A device and method for removing nitrogen oxide-containing flue gas by adsorption

Abstract

The present application relates to industrial waste gas removal treatment technical field, specifically disclose a kind of nitrogen oxide-containing flue gas adsorption removal device and removal method;Including adsorption tower, ozone generator, water separator, pre-cooler and ozone removal device;Adsorption tower gas inlet end is connected water separator and ozone generator by pipeline, and the gas outlet end of adsorption tower is connected with ozone removal device by pipeline, water separator gas inlet end is connected pre-cooler by pipeline, and the gas inlet end of pre-cooler is connected boiler by pipeline;Wherein, the gas outlet end of water separator is provided with nitric oxide concentration sensor, and the gas outlet end of ozone generator is provided with ozone concentration sensor;Molecular sieve adsorbent is provided in adsorption tower;Nitrogen dioxide generated is absorbed by setting molecular sieve adsorbent in adsorption tower, realizes zero emission of nitrogen oxide, and the gas outlet end of adsorption tower is connected with ozone removal device, and the excess ozone is adsorbed by ozone removal device, effectively prevent secondary pollution caused by ozone.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of industrial waste gas removal treatment, in particular to a nitrogen oxide-containing flue gas adsorption removal device and method. BACKGROUND

[0002] Nitrogen oxides are one of the main atmospheric pollutants, mainly from fossil fuel combustion and waste gas generated in the industries of chemical fertilizer, pharmaceutical, organic synthesis, metal smelting, electronics, etc. Nitrogen oxides not only cause the formation of acid rain, but also cause the formation of photochemical smog, ozone layer destruction and other problems. In addition, if nitrogen oxides are inhaled into the human body, not only will it cause great harm to the nervous system, but also will have strong corrosion and stimulation effect on the respiratory system. Therefore, the treatment of nitrogen oxides has important social needs and practical significance.

[0003] The Chinese patent with publication number CN110743312A and publication date of 2020-02-04 discloses a flue gas low-temperature adsorption denitration system and process, which discloses a system including a booster fan, a cold energy recovery device, a flue gas cooling system, a flue gas switching valve and a denitration adsorption tower; wherein the inlet of the booster fan is in communication with the inlet flue gas pipeline, the booster fan, the cold energy recovery device, the flue gas cooling system, the flue gas switching valve and the denitration adsorption tower are in communication in sequence, the outlet of the flue gas switching valve is in communication with the first denitration adsorption tower and the second denitration adsorption tower respectively, the flue gas outlets of the first denitration adsorption tower and the second denitration adsorption tower are in communication with the flue gas flow combiner, and the flue gas flow combiner is in communication with the cold energy recovery device; the adsorption denitration system and process realize the adsorption removal of most nitrogen oxides, but since the content of NO in flue gas NOx is the highest and NO is a gas that is extremely difficult to adsorb, the adsorption of NO in the prior art is carried out by oxidizing NO into NO2 by introducing O2, but since O2 and NO have a slow oxidation reaction at low temperature, the content of NO in flue gas is high, and the adsorbed NO2 is prone to disproportionation reaction, resulting in the re-generation of NO, so in the actual adsorption and removal process, the adsorption denitration system and process cannot efficiently adsorb and remove nitrogen oxides, and is prone to secondary pollution emission.

[0004] In the prior art, the ozone ion plasma oxidation method is used in the pre-oxidation method, in order to ensure that flue gas NOx is completely oxidized, a large amount of ozone is often introduced, resulting in high ozone use cost, and the excess ozone introduced is directly discharged without being effectively removed, which is prone to secondary pollution emission. SUMMARY

[0005] The present application aims to at least solve one of the technical problems existing in the prior art. To this end, the present application provides a nitrogen oxide-containing flue gas adsorption removal device and method.

[0006] According to the nitrogen oxide-containing flue gas adsorption removal device and removal method, the nitrogen oxide-containing flue gas is introduced into the adsorption tower, the ozone is generated by the ozone generator, the ozone is introduced into the nitrogen oxide-containing flue gas, the nitrogen monoxide is oxidized into the nitrogen dioxide due to the strong oxidizability of the ozone, the data is measured by the nitrogen monoxide concentration sensor and the ozone concentration sensor, the opening degree of the electromagnetic valve is controlled to control the molar ratio of the nitrogen monoxide oxidation and the ozone, the nitrogen monoxide is completely oxidized into the nitrogen dioxide, a small amount of the ozone is generated, the disproportionation reaction of the nitrogen dioxide is inhibited, the ozone consumption is further reduced, the molecular sieve adsorbent is arranged in the adsorption tower to absorb the generated nitrogen dioxide, the ozone and the adsorbent are prevented from reacting due to the stable chemical property of the molecular sieve, the ozone removal device is connected to the gas outlet end of the adsorption tower, the active carbon screen plates are arranged in the ozone removal device, the reset springs are arranged at the two ends of the active carbon screen plates, the cam mechanism drives the active carbon screen plates to reciprocate, the active carbon is prevented from being caked, the active carbon completely reacts with and absorbs the excess ozone, and the secondary pollution of the ozone is effectively prevented.

[0007] The adsorption tower, the ozone generator, the water separator, the pre-cooler and the ozone removal device are connected by pipelines.

[0008] The ozone removal device is provided with a plurality of active carbon screen plates which are arranged at intervals in the ozone removal device, the two ends of the active carbon screen plates are slidably connected with the limiting plates, the two ends of the active carbon screen plates are connected with the bottom wall of the sliding groove of the limiting plates through the reset springs, the limiting plates are installed on the inner wall of the ozone removal device, the active carbon screen plates are uniformly provided with through holes, the connecting plates are connected between the active carbon screen plates, and the ozone removal device is provided with a cam which abuts against the connecting plates.

[0009] According to the nitrogen oxide-containing flue gas adsorption removal device and removal method, the ozone generated by the ozone generator is introduced into the nitrogen oxide-containing flue gas, the nitrogen monoxide is oxidized into the nitrogen dioxide due to the strong oxidizability of the ozone, the data is measured by the nitrogen monoxide concentration sensor and the ozone concentration sensor, the opening degree of the electromagnetic valve is controlled to control the molar ratio of the nitrogen monoxide oxidation and the ozone, the nitrogen monoxide is completely oxidized into the nitrogen dioxide, a small amount of the ozone is generated, the disproportionation reaction of the nitrogen dioxide is inhibited, the ozone consumption is further reduced, the molecular sieve adsorbent is arranged in the adsorption tower to absorb the generated nitrogen dioxide, the ozone and the adsorbent are prevented from reacting due to the stable chemical property of the molecular sieve, the ozone removal device is connected to the gas outlet end of the adsorption tower, the active carbon screen plates are arranged in the ozone removal device, the reset springs are arranged at the two ends of the active carbon screen plates, the cam mechanism drives the active carbon screen plates to reciprocate, the active carbon is prevented from being caked, the active carbon completely reacts with and absorbs the excess ozone, and the secondary pollution of the ozone is effectively prevented.

[0010] According to some embodiments of the present application, the gas outlet end of the boiler is further connected with a booster fan, an air preheater and a dust collector in sequence, the gas outlet end of the dust collector is connected with the pre-cooler, the gas outlet end of the pre-cooler is provided with a temperature sensor, and the ozone generator outlet pipeline is provided with an electromagnetic valve; the booster fan is arranged to guide the flue gas generated by the boiler to the adsorption tower, the air preheater is arranged to perform heat exchange between the flue gas and the air entering the boiler, and the heat utilization rate of the flue gas is improved; the pre-cooler is arranged to cool the flue gas to below 80℃, so as to avoid decomposition of ozone due to excessively high temperature of the flue gas.

[0011] According to some embodiments of the present application, the bottom adsorbent outlet of the adsorption tower is connected with an adsorbent regeneration tower, the gas inlet end of the adsorbent regeneration tower is connected with a heat source input device through a pipeline, and the adsorbent regeneration tower is connected with an alkali liquor adsorption device through a pipeline, and the alkali liquor adsorption device is used to absorb and process nitrogen oxides desorbed from the adsorbent by heating; the high-temperature flue gas guided by the heat source input device is used to heat the adsorbent regeneration tower, which saves energy, is green and environmentally friendly, absorbs the nitrogen oxides desorbed by heating into the alkali liquor adsorption device, and the adsorbent in the adsorbent regeneration tower can be reused after heating, which further reduces the cost of adsorbing nitrogen oxides.

[0012] According to some embodiments of the present application, a method for removing nitrogen oxides from flue gas is provided.

[0013] The flue gas generated by the boiler is introduced into the pre-cooler, and the pre-cooler is used to reduce the temperature of the flue gas to below 80℃.

[0014] The cooled flue gas is introduced into the water separator, and the cooled flue gas is dried.

[0015] The dried flue gas is introduced into the ozone adding point, the ozone adding point is used to introduce ozone into the flue gas and into the adsorption tower.

[0016] The flue gas adsorbed by the adsorption tower is introduced into the ozone removal device, and the ozone removal device is used to reduce and decompose the excess ozone in the flue gas.

[0017] Further, the adsorption tower is a fixed bed adsorption tower or a moving bed adsorption tower, and when the adsorption material in the adsorption tower is saturated and needs to be regenerated, if the fixed bed adsorption tower is used, the fixed bed adsorption tower is heated for regeneration; if the moving bed adsorption tower is used, the adsorption material in the moving bed adsorption tower is moved to the regeneration equipment for heating and regeneration.

[0018] Further, the dry flue gas is introduced into an ozone injection point, and the method further comprises: detecting the concentration of nitrogen monoxide and ozone in the flue gas entering the adsorption tower, and controlling the electromagnetic valve to make the volume ratio of the ozone and the nitrogen monoxide in the flue gas greater than 1:1.

[0019] Compared with the prior art, the present application has the following advantages:

[0020] (1) The ozone generator, ozone concentration detection sensor and electromagnetic valve are provided to ensure that the nitrogen oxides in the flue gas are completely oxidized, and the disproportionation reaction of nitrogen dioxide is effectively inhibited, so that the nitrogen oxides are zero-emission, the molecular sieve adsorbent is arranged in the adsorption tower to absorb the generated nitrogen dioxide, the molecular sieve has stable chemical properties, and the reaction between the ozone and the adsorbent can be prevented, the ozone removal device is connected to the gas outlet end of the adsorption tower, the active carbon is arranged in the ozone removal device to further adsorb a small amount of ozone, the secondary pollution caused by the ozone is effectively prevented, the problem of high cost caused by excessive ozone injection into the adsorption tower is avoided, the appropriate amount of ozone can inhibit the generation of nitrogen monoxide by the disproportionation reaction, the molecular sieve in the adsorption tower cannot reduce the ozone, the molecular sieve in the adsorption tower can fully adsorb the nitrogen oxides in the flue gas, the ozone removal device at the tail end reduces and decomposes the excess ozone, and the secondary pollution caused by the excess ozone in the flue gas discharged into the environment is avoided.

[0021] (2) The adsorption material in the adsorption tower of the device is the molecular sieve, the adsorption material can be heated and regenerated when the adsorption is saturated, and the operation cost of the device is reduced; the adsorption tower is a fixed bed adsorption tower or a moving bed adsorption tower, when the adsorption material in the adsorption tower is regenerated and used, if the fixed bed adsorption tower is used, the adsorption material in the fixed bed adsorption tower is heated and regenerated, if the moving bed adsorption tower is used, the adsorption material in the moving bed adsorption tower is moved to the regeneration equipment to be heated and regenerated, the nitrogen oxides in the flue gas and industrial waste gas of power plants, steel, metallurgy, chemical industry, cement and the like can be effectively removed, and the device has wide applicability.

[0022] (3) The adsorbent can be reused after being heated and regenerated, the nitrogen oxides desorbed by heating can be returned to the heating furnace for reduction treatment, or the nitrogen oxides desorbed by heating can be treated by alkali absorption or reduction by SCR, or the nitrogen oxides desorbed by heating can be made into nitric acid or nitrate products by resource utilization, the resource can be recycled, and the adsorption tower in the device can be a fixed bed adsorption tower or a moving bed adsorption tower according to actual conditions, and the device has wide applicability.

[0023] (4) By removing the motor driven cam rotation in the tower, so that the cam intermittent extrusion connecting plate and compression spring, driving the activated carbon mesh plate up and down reciprocating motion, activated carbon mesh plate and ozone molecules are in full contact, which is beneficial to the activated carbon mesh plate to reduce the decomposition of excess ozone, that is, to prevent the activated carbon caking, and to realize the activated carbon to the excess ozone completely reacted and absorbed to prevent the secondary pollution of ozone.

[0024] (5) The adsorbent regeneration tower is arranged in the industrial park, the nitrogen oxide adsorbent discharged from each adsorption tower in the industrial park is uniformly transported to the adsorbent regeneration tower centralized treatment point by a vehicle, heating regeneration is carried out, and the regenerated adsorbent is distributed to each adsorption device in the park for repeated use, so that the adsorbent regeneration efficiency is improved, and the adsorption cost is reduced.

[0025] Additional aspects and advantages of the application will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following description, or can be learned by practice of the application. BRIEF DESCRIPTION OF DRAWINGS

[0026] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor on the basis of these drawings.

[0027] Figure 1 is a flow diagram of a nitrogen oxide-containing flue gas adsorption and removal device and removal method according to the first embodiment of the present application;

[0028] Figure 2 is a structural diagram of an ozone removal device according to the embodiment of the present application;

[0029] Figure 3 is a device diagram of a nitrogen oxide-containing flue gas adsorption and removal device and removal method according to the second embodiment of the present application;

[0030] Figure 4 is another structural diagram of an ozone removal device according to the embodiment of the present application.

[0031] Reference signs:

[0032] 101, boiler; 102, booster fan; 103, air preheater; 104, dust remover;

[0033] 105, pre-cooler; 106, temperature sensor; 107, water separator; 1071, nitric oxide concentration sensor;

[0034] 108, ozone generating device; 1081, ozone concentration sensor; 1082, ozone dosing point;

[0035] 109, adsorption tower; 110, air extraction pump; 111, ozone removal device; 1111, activated carbon feeding channel;

[0036] 1112, filter screen; 1113, activated carbon discharging channel; 1114, activated carbon cavity; 1115, activated carbon screen plate;

[0037] 1116, through hole; 1117, limiting plate; 1118, cam mechanism; 1119, return spring; 1120, connecting plate;

[0038] 112, ozone detection device;

[0039] 113, adsorbent regeneration tower; 114, heat source input device; 115, lye adsorption device;

[0040] 116, regeneration heat source reflux device. DETAILED DESCRIPTION

[0041] The embodiments of the present application will be described in detail with reference to the drawings, and the embodiments described with reference to the drawings are exemplary, and it should be understood that the specific embodiments described herein are only used to explain the present application, and are not intended to limit the present application.

[0042] It should be noted that when an element is referred to as being "on" another element, it can be directly on the other element or intervening elements can also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements can also be present.

[0043] 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 application belongs. The terminology used in the description of the application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms "comprises", "comprising", "including" and "having" are intended to be inclusive and mean that there can be additional elements other than the listed elements.

[0044] Example 1

[0045] Referring to Figures 1 to 2 The present embodiment provides a nitrogen oxide-containing flue gas adsorption removal device and removal method, comprising:

[0046] The adsorption tower 109, the ozone generating device 108, the water removal separator 107, the pre-cooler 105 and the ozone removal device 111; the adsorption tower 109 is a moving bed adsorption tower, the gas inlet end of the adsorption tower 109 is connected with the water removal separator 107 and the ozone generating device 108 through a pipeline, the gas outlet end of the adsorption tower 109 is connected with the ozone removal device 111 through a pipeline, the gas inlet end of the water removal separator 107 is connected with the pre-cooler 105 through a pipeline, and the gas inlet end of the pre-cooler 105 is connected with the boiler 101 through a pipeline; wherein, the gas outlet end of the water removal separator 107 is provided with a nitrogen monoxide concentration sensor 1071, and the gas outlet end of the ozone generating device 108 is provided with an ozone concentration sensor 1081; the adsorption tower 109 is provided with a molecular sieve adsorbent.

[0047] The gas outlet end of the boiler 101 is further connected with a booster fan 102, an air preheater 103 and a dust remover 104 in sequence, and the gas outlet end of the dust remover 104 is connected with the pre-cooler 105; the booster fan 102 is arranged to guide the flue gas generated by the boiler 101 to the adsorption tower 109, the air preheater 103 is arranged to perform heat exchange between the flue gas and the air entering the boiler, so as to improve the heat utilization rate of the flue gas; the pre-cooler 105 is arranged to cool the flue gas to below 80℃, so as to avoid decomposition of ozone due to too high temperature of the flue gas; the air preheater 103 is arranged to perform heat exchange between the flue gas and the air entering the boiler 101, so as to improve the heat utilization rate of the flue gas;

[0048] The gas outlet pipeline of the ozone generating device 108 is further provided with a solenoid valve, the gas outlet end of the water removal separator 107 is provided with a nitrogen monoxide concentration sensor 1071 for monitoring the concentration of nitrogen monoxide in the flue gas at the gas inlet end of the adsorption tower 109, the gas outlet end of the ozone generating device 108 is provided with an ozone concentration sensor 1081 for monitoring the concentration of the output ozone, and the ozone generating device 108 controls the opening degree of the solenoid valve on the gas outlet pipeline, so that the volume ratio of ozone and nitrogen monoxide at the ozone adding point 1082 is greater than 1:1, under the volume ratio condition, nitrogen monoxide can be completely oxidized into nitrogen dioxide, and a small amount of excess ozone can inhibit the disproportionation reaction of nitrogen dioxide to regenerate nitrogen monoxide, and the molar ratio can ensure zero emission of nitrogen oxides while further reducing the consumption of ozone; the ozone is moderately excessive to inhibit the occurrence of disproportionation reaction.

[0049] It should be noted that in the adsorption tower 109, molecular sieve is used as adsorbent to adsorb nitrogen oxides in flue gas, so as to achieve the purpose of flue gas denitration; the outlet end of the pre-cooler 105 is provided with a temperature sensor 106; the pre-cooler 105 is used to cool the flue gas to below 80℃, so as to avoid decomposition of ozone due to too high temperature of flue gas; the water separator 107 is a cyclone type water separator, which is used to remove water in flue gas; it can be understood that, since the adsorbent adsorbs nitrogen oxides through pores, removal of water in flue gas can avoid the pores of the adsorbent being occupied by water, thereby reducing the adsorption capacity of the adsorbent for nitrogen oxides; at the same time, since the molecular sieve has stable chemical properties, it can prevent reaction of ozone with the adsorbent.

[0050] In an implementation, the ozone removal device 111 is provided with an air pump 110 at the inlet end, and is further provided with an ozone detection device 112 at the outlet end; the air pump 110 is used to guide the flow of flue gas adsorbed by the adsorption tower 109, the ozone removal device 111 is used to absorb excess ozone discharged, and the ozone detection device 112 is used to detect whether the ozone is completely absorbed; it should be noted that the ozone detection device 112 can also be used to judge the adsorption capacity of the adsorbent in the ozone removal device 111, so that the staff can replace the adsorbent in the ozone removal device 111 in time.

[0051] In the embodiment, the adsorption tower 109 is a moving bed type adsorption tower; in order to achieve green environmental protection and reduce the cost of adsorbing nitrogen oxide flue gas of the whole device, the adsorbent in the adsorption tower 109 can be regenerated by heating after saturation, so as to achieve recycling; the bottom of the adsorption tower 109 is connected with an adsorbent regeneration tower 113, and one end of the adsorbent regeneration tower 113 is connected with a heat source input device 114; the other end of the adsorbent regeneration tower 113 is connected with a regenerated heat source reflux device 116; it should be noted that the heat source input device 114 is used to guide hot oil or hot flue gas to heat the adsorbent regeneration tower 113.

[0052] In an implementation, the adsorbent regeneration tower 113 is connected with an alkali liquid adsorption device 115 through a pipeline; when the adsorbent saturated with adsorption material in the adsorbent regeneration tower 113 is heated, the nitrogen oxides adsorbed by the adsorbent are pyrolyzed and volatilized, and the nitrogen oxides volatilized by heating of the adsorbent are well absorbed and treated by the alkali liquid adsorption device 115; nitric acid or nitrate products are prepared to realize resource recycling; the adsorbent material after heating can be added into the adsorption tower 109 again.

[0053] As Figure 2As shown, the ozone removal device 111 is provided with a plurality of activated carbon mesh plates 1115, the two ends of the activated carbon mesh plate 1115 are slidably connected with the limiting plate 1117, and the two ends of the activated carbon mesh plate 1115 are connected with the bottom wall of the sliding groove of the limiting plate 1117 through the reset spring 1119, the limiting plate 1117 is installed on the inner wall of the ozone removal device 111, the activated carbon mesh plate 1115 is uniformly provided with through holes 1116, the activated carbon mesh plates 1115 are connected with the connecting plate 1120, the ozone removal device 111 is provided with a cam mechanism 1118, the cam mechanism 1118 abuts against the connecting plate 1120, when the flue gas containing nitrogen oxides is discharged from the adsorption tower 109 and enters the ozone removal device 111, the motor in the ozone removal device 111 drives the cam 1118 to rotate, the cam 1118 intermittently extrudes the connecting plate 1120 and compresses the reset spring 1119, drives the activated carbon mesh plate 1115 to reciprocate up and down, so that the activated carbon mesh plate 1115 is in full contact with ozone molecules, which is beneficial to the reduction and decomposition of excess ozone by the activated carbon mesh plate 1115, and avoids that the through holes 1116 provided on the activated carbon mesh plate 1115 are too large, so that the excess ozone does not fully contact with the activated carbon and is directly discharged from the ozone removal device 111.

[0054] The ozone generation device 111, the ozone concentration sensor 1081 and the electromagnetic valve ensure that the flue gas nitrogen oxides are completely oxidized, while effectively inhibiting the disproportionation reaction of nitrogen dioxide, realizing zero emission of nitrogen oxides, the molecular sieve adsorbent in the adsorption tower 109 absorbs the generated nitrogen dioxide, the molecular sieve has stable chemical properties, can prevent the reaction between ozone and the adsorbent, the ozone removal device 111 is connected to the gas outlet end of the adsorption tower 109, the ozone removal device 111 is provided with activated carbon for further adsorption of a small amount of ozone, effectively preventing secondary pollution caused by ozone, avoiding the problem of high cost caused by excessive ozone in the adsorption tower, and the appropriate amount of ozone can inhibit the generation of nitric oxide by the disproportionation reaction, while the molecular sieve in the adsorption tower will not reduce the ozone, which is beneficial to the full adsorption of nitrogen oxides in the flue gas by the molecular sieve in the adsorption tower, and the ozone removal device 111 at the tail reduces and decomposes the excess ozone, avoiding the secondary pollution caused by the excess ozone discharged into the environment through the flue gas.

[0055] Example 2

[0056] Please refer to Figures 2 to 3 The embodiment provides a nitrogen oxide-containing flue gas adsorption and removal device and a removal method, which comprises:

[0057] The adsorption tower 109, the ozone generating device 108, the water removal separator 107, the pre-cooler 105 and the ozone removal device 111; wherein the adsorption tower 109 is a fixed bed adsorption tower, the gas inlet end of the adsorption tower 109 is connected with the water removal separator 107 and the ozone generating device 108 through a pipeline, the gas outlet end of the adsorption tower 109 is connected with the ozone removal device 111 through a pipeline, the gas inlet end of the water removal separator 107 is connected with the pre-cooler 105 through a pipeline, and the gas inlet end of the pre-cooler 105 is connected with the boiler 101 through a pipeline; wherein the gas outlet end of the water removal separator 107 is provided with a nitrogen monoxide concentration sensor 1071, and the gas outlet end of the ozone generating device 108 is provided with an ozone concentration sensor 1081; the adsorption tower 109 is provided with a molecular sieve adsorbent,

[0058] The gas outlet end of the boiler 101 is further connected with the booster fan 102, the air preheater 103 and the dust remover 104 in sequence, and the gas outlet end of the dust remover 104 is connected with the pre-cooler 105; the booster fan 102 is arranged to guide the flue gas generated by the boiler 101 to the adsorption tower 109, the air preheater 103 is arranged to perform heat exchange between the flue gas and the air entering the boiler, so as to improve the heat utilization rate of the flue gas; the pre-cooler 105 is arranged to cool the flue gas to below 80 DEG C, so as to avoid decomposition of ozone due to too high temperature of the flue gas; the air preheater 103 is arranged to perform heat exchange between the flue gas and the air entering the boiler 101, so as to improve the heat utilization rate of the flue gas;

[0059] The gas outlet pipeline of the ozone generating device 108 is further provided with a solenoid valve, the gas outlet end of the water removal separator 107 is provided with a nitrogen monoxide concentration sensor 1071 for monitoring the concentration of nitrogen monoxide in the flue gas at the gas inlet end of the adsorption tower 109, the gas outlet end of the ozone generating device 108 is provided with an ozone concentration sensor 1081 for monitoring the concentration of the output ozone, and the opening degree of the solenoid valve on the gas outlet pipeline of the ozone generating device 108 is controlled, so that the volume ratio of ozone and nitrogen monoxide at the ozone adding point 1082 is greater than 1:1, under the volume ratio condition, nitrogen monoxide can be completely oxidized into nitrogen dioxide, and a small amount of excess ozone can inhibit the disproportionation reaction of nitrogen dioxide to regenerate nitrogen monoxide, and the molar ratio can ensure zero emission of nitrogen oxides while further reducing the consumption of ozone; the ozone is moderately excessive to inhibit the occurrence of disproportionation reaction.

[0060] It should be noted that, in the adsorption tower 109, molecular sieve is used as adsorbent to adsorb nitrogen oxides in flue gas, so as to achieve the purpose of flue gas denitration; the gas outlet end of the pre-cooler 105 is provided with a temperature sensor 106; the pre-cooler 105 is used to cool the flue gas to below 80℃, so as to avoid decomposition of ozone due to too high temperature of flue gas; the water separator 107 is a cyclone water separator, which is used to remove water in flue gas; it can be understood that, since the adsorbent adsorbs nitrogen oxides through pores, removal of water in flue gas can avoid the pores of the adsorbent being occupied by water in flue gas, so as to reduce the adsorption capacity of the adsorbent for nitrogen oxides; at the same time, since the molecular sieve has stable chemical properties, it can prevent reaction of ozone with the adsorbent.

[0061] In an implementation manner, the ozone removal device 111 is provided with an air pump 110 at the gas inlet end, and is further provided with an ozone detection device 112 at the gas outlet end; the air pump 110 is used to guide the flow of flue gas adsorbed by the adsorption tower 109, the ozone removal device 111 is used to absorb excess ozone discharged, and the ozone detection device 112 is used to detect whether the ozone is completely absorbed; it should be noted that the ozone detection device 112 can also be used to judge the adsorption capacity of the adsorbent in the ozone removal device 111, so that the staff can replace the adsorbent in the ozone removal device 111 in time.

[0062] In the embodiment, the adsorption tower 109 is a fixed bed adsorption tower; in order to realize reuse of the adsorbent and reduce the cost of adsorption of nitrogen oxide flue gas by the whole device, the adsorbent in the adsorption tower 109 can be regenerated by heating after saturation, so as to be reused; it should be noted that, when the adsorption tower 109 is a fixed bed adsorption tower, the adsorbent can be regenerated by heating directly in the adsorption tower; nitrogen oxides desorbed in the heating process can be returned to the heating furnace for reduction treatment; or treated by alkali absorption; or reduced by SCR; or made into nitric acid or nitrate product by resource utilization, which is conducive to recycling of resources.

[0063] As Figure 2As shown, the ozone removal device 111 is provided with a plurality of activated carbon mesh plates 1115, the two ends of the activated carbon mesh plate 1115 are slidably connected with the limiting plate 1117, and the two ends of the activated carbon mesh plate 1115 are connected with the bottom wall of the sliding groove of the limiting plate 1117 through the reset spring 1119, the limiting plate 1117 is installed on the inner wall of the ozone removal device 111, the activated carbon mesh plate 1115 is uniformly provided with through holes 1116, the activated carbon mesh plates 1115 are connected with the connecting plate 1120, the ozone removal device 111 is provided with a cam mechanism 1118, the cam mechanism 1118 abuts against the connecting plate 1120, when the flue gas for removing nitrogen oxides is discharged from the adsorption tower 109 and enters the ozone removal device 111, the motor in the ozone removal device 111 drives the cam 1118 to rotate, the cam 1118 intermittently extrudes the connecting plate 1120 and compresses the reset spring 1119, drives the activated carbon mesh plate 1115 to reciprocate up and down, so that the activated carbon mesh plate 1115 is in full contact with ozone molecules, which is beneficial to the reduction and decomposition of excess ozone by the activated carbon mesh plate 1115, and avoids that the excess ozone is directly discharged from the ozone removal device 111 without being in full contact with the activated carbon due to the through holes 1116 provided on the activated carbon mesh plate 1115 being too large.

[0064] The working principle of the embodiment is as follows: in specific use, the flue gas is discharged from the gas outlet end of the boiler 101, sequentially passes through the booster fan 102, the air preheater 103, the dust remover 104, the pre-cooler 105 and the water separator 107, reaches the ozone adding point 1082, the electromagnetic valve is further arranged on the gas outlet pipeline of the ozone generator 108, the nitrogen monoxide concentration sensor 1071 is arranged at the gas outlet end of the water separator 107 and is used for monitoring the concentration of nitrogen monoxide in the flue gas at the gas inlet end of the adsorption tower 109, the ozone concentration sensor 1081 installed at the gas outlet end of the ozone generator 108 is used for monitoring the concentration of the output ozone, the ozone generator 108 controls the opening degree of the electromagnetic valve on the gas outlet pipeline, so that the molar ratio of ozone to nitrogen monoxide at the ozone adding point 1082 is 1.2-1.5, after the flue gas enters the adsorption tower 109, the molecular sieve in the adsorption tower 109 adsorbs NO2 in the flue gas, after adsorption, the molecular sieve is discharged through the bottom end of the adsorption tower 206, at the same time, the excess ozone inhibits the occurrence of the nitrogen dioxide disproportionation reaction, finally, the flue gas for removing nitrogen oxides is discharged from the upper end of the adsorption tower 206, enters the ozone removal device 208, and the activated carbon in the ozone removal device 208 reduces and decomposes the excess ozone, avoiding the excess ozone from overflowing to the external environment

[0065] The ozone generator 111, ozone concentration sensor 1081 and electromagnetic valve are arranged to ensure that the flue gas nitrogen oxides are completely oxidized, while effectively inhibiting the dismutation reaction of nitrogen dioxide, achieving zero emission of nitrogen oxides. The molecular sieve adsorbent in the adsorption tower 109 absorbs the generated nitrogen dioxide. Since the molecular sieve has stable chemical properties, it can prevent the reaction of ozone and the adsorbent. The ozone removal device 111 is connected to the outlet end of the adsorption tower 109, and the ozone removal device 111 is provided with activated carbon to further adsorb a small amount of ozone, effectively preventing secondary pollution caused by ozone. The problem of excessive ozone being discharged into the adsorption tower to cause high costs is avoided. An appropriate amount of ozone can inhibit the production of nitric oxide by dismutation reaction, and the molecular sieve in the adsorption tower will not reduce ozone, which is conducive to the full adsorption of nitrogen oxides in the flue gas by the molecular sieve in the adsorption tower. The ozone removal device 111 at the tail reduces and decomposes excess ozone to avoid secondary pollution caused by excess ozone being discharged into the environment through the flue gas.

[0066] Embodiment 3

[0067] Please refer to Figure 4 , this embodiment is based on the above-mentioned embodiment, and describes an alternative ozone removal device 111, comprising:

[0068] The ozone removal device 111 is provided with a filter screen 1112, which is arranged along the wall of the activated carbon cavity 1114. The activated carbon cavity 1114 is filled with activated carbon. The top end of the ozone removal device 111 is provided with an activated carbon feeding channel 1111, and the bottom end is provided with an activated carbon discharging channel 1113. The activated carbon feeding channel 1111 and the activated carbon discharging channel 1113 are both provided with shut-off valves. It can be understood that activated carbon has strong reducing capacity and can reduce excess ozone in the flue gas discharged from the adsorption tower 109, avoiding the discharge of excess ozone into the environment through the flue gas to cause secondary pollution.

[0069] Embodiment 4

[0070] The embodiment provides a method for adsorbing and removing nitrogen oxide-containing flue gas, comprising:

[0071] The flue gas generated by the boiler is introduced into a pre-cooler, which reduces the temperature of the flue gas to below 80℃;

[0072] The cooled flue gas is introduced into a water removal separator for drying;

[0073] The dried flue gas is introduced into an ozone addition point, which introduces ozone into the flue gas and passes into the adsorption tower;

[0074] The flue gas after being adsorbed by the adsorption tower is introduced into an ozone removal device, and the ozone removal device reduces and decomposes the excess ozone in the flue gas.

[0075] In some embodiments, the adsorption tower is a fixed bed adsorption tower or a moving bed adsorption tower. When the adsorbed saturated adsorption material in the adsorption tower is regenerated and used, if the fixed bed adsorption tower is used, heating regeneration is performed in the fixed bed adsorption tower; if the moving bed adsorption tower is used, the adsorption material in the moving bed adsorption tower is moved to a regeneration device for heating regeneration.

[0076] In some embodiments, the concentration of nitrogen monoxide and the concentration of ozone in the flue gas introduced into the adsorption tower are detected, and the volume ratio of the ozone and the nitrogen monoxide in the flue gas is greater than 1:1 through the control of the electromagnetic valve.

[0077] The adsorption and removal method of the flue gas containing nitrogen oxides in the embodiment ensures that the nitrogen oxides in the flue gas are completely oxidized, effectively inhibits the dismutation reaction of nitrogen dioxide, realizes zero emission of nitrogen oxides, effectively prevents secondary pollution caused by ozone, avoids the problem of high cost caused by excessive ozone being put into the adsorption tower, the excess ozone is reduced and decomposed by the ozone removal device at the tail, and secondary pollution caused by the excess ozone being discharged into the environment through the flue gas is avoided.

[0078] In the embodiment, the adsorption material in the adsorption tower is a molecular sieve. When the adsorption material is saturated, the adsorption material can be regenerated by heating, thereby reducing the operation cost of the device. The adsorption tower is a fixed bed adsorption tower or a moving bed adsorption tower. When the adsorbed saturated adsorption material in the adsorption tower is regenerated and used, if the fixed bed adsorption tower is used, heating regeneration is performed in the fixed bed adsorption tower; if the moving bed adsorption tower is used, the adsorption material in the moving bed adsorption tower is moved to a regeneration device for heating regeneration. The nitrogen oxides in the flue gas and industrial waste gas in power plants, steel, metallurgy, chemical industry, cement industry and other industries can be effectively removed, and the applicability is wide.

[0079] In the embodiment, the nitrogen oxides desorbed by heating are returned to the heating furnace for flue gas reduction treatment, or are treated by alkali absorption, or are reduced by SCR, or are made into nitric acid or nitrate products by resource utilization, which is beneficial to the recycling of resources. In addition, the adsorption tower in the device can be a fixed bed adsorption tower or a moving bed adsorption tower according to the actual situation, and the adaptability is wide.

[0080] In the description of the application, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like are used to indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only used for the purpose of facilitating the description of the application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the application.

[0081] In the description of the application, the description of the terms "one embodiment", "some embodiments", "illustrative embodiment", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the application. In this specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example.

[0082] It is clear that the described embodiments are only a part of the embodiments of the application, not all the embodiments. In this paper, "embodiment" means that the specific features, structures or characteristics described in connection with the embodiment can be included in at least one embodiment of the application. The phrase appears at various places in the specification is not necessarily the same embodiment, nor is it independent or alternative to other embodiments or alternative embodiments. Those skilled in the art can explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the application.

[0083] Although embodiments of the application have been shown and described, those skilled in the art can understand that various changes, modifications, replacements and variations of the embodiments can be made without departing from the principles and spirit of the application, and the scope of the application is defined by the claims and their equivalents.

Claims

1. A nitrogen oxide-containing flue gas adsorptive removal device characterized by comprising: It includes: Adsorption tower (109), ozone generator (108), water separator (107), pre-cooler (105) and ozone removal device (111); the gas inlet end of the adsorption tower (109) is connected with the water separator (107) and the ozone generator (108) through a pipeline, the gas outlet end of the adsorption tower (109) is connected with the ozone removal device (111) through a pipeline, the gas inlet end of the water separator (107) is connected with the pre-cooler (105) through a pipeline, the gas inlet end of the pre-cooler (105) is connected with the boiler (101) through a pipeline, the gas outlet end of the water separator (107) is provided with a nitric oxide concentration sensor (1071), the gas outlet end of the ozone generator (108) is provided with an ozone concentration sensor (1081), wherein A plurality of activated carbon mesh plates (1115) are arranged at intervals in the ozone removal device (111), both ends of the activated carbon mesh plate (1115) are slidably connected with the limiting plate (1117), and both ends of the activated carbon mesh plate (1115) are connected with the bottom wall of the sliding groove formed in the limiting plate (1117) through the reset spring (1119), the limiting plate (1117) is installed on the inner wall of the ozone removal device (111), the activated carbon mesh plate (1115) is uniformly distributed with through holes (1116), the activated carbon mesh plates (1115) are connected with the connecting plate (1120), the ozone removal device (111) is provided with a cam mechanism (1118), and the cam mechanism (1118) abuts with the connecting plate (1120); The gas outlet end of the ozone removal device (111) is sequentially provided with an ozone detection device (112) and an electromagnetic valve, the gas outlet end of the boiler (101) is further sequentially connected with a booster fan (102), an air preheater (103) and a dust remover (104), the gas outlet end of the dust remover (104) is connected with the pre-cooler (105), and the gas outlet end of the pre-cooler (105) is provided with a temperature sensor (106); The gas outlet pipeline of the ozone generator (108) is further provided with an electromagnetic valve, the nitric oxide concentration sensor (1071) arranged at the gas outlet end of the water separator (107) is used for monitoring the concentration of nitric oxide in the flue gas at the gas inlet end of the adsorption tower (109), the ozone concentration sensor (1081) installed at the gas outlet end of the ozone generator (108) is used for monitoring the concentration of output ozone, and the opening degree of the electromagnetic valve on the gas outlet pipeline of the ozone generator (108) is controlled, so that the volume ratio of ozone to nitric oxide at the ozone dosing point (1082) is greater than 1:

1.

2. A device for removing nitrogen oxides from flue gases by adsorption according to claim 1, characterized in that: The bottom adsorbent outlet of the adsorption tower (109) is connected with an adsorbent regeneration tower (113), and the gas inlet end of the adsorbent regeneration tower (113) is connected with a heat source input device (114) through a pipeline.

3. A device for removing nitrogen oxides from flue gases by adsorption according to claim 2, characterized in that: The adsorbent regeneration tower (113) is connected with a lye adsorption device (115) through a pipeline, and the lye adsorption device (115) is used for absorbing and treating nitrogen oxides desorbed from the adsorbent by heating.

4. A method for the adsorptive removal of nitrogen oxide containing flue gases, characterized in that The method is applied to the nitrogen oxide-containing flue gas adsorption removal device as claimed in any one of claims 1-3 above, and the method comprises: introducing the flue gas generated by the boiler into a pre-cooler, which reduces the temperature of the flue gas to below 80℃; introducing the cooled flue gas into a water removal separator to dry the cooled flue gas; introducing the dried flue gas into an ozone injection point, which introduces ozone into the flue gas and passes the mixture into an adsorption tower; introducing the flue gas after adsorption in the adsorption tower into an ozone removal device, which reduces and decomposes the excess ozone in the flue gas.

5. A method for the removal of nitrogen oxides from flue gases by adsorption according to claim 4, characterized in that The method further comprises that the adsorption tower is a fixed bed adsorption tower or a moving bed adsorption tower, wherein, when the adsorbed saturated adsorption material in the adsorption tower is regenerated for use, if the fixed bed adsorption tower is used, heating regeneration is performed in the fixed bed adsorption tower; if the moving bed adsorption tower is used, the adsorption material in the moving bed adsorption tower is moved to a regeneration device for heating regeneration.

6. A method for the removal of nitrogen oxides from a flue gas by adsorption according to claim 5, characterized in that The introduction of the dried flue gas into the ozone injection point, which introduces ozone into the flue gas and passes the mixture into an adsorption tower, further comprises: detecting the concentration of nitrogen monoxide and the concentration of ozone in the flue gas passed into the adsorption tower, and controlling the electromagnetic valve to make the volume ratio of the ozone and the nitrogen monoxide in the flue gas greater than 1:1.

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