The specific embodiment
To combine the accompanying drawing in the embodiment of the invention below, the technical scheme in the embodiment of the invention is carried out clear, intactly description, obviously, described embodiment only is the present invention's part embodiment, rather than whole embodiment.Based on the embodiment among the present invention, those of ordinary skills are not making the every other embodiment that is obtained under the creative work prerequisite, all belong to the scope of the present invention's protection.
Embodiment one
As shown in Figure 2; Structural representation for moisture and latent heat of vaporization recovery system in the brown coal flue gas provided by the invention; Moisture and latent heat of vaporization recovery system comprise in this brown coal flue gas: boiler 203, heater 202, steam turbine 201, air preheater 204, deduster 205 and chimney 206; Be connected through water pipe between said heater and boiler and the steam turbine; Connect through steam pipeline between said boiler and the steam turbine, said boiler, air preheater, deduster and chimney are connected through flue, and said system also comprises: the latent heat recover;
Said latent heat recover is connected in through flue between the inlet of outlet and said chimney of said deduster, is used to absorb the heat that said deduster is discharged flue gas;
Said latent heat recover also is connected between the inlet of water side outlet and said heater of said steam turbine through water pipe, is used for the condensate of discharging through the said steam turbine of the heat that absorbs.
In the present embodiment,, realized recovery, reached the effect of energy-saving and emission-reduction the heat in the flue gas through increasing the latent heat recover in traditional brown coal combustion system.
Embodiment two
As shown in Figure 3; Structural representation for moisture and latent heat of vaporization recovery system in the brown coal flue gas provided by the invention; Wherein, condenser 301 is connected in the low-temperature receiver end of steam turbine low pressure (LP) cylinder LP, is used for the steam of steam turbine low pressure (LP) cylinder outlet is condensed into water; Vapour volume die-offs in this process, has kept the pressure differential of high steam;
Coagulate pump 302 and be connected with condenser 301, the water pressure that condenser 301 condensations produce is very low, coagulates pump 302 and is used to make it to boost, and makes water can overcome the resistance of latent heat recover 303 and connection pipeline, flows in the oxygen-eliminating device 304.
Latent heat recover 303 is connected in through flue between the inlet of outlet and hair-dryer 315 of deduster 314, is used to absorb the heat that said deduster 314 is discharged flue gases; Said latent heat recover 303 also is connected between the inlet of said outlet of coagulating pump 302 and oxygen-eliminating device 304 through water pipe, is used for coagulating the condensate that pump 302 is discharged through the heat that absorbs is said.
Oxygen-eliminating device 304, feed pump 305, high-pressure heater 306~308 have been formed the heating system step by step in the native system; At this step by step in the heating system; If than certain one-level heater more high pressure heater draw gas condense into water after; The pressure of its this level of pressure ratio is also high, in the hydrophobic heater that is pressed onto lower pressure that at this moment pressure differential is condensed in will the heater with high pressure, is called gravity flow step by step.
Wherein, Oxygen-eliminating device 304 is connected with steam turbine intermediate pressure cylinder IP, latent heat recover 303 and feed pump 305; Be used for through the drawing gas of steam turbine intermediate pressure cylinder IP, the feedwater that latent heat recover 303 is sent here, and high-pressure heater 306 is heated to 150 ~ 180 ℃ from the water that flow to oxygen-eliminating device 304.Oxygen-eliminating device 304 tops are designed with an osculum simultaneously, are used for making the minor amounts of oxygen that is dissolved in water together to be discharged in the atmosphere with steam and go.
Feed pump 305 is used for the oxygen-eliminating device condensate is boosted to very high pressure; Overcome the resistance of the steam-water pipeline that arrives boiler export here; And for the high vapour pressure of steam turbine inlet provides a basis, promptly heating makes water pressure very high on this basis, just can reach the high vapour pressure of steam turbine inlet.
High-pressure heater 306~308 is connected with steam turbine high pressure cylinder HP respectively, is heated to higher temperature through drawing gas of steam turbine high pressure cylinder HP with the feedwater that feed pump 305 is got.
In boiler; The hot water that high-pressure heater 308 is discharged is through economizer 309; Evaporimeter 310 and superheater 311 become steam, are delivered to steam turbine high pressure cylinder HP acting, and the steam discharge of high pressure cylinder HP is delivered to intermediate pressure cylinder IP acting after heating once more through the reheater 312 in the boiler.
Simultaneously, the flue gas that the burning brown coal produce by behind the latent heat recover 303 recovery heats, blows to smoke stack emission through induced-draught fan 315 after air preheater 313, deduster 314 are handled again.
Wherein, As shown in Figure 4; Said latent heat recover 303 further comprises: panel-pipe of heating surface 401; Be arranged in the flue of said latent heat recover and be connected between the inlet of water side outlet and heater of the steam turbine in the brown coal combustion system, be used for that said deduster is discharged flue gas and cool off so that the steam of flue gas is condensed into water through water pipe, and the condensate of discharging through the said steam turbine of heat that cooled flue gas absorbs; Heating surface water collector 402 is arranged at said panel-pipe of heating surface below, is used to collect the water that said flue gas cooling back produces;
Also can comprise water pump 403, be connected in said heating surface water collector and water pipe, be used for described water is transported to water pipe.
In the present embodiment,, realized recovery, reached the effect of energy-saving and emission-reduction the heat in the flue gas through in traditional boiler using brown coal, increasing the latent heat recover.
Embodiment three
As shown in Figure 5; The sectional structure chart of a kind of latent heat recover that provides for the embodiment of the invention; Wherein, panel-pipe of heating surface 502 connects on steam turbine condensate line or the heat exchangers for district heating pipeline, and is arranged in the flue 501 of said latent heat recover; Be used for that said deduster is discharged flue gas and cool off so that the steam of flue gas is condensed into water, thus absorbed the heat in the flue gas with in the heating panel-pipe of heating surface 502 from the water of steam turbine condensate line or heat exchangers for district heating pipeline; In a preferred version, panel-pipe of heating surface can be designed to the heat pipe form, also can be designed to conventional coiled pipe.Simultaneously, for anticorrosion, the base material of panel-pipe of heating surface is an ordinary carbon steel, and outer wall need plate enamel, and the transverse pitch of pipe is greater than 50mm simultaneously.
Wherein, flue 501 contains sour workspace owing to being operated in, so need inside to add anticorrosion process.
Heating surface water collector 503 is a sagging awl bucket, and the condensation flow on panel-pipe of heating surface 502 surfaces are in this water collector.
Agitator 504 is arranged in the said water collector 503, be used for stirring said water collector water so that the dust in the water do not precipitate; Because when heating surface catchments, also collected the dust in a small amount of flue gas simultaneously.
Wherein, if being used for the latent heat of the flue gas of fuel such as natural gas, reclaims by above-mentioned latent heat recover, because dust seldom, so can cancel agitating device.
Water pump 505 is connected in the delivery port of said heating surface water collector 503 through water pipe, is used for getting to the water of water collector the direction of first control gate 506 and second control gate 507 in the water pipe.
First control gate 506 is opened when the water level in the water collector that is used for measuring according to liquid meter 509 is high, so that water pump 505 is got to a sedimentation basin with water, the water of post precipitation can utilize after treatment.
Second control gate 507 is used to control water collector 503 to the cooling tube purging device 508 needed water yields.
Heating surface tube purging device 508 is by forming with the scavenging conduit of some small-bores on the long pipeline, and under the effect of elevated pressures, current can wash the outer surface of described panel-pipe of heating surface 502, prevent grey stick on top.
In the above-described embodiments, after the higher hot cigarette of water content gets into heater, receive the surface condensation Cheng Shui of cooling, 503 li of the heating surface water collectors below flowing at panel-pipe of heating surface 502.Stirring the maintenance dust through agitator 504 in the heating surface water collector 503 does not precipitate; And be driven in the heating surface tube purging device 508 by water pump 505; Heating surface tube purging device 508 can form thin current at a high speed; The heating surface surface is cleaned, and accelerated the cooling of flue gas, be brought into the heat in the part of smoke in the water.After the liquid level in the water collector was higher than certain certain value, first control gate 506 was opened, and more recycle-waters was sent to sedimentation basin and recycled.
Because the amount of the latent heat of vaporization is very big; The latent heat of vaporization that the water vapour of 1kg evaporates under normal pressure is about 2500kJ/kg; Like this, if moisture is high in the flue gas, through said apparatus can reclaim moisture in a large amount of low-temperature zone flue gases with the latent heat of vaporization and moisture.With typical China triumph coalfield brown coal is example, if can all reclaim heat and moisture content, and the recyclable caloric value that is equivalent to coal itself 10% of then every t coal; 0.34t water, the exhaust gas volumn volume reduces 17%, one 600MW unit oepration at full load 1 hour simultaneously; With consuming such 400t coal, the heat of recovery just is equivalent to the 40t coal, 130t water; Will be to the energy-saving and emission-reduction of China, particularly there is huge meaning the water-deficient area, the Northwest, and this coal Value Data is as shown in table 1:
Project |
Symbol |
Unit |
Check coal |
Total moisture |
Mar |
% |
34.1 |
Air-dried moisture |
Mad |
% |
19.56 |
The As-received ash content |
Aar |
% |
15.58 |
The dry ash free basis fugitive constituent |
Vdaf |
% |
44.37 |
As-received carbon |
Car |
% |
34.83 |
As-received hydrogen |
Har |
% |
2.89 |
As-received oxygen |
Oar |
% |
10.79 |
As-received nitrogen |
Nar |
% |
0.71 |
The full sulphur of As-received |
St.ar |
% |
1.1 |
The As-received low heat valve |
Qnet.ar |
kJ/kg |
12900 |
The As-received high calorific power |
Qnet.gw |
kJ/kg |
14280 |
The latent heat of vaporization that 1kg walks in the ribbing |
Qqr |
kJ/kg |
1380 |
Reclaim heat and be equivalent to the raw coal heat |
Qhs |
% |
11 |
Theoretical dry air amount |
V0 |
Nm
3/kg
|
3.5264 |
Theoretical dry flue gas amount |
V0y |
Nm
3/kg
|
3.4457 |
The smoke evacuation excess air coefficient |
αpy |
_ |
1.4 |
The dry flue gas amount |
Vgy |
Nm3/kg |
4.8562 |
Water vapour volume in the flue gas |
VH2O |
Nm3/kg |
0.8245 |
Flue gas reduces ratio |
VH2O/Vgy |
% |
17 |
The callable moisture weight of 1kg coal |
GH2O |
kg/kg |
0.34 |
The typical high-moisture brown coal of table 1 parameter
Embodiment four
At present general unit thermodynamic system is as shown in Figure 6, is made up of 8 grades of heaters, heats condenser with drawing gas and comes water, makes the latent heat of vaporization of this part steam can't help condensing with minimizing and takes away, but get back to boiler, thereby play energy-conservation effect, wherein h
1-h
8Be the enthalpy of bleeding, h
W0-h
W8Be feedwater enthalpy, h
S1-h
S4, h
S6-h
S8Be hydrophobic enthalpy.
With certain 600MW supercritical unit is example, and under the rated load, main stripping temperature is 24Pa; Main stripping temperature is 566 ℃, and main steam flow amount is 1755t/h, 41 ℃ of condenser temperatures; The saturated vapor enthalpy is 2575kJ/kg under this temperature, and the saturation water enthalpy is 171kJ/kg, and the parameter that each section heater draws gas is as shown in table 2:
Table 2
In order to save the steam that heat regenerative system is used for heated feed water, make it be used for acting, replace these to draw gas with the fume afterheat behind the deduster, and reclaim the moisture in the high-moisture flue gas.With the heating system calculation of parameter that above-mentioned 600MW steam turbine is a sample design, can replace 1 ~ 4 section to draw gas, the acting ability that every 1kg increases is the flow weighted averages of acting ability of drawing gas that are heated at different levels, that is:
1 ~ 4 section acting ability=∑ amount of drawing gas of drawing gas * (enthalpy-exhaust enthalpy draws gas)
This patent design can get every resulting income of 1kg Steam Recovery heat (merit) and is 37kJ (shown in the table 3) thus.With respect to unit shown in Figure 6; The unit that the embodiment of the invention provides is imported under the constant situation of heat (also importing steam turbine 1755t/h steam) at boiler; Per hour multiple electric weight is: 37*1755*1000=65MJ, and being equivalent to generator power has increased 65/3.6=18MW, and 3%.
Table 3
Match and to find with the brown coal of high-moisture shown in the table 1: if the latent heat of vaporization of brown coal all reclaims; It is equivalent to low heat valve increases by 11%; And said system can only reclaim 3%; Thereby high-moisture brown coal unit also is not enough to all reclaim these heats with such Steam Turbine, must be used again.Because the restriction of temperature, reclaim these heats with steam turbine and be difficult to so that allowance to be arranged again, thereby want to utilize these heats, must be arranged on the outer part of therrmodynamic system to heater.
As shown in Figure 7; Structural representation for moisture and latent heat of vaporization recovery system in the brown coal flue gas provided by the invention; Moisture and latent heat of vaporization recovery system comprise in these brown coal: condenser 301, coagulate pump 302, latent heat recover 303, oxygen-eliminating device 304, feed pump 305, high-pressure heater 306~308, economizer 309, evaporimeter 310, superheater 311, reheater 312, air preheater 313, deduster 314, hair-dryer 315 and chimney.Comprise in addition:
Heat supply network latent heat recover 316; Through flue be connected in said latent heat recover and the inlet of outlet and said chimney between; Be connected in heat network system through water pipe, be used to absorb the heat that said latent heat recover is discharged flue gas, and the heat that absorbs is delivered to said heat network system through water pipe.
The internal structure of said heat supply network latent heat recover 316 is identical with latent heat recover 303, and its delivery port and water inlet are connected in heat network system, through increasing heat supply network latent heat recover 316; Supply the heating backwater; Because the temperature of backwater is very low, its utilization for heat is a magnanimity, will require also not high to temperature; Also it doesn't matter than exhaust gas temperature height even leaving water temperature requires; Can further heat the water of this heater outlet (the outlet water temperature does not satisfy the heat supply requirement), or directly pass out to heat supply network (the outlet water temperature satisfies the heat supply requirement), reach and reclaim all latent heats of vaporization.
Embodiment five
As shown in Figure 8, reclaim the method for the latent heat of vaporization and moisture in a kind of brown coal flue gas that provides for the embodiment of the invention in moisture and the latent heat of vaporization recovery system, this method comprises:
Step 801 absorbs the heat of the flue gas that deduster is discharged in the moisture and latent heat of vaporization recovery system in the said brown coal flue gas;
Step 802 is through steam turbine condensate in moisture and the latent heat of vaporization recovery system in the said brown coal of heat that absorb.
The heat of the flue gas that in an embodiment of the present invention, deduster is discharged in moisture and the latent heat of vaporization recovery system in the said brown coal flue gas of said absorption comprises:
Said deduster is discharged flue gas to be cooled off so that the steam in the flue gas is condensed into water.
The detailed process of above-mentioned steps is similar with aforementioned means embodiment, repeats no more at this, through reclaiming the moisture and the latent heat of vaporization in the brown coal flue gas, has reached the effect of energy-saving and emission-reduction.
It will be appreciated by those skilled in the art that accompanying drawing is the sketch map of a preferred embodiment, unit in the accompanying drawing or flow process might not be that embodiment of the present invention is necessary.The invention described above embodiment sequence number is not represented the quality of embodiment just to description.
Above embodiment is the preferred embodiments of the disclosure, and the common variation that the those skilled in the art carries out in the technical scheme of the embodiment of the invention, change or replacement all should be included within protection scope of the present invention.