CN212236611U

CN212236611U - Switching type fixed bed flue gas treatment system

Info

Publication number: CN212236611U
Application number: CN202021207439.9U
Authority: CN
Inventors: 程伟良
Original assignee: Individual
Current assignee: Individual
Priority date: 2020-06-28
Filing date: 2020-06-28
Publication date: 2020-12-29
Anticipated expiration: 2030-06-28

Abstract

The utility model belongs to the flue gas treatment field, concretely relates to switching formula fixed bed flue gas processing system. The device comprises a flue gas purification channel, wherein the flue gas purification channel consists of a flue gas inlet pipeline, a fixed bed A, an ammonia mixing device, a fixed bed D and a flue gas outlet pipeline which are sequentially arranged, a switching valve is arranged between every two adjacent devices in the devices, the fixed bed A is also provided with the fixed bed B and the fixed bed C in parallel, the ammonia mixing device is also provided with a sulfur separation device in parallel, the fixed bed D is also provided with the fixed bed E in parallel, and each fixed bed is filled with active coke; the flue gas purification channel is provided with a regeneration loop and a cooling loop in parallel. The utility model discloses avoided the transportation when the active burnt regeneration of saturated absorption to handle the puzzlement in the conventional method, reduced consumption and the fire accident to active burnt in transportation process, increased the utilization ratio of active burnt to reduce the area that traditional SOx/NOx control system arranged.

Description

Switching type fixed bed flue gas treatment system

Technical Field

The utility model belongs to the flue gas treatment field, concretely relates to switching formula fixed bed flue gas processing system.

Background

In recent years, the atmospheric pollution is serious and the environment is damaged in China, and SO in boiler flue gas of coal-fired power plants and enterprises in related industries₂NOx is the main emission source, and the urgent need is to adopt the advanced technology to control the atmospheric emission. At present, the main desulfurization mode is limestone-gypsum wet desulfurization, which is technically mature and should be usedThe method has the advantages that the method is wide in application range, low in exhaust smoke temperature and easy to corrode equipment, gypsum rain can be generated at the outlet of a chimney, the emission of smoke dust PM2.5 is increased easily, the generated desulfurization waste water is difficult to treat, and the waste gypsum accumulation can cause secondary pollution to the environment; the denitration adopts the SCR technology of adding ammonia by catalyzing flue gas, the required temperature is high, and simultaneously, the ash content of the flue gas is high, so that the blockage, sintering and the like of the catalyst are easily caused. The desulfurization and denitrification of the active coke can realize SO₂The NOx resource utilization and the advanced technology without secondary pollution do not need water resource consumption, the desulfurization and denitrification efficiency is more than 95 percent, and SO generated by adsorption₂Can be used for producing products such as sulfuric acid, sulfur and the like, relieves the problem of shortage of sulfur resources in China, and has low possibility of generating white fog because the smoke discharge temperature of active coke desulfurization is about 100 ℃.

At present, active coke flue gas purification devices are composed of an active coke adsorption tower, a regeneration tower and an active coke conveying system, active coke after flue gas is treated by the adsorption tower is conveyed to the regeneration tower by the conveying system for regeneration, the adsorption performance of the active coke is recovered after regeneration, and the active coke is conveyed back to the adsorption tower to adsorb the flue gas. In the transportation process of active coke, the collision between active coke and each device casing and active coke granule can cause the damage of active coke, and flow density is big, and the unable smooth horizontal passing through of desulfurization flue gas needs in time to clear up out broken active coke, and then has increased the loss of active coke, influences its adsorption effect. Meanwhile, the used active coke has high shaping and processing difficulty, high energy consumption and high density, and the internal adsorption thickness of the active coke is shallow, so that the adsorption capacity of all the active coke is seriously insufficient; the purification device occupies a large area, has a long material conveying process, can generate air leakage, dust raising and possible fire accidents along the way, and is not beneficial to realizing stable conveying.

Disclosure of Invention

Active burnt loss in order to solve current flue gas purification device is big, the high problem of material transport cost, the utility model provides a switching formula fixed bed flue gas processing system.

In order to achieve the above purpose, the utility model adopts the following technical scheme:

a switching type fixed bed flue gas treatment system comprises a flue gas purification channel, wherein the flue gas purification channel consists of a flue gas inlet pipeline, an A fixed bed, an ammonia mixing device, a D fixed bed and a flue gas outlet pipeline which are sequentially arranged, a switching valve is arranged between every two adjacent devices in the devices, the A fixed bed is also provided with a B fixed bed and a C fixed bed in parallel, the ammonia mixing device is also provided with a sulfur separation device in parallel, the D fixed bed is also provided with an E fixed bed in parallel, and each fixed bed is filled with active coke; the flue gas purification channel is provided with a regeneration loop and a cooling loop in parallel.

Furthermore, the regeneration loop is a closed loop and sequentially comprises a gas inlet three-way switching valve, a fixed bed B, a gas exhaust three-way switching valve, a sulfur separation device, a gas inlet two-way switching valve, an E fixed bed and an electric heater which are connected by pipelines.

Further, the cooling loop is a closed loop and sequentially comprises an air inlet three-way switching valve, a C fixed bed, an air outlet three-way switching valve and a refrigerator which are connected through pipelines.

Further, a heat exchanger is arranged on the regeneration loop, and the heat exchanger and the cooling loop share the same.

Furthermore, a regeneration air pump is arranged on the regeneration loop, and a cooling air pump is arranged on the cooling loop.

Further, the active coke in the fixed bed is in a honeycomb type with layered annular belt-shaped areas.

Further, the bulk density of the active coke is 450-500 kg/m³。

Further, the inlet line and the outlet line of each switching valve are independently and switchably connected.

Furthermore, high-temperature nitrogen gas at 300-450 ℃ is introduced into the regeneration loop, and low-temperature nitrogen gas at 100-120 ℃ is introduced into the cooling loop.

Compared with the prior art, the utility model discloses following beneficial effect has:

the utility model discloses a plurality of diverter valves set up parallelly connected flue gas passageway, regeneration circuit and cooling circuit, can carry out pollutant adsorption, active coke regeneration and active coke refrigerated processing to the fixed bed in the system simultaneously, saved the transportation link of the active coke that will saturate adsorption, reduced the consumption to active coke in the transportation process, increased the utilization ratio of active coke, can avoid the high energy consumption and the adsorption capacity waste phenomenon of active coke design superhigh pressure processing; when the activated coke fixed bed in the flue gas channel is subjected to saturated adsorption, the flue gas can be immediately switched to the regenerated and cooled fixed bed through the switching valve for adsorption, so that the equipment shutdown phenomenon caused by activated coke replacement is avoided; the utility model discloses switching formula fixed bed flue gas processing system can realize that flue gas desulfurization denitration and active burnt regenerative cooling's compact arrange, reduces the area that traditional SOx/NOx control system arranged.

Drawings

FIG. 1 is a schematic diagram of a switched fixed bed flue gas treatment system;

FIG. 2 is a schematic view of the structure of a fixed bed.

In the drawings, the reference numbers: the device comprises a gas inlet three-way switching valve 1, a gas outlet three-way switching valve 2, a gas inlet two-way switching valve 3, a gas outlet two-way switching valve 4, a fixed bed A5, a fixed bed B6, a fixed bed C7, a fixed bed D8, a fixed bed E9, an ammonia mixing device 10, a sulfur separating device 11, a heat exchanger 12, an electric heater 13, a refrigerator 14, a regeneration air pump 15, a cooling air pump 16, a heat insulating layer 50, active coke 51, a porous partition plate 52, a gas inlet mixing chamber 53, a gas outlet mixing chamber 54, a gas outlet 55 and a gas inlet 56.

Detailed Description

The invention will be further explained and explained with reference to the drawings.

A switching type fixed bed flue gas treatment system comprises a flue gas purification channel as shown in figure 1, wherein the flue gas purification channel consists of a flue gas inlet pipeline, an A fixed bed 5, an ammonia mixing device 10, a D fixed bed 8 and a flue gas outlet pipeline which are sequentially arranged, a switching valve is arranged between every two adjacent devices in the devices, namely, a gas inlet three-way switching valve 1 is arranged between the flue gas inlet pipeline and the A fixed bed 5, a gas outlet three-way switching valve 2 is arranged between the A fixed bed 5 and the ammonia mixing device 10, a gas inlet two-way switching valve 3 is arranged between the ammonia mixing device 10 and the D fixed bed 8, a gas outlet two-way switching valve 4 is arranged between the D fixed bed 8 and the flue gas outlet pipeline, a desulfurization stage is arranged between the gas inlet three-way switching valve 1 and the gas outlet three-way switching valve 2, and, the transition stage is arranged between the desulfurization stage and the denitration stage;

a B fixed bed 6 and a C fixed bed 7 are further arranged at the A fixed bed 5 in parallel, a sulfur separation device 11 is further arranged at the ammonia mixing device 10 in parallel, an E fixed bed 9 is further arranged at the D fixed bed 8 in parallel, and each fixed bed is filled with active coke; the flue gas purification channel is provided with a regeneration loop and a cooling loop in parallel.

As an embodiment, the regeneration loop is a closed loop, and comprises a gas inlet three-way switching valve 1, a B fixed bed 6, an exhaust three-way switching valve 2, a sulfur separation device 11, a gas inlet two-way switching valve 3, an E fixed bed 9 and an electric heater 13 which are connected by pipelines in sequence.

As an implementation mode, the cooling loop is a closed loop and sequentially comprises a gas inlet three-way switching valve 1, a C fixed bed 7, an exhaust three-way switching valve 2 and a refrigerator 14 which are connected by pipelines, and the fixed bed regenerated in the desulfurization stage needs to be cooled so as to be circulated to enter adsorption desulfurization; and the regenerated fixed bed in the denitration stage does not need to be cooled and directly circulates to enter the adsorption denitration, so that the cooling loop only comprises the fixed bed and the switching valve in the desulfuration stage.

As an implementation mode, the regeneration loop is further provided with a heat exchanger 12, the heat exchanger 12 and the cooling loop share for heat exchange, the nitrogen gas with the temperature lowered after regeneration absorbs heat in the heat exchanger 12, and the nitrogen gas with the temperature raised after cooling releases heat in the heat exchanger 12, so that the energy is fully recycled, and the waste is reduced.

As an embodiment, a regeneration air pump 15 is disposed on the regeneration loop, and a cooling air pump 16 is disposed on the cooling loop to provide power for the circulation of the regeneration air and the cooling air.

As an implementation mode, the active coke in the fixed bed is in a honeycomb type with layered annular belt-shaped areas, the thickness is 1mm, the contact area during reaction is large, the flowing is not needed, the active coke cannot be broken, and the adsorption and the regeneration of the active coke are greatly facilitated.

In the utility model, all the fixed beds have the same structure, for example, the fixed bed A5 is a tank body, as shown in fig. 2, the fixed bed A5 is a tank body, a plurality of horizontal porous partition plates 52 are arranged in the tank body, active coke 51 is shaped and stacked on each layer of the porous partition plates 52, an air inlet mixing chamber 53 and an air inlet are arranged below the porous partition plate 52 at the lowest layer, and an exhaust mixing chamber 54 and an exhaust port are arranged on the active coke 51 at the uppermost layer; the periphery of the tank body is provided with a heat-insulating lining to form a heat-insulating layer 50, so that air leakage and heat dissipation of the A fixed bed 5 are avoided. During the operation of the device, all gases enter from a lower gas inlet 56 of the A fixed bed 5, sequentially pass through the gas inlet mixing chamber 53, pass through the multistage active coke 51 for adsorption desulfurization (or regeneration after desulfurization, or cooling, or denitration, or regeneration after denitration), and then flow out from an upper gas outlet 55 through the exhaust mixing chamber 54.

Further, the bulk density of the active coke 51 is 450-500 kg/m³. The density is smaller than that of the conventional short rod-shaped packing mode, so that the space volume among the active coke 51 particles can be increased, and the adsorption regeneration reaction of the active coke 51 can be fully performed.

As an implementation mode, the inlet pipeline and the outlet pipeline of each switching valve are independently, one-to-one and switchably connected, the channels of each switching valve are insulated, and the switching valve is cylindrical and comprises an air inlet connecting part, a switching part and a motor driving part and is switched in a unidirectional intermittent mode. Taking the air inlet three-way switching valve 1 as an example, the inlet gas is flue gas, regeneration gas and cooling gas respectively, when the three gases respectively enter the air inlet three-way switching valve 1, the inlet pipelines of the switching part respectively correspond to the outlet pipelines one by one and are conveyed to different fixed beds, namely, one gas can only simultaneously enter and exit the same fixed bed, namely, when the A fixed bed 5 enters and exits flue gas for adsorption desulfurization, the B fixed bed 6 enters and exits the regeneration gas for active coke regeneration, the C fixed bed 7 enters and exits the cooling gas for cooling, and the principles and processes of the exhaust three-way switching valve 2, the air inlet two-way switching valve 3 and the exhaust two-way switching valve 4 are the same as those of.

As an implementation mode, high-temperature nitrogen is introduced into the regeneration loop and flows as regeneration gas, the temperature of the high-temperature nitrogen is 300-450 ℃, the regeneration gas is used for heating and regenerating the active coke saturated with pollutants in the adsorption flue gas, SO that SO adsorbed by the active coke₂When the SO is desorbed, the adsorption desulfurization capability of the active coke is recovered, and the desorbed SO₂Is removed by a sulfur separation device 11; and low-temperature nitrogen (100-120 ℃) is introduced into the cooling loop and flows as cooling gas, and the cooling gas is used for cooling the activated coke with higher temperature after heating and regeneration so as to meet the requirement of the desulfurization temperature of the activated coke.

When the fixed bed 5A is a desulfurization fixed bed, the fixed beds B6 and E9 are regeneration fixed beds, the fixed bed C7 is a cooling fixed bed, and the fixed bed D8 is a denitration fixed bed, the circulation working process of the flue gas channel, the regeneration loop and the cooling loop is as follows:

a flue gas channel: flue gas inlet pipeline that the flue gas passes through gets into air inlet three ways diverter valve 1, then gets into A fixed bed 5, and the flue gas is desulfurized to the active burnt, gets into and mixes ammonia device 10 through exhaust three ways diverter valve 2 again, and flue gas after the desulfurization mixes with the ammonia, gets into D fixed bed 8 through air inlet two ways diverter valve 3 and carries out the active burnt denitration of adsorbing, and the flue gas after at last the desulfurization denitration is discharged through the flue gas outlet pipeline behind exhaust two ways diverter valve 4.

A regeneration loop: introducing high-temperature nitrogen (300-450 ℃) into the system, introducing the nitrogen into the air inlet three-way switching valve 1, then introducing the nitrogen into the B fixed bed 6, and desorbing SO adsorbed by active coke in the nitrogen₂Then enters a sulfur separation device 11 through an exhaust three-way switching valve 2 to carry out SO₂The regenerated gas is pressurized by the exhaust two-way switching valve 4 and the regeneration air pump 15, enters the heat exchanger 12 for absorbing heat, enters the electric heater 13 for auxiliary heating, and then enters the intake three-way switching valve 1 again as the regenerated gas.

A cooling circuit: the low-temperature nitrogen introduced into the system enters the air inlet three-way switching valve 1, then enters the C fixed bed 7, cools the high-temperature active coke after thermal regeneration, then directly enters the heat exchanger 12 through the air outlet three-way switching valve 2 to release heat, then is pressurized by the cooling air pump 16, is refrigerated by the refrigerator 14 in an auxiliary mode, and then enters the air inlet three-way switching valve 1 again as cooling air.

The flue gas channel, the regeneration loop and the cooling loop are carried out simultaneously, the types of the introduced gases are different, and the reactions of the active coke in the fixed beds are different. When the introduced gas is flue gas, the A fixed bed 5 and the D fixed bed 8 respectively carry out desulfurization and denitration adsorption reactions; when the introduced gas is the regeneration gas, the regeneration reaction of the active coke is respectively carried out in the B fixed bed 6 and the E fixed bed 9; when the introduced gas is cooling gas, the C fixed bed 7 is subjected to a cooling process of the active coke. When the active coke adsorption in the flue gas channel is close to saturation and needs regeneration, the corresponding channel of the switching valve is changed, the regenerated and cooled fixed bed is used as a new fixed bed for flue gas desulfurization and denitration, and the active coke fixed bed saturated and absorbing pollutants is regenerated and cooled for recycling.

In addition, the utility model can also combine the adsorption rate of active coke desulfurization to control the amounts of the regenerated gas and the cooling gas of the regeneration loop and the cooling loop, thereby ensuring the dynamic balance among adsorption, regeneration and cooling; the nitrogen amount of a regeneration loop is controlled by combining the adsorption rate of the activated coke denitration, so that the dynamic balance between the adsorption and regeneration of the denitration is ensured; and the continuous and stable operation of the whole desulfurization and denitrification system is ensured.

Although the embodiments of the present invention have been described and illustrated, it is not intended to be limited to the specific embodiments shown, but is to be accorded the widest scope consistent with the principles and novel features herein disclosed.

Claims

1. The utility model provides a switching formula fixed bed flue gas processing system, includes the flue gas purification passageway, the flue gas purification passageway comprises flue gas inlet pipeline, A fixed bed (5), ammonia mixing device (10), D fixed bed (8) and the exhanst gas outlet pipeline that sets gradually, its characterized in that: a switching valve is arranged between every two adjacent devices in the devices, a B fixed bed (6) and a C fixed bed (7) are further arranged at the A fixed bed (5) in parallel, a sulfur separation device (11) is further arranged at the ammonia mixing device (10) in parallel, an E fixed bed (9) is further arranged at the D fixed bed (8) in parallel, and active coke is filled in each fixed bed; the flue gas purification channel is provided with a regeneration loop and a cooling loop in parallel.

2. The switched fixed bed flue gas treatment system according to claim 1, wherein the regeneration loop is a closed loop comprising a gas inlet three-way switching valve (1), a B fixed bed (6), a gas outlet three-way switching valve (2), a sulfur separation device (11), a gas inlet two-way switching valve (3), an E fixed bed (9) and an electric heater (13) connected by pipelines in sequence.

3. A switched fixed bed flue gas treatment system according to claim 1, wherein the cooling loop is a closed loop comprising in sequence an inlet three-way switching valve (1), a fixed bed (7), an outlet three-way switching valve (2) and a refrigerator (14) connected by a pipeline.

4. A switched fixed bed flue gas treatment system according to claim 1, wherein a heat exchanger (12) is further provided on the regeneration circuit, the heat exchanger (12) being common to the cooling circuit.

5. The switched fixed bed flue gas treatment system according to claim 1, wherein a regeneration air pump (15) is disposed on the regeneration loop, and a cooling air pump (16) is disposed on the cooling loop.

6. The switched fixed bed flue gas treatment system of claim 1, wherein the activated coke in the fixed bed is in the form of a honeycomb having annular band zones layered.

7. The switched fixed bed flue gas treatment system of claim 6, wherein the bulk density of the activated coke is 450-500 kg/m³。

8. The switched fixed bed flue gas treatment system of claim 1, wherein the inlet line and the outlet line of each switching valve are independently and switchably connected.

9. The switching type fixed bed flue gas treatment system as claimed in claim 1, wherein the regeneration loop is filled with high temperature nitrogen at 300-450 ℃, and the cooling loop is filled with low temperature nitrogen at 100-120 ℃.