阅读说明：本技术 一种用于四角切圆燃煤锅炉的贴壁风系统 (Wall-attached air system for coal-fired boiler with four tangential corners ) 是由 任立立 孙锐 果志明 邸艳龙 赵春辉 吴政刚 葛尧 宫艳欣 于 2019-11-19 设计创作，主要内容包括：一种用于四角切圆燃煤锅炉的贴壁风系统,属于锅炉技术领域,以解决现有锅炉水冷壁的高温腐蚀问题及结焦问题,和现有的贴壁风系统存在的喷口容易结焦堵塞,喷口出风方向与炉内主燃烧切圆无法协调,贴壁风调节机制单一,无法跟随燃烧及壁面气氛的变化对贴壁风量进行局部调节的问题。本发明包括风箱、调节风门、风压差测量装置和贴壁风喷管；锅炉炉墙的四周面分别设置有多行多列贴壁风喷管,每个贴壁风喷管伸入到炉膛内,每个贴壁风喷管的入口端均设置有贴壁风调节管,每个贴壁风调节管上设置有风压差测量装置,每个贴壁风调节管与风箱连通,每个贴壁风喷管上均设置有一个调节风门,每个贴壁风喷管的喷口方向与锅炉内对应烟气流场的切线方向相同。(The utility model provides a wall-attached air system for four corners tangential coal fired boiler, belongs to boiler technical field to solve the high temperature corrosion problem and the coking problem of current boiler water-cooled wall, the spout easy coking that exists with current wall-attached air system blocks up, and spout air-out direction and the interior main burning tangential of stove can't coordinate, and wall-attached air regulation mechanism is single, can't follow the problem that burning and wall atmosphere's change carry out local regulation to the wall-attached air volume. The invention comprises an air box, an air adjusting door, an air pressure difference measuring device and an adherence air nozzle; the peripheral face of boiler brickwork is provided with multirow multiseriate adherence wind spray tube respectively, every adherence wind spray tube stretches into in the furnace, the entry end of every adherence wind spray tube all is provided with adherence wind adjusting pipe, be provided with wind pressure differential measuring device on every adherence wind adjusting pipe, every adherence wind adjusting pipe and bellows intercommunication all are provided with an air damper on every adherence wind spray tube, the spout direction of every adherence wind spray tube is the same with the tangential direction who corresponds flue gas flow field in the boiler.)

1. The utility model provides an adherence wind system for four corners tangential coal fired boiler which characterized in that: the device comprises an air box (1), an air adjusting door (2), an air pressure difference measuring device (6) and an adherence air nozzle (3);

the all around face of boiler brickwork (4) is provided with multirow multiseriate adherence wind spray tube (3) respectively, every adherence wind spray tube (3) stretches into in the furnace, the entry end of every adherence wind spray tube (3) all is provided with adherence wind adjusting pipe (5), be provided with on every adherence wind adjusting pipe (5) wind pressure differential measuring device (6), every adherence wind adjusting pipe (5) and bellows (1) intercommunication, all be provided with one air damper (2) on every adherence wind spray tube (3), the spout direction of every adherence wind spray tube (3) is the same with the tangential direction who corresponds the flue gas flow field in the boiler, bellows (1) are fixed on boiler brickwork (4).

2. The adherent air system for a corner tangential coal fired boiler of claim 1, wherein: the included angle between each adherence wind nozzle (3) and the horizontal plane is 0-60 degrees.

3. An adherent air system for a corner tangential firing coal fired boiler according to claim 1 or 2 wherein: every adherence wind spray tube (3) is 0 ~ 90 with the contained angle of boiler furnace wall (4) and the plane of horizontal plane vertical respectively.

4. The adherent air system for a corner tangential coal fired boiler of claim 1, wherein: the wall-attached air spray pipes (3) are arranged at an angle and a position on each side surface of the boiler wall (4) according to requirements.

5. The adherent air system for a corner tangential coal fired boiler of claim 1, wherein: each wall-mounted air spray pipe (3) is provided with a fire-watching coking hole (3-1).

6. The adherent air system for a corner tangential coal fired boiler of claim 1, wherein: each air pressure difference measuring device (6) comprises a pressure transformer (6-1) and two symmetrical air inlet pipes (6-2);

two symmetrical air inlet pipes (6-2) are inserted into each adherence air adjusting pipe (5), air inlets of the two symmetrical air inlet pipes (6-2) are inclined openings, one inclined opening faces to the windward side, the other inclined opening faces to the leeward side, and air outlets of the two air inlet pipes (6-2) are connected with the pressure changer (6-1).

7. The adherent air system for a corner tangential coal fired boiler of claim 1, wherein: each air pressure difference measuring device (6) comprises a U-shaped glass tube (6-3) and two symmetrical air inlet tubes (6-2);

two symmetrical air inlet pipes (6-2) are inserted into each adherence air adjusting pipe (5), air inlets of the two symmetrical air inlet pipes (6-2) are oblique openings, one of the oblique openings faces the windward side, the other oblique opening faces the leeward side, air outlets of the two air inlet pipes (6-2) are respectively connected with two ports of a U-shaped glass pipe (6-3), and water is filled in the U-shaped glass pipe (6-3).

Technical Field

The invention relates to a boiler, in particular to an adherence air system for a coal-fired boiler with four tangential corners.

Background

The thermal equipment is used as a core component of a thermal power plant, and the thermal power plant can safely, reliably and economically operate. Utility boilers, as a typical thermal device in thermal power plants, play an important role in the power generation process. For a long time, due to the influence of market factors, coal quality for burning of power station boilers in China is relatively miscellaneous, a certain deviation often exists between the coal quality and the characteristics of designed fuel, and frequent change occurs, so that a series of problems are brought, and the reliability and the economy of the operation of the power station boilers are seriously influenced. The frequent change of coal quality and unreasonable blending and burning of coal blending often cause problems of slagging, contamination, high-temperature corrosion and the like, wherein the high-temperature corrosion problem has the greatest influence on the operational reliability of the boiler, and the high-temperature corrosion often interacts and promotes with the slagging and the contamination.

The existing method for eliminating high-temperature corrosion of a boiler mainly aims to improve the reducing atmosphere of the wall surface, and air flow is sprayed into a water-cooled wall in an adherence mode in a region where high-temperature corrosion easily occurs to form an oxidizing gas film. The existing implementation technologies can be generally divided into three technical routes.

Firstly, a conventional horizontal T-shaped wall-attached air device is added on a water-cooled wall surface, and air outlets are horizontally arranged. The wall-attached wind device and the arrangement mode thereof mainly have the following defects: the air outlet direction of the nozzle cannot be coordinated with the main combustion tangent circle in the furnace, and the adherence air is blown away by the combustion air flow in the furnace after flowing into the furnace along the counter-wind direction, so that the upstream water-cooled wall cannot be protected; the wall-attached air system has no feedback and regulation mechanism and cannot regulate wall-attached air quantity along with the change of combustion and wall surface atmosphere; the nozzle is easy to coke and block, so that the wall-attached air nozzle loses the function.

Secondly, a conventional vertical wall-attached air device is added on the water-cooled wall surface, and an air outlet is vertically arranged as in patent CN 205717307U, so that the wall-attached air device and the arrangement mode thereof mainly have the following defects: because the air outlet direction of the nozzle is vertical to the combustion air flow, the air flow in the boiler horizontally rotates and rises, and no horizontal momentum exists after the adherence air enters the boiler, the adherence air flow can immediately drift along with the combustion air flow in the boiler, and the protection with enough area can not be formed on the near wall surface of the water-cooled wall; the wall-attached air adjusting mechanism is single, and the wall-attached air quantity cannot be locally adjusted along with the change of combustion and wall surface atmosphere; the nozzle is easy to coke and block, so that the wall-attached air nozzle loses the function.

Thirdly, the horizontal wall-attached air nozzles at the corners are adopted, the air outlets are arranged near the corner burners, and the wall-attached air device and the arrangement mode thereof mainly have the following defects: because the direction of the outlet air of the nozzle is vertical, and the patent CN 203421675U mainly has the following disadvantages: the oxidizing gas film cannot cover all high-temperature corrosion areas when the oxidizing gas film is arranged close to the corner; the air quantity is not adjustable, and the air quantity passively changes along with the air quantity of secondary air (primary air peripheral air); the nozzle is easy to coke and block, so that the wall-attached air nozzle loses the function.

Disclosure of Invention

In order to solve the problems, the invention provides an adherent air system for a coal-fired boiler with four tangential corners.

The technical scheme adopted by the invention for solving the technical problems is as follows:

the device comprises an air box, an air adjusting door, an air pressure difference measuring device and an adherence air nozzle;

the peripheral face of boiler brickwork is provided with multirow multiseriate adherence wind spray tube respectively, every adherence wind spray tube stretch into furnace in and with the central line MN parallel and level of the water-cooling wall of boiler, the entry end of every adherence wind spray tube all is provided with adherence wind adjusting pipe, be provided with wind pressure differential measuring device on every adherence wind adjusting pipe, every adherence wind adjusting pipe and bellows intercommunication, all be provided with an air damper on every adherence wind spray tube, the spout direction of every adherence wind spray tube is the same with the tangential direction who corresponds the flue gas flow field in the boiler, bellows are fixed on boiler brickwork.

Furthermore, each wall-attached air spray pipe is provided with a fire-watching coking hole.

Furthermore, each air pressure difference measuring device comprises a pressure transformer and two symmetrical air inlet pipes;

two symmetrical air inlet pipes are inserted into each wall-mounted air adjusting pipe, air inlets of the two symmetrical air inlet pipes are inclined openings, one inclined opening faces to the windward side, the other inclined opening faces to the leeward side, and air outlets of the two air inlet pipes are connected with a pressure changer.

Compared with the prior art, the invention has the following beneficial effects:

the nozzle direction of each adherence air spray pipe is the same as the tangential direction of combustion air flow in a boiler, an oxidation air film is formed on the surface of a water-cooled wall along with the rotation of the combustion air flow in the boiler, and each adherence air spray pipe is provided with a damper which can regulate the whole or local air volume of adherence air according to the intensity of the combustion air flow in the boiler so that the air flow blown into the boiler by each adherence air pipe has certain intensity and is not blown away by the combustion rotation air flow, the adherence air is ensured to form the oxidation air film on the surface of the water-cooled wall, meanwhile, the formation of the oxidation air film also prevents the washing and high-temperature corrosion of the combustion particles in the boiler on the water-cooled wall through the rotation air flow, and the low-nitrogen combustion effect in the boiler can be prevented by controlling the air quantity entering the boiler by each adherence air.

And secondly, each adherence air adjusting pipe is provided with an air pressure difference measuring device, the pressure difference between the leeward side and the windward side of the adherence air adjusting pipe is obtained through the height change of a water column in a pressure transmitter or a U-shaped pipe, the air speed of the adherence air adjusting pipe is obtained through calculation, and the adjusting air door on each lift wall air nozzle is adjusted in a targeted manner according to the air speed.

And each wall lifting air nozzle is provided with a fire observation hole and a coking hole, so that the safe and reliable operation of the equipment is ensured, and the blocking and burning risks of the wall lifting air nozzles are reduced.

Drawings

FIG. 1 is a schematic view of the present invention;

FIG. 2 is a top view of FIG. 1;

FIG. 3 is a schematic view of the attachment of adherent air lances 3 to boiler furnace walls 4;

FIG. 4 is a schematic view of a wind pressure difference measuring device 6 on the adherent wind adjusting pipe 5;

fig. 5 is a schematic view of another wind pressure difference measuring device 6 on the adherent wind adjusting pipe 5;

FIG. 6 is a graph of a simulation of the oxygen content of the surface of the boiler wall 4 when the wall-attached air is not tangential to the combustion air flow;

FIG. 7 is a graph of a numerical simulation of the oxygen content of the surface of the boiler furnace wall 4 with wall wind tangential to the combustion gas flow.

Detailed Description