Integrated flue gas purification tower

Abstract

The invention discloses an integrated flue gas purification tower, the integrated flue gas purification tower comprises an air cooling tower, a pre-washing tower and an absorption tower, the air cooling tower is provided with a flue gas channel, the pre-washing tower is located in the air cooling tower, the pre-washing tower is communicated with the flue gas channel, the pre-washing tower comprises a purification section and a cooling section which are arranged from bottom to top, the air cooling tower is located in the air cooling tower, the absorption tower is communicated with the pre-washing tower, and the absorption tower comprises an absorption section and a washing section which are arranged from bottom to top, so that the flue gas passing through the pre-washing tower sequentially enters the absorption section and the washing section to be subjected to carbon capture and washing. According to the integrated flue gas purification tower disclosed by the invention, the tower devices for desulfurization, denitrification and carbon capture and related auxiliary equipment are integrated in the air cooling tower, so that the internal space of the air cooling tower is reasonably utilized, the overall occupied area is reduced, the flue gas flow is shortened, and the flue gas purification treatment efficiency is improved.

Description

Technical Field

[0001] The invention relates to the technical field of flue gas treatment, and in particular to an integrated flue gas purification tower. Background Art

[0002] A carbon capture power plant is a power plant that uses carbon capture technology to capture and separate carbon dioxide from flue gas to reduce greenhouse gas emissions. The process flow required for flue gas emissions from a carbon capture power plant mainly includes flue gas pretreatment and carbon dioxide capture. Flue gas pretreatment is to remove harmful components such as particulate matter, sulfides and nitrogen oxides in the flue gas to ensure the normal operation of the carbon capture equipment and extend its service life. A portion of the pretreated flue gas is extracted for carbon dioxide capture to reduce the greenhouse gas content in the flue gas emitted by the power plant so that it meets the emission standards.

[0003] However, the flue gas treatment process in the related art is complicated, involves numerous towers, and has the problems of large system footprint, high economic cost and low treatment efficiency. Summary of the invention

[0004] The present invention is based on the inventor's discovery and understanding of the following facts and problems:

[0005] In the related technology, the flue gas discharged from the boiler needs to be desulfurized and denitrated by the denitrification tower and the desulfurization tower. The flue gas after desulfurization and denitrification is washed and cooled by the pre-washing tower, and then transported to the absorption tower for carbon dioxide capture, and finally discharged through the chimney. In addition, the cooling water required by each tower needs to be provided by a cooling water tower.

[0006] Therefore, the flue gas treatment process requires a large number of towers, each of which is set up separately, resulting in a large footprint for the entire system and high economic costs. The towers need to be transported through pipelines, and the flow of flue gas and liquid is long, resulting in reduced flue gas treatment efficiency and high energy consumption.

[0007] The present invention aims to solve one of the technical problems in the related art at least to a certain extent.

[0008] To this end, an embodiment of the present invention proposes an integrated flue gas purification tower to reduce floor space and improve flue gas treatment efficiency.

[0009] The integrated flue gas purification tower of the embodiment of the present invention comprises:

[0010] An air cooling tower, wherein the bottom wall of the air cooling tower is provided with a plurality of air inlet channels, the air cooling tower is provided with a plurality of conical radiator groups, the plurality of air inlet channels correspond to and are connected with the plurality of radiator groups one by one, the radiator groups extend in a vertical direction, and the air cooling tower is provided with a flue gas channel;

[0011] A pre-washing tower, the pre-washing tower is located inside the air-cooling tower, the pre-washing tower is connected to the radiator group to provide cooling to the pre-washing tower, the pre-washing tower is connected to the flue gas channel, and the pre-washing tower includes a purification section and a cooling section arranged from bottom to top, so that the flue gas enters the purification section and the cooling section in sequence for desulfurization, denitrification and cooling;

[0012] An absorption tower, wherein the absorption tower is located inside the air-cooled tower, the absorption tower is connected to the radiator group to provide cooling to the absorption tower, the absorption tower is connected to the pre-washing tower, and the absorption tower includes an absorption section and a washing section arranged from bottom to top, so that the flue gas passing through the pre-washing tower enters the absorption section and the washing section in turn for carbon capture and washing.

[0013] In some embodiments, the integrated flue gas purification tower also includes a chimney, which is arranged at the top of the absorption tower, and the pre-wash tower and the absorption tower are respectively connected to the chimney so that the flue gas passing through the pre-wash tower and / or the absorption tower is discharged through the chimney.

[0014] In some embodiments, a booster fan is provided between the pre-wash tower and the absorption tower, and the booster fan is used to pressurize the flue gas flowing from the pre-wash tower to the absorption tower.

[0015] In some embodiments, the integrated flue gas purification tower also includes a solution tank group, which is located in the air-cooled tower. The solution tank group includes a first storage tank, a second storage tank and a third storage tank. The first storage tank is connected to the purification section to transport purification liquid to the purification section, the second storage tank is connected to the absorption section to transport absorption liquid to the absorption section, and the third storage tank is connected to the cooling section and the washing section to transport spray liquid to the cooling section and the washing section.

[0016] In some embodiments, the purification liquid uses sulfite, thiosulfate and alkali solution or alkali solution mixed with carbonate as reaction raw materials to react with flue gas.

[0017] In some embodiments, the absorption liquid uses an organic amine solution as a reaction raw material to react with the flue gas.

[0018] In some embodiments, the integrated flue gas purification tower also includes a water-cooled heat exchanger unit, which is located in the air-cooled tower. The water-cooled heat exchanger unit is connected to the radiator group, the pre-wash tower and the absorption tower to utilize the cooling water naturally air-cooled by the radiator group to cool the purified liquid, the absorption liquid and the spray liquid.

[0019] In some embodiments, the cooling section is connected to the washing section so that the spray liquid in the washing section can be replenished into the cooling section.

[0020] In some embodiments, the integrated flue gas purification tower also includes a circulating pump unit, which is located in the air-cooled tower. The circulating pump unit is connected to the radiator group, the pre-wash tower, the absorption tower, the solution tank group and the water-cooled heat exchanger unit, and the circulating pump unit is used to drive the liquid flow.

[0021] In some embodiments, the integrated flue gas purification tower also includes a waste liquid pool, which is located in the air-cooled tower and connected to the pre-wash tower and the absorption tower. The waste liquid pool is used to discharge the waste liquid generated by the pre-wash tower and the absorption tower.

[0022] In summary, the integrated flue gas purification tower of the embodiment of the present invention adopts an air-cooled tower as the circulating cooling water supply equipment of the power plant, integrates the desulfurization, denitrification, carbon capture towers and related auxiliary equipment in the air-cooled tower, rationally utilizes the internal space of the air-cooled tower, and reduces the overall footprint.

[0023] In addition, only two towers, the pre-washing tower and the absorption tower, are needed to purify the flue gas, which shortens the flow of the flue gas. The air-cooled tower is set around the pre-washing tower and the absorption tower, which also shortens the flow of cooling water. It not only improves the efficiency of the flue gas purification treatment, but also further reduces the overall footprint by shortening the distance of the pipeline. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 Schematic diagram of an integrated flue gas purification tower according to an embodiment of the present invention.

[0025] Figure 2 Schematic diagram of a carbon capture system according to an embodiment of the present invention.

[0026] Reference numerals:

[0027] 1-air cooling tower, 101-radiator group, 102-flue gas channel, 2-pre-washing tower, 201-purification section, 202-cooling section, 3-absorption tower, 301-absorption section, 302-washing section, 4-chimney, 5-booster fan, 6-solution tank group, 7-water-cooled heat exchange unit, 8-circulation pump unit, 9-waste liquid pool. DETAILED DESCRIPTION

[0028] Embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0029] The integrated flue gas purification tower according to an embodiment of the present invention will be described below with reference to the accompanying drawings.

[0030] like Figure 1As shown, the integrated flue gas purification tower of the embodiment of the present invention includes: an air cooling tower 1, a pre-washing tower 2 and an absorption tower 3.

[0031] There are multiple air inlet channels on the peripheral wall at the bottom of the air cooling tower 1. Multiple conical radiator groups 101 are arranged in the air cooling tower 1. The multiple air inlet channels correspond to and are connected to the multiple radiator groups 101 one by one. The radiator groups 101 extend in the vertical direction. Natural wind flows from the four sides of the air cooling tower 1 through the air inlet channels into the conical space of the radiator group 101. The upward flowing wind dissipates the heat and cools the water in the water pipes of the radiator group 101 naturally.

[0032] The air-cooling tower 1 is provided with a flue gas channel 102, and the pre-washing tower 2 and the absorption tower 3 are both located inside the air-cooling tower 1. The internal space of the air-cooling tower 1 is rationally utilized to achieve multi-tower integration and reduce the overall floor space.

[0033] The pre-wash tower 2 is connected to the flue gas channel 102, and the pre-wash tower 2 includes a purification section 201 and a cooling section 202 arranged from bottom to top. The flue gas flows into the purification section 201 for desulfurization and denitrification, and then enters the cooling section 202 to be cooled to a preset temperature for subsequent carbon capture process. Compared with the flue gas pretreatment in the related art, it is necessary to set up three towers, namely a denitrification tower, a desulfurization tower and a cooling tower. The integrated flue gas purification tower of the embodiment of the present invention only needs a pre-wash tower 2 to achieve flue gas desulfurization, denitrification and cooling, shortening the flow path of the flue gas, reducing the risk of leakage and escape of the flue gas, shortening the length of the flue gas transmission pipeline, and further reducing the floor space.

[0034] The absorption tower 3 is connected to the pre-wash tower 2, and the absorption tower 3 includes an absorption section 301 and a washing section 302 arranged from bottom to top. The flue gas from the pre-wash tower 2 flows to the absorption section 301 of the absorption tower 3 for carbon dioxide capture, and then flows into the washing section 302 for washing before being discharged.

[0035] The pre-wash tower 2 and the absorption tower 3 are respectively connected to the radiator group 101 to provide the cooling water for natural heat dissipation to the pre-wash tower 2 and the absorption tower 3. Compared with the related art, the cooling water tower is set separately and the cooling water needs to be transported through a long-distance pipeline. The integrated flue gas purification tower of the embodiment of the present invention arranges the air-cooled tower 1 around the pre-wash tower 2 and the absorption tower 3, shortening the flow path of the cooling water, shortening the length of the delivery pipeline, and further reducing the occupied area.

[0036] Therefore, the efficiency of flue gas purification treatment is improved by shortening the process of flue gas and liquid.

[0037] like Figure 1 As shown, the integrated flue gas purification tower of the embodiment of the present invention also includes a chimney 4, which is arranged at the top of the absorption tower 3, and the pre-washing tower 2 and the absorption tower 3 are respectively connected to the chimney 4, so that the flue gas passing through the pre-washing tower 2 and / or the absorption tower 3 is discharged through the chimney 4.

[0038] It is understandable that a portion of the flue gas after desulfurization and denitrification is extracted and transported to the absorption tower 3 for carbon capture process to ensure that the carbon dioxide content in the flue gas emitted by the power plant as a whole is lower than the emission standard, and there is no need to capture all of it.

[0039] Therefore, the pre-wash tower 2 is directly connected to the chimney 4 to discharge a part of the flue gas after desulfurization and denitrification, and the other part is discharged through the chimney 4 after carbon dioxide is captured by the absorption tower 3.

[0040] Furthermore, if Figure 1 As shown, a booster fan 5 is provided between the pre-wash tower 2 and the absorption tower 3, and the booster fan 5 is used to pressurize the flue gas flowing from the pre-wash tower 2 to the absorption tower 3, so as to improve the effect of flue gas carbon capture.

[0041] like Figure 1 As shown, the integrated flue gas purification tower of the embodiment of the present invention further includes a solution tank group 6, and the solution tank group 6 is located in the air-cooled tower 1. The solution tank group 6 includes a first storage tank, a second storage tank and a third storage tank, and the first storage tank is connected to the purification section 201 to transport the purification liquid to the purification section 201. The second storage tank is connected to the absorption section 301 to transport the absorption liquid to the absorption section 301. The third storage tank is connected to the cooling section 202 and the washing section 302 to transport the spray liquid to the cooling section 202 and the washing section 302.

[0042] It can be understood that the purification section 201 at the lower part of the pre-wash tower 2 washes the flue gas with the purification liquid delivered by the first storage tank to remove NO in the flue gas. x and SO x Optionally, the purification liquid uses sulfite, thiosulfate and alkali solution or alkali solution mixed with carbonate as reaction raw materials to react with flue gas, for example, using Na2SO3, Na2S2O3, NaOH or NaOH+Na2CO3 to selectively remove NO x and SO x , achieving one-step desulfurization and denitrification treatment.

[0043] The absorbing section 301 at the lower part of the absorbing tower 3 washes the flue gas with the absorbing liquid delivered by the second storage tank to remove carbon dioxide in the flue gas. Optionally, the absorbing liquid uses an organic amine solution as a reaction raw material to react with the flue gas.

[0044] The cooling section 202 at the top of the pre-washing section washes the flue gas with the spray liquid delivered by the third storage tank to reduce the temperature of the flue gas to a temperature suitable for carbon capture. The washing section 302 at the top of the absorption tower 3 washes the flue gas with the spray liquid delivered by the third storage tank to wash away the droplets carried in the flue gas to avoid loss caused by the organic amine solution flowing away with the flue gas. Optionally, the spray liquid uses weak alkaline water.

[0045] like Figure 1and Figure 2 As shown, the integrated flue gas purification tower of the embodiment of the present invention also includes a water-cooled heat exchanger unit 7, which is located in the air-cooled tower 1. The water-cooled heat exchanger unit 7 is connected to the radiator group 101, the pre-washing tower 2 and the absorption tower 3 to utilize the cooling water naturally cooled by the radiator group 101 to cool the purified liquid, the absorption liquid and the spray liquid.

[0046] It can be understood that the liquid in each section of the pre-wash tower 2 and the absorption tower 3 is circulated, and during the circulation process, the cooling water of the air-cooled tower 1 is used to exchange heat and cool it to ensure a suitable temperature and guarantee the treatment effect.

[0047] Alternatively, if Figure 2 As shown, the water-cooled heat exchange unit 7 includes a water cooler for the purification section 201 of the pre-wash tower 2, a water cooler for the cooling section 202 of the pre-wash tower 2, a water cooler for the absorption section 301 of the absorption tower 3, and a water cooler for the washing section 302 of the absorption tower 3.

[0048] Furthermore, if Figure 2 As shown, the cooling section 202 and the washing section 302 are connected so that the spray liquid in the washing section 302 can be replenished into the cooling section 202. That is, the spray liquid used in the washing section 302 of the absorption section 301 can be reused in the cooling section 202 of the pre-washing tower 2, thereby improving the synergistic effect between the two processes.

[0049] For example, the temperature of the spray liquid flowing out of the washing section 302 of the absorption tower 3 is 25°C~35°C, and the temperature of the flue gas after desulfurization and denitrification flowing from the purification section 201 of the pre-washing tower 2 to the cooling section 202 is 45°C~55°C. The 25°C~35°C spray liquid is used to reduce the flue gas after desulfurization and denitrification at 45°C~55°C to about 40°C, which can meet the flue gas temperature suitable for carbon capture.

[0050] like Figure 1 As shown, the integrated flue gas purification tower of the embodiment of the present invention also includes a circulating pump unit 8, which is located in the air-cooled tower 1. The circulating pump unit 8 is connected to the radiator group 101, the pre-wash tower 2, the absorption tower 3, the solution tank group 6 and the water-cooled heat exchange unit 7. The circulating pump unit 8 is used to drive the liquid flow.

[0051] It can be understood that the circulation pipelines of cooling water between the radiator group 101 and the water-cooled heat exchanger unit 7, the circulation pipelines of each section of the pre-wash tower 2, and the circulation pipelines of each section of the absorption tower 3 are all driven by pumps to flow liquid.

[0052] like Figure 1 As shown, the integrated flue gas purification tower of the embodiment of the present invention also includes a waste liquid pool 9, which is located in the air-cooled tower 1. The waste liquid pool 9 is connected to the pre-washing tower 2 and the absorption tower 3. The waste liquid pool 9 is used to discharge the waste liquid generated by the pre-washing tower 2 and the absorption tower 3.

[0053] It can be understood that the waste liquid discharged during the operation of the pre-wash tower 2 and the absorption tower 3 flows to the waste liquid pool 9 for storage, and the waste liquid pool 9 is connected to the wastewater treatment system of the power plant.

[0054] In summary, the integrated flue gas purification tower of the embodiment of the present invention adopts the air-cooled tower 1 as the circulating cooling water supply equipment of the power plant, integrates the desulfurization, denitrification, carbon capture towers and related auxiliary equipment in the air-cooled tower 1, rationally utilizes the internal space of the air-cooled tower 1, and reduces the overall footprint.

[0055] Moreover, only two towers, the pre-wash tower 2 and the absorption tower 3, are needed to achieve flue gas purification, which shortens the flue gas flow. The air-cooled tower 1 is arranged around the pre-wash tower 2 and the absorption tower 3, which also shortens the cooling water flow. It not only improves the efficiency of flue gas purification, but also further reduces the overall footprint by shortening the distance of the pipeline.

[0056] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0057] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0058] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0059] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0060] In the present invention, the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" etc. mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the described specific features, structures, materials or characteristics may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0061] Although the above embodiments have been shown and described, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations on the present invention. Changes, modifications, substitutions and variations of the above embodiments by those of ordinary skill in the art are all within the scope of protection of the present invention.

Claims

1. An integrated flue gas purification tower, characterized in that: include: An air cooling tower, wherein the bottom wall of the air cooling tower is provided with a plurality of air inlet channels, the air cooling tower is provided with a plurality of conical radiator groups, the plurality of air inlet channels correspond to and are connected with the plurality of radiator groups one by one, the radiator groups extend in a vertical direction, and the air cooling tower is provided with a flue gas channel; A pre-washing tower, the pre-washing tower is located inside the air-cooling tower, the pre-washing tower is connected to the radiator group to provide cooling to the pre-washing tower, the pre-washing tower is connected to the flue gas channel, and the pre-washing tower includes a purification section and a cooling section arranged from bottom to top, so that the flue gas enters the purification section and the cooling section in sequence for desulfurization, denitrification and cooling; An absorption tower, wherein the absorption tower is located inside the air-cooled tower, the absorption tower is connected to the radiator group to provide cooling to the absorption tower, the absorption tower is connected to the pre-washing tower, and the absorption tower includes an absorption section and a washing section arranged from bottom to top, so that the flue gas passing through the pre-washing tower enters the absorption section and the washing section in turn for carbon capture and washing.

2. The integrated flue gas purification tower according to claim 1, characterized in that: It also includes a chimney, which is arranged on the top of the absorption tower. The pre-washing tower and the absorption tower are respectively connected to the chimney, so that the flue gas passing through the pre-washing tower and / or the absorption tower is discharged through the chimney.

3. The integrated flue gas purification tower according to claim 1, characterized in that: A booster fan is provided between the pre-wash tower and the absorption tower, and the booster fan is used to pressurize the flue gas flowing from the pre-wash tower to the absorption tower.

4. The integrated flue gas purification tower according to claim 1, characterized in that: It also includes a solution tank group, which is located in the air-cooled tower. The solution tank group includes a first storage tank, a second storage tank and a third storage tank. The first storage tank is connected to the purification section to transport purification liquid to the purification section, the second storage tank is connected to the absorption section to transport absorption liquid to the absorption section, and the third storage tank is connected to the cooling section and the washing section to transport spray liquid to the cooling section and the washing section.

5. The integrated flue gas purification tower according to claim 4, characterized in that: The purification liquid uses sulfite, thiosulfate and alkali solution or alkali solution mixed with carbonate as reaction raw materials to react with flue gas.

6. The integrated flue gas purification tower according to claim 4, characterized in that: The absorption liquid uses an organic amine solution as a reaction raw material to react with the flue gas.

7. The integrated flue gas purification tower according to any one of claims 4 to 6, characterized in that: It also includes a water-cooled heat exchange unit, which is located in the air-cooled tower and connected to the radiator group, the pre-wash tower and the absorption tower to utilize the cooling water naturally cooled by the radiator group to cool the purified liquid, the absorption liquid and the spray liquid.

8. The integrated flue gas purification tower according to claim 7, characterized in that: The cooling section is connected to the washing section so that the spray liquid in the washing section can be replenished into the cooling section.

9. The integrated flue gas purification tower according to claim 8, characterized in that: It also includes a circulating pump unit, which is located in the air-cooled tower. The circulating pump unit is connected to the radiator unit, the pre-wash tower, the absorption tower, the solution tank unit and the water-cooled heat exchange unit, and the circulating pump unit is used to drive the liquid to flow.

10. The integrated flue gas purification tower according to claim 1, characterized in that: It also includes a waste liquid pool, which is located in the air-cooled tower and connected to the pre-washing tower and the absorption tower. The waste liquid pool is used to discharge the waste liquid generated by the pre-washing tower and the absorption tower.

Images