阅读说明：本技术 一种低氮锅壳式锅炉 (Low-nitrogen pot type boiler ) 是由 楼宇 王宁 胡锐 王爱铭 苏富强 刘兴照 杨敬尧 于 2019-09-11 设计创作，主要内容包括：本发明公开了一种低氮锅壳式锅炉,主要包括炉胆、转烟室、烟管、锅壳、前烟箱、省煤器、燃烧器、CEMS烟气在线监测系统、脱硝温度测点和脱硝还原剂喷射装置,锅壳内横置有炉胆和烟管,锅壳的后部设置有转烟室,转烟室采用膜式壁结构形成导流膜式壁并与炉胆相连通使能燃料在炉胆内完全燃烧后产生的烟气进入转烟室。本发明的有益效果为：锅炉后部设置了容积较大的转烟室,转烟室采用膜式壁结构。锅炉转烟室中设置了温度传感器和脱硝还原剂喷射装置。通过对烟气温度的检测,可以确保脱硝还原剂在最佳温度区间内工作,提高脱硝效率。锅炉转烟室中设置了导流膜式壁,延长了流程,可以确保脱硝还原剂与烟气能充分有效地接触混合,提升脱硝效率。(The invention discloses a low-nitrogen pot-type boiler which mainly comprises a furnace pipe, a smoke transfer chamber, a smoke pipe, a pot shell, a front smoke box, an economizer, a burner, a CEMS smoke on-line monitoring system, a denitration temperature measuring point and a denitration reducing agent injection device, wherein the furnace pipe and the smoke pipe are transversely arranged in the pot shell, the smoke transfer chamber is arranged at the rear part of the pot shell, and the smoke transfer chamber adopts a membrane wall structure to form a diversion membrane wall and is communicated with the furnace pipe so that smoke generated after fuel is completely combusted in the furnace pipe enters the smoke transfer chamber. The invention has the beneficial effects that: the rear part of the boiler is provided with a smoke-turning chamber with larger volume, and the smoke-turning chamber adopts a membrane wall structure. A temperature sensor and a denitration reducing agent injection device are arranged in the boiler smoke transfer chamber. Through the detection to the flue gas temperature, can ensure that the denitration reductant works in the optimum temperature interval, improve denitration efficiency. The guide membrane type wall is arranged in the boiler smoke transfer chamber, the flow is prolonged, the denitration reducing agent and the smoke can be fully and effectively contacted and mixed, and the denitration efficiency is improved.)

1. A low-nitrogen shell type boiler is characterized in that: the denitration device mainly comprises a furnace pipe (1), a smoke transfer chamber (2), a smoke pipe (3), a pot shell (4), a front smoke box (5), an economizer (6), a burner (7), a CEMS smoke on-line monitoring system (8), a denitration temperature measuring point (9) and a denitration reducing agent injection device (10), wherein the furnace pipe (1) and the smoke pipe (3) are transversely arranged in the pot shell (4), the smoke transfer chamber (2) is arranged at the rear part of the pot shell (4), and the smoke transfer chamber (2) adopts a membrane wall structure to form a flow guide membrane type wall (11) and is communicated with the furnace pipe (1) so that smoke generated after fuel is completely combusted in the furnace pipe (1) enters the smoke transfer chamber (2); the denitration device is characterized in that temperature sensors are arranged on the smoke transfer chamber (2) to form denitration temperature measuring points (9), a denitration reducing agent injection device (10) is arranged near each temperature sensor, and the denitration reducing agent is sprayed in high-temperature smoke through the denitration reducing agent injection device (10) to reduce the emission of nitrogen oxides.

2. A low nitrogen shell boiler as claimed in claim 1, characterized in that: the denitration reducing agent is ammonia water or urea.

3. A low nitrogen shell boiler as claimed in claim 1, characterized in that: the CEMS flue gas on-line monitoring system (8) monitors the content of nitric oxide in flue gas at the rear part of the boiler in real time, and the amount of the sprayed denitration reducing agent is adjusted through the control system.

4. A low nitrogen shell boiler as claimed in claim 1, characterized in that: the denitration reducing agent injection device is characterized in that a cavity (12) is arranged outside the smoke transfer chamber (2), the temperature sensor and the denitration reducing agent injection device (10) are installed in the cavity (12) and extend into the smoke transfer chamber (2), the denitration reducing agent injection device (10) adopts a telescopic structure, and the insertion depth of the denitration reducing agent injection device (10) is automatically adjusted according to the calculation result of the CEMS smoke online monitoring system (8).

5. A low nitrogen shell boiler as claimed in claim 1 or 4, characterized in that: the smoke rotating chamber (2) is provided with an observation hole and a manhole.

Technical Field

The invention relates to the field of boilers, in particular to a low-nitrogen shell type boiler.

Background

In recent years, with the rapid development of economy in China and the deep promotion of industrialization and urbanization, the consumption of energy sources is continuously increased. Meanwhile, the problem of air pollution is increasingly prominent, and the air quality of some cities is gradually deteriorated, so that the urban air pollution becomes the most severe environmental problem in China. If practical and effective measures are not taken to prevent further deterioration of the ecological environment, the environmental problems can restrict the sustainable, rapid and healthy development of the economy in China.

Nitrogen oxides produced during the combustion of fuel are important factors affecting the quality of ambient air. The industrial boiler is a large energy consumer, and how to reduce the emission of nitrogen oxides in boiler flue gas is the research and development focus of current boiler manufacturers. The emission of nitrogen oxides can be greatly reduced by adopting low-nitrogen technologies such as flue gas recirculation and staged combustion for a natural gas fuel boiler, but the emission of nitrogen oxides cannot be obviously reduced by utilizing the technologies such as flue gas recirculation and staged combustion for light diesel fuel and pyrolysis gas fuel (biomass gasification fuel and the like containing a large amount of impurities such as nitrogen).

Disclosure of Invention

The invention aims to overcome the defects in the prior art, and provides a low-nitrogen shell type boiler which can greatly reduce the emission of nitrogen oxides in flue gas by using a denitration technology.

The object of the present invention is achieved by the following technical means. A low-nitrogen pot-type boiler mainly comprises a furnace pipe, a smoke transfer chamber, a smoke pipe, a pot shell, a front smoke box, an economizer, a burner, a CEMS smoke on-line monitoring system, a denitration temperature measuring point and a denitration reducing agent injection device, wherein the furnace pipe and the smoke pipe are transversely arranged in the pot shell, the smoke transfer chamber is arranged at the rear part of the pot shell, a membrane wall structure is adopted in the smoke transfer chamber to form a diversion membrane wall, and the diversion membrane wall is communicated with the furnace pipe to enable smoke generated after fuel is completely combusted in the furnace pipe to enter the smoke transfer chamber; the denitration device is characterized in that the smoke transfer chamber is provided with temperature sensors to form denitration temperature measuring points, a denitration reducing agent injection device is arranged near each temperature sensor, and the denitration reducing agent injection device sprays denitration reducing agents in high-temperature smoke to reduce emission of nitrogen oxides.

The denitration reducing agent is ammonia water or urea.

The CEMS flue gas on-line monitoring system monitors the content of nitric oxide in flue gas at the rear part of the boiler in real time, and adjusts the amount of the sprayed denitration reducing agent through the control system.

The flue gas conversion chamber is provided with a cavity, the temperature sensor and the denitration reducing agent injection device are arranged in the cavity and extend into the flue gas conversion chamber, the denitration reducing agent injection device adopts a telescopic structure, and the insertion depth of the denitration reducing agent injection device is automatically adjusted according to the calculation result of the CEMS flue gas online monitoring system 8.

The smoke chamber is provided with an observation hole and a manhole.

The invention has the beneficial effects that:

1. in the invention, the shell type boiler adopts a large furnace pipe structure, the rear part of the boiler is provided with a smoke-transferring chamber with larger volume, and the smoke-transferring chamber adopts a membrane wall structure. The fuel is completely combusted in the furnace pipe, and the temperature of the smoke entering the smoke transferring chamber can be controlled within the range of 850-1050 ℃.

2. In the invention, a temperature sensor and a denitration reducing agent injection device are arranged in a smoke transfer chamber of the boiler. Through the detection to the flue gas temperature, can ensure that denitration reductant works in the best temperature interval (800 ~ 1100 ℃), improve denitration efficiency.

3. According to the invention, the guide membrane type wall is arranged in the boiler smoke transfer chamber, so that the flow is prolonged, the denitration reducing agent and the smoke can be fully and effectively contacted and mixed, and the denitration efficiency is improved.

4. The invention is suitable for fuels with different fuel components and different heat values, and comprises the following components: light diesel oil, biomass gas, blast furnace gas, coke oven gas and the like, and is also applicable to natural gas.

5. In the invention, ammonia water or urea is sprayed in high-temperature flue gas by adopting an NSCR denitration technology.

6. In the invention, the CEMS flue gas online analysis system monitors the content of nitric oxide in the flue gas at the tail part of the boiler in real time, and the amount of the sprayed denitration reducing agent is adjusted by the control system.

7. In the invention, the boiler smoke transfer chamber is provided with the observation hole and the manhole, so that the observation and the maintenance in the boiler can be conveniently checked at any time when the running state in the boiler is checked or the boiler enters the boiler during blowing out.

Drawings

FIG. 1 is a schematic structural diagram of the present invention.

FIG. 2 is a schematic diagram of a denitration structure of a film-type wall structure smoke-transferring chamber.

FIG. 3 is a schematic block diagram of a real-time online denitration adjustment control system.

Description of reference numerals: the device comprises a furnace pipe 1, a smoke transfer chamber 2, a smoke pipe 3, a boiler shell 4, a front smoke box 5, an economizer 6, a burner 7, a CEMS smoke on-line monitoring system 8, a denitration temperature measuring point 9, a denitration reducing agent injection device 10, a guide membrane type wall 11 and a cavity 12.

Detailed Description

The invention will be described in detail below with reference to the following drawings:

as shown in fig. 1-2, a low-nitrogen shell-type boiler mainly comprises a boiler furnace 1, a smoke transfer chamber 2, a smoke pipe 3, a boiler shell 4, a front smoke box 5, an economizer 6, a burner 7, a CEMS smoke on-line monitoring system 8, a denitration temperature measuring point 9 and a denitration reducing agent injection device 10, wherein the boiler furnace 1 and the smoke pipe 3 are transversely arranged in the boiler shell 4, the smoke transfer chamber 2 is arranged at the rear part of the boiler shell 4, and the smoke transfer chamber 2 adopts a membrane wall structure to form a flow guide membrane wall 11 and is communicated with the boiler furnace 1 so that smoke generated after fuel is completely combusted in the boiler furnace 1 enters the smoke transfer chamber 2; the flue gas conversion chamber 2 is provided with temperature sensors to form denitration temperature measuring points 9, a denitration reducing agent injection device 10 is arranged near each temperature sensor, and the denitration reducing agent is sprayed in high-temperature flue gas through the denitration reducing agent injection device 10 to reduce the emission of nitrogen oxides. The outer of the smoke-turning chamber 2 is provided with a cavity 12, and the smoke-turning chamber 2 is also provided with an observation hole and a manhole. The temperature sensor and the denitration reducing agent injection device 10 are installed in the cavity 12 and extend into the smoke transfer chamber 2, the denitration reducing agent injection device 10 adopts a telescopic structure to form a spray gun depth adjusting system, and the insertion depth of the denitration reducing agent injection device 10 is automatically adjusted according to the calculation result of the CEMS smoke online monitoring system 8.

In this example, the fuel is completely burned in the furnace of the shell-and-pan boiler, and the high-temperature flue gas enters the smoke-transferring chamber of the membrane wall structure. The smoke transfer chamber is provided with a guide membrane type wall to form a semi-wet back type structure, so that the smoke flow can be properly prolonged; when the increase heated surface, also enlarged the denitration space, made the abundant effectual contact of denitration catalyst and flue gas, promoted denitration efficiency. According to the invention, an NSCR denitration technology is adopted, and ammonia water or urea is sprayed in high-temperature flue gas; then the flue gas enters a smoke pipe and an economizer for further cooling, and finally is discharged into the atmosphere.

In this example, the temperature sensor is arranged in the boiler smoke transfer chamber, so that the smoke temperature at the position can be detected at any time and fed back to the boiler control system, and the smoke temperature at the spraying position of the reducing agent can be ensured to be in the optimal denitration reaction temperature range (generally 800-1100 ℃, and the reaction temperature can be specifically selected according to the difference of the reducing agent) by adjusting combustion and other modes.

In this embodiment, equipped with CEMS flue gas on-line analysis system for the content of nitrogen oxide in the monitoring boiler afterbody flue gas, and feedback signal reaches denitration control system, the medicament quantity that the reducing agent sprays is convenient for in time adjust. Set up denitrification facility in the membrane type wall structure, including program carriers such as a plurality of temperature measurement stations and denitration nozzle and corresponding control valve, instrument along flue gas flow direction, the membrane type wall is fired the room and is had obvious temperature distribution on the flue gas flow, guarantees that denitration catalyst sprays into in the optimum temperature region all the time, sprays the quantity governing system and includes pump (adjustable), adjusting valve (have actuating mechanism or manual structure), multichannel spraying pipe way.

In this embodiment, the processor outputs the resulting signal to the lance depth adjustment system. And the spray gun depth adjusting system automatically adjusts the insertion depth of the spray gun according to the result calculated by the main control room PC. The unused spray point spray gun can be withdrawn from the furnace, so that high-temperature flue gas is prevented from being washed away, and the service life of the spray gun is prolonged. The processor outputs the obtained signal to the spraying amount adjusting system. The spraying amount adjusting system automatically adjusts the opening of an ammonia or urea pipeline adjusting valve or the rotating speed of a pump according to the result calculated by the main control room PC.

In this embodiment, diaphragm type wall structure changes smoke chamber and is provided with observation hole and manhole, makes things convenient for the staff to look over the interior running state of stove at any time to and get into in the stove and observe and maintain during the blowing out, avoid because the boiler tobacco pipe that tar problem and urea powder etc. caused blocks up.

It should be understood that equivalent substitutions and changes to the technical solution and the inventive concept of the present invention should be made by those skilled in the art to the protection scope of the appended claims.