CN205014343U

CN205014343U - W flame boiler

Info

Publication number: CN205014343U
Application number: CN201520787214.8U
Authority: CN
Inventors: 汪毅刚
Original assignee: DATANG HUAYIN ZHUZHOU POWER GENERATION Co Ltd
Current assignee: DATANG HUAYIN ZHUZHOU POWER GENERATION Co Ltd
Priority date: 2015-10-12
Filing date: 2015-10-12
Publication date: 2016-02-03
Anticipated expiration: 2025-10-12

Abstract

The utility model discloses a W flame boiler, include upper and lower furnace and bispin dryer disconnect -type coal burner, secondary wind box. Coal burner arranges under in before the furnace, on the hunch of back wall, preceding, the back wall outside that two secondary wind box arranged under in furnace respectively from encircle go up and encircle under blow in furnace, furnace is kicked into down respectively to a wind getting into each coal burner after power stream tuber pipe and weary gas tuber pipe pass secondary wind box in. The messenger arranges that the regional coal burner in furnace width direction middle part only blows the buggy through the power stream tuber pipe in furnace under in, and the increased pressure of power jet department will make the down stroke degree of depth of a wind strengthen, makes the cinder position of firing of buggy put to move down and make burning center and temperature level in the furnace descend, prevents the weary gas tuber pipe scaling loss of combustor, reduction forced draught blower outlet pressure, increase air supply volume, make the buggy fully burn in order to improve boiler efficiency to sending into the overgrate air in the middle part of the furnace width direction under high load condition simultaneously.

Description

W flame boiler

Technical field

The utility model relates to a kind of W type flame boiler, is specifically related to a kind of burner hearth air-supply structure of W type flame boiler.

Background technology

The major technique of W type flame boiler is that wall with refractory lining, refracto and Pulverized Coal Concentration burner are laid in combustion chamber.W type flame hearth is made up of lower combustion chamber and top cooling chamber, lower combustion chamber volume enlargement about a times, and fuel combustion process is carry out in lower combustion indoor substantially.Have a waisting between upper lower hearth, burner arrangement is on waisting, and breeze airflow is from the vault Jet with downward flow direction of waisting, and ignition.Pulverized coal particle weight saving after breeze airflow after catching fire to lower furnace portion, now flame is subject to the picking-up effect of bottom, combustion chamber classification wind, flowing of upwards transferring, at lower combustion indoor formation W type flame.

The air port of Secondary Air from arch and under arch of W type flame boiler enters burner hearth, generally be arranged in lower hearth 70% of secondary air flow, and the burnt zone of coal dust is in upper furnace, makes the later stage for hypoxgia like this, coal dust burns stage anoxic and burns insufficient, reduces boiler efficiency.Certain research institutions once carried out scientific research project " burnt wind transformation " in company's cooperation, sent into Secondary Air from arch, but because Secondary Air rigidity is inadequate and spout cooling problem cannot solve, caused weary gas airduct to burn out, finally well do not applied.

Utility model content

The purpose of this utility model is to provide a kind of raising to utilize weary gas airduct to send into Secondary Air while burner main injection jet First air rigidity in the middle part of furnace chamber width, extend the kinetic energy of main breeze airflow undershoot, prevent breeze airflow short circuit from turning in advance, extend the coal dust firing time, improve W type flame boiler efficiency of combustion.

The utility model discloses a kind of W flame boiler, comprise upper furnace, lower hearth and bispin air duct separate type coal burner, secondary air box.Some coal burners are arranged on the arch of lower hearth front wall and rear wall, outside the front wall that two secondary air box are arranged in lower hearth respectively and rear wall, blow from arch and under arch respectively by air port in two ends in burner hearth, enter the effect of First air by cyclonic separation of each coal burner, the weary gas jet of the power stream and dilute phase that are divided into concentrated phase is injected in lower hearth through after secondary air box through power stream airduct and weary gas airduct respectively.The described coal burner being arranged in lower hearth width central region blows coal dust by means of only power stream airduct in burner hearth, controls the First air entered in this each region coal burner and all enters in power stream airduct.

Described secondary air box corresponding lower hearth width central region is connected with the secondary air channel identical with described weary gas airduct direction and encircles lower air-supply toward burner hearth.

The described weary gas airduct being arranged in the described coal burner of lower hearth width central region is communicated with described secondary air box blows under burner hearth encircles.

The utility model makes to enter the First air be arranged in furnace chamber width central region coal burner and all enters in power stream airduct blow coal dust in burner hearth, the pressure increase of nozzle strengthens making the undershoot degree of depth of First air, the position, burnt zone of coal dust is moved down the temperature levels in combustion centre and burner hearth is declined, prevent the weary gas airduct scaling loss of burner, reduce pressure fan outlet pressure, increase air output; Under high load capacity operating mode, send into Secondary Air simultaneously carry out the amount of oxygen of coal powder ignition burning needed for the later stage in the middle part of supplementary furnace chamber width, make coal dust energy Thorough combustion as far as possible, thus improve boiler efficiency.During coal dust firing, be highest temperature area in the middle part of burner hearth, and the secondary wind pressure sent into is about 1/10th of primary air pressure, on the ignition of coal dust without any impact.

Accompanying drawing explanation

Fig. 1 is the structural representation of the utility model embodiment.

Fig. 2 is the A-A schematic diagram in Fig. 1.

Fig. 3 is the improved structural representation of coal burner weary gas airduct in the middle part of furnace chamber width.

Detailed description of the invention

The present embodiment is transformation W flame boiler (310MW) in use.

As shown in Figure 1 and Figure 2, this W flame boiler of the present embodiment application, comprises upper furnace 1, lower hearth 2, bispin air duct separate type coal burner 3 and secondary air box 4.The arch of lower hearth 2 front wall and rear wall is staggered in arrangement respectively outside front wall and rear wall that 12 bispin air duct separate type coal burners, 3, two secondary air box 4 are arranged in lower hearth 2 respectively, two ends respectively by air port from arch and arch time blow in burner hearth.

The design feature of bispin air duct separate type coal burner 3 makes to enter the effect of the First air in it by cyclonic separation, the weary gas jet of the power stream and dilute phase that are divided into concentrated phase is injected in lower hearth 2 through power stream airduct 31 and weary gas airduct 32 respectively, and power stream airduct 31 and weary gas airduct 32 are each passed through secondary air box 4.

Blow in lower hearth 2 respectively by air port in the two ends of each secondary air box 4,12 unit are divided into baffle plate in its inner chamber, corresponding each bispin air duct separate type coal burner 3 is a unit, each cell layout a, b, c, d, e, f six groups of secondary air dampers, the wherein secondary air flow of a, b, c baffle controls arch upper part, the secondary air flow of d, e, f baffle controls arch lower part.

As shown in Figure 2, the bispin air duct separate type coal burner being arranged in lower hearth 2 front wall and rear wall width central region is respectively B3, A3, D3, C3 and C6, D6, A6, B6.

As shown in Figure 3, because the weary gas airduct of bispin air duct separate type coal burner is arranged in the central side by burner hearth, and containing the easy short circuit of fine breeze in weary gas, affect after-flame effect; The weary gas wind of lower temperature be arranged in First air air-flow to fiery side, hinder the heat and mass of main breeze airflow and high temperature recirculation zone, have impact on the ignition of breeze airflow.So transform the weary gas airduct of these burners: by the partial cutaway of weary gas airduct through secondary air box inner chamber, then the pipeline section be positioned on the upside of secondary air box is closed, retain lower tubular section and send into Secondary Air in burner hearth.

After transformation, the First air entered in the middle part of furnace chamber width in these burners all enters in its power stream airduct coal dust to blow and enters in lower hearth, the pressure increase of power stream airduct nozzle makes the undershoot degree of depth of First air strengthen, the position, burnt zone of coal dust is moved down the temperature levels in combustion centre and burner hearth is declined, prevent the weary gas airduct scaling loss of burner, reduce pressure fan outlet pressure, increase air output; Under high load capacity operating mode, send into Secondary Air simultaneously carry out the amount of oxygen of coal powder ignition burning needed for the later stage in the middle part of supplementary furnace chamber width, make coal dust energy Thorough combustion as far as possible, thus improve boiler efficiency.During coal dust firing, be highest temperature area in the middle part of burner hearth, and the secondary wind pressure sent into is about 1/10th of primary air pressure, on the ignition of coal dust without any impact.

Corresponding front wall C6, D6, A6, B6, the improved effect of weary gas airduct of rear wall B3, A3, D3, C3 burner is as follows: under 300MW load during a, b, c baffle plate standard-sized sheet on corresponding secondary air box top, furnace outlet gas temperature reduces about 13 DEG C, the maximum reduction of superheater tube wall temperature about 30 DEG C, the maximum reduction of reheater tube wall temperature about 10 DEG C, spray water flux decreases about 29t/h, meanwhile, unburned carbon in flue dust also has obvious reduction, be reduced to 2.80% by 4.35%, reducing amplitude is about 1.6%.The pressure fan main-piping pressure 0.1kPa that has an appointment reduces (amplitude), pressure fan safe operation when being conducive at full capacity.According to the reference value that fired power generating unit various factors affects net coal consumption rate, fly ash combustible material often reduces 1g/KWh, affects net coal consumption rate and reduces 1.23g/KWh.Net coal consumption rate 1.96g/KWh is reduced after the anoxic Optimizing Reconstruction of middle part under W flame boiler high load capacity operating mode.About annual utilization hours calculated by 4000 hours, saved fuel cost 1,600,000 yuan.

Claims

1. a W flame boiler, comprise, lower hearth and bispin air duct separate type coal burner, secondary air box, some coal burners are arranged on the arch of lower hearth front wall and rear wall, outside the front wall that two secondary air box are arranged in lower hearth respectively and rear wall, blow from arch and under arch respectively by air port in two ends in burner hearth, enter the effect of First air by cyclonic separation of each coal burner, the weary gas jet of the power stream and dilute phase that are divided into concentrated phase is injected in lower hearth through power stream airduct and weary gas airduct through after secondary air box respectively, it is characterized in that: the described coal burner being arranged in lower hearth width central region blows coal dust by means of only power stream airduct in burner hearth, control the First air entered in each coal burner in this region all to enter in power stream airduct.

2. W flame boiler as claimed in claim 1, is characterized in that: described secondary air box corresponding lower hearth width central region is connected with the secondary air channel identical with described weary gas airduct direction and encircles lower air-supply toward burner hearth.

3. W flame boiler as claimed in claim 1, is characterized in that: described in be arranged in the described coal burner of lower hearth width central region weary gas airduct is communicated with past burner hearth with described secondary air box and encircles and time to blow.