CN105021357A - Air preheater air leakage rate determination method and device - Google Patents

Abstract

The invention discloses an air preheater air leakage rate determination method and a device. The air preheater is a tri-section air preheater. The method comprises steps: an average oxygen content at the inlet of the air preheater is acquired; according to the average oxygen content at the inlet of the air preheater, an excess air coefficient at the outlet of the air preheater is determined; according to the excess air coefficient at the outlet of the air preheater, an excess air coefficient at the inlet of the air preheater is determined; according to smoke temperature at the inlet of the air preheater, primary air temperature at the outlet of the air preheater, secondary air temperature at the outlet of the air preheater, primary air temperature at the inlet of the air preheater and secondary air temperature at the inlet of the air preheater, smoke temperature at the non-air leakage outlet of the air preheater is determined; according to the primary air temperature and the secondary air temperature, the air leakage temperature of the air preheater is determined; according to the smoke temperature at the non-air leakage outlet of the air preheater, the actual smoke exhaust temperature of a boiler and the air leakage temperature of the air preheater, the air leakage coefficient increment at the outlet of the air preheater is determined; and according to the air leakage coefficient increment at the outlet of the air preheater and the excess air coefficient at the inlet of the air preheater, the air leakage rate of the air preheater is determined. Thus, the air leakage rate of the air preheater can be accurately acquired.

Description

Air preheater air leakage rate defining method and device

Technical field

The present invention relates to boiler technology field, particularly relate to air preheater air leakage rate defining method and device.

Background technology

Air preheater (air pre-heater) is that the flue gas in boiler back end ductwork will enter the heating surface of the preheating of air before boiler to uniform temperature by inner heat radiator, for improving the heat exchange performance of boiler, reduce energy ezpenditure, generally referred to as air preheater.

Air preheater is the main auxiliary equipment of coal-fired station, and air preheater air leakage rate can be determined by the method for test.When determining air preheater air leakage rate, fume side outlet, entrance arrange very close measuring point by gridding method, press flow weighted average calculation discrepancy oxygen amount, calculate with formula (1) after measuring oxygen amount.

${\mathrm{\α}}_L=90\frac{O_{2Lv}-O_{2En}}{21-O_{2En}}=90\frac{{\mathrm{\α}}_2-{\mathrm{\α}}_1}{{\mathrm{\α}}_1}---\left(1\right)$

Wherein, α _lfor air preheater air leakage rate; O _2Lvfor air preheater entrance oxygen amount, O _2Enfor air preheater outlet oxygen amount, α ₂for air preheater outlet excess air coefficient; α ₁for air preheater entrance excess air coefficient.

Gridding method is the method for gathering flue gas sample in station boiler flue, use during the method and arrange multiple measuring point by equal-area method on the xsect of rectangle or circular flue, gather flue gas sample at each point position respectively, finally again weighted mean value is got to the measurement result of all measuring points.For rectangular flue, normally offer row's gaging hole in a first-class spacing in limit of flue xsect, each gaging hole different depth place arranges measuring point equally spacedly.According to the regulation of industry standard, the spacing of net point is generally about 0.6m ~ 1m.

When using grid survey oxygen amount, the smoke components distribution of air preheater entry position is relatively uniform, but in exit position, because the pressure differential of exhaust gases passes both sides has difference greatly, thus inleakage difference is very large, and cause exiting flue gas composition difference very large, the oxygen amount accuracy of measurement is lower.

Prior art is also considered to utilize Oxygen Measuring Instrument on-line measurement air preheater entrance oxygen amount O _2Lvwith outlet oxygen amount O _2En, the air leak rate of air curtain of air preheater is then directly calculated according to formula (1).When on-line measurement uses zirconia to measure oxygen amount, the limited length of zirconia head, generally can not more than 2m, and scene, in order to increase the measurement of air preheater air leakage rate, generally exports installation three zirconia measuring points at air preheater.But due to the unevenness of this place's oxygen amount, if there is the high oxygen amount air-flow of a local at measuring point place, or do not detect the high tolerance air-flow of this local, all can cause huge deviation.

Summary of the invention

The embodiment of the present invention provides a kind of air preheater air leakage rate defining method, and in order to obtain air preheater air leakage rate more accurately, described air preheater is three points of storehouse air preheaters, and described method comprises:

Obtain the average oxygen amount of air preheater entrance;

According to the average oxygen amount of air preheater entrance, determine air preheater outlet excess air coefficient;

According to air preheater outlet excess air coefficient, determine air preheater entrance excess air coefficient;

According to air preheater inlet flue gas temperature, air preheater outlet First air temperature, air preheater outlet Secondary Air temperature, air preheater entrance First air temperature and air preheater entrance Secondary Air temperature, determine that air preheater is without outlet cigarette temperature of leaking out;

According to First air temperature and Secondary Air temperature, determine that air preheater flue gas leaks out temperature;

To leak out temperature without leak out outlet cigarette temperature, boiler actual exhaust gas temperature and air preheater flue gas according to air preheater, determine that air preheater exports air leakage coefficient recruitment;

According to air preheater outlet air leakage coefficient recruitment and air preheater entrance excess air coefficient, determine air preheater air leakage rate.

The embodiment of the present invention also provides a kind of air preheater air leakage rate determining device, and in order to obtain air preheater air leakage rate more accurately, described air preheater is three points of storehouse air preheaters, and described device comprises:

The average oxygen amount of entrance obtains module, for obtaining the average oxygen amount of air preheater entrance;

Outlet excess air coefficient determination module, for according to the average oxygen amount of air preheater entrance, determines air preheater outlet excess air coefficient;

Entrance excess air coefficient determination module, for according to air preheater outlet excess air coefficient, determines air preheater entrance excess air coefficient;

Without the outlet cigarette temperature determination module that leaks out, for according to air preheater inlet flue gas temperature, air preheater outlet First air temperature, air preheater outlet Secondary Air temperature, air preheater entrance First air temperature and air preheater entrance Secondary Air temperature, determine that air preheater is without outlet cigarette temperature of leaking out;

Flue gas leaks out temperature determination module, for according to First air temperature and Secondary Air temperature, determines that air preheater flue gas leaks out temperature;

Outlet air leakage coefficient recruitment determination module, for leaking out temperature without leak out outlet cigarette temperature, boiler actual exhaust gas temperature and air preheater flue gas according to air preheater, determines that air preheater exports air leakage coefficient recruitment;

Air leak rate of air curtain determination module, for according to air preheater outlet air leakage coefficient recruitment and air preheater entrance excess air coefficient, determines air preheater air leakage rate.

In the embodiment of the present invention, air preheater air leakage rate is determined according to air preheater outlet air leakage coefficient recruitment and air preheater entrance excess air coefficient, wherein air preheater outlet air leakage coefficient recruitment and air preheater entrance excess air coefficient export oxygen amount without using air preheater in deterministic process, therefore the embodiment of the present invention measures air preheater outlet oxygen amount without the need to adopting gridding method or Oxygen Measuring Instrument, avoid the layout of high level error and the air preheater outlet oxygen amount measuring point measured and bring, air preheater air leakage rate more accurately can be obtained.

Accompanying drawing explanation

In order to be illustrated more clearly in the embodiment of the present invention or technical scheme of the prior art, be briefly described to the accompanying drawing used required in embodiment or description of the prior art below, apparently, accompanying drawing in the following describes is only some embodiments of the present invention, for those of ordinary skill in the art, under the prerequisite not paying creative work, other accompanying drawing can also be obtained according to these accompanying drawings.In the accompanying drawings:

Fig. 1 is the schematic diagram of air preheater air leak rate of air curtain defining method in the embodiment of the present invention;

Fig. 2 is the schematic diagram of three points of storehouse air preheaters in the embodiment of the present invention;

Fig. 3 is the schematic diagram of air preheater air leak rate of air curtain determining device in the embodiment of the present invention.

Embodiment

For making the object of the embodiment of the present invention, technical scheme and advantage clearly understand, below in conjunction with accompanying drawing, the embodiment of the present invention is described in further details.At this, schematic description and description of the present invention is for explaining the present invention, but not as a limitation of the invention.

Fig. 1 is the schematic diagram of air preheater air leak rate of air curtain defining method in the embodiment of the present invention.As shown in Figure 1, in the embodiment of the present invention, air preheater air leak rate of air curtain defining method can comprise:

Step 101, the average oxygen amount of acquisition air preheater entrance;

Step 102, according to the average oxygen amount of air preheater entrance, determine air preheater outlet excess air coefficient;

Step 103, according to air preheater outlet excess air coefficient, determine air preheater entrance excess air coefficient;

Step 104, according to air preheater inlet flue gas temperature, air preheater outlet First air temperature, air preheater outlet Secondary Air temperature, air preheater entrance First air temperature and air preheater entrance Secondary Air temperature, determine that air preheater is without outlet cigarette temperature of leaking out;

Step 105, according to First air temperature and Secondary Air temperature, determine that air preheater flue gas leaks out temperature;

Step 106, to leak out temperature without leak out outlet cigarette temperature, boiler actual exhaust gas temperature and air preheater flue gas according to air preheater, determine that air preheater exports air leakage coefficient recruitment;

Step 107, according to air preheater outlet air leakage coefficient recruitment and air preheater entrance excess air coefficient, determine air preheater air leakage rate; Air preheater wherein in the embodiment of the present invention is three points of storehouse air preheaters.

Flow process can be learnt as shown in Figure 1, in the embodiment of the present invention, air preheater air leakage rate is determined according to air preheater outlet air leakage coefficient recruitment and air preheater entrance excess air coefficient, wherein air preheater outlet air leakage coefficient recruitment and air preheater entrance excess air coefficient export oxygen amount without using air preheater in deterministic process, therefore the embodiment of the present invention measures air preheater outlet oxygen amount without the need to adopting gridding method or Oxygen Measuring Instrument, avoid the layout of high level error and the air preheater outlet oxygen amount measuring point measured and bring, air preheater air leakage rate more accurately can be obtained.

The embodiment of the present invention mainly according to air preheater air leakage rate and primary and secondary air running temperature, pressure and thermal equilibrium relation of leaking out, determines air preheater air leakage rate.In embodiment, first obtain the average oxygen amount of air preheater entrance.Grid survey such as can be utilized to obtain the average oxygen amount of air preheater entrance; Or, Oxygen Measuring Instrument on-line measurement can be utilized to obtain the average oxygen amount of air preheater entrance.Because the smoke components distribution in air preheater entry position is relatively uniform, not only can utilize grid survey oxygen amount but also Oxygen Measuring Instrument on-line measurement oxygen amount can be utilized, two kinds of method measurement results are all very accurate, but utilize gridding method to need instrument on survey crew band to remove in-site measurement, if utilize Oxygen Measuring Instrument to realize the on-line measurement of entrance oxygen amount, air leak rate of air curtain can directly calculate again, calculate result directly to show on power plant's computer, just can realize On-line sampling system air leak rate of air curtain, tester need not go to scene, so just saves man power and material.

In embodiment, after the average oxygen amount of acquisition air preheater entrance, according to the average oxygen amount of air preheater entrance, air preheater outlet excess air coefficient can be determined, then according to air preheater outlet excess air coefficient, determine air preheater entrance excess air coefficient.Wherein export excess air coefficient according to air preheater entrance average oxygen amount determination air preheater and can have multiple according to the method for air preheater outlet excess air coefficient determination air preheater entrance excess air coefficient, such as:

By following formula according to the average oxygen amount of air preheater entrance, determine air preheater outlet excess air coefficient:

${\mathrm{\α}}_2=\frac{21}{21-O};$

Wherein, α ₂for air preheater outlet excess air coefficient, O is the average oxygen amount of air preheater entrance;

Export excess air coefficient by following formula according to air preheater, determine air preheater entrance excess air coefficient:

α ₁＝α ₂-∑Δα′；

Wherein, α ₁for air preheater entrance excess air coefficient, Δ α ' is boiler other place under rated load except air preheater, the such as air leak rate of air curtain in other place such as pipeline.

During concrete enforcement, also according to air preheater inlet flue gas temperature, air preheater outlet First air temperature, air preheater outlet Secondary Air temperature, air preheater entrance First air temperature and air preheater entrance Secondary Air temperature, determine that air preheater is without outlet cigarette temperature of leaking out.Concrete, determine air preheater without leak out outlet cigarette temperature time, can also carry out in conjunction with parameters such as the specific heat of the specific heat of the mass ratio of air in air preheater and flue gas, air, flue gas, primary air ratio and secondary air ratios.Such as, by following formula according to air preheater inlet flue gas temperature, air preheater outlet First air temperature, air preheater outlet Secondary Air temperature, air preheater entrance First air temperature and air preheater entrance Secondary Air temperature, can determine that air preheater is without outlet cigarette temperature of leaking out:

${\mathrm{\θ}}_{NL}={\mathrm{\θ}}_1-\mathrm{\κ}\·\frac{c_{pA}(t_{praH}-t_{praC}){\mathrm{\γ}}_1+c_{pA}(t_{saH}-t_{saC}){\mathrm{\γ}}_2}{c_{pG}};$

Wherein, θ _nLfor air preheater is without outlet cigarette temperature of leaking out; θ ₁for air preheater inlet flue gas temperature; κ is the mass ratio of air and flue gas in air preheater; c _pAfor the specific heat of air; c _pGfor the specific heat of flue gas; t _praHfor air preheater outlet First air temperature; t _praCfor air preheater entrance First air temperature; t _saHfor air preheater outlet Secondary Air temperature; t _saCfor air preheater entrance Secondary Air temperature; γ ₁for primary air ratio; γ ₂for secondary air ratio.Wherein, primary air ratio γ ₁the ratio of each coal pulverizer inlet air quantity sum and total air can be got; Secondary air ratio γ ₂=α ₁-γ ₁.

During concrete enforcement, also according to First air temperature and Secondary Air temperature, determine that air preheater flue gas leaks out temperature.Fig. 2 is the schematic diagram of three points of storehouse air preheaters in the embodiment of the present invention.Inventor considers, for three points of storehouse air preheaters, due to adjacent First air storehouse, flue gas storehouse and Secondary Air storehouse, so fume side bleed for First air and Secondary Air, therefore to leak out temperature according to First air temperature and Secondary Air temperature determination flue gas in embodiments of the present invention.Specifically determine flue gas leak out temperature time, can also determine in conjunction with the negative pressure of primary air pressure, secondary wind pressure and air preheater exhaust pass.Such as by following formula according to First air temperature and Secondary Air temperature, determine that air preheater flue gas leaks out temperature:

$t_L=\frac{t_{pra}}{1+\sqrt{\frac{p_2-p_{gs}}{p_1-p_{gs}}}}+\frac{t_{sa}}{1+\sqrt{\frac{p_1-p_{gs}}{p_2-p_{gs}}}};$

Wherein, t _lfor air preheater flue gas leaks out temperature, t _prafor First air temperature; t _safor Secondary Air temperature; p ₁for primary air pressure; p ₂for secondary wind pressure; p _gsfor the negative pressure of air preheater exhaust pass.

During concrete enforcement, determining that air preheater to leak out without the gentle air preheater flue gas of outlet cigarette that leaks out after temperature, to leak out temperature without leak out outlet cigarette temperature, boiler actual exhaust gas temperature and air preheater flue gas according to air preheater, determine that air preheater exports air leakage coefficient recruitment.Can various ways be had according to air preheater without leak out outlet cigarette temperature, boiler actual exhaust gas temperature and air preheater flue gas temperature determination air preheater outlet air leakage coefficient recruitment of leaking out, such as, can export air leakage coefficient recruitment by following formula determination air preheater:

$\mathrm{\Δ}\mathrm{\α}=\frac{({\mathrm{\θ}}_{NL}-{\mathrm{\θ}}_2)c_{PG}}{({\mathrm{\θ}}_2-t_L)c_{PA}};$

Wherein, Δ α is air preheater outlet air leakage coefficient recruitment; θ _nLfor air preheater is without outlet cigarette temperature of leaking out; θ ₂for boiler actual exhaust gas temperature; t _lfor air preheater flue gas leaks out temperature.

Finally, according to air preheater outlet air leakage coefficient recruitment and air preheater entrance excess air coefficient, air preheater air leakage rate is determined.Various ways can be had according to air preheater outlet air leakage coefficient recruitment and air preheater entrance excess air coefficient determination air preheater air leakage rate in embodiment, such as by following formula according to air preheater outlet air leakage coefficient recruitment and air preheater entrance excess air coefficient, air preheater air leakage rate can be determined:

${\mathrm{\α}}_L=90\frac{\mathrm{\Δ}\mathrm{\α}}{{\mathrm{\α}}_1+\mathrm{\Δ}\mathrm{\α}};$

Wherein, α _lfor air preheater air leakage rate; Δ α is air preheater outlet air leakage coefficient recruitment; α ₁for air preheater entrance excess air coefficient.

Based on same inventive concept, additionally provide a kind of air preheater air leakage rate determining device in the embodiment of the present invention, as described in the following examples.The principle of dealing with problems due to air preheater air leakage rate determining device is similar to air preheater air leakage rate defining method, and therefore the enforcement of air preheater air leakage rate determining device see the enforcement of air preheater air leakage rate defining method, can repeat part and repeat no more.

Fig. 3 is the schematic diagram of air preheater air leak rate of air curtain determining device in the embodiment of the present invention.As shown in Figure 3, in the embodiment of the present invention, air preheater air leak rate of air curtain determining device can comprise:

The average oxygen amount of entrance obtains module 301, for obtaining the average oxygen amount of air preheater entrance;

Outlet excess air coefficient determination module 302, for according to the average oxygen amount of air preheater entrance, determines air preheater outlet excess air coefficient;

Entrance excess air coefficient determination module 303, for according to air preheater outlet excess air coefficient, determines air preheater entrance excess air coefficient;

Without the outlet cigarette temperature determination module 304 that leaks out, for according to air preheater inlet flue gas temperature, air preheater outlet First air temperature, air preheater outlet Secondary Air temperature, air preheater entrance First air temperature and air preheater entrance Secondary Air temperature, determine that air preheater is without outlet cigarette temperature of leaking out;

Flue gas leaks out temperature determination module 305, for according to First air temperature and Secondary Air temperature, determines that air preheater flue gas leaks out temperature;

Outlet air leakage coefficient recruitment determination module 306, for leaking out temperature without leak out outlet cigarette temperature, boiler actual exhaust gas temperature and air preheater flue gas according to air preheater, determines that air preheater exports air leakage coefficient recruitment;

Air leak rate of air curtain determination module 307, for according to air preheater outlet air leakage coefficient recruitment and air preheater entrance excess air coefficient, determines air preheater air leakage rate; Air preheater is wherein three points of storehouse air preheaters or four points of storehouse air preheaters.

During concrete enforcement, the average oxygen amount of described entrance obtains module 301 and specifically may be used for:

Grid survey is utilized to obtain the average oxygen amount of air preheater entrance;

Or, utilize Oxygen Measuring Instrument on-line measurement to obtain the average oxygen amount of air preheater entrance.

During concrete enforcement, described outlet excess air coefficient determination module 302 specifically to may be used for by following formula according to the average oxygen amount of air preheater entrance, determines air preheater outlet excess air coefficient:

${\mathrm{\α}}_2=\frac{21}{21-O};$

Wherein, α ₂for air preheater outlet excess air coefficient, O is the average oxygen amount of air preheater entrance;

Described entrance excess air coefficient determination module 303 specifically may be used for exporting excess air coefficient by following formula according to air preheater, determines air preheater entrance excess air coefficient:

α ₁＝α ₂-∑Δα′；

Wherein, α ₁for air preheater entrance excess air coefficient, Δ α ' is the air leak rate of air curtain in other place of boiler under rated load except air preheater.

During concrete enforcement, the described nothing outlet cigarette temperature determination module 304 that leaks out specifically to may be used for by following formula, according to air preheater inlet flue gas temperature, air preheater outlet First air temperature, air preheater outlet Secondary Air temperature, air preheater entrance First air temperature and air preheater entrance Secondary Air temperature, determining that air preheater exports cigarette temperature without leaking out:

${\mathrm{\θ}}_{NL}={\mathrm{\θ}}_1-\mathrm{\κ}\·\frac{c_{pA}(t_{praH}-t_{praC}){\mathrm{\γ}}_1+c_{pA}(t_{saH}-t_{saC}){\mathrm{\γ}}_2}{c_{pG}};$

Wherein, θ _nLfor air preheater is without outlet cigarette temperature of leaking out; θ ₁for air preheater inlet flue gas temperature; κ is the mass ratio of air and flue gas in air preheater; c _pAfor the specific heat of air; c _pGfor the specific heat of flue gas; t _praHfor air preheater outlet First air temperature; t _praCfor air preheater entrance First air temperature; t _saHfor air preheater outlet Secondary Air temperature; t _saCfor air preheater entrance Secondary Air temperature; γ ₁for primary air ratio; γ ₂for secondary air ratio.

During concrete enforcement, described flue gas temperature determination module 305 of leaking out specifically to may be used for by following formula according to First air temperature and Secondary Air temperature, determines that air preheater flue gas leaks out temperature:

$t_L=\frac{t_{pra}}{1+\sqrt{\frac{p_2-p_{gs}}{p_1-p_{gs}}}}+\frac{t_{sa}}{1+\sqrt{\frac{p_1-p_{gs}}{p_2-p_{gs}}}};$

Wherein, t _lfor air preheater flue gas leaks out temperature, t _prafor First air temperature; t _safor Secondary Air temperature; p ₁for primary air pressure; p ₂for secondary wind pressure; p _gsfor the negative pressure of air preheater exhaust pass.

During concrete enforcement, described outlet air leakage coefficient recruitment determination module 306 specifically may be used for leaking out temperature without leak out outlet cigarette temperature, boiler actual exhaust gas temperature and air preheater flue gas according to air preheater by following formula, determines that air preheater exports air leakage coefficient recruitment:

$\mathrm{\Δ}\mathrm{\α}=\frac{({\mathrm{\θ}}_{NL}-{\mathrm{\θ}}_2)c_{PG}}{({\mathrm{\θ}}_2-t_L)c_{PA}};$

Wherein, Δ α is air preheater outlet air leakage coefficient recruitment; θ _nLfor air preheater is without outlet cigarette temperature of leaking out; θ ₂for boiler actual exhaust gas temperature; t _lfor air preheater flue gas leaks out temperature.

During concrete enforcement, described air leak rate of air curtain determination module 307 specifically may be used for exporting air leakage coefficient recruitment and air preheater entrance excess air coefficient by following formula according to air preheater, determines air preheater air leakage rate:

${\mathrm{\α}}_L=90\frac{\mathrm{\Δ}\mathrm{\α}}{{\mathrm{\α}}_1+\mathrm{\Δ}\mathrm{\α}};$

Wherein, α _lfor air preheater air leakage rate; Δ α is air preheater outlet air leakage coefficient recruitment; α ₁for air preheater entrance excess air coefficient.

In sum, in the embodiment of the present invention, air preheater air leakage rate is determined according to air preheater outlet air leakage coefficient recruitment and air preheater entrance excess air coefficient, wherein air preheater outlet air leakage coefficient recruitment and air preheater entrance excess air coefficient export oxygen amount without using air preheater in deterministic process, therefore the embodiment of the present invention measures air preheater outlet oxygen amount without the need to adopting gridding method or Oxygen Measuring Instrument, avoid the layout of high level error and the air preheater outlet oxygen amount measuring point measured and bring, air preheater air leakage rate more accurately can be obtained.

Further, Oxygen Measuring Instrument on-line measurement can be utilized to obtain the average oxygen amount of air preheater entrance, and can be implemented in line and measure air leak rate of air curtain in real time, tester need not go to scene, so just saves man power and material.

Those skilled in the art should understand, embodiments of the invention can be provided as method, system or computer program.Therefore, the present invention can adopt the form of complete hardware embodiment, completely software implementation or the embodiment in conjunction with software and hardware aspect.And the present invention can adopt in one or more form wherein including the upper computer program implemented of computer-usable storage medium (including but not limited to magnetic disk memory, CD-ROM, optical memory etc.) of computer usable program code.

The present invention describes with reference to according to the process flow diagram of the method for the embodiment of the present invention, equipment (system) and computer program and/or block scheme.Should understand can by the combination of the flow process in each flow process in computer program instructions realization flow figure and/or block scheme and/or square frame and process flow diagram and/or block scheme and/or square frame.These computer program instructions can being provided to the processor of multi-purpose computer, special purpose computer, Embedded Processor or other programmable data processing device to produce a machine, making the instruction performed by the processor of computing machine or other programmable data processing device produce device for realizing the function of specifying in process flow diagram flow process or multiple flow process and/or block scheme square frame or multiple square frame.

These computer program instructions also can be stored in can in the computer-readable memory that works in a specific way of vectoring computer or other programmable data processing device, the instruction making to be stored in this computer-readable memory produces the manufacture comprising command device, and this command device realizes the function of specifying in process flow diagram flow process or multiple flow process and/or block scheme square frame or multiple square frame.

These computer program instructions also can be loaded in computing machine or other programmable data processing device, make on computing machine or other programmable devices, to perform sequence of operations step to produce computer implemented process, thus the instruction performed on computing machine or other programmable devices is provided for the step realizing the function of specifying in process flow diagram flow process or multiple flow process and/or block scheme square frame or multiple square frame.

Above-described specific embodiment; object of the present invention, technical scheme and beneficial effect are further described; be understood that; the foregoing is only specific embodiments of the invention; the protection domain be not intended to limit the present invention; within the spirit and principles in the present invention all, any amendment made, equivalent replacement, improvement etc., all should be included within protection scope of the present invention.

Claims (14)

1. an air preheater air leakage rate defining method, is characterized in that, described air preheater is three points of storehouse air preheaters, and described method comprises:

Obtain the average oxygen amount of air preheater entrance;

According to the average oxygen amount of air preheater entrance, determine air preheater outlet excess air coefficient;

According to air preheater outlet excess air coefficient, determine air preheater entrance excess air coefficient;

According to air preheater inlet flue gas temperature, air preheater outlet First air temperature, air preheater outlet Secondary Air temperature, air preheater entrance First air temperature and air preheater entrance Secondary Air temperature, determine that air preheater is without outlet cigarette temperature of leaking out;

According to First air temperature and Secondary Air temperature, determine that air preheater flue gas leaks out temperature;

To leak out temperature without leak out outlet cigarette temperature, boiler actual exhaust gas temperature and air preheater flue gas according to air preheater, determine that air preheater exports air leakage coefficient recruitment;

According to air preheater outlet air leakage coefficient recruitment and air preheater entrance excess air coefficient, determine air preheater air leakage rate.

2. the method for claim 1, is characterized in that, the average oxygen amount of described acquisition air preheater entrance, comprising:

Grid survey is utilized to obtain the average oxygen amount of air preheater entrance;

Or, utilize Oxygen Measuring Instrument on-line measurement to obtain the average oxygen amount of air preheater entrance.

3. the method for claim 1, is characterized in that, by following formula according to the average oxygen amount of air preheater entrance, determines air preheater outlet excess air coefficient:

${\mathrm{\α}}_2=\frac{21}{21-O};$

Wherein, α ₂for air preheater outlet excess air coefficient, O is the average oxygen amount of air preheater entrance;

Export excess air coefficient by following formula according to air preheater, determine air preheater entrance excess air coefficient:

α ₁＝α ₂-∑Δα′；

Wherein, α ₁for air preheater entrance excess air coefficient, Δ α ' is the air leak rate of air curtain in other place of boiler under rated load except air preheater.

4. the method for claim 1, it is characterized in that, by following formula according to air preheater inlet flue gas temperature, air preheater outlet First air temperature, air preheater outlet Secondary Air temperature, air preheater entrance First air temperature and air preheater entrance Secondary Air temperature, determine that air preheater is without outlet cigarette temperature of leaking out:

${\mathrm{\θ}}_{NL}={\mathrm{\θ}}_1-\mathrm{\κ}\·\frac{c_{pA}(t_{praH}-t_{praC}){\mathrm{\γ}}_1+c_{pA}(t_{saH}-t_{saC}){\mathrm{\γ}}_2}{c_{pG}};$

Wherein, θ _nLfor air preheater is without outlet cigarette temperature of leaking out; θ ₁for air preheater inlet flue gas temperature; κ is the mass ratio of air and flue gas in air preheater; c _pAfor the specific heat of air; c _pGfor the specific heat of flue gas; t _praHfor air preheater outlet First air temperature; t _praCfor air preheater entrance First air temperature; t _saHfor air preheater outlet Secondary Air temperature; t _saCfor air preheater entrance Secondary Air temperature; γ ₁for primary air ratio; γ ₂for secondary air ratio.

5. the method for claim 1, is characterized in that, by following formula according to First air temperature and Secondary Air temperature, determines that air preheater flue gas leaks out temperature:

$t_L=\frac{t_{pra}}{1+\sqrt{\frac{p_2-p_{gs}}{p_1-p_{gs}}}}+\frac{t_{sa}}{1+\sqrt{\frac{p_1-p_{gs}}{p_2-p_{gs}}}};$

Wherein, t _lfor air preheater flue gas leaks out temperature, t _prafor First air temperature; t _safor Secondary Air temperature; p ₁for primary air pressure; p ₂for secondary wind pressure; p _gsfor the negative pressure of air preheater exhaust pass.

6. the method for claim 1, is characterized in that, to leak out temperature, determine that air preheater exports air leakage coefficient recruitment by following formula according to air preheater without leak out outlet cigarette temperature, boiler actual exhaust gas temperature and air preheater flue gas:

$\mathrm{\Δ}\mathrm{\α}=\frac{({\mathrm{\θ}}_{NL}-{\mathrm{\θ}}_2)c_{PG}}{({\mathrm{\θ}}_2-t_L)c_{PA}};$

Wherein, Δ α is air preheater outlet air leakage coefficient recruitment; θ _nLfor air preheater is without outlet cigarette temperature of leaking out; θ ₂for boiler actual exhaust gas temperature; t _lfor air preheater flue gas leaks out temperature.

7. the method for claim 1, is characterized in that, by following formula according to air preheater outlet air leakage coefficient recruitment and air preheater entrance excess air coefficient, determines air preheater air leakage rate:

${\mathrm{\α}}_L=90\frac{\mathrm{\Δ}\mathrm{\α}}{{\mathrm{\α}}_1+\mathrm{\Δ}\mathrm{\α}};$

Wherein, α _lfor air preheater air leakage rate; Δ α is air preheater outlet air leakage coefficient recruitment; α ₁for air preheater entrance excess air coefficient.

8. an air preheater air leakage rate determining device, is characterized in that, described air preheater is three points of storehouse air preheaters, and described device comprises:

The average oxygen amount of entrance obtains module, for obtaining the average oxygen amount of air preheater entrance;

Outlet excess air coefficient determination module, for according to the average oxygen amount of air preheater entrance, determines air preheater outlet excess air coefficient;

Entrance excess air coefficient determination module, for according to air preheater outlet excess air coefficient, determines air preheater entrance excess air coefficient;

Without the outlet cigarette temperature determination module that leaks out, for according to air preheater inlet flue gas temperature, air preheater outlet First air temperature, air preheater outlet Secondary Air temperature, air preheater entrance First air temperature and air preheater entrance Secondary Air temperature, determine that air preheater is without outlet cigarette temperature of leaking out;

Flue gas leaks out temperature determination module, for according to First air temperature and Secondary Air temperature, determines that air preheater flue gas leaks out temperature;

Outlet air leakage coefficient recruitment determination module, for leaking out temperature without leak out outlet cigarette temperature, boiler actual exhaust gas temperature and air preheater flue gas according to air preheater, determines that air preheater exports air leakage coefficient recruitment;

Air leak rate of air curtain determination module, for according to air preheater outlet air leakage coefficient recruitment and air preheater entrance excess air coefficient, determines air preheater air leakage rate.

9. device as claimed in claim 8, is characterized in that, the average oxygen amount of described entrance obtain module specifically for:

Grid survey is utilized to obtain the average oxygen amount of air preheater entrance;

Or, utilize Oxygen Measuring Instrument on-line measurement to obtain the average oxygen amount of air preheater entrance.

10. device as claimed in claim 8, is characterized in that, described outlet excess air coefficient determination module, specifically for pressing following formula according to the average oxygen amount of air preheater entrance, determines air preheater outlet excess air coefficient:

${\mathrm{\α}}_2=\frac{21}{21-O};$

Wherein, α ₂for air preheater outlet excess air coefficient, O is the average oxygen amount of air preheater entrance;

Described entrance excess air coefficient determination module, specifically for exporting excess air coefficient by following formula according to air preheater, determines air preheater entrance excess air coefficient:

α ₁＝α ₂-∑Δα′；

Wherein, α ₁for air preheater entrance excess air coefficient, Δ α ' is the air leak rate of air curtain in other place of boiler under rated load except air preheater.

11. devices as claimed in claim 8, it is characterized in that, described nothing leaks out outlet cigarette temperature determination module specifically for exporting Secondary Air temperature, air preheater entrance First air temperature and air preheater entrance Secondary Air temperature by following formula according to air preheater inlet flue gas temperature, air preheater outlet First air temperature, air preheater, determines that air preheater is without outlet cigarette temperature of leaking out:

${\mathrm{\θ}}_{NL}={\mathrm{\θ}}_1-\mathrm{\κ}\·\frac{c_{pA}(t_{praH}-t_{praC}){\mathrm{\γ}}_1+c_{pA}(t_{saH}-t_{saC}){\mathrm{\γ}}_2}{c_{pG}};$

Wherein, θ _nLfor air preheater is without outlet cigarette temperature of leaking out; θ ₁for air preheater inlet flue gas temperature; κ is the mass ratio of air and flue gas in air preheater; c _pAfor the specific heat of air; c _pGfor the specific heat of flue gas; t _praHfor air preheater outlet First air temperature; t _praCfor air preheater entrance First air temperature; t _saHfor air preheater outlet Secondary Air temperature; t _saCfor air preheater entrance Secondary Air temperature; γ ₁for primary air ratio; γ ₂for secondary air ratio.

12. devices as claimed in claim 8, is characterized in that, described flue gas leak out temperature determination module specifically for by following formula according to First air temperature and Secondary Air temperature, determine that air preheater flue gas leaks out temperature:

$t_L=\frac{t_{pra}}{1+\sqrt{\frac{p_2-p_{gs}}{p_1-p_{gs}}}}+\frac{t_{sa}}{1+\sqrt{\frac{p_1-p_{gs}}{p_2-p_{gs}}}};$

Wherein, t _lfor air preheater flue gas leaks out temperature, t _prafor First air temperature; t _safor Secondary Air temperature; p ₁for primary air pressure; p ₂for secondary wind pressure; p _gsfor the negative pressure of air preheater exhaust pass.

13. devices as claimed in claim 8, it is characterized in that, described outlet air leakage coefficient recruitment determination module, specifically for leaking out temperature without leak out outlet cigarette temperature, boiler actual exhaust gas temperature and air preheater flue gas according to air preheater by following formula, determines that air preheater exports air leakage coefficient recruitment:

$\mathrm{\Δ}\mathrm{\α}=\frac{({\mathrm{\θ}}_{NL}-{\mathrm{\θ}}_2)c_{PG}}{({\mathrm{\θ}}_2-t_L)c_{PA}};$

Wherein, Δ α is air preheater outlet air leakage coefficient recruitment; θ _nLfor air preheater is without outlet cigarette temperature of leaking out; θ ₂for boiler actual exhaust gas temperature; t _lfor air preheater flue gas leaks out temperature.

14. devices as claimed in claim 8, is characterized in that, described air leak rate of air curtain determination module, specifically for exporting air leakage coefficient recruitment and air preheater entrance excess air coefficient by following formula according to air preheater, determines air preheater air leakage rate:

${\mathrm{\α}}_L=90\frac{\mathrm{\Δ}\mathrm{\α}}{{\mathrm{\α}}_1+\mathrm{\Δ}\mathrm{\α}};$

Wherein, α _lfor air preheater air leakage rate; Δ α is air preheater outlet air leakage coefficient recruitment; α ₁for air preheater entrance excess air coefficient.