CN101074774A

CN101074774A - Bi-spiral flow smokeless steam boiler with chain grates

Info

Publication number: CN101074774A
Application number: CN 200710015965
Authority: CN
Inventors: 王树洲
Original assignee: Individual
Current assignee: Individual
Priority date: 2007-06-16
Filing date: 2007-06-16
Publication date: 2007-11-21

Abstract

The invention relates to a chain grate and double swirl smokeless steam boiler, a thermal equipment, including shell, water wall, convection of the group, the drum and lower coal-fired devices, the coal-fired device includes coal installation, chain grate , the front furnace arch and the back furnace arch on the coal-fired, between the front arch and a chain grate constitute the front hearth, between the back furnace arch and the chain grate constitute back hearth, between the front furnace arch and the back furnace arch have the combustion gas export, the front hearth fall into upper hearth and nether hearth ,and its cross-section present two symmetry R form structure, the nether hearth of the two R form front hearth communicate, on the front hearth side wall has a tuyere open into upper hearth , the back of the front hearth connect the combustion gas export. The structure is simple reasonable, and low cost, full combustion, high thermal efficiency, low energy consumption, solved black smoke fouling problems, protection of the environment.

Description

Bi-spiral flow smokeless steam boiler with chain grates

Technical field

The present invention relates to a kind of bi-spiral flow smokeless steam boiler with chain grates, belong to Thermal Equipment.

Background technology

At present, large-scale traveling-grate stoker formula steam boiler, widelyd popularize at home and performance is advanced belongs to SZL type series of products, structure comprises shell, water-cooling wall, the convection tube group, the coal-burning installation of drum and bottom, coal-burning installation comprises coaling gear, traveling-grate stoker, trimmer arch and stove rear arch, constitute front furnace between trimmer arch and the traveling-grate stoker, constitute rear hearth between stove rear arch and the traveling-grate stoker, the outlet of combustion heat gas is arranged between trimmer arch and the stove rear arch, thermal power 4.2MW-30MW, even bigger, typing drawing and manufacturing inspection standard that each cauldron factory all has national Ministry of Labour to issue.

Although during these product designs, " pot " has enough heating surfaces, but because the wrong vertical complicated a large amount of dust stratifications of pipe heat extraction replacement part, have a strong impact on heat conducting effect, because the combustion technology of using falls behind, cigarette and dust concentration are very big simultaneously, in these granular dusts, there is a big part in " stove ", not have after-flame " coking carbon granules " again, this particle quality is hard, washes away the service life that the localized metallic pipe can reduce pipe throughout the year, has wasted a large amount of coal resources simultaneously again.Whole boiler plant is in operation, discharge lingemann blackness≤1 grade of flue gas during the operation of little load condition, yet the enterprise customer is moving at full capacity or under the overload state, but at this moment boiler is with regard to over-emitting black exhaust, flammable composition " fugitive constituent " is discharged in the atmosphere with the form of cigarette in a large number in the bituminous coal, the tar cigarette ash of heat-exchange surface also can be built up in a large number, the serious thermal efficiency that reduces, the ash content carbon of discharging is all more than 28-30%, the comprehensive utilization ratio of the energy is reduced greatly, promptly wasted the energy, polluted environment again, this is one " a worldwide hang-up " at boiler industry.

Summary of the invention

The object of the present invention is to provide a kind of bi-spiral flow smokeless steam boiler with chain grates, simple and reasonable, cheap, fired coal combustion is abundant, thermal efficiency height, and energy consumption is low, can solve coal-fired over-emitting black exhaust and dust stratification problem, the protection environment.

Bi-spiral flow smokeless steam boiler with chain grates of the present invention, comprise shell, water-cooling wall, the convection tube group, the coal-burning installation of drum and bottom, coal-burning installation comprises coaling gear, traveling-grate stoker, trimmer arch and stove rear arch, constitute front furnace between trimmer arch and the traveling-grate stoker, constitute rear hearth between stove rear arch and the traveling-grate stoker, the outlet of combustion heat gas is arranged between trimmer arch and the stove rear arch, its front furnace divides upper furnace and lower hearth, last lower hearth communicates, the front furnace cross section is two symmetrical R shape structures, the lower hearth of two R shape front furnaces communicates, the front furnace sidewall is fitted with the combustion-supporting air port of leading to upper furnace, the arc arch at combustion-supporting air port and upper furnace top is tangent, and the rear portion of front furnace is communicated with the outlet of combustion heat gas.

Lead to the combustion-supporting air channel of upper furnace at the front furnace sidewall along the pin setting of R shape, also be provided with the combustion-supporting air channel of leading to lower hearth along the pin of R shape, further promote burning at the front furnace sidewall.

Establish training wall upwards at the front end of stove rear arch, combustion heat gas is carried out water conservancy diversion, what preferably the water conservancy diversion coping is provided with tilts to combustion heat gas outlet side, further improves the water conservancy diversion effect.

So-called R shape also can be anti-R shape, can form clockwise eddy flow burning and counterclockwise swirl flow combustion respectively.

Cross section is the also just approximate pictograph of R shape structure to be described, can there be distortion to a certain degree to develop, as two pins of R shape can be that symmetry tilts, and can set up the combustion-supporting air channel of leading to lower hearth along two inclination pins, and the cross section of vortex furnace can be rounded or ellipse etc., burner hearth can be positioned at the middle part of body of heater, especially during symmetrical structure, generally be positioned at the middle part, at this moment, R shape structure will develop into approximate Ω shape, or the like.When structure was asymmetric, two tiltedly takeed on a weak point, and one long.

In the chimney arch (being bispin stream chimney arch) of front furnace, set up the supporting steel part, gain in strength, near the supporting steel part, establish the circulation cooling duct, be used for the cooling cooling.

In practice, according to the needs of all size the longitudinal length and the transverse width of body of heater are set, when the longitudinal length of body of heater was big, combustion-supporting air channel can distribute on longitudinal length and be provided with severally, guarantees fully to burn.

The present invention only improves the coal-burning installation in the steam boiler, and the structure that other structure can still be continued to use existing SZL series chain-arranged type steam boiler gets final product, and improves simply, is beneficial to by market and accepts.Coal-burning installation part and heat transfer structure part can be divided into two supporting body structures, make equipped respectively.

Coaling gear among the present invention comprises from manual coal that adds coal bunker and coaling machine automatic stoking device etc.

Operation principle:

Under the effect of the combustion air that enters from the air compartment fire grate, at high temperature burn in coal seam on the fire grate, produce a large amount of dense flue gases, coal tar steam wherein, coal gas (carbon monoxide), hydrocarbon gas, the particle of coal and subparticle or the like volatile combustible product can rise rapidly, air-flow is concentrated to two crown center quirks, compress and the flow velocity increase, this strand contains the high concentration flue gas of a large amount of flammable compositions and flame enters top with higher flow velocity swirl flow combustion zone, it is upper furnace, can claim " bispin stream combustion zone ", enter rotation status immediately, the eddy flow combustion air is through the combustion-supporting air channel of the right and left simultaneously, tangential direction with these two circles, spray with certain pressure and flow velocity, the two makes a concerted effort to form stronger turning moment, flammable flue gas and combustion-supporting oxygen (air) are mixed consumingly, cause burning fiercely, produce high temperature (1350-1450 ℃), this temperature has been strengthened the burning condition in this combustion zone more, according to " high-speed rotational principle ", these the two strands air-flows that rotate at a high speed all will produce consumingly " entrainmenting " effect to overhead all volatile materials of the whole front furnace that covers, none is slipped through the net, because the airflow route in the swirl flow combustion district is " a spiral stroke ", the track route and the residence time of fuel have greatly so extended, in this burning system, volatile fuel and combustible dust (flue gas): 1. essential temperature; 2. enough oxygen; 3. good stirring; 4. sufficient burning time.Essential elemental burns, " flawless " of Ti Xianing here, so flue gas will be by slap-up after-flame, what obtain is clean, tasteless, colourless, dustless high-temperature gas enters the high temperature turbulent area that the training wall place forms with certain flow rate, owing to lost " constraint " of combustion zone, air-flow begins to tear mutually to turn round, collision, pulverize, form many irregular disorderly air-flows, because the inertia of high speed swirling eddy, these air-flows still form " turbulence-like " in the rotation of establishing one's own system, and very high at this turbulent area degree of filling, here temperature reaches the highest simultaneously, and these high-temperature combustion gas are directly used in the heating of steam boiler.The two pass burning, burning capacity is big, satisfies the requirement of large-scale traveling-grate stoker formula steam boiler.

Bi-spiral flow smokeless steam boiler with chain grates of the present invention; fugitive constituent burn-off rate 100%; the gas of discharging is clean, colourless, tasteless, dustless; lingemann blackness is 0; the ash content carbon of discharging only has 3-5% (conventional boiler is more than 28%); compare with conventional boiler; 20-30% can economize on coal; simple and reasonable, cheap, thermal efficiency height; energy consumption is low; can solve coal-fired over-emitting black exhaust and heating surface area dust stratification problem, the protection environment, combination property can with advanced but expensive " CFBB " compare favourably.

Description of drawings

Fig. 1 is existing SZL type traveling-grate stoker formula steam boiler structural representation.

Fig. 2 is one embodiment of the invention structural representation in conjunction with operation logic.

Fig. 3 is the coal-burning installation structural representation among Fig. 2.

Fig. 4 is the front furnace cross-sectional structure schematic diagram among Fig. 3.

Fig. 5 is another kind of front furnace cross-sectional structure schematic diagram.

Among the figure: 1, flame-observing hole 2, front furnace 3, air compartment 4, manhole door 5, combustion heat gas outlet 6, traveling-grate stoker 7, stove rear arch 8, blast inlet 9, sealing block (also being grey iron block) 10, adjusting valve 11, back roller 12, slag notch 13, back manhole 14, backwater import 15, lower drum 16, convection tube group 17, water-cooling wall 18, upper drum 19, furnace wall 20, trimmer arch 21, coal bunker 22, coal flashboard 23, blanket roller 24, bispin stream chimney arch 25, upper furnace 26, burning gases outlet 27, training wall 28, high temperature turbulent area 29, the combustion-supporting air port 30 of secondary, coal seam 31,

grieshoch

32,33,35,36,38, the combustion-supporting air channel 34 of secondary, secondary air chamber 37, cloth wind box 39, water-cooled

steelframe

40,44, water-cooled steel plate 41, refractory material fixed claw 42, lower hearth 43, secondary air chamber F1, F2, combustion air B1, B2, air blast.

The specific embodiment

The invention will be further described below in conjunction with the embodiment accompanying drawing.

As Fig. 2, Fig. 3, shown in Figure 4, bi-spiral flow smokeless steam boiler with chain grates of the present invention, on existing SZL type traveling-grate stoker formula steam boiler basis shown in Figure 1, except that coal-burning installation, other continues to use original structure, comprise shell, water-cooling wall 17, convection tube group 16, last

lower drum

18,15 and the coal-burning installation of bottom, coal-burning installation is by coal bunker 21, the coaling gear that coal flashboard 22 is formed, traveling-grate stoker 6, trimmer arch and stove rear arch 7, constitute rear hearth between stove rear arch 7 and the traveling-grate stoker 6, constitute front furnace 2 between trimmer arch and the traveling-grate stoker 6,2 fens upper furnaces 25 of front furnace and lower hearth 42, last

lower hearth

25,42 communicate, the front furnace cross section is two symmetrical R shape structures, approximate Ω shape, and the lower hearth of two R shape front furnaces communicates, the front furnace sidewall is fitted with the combustion-supporting air port 29 of leading to upper furnace, combustion-supporting air port 29 is tangent with the arc arch at upper furnace 25 tops, makes front furnace form bispin stream burner hearth, and the rear portion of front furnace 2 is communicated with combustion heat gas outlet 26.The front end of stove rear arch 7 is provided with training wall 27 upwards, and the top of training wall 27 exports 26 lopsidedness to combustion heat gas, and the rear portion of front furnace 2 is communicated with combustion heat gas outlet 26, and the combustion-supporting

air channel

32,33,35,36,38 of air compartment 3 and secondary provides fire-retardant wind.The bispin stream chimney arch of burner is reinforced by water-cooled steelframe 39, water-cooled steel plate 40 and refractory material fixed claw 41, is provided with the recirculated water cooling passage in water-cooled steelframe 39 and the water-cooled steel plate 40, is used for cooling.

The course of work:

Under the effect of the combustion air that enters from air compartment 3, at high temperature burn in coal seam 30 on the traveling-grate stoker 6, produce a large amount of dense flue gases, coal tar steam wherein, coal gas (carbon monoxide), the particle of the coal that hydrocarbon gas evaporates and subparticle or the like volatile combustible product can rise rapidly, and the guiding that tiltedly takeed on by front furnace top two, air-flow is concentrated to two crown center quirks, compress and the flow velocity increase, because two oblique shoulders are not isometric, both sides corresponding downwards grate area also different, so the right flame flow is bigger than the flame flow density on the left side, flow velocity is also fast, the two deflection occurred when concentrating at fire channel place, last top, this strand contains the high concentration flue gas of a large amount of flammable compositions and flame enters top with higher flow velocity swirl flow combustion zone, it is upper furnace 25, also can be described as " bispin stream combustion zone ", enter rotation status immediately, the direction of rotation on both sides is just in time opposite, the eddy flow combustion air is through the combustion-supporting air port 29 or the air channel 32 of the right and left simultaneously, 33,35,36,38, tangential direction with these two circles, spray with certain pressure and flow velocity, the two makes a concerted effort to form stronger turning moment, flammable flue gas and combustion-supporting oxygen (air) are mixed consumingly, cause burning fiercely, produce high temperature, reach 1350-1450 ℃, strengthened the burning condition in this combustion zone more, according to " high-speed rotational principle ", these the two strands air-flows that rotate at a high speed all will produce consumingly " entrainmenting " effect to overhead all volatile materials of the whole front furnace that covers, none is slipped through the net, because the airflow route in the swirl flow combustion district is " a spiral stroke ", the track route and the residence time of fuel have greatly extended, in this burning system, volatile fuel and combustible dust (flue gas) have: 1. essential temperature; 2. enough oxygen; 3. good stirring; 4. sufficient burning time, essential elemental burns, " flawless " of Ti Xianing here, so flue gas will be by slap-up after-flame, what obtain is clean, tasteless, colourless, dustless high-temperature gas enters the high temperature turbulent area that training wall 34 places form with certain flow rate, owing to lost " constraint " of combustion zone, air-flow begins to tear mutually to turn round, collision, pulverize, form many irregular disorderly air-flows, because the inertia of high speed swirling eddy, these air-flows still form " turbulence-like " in the rotation of establishing one's own system, and it is very high at this turbulent area degree of filling, here temperature reaches the highest simultaneously, and these high-temperature combustion gas are directly used in the heating of steam boiler.

The thickness in coal seam can be determined according to the height that the boiler heat load adjustment is positioned at the coal flashboard of trimmer arch front, this stage from the coal flashboard to manhole door, it is the zone that " fugitive constituent " of bituminous coal separated out in a large number, " yet bispin stream combustion zone " is in the top of going up in this zone just, all flue gases all will be involved in this high temperature flue that rotates at a high speed, by thorough after-flame, clean flame flow enters the high temperature turbulent area that the training wall place forms with certain flow rate.

The bituminous coal of front is quilt " destructive distillation " while walking, fugitive constituent volatilizees basically and burns totally, after the process manhole door is sentenced, become " coke ", " burning-point " of this coke is very high, there is not sufficiently high temperature to burn endless, " high temperature turbulent area " yet here just just, so " burnt nuclear " in the lime-ash that in conventional boiler, is difficult to burn, in this zone also by thorough after-flame, the lime-ash of after-flame is " noncombustibles " all, and the motion backward along with fire grate falls into ash hole and discharges out of the furnace.

In addition, in order to make the coke after-flame, " coke forms the district " corresponding air compartment has certain ventilation (can regulate by corresponding air-valve), again because this regional gas permeability is fine, there be a small amount of " overheated remaining oxygen " to pass coke layer always and add to this " high temperature turbulent area ", this just more makes the condition of burning reach best, suppose to leak and serve flue gas from the front, also can be by this " high-intensity zoneofoxidation " slap-up oxidizing away, certain superfluous oxygen is too many, because temperature is too high, be easy to generate harmful nitrogen oxide (NOx) again.Can reasonably regulate this regional air capacity under the prerequisite that does not have cigarette fully, suitably be in " reasonably anaerobic condition ", because of the chemical property of nitrogen (N) active not as the chemical property of the carbon (C) under the red-hot state, so following reduction reaction occurs:

NOx+HC→CO ₂+H ₂O+N

NOx+CO→CO ₂+N

NOx+C→CO ₂+N

Nitrogen oxide is seized oxygen atom by carbon and hydrogen as a result, is reduced into nitrogen again.

Therefore, " high temperature turbulent area " is equivalent to the tight pernicious gas of one deck " screen pack ", and all none is processed into non-toxic gas with slipping through the net and emits through this zone the time for three kinds of toxic gases.

In the chemical examination of coal, the material of incombustibility is called " ash ", difference according to the constitutional chemistry composition, the temperature of pairing " ash fusion point " is also different, but the overwhelming majority can melt to burn about 1350 ℃ to form slag, fraction in burning in these ash rises up slowly with air-flow, contained flammable composition is suspended the afterburnt, not flammable composition will form tiny " slag dirt ", because very light weight, shape is disorderly and unsystematic, aerodynamic effect is preferably arranged, taken away by air-flow easily or with the form of dust stratification be deposited on the boiler tube and the boiler random in or float in the atmosphere through chimney and to go, this is a matter of course feelings in traditional combustion apparatus, is not so just in the present invention.

In combustion mode of the present invention, combustible dust and incombustibility dust are under suspended state and high temperature, rotary collision intensely, because temperature is very high, generally be between 1350 ℃-1450 ℃, this temperature almost is all ash " ash fusion points ", because fine dust is fused into small " bead " easily fast, add again at swirl flow combustion section motion collision intensely, wherein some also can be agglomerated into bigger " bead " shape, no matter be big and tiny all having become " sphere ", the aerodynamic quality of this geometry is bad, be difficult to floating with air-flow, go so can settle out to stick together to be discharged to outside the stove at " high temperature turbulent area " with following big lime-ash, has only few part along with the high velocity air that upwards sprays enters into very big boiler cup the inside, space, here the speed of air-flow is slack-off rapidly, add the cooling effect of water-cooling wall again, temperature also reduces rapidly, these " microballoons " have lost high velocity air " supporting effect ", settle out immediately, be deposited on the bottom of " cup ", pass through ash removing opening, periodic cleaning is come out, can not be bonded on the heat-exchange surface of boiler, so perfect combination of the present invention makes " pot " and " stove " all can reach best running status, realizes high efficiency truly, low energy consumption.

Shown in Figure 5 is another kind of front furnace cross-sectional structure schematic diagram, and the front furnace cross section is the oblique shoulder of two symmetrical R shape structures to be adjusted to some extent, makes the direction of rotation of air-flow opposite, and principle is with shown in Figure 4 identical.And secondary air chamber 43 and water-cooled steel plate 44 have been increased.

Cloth wind box can be passed through in the combustion-supporting air channel of among the present invention each, realizes that as required cloth wind distributes, and provides cloth pneumatic power by same power source, simplifies auxiliary equipment.

Air feed system can be equipped with the automation frequency-changing control system, realizes automation mechanized operation.Mode as the available frequency control of adjusting of wind supply quantity solves, that is changes the method control wind supply quantity of the rotating speed of blower fan by the frequency that changes fan power.Utilize flue gas sensor (the industrial electronic retail department all has commercially available), as zirconium dioxide flue gas sensor, it presents " gas sensitive effect " to carbon monoxide, as long as it is exactly anoxic that flue gas is arranged, as long as anoxic just certainly leads to carbon monoxide, so the content of detection CO gas how much, also just directly reflected " air distribution coefficient " and the combustion conditions of combustion apparatus inside.The content of CO gas is become on the voltage signal input terminal that voltage signal is input to frequency converter, can utilize the voltage signal controlled frequency to change, the frequency conversion out-put supply is exactly the power supply of air blast, like this, rational air distribution coefficient can be arranged, fundamentally control the excessive generation of nitrogen oxide.

Claims

1, a kind of bi-spiral flow smokeless steam boiler with chain grates, comprise shell, water-cooling wall, the convection tube group, the coal-burning installation of drum and bottom, coal-burning installation comprises coaling gear, traveling-grate stoker, trimmer arch and stove rear arch, constitute front furnace between trimmer arch and the traveling-grate stoker, constitute rear hearth between stove rear arch and the traveling-grate stoker, the outlet of combustion heat gas is arranged between trimmer arch and the stove rear arch, it is characterized in that front furnace divides upper furnace and lower hearth, last lower hearth communicates, the front furnace cross section is two symmetrical R shape structures, the lower hearth of two R shape front furnaces communicates, the front furnace sidewall is fitted with the combustion-supporting air port of leading to upper furnace, the arc arch at combustion-supporting air port and upper furnace top is tangent, and the rear portion of front furnace is communicated with the outlet of combustion heat gas.

2, bi-spiral flow smokeless steam boiler with chain grates according to claim 1 is characterized in that the front furnace sidewall leads to the combustion-supporting air channel of upper furnace along the pin setting of R shape.

3, bi-spiral flow smokeless steam boiler with chain grates according to claim 2 is characterized in that the front furnace sidewall is provided with the combustion-supporting air channel of leading to lower hearth along the pin of R shape.

4,, it is characterized in that the front end of stove rear arch is provided with training wall upwards according to claim 1,2 or 3 described bi-spiral flow smokeless steam boiler with chain grates.

5, bi-spiral flow smokeless steam boiler with chain grates according to claim 4 is characterized in that the water conservancy diversion coping tilts to combustion heat gas outlet side.

6, bi-spiral flow smokeless steam boiler with chain grates according to claim 5 is characterized in that having additional the supporting steel part in the chimney arch of front furnace, is provided with the circulation cooling duct near the supporting steel part.