CN104298842A - Method for detecting heat economic life of industrial boiler - Google Patents

Abstract

The invention provides a method for detecting the heat economic life of an industrial boiler. The method comprises the steps that an industrial boiler available energy balance physical model is established, an industrial boiler available energy economic balance physical model is established, and an industrial boiler heat economic life mathematic model is established; the changing relationship between industrial boiler available energy efficiency and heating loads is determined, the changing relationship between industrial boiler heat loads and time is determined, and the changing relationship between industrial boiler available energy efficiency and time is determined; the heat economic life of the industrial boiler is solved. According to the method for detecting the heat economic life of the industrial boiler, an effective processing method of the changing relationship between the industrial boiler available energy efficiency and the heat loads and the relationship between the industrial boiler available energy efficiency and the operation time is provided, and the method has the advantages of being simple, practical, easy to be programmed, capable of accurately determining the heat economic life of the industrial boiler, and capable of effectively supporting site production activities.

Description

The detection method of Industrial Boiler thermoeconomic life

Technical field

The present invention relates to the detection method of boiler, particularly relate to a kind of detection method of Industrial Boiler thermoeconomic life.

Background technology

Industrial Boiler is energy consumption equipment important in productive life, after Industrial Boiler puts into operation, As time goes on, due to the wearing and tearing of parts, the corrosion and scaling of heating surface, many-sided reason such as characteristic variations, material aging of insulation material, cause the available energy (exergy of industrial boiler system, the available energy of heating power system working medium, for determining the part likely making useful work in certain designated state lower given energy) efficiency declines, maintenance cost increases, and the economic benefit that system is brought declines.After industrial boiler system puts into operation sometime, not by safeguarding or the measure of maintenance, system is reruned, and this moment has been called serviceable life of system.That is, when the serviceable life that industrial boiler system runs to it at the end, Industrial Boiler must upgrade.The renewal of existing Industrial Boiler is according to mainly to be as the criterion the serviceable life of said system, and this renewal foundation to Industrial Boiler, also exists following shortcoming or deficiency: the economic benefit 1. not considering Industrial Boiler, brings huge economic loss to country and enterprise; 2. technical equipment is caused to fall behind; 3. waste energy and maintenance fund; 4. the needs of modern business development can not be adapted to.We have invented a kind of detection method of new Industrial Boiler thermoeconomic life for this reason, solve above technical matters.

Summary of the invention

The object of this invention is to provide a kind of detection method determining the Industrial Boiler thermoeconomic life of the thermoeconomic life of Industrial Boiler.

Object of the present invention realizes by following technical measures: the detection method of this Industrial Boiler thermoeconomic life comprises: step 1, and setting up Industrial Boiler can with balancing physical model; Step 2, sets up Industrial Boiler and can use energy economic balance physical model; Step 3, sets up Industrial Boiler thermoeconomic life mathematical model; Step 4, determines the variation relation of Industrial Boiler available egress time with thermal load; Step 5, determines Industrial Boiler thermal load relation over time; Step 6, determines Industrial Boiler available egress time relation over time; And step 7, solve the thermoeconomic life of Industrial Boiler.

Object of the present invention also realizes by following technical measures:

In step 1, Industrial Boiler can be with energy balance equation:

e _xsup=e _xout+e _xl0+e _xl1+e _xl2+e _xl3+e _xl4+e _xl5

In formula, e _xsupfor Industrial Boiler consumes the available energy of input of unit of fuel, kilojoule per kilogram; e _xoutthe available energy of output for Industrial Boiler unit product, kilojoule per kilogram; e _xl0for Industrial Boiler conducts heat the available loss of energy, kilojoule per kilogram; e _xl1for combustion of industrial boiler can use the loss of energy, kilojoule per kilogram; e _xl2for Industrial Boiler is discharged fume the available loss of energy, kilojoule per kilogram; e _xl3for Industrial Boiler chemically incomplete combustion can use the loss of energy, kilojoule per kilogram; e _xl4for Industrial Boiler surface radiating can use the loss of energy, kilojoule per kilogram; e _xl5for Industrial Boiler physical heat of ash dregs can use the loss of energy, kilojoule per kilogram.

In step 2, Industrial Boiler can be with energy economic balance equation:

c _sup·E _xsup+C _eq+C _m=c _out·E _xout

In formula, E _xsupfor Industrial Boiler year supplies available energy, kilojoule/year; E _xoutfor Industrial Boiler product year exports available energy, kilojoule/year; c _supfor Industrial Boiler supply available energy unit price, unit/kilojoule; c _outfor Industrial Boiler output of products can use energy unit price, unit/kilojoule; C _eqfor Industrial Boiler investment of equipment year depreciation cost, unit/year; C _mfor Industrial Boiler equipment year operation control expense, the cost of labor comprising maintenance of equipment, material consumption, managerial cost and share, unit/year.

In step 3, the available energy econometric function that this Industrial Boiler thermoeconomic life mathematical model is is variable with time t, this Industrial Boiler thermoeconomic life mathematical model is:

$Y\left(\mathrm{\τ}\right)=\∫_0^{\mathrm{\τ}}[{\mathrm{\Σc}}_{\mathrm{out}}\left(t\right)\·E_{\mathrm{xout}}\left(t\right)-{\mathrm{\Σc}}_{\sup }\left(t\right)\·E_{\mathrm{xsup}}\left(t\right)-C_{\mathrm{eq}}\left(t\right)-C_m\left(t\right)]\mathrm{dt}$

When industrial boiler operation to the τ time after, the economic benefit that Industrial Boiler obtains within this time period is Y (τ), if industrial boiler operation τ ₀time, Industrial Boiler equipment creates maximum economic benefit, then τ ₀be the Industrial Boiler optimal economic life-span.

In step 4, under different load, adopt available egress time positive balance method of testing, determine one group of available egress time value, utilizing least square method to obtain this Industrial Boiler available egress time with the variation relation of thermal load is η _ex=f ₁(X).

In step 4, these available egress time positive balance method of testing concrete steps of Industrial Boiler comprise:

A () uses the sampling method thief coal of traditional Industrial Boiler;

B () uses the coal sample preparation method of traditional Industrial Boiler to prepare coal sample;

(c) metering fuel;

The quantity of steam of (d) metering steam boiler;

E () measures hot-water boiler quantity of circulating water;

F () measures industrial boiler water-supply pressure;

G () measures industrial boiler steam pressure;

H () measures feed temperature and the outlet steam temperature of steam boiler;

(i) measure the inflow temperature of hot-water boiler and go out water temperature;

J () measures the air themperature into stokehold;

(k) measures ambient temperature;

L () measures saturated steam wetness;

M () calculates Industrial Boiler positive balance available egress time; And

N () utilizes least square curve fit to determine the variation relation of this Industrial Boiler available egress time with thermal load.

In step (m), Industrial Boiler input is available can computing formula be:

e _xsup=e _xf+e _xwl+e _xrx+e _xzy

In formula, e _xsupthe available energy of input for Industrial Boiler, unit is kJ/kg; e _xffor the fuel entering stove can use energy, unit is kJ/kg; e _xwlfor heating fuel or external heat can use energy, unit is kJ/kg; e _xrxfor the physical thermal of fuel can use energy, unit is kJ/kg; e _xzythe heat brought into for personal steam can use energy, and unit is kJ/kg;

Steam boiler available egress time positive balance computing formula is:

${\mathrm{\η}}_{\mathrm{ex}}=\frac{H_s-H_w-T_0(S_s-S_w)}{{\mathrm{Be}}_{\mathrm{xsup}}}\×100\%$

In formula, η _exfor the positive balance available egress time of steam boiler, %; H _scan energy be used, kJ/h for steam boiler exports steam;

H _wfor steam boiler feeds water available energy, kJ/h; S _sfor steam boiler exports entropy of evaporation, kJ/ (hK); S _wfor steam boiler feedwater entropy, kJ/ (hK); B is the Fuel Consumption of steam boiler, kg/h; T ₀for environment temperature, K;

Hot-water boiler available egress time positive balance computing formula is:

${\mathrm{\η}}_{\mathrm{ex}}=\frac{H_{w2}-H_{w1}-T_0(S_{w2}-S_{w1})}{{\mathrm{Be}}_{\mathrm{xsup}}}$

In formula, H _w1for hot-water boiler feeds water available energy, kJ/h; H _w2for hot-water boiler water outlet can use energy, kJ/h; S _w1for hot-water boiler feedwater entropy, kJ/ (hK); S _w2for hot-water boiler water outlet entropy, kJ/ (hK).

In steps of 5, utilize the historical statistical data of industrial boiler operation, going out that this Industrial Boiler thermal load closes over time with least square fitting is X=f ₂(t).

In step 6, utilize historical statistics or the test data of industrial boiler operation, determining that this Industrial Boiler available egress time closes over time by semilog data processing and simple linear regression analysis is η _ex=f ₃(t).

In step 7, determine that the relational expression that solves of the thermoeconomic life of this Industrial Boiler is:

$Y\left(t\right)=\∫_0^t[{\mathrm{\Σc}}_{\mathrm{out}}\left(t\right)\·f_4(X,{\mathrm{\η}}_{\mathrm{ex}}){-\mathrm{\Σc}}_{\sup }\left(t\right)\·f_5(X,{\mathrm{\η}}_{\mathrm{ex}})-C_{\mathrm{eq}}\left(t\right){-C}_m\left(t\right)]\mathrm{dt};$

Trial and error procedure is adopted to solve the thermoeconomic life of this Industrial Boiler.

The detection method of the Industrial Boiler thermoeconomic life in the present invention, use thermoeconomics principle, the research Exergy Analysis physics of Industrial Boiler and mathematical model and available can economic analysis physics and mathematical model, by setting up Industrial Boiler available egress time with after load variations relation and Industrial Boiler available egress time in time variation relation, set up the mathematic(al) representation of Industrial Boiler thermoeconomic life, thus determine the thermoeconomic life of Industrial Boiler, and effectively overcome or avoid the shortcoming that exists in above-mentioned prior art or deficiency.The detection method of the Industrial Boiler thermoeconomic life in the present invention compared with prior art tool has the following advantages: 1, apply thermoeconomics principle, theoretical advanced, clear concept; 2, the effective treating method of the variation relation of Industrial Boiler available egress time and thermal load and working time is proposed; 3, simple and practical, be easy to sequencing, can determine the thermoeconomic life of Industrial Boiler exactly, the update for Industrial Boiler provides the foundation of science; 4, effectively produced on-site activity is supported.

Accompanying drawing explanation

Fig. 1 is the process flow diagram of a specific embodiment of the detection method of Industrial Boiler thermoeconomic life of the present invention;

Fig. 2 is that in a specific embodiment of the detection method of Industrial Boiler thermoeconomic life of the present invention, Industrial Boiler can with the schematic diagram that can balance physical model;

Fig. 3 is the schematic diagram that in a specific embodiment of the detection method of Industrial Boiler thermoeconomic life of the present invention, Industrial Boiler can use energy economic balance physical model;

Fig. 4 is be Industrial Boiler thermoeconomic life C language software for calculation schematic flow sheet in a specific embodiment of the detection method of Industrial Boiler thermoeconomic life of the present invention;

Fig. 5 is 20t/h oil-fired steam boiler annual earnings relation curve schematic diagram over time in a specific embodiment of the detection method of Industrial Boiler thermoeconomic life of the present invention.

Embodiment

For making above and other object of the present invention, feature and advantage can become apparent, cited below particularly go out preferred embodiment, and coordinate institute's accompanying drawings, be described in detail below.

As shown in Figure 1, Fig. 1 is the process flow diagram of the detection method of Industrial Boiler thermoeconomic life of the present invention.In step 101, setting up Industrial Boiler can with balancing physical model.As shown in Figure 2, Fig. 2 is that in a specific embodiment of the detection method of Industrial Boiler thermoeconomic life of the present invention, Industrial Boiler can with the schematic diagram that can balance physical model.Industrial Boiler can be with energy balance equation:

e _xsup=e _xout+e _xl0+e _xl1+e _xl2+e _xl3+e _xl4+e _xl5

In formula, e _xsupfor Industrial Boiler consumes the available energy of input of unit of fuel, kilojoule per kilogram; e _xoutthe available energy of output for Industrial Boiler unit product, kilojoule per kilogram; e _xl0for Industrial Boiler conducts heat the available loss of energy, kilojoule per kilogram; e _xl1for combustion of industrial boiler can use the loss of energy, kilojoule per kilogram; e _xl2for Industrial Boiler is discharged fume the available loss of energy, kilojoule per kilogram; e _xl3for Industrial Boiler chemically incomplete combustion can use the loss of energy, kilojoule per kilogram; e _xl4for Industrial Boiler surface radiating can use the loss of energy, kilojoule per kilogram; e _xl5for Industrial Boiler physical heat of ash dregs can use the loss of energy, kilojoule per kilogram.Flow process enters into step 102.

In step 102, set up Industrial Boiler and can use energy economic balance physical model.As shown in Figure 3, Fig. 3 is the schematic diagram that in a specific embodiment of the detection method of Industrial Boiler thermoeconomic life of the present invention, Industrial Boiler can use energy economic balance physical model.Industrial Boiler can use energy economic balance equation with energy economic balance mathematical model and Industrial Boiler, the equation left side supplies available energy expense, Industrial Boiler investment of equipment year depreciation cost and Industrial Boiler equipment year operation control expense by Industrial Boiler, the cost of labor composition that Industrial Boiler equipment year operation control expense comprises maintenance of equipment, material consumption, managerial cost and shares, can with can expense form by output of products on the right of equation.Industrial Boiler can be with energy economic balance equation:

c _sup·E _xsup+C _eq+C _m=c _out·E _xout

In formula, E _xsupfor Industrial Boiler year supplies available energy, kilojoule/year; E _xoutfor Industrial Boiler product year exports available energy, kilojoule/year; c _supfor Industrial Boiler supply available energy unit price, unit/kilojoule; c _outfor Industrial Boiler output of products can use energy unit price, unit/kilojoule; C _eqfor Industrial Boiler investment of equipment year depreciation cost, unit/year; C _mfor Industrial Boiler equipment year operation control expense, the cost of labor comprising maintenance of equipment, material consumption, managerial cost and share, unit/year.Flow process enters into step 103.

In step 103, set up Industrial Boiler thermoeconomic life mathematical model.The available energy econometric function that Industrial Boiler thermoeconomic life mathematical model is is variable with time t, its mathematical model is:

$Y\left(\mathrm{\τ}\right)=\∫_0^{\mathrm{\τ}}[{\mathrm{\Σc}}_{\mathrm{out}}\left(t\right)\·E_{\mathrm{xout}}\left(t\right)-{\mathrm{\Σc}}_{\sup }\left(t\right)\·E_{\mathrm{xsup}}\left(t\right)-C_{\mathrm{eq}}\left(t\right)-C_m\left(t\right)]\mathrm{dt}$

When industrial boiler operation to the τ time after, the economic benefit that Industrial Boiler obtains within this time period is Y (τ).If industrial boiler operation τ ₀time, Industrial Boiler equipment creates maximum economic benefit, then τ ₀be the Industrial Boiler optimal economic life-span.Flow process enters into step 104.

In step 104, determine the variation relation of Industrial Boiler available egress time with thermal load: η _ex=f ₁(X), adopt available egress time positive balance method of testing to determine, namely under different load, adopt available egress time positive balance method of testing, determine one group of available egress time value, utilize least square method to obtain the funtcional relationship η of available egress time and thermal load _ex=f ₁(X).

Industrial Boiler available egress time positive balance method of testing concrete steps are as follows: the sampling of (1) coal, use the sampling method of traditional Industrial Boiler; (2) coal sample preparation, uses the coal sample preparation method of traditional Industrial Boiler; (3) metering of fuel; (4) metering of steam boiler quantity of steam.With ultrasonic flow rate measurement amount feedwater flow, determine quantity of steam by measuring industrial boiler water-supply flow; (5) hot-water boiler quantity of circulating water adopts ultrasonic flow meter to measure; (6) industrial boiler water-supply pressure adopts precision pressure gauge to measure; (7) industrial boiler steam pressure adopts precision pressure gauge to measure; (8) feed temperature of steam boiler and outlet steam temperature adopt mercury thermometer to measure; (9) hot-water boiler inflow temperature and go out water temperature adopt platinum-resistance thermometer measure; (10) air themperature entering stokehold adopts thermal resistance thermometer to measure; (11) environment temperature adopts mercury thermometer to measure; (12) measurement of saturated steam wetness, adopts chlorine root method to measure; (13) calculating of Industrial Boiler positive balance available egress time: 1. Industrial Boiler input available energy computing formula:

e _xsup=e _xf+e _xwl+e _xrx+e _xzy

In formula, e _xsupthe available energy of input for Industrial Boiler, unit is kJ/kg; e _xffor the fuel entering stove can use energy, unit is kJ/kg; e _xwlfor heating fuel or external heat can use energy, unit is kJ/kg; e _xrxfor the physical thermal of fuel can use energy, unit is kJ/kg; e _xzythe heat brought into for personal steam can use energy, and unit is kJ/kg;

2. steam boiler available egress time positive balance computing formula:

${\mathrm{\η}}_{\mathrm{ex}}=\frac{H_s-H_w-T_0(S_s-S_w)}{{\mathrm{Be}}_{\mathrm{xsup}}}\×100\%$

In formula, η _exfor the positive balance available egress time of steam boiler, %; H _scan energy be used, kJ/h for steam boiler exports steam;

H _wfor steam boiler feeds water available energy, kJ/h; S _sfor steam boiler exports entropy of evaporation, kJ/ (hK); S _wfor steam boiler feedwater entropy, kJ/ (hK); B is the Fuel Consumption of steam boiler, kg/h; T ₀for environment temperature, K;

3. hot-water boiler available egress time positive balance computing formula:

${\mathrm{\η}}_{\mathrm{ex}}=\frac{H_{w2}-H_{w1}-T_0(S_{w2}-S_{w1})}{{\mathrm{Be}}_{\mathrm{xsup}}}$

In formula, H _w1for hot-water boiler feeds water available energy, kJ/h; H _w2for hot-water boiler water outlet can use energy, kJ/h; S _w1for hot-water boiler feedwater entropy, kJ/ (hK); S _w2for hot-water boiler water outlet entropy, kJ/ (hK).

(14) funtcional relationship of Industrial Boiler available egress time and thermal load utilizes least square curve fit to determine.Its concrete steps are as follows:

1. each data point (X of n is recorded by Industrial Boiler available egress time and thermal load test _i, η _{ex, i}) (i=1,2 ..., n), require that (m-1) secondary least square fitting polynomial expression is:

f ₁(X)=a ₁+a ₂X+a ₃X ²+···+a _mX ^m1

Wherein m≤n and m≤20.

2. polynomial fitting is each orthogonal polynomial Q _j(X) (j=1,2 ..., linear combination m), namely

f ₁(X)=q ₁Q ₁(X)+q ₂Q ₂(X)+···+q _mQ _m(X)

Wherein Q _j(X) (j=1,2 ..., m) constructed by following recursion formula:

Q ₁(X)=1

Q ₂(X)=(X－a ₂)

Q _j+1(X)=(X－a _j+1)Q _j(X)－β _jQ _j－1(X)，j=2,3,…,m－1

If establish

$d_j=\underset{i=1}{\overset{n}{\mathrm{\Σ}}}{Q}_j^2\left(X_i\right),j=\mathrm{1,2},\·\·\·,m$

Then

$a_{j+1}=\underset{i=1}{\overset{n}{\mathrm{\Σ}}}{X}_i{Q}_j^2\left(X_i\right)/d_j,j=\mathrm{1,2},\·\·\·,m-1$

β _j=d _j/d _j－1，j=2,3,…,m－1

By the polynomial expression { Q of upper surface construction _j(j=1,2 ..., be m) mutually orthogonal, according to the principle of least square, can obtain

$q_j={\mathrm{\Σ\η}}_{\mathrm{ex},i}{Q}_j\left(X_i\right)/d_j,j=1,2,\·\·\·,m$

Finally can change into general m-1 order polynomial

f ₁(X)=a ₁+a ₂X+a ₃X ²+···+a _mX ^m－1

Concrete calculation procedure is as follows:

A, Q ₁(X)=1, can obtain

$b_1=1,d_1=n,q_1=\underset{i=1}{\overset{n}{\mathrm{\Σ}}}{\mathrm{\η}}_{\mathrm{ex},i}/d_1,a=\underset{i=1}{\overset{n}{\mathrm{\Σ}}}{X}_i/d_1$

a ₁=q ₁b ₁

B, Q ₂(X)=(X-a ₂), can obtain

t ₂=1，t ₁=－a

$d_2=\underset{i=1}{\overset{n}{\mathrm{\Σ}}}{Q}_2^2\left(X_i\right),q_2=\underset{i=1}{\overset{n}{\mathrm{\Σ}}}{\mathrm{\η}}_{\mathrm{ex},i}{Q}_2\left(X_i\right)/d_2$

$a=\underset{i=1}{\overset{n}{\mathrm{\Σ}}}{X}_i{Q}_1^2\left(X_i\right)/d_2,\mathrm{\β}=d_2/d_1$

$a_2=q_2{t}_2,q_2{t}_1+a_1\⇒a_1$

C, for j=3,4 ..., m, makes following step:

Q _j(X)=(X－a)Q _j－1(X)+βQ _j－2(X)

=(X－a)(t _j－1X ^j－2+···+t ₂X+t ₁)－β(b _j－2X ^j－3+···+b ₂X+b ₁)

Make s _jx ^j-1+ s _j-1x ^j-2++ s ₂x+s ₁

S in formula _kcalculated by following recursion formula:

$\left\{\begin{array}{c}{s}_j=t_{j-1}\\ s_{j-1}={-\mathrm{at}}_{j-1}+t_{j-2}\\ s_k={-\mathrm{at}}_k+t_{k-1}-{\mathrm{\βb}}_k,k=j-2,\·\·\·,2\\ s_1={-\mathrm{at}}_1-{\mathrm{\βb}}_1\end{array}\right.$

Calculate again

$d_j=\underset{i=1}{\overset{n}{\mathrm{\Σ}}}{Q}_j^2\left(X_i\right),q_j=\underset{i=1}{\overset{n}{\mathrm{\Σ}}}{\mathrm{\η}}_{\mathrm{ex},i}{Q}_j\left(X_i\right)/d_j$

$a=\underset{i=1}{\overset{n}{\mathrm{\Σ}}}{X}_i{Q}_j^2\left(X_i\right)/d_j,\mathrm{\β}=d_j/d_{j-1}$

Corresponding a can be calculated thus _k:

$\left\{\begin{array}{c}{a}_i=q_j{s}_j\\ a_k+q_j{s}_k\⇒a_k,k=j-1,\·\·\·,1\end{array}\right.$

And

$\left\{\begin{array}{c}{t}_j=s_j\\ b_k=t_k,t_k=s_k,k=j-1,\·\·\·,1\end{array}\right.$

In actual computation process, in order to prevent computing from overflowing, X _iwith

$X_i^{\′}=X_i-\stackrel{\‾}{X},i=\mathrm{1,2},\·\·\·,n$

Replace.

Wherein

$\stackrel{\‾}{X}=\underset{i=1}{\overset{n}{\mathrm{\Σ}}}{X}_i/n$

Now, the form of polynomial fitting is

$f_1\left(X\right)=a_1+a_2(X-\stackrel{\‾}{X})+a_3{(X-\stackrel{\‾}{X})}^2+\·\·\·+a_m{(X-\stackrel{\‾}{X})}^{m-1}$

Flow process enters into step 105.

In step 105, determine Industrial Boiler thermal load relation over time: X=f ₂t (), utilizes the historical statistical data of industrial boiler operation, go out thermal load funtcional relationship X=f in time with least square fitting ₂(t).Flow process enters into step 106.

In step 106, determine Industrial Boiler available egress time relation over time: η _ex=f ₃t (), utilizes historical statistics or the test data of industrial boiler operation, determine Industrial Boiler available egress time funtcional relationship η in time by semilog data processing and simple linear regression analysis _ex=f ₃(t).Its concrete steps are, under a certain Industrial Boiler thermal load, and given n data point (t _i, η _{ex, i}) (i=1,2 ... n), function is used

η _ex=bz ^at，z＞0

Carry out matching.In order to ask fitting parameter, take the logarithm in both sides, namely

log _zη _ex=log _zb+at

Order

${\tilde{n}}_{\mathrm{ex}}=\tilde{a}\tilde{t}+\tilde{b}$

Wherein

${\widetilde{\mathrm{\η}}}_{\mathrm{ex}}={\log }_z{\mathrm{\η}}_{\mathrm{ex}},\tilde{t}=t,\tilde{a}=a,\tilde{b}={\log }_{z}b$

Now, turn to n data point make linear fit, concrete steps are as follows:

Stochastic variable with independent variable change.Known n group observation data (i=1,2 ..., n), use straight line

${\widetilde{\mathrm{\η}}}_{\mathrm{ex}}=\tilde{a}\tilde{t}+\tilde{b}$

Do regretional analysis.Wherein with for regression coefficient.

For determining regression coefficient with adopt least square method, namely make

$q=\mathrm{\Σ}{[{\widetilde{\mathrm{\η}}}_{\mathrm{ex},i}-(\tilde{a}\widetilde{t_i}+\tilde{b})]}^2$

Reach minimum.According to extremum principle, with meet following equations:

$\frac{\∂q}{\∂\tilde{a}}=2\underset{i=1}{\overset{n}{\mathrm{\Σ}}}[{\widetilde{\mathrm{\η}}}_{\mathrm{ex},i}-(\tilde{a}\widetilde{t_i}+\tilde{b})](-\widetilde{t_i})=0$

$\frac{\∂q}{\∂\tilde{b}}=2\underset{i=1}{\overset{n}{\mathrm{\Σ}}}[{\widetilde{\mathrm{\η}}}_{\mathrm{ex},i}-(\tilde{a}\widetilde{t_i}+\tilde{b})](-1)=0$

Thus solve

$\tilde{a}=\frac{d\tilde{t}{\widetilde{\mathrm{\η}}}_{\mathrm{ex}}}{d\tilde{t}}\widetilde{,b}={\stackrel{\‾}{\widetilde{\mathrm{\η}}}}_{\mathrm{ex}}-\tilde{a}\stackrel{\‾}{\tilde{t}}$

Wherein

$\stackrel{\‾}{\tilde{t}}=\underset{i=1}{\overset{n}{\mathrm{\Σ}}}\frac{\widetilde{t_i}}{n},{\stackrel{\‾}{\widetilde{\mathrm{\η}}}}_{\mathrm{ex}}=\underset{i=1}{\overset{n}{\mathrm{\Σ}}}\frac{{\widetilde{\mathrm{\η}}}_{\mathrm{ex}}}{n}$

$d\tilde{t}=\mathrm{\Σ}{(\widetilde{t_i}-\stackrel{\‾}{\tilde{t}})}^2,d\tilde{t}{\widetilde{\mathrm{\η}}}_{\mathrm{ex}}=\mathrm{\Σ}(\widetilde{t_i}-\stackrel{\‾}{\tilde{t}})({\widetilde{\mathrm{\η}}}_{\mathrm{ex},i}-{\stackrel{\‾}{\widetilde{\mathrm{\η}}}}_{\mathrm{ex}})$

Obtain with after, just can obtain

$a=\tilde{a}{,b=z}^{\tilde{b}}$

Flow process enters into step 107.

In step 107, that determines thermoeconomic life solves relational expression:

$Y\left(t\right)=\∫_0^t[{\mathrm{\Σc}}_{\mathrm{out}}\left(t\right)\·f_4(X,{\mathrm{\η}}_{\mathrm{ex}})-{\mathrm{\Σc}}_{\sup }\left(t\right)\·f_5(X,{\mathrm{\η}}_{\mathrm{ex}})-C_{\mathrm{eq}}\left(t\right)-C_m\left(t\right)]\mathrm{dt}$

Above formula can solve with the thermoeconomic life of trial and error procedure to Industrial Boiler.In one embodiment, establishment C language software for calculation, and implementation goal is calculated.Concrete calculating as shown in Figure 4.Solve relational expression for mathematical model with thermoeconomic life, with the industrial boiler operation time for independent variable, with year economic benefit for variable: the economic benefit 1. calculating First Year; 2. calculate the economic benefit of t always; 3. t is compared _iyear total economic benefit and to t _i-1total economic benefit in year; If 4. to t _itotal economic benefit be less than t _i-1total economic benefit in year; 5. result of calculation is exported, t _i-1be Industrial Boiler thermoeconomic life.

Embodiment

The testing process of Industrial Boiler to its thermoeconomic life below in conjunction with actual motion is illustrated:

1. existing determine its thermoeconomic life for a 20t/h fuel oil wet steamer (its rated pressure is for 2.5Mpa), to be the load variations rule run in a day be the operation characteristic of this steam boiler: X=0.308+0.121t-0.00504t ²; [t is the time, and span is (0 ~ 24h)].This steam boiler load variations to the variation relation of available egress time is:

η _ex(X)=0.115+0.750·X－0.406·X ²+0.003·X ³。

The test data that table 1 20t/h fuel oil wet steamer available egress time changes with thermal load

The time dependent historical data of table 2 20t/h fuel oil wet steamer available egress time

Table 2 continues

This wet steamer closes over time at run duration available egress time:

${\mathrm{\η}}_{\mathrm{ex}}\left(t\right)=0.463\×e^{-0.06{\·t}^{0.58}}$

This steam boiler first cost is 900,000 yuan, and in thermoeconomic life computation process, the first cost per year method of sharing equally is considered, shares equally and is limited to 20 years year, and namely annual first cost is C _eq=4.50(ten thousand yuan/year), this steam boiler in the operation control expense of run duration is: C _m=5.8+0.8t(ten thousand yuan/year).This steam boiler fuel (heavy oil) is available can unit price be: c _sup=5.83 × 10 ^-5(unit/kilojoule) or (), this steam boiler exports steam and can be with energy unit price: c _out=1.75 × 10 ^-4(unit/kilojoule) or ($/kJ).

2. the year economic benefit calculation formula of this steam boiler is:

$Y\left(t\right)=\∫_0^t\{\underset{i=0}{\overset{24}{\mathrm{\Σ}}}7620.480X\×[2715.100+180.175X{2124.323e}^{-(6.006\×{10}^{-4}+5.000\×{10}^{-3}{X}^{0.02})}]$

$-\underset{i=0}{\overset{24}{\mathrm{\Σ}}}\frac{2540.160X\×[2715.100+180.175X-2124.323e^{-(6.006\×{10}^{-4}+5.000\×{10}^{-3}{X}^{0.02})}}{(0.115+0.750X0.406X^2+0.003X^3)e^{0.06t^{0.58}}}$

$-10.3-0.8t\}\mathrm{dt}.$

In formula, Y is the annual earnings of steam boiler, unit/year; X is the rate of load condensate of steam boiler; T is steam boiler thermoeconomic life computing time, and unit is year.

3. the result of calculation of this 20t/h steam boiler thermoeconomic life is in table 3.

The result of calculation of table 3 20t/h steam boiler thermoeconomic life

4. these steam boiler annual earnings over time relation curve as shown in Figure 5, Fig. 5 is 20t/h oil-fired steam boiler annual earnings relation curve schematic diagram over time in a specific embodiment of the detection method of Industrial Boiler thermoeconomic life of the present invention.

Claims (10)

1. the detection method of Industrial Boiler thermoeconomic life, is characterized in that, the detection method of this Industrial Boiler thermoeconomic life comprises:

Step 1, setting up Industrial Boiler can with balancing physical model;

Step 2, sets up Industrial Boiler and can use energy economic balance physical model;

Step 3, sets up Industrial Boiler thermoeconomic life mathematical model;

Step 4, determines the variation relation of Industrial Boiler available egress time with thermal load;

Step 5, determines Industrial Boiler thermal load relation over time;

Step 6, determines Industrial Boiler available egress time relation over time; And

Step 7, solves the thermoeconomic life of Industrial Boiler.

2. the detection method of Industrial Boiler thermoeconomic life according to claim 1, is characterized in that, in step 1, Industrial Boiler can be with energy balance equation:

e _xsup=e _xout+e _xl0+e _xl1+e _xl2+e _xl3+e _xl4+e _xl5

In formula, e _xsupfor Industrial Boiler consumes the available energy of input of unit of fuel, kilojoule per kilogram; e _xoutthe available energy of output for Industrial Boiler unit product, kilojoule per kilogram; e _xl0for Industrial Boiler conducts heat the available loss of energy, kilojoule per kilogram; e _xl1for combustion of industrial boiler can use the loss of energy, kilojoule per kilogram; e _xl2for Industrial Boiler is discharged fume the available loss of energy, kilojoule per kilogram; e _xl3for Industrial Boiler chemically incomplete combustion can use the loss of energy, kilojoule per kilogram; e _xl4for Industrial Boiler surface radiating can use the loss of energy, kilojoule per kilogram; e _xl5for Industrial Boiler physical heat of ash dregs can use the loss of energy, kilojoule per kilogram.

3. the detection method of Industrial Boiler thermoeconomic life according to claim 2, is characterized in that, in step 2, Industrial Boiler can be with energy economic balance equation:

c _sup·E _xsup+C _eq+C _m=c _out·E _xout

In formula, E _xsupfor Industrial Boiler year supplies available energy, kilojoule/year; E _xoutfor Industrial Boiler product year exports available energy, kilojoule/year; c _supfor Industrial Boiler supply available energy unit price, unit/kilojoule; c _outfor Industrial Boiler output of products can use energy unit price, unit/kilojoule; C _eqfor Industrial Boiler investment of equipment year depreciation cost, unit/year; C _mfor Industrial Boiler equipment year operation control expense, the cost of labor comprising maintenance of equipment, material consumption, managerial cost and share, unit/year.

4. the detection method of Industrial Boiler thermoeconomic life according to claim 3, it is characterized in that, in step 3, the available energy econometric function that this Industrial Boiler thermoeconomic life mathematical model is is variable with time t, this Industrial Boiler thermoeconomic life mathematical model is:

$Y\left(\mathrm{\τ}\right)=\∫_0^{\mathrm{\τ}}[{\mathrm{\Σc}}_{\mathrm{out}}\left(t\right)\·E_{\mathrm{xout}}\left(t\right)-{\mathrm{\Σc}}_{\sup }\left(t\right)\·E_{\mathrm{xsup}}\left(t\right)-C_{\mathrm{eq}}\left(t\right){-C}_m\left(t\right)]\mathrm{dt}$

When industrial boiler operation to the τ time after, the economic benefit that Industrial Boiler obtains within this time period is Y (τ), if industrial boiler operation τ ₀time, Industrial Boiler equipment creates maximum economic benefit, then τ ₀be the Industrial Boiler optimal economic life-span.

5. the detection method of Industrial Boiler thermoeconomic life according to claim 4, it is characterized in that, in step 4, under different load, adopt available egress time positive balance method of testing, determine one group of available egress time value, utilizing least square method to obtain this Industrial Boiler available egress time with the variation relation of thermal load is η _ex=f ₁(X).

6. the detection method of Industrial Boiler thermoeconomic life according to claim 5, is characterized in that, in step 4, these available egress time positive balance method of testing concrete steps of Industrial Boiler comprise:

A () uses the sampling method thief coal of traditional Industrial Boiler;

B () uses the coal sample preparation method of traditional Industrial Boiler to prepare coal sample;

(c) metering fuel;

The quantity of steam of (d) metering steam boiler;

E () measures hot-water boiler quantity of circulating water;

F () measures industrial boiler water-supply pressure;

G () measures industrial boiler steam pressure;

H () measures feed temperature and the outlet steam temperature of steam boiler;

(i) measure the inflow temperature of hot-water boiler and go out water temperature;

J () measures the air themperature into stokehold;

(k) measures ambient temperature;

L () measures saturated steam wetness;

M () calculates Industrial Boiler positive balance available egress time; And

N () utilizes least square curve fit to determine the variation relation of this Industrial Boiler available egress time with thermal load.

7. the detection method of Industrial Boiler thermoeconomic life according to claim 6, is characterized in that, in step (m), Industrial Boiler input is available can computing formula be:

e _xsup=e _xf+e _xwl+e _xrx+e _xzy

In formula, e _xsupthe available energy of input for Industrial Boiler, unit is kJ/kg; e _xffor the fuel entering stove can use energy, unit is kJ/kg; e _xwlfor heating fuel or external heat can use energy, unit is kJ/kg; e _xrxfor the physical thermal of fuel can use energy, unit is kJ/kg; e _xzythe heat brought into for personal steam can use energy, and unit is kJ/kg;

Steam boiler available egress time positive balance computing formula is:

${\mathrm{\η}}_{\mathrm{ex}}=\frac{H_s-H_w-T_0(S_s-S_w)}{{\mathrm{Be}}_{\mathrm{xsup}}}\×100\%$

In formula, η _exfor the positive balance available egress time of steam boiler, %; H _scan energy be used, kJ/h for steam boiler exports steam;

H _wfor steam boiler feeds water available energy, kJ/h; S _sfor steam boiler exports entropy of evaporation, kJ/ (hK); S _wfor steam boiler feedwater entropy, kJ/ (hK); B is the Fuel Consumption of steam boiler, kg/h; T ₀for environment temperature, K;

Hot-water boiler available egress time positive balance computing formula is:

${\mathrm{\η}}_{\mathrm{ex}}=\frac{H_{w2}-H_{w1}-T_0(S_{w2}-S_{w1})}{{\mathrm{Be}}_{\mathrm{xsup}}}$

In formula, H _w1for hot-water boiler feeds water available energy, kJ/h; H _w2for hot-water boiler water outlet can use energy, kJ/h; S _w1for hot-water boiler feedwater entropy, kJ/ (hK); S _w2for hot-water boiler water outlet entropy, kJ/ (hK).

8. the detection method of Industrial Boiler thermoeconomic life according to claim 5, is characterized in that, in steps of 5, utilizes the historical statistical data of industrial boiler operation, and going out that this Industrial Boiler thermal load closes over time with least square fitting is X=f ₂(t).

9. the detection method of Industrial Boiler thermoeconomic life according to claim 8, it is characterized in that, in step 6, utilize historical statistics or the test data of industrial boiler operation, determining that this Industrial Boiler available egress time closes over time by semilog data processing and simple linear regression analysis is η _ex=f ₃(t).

10. the detection method of Industrial Boiler thermoeconomic life according to claim 9, is characterized in that, in step 7, determines that the relational expression that solves of the thermoeconomic life of this Industrial Boiler is:

$Y\left(t\right)=\∫_0^t[{\mathrm{\Σc}}_{\mathrm{out}}\left(t\right)\·f_4(X,{\mathrm{\η}}_{\mathrm{ex}})-{\mathrm{\Σc}}_{\sup }\left(t\right)\·f_5(X,{\mathrm{\η}}_{\mathrm{ex}})-C_{\mathrm{eq}}\left(t\right)-C_m\left(t\right)]\mathrm{dt};$

Trial and error procedure is adopted to solve the thermoeconomic life of this Industrial Boiler.