Fluidized bed furnace flue gas denitrification treatment device

Abstract

The utility model relates to the technical field of flue gas denitrification, and is a fluidized bed flue gas denitrification treatment device, which includes a fluidized bed furnace, a urea hydrolyzer, a denitrification reactor, a drying kiln, and a dust collector. The denitrification reactor includes a flue and a catalytic bed. A flue gas pipeline is connected between the fluidized bed furnace and the flue, a hydrolyzed ammonia pipeline is connected between the urea hydrolyzer and the flue, a denitrification pipeline is connected between the catalytic bed and the drying kiln, a dry gas pipeline is connected between the drying kiln and the dust collector, and a purified gas pipeline is connected to the dust collector. The utility model has a reasonable and compact structure and is easy to use. It can reduce the emission concentration of nitrogen oxides in the flue gas discharged by the fluidized bed furnace, improve the on-site working environment, and fully assist the sustainable and high-quality development of enterprises. It has the characteristics of labor saving, simplicity, and high efficiency.

Description

Technical Field

[0001] The utility model relates to the technical field of flue gas denitration, and is a device for denitration of flue gas from a boiling furnace. Background Art

[0002] Nitrogen oxides (NO) X , including a variety of compounds, such as nitrous oxide (N2O), nitric oxide (N0), nitrogen dioxide (NO2), dinitrogen trioxide (N203), dinitrogen tetroxide (N204) and dinitrogen pentoxide (N205). Except for nitrogen dioxide (NO2), other nitrogen oxides are extremely unstable. When exposed to light, moisture or heat, they will generate nitrogen dioxide and nitric oxide, and nitric oxide will generate nitrogen dioxide. Therefore, the mixture of several nitrogen oxide gases that are exposed in the occupational environment is often called gunpowder (gas), which is mainly nitric oxide and nitrogen dioxide, with nitrogen dioxide as the main component.

[0003] Nitrogen oxides (NO x ) have different degrees of toxicity, NO x It can enter the deep lungs through breathing and cause bronchitis or emphysema. x It can also react with other pollutants in the atmosphere to form photochemical smog pollution. N2O is oxidized into nitric acid in the atmosphere, which is one of the causes of acid rain. N2O can also reduce ozone in the stratosphere, thereby increasing the amount of ultraviolet radiation reaching the earth.

[0004] NO x Pollution is related to the use of mineral fuels as energy. The fuel for the fluidized bed furnace, an important equipment of a certain enterprise, is the purified ash from the calcium carbide furnace, which is transported by pneumatic force. The main harmful substances in the exhaust gas of the fluidized bed furnace include smoke, SO2, NO x , the smoke emission concentration is 20mg / Nm 3 , the emission concentration of SO2 is 2mg / Nm 3 , NO x The emission concentration is 200mg / Nm 3 Up to 300mg / Nm 3 The temperature of the flue gas emitted by the fluidized bed furnace is 220℃ to 300℃, and the flue gas emitted by the fluidized bed furnace does not meet the environmental standards for nitrogen oxide emissions (converted into NO2) stipulated in China's "Air Environment Quality Standards". Therefore, it is difficult for enterprises to overcome the technical difficulties of making the flue gas emission indicators of the fluidized bed furnace meet the national statutory standards, protect the atmospheric ecological environment, and ensure the normal production and operation of the equipment. Summary of the invention

[0005] The utility model provides a denitration treatment device for flue gas from a fluidized bed furnace, which overcomes the deficiencies of the prior art and can effectively solve the problem of excessive nitrogen oxides in flue gas discharged from fluidized bed furnaces of existing chemical enterprises.

[0006] The technical scheme of the utility model is achieved through the following measures: a denitration treatment device for flue gas from a fluidized bed furnace, comprising a fluidized bed furnace, a urea hydrolyzer, a denitration reactor, a drying kiln, and a dust collector, wherein the denitration reactor comprises a flue and a catalytic bed, a flue gas pipeline is fixedly connected between an upper air outlet of the fluidized bed furnace and an air inlet at the bottom of the flue, a hydrolyzed ammonia pipeline is fixedly connected between an air outlet at the top of the urea hydrolyzer and an air inlet in the middle of the flue, a denitration pipeline is fixedly connected between an air outlet at the bottom of the catalytic bed and an air inlet at the bottom of the drying kiln, a dry gas pipeline is fixedly connected between the middle air outlet of the drying kiln and an upper air inlet of the dust collector, and a purified gas pipeline is fixedly connected between the middle air outlet of the dust collector.

[0007] The following are further optimizations and / or improvements to the above utility model technical solution:

[0008] An ammonia injection grid is arranged in the middle of the flue.

[0009] A catalyst layer is arranged in the catalyst bed.

[0010] A remote liquid level gauge is fixedly arranged on the urea hydrolyzer.

[0011] The first fan and the static mixer are fixedly installed in sequence on the hydrolyzed ammonia pipeline along the medium flow direction.

[0012] The flue gas pipeline is fixedly connected with a first detection pipeline, and the denitration pipeline is fixedly connected with a second detection pipeline.

[0013] A second fan is fixedly installed on the denitration pipeline between the second detection pipeline and the lower air inlet of the drying kiln.

[0014] The top liquid inlet of the urea hydrolyzer is fixedly connected with a urea solution pipeline, the upper liquid inlet of the urea hydrolyzer is fixedly connected with a steam pipeline, and the lower liquid outlet of the urea hydrolyzer is fixedly connected with a drain pipeline.

[0015] A first solenoid valve is fixedly installed on the urea solution pipeline, a second solenoid valve is fixedly installed on the steam pipeline, and a third solenoid valve is fixedly installed on the drain pipeline.

[0016] The above also includes a controller, and the remote liquid level meter, the first solenoid valve, the second solenoid valve, and the third solenoid valve are all electrically connected to the controller.

[0017] The utility model has a reasonable and compact structure and is easy to use. It can effectively reduce the emission concentration of nitrogen oxides in the flue gas emitted by the boiling furnace, improve the on-site working environment, and comprehensively assist the sustainable and high-quality development of the enterprise. It is safe, labor-saving, simple and efficient. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Attached Figure 1 This is a schematic diagram of the process flow of the utility model.

[0019] Attached Figure 1 The codes are as follows: 1 is a boiling furnace, 2 is a urea hydrolyzer, 3 is a denitrification reactor, 4 is a drying kiln, 5 is a dust collector, 6 is a flue, 7 is a catalyst bed, 8 is a flue gas pipeline, 9 is a hydrolyzed ammonia pipeline, 10 is a denitrification pipeline, 11 is a dry gas pipeline, 12 is a purified gas pipeline, 13 is an ammonia injection grid, 14 is a catalyst layer, 15 is a remote liquid level gauge, 16 is the first fan, 17 is a static mixer, 18 is the first detection pipeline, 19 is the second detection pipeline, 20 is the second fan, 21 is a urea solution pipeline, 22 is a steam pipeline, 23 is a drain pipeline, 24 is a first solenoid valve, 25 is a second solenoid valve, and 26 is a third solenoid valve. DETAILED DESCRIPTION

[0020] The present invention is not limited by the following embodiments, and specific implementation methods can be determined according to the technical solution of the present invention and actual conditions.

[0021] In the present invention, unless otherwise specified, the equipment and devices used are all the equipment and devices known and used in the art.

[0022] In the present invention, for the convenience of description, the relative position relationship of each component is described according to the attached manual. Figure 1 The layout is described in detail, such as the positional relationship of front, back, top, bottom, left, right, etc., which is based on the attached manual. Figure 1 It is determined by the layout direction.

[0023] The present invention is further described below in conjunction with the embodiments and drawings:

[0024] Embodiment 1: As attached Figure 1As shown, the fluidized bed flue gas denitration treatment device comprises a fluidized bed 1, a urea hydrolyzer 2, a denitration reactor 3, a drying kiln 4, and a dust collector 5. The denitration reactor 3 comprises a flue 6 and a catalytic bed 7. A flue gas pipeline 8 is fixedly connected between the upper air outlet of the fluidized bed 1 and the bottom air inlet of the flue 6. A hydrolyzed ammonia pipeline 9 is fixedly connected between the top air outlet of the urea hydrolyzer 2 and the middle air inlet of the flue 6. A denitration pipeline 10 is fixedly connected between the bottom air outlet of the catalytic bed 7 and the lower air inlet of the drying kiln 4. A dry gas pipeline 11 is fixedly connected between the middle air outlet of the drying kiln 4 and the upper air inlet of the dust collector 5. A purified gas pipeline 12 is fixedly connected to the middle air outlet of the dust collector 5.

[0025] The main harmful substances in the exhaust gas of the boiling furnace 1 include smoke, SO2, NO x , the smoke emission concentration is 20mg / Nm 3 , the emission concentration of SO2 is 2mg / Nm 3 , NO x The emission concentration is 200mg / Nm 3 Up to 300mg / Nm 3 The temperature of the flue gas discharged from the fluidized bed furnace is 220°C to 300°C. According to the exhaust gas working conditions of the fluidized bed furnace 1, the SO2 concentration is low and the smoke is small, which meets the conditions required by the SCR denitrification process. Therefore, the denitrification reactor 2 is used to remove NO in the exhaust gas of the fluidized bed furnace 1. x , change NO x Emission concentration reduced to ≤50mg / Nm 3 . Effectively solve the NO in the flue gas discharged from the boiling furnace 1 x The problem of substandard content is further helped to improve the productivity of enterprises while their emission indicators also meet the national environmental protection emission standards.

[0026] As required, the catalytic bed 7 can make the flue gas flow smoothly and distribute the airflow evenly, thereby promoting the flue gas denitration reaction.

[0027] The above-mentioned fluidized bed furnace flue gas denitrification treatment device can be further optimized and / or improved according to actual needs:

[0028] Embodiment 2: It is different from Embodiment 1 in that: Figure 1 As shown, an ammonia injection grid 13 is arranged in the middle of the flue 6.

[0029] Embodiment 3: It differs from Embodiment 1 to Embodiment 2 in that: Figure 1 As shown, a catalyst layer 14 is arranged in the catalyst bed 7 .

[0030] As required, one or more catalyst layers 14 may be provided in the catalyst bed 7 as required.

[0031] Embodiment 4: It differs from Embodiments 1 to 3 in that: Figure 1 As shown, a remote liquid level meter 15 is fixedly arranged on the urea hydrolyzer 2 .

[0032] Embodiment 5: It differs from Embodiments 1 to 4 in that: Figure 1 As shown, a first fan 16 and a static mixer 17 are fixedly installed in sequence on the hydrolyzed ammonia pipeline 9 along the flow direction of the medium.

[0033] According to the needs, the ammonia in the hydrolyzed ammonia pipeline 9 contains a large amount of water vapor, and the static mixer 17 can make the gaseous medium and the liquid medium in the hydrolyzed ammonia pipeline 9 mixed, refined and evenly distributed.

[0034] Embodiment 6: It differs from Embodiments 1 to 5 in that: Figure 1 As shown, the flue gas pipeline 8 is fixedly connected to a first detection pipeline 18 , and the denitration pipeline 10 is fixedly connected to a second detection pipeline 19 .

[0035] As required, NO in the flue gas before entering the denitrification reactor 3 can be collected through the first detection pipeline 18. x If the emission concentration is high, the steam input to the urea hydrolyzer 2 can be increased to accelerate the hydrolysis of urea into ammonia and increase the steam input to the denitration reactor 3.

[0036] Embodiment 7: It differs from Embodiments 1 to 6 in that: Figure 1 As shown, a second fan 20 is fixedly installed on the denitration pipeline 10 between the second detection pipeline 19 and the lower air inlet of the drying kiln 4.

[0037] As required, the frequency of the motor of the second fan 20 can be increased to increase the input amount of ammonia gas entering the denitration reactor 3.

[0038] Embodiment 8: It differs from Embodiments 1 to 7 in that: Figure 1 As shown, the top liquid inlet of the urea hydrolyzer 2 is fixedly connected to a urea solution pipeline 21 , the upper liquid inlet of the urea hydrolyzer 2 is fixedly connected to a steam pipeline 22 , and the lower liquid outlet of the urea hydrolyzer 2 is fixedly connected to a drain pipeline 23 .

[0039] Embodiment 9: It differs from Embodiments 1 to 8 in that: Figure 1 As shown, a first solenoid valve 24 is fixedly installed on the urea solution pipeline 21 , a second solenoid valve 25 is fixedly installed on the steam pipeline 22 , and a third solenoid valve 26 is fixedly installed on the drain pipeline 23 .

[0040] Embodiment 10: It differs from Embodiments 1 to 9 in that: Figure 1As shown, the device also includes a controller, and the remote liquid level meter 15, the first solenoid valve 24, the second solenoid valve 25, and the third solenoid valve 26 are all electrically connected to the controller.

[0041] According to the needs, the pipelines and equipment of the boiling furnace flue gas denitration treatment device can also be equipped with conventional valves, thermometers and pressure gauges known in the art according to production needs. The controller in the utility model is a DCS controller, and the model of the DCS controller can be the CS3000 controller produced by Yokogawa Corporation of Japan.

[0042] The above technical features constitute the embodiments of the present utility model, which have strong adaptability and implementation effect. Non-essential technical features can be added or reduced according to actual needs to meet the requirements of different situations.

[0043] The use process of the embodiment of the utility model is as follows: first, the exhaust flue gas in the boiling furnace 1 enters the flue 6 through the flue gas pipeline 8; then, the urea hydrolyzer 2 hydrolyzes the urea solution to generate ammonia, and the ammonia enters the static mixer 17 through the hydrolysis ammonia pipeline 9 for gas-liquid homogeneous mixing. After the homogenized ammonia enters the flue 6, the ammonia is sprayed through the ammonia spray grid 13; then, the ammonia and flue gas in the flue 6 enter the catalytic bed 7, and under the action of the catalyst, the ammonia reacts with the nitrogen oxides (NO x ) undergoes a reduction reaction to generate nitrogen and water; finally, the flue gas after denitration in the denitration reactor 3 enters the drying kiln 4 through the denitration pipeline 10 for drying treatment, and the dried denitration flue gas enters the dust collector 5 through the dry gas pipeline 11 for dust removal. The gas that meets the emission standards is discharged into the atmosphere through the purified gas pipeline 12.

Claims

1. A denitrification treatment device for flue gas from a fluidized bed furnace, characterized in that It includes a fluidized bed furnace, a urea hydrolyzer, a denitrification reactor, a drying kiln and a dust collector. The denitrification reactor includes a flue and a catalytic bed. A flue gas pipeline is fixedly connected between the upper air outlet of the fluidized bed furnace and the bottom air inlet of the flue. A hydrolyzed ammonia pipeline is fixedly connected between the top air outlet of the urea hydrolyzer and the middle air inlet of the flue. A denitrification pipeline is fixedly connected between the bottom air outlet of the catalytic bed and the lower air inlet of the drying kiln. A dry gas pipeline is fixedly connected between the middle air outlet of the drying kiln and the upper air inlet of the dust collector. A purified gas pipeline is fixedly connected to the middle air outlet of the dust collector.

2. The denitration treatment device for flue gas from a fluidized bed furnace according to claim 1 is characterized in that An ammonia injection grid is arranged in the middle of the flue.

3. The denitration treatment device for fluidized bed furnace flue gas according to claim 1 or 2, characterized in that A catalyst layer is arranged in the catalyst bed.

4. The denitration treatment device for flue gas from a fluidized bed furnace according to claim 3 is characterized in that A remote level gauge is fixedly installed on the urea hydrolyzer.

5. The denitration treatment device for flue gas from a fluidized bed furnace according to claim 1, 2 or 4, characterized in that A first fan and a static mixer are fixedly installed in sequence on the hydrolyzed ammonia pipeline along the medium flow direction.

6. The denitration treatment device for flue gas from a fluidized bed furnace according to claim 5 is characterized in that The flue gas pipeline is fixedly connected with a first detection pipeline, and the denitration pipeline is fixedly connected with a second detection pipeline.

7. The denitration treatment device for flue gas from a fluidized bed furnace according to claim 6 is characterized in that A second fan is fixedly installed on the denitration pipeline between the second detection pipeline and the lower air inlet of the drying kiln.

8. The denitration treatment device for flue gas from a fluidized bed furnace according to claim 1, 2, 4, 6 or 7, characterized in that The top liquid inlet of the urea hydrolyzer is fixedly connected with a urea solution pipeline, the upper liquid inlet of the urea hydrolyzer is fixedly connected with a steam pipeline, and the lower liquid outlet of the urea hydrolyzer is fixedly connected with a drain pipeline.

9. The denitration treatment device for flue gas from a fluidized bed furnace according to claim 8, characterized in that A first solenoid valve is fixedly installed on the urea solution pipeline, a second solenoid valve is fixedly installed on the steam pipeline, and a third solenoid valve is fixedly installed on the drain pipeline.

10. The denitration treatment device for flue gas from a fluidized bed furnace according to claim 9, characterized in that It also includes a controller, and the remote liquid level meter, the first solenoid valve, the second solenoid valve, and the third solenoid valve are all electrically connected to the controller.

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