Low temperature flue gas adsorption regeneration system

Abstract

The present application relates to the technical field of flue gas purification and discloses a low-temperature flue gas adsorption regeneration system, which comprises a cooling tower, an adsorption tower, a regeneration tower, an SCR reactor and a heat exchange pipe bundle, the cooling tower is used for cooling flue gas into low-temperature flue gas in a zero-temperature zone, the adsorption tower is in communication with the cooling tower, the adsorption tower is provided with an adsorbent, the inner cavity of the regeneration tower comprises a preheating section, a heating section and a cooling section arranged in sequence, the adsorbent inlet of the preheating section is connected with the adsorbent outlet of the adsorption tower, the SCR reactor is in communication with the tail flue of a boiler, the SCR reactor is connected with the cooling tower, the heat exchange pipe bundle is arranged in the SCR reactor, the heat exchange pipe bundle is provided with air, the air exchanges heat with flue gas in the SCR reactor, and the heat exchange pipe bundle is in communication with the preheating section. The low-temperature flue gas adsorption regeneration system can continuously produce a large amount of clean air with a certain temperature, avoids using an electric heater or other heating equipment to heat air, and reduces the energy consumption of the system.

Description

Technical Field

[0001] This application relates to the field of flue gas purification technology, and in particular to a low-temperature flue gas adsorption and regeneration system. Background Technology

[0002] The large amount of pollutants generated by coal-fired flue gas is a significant factor harming the atmospheric environment and human health. Low-temperature flue gas adsorption and regeneration systems utilize the principle of low-temperature adsorption to remove pollutant components from low-temperature flue gas. The adsorption capacity of the adsorbent is also increased exponentially under low-temperature conditions. Therefore, low-temperature flue gas adsorption and regeneration systems have significantly improved adsorption efficiency compared to conventional flue gas adsorption systems, promoting the development of near-zero emissions for flue gas.

[0003] In related technologies, low-temperature flue gas adsorption and regeneration systems generally use electric heaters to obtain high-temperature (e.g., 200℃-450℃) clean air. When a large amount of heat needs to be provided at once, it will result in a large load on the heater and high operating costs. Summary of the Invention

[0004] This invention is based on the inventor's discoveries and understanding of the following facts and problems:

[0005] In related technologies, a method of obtaining hot air by mixing heat exchange with an air preheater has been proposed. However, the hot air contains a lot of dust and cannot be used in situations requiring clean air. To address this, a method of installing a heat exchanger on the pipeline for coal-fired flue gas emissions has been proposed to exchange heat between the heat exchange medium and the high-temperature flue gas, which can realize the utilization of the waste heat of the flue gas. However, adding a heat exchanger to the pipeline changes the original layout of the flue gas pipeline and also requires providing space for the heat exchanger and fixing devices, making the project complex, cumbersome, and space-consuming.

[0006] The inventors recognized that flue gas temperatures vary at different locations along the emission path; for example, the flue gas inlet temperature of an SCR reactor is typically 250℃-400℃. The inventors proposed installing a heat exchanger inside the SCR reactor. Specifically, this heat exchanger, placed inside the SCR reactor, eliminates the need for a shell and consists solely of heat exchange tube bundles, allowing for direct installation within the reactor. This not only saves floor space, simplifies manufacturing costs, and reduces weight, but also allows for fixation within the SCR reactor's internal structure, reducing the difficulty of engineering modifications and avoiding the occupation of external space. Furthermore, in the heat exchanger located within the SCR reactor, the heat exchange medium, such as air, exchanges heat with the flue gas, generating a heat exchange medium at 200℃-300℃. This medium can then be introduced into the preheating section of the regeneration tower to preheat the adsorbent within the preheating section.

[0007] This invention aims to at least partially solve one of the technical problems in related technologies. To this end, this invention proposes a low-temperature flue gas adsorption and regeneration system, which can fully utilize the waste heat in boiler flue gas, reducing system energy consumption and production costs.

[0008] The low-temperature flue gas adsorption and regeneration system of the present invention includes:

[0009] Cooling tower, the cooling tower being used to cool flue gas introduced therein to a low temperature flue gas in the sub-zero temperature range;

[0010] An adsorption tower is connected to the cooling tower so that the low-temperature flue gas can enter the adsorption tower. The adsorption tower is equipped with an adsorbent for adsorbing and purifying the low-temperature flue gas.

[0011] The regeneration tower has an inner cavity comprising a preheating section for preheating the adsorbent, a heating section for heating the preheated adsorbent to regenerate the adsorbent, and a cooling section for cooling the regenerated adsorbent, arranged sequentially. The adsorbent inlet of the preheating section is connected to the adsorbent outlet of the adsorption tower so that the adsorbent in the adsorption tower can be introduced into the preheating section.

[0012] An SCR reactor is connected to the tail flue of the boiler and to the cooling tower, so that the SCR reactor purifies the flue gas discharged from the tail flue and supplies the purified flue gas to the cooling tower for cooling.

[0013] A heat exchange tube bundle is placed inside the SCR reactor. The heat exchange tube bundle contains air, which exchanges heat with the flue gas inside the SCR reactor. The heat exchange tube bundle is connected to the preheating section so that the air that has exchanged heat in the heat exchange tube bundle can enter the preheating section to preheat the adsorbent in the preheating section.

[0014] The low-temperature flue gas adsorption regeneration system of the present invention installs a heat exchange tube bundle inside the SCR reactor so that the air introduced into the heat exchange tube bundle can continuously exchange heat with the flue gas in the SCR reactor, thereby continuously generating a large amount of clean air, avoiding the use of heating equipment such as electric heaters to heat the air, and reducing the energy consumption of the system.

[0015] Optionally, the SCR reactor includes a shell and a support component disposed within the shell, a denitrification catalyst disposed on the support component, the denitrification catalyst being used to purify the flue gas, and the heat exchange tube bundle disposed on the support component.

[0016] The heat exchange tube bundle of the low-temperature flue gas adsorption regeneration system of the present invention can be installed using the internal structure of the SCR reactor, that is, the heat exchange tube bundle is installed on the support component of the denitrification catalyst, avoiding modification of the internal structure of the SCR reactor, reducing damage to the internal structure of the SCR reactor, and reducing installation difficulty.

[0017] Optionally, the denitrification catalyst and the heat exchange tube bundle are arranged sequentially in the flow direction of the flue gas.

[0018] In the low-temperature flue gas adsorption regeneration system of the present invention, the denitrification catalyst is located upstream of the heat exchange tube bundle, so that the flue gas can first contact the denitrification catalyst and treat the impurities in the flue gas, reducing the impurity content in the flue gas. This reduces the scouring of the heat exchange tube bundle by the flue gas, reduces the accumulation of flue gas impurities in the heat exchange tube bundle, and thus ensures the heat exchange effect of the heat exchange tube bundle.

[0019] Optionally, the heat exchange tube bundle is detachably connected to the support member.

[0020] The heat exchange tube bundle and support components of the low-temperature flue gas adsorption regeneration system of the present invention can be detachably connected by snap-fit ​​or by bolts or other connecting parts, which facilitates the assembly and disassembly of the heat exchange tube bundle.

[0021] Optionally, the low-temperature flue gas adsorption regeneration system of the present invention further includes a heat exchanger having a cold-side inlet, a cold-side outlet, a hot-side outlet, and a hot-side inlet. The tail flue has a first flue port and a second flue port arranged sequentially in the flow direction of the flue gas. The first flue port is connected to the hot-side inlet, and the second flue port is connected to the hot-side outlet. The cold-side inlet is used to introduce air to exchange heat with the flue gas entering the heat exchanger from the hot-side inlet. The cold-side outlet is connected to the heating section so that the air after heat exchange in the heat exchanger enters the heating section to heat the adsorbent.

[0022] The heat exchanger of the low-temperature flue gas adsorption regeneration system of the present invention is connected to the tail flue so that the air in the heat exchanger can exchange heat with the flue gas discharged from the tail flue. The temperature of the air after heat exchange in the heat exchanger is higher than the temperature of the air after heat exchange in the heat exchange tube bundle, so as to be used in different temperature scenarios and further improve the utilization rate of boiler flue gas waste heat.

[0023] Optionally, the tail flue has a downstream flue outlet connected to the SCR reactor, and the downstream flue outlet is located downstream of the first flue outlet and the second flue outlet along the flue gas flow direction in the tail flue.

[0024] In the low-temperature flue gas adsorption regeneration system of the present invention, the first flue gas outlet, the second flue gas outlet, and the downstream flue gas outlet are arranged sequentially and at intervals along the flue gas flow direction on the tail flue, thereby ensuring that the flue gas temperature discharged from the first flue gas outlet is greater than the flue gas temperature entering the second flue gas outlet, and that the flue gas temperature entering the second flue gas outlet is greater than the flue gas temperature discharged from the downstream flue gas outlet, so that the flue gas temperature in the tail flue always gradually decreases in the flue gas flow direction, ensuring the stability of heat exchange in the heat exchanger or heat exchange tube bundle.

[0025] Optionally, there are multiple first smoke outlets and multiple second smoke outlets, with the multiple first smoke outlets arranged at intervals along the circumference of the tail flue, and the multiple second smoke outlets arranged at intervals along the circumference of the tail flue.

[0026] The low-temperature flue gas adsorption and regeneration system of the present invention can arrange different numbers of first flue gas outlets and second flue gas outlets according to the required amount of air after heat exchange. Correspondingly, multiple heat exchangers corresponding one-to-one with multiple first flue gas outlets can also be arranged to meet different needs.

[0027] Optionally, the cooling section has a cooling inlet and a cooling outlet. The cooling inlet is connected to the adsorption tower so that at least a portion of the purified flue gas after adsorption is introduced into the cooling section to cool the adsorbent in the cooling section. The cooling outlet is connected to the cold side inlet of the heat exchanger.

[0028] The low-temperature flue gas adsorption and regeneration system of this invention introduces the purified flue gas, after heat exchange with the adsorbent in the cooling section, into a heat exchanger for further heat exchange with the flue gas. The purified flue gas is then introduced into a regeneration tower, thereby realizing the utilization of waste heat from the boiler flue gas. Furthermore, by connecting the cooling inlet to the adsorption tower, the cooled purified flue gas discharged from the adsorption tower can cool the adsorbent in the cooling section, thus achieving the reuse of the cooled flue gas.

[0029] Optionally, the heating section has a heating inlet and a heating outlet. The heating inlet is connected to the cold-side outlet of the heat exchanger so that the clean flue gas after heat exchange in the heat exchanger is introduced into the heating section to heat the adsorbent. The heating outlet is connected to the heat exchange tube bundle so that the clean flue gas after heat exchange in the heating section to heat the adsorbent is introduced into the heat exchange tube bundle. The preheating section has a preheating inlet and a preheating outlet. The preheating inlet is connected to the heat exchange tube bundle so that the clean flue gas after heat exchange in the heat exchange tube bundle is introduced into the preheating section to preheat the adsorbent.

[0030] In the low-temperature flue gas adsorption and regeneration system of the present invention, the clean flue gas after heat exchange in the heating section can be introduced into the heat exchange tube bundle to exchange heat with the flue gas in the SCR reactor, thereby further utilizing the waste heat of the flue gas.

[0031] Optionally, the low-temperature flue gas adsorption and regeneration system of the present invention further includes a mixer connected between the heat exchange tube bundle and the preheating inlet. The mixer has an adjustment port for introducing temperature-regulating air into the mixer. The temperature-regulating clean flue gas is mixed with the clean flue gas discharged from the heat exchange tube bundle in the mixer to adjust the temperature of the clean flue gas before entering the preheating section.

[0032] The low-temperature flue gas adsorption and regeneration system of the present invention can use a mixer to adjust the temperature of the clean flue gas introduced into the mixer so that the temperature of the clean flue gas in the mixer can meet the preheating requirements of the preheating section. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the low-temperature flue gas adsorption and regeneration system of the present invention.

[0034] Figure 2 This is a partial structural schematic diagram of the low-temperature flue gas adsorption and regeneration system of the present invention.

[0035] Figure 3 This is a cross-sectional schematic diagram of the permeable shell of the low-temperature flue gas adsorption and regeneration system of the present invention.

[0036] Figure label:

[0037] Breathable outer shell 100;

[0038] Regeneration tower 1; Regeneration inlet 11; Regeneration outlet 12;

[0039] Preheating section 17; Preheating inlet 171; Preheating outlet 172;

[0040] Heating section 18; heating inlet 181; heating outlet 182;

[0041] Cooling section 19; Cooling inlet 191; Cooling outlet 192;

[0042] Heat exchanger tube bundle 2;

[0043] Boiler 3; Tail flue 31; First flue outlet 311; Second flue outlet 312; Downstream flue outlet 313;

[0044] SCR reactor 4;

[0045] Heat exchanger 5; hot side inlet 51; hot side outlet 52; cold side inlet 53; cold side outlet 54;

[0046] Mixer 6; Adjustment port 61;

[0047] Cooling tower 7;

[0048] Adsorption tower 8; Adsorbent inlet 81; Adsorbent outlet 82. Detailed Implementation

[0049] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0050] The low-temperature flue gas adsorption and regeneration system of the present invention will now be described with reference to the accompanying drawings.

[0051] like Figures 1-3 As shown, the low-temperature flue gas adsorption and regeneration system of the present invention includes: a cooling tower 7, an adsorption tower 8, a regeneration tower 1, an SCR reactor 4, and a heat exchange tube bundle 2.

[0052] Cooling tower 7 is used to cool the flue gas introduced into it to a low-temperature flue gas in the sub-zero temperature range. Adsorption tower 8 is connected to cooling tower 7 so that the low-temperature flue gas can enter adsorption tower 8. Adsorption tower 8 contains adsorbent, which is used to adsorb and purify the low-temperature flue gas. The inner cavity of regeneration tower 1 includes a preheating section 17 for preheating the adsorbent, a heating section 18 for heating the preheated adsorbent to regenerate the adsorbent, and a cooling section 19 for cooling the regenerated adsorbent. The adsorbent inlet 11 of adsorption tower 1 is connected to the regeneration outlet 12 of regeneration tower 1 so that the adsorbent in regeneration tower 1 can be introduced into preheating section 17 through adsorbent inlet 11.

[0053] Specifically, such as Figure 1 As shown, the exhaust port of cooling tower 7 is connected to the inlet of adsorption tower 8 via a pipe, allowing the flue gas cooled by cooling tower 7 to enter adsorption tower 8. Adsorption tower 8 may contain multiple adsorption layers, with adsorbent placed within each layer to adsorb and purify the flue gas entering it. The regeneration inlet 11 of regeneration tower 1 is connected to the adsorbent outlet 82 of adsorption tower 8, and the regeneration outlet 12 of regeneration tower 1 is connected to the adsorbent inlet 81 of adsorption tower 8, allowing the adsorbent to circulate between adsorption tower 8 and regeneration tower 1.

[0054] It should be noted that, as Figure 3As shown, the adsorbent can be filled inside the permeable shell 100 for adsorption. The adsorbent can be granular or powdered, or it can be an adsorbent body made of powder or granular adsorbent, such as a spherical or cylindrical body formed by binding powder or granular adsorbent with a binder. Of course, a protective shell can be further formed on the outside of the adsorbent body, such as a permeable membrane covering the outside of the adsorbent body, to improve the strength of the adsorbent body. The permeable shell has vents, through which flue gas can enter the permeable shell. The flue gas can pass through the gaps between adjacent adsorbents and / or the pores of the adsorbent itself, thereby reducing direct collisions, friction and wear between adsorbents, and dust generation. The permeable shell can be in the shape of a sphere, cylinder, or other rotating body, wherein the diameter of the permeable shell 100 is 10mm-100mm, and the diameter of the adsorbent is 1mm-10mm.

[0055] The SCR reactor 4 is connected to the tail flue 31 of the boiler 3 and to the cooling tower 7 so that the SCR reactor 4 purifies the flue gas discharged from the tail flue 31 and supplies the purified flue gas to the cooling tower 7 for cooling.

[0056] Specifically, such as Figure 1 and Figure 2 As shown, the flue gas discharged from the tail flue 31 of boiler 3 can be introduced into SCR reactor 4. The flue gas outlet of SCR reactor 4 is connected to the flue gas inlet of cooling tower 7 through a pipeline, so that the flue gas discharged from SCR reactor 4 can be introduced into cooling tower 7. Cooling tower 7 can cool the flue gas to below zero and form clean flue gas for discharge, so that the clean flue gas with a temperature below zero can be introduced into adsorption tower 8 to ensure the adsorption and purification effect of adsorbent.

[0057] Preferably, the cooling tower 7 is capable of cooling the clean flue gas to -20°C to -15°C.

[0058] The heat exchange tube bundle 2 is placed inside the SCR reactor 4. The heat exchange tube bundle 2 contains air, which exchanges heat with the flue gas in the SCR reactor 4. The heat exchange tube bundle 2 is connected to the preheating section 17 so that the air after heat exchange in the heat exchange tube bundle 2 can enter the preheating section 17 to preheat the adsorbent in the preheating section 17.

[0059] Understandably, removing the original outer shell of the heat exchanger tube bundle 2 and installing it directly inside the SCR reactor 4 can not only save floor space, simplify the manufacturing cost of the heat exchanger 5, and reduce weight, but also utilize the internal structure of the SCR reactor 4 to fix the heat exchanger 5, thereby reducing the difficulty of engineering modification and avoiding the occupation of external space.

[0060] Since the flue gas temperature at the inlet of SCR reactor 4 is generally 250℃-400℃, the air in the heat exchange tube bundle 2 can generate air at 200℃-300℃ after exchanging heat with the flue gas in SCR reactor 4. According to different needs, the air with this temperature can be used to heat other equipment (such as the preheating section 17 of regeneration tower 1) to ensure the reuse of flue gas waste heat.

[0061] Therefore, the low-temperature flue gas adsorption regeneration system of the present invention installs the heat exchange tube bundle 2 inside the SCR reactor 4 so that the air introduced into the heat exchange tube bundle 2 can continuously exchange heat with the flue gas in the SCR reactor 4, thereby continuously generating a large amount of clean air, avoiding the use of heating equipment such as electric heaters to heat the air, and reducing the energy consumption of the system.

[0062] Furthermore, the low-temperature flue gas adsorption and regeneration system of the present invention can also install different numbers of heat exchange tube bundles 2 in the SCR reactor 4 as needed to further increase heat exchange with flue gas, so as to generate more heat exchange air and improve the reuse of flue gas waste heat.

[0063] In other words, the low-temperature flue gas adsorption regeneration system of the present invention can utilize the waste heat of flue gas to heat air for reuse. For example, the heated air can be introduced into the preheating section 17 of the regeneration tower 1 to preheat the adsorbent in the preheating section 17. Compared with directly heating air with an electric heater, the present invention avoids the use of electricity, thereby reducing the electricity consumption of the low-temperature flue gas adsorption regeneration system of the present invention by at least 30%.

[0064] Optionally, the SCR reactor 4 includes a shell and a support component disposed within the shell. A denitrification catalyst is disposed on the support component. The denitrification catalyst is used to purify flue gas. The heat exchange tube bundle 2 is disposed on the support component.

[0065] Understandably, the support components inside the SCR reactor 4 are used to install the denitrification catalyst, so that the denitrification catalyst can be used to treat the flue gas inside the SCR reactor 4 to achieve the function of purifying the flue gas. The support components can be support rods or support protrusions connected to the inner wall of the SCR reactor 4, as long as they can accommodate the denitrification catalyst.

[0066] In other words, the heat exchange tube bundle 2 of the low-temperature flue gas adsorption regeneration system of the present invention can be installed using the internal structure of the SCR reactor 4, that is, the heat exchange tube bundle 2 is installed on the support component of the denitrification catalyst, avoiding modification of the internal structure of the SCR reactor 4, reducing damage to the internal structure of the SCR reactor 4, and reducing installation difficulty.

[0067] Optionally, the denitrification catalyst and the heat exchange tube bundle 2 are arranged sequentially in the direction of flue gas flow.

[0068] It is understandable that the flue gas in the SCR reactor 4 sequentially washes the denitrification catalyst and the heat exchange tube bundle 2, that is, the flue gas in the SCR reactor 4 can be purified by the denitrification catalyst before washing the heat exchange tube bundle 2.

[0069] In other words, the denitrification catalyst of the low-temperature flue gas adsorption regeneration system of the present invention is located upstream of the heat exchange tube bundle 2, so that the flue gas can first contact the denitrification catalyst and treat the impurities in the flue gas, reducing the impurity content in the flue gas, thereby reducing the scouring of the heat exchange tube bundle 2 by the flue gas, reducing the accumulation of flue gas impurities in the heat exchange tube bundle 2, and thus ensuring the heat exchange effect of the heat exchange tube bundle 2.

[0070] Optionally, the heat exchange tube bundle 2 is detachably connected to the support component. It is understood that the heat exchange tube bundle 2 and the support component of the low-temperature flue gas adsorption regeneration system of the present invention can be detachably connected by snap-fit ​​or by bolts or other connecting parts, which facilitates the assembly and disassembly of the heat exchange tube bundle 2.

[0071] Preferably, such as Figure 1 As shown, the heat exchange tube bundle 2 is located inside the SCR reactor 4 near the flue gas outlet (i.e., in the lower part of the SCR reactor 4) to avoid clogging the flue gas entering the SCR reactor 4. Furthermore, the lower part of the SCR reactor 4's interior also allows the flue gas to fully flow within the SCR reactor 4 before contacting the heat exchange tube bundle 2, thus improving the heat exchange efficiency between the flue gas and the heat exchange tube bundle 2.

[0072] Optionally, the low-temperature flue gas adsorption regeneration system of the present invention further includes a heat exchanger 5, which has a cold-side inlet 53, a cold-side outlet 54, a hot-side outlet 52, and a hot-side inlet 51. The tail flue 31 has a first flue port 311 and a second flue port 312 arranged sequentially in the flue gas flow direction. The first flue port 311 is connected to the hot-side inlet 51, and the second flue port 312 is connected to the hot-side outlet 52. The cold-side inlet 53 is used to introduce air to exchange heat with the flue gas entering the heat exchanger 5 from the hot-side inlet 51. The cold-side outlet 54 is connected to the heating section 18 so that the air after heat exchange in the heat exchanger 5 enters the heating section 18 to heat the adsorbent.

[0073] Specifically, such as Figure 1 and Figure 2 As shown, the first flue gas outlet 311 is located upstream of the second flue gas outlet 312. The temperature of the flue gas discharged from the first flue gas outlet 311 is higher than the temperature of the flue gas entering the second flue gas outlet. This is to prevent the flue gas from causing turbulence in the tail flue 31 when it returns to the tail flue 31, thus avoiding uneven temperature distribution of the flue gas.

[0074] The heat exchanger 5 of the low-temperature flue gas adsorption regeneration system of the present invention is connected to the tail flue 31 so that the air in the heat exchanger 5 can exchange heat with the flue gas discharged from the tail flue 31, and the temperature of the air after heat exchange in the heat exchanger 5 is higher than the temperature of the air after heat exchange in the heat exchange tube bundle 2, so as to be used in different temperature scenarios and further improve the utilization rate of waste heat of flue gas in boiler 3.

[0075] Optionally, the tail flue 31 has a downstream flue outlet 313 connected to the SCR reactor 4. The downstream flue outlet 313 is located downstream of the first flue outlet 311 and the second flue outlet 312 along the flue gas flow direction in the tail flue 31.

[0076] It is understood that the first flue gas outlet 311, the second flue gas outlet 312, and the downstream flue gas outlet 313 of the low-temperature flue gas adsorption and regeneration system of the present invention are arranged sequentially and at intervals along the flue gas flow direction on the tail flue duct 31, thereby ensuring that the flue gas temperature discharged from the first flue gas outlet 311 is greater than the flue gas temperature entering the second flue gas outlet 312, and the flue gas temperature entering the second flue gas outlet 312 is greater than the flue gas temperature discharged from the downstream flue gas outlet 313, so that the flue gas temperature in the tail flue duct 31 always gradually decreases in the flue gas flow direction, ensuring the stability of heat exchange in the heat exchanger 5 or the heat exchange tube bundle 2.

[0077] Preferably, there are multiple first flue outlets 311 and multiple second flue outlets 312. The multiple first flue outlets 311 are arranged at intervals along the circumference of the tail flue 31, and the multiple second flue outlets 312 are arranged at intervals along the circumference of the tail flue 31.

[0078] The low-temperature flue gas adsorption and regeneration system of the present invention can arrange different numbers of first flue gas outlets 311 and second flue gas outlets 312 according to the required amount of air after heat exchange. Correspondingly, multiple heat exchangers 5 corresponding one-to-one with multiple first flue gas outlets 311 can also be arranged to meet different needs.

[0079] Optionally, the cooling section 19 has a cooling inlet 191 and a cooling outlet 192. The cooling inlet 191 is connected to the adsorption tower 8 so that at least a portion of the purified flue gas after adsorption is passed into the cooling section 19 to cool the adsorbent in the cooling section 19. The cooling outlet 192 is connected to the cold side inlet 53 of the heat exchanger 5.

[0080] Specifically, such as Figure 1 and Figure 2 As shown, the cooling inlet 191 is located below the cooling outlet 192, and the adsorbent in the regeneration tower 1 flows from top to bottom, thereby ensuring that the clean flue gas entering the cooling section 19 comes into countercurrent contact with the adsorbent in the regeneration tower 1, thus improving the cooling effect.

[0081] The low-temperature flue gas adsorption and regeneration system of the present invention introduces the clean flue gas after heat exchange with the adsorbent in the cooling section 19 into the heat exchanger 5 for heat exchange with the flue gas, and then introduces the clean flue gas after heat exchange into the regeneration tower 1, thereby realizing the utilization of waste heat of the flue gas of boiler 3.

[0082] Optionally, the heating section 18 has a heating inlet 181 and a heating outlet 182. The heating inlet 181 is connected to the cold side outlet 54 of the heat exchanger 5 so that the clean flue gas after heat exchange in the heat exchanger 5 is introduced into the heating section 18 to heat the adsorbent. The heating outlet 182 is connected to the heat exchange tube bundle 2 so that the clean flue gas after heat exchange in the heating section 18 to heat the adsorbent is introduced into the heat exchange tube bundle 2. The preheating section 17 has a preheating inlet 171 and a preheating outlet 172. The preheating inlet 171 is connected to the heat exchange tube bundle 2 so that the clean flue gas after heat exchange in the heat exchange tube bundle 2 is introduced into the preheating section 17 to preheat the adsorbent.

[0083] Specifically, such as Figure 1 and Figure 2 As shown, the heating inlet 181 is located below the heating outlet 182. The clean flue gas discharged from the cooling outlet 192 exchanges heat with the flue gas discharged from the tail flue 31 in the heat exchanger 5, so that the temperature of the clean flue gas is heated to 300℃-450℃. This ensures that the clean flue gas entering the heating section 18 through the heating inlet 181 can heat the adsorbent in the heating section 18, thereby causing the adsorbent in the heating section 18 to be desorbed by heat.

[0084] In the low-temperature flue gas adsorption regeneration system of the present invention, the clean flue gas after heat exchange in the heating section 18 can be introduced into the heat exchange tube bundle 2 to exchange heat with the flue gas in the SCR reactor, thereby further utilizing the waste heat of the flue gas.

[0085] Optionally, the low-temperature flue gas adsorption regeneration system of the present invention further includes a mixer 6, which is connected between the heat exchange tube bundle 2 and the preheating inlet 171. The mixer 6 has an adjustment port 61 for introducing temperature-regulating air into the mixer 6. The temperature-regulating clean flue gas is mixed with the clean flue gas discharged from the heat exchange tube bundle 2 in the mixer 6 to adjust the temperature of the clean flue gas before entering the preheating section 17.

[0086] It is understandable that the preheating temperature required for the preheating section 17 of the regeneration tower 1 is generally 80℃-100℃. The temperature of the clean flue gas after heat exchange in the heat exchange tube bundle 2 may be slightly higher than the preheating temperature required for the preheating section 17. Therefore, preferably, the clean flue gas after heat exchange in the heat exchange tube bundle 2 can be first introduced into the mixer 6, and then temperature-controlled air (i.e., ambient temperature air) or low-temperature clean flue gas can be introduced into the mixer 6 to reduce the temperature of the clean flue gas after heat exchange to the preheating temperature required for the preheating section 17.

[0087] It should be noted that, as Figure 1As shown, the exhaust port of the cooling tower 7 can also be connected to the regulating port 61 of the mixer 6. Since the temperature of the exhaust gas discharged from the cooling tower 7 is below 0°C, the clean exhaust gas after heat exchange can be quickly cooled to the preheating temperature required by the preheating section 17 in the mixer 6.

[0088] The low-temperature flue gas adsorption and regeneration system of the present invention can use the mixer 6 to perform temperature control on the clean flue gas introduced into the mixer 6, so that the temperature of the clean flue gas in the mixer 6 can reach the temperature required for preheating in the preheating section 17.

[0089] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0090] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0091] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0092] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0093] In this invention, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0094] Although the above embodiments have been shown and described, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Any changes, modifications, substitutions and variations made to the above embodiments by those skilled in the art are within the protection scope of the present invention.

Claims

1. A low-temperature flue gas adsorption and regeneration system, characterized in that, include: Cooling tower, the cooling tower being used to cool flue gas introduced therein to a low temperature flue gas in the sub-zero temperature range; An adsorption tower is connected to the cooling tower so that the low-temperature flue gas can enter the adsorption tower. The adsorption tower is equipped with an adsorbent for adsorbing and purifying the low-temperature flue gas. The regeneration tower has an inner cavity comprising a preheating section for preheating the adsorbent, a heating section for heating the preheated adsorbent to regenerate the adsorbent, and a cooling section for cooling the regenerated adsorbent, arranged sequentially. The adsorbent inlet of the preheating section is connected to the adsorbent outlet of the adsorption tower so that the adsorbent in the adsorption tower can be introduced into the preheating section. An SCR reactor is connected to the tail flue of the boiler and to the cooling tower, so that the SCR reactor purifies the flue gas discharged from the tail flue and supplies the purified flue gas to the cooling tower for cooling. A heat exchange tube bundle is placed inside the SCR reactor. The heat exchange tube bundle contains air, which exchanges heat with the flue gas inside the SCR reactor. The heat exchange tube bundle is connected to the preheating section so that the air after heat exchange in the heat exchange tube bundle can enter the preheating section to preheat the adsorbent in the preheating section. A heat exchanger having a cold-side inlet, a cold-side outlet, a hot-side outlet, and a hot-side inlet, wherein the tail flue has a first flue port and a second flue port arranged sequentially in the flow direction of the flue gas, the first flue port being connected to the hot-side inlet, the second flue port being connected to the hot-side outlet, the cold-side inlet being used to introduce air to exchange heat with the flue gas entering the heat exchanger from the hot-side inlet, and the cold-side outlet being connected to the heating section so that the air after heat exchange in the heat exchanger enters the heating section to heat the adsorbent; The cooling section has a cooling inlet and a cooling outlet. The cooling inlet is connected to the adsorption tower so that at least a portion of the purified flue gas is introduced into the cooling section to cool the adsorbent in the cooling section. The cooling outlet is connected to the cold side inlet of the heat exchanger. The heating section has a heating inlet and a heating outlet. The heating inlet is connected to the cold-side outlet of the heat exchanger so that the clean flue gas, after heat exchange in the heat exchanger, enters the heating section to heat the adsorbent. The heating outlet is connected to the heat exchange tube bundle so that the clean flue gas, after heating the adsorbent in the heating section, enters the heat exchange tube bundle. The preheating section has a preheating inlet and a preheating outlet. The preheating inlet is connected to the heat exchange tube bundle so that the clean flue gas after heat exchange in the heat exchange tube bundle is introduced into the preheating adsorbent of the preheating section.

2. The low-temperature flue gas adsorption and regeneration system according to claim 1, characterized in that, The SCR reactor includes a shell and a support component disposed within the shell. A denitrification catalyst is disposed on the support component for purifying the flue gas. The heat exchange tube bundle is disposed on the support component.

3. The low-temperature flue gas adsorption and regeneration system according to claim 2, characterized in that, The denitrification catalyst and the heat exchange tube bundle are arranged sequentially in the direction of flue gas flow.

4. The low-temperature flue gas adsorption and regeneration system according to claim 3, characterized in that, The heat exchange tube bundle is detachably connected to the support component.

5. The low-temperature flue gas adsorption and regeneration system according to claim 1, characterized in that, The tail flue has a downstream flue outlet connected to the SCR reactor, and the downstream flue outlet is located downstream of the first flue outlet and the second flue outlet along the flue gas flow direction in the tail flue.

6. The low-temperature flue gas adsorption and regeneration system according to claim 5, characterized in that, There are multiple first smoke outlets and multiple second smoke outlets. The multiple first smoke outlets are arranged at intervals along the circumference of the tail flue, and the multiple second smoke outlets are arranged at intervals along the circumference of the tail flue.

7. The low-temperature flue gas adsorption and regeneration system according to claim 1, characterized in that, It also includes a mixer connected between the heat exchange tube bundle and the preheating inlet. The mixer has an adjustment port for introducing temperature-controlled air into the mixer. The temperature-controlled air is mixed with the clean flue gas discharged from the heat exchange tube bundle in the mixer to adjust the temperature of the air before it enters the preheating section.

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