio.

2) Ammonium sulfite absorption method The NH ₄ HSO ₃ absorption liquid enriched by the CLAUS tail gas absorption desulfurization device can not only be further oxidized and crystallized to produce (NH ₄ ) ₂ SO ₄ fertilizer, but also can be sprayed back into the Claus combustion furnace to participate in Claus reaction produces sulfur, which has a good application prospect

Description of drawings

Fig. 1 is a structural schematic diagram of the ammonium sulfite absorption method CLAUS tail gas absorption desulfurization device of the present invention. The number labels in the figure are as follows:

1. Claus tail gas inlet 2. Gas distributor 3. Ammonia water inlet 4. Acidity meter 5. Bubble absorption area 6. Countercurrent spray absorption area 7. Spray layer 8. Demister 9. Ammonia water inlet 10. Circulation concentration area 11. Acidity meter 12. Purified gas outlet 13. Circulating spray liquid 14. Spray liquid circulation pump 15. Absorbing liquid in bubbling area 16. Absorbing liquid in bubbling area 17. Concentrated liquid outlet

Detailed ways

The specific working method of the ammonium sulfite absorption method CLAUS tail gas absorption desulfurization device of the present utility model is as follows:

After the Claus tail gas that has been completely oxidized to SO ₂ enters the absorption device through the gas inlet 1, the gas is firstly distributed evenly by the gas distributor 2 and passed through the bubbling absorption zone 5, which not only carries out the second SO ₂ gas Absorb once, and play the role of lowering the gas temperature and dust removal. The pH value of the absorption liquid in the bubbling absorption area is measured by the acidity meter 4 in the absorption area. The pH value of the absorption liquid is controlled by ammonia water through the ammonia water inlet 3 at 5- Within the range of 7, the volume of the bubbling absorption zone is controlled by the overflow port. As the absorption reaction proceeds, the excess absorption liquid 16 generated by the absorption reaction enters the circulation concentration zone through the overflow port to ensure that the volume of the bubbling absorption zone is constant . The absorbent outlet 15 is opened when the bubble zone is evacuated. The gas passing through the bubbling absorption area enters the countercurrent spray absorption area 6, and the spray liquid is sprayed out from the spray layer installed on the upper part of the countercurrent spray absorption area to contact the gas in a countercurrent manner, and the second absorption reaction of _SO2 gas is carried out , the absorption liquid passes through the concentrated circulation area and is recycled for absorption and utilization. Finally, the gas passes through the mist eliminator 8 to effectively capture escaped ammonia and colloidal particles, and then is discharged through the purified gas outlet 12. The absorption liquid enriched in the bubbling absorption zone and the countercurrent spraying absorption zone enters the concentrated circulation zone 10, and in the concentrated circulation zone, the enriched absorption liquid is regenerated by supplementing ammonia water through the ammonia water inlet 9 to ensure that the pH value of the absorption liquid is between 5- 7 range, the pH of the absorption liquid is measured by the acidity meter 11 located in the concentrated circulation area, and the regenerated absorption liquid enters the spray layer through the circulation pump 14 for circulation absorption. The volume of the absorption liquid in the entire concentrated circulation area is kept constant by the liquid level switch, and the enriched absorption liquid is discharged through the absorption liquid outlet 17, and the enriched absorption liquid that is discharged can be produced through oxidation crystallization and other processes to produce ammonium sulfate fertilizer, and can also be returned to Claus The reaction furnace participates in the Claus reaction to produce sulfur.

The ammonium sulfite absorption method CLAUS tail gas absorption and desulfurization device of the utility model not only greatly improves the absorption and recovery efficiency of SO2 but also effectively solves the shortcomings of ammonia escape and large liquid-gas ratio. The main chemical reactions that take place during the absorption process are as follows:

2NH ₃ +SO ₂ +H ₂ O→(NH ₄ ) ₂ SO ₃ (absorbent)

(NH ₄ ) ₂ SO ₃ +SO ₂ +H ₂ O→2NH ₄ HSO ₃

NH ₄ HSO ₃ +NH ₃ →(NH ₄ ) ₂ SO ₃

Claims (4)

1. the device for the desulfurization of CLAUS tail gas based on ammonium sulfite absorption process, is characterized in, device is three layers of tower structure, is respectively countercurrent spray uptake zone, bubble absorption district and circulation enrichment region.

2. the device of ammonium sulfite absorption process CLAUS tail gas according to claim 1 desulfurization, is characterized in that, device is provided with bubble absorption district, is provided with ammoniacal liquor import and absorption liquid overfall in bubble absorption district.

3. the device of ammonium sulfite absorption process CLAUS tail gas according to claim 1 desulfurization, is characterized in that, device is provided with concentrated race way, in concentrated race way, is provided with ammoniacal liquor import, concentrated outlet and circulation fluid outlet.

4. the device of ammonium sulfite absorption process CLAUS tail gas according to claim 1 desulfurization, is characterized in that, gas inlet is connecting gas distributor, and gas distributor is arranged between bubble absorption district and concentrated race way.

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