CN116099339A - A nitrogen oxide-containing flue gas adsorption and removal device and removal method - Google Patents

Abstract

The invention relates to the technical field of industrial waste gas removal treatment, and particularly discloses an adsorption removal device and a removal method for nitrogen oxide-containing flue gas; comprises an adsorption tower, an ozone generating device, a water removal separator, a precooler and an ozone removing device; the air inlet end of the adsorption tower is connected with a water removal separator and an ozone generating device through pipelines, the air outlet end of the adsorption tower is connected with an ozone removing device through pipelines, the air inlet end of the water removal separator is connected with a precooler through a pipeline, and the air inlet end of the precooler is communicated with a boiler through a pipeline; wherein, the air outlet end of the water separator is provided with a nitric oxide concentration sensor, and the air outlet end of the ozone generating device is provided with an ozone concentration sensor; a molecular sieve adsorbent is arranged in the adsorption tower; the molecular sieve adsorbent is arranged in the adsorption tower to absorb the generated nitrogen dioxide, so that zero emission of nitrogen oxides is realized, and the ozone removing device is connected with the air outlet end of the adsorption tower to adsorb redundant ozone, so that secondary pollution caused by ozone is effectively prevented.

Description

A nitrogen oxide-containing flue gas adsorption and removal device and removal method

technical field

The invention relates to the technical field of industrial waste gas removal and treatment, in particular to an adsorption and removal device and removal method for flue gas containing nitrogen oxides.

Background technique

Nitrogen oxides are one of the main pollutants in the atmosphere, mainly from fossil fuel combustion and exhaust gases from chemical fertilizers, pharmaceuticals, organic synthesis, metal smelting, electronics and other industries. Nitrogen oxides not only lead to the formation of acid rain, but also cause the formation of photochemical smog and the destruction of the ozone layer. In addition, if nitrogen oxides are inhaled into the human body, it will not only cause great damage to the nervous system, but also have a strong corrosive and stimulating effect on the respiratory system. Therefore, the control of nitrogen oxides has important social needs and practical significance.

The Chinese patent with the publication number CN110743312A and the publication date of 2020-02-04 discloses "a flue gas low-temperature adsorption denitrification system and process", which discloses a booster fan, a cooling recovery device, a flue gas cooling system, Flue gas switching valve and denitrification adsorption tower; among them, the inlet of the booster fan is connected with the inlet flue gas pipeline, and the booster fan, cooling recovery device, flue gas cooling system, flue gas switching valve and denitrification adsorption tower are connected in sequence, and the flue gas switching The outlets of the valve are respectively connected to the first denitrification adsorption tower and the second denitrification adsorption tower, the flue gas outlets of the first denitrification adsorption tower and the second denitrification adsorption tower are connected to the flue gas confluence, and the flue gas confluence is connected to the cooling recovery device; Adsorption and denitrification systems and processes realize the adsorption and removal of most nitrogen oxides. However, since the content of NO in flue gas NOx is the highest, and NO is a gas that is extremely difficult to adsorb, this prior art can absorb NO by introducing O2 NO is oxidized to NO2 for adsorption and removal, but due to the slow oxidation reaction of O2 and NO at low temperature, the content of NO in the flue gas is high, and the adsorbed NO2 is prone to disproportionation reaction, resulting in the regeneration of NO, so in the actual adsorption and removal During the process, the adsorption and denitrification system and process cannot adsorb and remove nitrogen oxides with high efficiency, which may easily cause secondary pollution emissions.

In the prior art, the ozone ion plasma oxidation method in the pre-oxidation method is used. In order to ensure that the flue gas NOx is completely oxidized, a large amount of ozone is often introduced, resulting in high ozone usage costs, and the excess ozone introduced is directly discharged. If it is not effectively removed, it is easy to cause secondary pollution discharge.

Contents of the invention

The present invention aims to solve at least one of the technical problems existing in the prior art. Therefore, the present invention proposes an adsorption and removal device and removal method for flue gas containing nitrogen oxides.

A nitrogen oxide-containing flue gas adsorption and removal device and removal method according to the embodiment of the first aspect of the present invention, comprising:

Adsorption tower, ozone generating device, dehydration separator, precooler and ozone removal device; the inlet end of the adsorption tower is connected to the dehydration separator and the ozone generating device through pipelines, and the gas outlet end of the adsorption tower An ozone removal device is connected through a pipeline, the inlet end of the dehydration separator is connected to the precooler through a pipeline, and the inlet end of the precooler is connected to the boiler through a pipeline; wherein, the gas outlet of the dehydration separator A nitric oxide concentration sensor is provided at the end, and an ozone concentration sensor is provided at the gas outlet of the ozone generating device;

Wherein, a plurality of activated carbon mesh plates are arranged at intervals in the ozone removal device, and the two ends of the activated carbon mesh plates are slidingly connected with the limit plate, and the two ends of the activated carbon mesh plate are opened with the limit plate through a return spring. The bottom wall of the chute is connected, the limit plate is installed on the inner wall of the ozone removal device, through holes are evenly distributed on the activated carbon mesh plate, connecting plates are connected between the activated carbon mesh plates, the The ozone removal device is provided with a cam, and the cam abuts against the connecting plate.

According to a nitrogen oxide-containing flue gas adsorption and removal device and removal method according to an embodiment of the present invention, the ozone generated by the ozone generator is passed into the nitrogen oxide-containing flue gas. Due to the strong oxidizing property of ozone, the Nitric oxide is oxidized to nitrogen dioxide, the data is measured by the nitric oxide concentration sensor and the ozone concentration sensor, and then the opening of the solenoid valve is controlled to control the molar ratio between nitric oxide oxidation and ozone, so that the nitric oxide can be completely oxidized into Nitrogen dioxide, because a small amount of ozone can inhibit the disproportionation reaction of nitrogen dioxide to regenerate nitrogen monoxide, and at the same time, the molar ratio can further reduce the consumption of ozone while ensuring zero emission of nitrogen oxides; through the adsorption tower Molecular sieve adsorbent is installed to absorb the generated nitrogen dioxide. Due to the stable chemical properties of molecular sieve, the reaction between ozone and adsorbent can be prevented. By connecting the ozone removal device at the outlet end of the adsorption tower, the ozone removal device is equipped with an activated carbon screen , There are return springs at both ends of the activated carbon mesh plate, and the cam mechanism drives the activated carbon mesh plate to reciprocate, which can prevent the activated carbon from agglomerating and realize the complete reaction and absorption of the excess ozone by the activated carbon, effectively preventing the secondary pollution of ozone.

According to some embodiments of the present invention, the gas outlet of the boiler is also connected to a booster fan, an air preheater, and a dust collector in sequence, and the gas outlet of the dust collector is connected to the precooler; the gas outlet of the precooler A temperature sensor is provided at the end of the ozone generating device, and a solenoid valve is provided in the outlet pipe of the ozone generator; by setting a booster fan, the flue gas generated by the boiler is guided to flow to the adsorption tower, and the air preheater is set for the flue gas and the air entering the boiler Carry out heat exchange to improve the heat utilization rate in the flue gas; use the pre-cooler to cool the flue gas below 80°C to avoid ozone decomposition caused by excessive flue gas temperature;

According to some embodiments of the present invention, the adsorbent outlet at the bottom of the adsorption tower is connected to an adsorbent regeneration tower, the inlet end of the adsorbent regeneration tower is connected to a heat source input device through a pipeline, and the adsorbent regeneration tower is connected to The lye adsorption device, the lye adsorption device is used to absorb and process the nitrogen oxides desorbed by the adsorbent through heating; the high-temperature flue gas guided by the heat source input device heats the adsorbent regeneration tower, which saves energy and is environmentally friendly. The adsorbed nitrogen oxides are desorbed by heating and passed to the alkali liquor adsorption device for absorption. At the same time, the adsorbent can be reused after being heated in the adsorbent regeneration tower. This setting further reduces the cost of adsorbing nitrogen oxides by the device.

A method for adsorption and removal of flue gas containing nitrogen oxides according to the embodiment of the second aspect of the present invention, the method includes:

The flue gas produced by the boiler is introduced into the pre-cooler, and the pre-cooler reduces the temperature of the flue gas to below 80°C;

Introducing the cooled flue gas into the water separator to dry the cooled flue gas;

The dried flue gas is introduced to the ozone dosing point, and the ozone dosing point is introduced into the adsorption tower to mix with the flue gas;

The flue gas adsorbed by the adsorption tower is introduced into the ozone removal device, and the ozone removal device reduces and decomposes excess ozone in the flue gas.

A further solution is that the adsorption tower adopts a fixed bed type adsorption tower or a moving bed type adsorption tower, wherein, when the adsorption material saturated in the adsorption tower is regenerated, if a fixed bed type adsorption tower is used, then in the Heating regeneration is carried out in the fixed bed type adsorption tower mentioned above; if a moving bed type adsorption tower is used, the adsorption material in the moving bed type adsorption tower is moved to the regeneration equipment for heating and regeneration.

A further solution is that the method of introducing the dried flue gas into the ozone dosing point, introducing ozone and the flue gas into the adsorption tower at the ozone dosing point also includes: The nitric oxide concentration and ozone concentration in the gas are detected, and the volume ratio of the ozone and the nitric oxide in the flue gas is greater than 1:1 through the control of the solenoid valve.

Compared with prior art, the beneficial effect of the present invention is:

(1) The present invention ensures that the flue gas nitrogen oxides are completely oxidized through the arrangement of the ozone generating device, the ozone concentration detection sensor and the solenoid valve, and effectively inhibits the disproportionation reaction of nitrogen dioxide at the same time, realizing zero discharge of nitrogen oxides. Molecular sieve adsorbent is installed inside to absorb the generated nitrogen dioxide. Due to the stable chemical properties of molecular sieve, it can prevent the reaction between ozone and adsorbent. By connecting the ozone removal device at the outlet end of the adsorption tower, the ozone removal device is equipped with activated carbon for further adsorption. A small amount of ozone can effectively prevent the secondary pollution caused by ozone, and avoid the problem of high cost caused by putting too much ozone into the adsorption tower. An appropriate amount of ozone can inhibit the disproportionation reaction to produce nitric oxide, and the molecular sieve in the adsorption tower will not remove ozone Reduction is beneficial to the molecular sieve in the adsorption tower to fully absorb nitrogen oxides in the flue gas, and the ozone removal device at the tail will reduce and decompose the excess ozone to avoid secondary pollution caused by excess ozone being discharged into the environment through the flue gas;

(2) The adsorption material in the adsorption tower of the device of the present invention is a molecular sieve. After the adsorption is saturated, the adsorption material can be heated and regenerated to reduce the operating cost of the device; the adsorption tower adopts a fixed bed type adsorption tower or a moving bed type adsorption tower , when the adsorption material saturated in the adsorption tower is used for regeneration, if a fixed bed adsorption tower is used, then heating and regeneration is carried out in the fixed bed adsorption tower; if a moving bed adsorption tower is used, the moving bed The adsorption material in the type adsorption tower is moved to the regeneration equipment for heating and regeneration; it can effectively remove the nitrogen oxides in the flue gas and industrial waste gas of power plants, steel, metallurgy, chemical industry, cement and other industries, and has wide applicability.

(3) The adsorbent of the present invention can be reused after being heated and regenerated, and the nitrogen oxides that are desorbed by heating are returned to the heating furnace for back-burning reduction treatment; or through lye absorption treatment; or through SCR for reduction treatment; or Nitric acid or nitrate products are produced through resource utilization, which is conducive to the repeated recycling of resources, and the adsorption tower in the device of the present invention can be a fixed bed adsorption tower or a moving bed adsorption tower according to the actual situation, which has wide adaptability .

(4) The motor in the removal tower drives the cam to rotate, so that the cam intermittently squeezes the connecting plate and compresses the spring, which drives the activated carbon screen to reciprocate up and down, and the activated carbon screen is in full contact with the ozone molecules, which is beneficial to the activated carbon screen. The reduction and decomposition of ozone can prevent the agglomeration of activated carbon, and realize the complete reaction and absorption of excess ozone by activated carbon, effectively preventing the secondary pollution of ozone.

(5) Set up adsorbent regeneration towers in the industrial park, and the nitrogen oxide adsorbents discharged from each adsorption tower in the industrial park are uniformly transported by vehicles to the centralized treatment point of the adsorbent regeneration towers for heating and regeneration, and the regenerated adsorbents are distributed to each of the park The repeated use of the adsorption device improves the regeneration efficiency of the adsorbent and reduces the adsorption cost.

Additional aspects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.

Description of drawings

In order to illustrate the technical solutions of the embodiments of the present invention more clearly, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. Those of ordinary skill in the art can also obtain other drawings based on these drawings without any creative effort.

Fig. 1 is a schematic flow diagram of a device for adsorption and removal of flue gas containing nitrogen oxides and a removal method according to the first embodiment of the present invention;

Fig. 2 is a schematic structural view of an ozone removal device provided according to an embodiment of the present invention;

Fig. 3 is a device schematic diagram of a nitrogen oxide-containing flue gas adsorption and removal device and removal method according to the second embodiment of the present invention;

Fig. 4 is another structural schematic diagram of an ozone removal device provided according to an embodiment of the present invention;

Reference signs:

101. Boiler; 102. Booster fan; 103. Air preheater; 104. Dust collector;

105. Precooler; 106. Temperature sensor; 107. Water separator; 1071. Nitric oxide concentration sensor;

108. Ozone generator; 1081. Ozone concentration sensor; 1082. Ozone dosing point;

109. Adsorption tower; 110. Air pump; 111. Ozone removal device; 1111. Activated carbon feed channel;

1112, filter screen; 1113, activated carbon discharge channel; 1114, activated carbon cavity; 1115, activated carbon screen;

1116, through hole; 1117, limit plate; 1118, cam mechanism; 1119, return spring; 1120, connecting plate;

112. Ozone detection device;

113. Adsorbent regeneration tower; 114. Heat source input device; 115. Alkaline adsorption device;

116. Regeneration heat source reflux device.

Detailed ways

Embodiments of the present invention are described in detail below, and the embodiments described with reference to the accompanying drawings are exemplary, and it should be understood that the specific embodiments described here are only used to explain the present application, and are not intended to limit the present application.

It should be noted that when an element is referred to as being “fixed” to another element, it can be directly on the other element or there can also be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or intervening elements may also be present.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field of the invention. The terminology used herein in the description of the present invention is only for the purpose of describing specific embodiments, and is not intended to limit the present invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

Example 1

Please refer to Fig. 1 to Fig. 2, this embodiment provides a nitrogen oxide-containing flue gas adsorption and removal device and removal method, including:

Adsorption tower 109, ozone generating device 108, dehydration separator 107, precooler 105 and ozone removal device 111; Described adsorption tower 109 is moving bed type adsorption tower, and described adsorption tower 109 inlet ends are connected by pipeline The dehydration separator 107 and the ozone generating device 108, the outlet end of the adsorption tower 109 is connected with the ozone removal device 108 through a pipeline, and the inlet end of the dehydration separator 107 is connected with the precooler 105 through a pipeline , the inlet end of the precooler 105 is connected to the boiler 101 through a pipeline; wherein, the outlet end of the dehydration separator 107 is provided with a nitric oxide concentration sensor 1071, and the outlet end of the ozone generator 108 is provided with an ozone concentration sensor 1081 ; The adsorption tower 109 is provided with a molecular sieve adsorbent.

The gas outlet of the boiler 101 is also connected to the booster fan 102, the air preheater 103 and the dust collector 104 in turn, and the gas outlet of the dust collector 104 is connected to the precooler 105; Guide the flue gas produced by the boiler 101 to flow to the adsorption tower 109, and set it through the air preheater 103 for heat exchange between the flue gas and the air entering the boiler to improve the heat utilization rate in the flue gas; The pre-cooler 105 is set to cool the flue gas below 80°C to avoid ozone decomposition caused by excessive flue gas; the air pre-cooler 102 is used for heat exchange between the flue gas and the air entering the boiler 101, improving Heat utilization rate in flue gas;

The outlet pipeline of the ozone generator 108 is also provided with a solenoid valve, and the outlet end of the dehydration separator 107 is provided with a nitric oxide concentration sensor 109 for monitoring a concentration in the flue gas at the inlet end of the adsorption tower 109. The concentration of nitrogen oxides, the ozone concentration sensor 1081 installed at the outlet of the ozone generator 108 is used to monitor the concentration of the output ozone, and the ozone generator 107 controls the opening of the electromagnetic valve on the outlet pipeline so that the ozone dosing point is 1082 The volume ratio of ozone and nitric oxide is greater than 1:1. Under this volume ratio, nitric oxide can be completely oxidized to nitrogen dioxide, and a small amount of ozone can inhibit the disproportionation reaction of nitrogen dioxide to regenerate At the same time, the molar ratio can further reduce the consumption of ozone while ensuring zero emission of nitrogen oxides; keep an appropriate excess of ozone to inhibit the occurrence of disproportionation reaction.

It should be noted that in the adsorption tower 109, molecular sieves are used as an adsorbent to adsorb nitrogen oxides in the flue gas, thereby achieving the purpose of flue gas denitrification; the outlet end of the precooler 105 is provided with a temperature sensor 106 ; The precooler 105 is used to cool the flue gas to below 80°C, so as to avoid ozone decomposition caused by excessive flue gas temperature; the water removal separator 107 is a cyclone type water removal separator, and the water removal separator 107 is used to remove Moisture in the flue gas, it can be understood that since the adsorbent adsorbs nitrogen oxides through the pores, removing the moisture in the flue gas can prevent the moisture in the flue gas from occupying the pores of the adsorbent and causing the adsorbent to adsorb nitrogen oxides At the same time, due to the stable chemical properties of molecular sieves, the reaction between ozone and adsorbents can be prevented;

In one possible implementation, the air intake end of the ozone removal device 111 is provided with an air suction pump 110, and the air outlet end of the ozone removal device 111 is also provided with an ozone detection device 112; the air suction pump 110 is used to guide the The adsorption tower 109 absorbs the flue gas flow direction, the ozone removal device 111 is used to absorb excess discharged ozone, 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 The 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.

In this embodiment, the adsorption tower 109 is a moving bed adsorption tower. In order to achieve environmental protection and reduce the cost of nitrogen oxide flue gas adsorption of the entire device, after the adsorbent in the adsorption tower 109 is saturated Heating and regeneration can be carried out to achieve reuse. The adsorbent outlet at the bottom of the adsorption tower 109 is connected to an adsorbent regeneration tower 113, and one end of the adsorbent regeneration tower 113 is connected to a heat source input device 114; the other end of the adsorbent regeneration tower 113 is A heat source output device 116 is connected. It should be noted that the heat source input device 114 guides heat transfer oil or hot flue gas to heat the adsorbent regeneration tower 113;

In a practicable manner, the adsorbent regeneration tower 113 is connected to the alkali liquor adsorption device 115 through a pipeline, and when the adsorbent saturated in the adsorbent regeneration tower 113 is heated, the nitrogen oxides adsorbed by the adsorbent Carry out pyrolysis and volatilization, and set up the nitrogen oxides desorbed by the adsorbent through heating through the lye adsorption device 115; make nitric acid or nitrate products to realize resource recycling, and the adsorbent materials can be re-added after heating In the adsorption tower 109.

As shown in Figure 2, several activated carbon mesh plates 1115 are arranged at intervals in the ozone removal device 111, and the two ends of the activated carbon mesh plates 1115 are slidingly connected with the limit plate 1117, and the two ends of the activated carbon mesh plates 1115 are reset The spring 1119 is connected with the bottom wall of the chute provided on the limiting plate 1117, the limiting plate 1117 is installed on the inner wall of the ozone removal device 111, and through holes 1116 are evenly distributed on the activated carbon mesh plate 1115 , the connecting plate 1120 is connected between the activated carbon mesh plates 1115, the ozone removal device 111 is provided with a cam mechanism 1118, and the cam mechanism 1118 abuts against the connecting plate 1120, when removing nitrogen oxide smoke The gas 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, and the cam 1118 intermittently squeezes the connecting plate 1120 and compresses the return spring 1119 to drive the activated carbon. The mesh plate 1115 reciprocates up and down, so that the activated carbon mesh plate 1115 is in full contact with the ozone molecules, which is beneficial to the activated carbon mesh plate 1115 to reduce and decompose excess ozone, and avoid excess ozone due to the large through hole 1116 opened on the activated carbon mesh plate 1115. It is directly discharged from the ozone removal device 111 without being in sufficient contact with the activated carbon.

The ozone generator 111, the ozone concentration sensor 1081 and the electromagnetic valve are set to ensure that the nitrogen oxides in the flue gas are completely oxidized, and at the same time effectively inhibit the disproportionation reaction of nitrogen dioxide, and realize zero emission of nitrogen oxides. Molecular sieves are installed in the adsorption tower 109 The adsorbent absorbs the generated nitrogen dioxide. Because the molecular sieve has stable chemical properties, it can prevent the reaction between ozone and the adsorbent. By connecting the ozone removal device 111 at the outlet of the adsorption tower 109, the ozone removal device 111 is equipped with activated carbon for further adsorption. A small amount of ozone can effectively prevent the secondary pollution caused by ozone, and avoid the problem of high cost caused by putting too much ozone into the adsorption tower. An appropriate amount of ozone can inhibit the disproportionation reaction to produce nitric oxide, and the molecular sieve in the adsorption tower will not remove ozone Reduction is beneficial to the molecular sieve in the adsorption tower to fully absorb the nitrogen oxides in the flue gas, and the ozone removal device 111 at the tail will reduce and decompose the excess ozone to avoid secondary pollution caused by the excess ozone being discharged into the environment through the flue gas .

Example 2

Please refer to Fig. 2 to Fig. 3, this embodiment provides a nitrogen oxide-containing flue gas adsorption and removal device and removal method, including:

Adsorption tower 109, ozone generator 108, dehydration separator 107, precooler 105 and ozone removal device 111; Connect the dehydration separator 107 and the ozone generating device 108, the outlet end of the adsorption tower 109 is connected with the ozone removal device 108 through a pipeline, and the inlet end of the dehydration separator 107 is connected with the precooling device through a pipeline. device 105, the inlet end of the precooler 105 is connected to the boiler 101 through a pipeline; wherein, the outlet end of the dehydration separator 107 is provided with a nitric oxide concentration sensor 1071, and the outlet end of the ozone generator 108 is provided with an ozone concentration Sensor 1081; molecular sieve adsorbent is arranged in the adsorption tower 109,

The gas outlet of the boiler 101 is also connected to the booster fan 102, the air preheater 103 and the dust collector 104 in turn, and the gas outlet of the dust collector 104 is connected to the precooler 105; Guide the flue gas produced by the boiler 101 to flow to the adsorption tower 109, and set it through the air preheater 103 for heat exchange between the flue gas and the air entering the boiler to improve the heat utilization rate in the flue gas; The pre-cooler 105 is set to cool the flue gas below 80°C to avoid ozone decomposition caused by excessive flue gas; the air pre-cooler 102 is used for heat exchange between the flue gas and the air entering the boiler 101, improving Heat utilization rate in flue gas;

The outlet pipeline of the ozone generator 108 is also provided with a solenoid valve, and the outlet end of the dehydration separator 107 is provided with a nitric oxide concentration sensor 109 for monitoring a concentration in the flue gas at the inlet end of the adsorption tower 109. The concentration of nitrogen oxides, the ozone concentration sensor 1081 installed at the outlet of the ozone generator 108 is used to monitor the concentration of the output ozone, and the ozone generator 107 controls the opening of the electromagnetic valve on the outlet pipeline so that the ozone dosing point is 1082 The volume ratio of ozone and nitric oxide is greater than 1:1. Under this volume ratio, nitric oxide can be completely oxidized to nitrogen dioxide, and a small amount of ozone can inhibit the disproportionation reaction of nitrogen dioxide to regenerate At the same time, the molar ratio can further reduce the consumption of ozone while ensuring zero emission of nitrogen oxides; keep an appropriate excess of ozone to inhibit the occurrence of disproportionation reaction.

It should be noted that in the adsorption tower 109, molecular sieves are used as an adsorbent to adsorb nitrogen oxides in the flue gas, thereby achieving the purpose of flue gas denitrification; the outlet end of the precooler 105 is provided with a temperature sensor 106 ; The precooler 105 is used to cool the flue gas to below 80°C, so as to avoid ozone decomposition caused by excessive flue gas temperature; the water removal separator 107 is a cyclone type water removal separator, and the water removal separator 107 is used to remove Moisture in the flue gas, it can be understood that since the adsorbent adsorbs nitrogen oxides through the pores, removing the moisture in the flue gas can prevent the moisture in the flue gas from occupying the pores of the adsorbent and causing the adsorbent to adsorb nitrogen oxides At the same time, due to the stable chemical properties of molecular sieves, the reaction between ozone and adsorbents can be prevented;

In one possible implementation, the air intake end of the ozone removal device 111 is provided with an air suction pump 110, and the air outlet end of the ozone removal device 111 is also provided with an ozone detection device 112; the air suction pump 110 is used to guide the The adsorption tower 109 absorbs the flue gas flow direction, the ozone removal device 111 is used to absorb excess discharged ozone, 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 The 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.

In this embodiment, the adsorption tower 109 is a fixed-bed adsorption tower. For a fixed-bed adsorption tower, in order to realize the reuse of adsorbents and reduce the cost of nitrogen oxide flue gas adsorption of the entire device, the adsorption tower The adsorbent in 109 can be heated and regenerated after being adsorbed and saturated to achieve reuse. It should be noted that when the adsorption tower 109 is a fixed-bed adsorption tower, it can be directly heated and regenerated in the adsorption tower, and the desorbed during the heating process Nitrogen oxides are treated by returning to the heating furnace for backburning reduction; or by lye absorption treatment; or by SCR for reduction treatment; or by resource utilization to make nitric acid or nitrate products, which is conducive to the repeated use of resources .

As shown in Figure 2, several activated carbon mesh plates 1115 are arranged at intervals in the ozone removal device 111, and the two ends of the activated carbon mesh plates 1115 are slidingly connected with the limit plate 1117, and the two ends of the activated carbon mesh plates 1115 are reset The spring 1119 is connected with the bottom wall of the chute provided on the limiting plate 1117, the limiting plate 1117 is installed on the inner wall of the ozone removal device 111, and through holes 1116 are evenly distributed on the activated carbon mesh plate 1115 , the connecting plate 1120 is connected between the activated carbon mesh plates 1115, the ozone removal device 111 is provided with a cam mechanism 1118, and the cam mechanism 1118 abuts against the connecting plate 1120, when removing nitrogen oxide smoke The gas 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, and the cam 1118 intermittently squeezes the connecting plate 1120 and compresses the return spring 1119 to drive the activated carbon. The mesh plate 1115 reciprocates up and down, so that the activated carbon mesh plate 1115 is in full contact with the ozone molecules, which is beneficial to the activated carbon mesh plate 1115 to reduce and decompose excess ozone, and avoid excess ozone due to the large through hole 1116 opened on the activated carbon mesh plate 1115. It is directly discharged from the ozone removal device 111 without being in sufficient contact with the activated carbon.

The working principle of this embodiment is: during specific use, the flue gas is discharged from the gas outlet of the boiler 101, and then arrives at Ozone dosing point 1082, the outlet pipe of ozone generating device 108 is also provided with a solenoid valve, and the outlet end of water separator 107 is provided with a nitric oxide concentration sensor 1071 for monitoring the concentration of nitric oxide in the intake end of adsorption tower 109. The concentration of nitrogen oxides, the ozone concentration sensor 1081 installed at the gas outlet of the ozone generating device 108 is used to monitor the concentration of the output ozone, and the ozone generating device 107 controls the opening of the electromagnetic valve on the gas outlet pipeline, so that the ozone at the ozone dosing point 1082 and a The molar ratio of nitrogen oxides is 1.2 to 1.5. After the flue gas enters the adsorption tower 109, the molecular sieve in the adsorption tower 109 absorbs NO2 in the flue gas. The generation of disproportionation reaction, the flue gas that finally removes nitrogen oxides is discharged from the upper end of adsorption tower 206, enters ozone removal device 208, and the activated carbon in ozone removal device 208 reduces and decomposes excess ozone, avoids excess ozone overflowing to external environment

The ozone generator 111, the ozone concentration sensor 1081 and the electromagnetic valve are set to ensure that the nitrogen oxides in the flue gas are completely oxidized, and at the same time effectively inhibit the disproportionation reaction of nitrogen dioxide, and realize zero emission of nitrogen oxides. Molecular sieves are installed in the adsorption tower 109 The adsorbent absorbs the generated nitrogen dioxide. Because the molecular sieve has stable chemical properties, it can prevent the reaction between ozone and the adsorbent. By connecting the ozone removal device 111 at the outlet of the adsorption tower 109, the ozone removal device 111 is equipped with activated carbon for further adsorption. A small amount of ozone can effectively prevent the secondary pollution caused by ozone, and avoid the problem of high cost caused by putting too much ozone into the adsorption tower. An appropriate amount of ozone can inhibit the disproportionation reaction to produce nitric oxide, and the molecular sieve in the adsorption tower will not remove ozone Reduction is beneficial to the molecular sieve in the adsorption tower to fully absorb the nitrogen oxides in the flue gas, and the ozone removal device 111 at the tail will reduce and decompose the excess ozone to avoid secondary pollution caused by the excess ozone being discharged into the environment through the flue gas .

Example 3

Referring to Fig. 4, this embodiment describes an alternative ozone removal device 111 on the basis of the above embodiments, including:

Described ozone removal device 111 is provided with filter screen 1112, and described filter screen 1112 is arranged along described activated carbon chamber 1114 cavity wall, and described activated carbon chamber 1114 is filled with activated carbon, and described ozone removal device 111 top is provided with The activated carbon feed channel 1111, the bottom end of the ozone removal device is provided with an activated carbon discharge channel 1113, and the activated carbon feed channel 1111 and the activated carbon discharge channel 1113 are both provided with shut-off valves. It can be understood that activated carbon has a strong reducing ability, and can reduce excess ozone in the flue gas discharged from the adsorption tower 109, so as to avoid secondary pollution caused by excess ozone being discharged into the environment through the flue gas.

Example 4

This embodiment provides a method for adsorption and removal of flue gas containing nitrogen oxides, the method comprising:

The flue gas produced by the boiler is introduced into the pre-cooler, and the pre-cooler reduces the temperature of the flue gas to below 80°C;

Introducing the cooled flue gas into the water separator to dry the cooled flue gas;

The dried flue gas is introduced to the ozone dosing point, and the ozone dosing point is introduced into the adsorption tower to mix with the flue gas;

introducing the flue gas adsorbed by the adsorption tower into an ozone removal device, and the ozone removal device reduces and decomposes excess ozone in the flue gas;

In some embodiments, the adsorption tower adopts a fixed bed type adsorption tower or a moving bed type adsorption tower, wherein, when the adsorption material saturated in the adsorption tower is used for regeneration, if a fixed bed type adsorption tower is used, then The fixed bed type adsorption tower is heated and regenerated; if the moving bed type adsorption tower is used, the adsorption material in the moving bed type adsorption tower is moved to the regeneration equipment for heating and regeneration.

In some embodiments, the nitric oxide concentration and the ozone concentration in the flue gas passing through the adsorption tower are detected, and the volume ratio of the ozone and the nitric oxide in the flue gas is greater than 1 through the control of the solenoid valve: 1.

Through the adsorption and removal method of flue gas containing nitrogen oxides in this embodiment, the complete oxidation of nitrogen oxides in flue gas is ensured, and at the same time, the disproportionation reaction of nitrogen dioxide is effectively inhibited, zero emission of nitrogen oxides is realized, and ozone generation is effectively prevented. Secondary pollution, avoiding the problem of high cost caused by putting too much ozone into the adsorption tower, the ozone removal device at the end will reduce and decompose the excess ozone, and avoid secondary pollution caused by the excess ozone being discharged into the environment through flue gas .

In this embodiment, the adsorption material in the adsorption tower is a molecular sieve. When the adsorption is saturated, the adsorption material can be heated and regenerated to reduce the operating cost of the device; the adsorption tower adopts a fixed bed adsorption tower or a moving bed adsorption tower , when the adsorption material saturated in the adsorption tower is used for regeneration, if a fixed bed adsorption tower is used, then heating and regeneration is carried out in the fixed bed adsorption tower; if a moving bed adsorption tower is used, the moving bed The adsorption material in the type adsorption tower is moved to the regeneration equipment for heating and regeneration; it can effectively remove the nitrogen oxides in the flue gas and industrial waste gas of power plants, steel, metallurgy, chemical industry, cement and other industries, and has wide applicability.

In this embodiment, the nitrogen oxides desorbed by heating are returned to the heating furnace for flashback reduction treatment; or through lye absorption treatment; or through SCR for reduction treatment; or through resource utilization to make nitric acid or The nitrate product is conducive to the repeated recycling of resources, and the adsorption tower in the device of the present invention can adopt a fixed bed type adsorption tower or a moving bed type adsorption tower according to the actual situation, and its adaptability is wide.

In describing the present invention, 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 other indicated orientations or positional relationships are based on the orientations or positional relationships shown in the drawings, which are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying the referred device or Elements must have certain orientations, be constructed and operate in certain orientations, and thus should not be construed as limitations on the invention.

In the description of this specification, references to the terms "one embodiment," "some embodiments," "exemplary embodiments," "example," "specific examples," or "some examples" are intended to mean that the implementation A specific feature, structure, material, or characteristic described by an embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example.

Apparently, the described embodiments are only some of the embodiments of this application, not all of them. Reference herein to an "embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the present application of the embodiments. The occurrences of this phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. It is understood explicitly and implicitly by those skilled in the art that the embodiments described herein can be combined with other embodiments. Based on the embodiments in this application, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the scope of protection of this application.

Although the embodiments of the present invention have been shown and described, those skilled in the art can understand that various changes, modifications, substitutions and modifications can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of the invention is defined by the claims and their equivalents.

Claims (10)

1. A device for adsorption and removal of flue gas containing nitrogen oxides, characterized in that it comprises: Adsorption tower (109), ozone generator (108), dehydration separator (107), precooler (105) and ozone removal device (111); Described adsorption tower (109) inlet end is connected by pipeline Described dehydration separator (107) and described ozone generator (108), described adsorption tower (109) gas outlet end is connected with ozone removal device (108) by pipeline, and described dehydration separator (107) intake air end is connected to the precooler (105) through a pipeline, the inlet end of the precooler (105) is connected to the boiler (101) through a pipeline, and the outlet end of the dehydration separator (107) is provided with a nitric oxide concentration sensor (1071), an ozone concentration sensor (1081) is provided at the gas outlet of the ozone generator (108). 2. A nitrogen oxide-containing flue gas adsorption and removal device according to claim 1, characterized in that: Several activated carbon mesh plates (1115) are arranged at intervals in the ozone removal device (111). The two ends are connected with the bottom wall of the chute offered on the limiting plate (1117) by back-moving springs (1119), and the limiting plate (1117) is installed on the inner wall of the ozone removal device (111), so Through holes (1116) are evenly distributed on the activated carbon mesh plates (1115), connecting plates (1120) are connected between the activated carbon mesh plates (1115), and the ozone removal device (111) is provided with a cam mechanism (1118 ), the cam mechanism (1118) abuts against the connecting plate (1120). 3. A device for adsorption and removal of flue gas containing nitrogen oxides according to claim 1, characterized in that: an air pump (110) is provided at the air inlet of the ozone removal device (111), and the ozone removal device The gas outlet of the removal device (111) is successively provided with an ozone detection device (112) and a solenoid valve. 4. A nitrogen oxide-containing flue gas adsorption and removal device according to claim 1, characterized in that: the outlet end of the boiler (101) is also sequentially connected to a booster fan (102), an air preheater (103 ) and a dust collector (104), the gas outlet of the dust collector (104) is connected to the precooler (105). 5 . The device for adsorption and removal of flue gas containing nitrogen oxides according to claim 4 , characterized in that: a temperature sensor ( 106 ) is provided at the gas outlet end of the precooler ( 105 ). 6. A device for adsorption and removal of flue gas containing nitrogen oxides according to claim 1, characterized in that: the outlet of the adsorbent at the bottom of the adsorption tower (109) is connected with an adsorbent regeneration tower (113), the The inlet end of the adsorbent regeneration tower (113) is connected with a heat source input device (114) through a pipeline. 7. A nitrogen oxide-containing flue gas adsorption and removal device according to claim 6, characterized in that: the adsorbent regeneration tower (113) is connected to the lye adsorption device (115) through a pipeline, and the lye The adsorption device (115) is used for absorbing and treating the nitrogen oxides desorbed by the adsorbent through heating. 8. A method for adsorption and removal of flue gas containing nitrogen oxides, characterized in that the method comprises: The flue gas produced by the boiler is introduced into the pre-cooler, and the pre-cooler reduces the temperature of the flue gas to below 80°C; Introducing the cooled flue gas into the water separator to dry the cooled flue gas; The dried flue gas is introduced to the ozone dosing point, and the ozone dosing point is introduced into the adsorption tower to mix with the flue gas; The flue gas adsorbed by the adsorption tower is introduced into the ozone removal device, and the ozone removal device reduces and decomposes excess ozone in the flue gas. 9. A method for adsorption and removal of flue gas containing nitrogen oxides according to claim 8, characterized in that the method further comprises: the adsorption tower adopts a fixed bed adsorption tower or a moving bed adsorption tower, wherein , when the adsorption material saturated in the adsorption tower is used for regeneration, if a fixed bed adsorption tower is used, then heating and regeneration is carried out in the fixed bed adsorption tower; if a moving bed adsorption tower is used, the moving bed The adsorption material in the type adsorption tower is moved to the regeneration equipment for heating and regeneration. 10. A method for adsorption and removal of flue gas containing nitrogen oxides according to claim 8, characterized in that the dried flue gas is introduced into the ozone dosing point, and the ozone dosing point is introduced into ozone and Said flue gas is mixed and passed into the adsorption tower and also includes: The nitric oxide concentration and the ozone concentration in the flue gas passed into the adsorption tower are detected, and the volume ratio of the ozone and the nitric oxide in the flue gas is greater than 1:1 through the control of the solenoid valve.

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