A mobile bed activated carbon desulfurization and regeneration system
By using countercurrent moving bed desulfurization and cross-flow moving bed regeneration processes, the problem of limited sulfur capacity of fixed bed desulfurizing agents is solved, enabling continuous operation of gas desulfurization and regeneration. This is suitable for large-scale gas treatment and reduces equipment investment and operational complexity.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- CHINA ENERGY INVESTMENT CORP LTD
- Filing Date
- 2022-08-30
- Publication Date
- 2026-06-12
AI Technical Summary
In existing technologies, fixed-bed desulfurizing agents have limited sulfur capacity, requiring frequent regeneration, which leads to discontinuous operation, high equipment investment, and can only be used for small-scale gas desulfurization.
The process employs countercurrent moving bed desulfurization and cross-flow moving bed regeneration. The moving bed desulfurization and regeneration reaction devices are connected by a rotary airlock valve. The gas distribution cone and mesh structure are used to achieve uniform gas distribution and continuous operation of the desulfurizing agent. Combined with the adjustment of the material bed height and the detection and control of hydrogen sulfide to control the rotation speed of the rotary airlock valve, continuous desulfurization and regeneration of the gas are achieved.
It enables continuous operation of gas desulfurization and regeneration, reduces regeneration time, is suitable for large-scale gas desulfurization, and reduces equipment investment and operational complexity.
Smart Images
Figure CN117654261B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of chemical gas purification technology, and in particular to a reaction device for continuous desulfurization and regeneration using carbonaceous materials as the desulfurization medium. Background Technology
[0002] Sulfur-containing gases emitted during chemical processes need to be purified before they can be used or emitted again. Existing technologies for desulfurization and regeneration after desulfurization have been studied.
[0003] Patent CN1167813A describes an operation mode that uses a fixed-bed desulfurization and regeneration dual-bed switching. However, due to the limited sulfur capacity of activated carbon desulfurizer, it reaches saturation within several days or tens of days, requiring frequent regeneration and leading to problems such as discontinuous operation. To extend the regeneration cycle, a large amount of desulfurizer needs to be loaded, resulting in large equipment volume and high investment in both desulfurizer and equipment. As the flue gas volume increases, more equipment is added, and the operation and control system becomes increasingly complex.
[0004] While the radial cross-flow moving bed reactor (patent CN203694875U) offers advantages over fixed-bed reactors, such as stable continuous operation and reduced equipment investment and operating costs, and can be used for desulfurization of large volumes of gases with high hydrogen sulfide concentrations, a significant bed thickness is required to prevent the bottom of the desulfurizing agent bed from being penetrated due to near saturation. Consequently, the bed thickness at the bottom of the upper and lower sections is the same, resulting in a larger proportion of unused desulfurizing agent in the upper section and thus a relatively high amount of desulfurizing agent used. When used for large-scale gas desulfurization, the large amount of desulfurizing agent required necessitates a larger equipment size, thereby limiting the gas processing capacity.
[0005] The journal article "Rational Application of Activated Carbon Desulfurization Technology" (China Nitrogen Fertilizer, 1994, No. 5) generally points out that there are problems with frequent and long regeneration times of activated carbon. This is mainly due to the large height of the fixed bed, which leads to uneven resistance and flow deviation, resulting in incomplete regeneration. Reducing the bed height requires increasing the number of equipment units and increasing equipment investment. Summary of the Invention
[0006] To address the aforementioned technical problems in existing technologies, this invention employs a countercurrent moving bed desulfurization and cross-flow moving bed regeneration process, overcoming the limitations of traditional fixed bed desulfurization and regeneration processes, such as large activated carbon consumption, numerous equipment units, discontinuous operation, frequent switching, long regeneration time, and limitation to small-scale gas desulfurization.
[0007] To achieve the objectives of this invention, the following technical solution is adopted:
[0008] This invention provides a desulfurization and regeneration system for moving bed activated carbon. The desulfurization and regeneration system includes a moving bed desulfurization reactor and a moving bed regeneration reactor, which are connected by a rotary airlock valve.
[0009] The moving bed desulfurization reactor includes a desulfurization shell, a carbonaceous material inlet and a purified gas outlet located at the top of the desulfurization shell, and a raw material gas inlet and a saturated carbonaceous material outlet located at the bottom of the desulfurization shell. A gas distribution cone is provided at the bottom of the inner cavity of the desulfurization shell. The gas distribution cone includes an upwardly protruding conical gas distribution hood and an opening located at the lower edge of the conical gas distribution hood. The opening forms an annular channel with the bottom of the desulfurization shell, and the raw material gas inlet faces the interior of the conical gas distribution hood.
[0010] The moving bed regeneration reactor includes a regeneration shell, a hot regeneration gas inlet and a discharge port disposed on the regeneration shell. A saturated carbonaceous material inlet is provided at the top of the regeneration shell. Two layers of mesh are provided in the inner cavity of the regeneration shell to sequentially divide the inner cavity of the regeneration shell into a hot regeneration gas zone, a solid carbonaceous material zone and a cold regeneration gas zone. The hot regeneration gas inlet is located on one side of the hot regeneration gas zone in the regeneration shell. A regeneration carbon outlet is provided at the bottom of the solid carbonaceous material zone. A rotary airlock valve is provided on the regeneration carbon outlet. The discharge port is correspondingly located at the bottom of the cold regeneration gas zone.
[0011] In a specific embodiment of the desulfurization and regeneration system provided by this invention, a material layer height adjustment sleeve is provided at the carbonaceous material inlet. This material layer height adjustment sleeve includes an inner sleeve and an outer sleeve connected from the inside to the outside. Specifically, the inner sleeve and outer sleeve are a combination of two pipes with different diameters and lengths; the inner sleeve is shorter, and the outer sleeve is longer. The inner diameter of the outer sleeve is 2-4 mm larger than the outer diameter of the inner sleeve. The inner sleeve is fixed to the carbonaceous material inlet and serves as the feed pipe. An elongated groove is provided axially on the outer wall of the inner sleeve. A drilled screw hole is provided on the upper side wall of the outer sleeve, and a set screw is fixed in the drilled screw hole. The diameter of the set screw is slightly smaller than the width of the groove, so that the front end of the set screw can be engaged in the groove on the outer wall of the inner sleeve. By sliding the set screw within the groove, the outer sleeve can be moved axially. Tightening the set screw to press against the bottom of the groove fixes the outer sleeve at a certain height, preventing relative movement between the inner and outer sleeves. Due to the fluidity of solids, the height of the material layer inside the desulfurization reactor will not exceed the height of the lower outlet of the outer casing during operation.
[0012] In some specific embodiments, a material level detector is installed on the desulfurization shell to detect the height of the carbonaceous material (desulfurizing agent) layer in the inner cavity of the desulfurization shell. When the material level detected by the material level detector is lower than the lower outlet height of the outer sleeve of the material level adjustment sleeve, and there is a further decreasing trend, the operator can determine that the carbonaceous material (desulfurizing agent) feed pipe of the desulfurization reactor may be blocked, and then an adjustment plan can be made.
[0013] In a specific embodiment of the desulfurization and regeneration system provided by this invention, an upwardly protruding gas distribution cone is provided at the bottom of the inner cavity of the desulfurization shell. As is well known to those skilled in the art, the distribution cone is a common conical device used for material diversion. When the hot regeneration gas flow passes through the conical gas distribution hood, it can be evenly diverted and then enters the inner cavity of the desulfurization shell for desulfurization treatment. At the same time, the carbonaceous material (desulfurizing agent) layer in the inner cavity of the desulfurization shell will not fall downward through the conical gas distribution hood. In some specific embodiments, the upper cone angle of the conical gas distribution hood is 45° to 65°, for example, 50° or 60°.
[0014] In some specific desulfurization and regeneration systems, the saturated carbonaceous material outlet of the moving bed desulfurization reactor and the saturated carbonaceous material inlet of the moving bed regeneration reactor are respectively connected to the inlet and outlet of the rotary airlock valve.
[0015] In some specific desulfurization and regeneration systems of this invention, a hydrogen sulfide detector is installed at the purified gas outlet to detect the hydrogen sulfide content in the purified gas after desulfurization. Specifically, during the desulfurization process, the descending speed of the carbonaceous material layer in the desulfurization shell can be adjusted by controlling the rotation speed of the rotary airlock valve based on the H2S concentration displayed by the hydrogen sulfide detector at the purified gas outlet. For example, when the desulfurization process requires the H2S concentration in the outlet purified gas to be no greater than 5 ppm, if the hydrogen sulfide detector shows an H2S concentration greater than 5 ppm, the desulfurization effect can be improved by increasing the rotation speed of the rotary airlock valve; conversely, the rotation speed of the rotary airlock valve can be decreased.
[0016] In some specific desulfurization and regeneration systems, the lower part of the desulfurization shell is conical, specifically forming an "inverted cone" feeding hopper. A rotary airlock valve is fixed to the bottom of the "inverted cone" feeding hopper via a flange. The raw material gas inlet is located on the conical side wall of the desulfurization shell, and the raw material gas inlet introduces the raw material gas into the interior of the conical gas distribution hood through a pipeline. In some preferred embodiments, the conical gas distribution hood can be fixed to the inner wall of the desulfurization shell or the aforementioned pipeline.
[0017] In some specific desulfurization and regeneration systems, the saturated carbonaceous material (desulfurizing agent) after desulfurization falls into the solid carbonaceous material zone of the regeneration shell through a rotary airlock valve for regeneration. This solid carbonaceous material zone is formed by two layers of mesh. In some preferred embodiments, the mesh is made of austenitic stainless steel 304 or 304L, and the mesh aperture is 2-4 mm. The saturated carbonaceous material in this zone will not disperse into the hot regeneration gas zone and the cold regeneration gas zone.
[0018] In the moving bed regeneration reactor of the desulfurization and regeneration system provided by the present invention, the hot regeneration gas enters the hot regeneration gas zone through the hot regeneration gas inlet, and then enters the solid carbonaceous material zone through the screen to heat the saturated carbonaceous material (desulfurizing agent). The sulfur adsorbed in the saturated carbonaceous material becomes liquid, and then becomes gaseous and is separated from the saturated carbonaceous material. It then enters the cold regeneration gas zone to obtain sulfur and cold regeneration gas, and is discharged through the discharge port set at the bottom of the cold regeneration gas zone. The regenerated carbonaceous material is discharged from the regeneration carbon outlet at the bottom of the solid carbonaceous material zone.
[0019] In some specific embodiments, the temperature of the regeneration gas introduced through the thermal regeneration gas inlet is 350–450°C, the pressure is 0.01–0.05 MPa, and the gas space velocity is 300–500 h⁻¹. -1 .
[0020] The above technical solution achieves the following technical effects:
[0021] The desulfurization and regeneration system provided by this invention achieves continuous gas desulfurization and regeneration processes using a countercurrent moving bed reactor. The operation is simple and continuous, requiring no switching operations. Compared to using a fixed bed for desulfurizing agent regeneration, the desulfurization and regeneration system provided by this invention significantly shortens the regeneration time and is suitable for large-scale gas desulfurization and desulfurizing agent regeneration. Attached Figure Description
[0022] Figure 1 One embodiment of the desulfurization and regeneration system provided by the present invention;
[0023] Figure 2 : Figure 1 Cross-sectional view along the AA direction;
[0024] The components include: 1. Moving bed desulfurization reactor; 2. Moving bed regeneration reactor; 3. Purified gas outlet; 4. Material bed height adjustment sleeve; 5. Conical gas distribution hood; 6. Annular channel; 7. Raw material gas inlet; 8. Carbonaceous material inlet; 9. Rotary airlock valve one; 10. Saturated carbonaceous material inlet; 11. Hot regeneration gas inlet; 12. Partition screen; 13. Discharge port; 14. Hydrogen sulfide detector; 15. Regenerated carbon outlet; 16. Rotary airlock valve two; 17. Material level detector; and 18. Saturated carbonaceous material outlet. Detailed Implementation
[0025] To facilitate understanding of the present invention, the following description, in conjunction with embodiments, will further illustrate the invention. It should be understood that the following embodiments are merely for a better understanding of the invention and do not imply that the invention is limited to these embodiments.
[0026] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.
[0027] This invention provides a desulfurization and regeneration system for moving bed activated carbon, such as... Figure 1 As shown, the desulfurization and regeneration system includes a moving bed desulfurization reactor 1 and a moving bed regeneration reactor 2, which are connected by a rotary airlock valve 9. The moving bed desulfurization reactor 1 includes a desulfurization shell, a carbonaceous material inlet 8 and a purified gas outlet 3 located at the top of the desulfurization shell, and a raw material gas inlet 7 and a saturated carbonaceous material outlet 18 located at the bottom of the desulfurization shell.
[0028] A gas distribution cone is provided at the bottom of the inner cavity of the desulfurization shell. The gas distribution cone includes an upwardly protruding conical gas distribution hood 5 and an opening located at the lower edge of the conical gas distribution hood 5, such as... Figure 2 As shown, the lower edge opening of the gas distribution cone forms an annular channel 6 with the bottom of the desulfurization shell, allowing the saturated desulfurizing agent formed after desulfurization to fall from the annular channel 6 to the carbonaceous material outlet 18. The raw material gas entering from the raw material gas inlet 7 is transported to the interior of the conical gas distribution hood 5 through a pipeline.
[0029] The moving bed regeneration reactor 2 includes a regeneration shell, a hot regeneration gas inlet 11 and a discharge port 13 disposed on the regeneration shell, a saturated carbonaceous material inlet 10 at the top of the regeneration shell, and two layers of mesh 12 disposed in the inner cavity of the regeneration shell to sequentially divide the inner cavity of the regeneration shell into a hot regeneration gas zone, a solid carbonaceous material zone and a cold regeneration gas zone. The hot regeneration gas inlet 11 is disposed on one side of the hot regeneration gas zone, and the discharge port 13 is correspondingly disposed at the bottom of the cold regeneration gas zone. A regeneration carbon outlet 15 is correspondingly disposed at the bottom of the solid carbonaceous material zone, and a rotary airlock valve 16 is disposed on the regeneration carbon outlet 15.
[0030] In the desulfurization and regeneration system provided by the present invention, a material layer height adjustment sleeve 4 is provided at the carbon material inlet 8; specifically, the material layer height adjustment sleeve 4 includes an inner sleeve and an outer sleeve that are sequentially sleeved from the inside to the outside. The inner sleeve is fixed on the carbon material inlet 8, and an elongated groove is provided on the outer wall of the inner sleeve in the axial direction. A drilled screw hole is provided on the upper side wall of the outer sleeve, and a set screw is fixed in the drilled screw hole. The diameter of the set screw is slightly smaller than the width of the groove so that the front end of the set screw can be stuck in the groove on the outer wall of the inner sleeve. By sliding the set screw in the groove, the outer sleeve can be moved axially.
[0031] In the desulfurization and regeneration system provided by the present invention, a material level detector 17 is provided on the top of the desulfurization shell to detect the material layer height of the desulfurizing agent in the inner cavity of the desulfurization shell.
[0032] In some specific embodiments, the upper cone angle of the conical gas distribution hood 5 in the gas distribution cone inside the desulfurization shell is 45° to 65°, so that the raw gas entering from the raw gas inlet 7 can be evenly distributed at the upwardly convex gas distribution cone before entering the desulfurization shell for desulfurization treatment.
[0033] In some specific embodiments, a hydrogen sulfide detector 14 is installed on the purified gas outlet 3 to detect the hydrogen sulfide content in the purified gas after desulfurization. Specifically, during the desulfurization process, the descending speed of the carbonaceous material layer in the desulfurization shell can be adjusted by controlling the rotational speed of the rotary airlock valve 9 based on the H2S concentration displayed by the hydrogen sulfide detector 14 on the purified gas outlet 3.
[0034] In some specific embodiments, the lower part of the desulfurization shell of the present invention is conical, and the raw material gas inlet 7 is opened on the conical sidewall of the desulfurization shell; in some preferred embodiments, the raw material gas inlet 7 introduces the raw material gas into the interior of the conical gas distribution hood 5 through a pipeline, so as to distribute the raw material gas more evenly.
[0035] The saturated carbonaceous material outlet 18 of the moving bed desulfurization reactor 1 and the saturated carbonaceous material inlet 10 of the moving bed regeneration reactor 2 are respectively connected to the inlet and outlet of the rotary airlock valve 9.
[0036] In some specific desulfurization and regeneration systems, the saturated carbonaceous material (desulfurizing agent) after desulfurization falls into the solid carbonaceous material zone of the regeneration shell through the rotary airlock valve 9 for regeneration. This solid carbonaceous material zone is formed by two layers of mesh 12 on the left and right sides. The saturated carbonaceous material particles entering through the saturated carbonaceous material inlet 10 are regenerated in the solid carbonaceous material zone. In some preferred embodiments, the material of the mesh 12 can be selected from austenitic stainless steel 304 or 304L, and the aperture of the mesh 12 is 2-4 mm.
[0037] In some specific embodiments, the temperature of the regeneration gas introduced through the thermal regeneration gas inlet 11 is 350–450°C, the pressure is 0.01–0.05 MPa, and the gas space velocity is 300–500 h⁻¹. -1 .
[0038] During the continuous desulfurization and regeneration of the desulfurization medium (carbonaceous material) using the desulfurization and regeneration system provided by this invention, fresh or regenerated solid carbonaceous material is added from the carbonaceous material inlet 8 at the top of the moving bed desulfurization reactor 1 and enters the inner cavity of the desulfurization shell. Raw material gas with a certain amount of oxygen (oxygen-sulfur ratio of 1.5-2) is added in advance and enters from the raw material gas inlet 7. After passing through the gas distribution cone, it comes into countercurrent contact with the carbonaceous material from bottom to top. H2S and O2 undergo a desulfurization reaction in the carbonaceous material to generate sulfur. The desulfurized gas is discharged from the system from the purified gas outlet 3 at the top of the moving bed desulfurization reactor 1.
[0039] The descending speed of the carbonaceous material in the moving bed desulfurization reactor 1 is controlled according to the H2S concentration displayed by the hydrogen sulfide detector 14 at the purified gas outlet 3. Specifically, this is achieved by controlling the rotation speed of the rotary airlock valve 9 connected to the carbonaceous material outlet. In some specific embodiments, if the desulfurization treatment requires the H2S concentration in the purified gas outlet to be no greater than 5 ppm, when the hydrogen sulfide detector shows that the H2S concentration in the outlet gas is greater than 5 ppm, the desulfurization effect can be improved by increasing the rotation speed of the rotary airlock valve 9; conversely, the rotation speed of the rotary airlock valve 9 can be decreased.
[0040] The saturated carbonaceous material after desulfurization treatment enters the solid carbonaceous material zone through the saturated carbonaceous material inlet 10 of the moving bed regeneration reactor 2, with hot regeneration gas (temperature 350-450℃, pressure 0.01-0.05MPa, gas space velocity 300-500h⁻¹). -1The gas enters through the hot regeneration gas inlet 11, passes through the partition 12, and enters the saturated carbonaceous material in the solid carbonaceous material zone to heat up the temperature. The sulfur adsorbed in the saturated carbonaceous material becomes liquid, and then becomes gaseous and is separated from the saturated carbonaceous material. The cooled regeneration gas then passes through the other side partition 12 and is discharged from the discharge port 13 at the bottom of the cold regeneration gas zone. The regenerated carbonaceous material in the solid carbonaceous material zone is discharged from the regenerated carbon outlet 15 located at the bottom of the solid carbonaceous material zone.
Claims
1. A desulfurization and regeneration system for moving bed activated carbon, characterized in that, The desulfurization and regeneration system includes a moving bed desulfurization reactor and a moving bed regeneration reactor, which are connected by a rotary airlock valve. The moving bed desulfurization reactor includes a desulfurization shell, a carbonaceous material inlet and a purified gas outlet located at the top of the desulfurization shell, and a raw material gas inlet and a saturated carbonaceous material outlet located at the bottom of the desulfurization shell. A gas distribution cone is provided at the bottom of the inner cavity of the desulfurization shell. The gas distribution cone includes an upwardly protruding conical gas distribution hood and an opening located at the lower edge of the conical gas distribution hood. The opening forms an annular channel with the bottom of the desulfurization shell, and the raw material gas inlet faces the interior of the conical gas distribution hood. The moving bed regeneration reactor includes a regeneration shell, a hot regeneration gas inlet and a discharge port disposed on the regeneration shell, a saturated carbonaceous material inlet at the top of the regeneration shell, and two layers of mesh in the inner cavity of the regeneration shell to sequentially divide the inner cavity of the regeneration shell into a hot regeneration gas zone, a solid carbonaceous material zone and a cold regeneration gas zone. The hot regeneration gas inlet is located on one side of the hot regeneration gas zone in the regeneration shell, and a regeneration carbon outlet is provided at the bottom of the solid carbonaceous material zone. A rotary airlock valve is provided on the regeneration carbon outlet, and the discharge port is correspondingly located at the bottom of the cold regeneration gas zone. The carbonaceous material inlet is equipped with a material layer height adjustment sleeve. The material layer height adjustment sleeve includes an inner sleeve and an outer sleeve connected from the inside to the outside. The inner sleeve is fixed to the carbonaceous material inlet, and the outer wall of the inner sleeve has an elongated groove along its axial direction. A drilled screw hole is opened on the upper side wall of the outer sleeve, and a set screw is fixed in the drilled screw hole. The front end of the set screw is engaged in the groove so that the outer sleeve is movably connected to the inner sleeve.
2. The desulfurization and regeneration system according to claim 1, characterized in that, The desulfurization shell is equipped with a material level detector to detect the height of the desulfurizing agent layer in the inner cavity of the desulfurization shell.
3. The desulfurization and regeneration system according to claim 2, characterized in that, The upper cone angle of the conical gas distribution hood in the gas distribution cone is 45°~65°.
4. The desulfurization and regeneration system according to any one of claims 1 to 3, characterized in that, A hydrogen sulfide detector is installed at the purified gas outlet to detect the hydrogen sulfide content in the purified gas at the outlet.
5. The desulfurization and regeneration system according to any one of claims 1 to 3, characterized in that, The lower part of the desulfurization shell is conical, and the raw gas inlet is located on the conical sidewall of the desulfurization shell.
6. The desulfurization and regeneration system according to claim 5, characterized in that, The raw material gas inlet introduces the raw material gas into the interior of the conical gas distribution hood through a pipeline.
7. The desulfurization and regeneration system according to any one of claims 1 to 3 and 6, characterized in that, The saturated carbonaceous material outlet of the moving bed desulfurization reactor and the saturated carbonaceous material inlet of the moving bed regeneration reactor are respectively connected to the inlet and outlet of the rotary airlock valve.
8. The desulfurization and regeneration system according to any one of claims 1 to 3 and 6, characterized in that, The material of the mesh in the inner cavity of the recycled shell is selected from austenitic stainless steel 304 or 304L, and the mesh has a pore size of 2 to 4 mm.
9. The desulfurization and regeneration system according to claim 8, characterized in that, The regeneration gas introduced through the thermal regeneration gas inlet has a temperature of 350~450℃, a pressure of 0.01~0.05 MPa, and a gas space velocity of 300~500 h⁻¹. -1 .