CN215233222U

CN215233222U - Removal system for ultralow emission of nitric oxides of household garbage incinerator

Info

Publication number: CN215233222U
Application number: CN202121725962.5U
Authority: CN
Inventors: 曾永健; 徐芙蓉
Original assignee: Zhejiang Rongzhi Energy Technology Co ltd
Current assignee: Zhejiang Rongzhi Energy Technology Co ltd
Priority date: 2021-07-27
Filing date: 2021-07-27
Publication date: 2021-12-21
Anticipated expiration: 2031-07-27

Abstract

The utility model discloses a denitration system of domestic waste incinerator nitrogen oxide minimum discharge. The utility model comprises an SNCR denitration device and an SCR denitration device, wherein the SNCR denitration device is arranged on a hearth of a garbage incinerator, the SCR denitration device is arranged between a dust removal device and an induced draft fan, a flue inlet of the SCR denitration device is connected with the dust removal device, and a flue gas heat exchanger is arranged at the junction of the SCR inlet flue and the SCR outlet flue of the SCR denitration device; the outlet of the garbage incinerator is connected with the inlet of the desulfurizing device, and the outlet of the desulfurizing device is connected with the inlet of the dust removing device. Compare conventional equipment, the utility model discloses reduced heating device, cooling device and catalyst loading, reduced the energy consumption of whole equipment, more energy-concerving and environment-protective, also further reduced manufacturing cost.

Description

Removal system for ultralow emission of nitric oxides of household garbage incinerator

Technical Field

The utility model relates to a flue gas denitration device, especially a denitration system that domestic waste burns burning furnace nitrogen oxide minimum discharge.

Background

Incineration power generation is a main mode for harmless treatment of household garbage, but a large amount of atmospheric pollutants are inevitably discharged in the incineration treatment process, and the waste gas contains a large amount of Nitrogen Oxides (NO)_X) Generally, the treatment is performed by a denitration apparatus. In the prior art, an SNCR (selective non-catalytic reduction) device and an SCR (selective catalytic reduction) denitration device are two independent devices, and the SNCR technology is that a spray gun is arranged in a hearth of a garbage incinerator and Nitrogen Oxide (NO) in smoke is sprayed by a reducing agent_X) Reducing to nitrogen and water. The SCR technology is that the outlet of the dust remover is connected with the flue inlet of the denitration device, a heating device is arranged in the flue inlet of the denitration device, and a cooling device is arranged at the tail end of the flue outlet. After the flue gas is subjected to heat exchange and utilization, a part of dust particles are settled, the temperature of the flue gas is also reduced, the flue gas is heated to the optimal reaction temperature of a catalyst in the SCR denitration device through a heating device at this moment to be smoothly denitrated, and the denitrated flue gas is cooled through a cooling device to reach a certain temperature and then is finally discharged through a chimney. The heating and cooling devices arranged in the denitration device can increase extra energy consumption, are not beneficial to energy conservation and environmental protection, and increase the operation cost.

SNCR technology can burn the Nitric Oxide (NO) of the domestic garbage incinerator_X) The concentration is reduced to 150mg/Nm³About, but not satisfying 50mg/Nm³Ultra-low emission requirements.

SUMMERY OF THE UTILITY MODEL

The utility model discloses to the defect that above-mentioned prior art exists, provide a denitration system that domestic waste burns burning furnace nitrogen oxide minimum emission to effectively reduce the energy consumption, reduce the operation cost.

Therefore, the utility model adopts the following technical proposal: a removal system for ultralow emission of nitric oxides of a household garbage incinerator comprises an SNCR (selective non-catalytic reduction) denitration device and an SCR (selective catalytic reduction) denitration device, wherein the SNCR denitration device is installed on a garbage incinerator hearth, the SCR denitration device is installed between a dust removal device and an induced draft fan, a flue inlet of the SCR denitration device is connected with the dust removal device, and a flue gas heat exchanger is arranged at the intersection of an SCR inlet flue and an SCR outlet flue of the SCR denitration device;

the outlet of the garbage incinerator is connected with the inlet of the desulfurizing device, and the outlet of the desulfurizing device is connected with the inlet of the dust removing device.

An SNCR denitration device is arranged on a hearth of the garbage incinerator, and the SCR denitration device is arranged at the outlet of the dust remover. The SCR denitration device import department be equipped with the heat exchanger, SCR denitration device import flue gas carries out the heat exchange through the heat exchanger with SCR denitration device export flue gas, heats former flue gas with the clean flue gas after the denitration, reduces the system energy consumption. The utility model discloses inside integrating SNCR denitrification facility to waste incinerator, can burn burning furnace Nitrogen Oxide (NO) with domestic waste_X) The emission concentration is reduced to 150mg/Nm³Left and right. The flue gas enters an SCR device arranged behind a dust remover after being subjected to the processes of desulfurization and dust removal, and the Nitric Oxide (NO) of the household garbage incinerator can be converted into_X) The emission concentration is reduced to 50mg/Nm³The following ultra low emissions. And heat exchange devices are arranged at the inlet and the outlet of the SCR denitration device, so that the energy consumption is saved, and the system is convenient to assemble.

Furthermore, a hearth of the garbage incinerator is provided with a first layer of spray guns and a second layer of spray guns, and the first layer of spray guns and the second layer of spray guns are used for installing reducing agents.

The first layer of spray gun is used for removing Nitrogen Oxides (NO) in the incinerator under the high-load working condition_X) The second layer of spray gun is used for removing Nitrogen Oxides (NO) in the incinerator under the low-load working condition_X). The spray gun sprays the reducing agent ammonia water into the hearth to be atomized into particles with certain size, and the Nitrogen Oxide (NO) in the flue gas is uniformly sprayed into the hearth_X) Reducing to nitrogen and water. The arrangement positions of the first layer of spray guns and the second layer of spray guns are determined according to the temperature parameters of the flue gas of the hearth.

Furthermore, the SCR denitration device is connected with the dust removal device through a connecting flue.

Further, the SCR denitration device comprises an SCR inlet flue and an SCR reactor, wherein the upper parts of the SCR inlet flue and the SCR reactor are communicated; and a steam heater and an ammonia injector are arranged in the SCR inlet flue.

Furthermore, the SCR reactor is internally provided with three catalyst installation layers which are respectively used for installing a reserved layer catalyst, a first layer catalyst and a second layer catalyst.

Furthermore, the SCR outlet flue is connected with a chimney through an induced draft fan.

The original flue gas is heated primarily and then is heated again to about 200 ℃ through a steam heater, so that the flue gas is in the optimal activity range of the denitration catalyst, the denitrated clean flue gas enters a heat exchanger, and the waste heat of the clean flue gas is used for heating the original flue gas and then is discharged through a chimney. The stage number of the flue gas heat exchanger is determined according to the flue gas parameters, so that the purposes of utilizing waste heat and reducing energy consumption can be achieved after primary flue gas is preheated in one stage or multiple stages. The steam heater stage number is decided according to the flue gas parameter, so that the waste heat of the raw flue gas is further heated to meet the reaction temperature of the catalyst. The flue gas heat exchanger and the steam heater are installed inside the flue, so that the installation is stable, and the occupied area is reduced.

Further, the ammonia ejector is connected with an ammonia water vaporizer.

Furthermore, one path of the ammonia water vaporizer is introduced from hot air, and the other path of the ammonia water vaporizer is introduced from ammonia water.

The utility model discloses combine SNCR denitrification facility and SCR denitrification facility organically, install pot SNCR denitrification facility on furnace and make domestic waste burn burning furnace Nitrogen Oxide (NO)_X) The furnace discharge concentration is reduced to 150mg/Nm³Following, the flue gas is connected with SCR denitrification facility's flue import after desulfurization and dust removal, the utility model discloses adjusted the process behind the flue gas entering SCR denitrification facility, made former flue gas earlier carry out the heat exchange with clean flue gas, go on again after the waste heat utilization denitration, make the flue gas temperature that gets into the catalyst be in denitration catalyst ideal activity within range (200 ℃) just after the heat transfer of flue gas heating and vapour heating through waste heat utilization, the ammonia water vaporizer is through drawing from waste incinerator's hot primary airThe ammonia water is gasified into ammonia gas and then sprayed into the flue through the ammonia injector, denitration is smoothly completed under the action of the catalyst, and after the denitration clean flue gas and the original flue gas are subjected to heat exchange, the exhaust temperature of the clean flue gas is reduced and waste heat utilization is completed. Compared with the traditional equipment, the device reduces the loading of a heating device, a cooling device and a catalyst, reduces the energy consumption of the whole equipment, is more energy-saving and environment-friendly, and further reduces the production cost. SCR denitrification facility arranges on the boiler steelframe, and SCR denitration and SNCR denitration are public a reductant preparation station, and heat exchanger and flue integrated design are succinct clear, and whole pressure loss is little, reduces area.

Drawings

Fig. 1 is a schematic structural view of the present invention;

in the figure: 1. the system comprises a garbage incinerator, 2, an SNCR (selective non catalytic reduction) denitration device, 3, a first layer of spray gun, 4, a second layer of spray gun, 5, a desulfurization device, 6, a dust removal device, 7, an SCR denitration device, 8, a connecting flue, 9, an SCR inlet flue, 10, a steam heater, 11, an ammonia injector, 12, an SCR reactor, 13, a reserved layer of catalyst, 14, a first layer of catalyst, 15, a second layer of catalyst, 16, a flue gas heat exchanger, 17, an SCR outlet flue, 18, an induced draft fan, 19, a chimney and 20, an ammonia water vaporizer.

Detailed Description

The essential features of the invention will be further explained below with reference to the drawings and the detailed description of the invention.

The system for removing the ultralow emission of the nitric oxides in the household garbage incinerator comprises an SNCR denitration device 2 arranged on a hearth of the garbage incinerator 1 and an SCR denitration device 7 arranged between a dust removal device 6 and an induced draft fan 18, wherein the SNCR denitration device 2 is arranged on the hearth of the garbage incinerator 1. The outlet of the garbage incinerator 1 is connected with the inlet of a desulphurization device 5, and the outlet of the desulphurization device 5 is connected with the inlet of a dust removal device 6.

A first layer of spray guns 3 and a second layer of spray guns 4 are arranged on the SNCR denitration device 2, and the total number of the spray guns is two, and the first layer of spray guns and the second layer of spray guns are used for installing reducing agents. The first layer of spray gun is used for removing Nitrogen Oxides (NO) in the incinerator under the high-load working condition_X) The second layer of spray gun is used for removing nitrogen oxide in the incinerator under the low-load working condition(NO_X). The spray gun sprays the reducing agent ammonia water into the hearth to be atomized into particles with certain size, and the Nitrogen Oxide (NO) in the flue gas is uniformly sprayed into the hearth_X) Reducing to nitrogen and water.

The flue gas is discharged from the incinerator, passes through the desulphurization device 5 and the dust removal device 6, and then enters the SCR denitration device 7 through the connecting flue 8. The SCR denitration device 7 comprises an SCR inlet flue 9 and an SCR reactor 12, the upper part of the SCR inlet flue 9 is communicated with each other, a steam heater 10 and an ammonia injector 11 are arranged in the SCR inlet flue 9, the ammonia injector 11 is connected with an ammonia water vaporizer 20, one path of the ammonia water vaporizer 20 is introduced from hot air, and the other path of the ammonia water vaporizer is introduced from ammonia water. The ammonia water vaporizer 20 gasifies ammonia water into ammonia gas through hot primary air introduced from the garbage incinerator and then sprays the ammonia gas into a flue through an ammonia injector 11, and three catalyst installation layers are arranged in the SCR reactor 12 and are respectively used for installing a reserved layer catalyst 13, a first layer catalyst 14 and a second layer catalyst 15. And a flue gas heat exchanger 16 is arranged at the junction of the SCR inlet flue 9 and the SCR outlet flue 17. The denitrated flue gas is pressurized by a draught fan 18 and finally discharged to the atmosphere through a chimney 19.

Finally, it is also noted that the above-mentioned list is only a specific embodiment of the present invention. Obviously, the present invention is not limited to the above embodiments, and many modifications are possible. All modifications which can be derived or suggested by a person skilled in the art from the disclosure of the invention should be considered as within the scope of the invention.

Claims

1. A removal system for ultralow emission of nitric oxides of a household garbage incinerator comprises an SNCR (selective non catalytic reduction) denitration device (2) and an SCR denitration device (7), and is characterized in that the SNCR denitration device (2) is installed on a hearth of the garbage incinerator (1), the SCR denitration device (7) is installed between a dust removal device (6) and an induced draft fan (18), a flue inlet of the SCR denitration device (7) is connected with the dust removal device (6), and a flue gas heat exchanger (16) is arranged at the intersection of an SCR inlet flue (9) and an SCR outlet flue (17) of the SCR denitration device (7);

the outlet of the garbage incinerator (1) is connected with the inlet of the desulphurization device (5), and the outlet of the desulphurization device (5) is connected with the inlet of the dust removal device (6).

2. The system for removing the ultra-low emission of nitrogen oxides in the household garbage incinerator according to claim 1, characterized in that a first layer of spray guns (3) and a second layer of spray guns (4) are arranged on a hearth of the garbage incinerator (1), and the first layer of spray guns and the second layer of spray guns are used for installing reducing agents.

3. The system for removing the ultra-low emission of nitrogen oxides in the household garbage incinerator according to claim 1 or 2, characterized in that the SCR denitration device (7) is connected with the dust removal device (6) through a connecting flue (8).

4. The system for removing the ultra-low emission of nitrogen oxides in the household garbage incinerator according to the claim 1 or 2, characterized in that the SCR denitration device (7) comprises an SCR inlet flue (9) and an SCR reactor (12) which are communicated with each other at the upper part; and a steam heater (10) and an ammonia injector (11) are arranged in the SCR inlet flue (9).

5. The system for removing the ultra-low emission of nitrogen oxides in the household garbage incinerator according to the claim 4, characterized in that the SCR reactor (12) is provided with three catalyst installation layers for installing a reserved layer catalyst (13), a first layer catalyst (14) and a second layer catalyst (15).

6. The system for removing the ultra-low emission of nitrogen oxides in the household garbage incinerator according to claim 1 or 2, characterized in that the SCR outlet flue (17) is connected with a chimney (19) through an induced draft fan (18).

7. The system for removing ultra-low emission of nitrogen oxides in a household garbage incinerator according to claim 4, characterized in that the ammonia ejector (11) is connected with an ammonia water vaporizer (20).

8. The system for removing the ultra-low emission of nitrogen oxides in the household garbage incinerator according to the claim 7, characterized in that the ammonia water vaporizer (20) is introduced from hot air in one path and from ammonia water in the other path.