Method for evaluating performance of supercritical carbon dioxide gas boiler

Abstract

The application discloses a supercritical carbon dioxide gas boiler performance evaluation method, and belongs to the technical field of energy utilization. The application solves the problem that the fuel consumption measurement accuracy cannot be ensured in the prior art, thereby increasing the uncertainty of fuel efficiency calculation. In addition to testing the boiler fuel efficiency, the application also evaluates the heat exchange performance of the supercritical carbon dioxide boiler. In addition to the analysis and research on the heat exchange capacity and proportion of each heat exchange surface, the cold end temperature difference characteristic coefficient of the heat exchange surface is introduced to represent the heat exchange performance of the working medium side, thereby improving the performance evaluation method of the supercritical carbon dioxide boiler. The supercritical carbon dioxide gas boiler performance evaluation method is used for the actual operation monitoring, operation performance analysis and boiler performance evaluation of the supercritical carbon dioxide gas boiler of the first supercritical carbon dioxide power generation cycle.

Description

Technical Field

[0001] This application relates to a novel method for testing the performance of large boilers using a new working fluid, and more particularly to a method for evaluating the performance of supercritical carbon dioxide gas-fired boilers, belonging to the field of energy utilization technology. Background Technology

[0002] Supercritical carbon dioxide cycle technology is an advanced new power generation technology. When applied to fossil fuel power generation, the supercritical carbon dioxide boiler is the core equipment of this technology. The world's first supercritical carbon dioxide boiler was manufactured by Harbin Boiler Factory and used in the 5MWe supercritical carbon dioxide cycle power generation unit at Xi'an Thermal Power Research Institute. Supercritical carbon dioxide cycle power generation technology has advantages such as high efficiency, system simplicity, and compact equipment. Under the same working fluid parameters, supercritical carbon dioxide boilers have higher efficiency and a simpler boiler structure than conventional steam-water boilers.

[0003] However, the development time of supercritical carbon dioxide boiler technology is relatively short, and its quality evaluation system is lacking both domestically and internationally. Therefore, targeted research on power plant boiler performance evaluation technology is of great guiding significance for the development of supercritical carbon dioxide boilers. In my country, research and application of power plant boiler performance evaluation typically refer to GB / T 10184-2015 "Performance Test Procedure for Power Plant Boilers"; however, for new supercritical carbon dioxide boilers, due to differences in circulating working fluid, boiler layout, and operating methods, directly applying GB / T 10184-2015 cannot meet the needs of fuel efficiency testing and performance evaluation.

[0004] The first supercritical carbon dioxide gas-fired boiler is equipped with a separate overheat protection circulating cooling system, the impact of which on boiler fuel efficiency needs to be considered in conjunction with fuel consumption. Due to the common limitation of gas metering instruments exhibiting measurement deviations over large flow ranges, the accuracy of fuel consumption measurement for supercritical carbon dioxide boilers is difficult to guarantee, leading to increased uncertainty in fuel efficiency calculations. Furthermore, due to the unique economizer arrangement of the first supercritical carbon dioxide boiler, a redesigned correction method is required when correcting for deviations in the feed gas (i.e., carbon dioxide medium) temperature at the economizer inlet from the design value. Summary of the Invention

[0005] In view of this, this application provides a performance evaluation method for supercritical carbon dioxide gas-fired boilers to solve the problem in the prior art where the accuracy of fuel consumption measurement is difficult to guarantee, leading to increased uncertainty in fuel efficiency calculation.

[0006] The technical solution of this application is implemented as follows:

[0007] Performance evaluation methods for supercritical carbon dioxide gas-fired boilers include:

[0008] S1. Establish a dynamic storage database to calculate the heat loss from flue gas (Q2), heat loss from incomplete combustion of gas (Q3), heat loss from heat dissipation (Q5), and external heat (Q). ex Other heat losses Q oth Input heat Q in And the effective heat output Q of the boiler system out ;

[0009] Among them, the heat loss Q5 obtained from heat dissipation and other heat losses Q oth The specific steps are as follows:

[0010] S16-1, Based on the heat loss from flue gas Q2, the heat loss from incomplete combustion of gas Q3, and the external heat Q... ex Input heat Q in To obtain the initial boiler fuel efficiency η0:

[0011]

[0012] S16-2, Based on the input heat Q in Effective heat output Q of the boiler system out And the initial boiler fuel efficiency η0, to obtain the fuel consumption q m.f :

[0013]

[0014] S16-3, Based on fuel consumption q m.f and the collected mass flow rate q of cooling water entering the boiler system boundary m.cw To obtain the initial other heat losses Q oth.0 :

[0015]

[0016] Among them, H cw.lv The enthalpy of the cooling water at the outlet of the cooling equipment, and H cw.lv The collected cooling water temperature t at the outlet of the cooling equipment cw.lv and cooling water pressure at the outlet of the cooling equipment p cw.lv Find the enthalpy values ​​of water and water vapor in the table; H cw.en The enthalpy of the cooling water at the inlet of the cooling equipment, and H cw.en The collected cooling water temperature t at the inlet of the cooling equipment cw.en and cooling water pressure at the inlet of the cooling equipment p cw.en Find the enthalpy values ​​of water and water vapor in the table;

[0017] S16-4. Utilizing the collected ambient temperature t near the boiler body a3 The surface temperature T of the outer wall of the i-th mesh wiTo obtain the heat transfer coefficient α of the i-th mesh method. i :

[0018]

[0019] Where i = 1, 2, 3...n, n is the upper limit of the number of grids in the mesh method; ε is the surface thermal emissivity, a fixed value of 0.8; σ is the radiation constant, a fixed value of 5.670373 × 10⁻⁶. -8 W·m -2 ·K -4 ;

[0020] S16-5, Utilizing the collected ambient temperature t near the boiler body a3 The surface temperature T of the outer wall of the i-th mesh wi And the heat transfer coefficient α of the i-th mesh obtained in step S16-4. i Obtain the heat flux density q of the i-th mesh. i :

[0021] q i =α i ×(T wi -t a3 -273.15) (Formula 42);

[0022] S16-6, Using the collected i-th grid method, the grid area A is... i and fuel consumption q m.f Heat flux density q i Obtain the initial heat loss Q 5,0 :

[0023]

[0024] S16-7, Based on the heat loss from flue gas Q2, the heat loss from incomplete combustion of gas Q3, and the external heat Q... ex Input heat Q in Initial other heat losses Q oth,0 and initial heat loss Q 5,0 To obtain the iterative boiler fuel efficiency η 0.dd :

[0025]

[0026] S16-8, Utilizing iterative boiler fuel efficiency η 0.dd The initial boiler fuel efficiency η0 in formula 39 is replaced to complete the calculation of fuel consumption q. m.f Updates and fixes;

[0027] S16-9, Determine the fuel consumption q between two consecutive updates before and after the update.m.f If the absolute value of the difference is less than 0.01%, proceed to step S16-10 if the result is no; otherwise, proceed to step S16-11.

[0028] S16-10, Update fuel consumption q m.f Substitute formulas 40 and 43, and repeat steps S16-7 and S16-8 in sequence to obtain the updated fuel consumption q. m.f Proceed to step S16-9;

[0029] S16-11, Update fuel consumption q m.f Substituting into Equations 40 and 43, we obtain the corrected other heat losses Q. oth Heat loss due to heat dissipation Q5;

[0030] S2, based on the heat loss from exhaust Q2, the heat loss from incomplete combustion Q3, the heat loss from heat dissipation Q5, and the external heat Q... ex Other heat losses Q oth and input heat Q in Find the boiler fuel efficiency η′:

[0031]

[0032] S3, calculate the corrected boiler fuel efficiency η′ xz Specifically, this refers to the measured flue gas temperature t. ds Make corrections to obtain the corrected flue gas temperature t. fg.AH.lv.cr.fw Using the corrected flue gas temperature t fg.AH.lv.cr.fw Replaces flue gas temperature t ds Design value t of inlet air temperature for air preheater a.AH.en.d Instead of measuring the air preheater inlet air temperature t a1 Replace the measured boiler fuel composition data with the boiler design fuel composition data, and repeat steps S1 and S2 to obtain the corrected boiler fuel efficiency η′. xz ;

[0033] S4. Calculate the heat absorption Q of the economizer on the superheater side. SH-Eco The reheater side economizer heat absorption Q RH-Eco The heat absorbed by the air-cooled wall, Q GWC The superheater absorbs heat Q SH The heat absorbed by the reheater, Q RH And the heat absorption Q of the cooling water system Cooling Finally, the total heat absorption of the boiler, Q, is obtained. sum And the proportion of heat exchanged on each heat exchange surface;

[0034] S5. Calculate the temperature difference characteristic coefficient η at the cold end of the economizer on the superheater side.SH-Eco η, the characteristic coefficient of the cold end temperature difference of the economizer on the reheater side RH-Eco η, the characteristic coefficient of cold end temperature difference of air-cooled wall GCW η, the characteristic coefficient of the cold end temperature difference of the superheater SH The reheater cold end temperature difference characteristic coefficient η RH The cold-end temperature difference characteristic coefficient is used to reflect the proportion of residual heat after heat transfer in the heat exchanger. The lower the value, the better the overall heat transfer performance of the heat exchanger.

[0035] In the above technical solution, the specific steps of S3 are as follows:

[0036] S3-1, Using the design value t of the air preheater inlet air temperature a.AH.en.d The measured flue gas temperature at the inlet of the air preheater was collected. fg.AH.en.m Measured flue gas temperature at the outlet of the air preheater (t) fg.AH.lv.m The measured inlet air temperature t of the air preheater a1 The flue gas temperature t is obtained by converting it to the inlet air temperature of the designed air preheater. fg.AH.lv.cr.a :

[0037]

[0038] S3-2. Calculate the flue gas temperature t based on the converted air temperature at the inlet air temperature of the air preheater obtained in step S3-1. fg.AH.lv.cr.a And the collected economizer flue gas inlet temperature t on the superheater side. SH-Eco.gas.in Superheater side economizer flue gas outlet temperature t fg.Eco.lv.SH Measured economizer feed gas temperature t Eco.in Measured flue gas temperature at the inlet of the air preheater (t) fg.AH.en.m Economizer feed gas temperature design value t fw.Eco.d Design value of air preheater inlet air temperature t a.AH.en.d The flue gas temperature t is obtained from the superheater side and converted to the design air preheater inlet air temperature. fg.AH.lv.cr.fw.SH :

[0039]

[0040] S3-3, Calculate the flue gas temperature t based on the converted air temperature at the inlet air temperature of the air preheater obtained in step S3-1. fg.AH.lv.cr.a And the collected reheater side economizer flue gas inlet temperature t RH-Eco.gas.in The reheater side economizer flue gas outlet temperature t fg.Eco.lv.RH Measured economizer feed gas temperature t Eco.in Measured flue gas temperature at the inlet of the air preheater (t) fg.AH.en.m The reheater side economizer flue gas outlet temperature t fg.Eco.lv.RH Design economizer feed gas temperature tfw.Eco.d Design value of air preheater inlet air temperature t a.AH.en.d The flue gas temperature t is obtained from the reheater side and converted to the design air preheater inlet air temperature. fg.AH.lv.cr.fw.RH :

[0041]

[0042] S3-4. Utilize the collected economizer working fluid mass flow rate D on the superheater side. SH-Eco.in Reheater side economizer working fluid mass flow rate D RH-Eco.in The flue gas temperature t of the S3-2 superheater side is converted to the designed air preheater inlet air temperature. fg.AH.lv.cr.fw.SH The flue gas temperature t of the S3-3 reheater side is converted to the designed air preheater inlet air temperature. fg.AH.lv.cr.fw.RH The correction t for the total feed gas temperature on the flue gas temperature is obtained. fg.AH.lv.cr.fw :

[0043]

[0044] S3-5, using the corrected flue gas temperature t fg.AH.lv.cr.fw Replaces flue gas temperature t ds Design value t of inlet air temperature for air preheater a.AH.en.d Instead of measuring the air preheater inlet air temperature t a1 Replace the measured boiler fuel composition data with the boiler design fuel composition data, and repeat steps S1 and S2 to obtain the corrected boiler fuel efficiency η′. xz .

[0045] Further: The specific steps in S3-5 are as follows: using the corrected flue gas temperature t obtained in step S3-4 fg.AH.lv.cr.fw Replaces the collected flue gas temperature t ds Design value t of inlet air temperature for air preheater a.AH.en.d (°C) replaces the collected air preheater inlet air temperature t a1 (°C), Design value of CO concentration in gaseous fuel C CO.fuel.d The concentration C of CO in the gaseous fuel that was replaced CO.fuel The design value C for the concentration of H2 in gaseous fuel. H2.fuel.d The concentration C of H2 in the gaseous fuel that was replaced by the collected fuel H2.fuel The design value C for the concentration of H2S in gaseous fuel. H2S.fuel.d The concentration C of H2S in the alternative gaseous fuel was used for sampling. H2S.fuel The design value C for the concentration of CH4 in gaseous fuel. CH4.fuel.d The concentration C of CH4 in the alternative gaseous fuel collected CH4.fuel The design value C2H6 concentration in the gaseous fuel.C2H6.fuel.d The concentration C2H6 in the alternative gaseous fuel is C C2H6.fuel The design value of C3H8 concentration in gaseous fuel C C3H8.fuel.d The concentration C3H8 in the gaseous fuel that was replaced by the collected gaseous fuel C3H8.fuel Using gaseous fuels containing C4H 10 Concentration design value C C4H10.fuel.d Replace the collected gaseous fuel C4H 10 Concentration C C4H10.fuel C5H in gaseous fuel 12 Concentration design value C C5H12.fuel.d Replace the collected gaseous fuel C5H 12 Concentration C C5H12.fuel The design value of C2H4 concentration in gaseous fuel C C2H4.fuel.d The concentration C2H4 in the alternative gaseous fuel is C C2H4.fuel The design value of C3H6 concentration in gaseous fuel C C3H6.fuel.d The concentration C3H6 in the gaseous fuel that was replaced by the collected gaseous fuel C3H6.fuel The design value of C4H8 concentration in gaseous fuel C C4H8.fuel.d The concentration C4H8 in the alternative gaseous fuel is C C4H8.fuel The design value C for the O2 concentration in gaseous fuel. O2.fuel.d The concentration C of O2 in the alternative gaseous fuel collected O2.fuel The design value C for the CO2 concentration in gaseous fuels. CO2.fuel.d The concentration C of CO2 in the alternative gaseous fuel collected CO2.fuel The design value C for the N2 concentration in gaseous fuel. N2.fuel.d The concentration C of N2 in the gaseous fuel used for replacement N2.fuel Humidity design value h for gaseous fuels g.d Humidity h of the gaseous fuel used for replacement g Repeat steps S1 and S2 to obtain the corrected boiler fuel efficiency η′. xz .

[0046] In the above technical solution, the specific steps of S4 are as follows:

[0047] S4-1, Obtaining heat absorption from the air-cooled wall

[0048] Using the collected main feed gas mass flow rate D GWC.in Main feed gas temperature t GWC.in Main air supply pressure p GWC.in t of working fluid at the outlet of the air-cooled wall GWC.out The working fluid pressure at the outlet of the air-cooled wall, p GWC.out Q is obtained by absorbing heat from the air-cooled wall. GWC :

[0049] QGWC =D GWC.in (H GWC.out -H GWC.in ) (Formula 49);

[0050] Among them, H GWC.in The enthalpy of the working fluid at the inlet of the air-cooled wall, and H GWC.in The main feed gas temperature t was collected. GWC.in and main supply air pressure p GWC.in Find the enthalpy of carbon dioxide in the table; H GWC.out The enthalpy of the working fluid at the outlet of the air-cooled wall, and H GWC.out The working fluid temperature t at the outlet of the air-cooled wall was collected. GWC.out and the working fluid pressure p at the outlet of the air-cooled wall GWC.out Find the enthalpy of carbon dioxide in the table.

[0051] S4-2, Obtaining heat absorption from the superheater

[0052] Using the collected superheater working fluid mass flow rate D SH.out Superheater working fluid outlet temperature t SH.out Superheater working fluid outlet pressure p SH.out Superheater working fluid inlet temperature t SH.in Superheater working fluid inlet pressure p SH.in To obtain the heat absorbed by the superheater, Q SH :

[0053] Q SH =D SH.out (H SH.out -H SH.in ) (Formula 50);

[0054] Among them, H SH.out The enthalpy of the working fluid at the superheater outlet, and H SH.out The superheater working fluid outlet temperature t was collected. SH.out and the superheater working fluid outlet pressure p SH.out Find the enthalpy of carbon dioxide in the table; H SH.in The enthalpy of the working fluid at the superheater inlet, and H SH.in The superheater working fluid inlet temperature t was collected. SH.in and superheater working fluid inlet pressure p SH.in Find the enthalpy of carbon dioxide in the table.

[0055] S4-3, Obtain heat absorption from the reheater

[0056] Using the collected reheater working fluid mass flow rate D RH.out Reheater working fluid outlet temperature t RH.out Reheater working fluid outlet pressure p RH.out Reheater working fluid inlet temperature tRH.in Reheater working fluid inlet pressure p RH.in To obtain the heat absorbed by the reheater, Q RH :

[0057] Q RH =D RH.out (H RH.out -H RH.in ) (Formula 51);

[0058] Among them, H RH.out The enthalpy of the working fluid at the reheater outlet, and H RH.out The reheater working fluid outlet temperature t was collected. RH.out and reheater working fluid outlet pressure p RH.out Find the enthalpy of carbon dioxide in the table; H RH.in The enthalpy of the working fluid at the reheater inlet, and H RH.in The reheater working fluid inlet temperature t was collected. RH.in and reheater working fluid inlet pressure p RH.in Find the enthalpy of carbon dioxide in the table.

[0059] S4-4, Obtaining the heat absorption of the economizer on the superheater side.

[0060] Utilizing the collected economizer working fluid mass flow rate D on the superheater side SH-Eco.in superheater side economizer working fluid inlet temperature t SH-Eco.SCO2.in Superheater side economizer working fluid inlet pressure p SH-Eco.SCO2.in Superheater side economizer working fluid outlet temperature t SH-Eco.SCO2.out Superheater side economizer working fluid outlet pressure p SH-Eco.SCO2.out To obtain the heat absorption Q of the economizer on the superheater side SH -Eco:

[0061] Q SH-Eco =D SH-Eco.in (H SH-Eco.out -H SH-Eco.in ) (Formula 52);

[0062] Wherein, HSH-Eco.out is the enthalpy of the working fluid at the economizer outlet on the superheater side, and H SH-Eco.out The collected economizer working fluid outlet temperature t on the superheater side SH-Eco.SCO2.out and the working fluid outlet pressure p of the economizer on the superheater side SH-Eco.SCO2.out Find the enthalpy of carbon dioxide in the table; H SH-Eco.in The enthalpy of the working fluid at the economizer inlet on the superheater side, and H SH-Eco.in The collected economizer working fluid inlet temperature t on the superheater side SH-Eco.SCO2.in and the working fluid inlet pressure p of the economizer on the superheater side SH-Eco.SCO2.in Find the enthalpy of carbon dioxide in the table.

[0063] S4-5, Obtain the heat absorption of the economizer on the reheater side.

[0064] Utilizing the collected reheater-side economizer working fluid mass flow rate D RH-Eco.in Economizer working fluid inlet temperature t on the reheater side RH-Eco.SCO2.in The reheater side economizer working fluid inlet pressure p RH-Eco.SCO2.in Economizer working fluid outlet temperature t on the reheater side RH-Eco.SCO2.out The reheater side economizer working fluid outlet pressure p RH-Eco.SCO2.out To obtain the heat absorption Q of the economizer on the reheater side RH-Eco :

[0065] Q RH-Eco =D RH-Eco.in (H RH-Eco.out -H RH-Eco.in ) (Formula 53);

[0066] Among them, H RH-Eco.out The enthalpy of the working fluid at the economizer outlet on the reheater side, and H RH-Eco.out The reheater side economizer working fluid outlet temperature t was collected. RH-Eco.SCO2.out and the reheater side economizer working fluid outlet pressure p RH-Eco.SCO2.out Find the enthalpy of carbon dioxide in the table; H RH-Eco.in The enthalpy of the working fluid at the economizer inlet on the reheater side, and H RH-Eco.in The reheater side economizer working fluid inlet temperature t was collected. RH-Eco.SCO2.in and the reheater side economizer working fluid inlet pressure p RH-Eco.SCO2.in Find the enthalpy of carbon dioxide in the table.

[0067] S4-6, Obtaining heat absorption from the cooling water system

[0068] Using the collected mass flow rate q of cooling water entering the boiler system boundary m.cw Cooling water temperature at the outlet of the cooling equipment (t) cw.lv Cooling water pressure at the outlet of the cooling equipment p cw.lv Cooling water temperature at the inlet of the cooling equipment (t) cw.en Cooling water pressure at the inlet of the cooling equipment p cw.en To obtain the heat absorption Q of the cooling water system Cooling :

[0069] Q Cooling =q m.cw (H cw.lv -H cw.in ) (Formula 54);

[0070] Among them, H cw.in The enthalpy of the working fluid at the inlet of the cooling equipment, and H cw.inThe collected cooling water temperature t at the inlet of the cooling equipment cw.en and cooling water pressure at the inlet of the cooling equipment p cw.en Find the enthalpy values ​​of water and water vapor in the table; H cw.lv The enthalpy of the working fluid at the outlet of the cooling equipment, and H cw.lv The collected cooling water temperature t at the outlet of the cooling equipment cw.lv and cooling water pressure at the outlet of the cooling equipment p cw.lv Find the enthalpy values ​​of water and water vapor in the table;

[0071] S4-7. Obtain the total heat absorption of the boiler.

[0072] The heat absorption Q of the air-cooled wall calculated in step S4-1 GWC The heat absorption Q of the superheater calculated in step S4-2 SH The heat absorption Q of the reheater calculated in step S4-3 RH The heat absorption Q of the economizer on the superheater side is calculated in step S4-4. SH-Eco The heat absorption Q of the economizer on the reheater side is calculated in steps S4-5. RH-Eco The heat absorption Q of the cooling water system calculated in step S4-6 Cooling To obtain the total heat absorption Q of the boiler sum :

[0073] Q sum =Q SH-Eco +Q RH-Eco +Q GCW +Q SH +Q RH +Q Cooling (Formula 55);

[0074] S4-8. Using the heat absorption Q of the air-cooled wall calculated in step S4-1 GWC The total heat absorption Q of the boiler calculated in step S4-7 sum To obtain the heat exchange ratio α of the air-cooled wall GCW :

[0075]

[0076] S4-9. Using the heat absorption Q of the superheater calculated in step S4-2 SH The total heat absorption Q of the boiler calculated in step S4-7 sum To obtain the proportion of heat exchanged by the superheater, α SH :

[0077]

[0078] S4-10. Using the heat absorption Q of the reheater calculated in step S4-3 RHThe total heat absorption Q of the boiler calculated in step S4-7 sum The proportion of reheater heat exchange α is obtained. RH :

[0079]

[0080] S4-11. Calculate the heat absorption Q of the economizer on the superheater side using the method in step S4-4. SH-Eco The total heat absorption Q of the boiler calculated in step S4-7 sum The proportion of heat exchanged by the economizer on the superheater side, α SH-Eco :

[0081]

[0082] S4-12. The heat absorption Q of the economizer on the reheater side calculated in step S4-5. RH-Eco The total heat absorption Q of the boiler calculated in step S4-7 sum To obtain the proportion of reheater-side economizer heat exchange α RH-Eco :

[0083]

[0084] S4-13. Using the heat absorption Q of the cooling water system calculated in step S4-6 Cooling The total heat absorption Q of the boiler calculated in step S4-7 sum The proportion of heat removed by the circulating cooling water, α Cooling :

[0085]

[0086] In the above technical solution, the specific steps of S5 are as follows:

[0087] Using the collected economizer working fluid inlet temperature t on the superheater side SH-Eco.SCO2.in Superheater side economizer working fluid outlet temperature t SH-Eco.SCO2.out Superheater side economizer flue gas inlet temperature t SH-Eco.gas.in The reheater side economizer working fluid inlet temperature t RH-Eco.SCO2.in The reheater side economizer working fluid outlet temperature t RH-Eco.SCO2.out The reheater side economizer flue gas inlet temperature t RH-Eco.gas.in Main feed gas temperature t GWC.in The working fluid temperature at the outlet of the air-cooled wall is t GWC.out air-cooled wall flue gas inlet temperature t GWC.gas.in Superheater working fluid outlet temperature t SH.out Superheater working fluid inlet temperature t SH.in Superheater flue gas inlet temperature t SH.gas.in Reheater working fluid outlet temperature t RH.outReheater working fluid inlet temperature t RH.in Reheater flue gas inlet temperature t RH.gas.in Calculate the characteristic coefficient η of the temperature difference at the cold end of the economizer on the superheater side. SH-Eco η, the characteristic coefficient of the cold end temperature difference of the economizer on the reheater side RH-Eco η, the characteristic coefficient of cold end temperature difference of air-cooled wall GCW η, the characteristic coefficient of the cold end temperature difference of the superheater SH The reheater cold end temperature difference characteristic coefficient η RH The details are as follows:

[0088]

[0089]

[0090]

[0091]

[0092]

[0093] The beneficial effects of this application are reflected in:

[0094] Compared to existing technologies, this application, in addition to testing boiler fuel efficiency, also evaluates the heat exchange performance of supercritical carbon dioxide boilers. Besides the conventional analysis and research on the heat exchange capacity and proportion of each heat exchange surface, it introduces a temperature difference characteristic coefficient at the cold end of the heat exchange surface to characterize the heat exchange performance on the working fluid side, thus improving the performance evaluation method for supercritical carbon dioxide boilers. The performance evaluation method for supercritical carbon dioxide gas-fired boilers proposed in this application is used for the actual operation monitoring, operation performance analysis, and boiler performance evaluation of the world's first supercritical carbon dioxide power generation cycle supercritical carbon dioxide gas-fired boiler. Attached Figure Description

[0095] Other features, objects, and advantages of this application will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0096] Figure 1 This is a flowchart illustrating the calculation of boiler fuel consumption according to an embodiment of this application;

[0097] Figure 2 This is the program architecture diagram of the supercritical carbon dioxide gas-fired boiler performance evaluation method of this application;

[0098] Figure 3 This is a sample diagram of the program interface for the performance evaluation method of supercritical carbon dioxide gas-fired boilers in this application. Detailed Implementation

[0099] The present application will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the relevant application and not intended to limit the application. Furthermore, it should be noted that, for ease of description, only the parts relevant to the application are shown in the accompanying drawings.

[0100] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0101] Specific Implementation Method 1: This application provides a performance evaluation method for supercritical carbon dioxide gas-fired boilers, which comprehensively considers the optimization calculation of fuel consumption and the correction of the feed gas temperature at the economizer inlet deviating from the design value to calculate the fuel efficiency of supercritical carbon dioxide gas-fired boilers, as well as an evaluation method for the performance of the heat exchange surface of supercritical carbon dioxide boilers, specifically including:

[0102] S1 integrates unit DCS data, online flue gas measurement data, fuel monitoring data, boiler heat dissipation monitoring data, environmental parameter measurement data, and boiler design parameters to establish a dynamic storage database, and calculates the heat loss from flue gas Q2, heat loss from incomplete combustion Q3, heat dissipation loss Q5, and external heat Q. ex Other heat losses Q oth Input heat Q in And the effective heat output Q of the boiler system out The dynamic storage database includes: unit DCS data, online flue gas measurement data, fuel monitoring data, boiler heat dissipation monitoring data, environmental parameter measurement data, and boiler design parameters; more specifically: unit DCS data includes D GWC.in D RH-Eco.in D RH.out D SH-Eco.in D SH.out q m.cw t cw.en t cw.lv t Eco.in t fg.AH.en.m t fg.AH.lv.m t fg.Eco.lv.RH t fg.Eco.lv.SH t GWC.gas.in t GWC.in t GWC.out t RH-Eco.gas.in t RH-Eco.SCO2.in t RH-Eco.SCO2.out t RH.gas.in t RH.in t RH.out t SH-Eco.gas.in t SH-Eco.SCO2.in t SH-Eco.SCO2.out t SH.gas.int SH.in t SH.out p cw.en p cw.lv p GWC.in p GWC.out p RH-Eco.SCO2.in p RH-Eco.SCO2.out p RH.in p RH.out p SH-Eco.SCO2.in p SH-Eco.SCO2.out p SH.in p SH.out Online flue gas measurement data includes t ds C O2 C CO2 and C CO Fuel monitoring data includes C CO.fuel C H2.fuel C H2S.fuel C CH4.fuel C C2H6.fuel C C3H8.fuel C C4H10.fuel C C5H12.fuel C C2H4.fuel C C3H6.fuel C C4H8.fuel C O2.fuel C CO2.fuel C N2.fuel h g Heat dissipation monitoring data includes T wi (i = 1, 2, 3 ... n), A i (i = 1, 2, 3...n). Environmental parameter measurement data includes t a1 t a3 p at h a.re Boiler design parameters include t a.AH.en.d t fw.Eco.d C CO.fuel.0 C H2.fuel.0 C H2S.fuel.0 C CH4.fuel.0 C C2H6.fuel.0 C C3H8.fuel.0 C C4H10.fuel.0 C C5H12.fuel.0 C C2H4.fuel.0 C C3H6.fuel.0 C C4H8.fuel.0 C O2.fuel.0 C CO2.fuel.0 C N2.fuel.0 h g.d .

[0103] Among them, D GWC.in Main feed gas mass flow rate (kg / h), D RH-Eco.inD represents the reheater-side economizer working fluid mass flow rate (kg / h). RH.out D is the reheater working fluid mass flow rate (kg / h). SH-Eco.in D represents the mass flow rate (kg / h) of the working fluid in the economizer on the superheater side. SH.out q represents the mass flow rate of the superheater working fluid (kg / h). m.cw The mass flow rate (kg / h) of cooling water entering the boiler system boundary, t cw.en The inlet cooling water temperature of the cooling equipment (°C), t cw.lv The outlet cooling water temperature (°C) of the cooling equipment, t Eco.in To measure the economizer feed gas temperature (°C), t fg.AH.en.m To measure the inlet flue gas temperature (°C) of the air preheater, t fg.AH.lv.m To measure the flue gas temperature (°C) at the outlet of the air preheater, t fg.Eco.lv.RH The reheater side economizer flue gas outlet temperature (°C), t fg.Eco.lv.SH The flue gas outlet temperature (°C) of the economizer on the superheater side is given by t. GWC.gas.in t represents the flue gas inlet temperature (°C) of the air-cooled wall. GWC.in Main feed gas temperature (°C), t GWC.out The outlet working fluid temperature of the air-cooled wall is (°C), t RH-Eco.gas.in The reheater side economizer flue gas inlet temperature (°C), t RH-Eco.SCO2.in The reheater-side economizer working fluid inlet temperature (°C), t RH-Eco.SCO2.out The reheater-side economizer working fluid outlet temperature (°C), t RH.gas.in The reheater flue gas inlet temperature (°C) is t. RH.in The reheater working fluid inlet temperature (°C), t RH.out The reheater working fluid outlet temperature (°C), t SH-Eco.gas.in The inlet temperature of the economizer flue gas on the superheater side is (°C), t SH-Eco.SCO2.in The inlet temperature of the working fluid in the economizer on the superheater side is (°C), t SH-Eco.SCO2.out The economizer working fluid outlet temperature (°C) on the superheater side is given by t. SH.gas.in The superheater flue gas inlet temperature (°C), t SH.in The superheater working fluid inlet temperature (°C), t SH.out p is the outlet temperature of the superheater working fluid (°C). cw.en The inlet cooling water pressure of the cooling equipment (MPa), p cw.lv p is the outlet cooling water pressure (MPa) of the cooling equipment. GWC.in Main supply air pressure (MPa), p GWC.out p is the working fluid pressure at the outlet of the air-cooled wall (MPa). RH-Eco.SCO2.in p is the inlet pressure of the working fluid in the economizer on the reheater side (MPa). RH-Eco.SCO2.out p is the working fluid outlet pressure (MPa) of the economizer on the reheater side.RH.in p is the inlet pressure of the reheater working fluid (MPa). RH.out p is the outlet pressure of the reheater working fluid (MPa). SH-Eco.SCO2.in p is the inlet pressure of the working fluid in the economizer on the superheater side (MPa). SH-Eco.SCO2.out p is the outlet pressure of the working fluid in the economizer on the superheater side (MPa). SH.in p is the inlet pressure of the superheater working fluid (MPa). SH.out This represents the outlet pressure of the superheater working fluid (MPa). t ds C represents the exhaust gas temperature (°C). O2 The O2 concentration (%) at the dry ground state flue gas exhaust point, C CO2 The CO2 concentration (%) at the dry ground state flue gas exhaust point, C CO CO concentration (%) at the dry ground state flue gas exhaust point. CO.fuel The concentration (%) of CO in gaseous fuel, C H2.fuel The concentration (%) of H2 in gaseous fuel, C H2S.fuel The concentration (%) of H2S in gaseous fuels, C CH4.fuel The concentration (%) of CH4 and C in gaseous fuels C2H6.fuel The concentration (%) of C2H6 in gaseous fuel, C C3H8.fuel The concentration (%) of C3H8 in gaseous fuel, C C4H10.fuel C4H in gaseous fuel 10 Concentration (%), C C5H12.fuel C5H in gaseous fuel 12 Concentration (%), C C2H4.fuel The concentration (%) of C2H4 in gaseous fuel, C C3H6.fuel The concentration (%) of C3H6 in gaseous fuel, C C4H8.fuel The concentration (%) of C4H8 in gaseous fuel, C O2.fuel The concentration (%) of O2 in gaseous fuel, C CO2.fuel The concentration (%) of CO2 in gaseous fuel, C N2.fuel The concentration (%) of N2 in gaseous fuel, h g Humidity of gaseous fuel (kg / m³) 3 ).

[0104] T wi Ai is the surface temperature (K) of the outer wall of the i-th mesh, where i = 1, 2, 3...n, and n is the upper limit of the number of meshes in the meshing method; Ai is the area (m²) of the i-th mesh. 2 ), i = 1, 2, 3...n, where n is the upper limit of the number of grids in the grid method. t a1 The air temperature at the inlet of the air preheater (°C), t a3 The ambient temperature (°C) near the boiler body, p ath is the atmospheric pressure (Pa) near the boiler body. a.re The relative humidity (%) of the air near the boiler body. a.AH.en.d Design value of air inlet temperature (°C), t fw.Eco.d The economizer feed gas temperature design value (°C), C CO.fuel.d The design value (%) of CO concentration in gaseous fuel, C H2.fuel.d The design value (%) of H2 concentration in gaseous fuel, C H2S.fuel.d The design value (%) of H2S concentration in gaseous fuel, C CH4.fuel.d The design values ​​(%) for CH4 concentration in gaseous fuels, C C2H6.fuel.d The design value (%) of C2H6 concentration in gaseous fuel, C C3H8.fuel.d The design value (%) of C3H8 concentration in gaseous fuel, C C4H10.fuel.d C4H in gaseous fuel 10 Concentration design value (%), C C5H12.fuel.d C5H in gaseous fuel 12 Concentration design value (%), C C2H4.fuel.d The design value (%) of C2H4 concentration in gaseous fuel, C C3H6.fuel.d The design value (%) of C3H6 concentration in gaseous fuel, C C4H8.fuel.d The design value (%) of C4H8 concentration in gaseous fuel, C O2.fuel.d The design value (%) of O2 concentration in gaseous fuel, C CO2.fuel.d The design value (%) of CO2 concentration in gaseous fuel, C N2.fuel.d The design value (%) of N2 concentration in gaseous fuel, h g.d Design humidity value for gaseous fuel (kg / m³) 3 ).

[0105] In step S1, the supercritical carbon dioxide gas boiler performance evaluation calculation program calls data from the dynamic storage database to obtain the heat loss from flue gas Q2, the heat loss from incomplete combustion of gas Q3, the heat loss from heat dissipation Q5, and the external heat Q. ex Other heat losses Q oth and input heat Q in The implementation involves the following steps:

[0106] S11, Obtain the heat loss from flue gas Q2.

[0107] S11-1, Based on the CO concentration C in the collected gaseous fuel... CO.fuel The concentration C of H2 in gaseous fuel H2.fuel The concentration C of H2S in gaseous fuel H2S.fuel The concentration C of CH4 in gaseous fuel CH4.fuelThe concentration of C2H6 in gaseous fuels, C C2H6.fuel The concentration of C3H8 in gaseous fuels, C C3H8.fuel C4H in gaseous fuels 10 Concentration C C4H10.fuel C5H in gaseous fuels 12 Concentration C C5H12.fuel The concentration of C2H4 in gaseous fuels, C C2H4.fuel The concentration of C3H6 in gaseous fuels, C C3H6.fuel The concentration of C4H8 in gaseous fuels, C C4H8.fuel The concentration of O2 in gaseous fuels, C O2.fuel The theoretical dry air volume V obtained from gaseous fuel a.d.th.g (m 3 / m 3 );

[0108]

[0109] S11-2, The theoretical dry air quantity V of the gaseous fuel obtained in step S11-1 a.d.th.g And the concentration C of CO2 in the collected gaseous fuel. CO2.fuel The concentration of CO in gaseous fuels, C CO.fuel The concentration C of H2S in gaseous fuel H2S.fuel The concentration C of CH4 in gaseous fuel CH4.fuel The concentration of C2H6 in gaseous fuels, C C2H6.fuel The concentration of C3H8 in gaseous fuels, C C3H8.fuel C4H in gaseous fuels 10 Concentration C C4H10.fuel C5H in gaseous fuels 12 Concentration C C5H12.fuel The concentration of C2H4 in gaseous fuels, C C2H4.fuel The concentration of C3H6 in gaseous fuels, C C3H6.fuel The concentration of C4H8 in gaseous fuels, C C4H8.fuel The concentration C of N2 in gaseous fuel N2.fuel The theoretical dry flue gas volume V obtained from gaseous fuel fg.d.th.g (m 3 / m 3 );

[0110]

[0111] S11-3, Utilizing the collected O2 concentration C at the dry ground state flue gas exhaust point O2 The corrected excess air coefficient α is obtained. cr (dimensionless);

[0112]

[0113] S11-4. The theoretical dry air quantity V of the gaseous fuel obtained in step S11-1. a.d.th.g The theoretical dry flue gas volume V of the gaseous fuel obtained in step S11-2 fg.d.th.g and the corrected excess air coefficient α obtained in step S11-3 cr To obtain the actual dry flue gas volume V fg.d.AH.lv (m 3 / m 3 );

[0114] V fg.d.AH.lv =V fg.d.th.g +(α cr -1)×V a.d.th.g (Formula 5);

[0115] S11-5, Utilizing the collected O2 concentration C at the dry ground state flue gas exhaust point O2 CO2 concentration C at the dry ground state flue gas exhaust point CO2 CO concentration C at the dry ground state flue gas exhaust point CO The N2 concentration C at the dry ground state flue gas exhaust point was obtained. N2 (%)

[0116] C N2 =100-C O2 -C CO2 -C CO (Formula 6);

[0117] S11-6, The actual dry flue gas volume V obtained from step S11-4 fg.d.AH.lv and the collected flue gas temperature t ds The heat Q carried away by the dry flue gas is obtained. 2.fg.d (kJ / m 3 );

[0118] Q 2.fg.d =V fg.d.AH.1v ×c′ p.fg.d ×(t ds -t re ) (Formula 7);

[0119] Among them, t re This is the reference temperature (°C), which is a fixed value of 25°C for specific applications.

[0120] In the formula,

[0121]

[0122] In the formula,

[0123]

[0124]

[0125]

[0126]

[0127] Where, c′ p.fg.d The average isobaric specific heat capacity of dry flue gas from the reference temperature to the exhaust temperature (kJ / (m3·K)); c′ N2 c′ is the average isobaric specific heat capacity of nitrogen from the reference temperature to the flue gas temperature (kJ / (m3·K)); O2 The average isobaric specific heat capacity of oxygen from the reference temperature to the flue gas temperature (kJ / (m3·K)); c′ CO2 c′ is the average isobaric specific heat capacity of carbon dioxide from the reference temperature to the flue gas temperature (kJ / (m3·K)); CO The average isobaric specific heat capacity of carbon monoxide from the reference temperature to the flue gas temperature (kJ / (m3·K));

[0128] The applicable temperature range for formulas 9 to 12 is -18.15 to 726.85℃;

[0129] S11-7, Utilizing the collected ambient temperature t near the boiler body a3 Obtain the water vapor saturation pressure p at ambient temperature. wv.sat (Pa);

[0130]

[0131] The applicable temperature range in the formula is 0~50℃;

[0132] S11-8, The water vapor saturation pressure p at the ambient temperature obtained in step S11-7. wv.sat and the atmospheric pressure p near the boiler body collected. at The relative humidity of the air near the boiler body (h) a.re To obtain the absolute humidity h of the air a.ab (kg / kg);

[0133]

[0134] Among them, the absolute humidity of the air h a.ab It represents the kilogram mass of water vapor in one kilogram of dry air;

[0135] S11-9, The theoretical dry air quantity V of gaseous fuel obtained from S11-1 a.d.th.g The corrected excess air coefficient α obtained in step S11-3 cr The absolute humidity h of the air obtained in step S11-8 a.ab And the concentration C of H2 in the collected gaseous fuel.H2.fuel The concentration C of H2S in gaseous fuel H2S.fuel The concentration C of CH4 in gaseous fuel CH4.fuel The concentration of C2H6 in gaseous fuels, C C2H6.fuel The concentration of C3H8 in gaseous fuels, C C3H8.fuel C4H in gaseous fuels 10 Concentration C C4H10.fuel C5H in gaseous fuels 12 Concentration C C5H12.fuel The concentration of C2H4 in gaseous fuels, C C2H4.fuel The concentration of C3H6 in gaseous fuels, C C3H6.fuel The concentration of C4H8 in gaseous fuels, C C4H8.fuel Humidity h of gaseous fuel g The volume V of water vapor in the flue gas is obtained. wv.fg.AH.lv (m 3 / m 3 );

[0136]

[0137] Where, ρ air The density of dry air under standard conditions (kg / m³) 3 );ρ wv The density of water vapor under standard conditions (kg / m³) 3 );

[0138] In practical applications, ρ air This is an empirical value, 1.293 kg / m³ 3 ;ρ wv This is a fixed value, 0.80357 kg / m³. 3 ;

[0139] S11-10, Based on the volume V of water vapor in the flue gas obtained in step S11-9 wv.fg.AH.lv and the collected flue gas temperature t ds The heat Q carried away by the water vapor in the flue gas is obtained. 2.wv.fg (kJ / m 3 );

[0140] Q 2.wv.fg =V wv.fg.AH.lv ×c′ p.wv ×(t ds -t re ) (Formula 16);

[0141] Among them, t re This is the reference temperature (°C), which is a fixed value of 25°C for specific applications.

[0142] c′ p.wvThe average isobaric specific heat capacity of water vapor from the reference temperature to the flue gas temperature (kJ / (m³)) 3 ·K)), specifically:

[0143]

[0144] The applicable temperature range for this formula is -18.15 to 726.85℃;

[0145] S11-11, The heat Q carried away by the dry flue gas obtained in step S11-6 2.fg.d The heat Q carried away by the water vapor in the flue gas obtained in steps S11-10 2.wv.fg The heat loss from exhaust gas, Q2, is obtained.

[0146] Q2 = Q 2.fg.d +Q 2.wv.fg (Formula 18);

[0147] S12, The actual dry flue gas volume V obtained from step S11-4 fg.d.AH.lv The CO concentration C collected at the dry ground state flue gas exhaust point CO The method for calculating the heat loss Q3 due to incomplete combustion of the gas is as follows:

[0148]

[0149] Among them, Q CO The calorific value of carbon monoxide upon complete combustion (kJ / m³) 3 In specific applications, this is a fixed value: 12636 kJ / m³. 3 ;

[0150] S13, Obtain external heat Q ex .

[0151] S13-1, Utilizing the collected air inlet temperature t of the air preheater a1 And the dry air density ρ under standard conditions air (1.293kg / m 3 ), to obtain the density ρ of the air entering the system boundary. p.a.d (kg / m 3 );

[0152]

[0153] S13-2, Utilizing the collected air inlet temperature t of the air preheater a1 Obtain the instantaneous isobaric specific heat capacity c of the air entering the system boundary. p.a.d (kJ / (m 3 ·K));

[0154]

[0155] The applicable temperature range for this formula is -18.15 to 726.85℃;

[0156] S13-3, Based on the reference temperature t re (25℃), and the density ρ of dry air under standard conditions. air (1.293kg / m 3 ), to obtain the density ρ of air at the reference temperature. p.a.re (kg / m 3 );

[0157]

[0158] S13-4, Based on the reference temperature t re (25℃), obtain the instantaneous isobaric specific heat capacity c of air at the reference temperature. p.a.re (kJ / (m 3 ·K));

[0159]

[0160] The applicable temperature range for this formula is -18.15 to 726.85℃;

[0161] S13-5, The theoretical dry air quantity V of the gaseous fuel obtained in step S11-1 a.d.th.g The corrected excess air coefficient α obtained in step S11-3 cr The density ρ of the air entering the system boundary obtained in step S13-1 p.a.d The instantaneous isobaric specific heat capacity c of the air entering the system boundary obtained in step S13-2 p.a.d The density ρ of air at the reference temperature obtained in step S13-3 p.a.re The instantaneous isobaric specific heat capacity c of air at the reference temperature obtained in step S13-4 p.a.re and the collected air inlet temperature t of the air preheater a1 and reference temperature t re (25℃), the density of dry air under standard conditions ρ air (1.293kg / m 3 The system obtains the heat Q carried by the dry air entering it. a,d (kJ / m 3 );

[0162]

[0163] S13-6, Utilizing the collected air inlet temperature t of the air preheater a1 The instantaneous isobaric specific heat capacity c of the water vapor entering the system boundary is obtained. p.wv(kJ / (m 3 ·K));

[0164]

[0165] The applicable temperature range for this formula is -18.15 to 726.85℃;

[0166] S13-7, The theoretical dry air quantity V of the gaseous fuel obtained in step S11-1 a.d.th.g The corrected excess air coefficient α obtained in step S11-3 cr The absolute humidity h of the air obtained in step S11-8 a.ab The instantaneous isobaric specific heat capacity c of the water vapor entering the system boundary obtained in step S13-6 p.wv and the collected air inlet temperature t of the air preheater a1 and reference temperature t re (25℃), the density of dry air under standard conditions ρ air (1.293kg / m 3 ), water vapor density ρ under standard conditions wv (0.80357kg / m 3 The system obtains the heat Q carried by water vapor in the air entering the system. wv (kJ / m 3 );

[0167]

[0168] S13-8, Based on the N2 concentration C at the dry ground state flue gas exhaust obtained in step S11-5 N2 The collected dry ground state O2 concentration C at the flue gas exhaust point O2 CO2 concentration C at the dry ground state flue gas exhaust point CO2 CO concentration C at the dry ground state flue gas exhaust point CO and reference temperature t re (25℃) Obtain the instantaneous isobaric specific heat capacity c of dry flue gas at the reference temperature. p.fg.re (kJ / (m 3 ·K));

[0169]

[0170] in,

[0171]

[0172]

[0173]

[0174]

[0175] Where, c′ N2.re The instantaneous isobaric specific heat capacity of nitrogen at the reference temperature (kJ / (m3·K)); c′ O2.re The instantaneous isobaric specific heat capacity of oxygen at the reference temperature (kJ / (m3·K)); c′ CO2.re The instantaneous isobaric specific heat capacity of carbon dioxide at the reference temperature (kJ / (m3·K)); c′ CO.re The instantaneous average isobaric specific heat capacity of carbon monoxide at the reference temperature (kJ / (m3·K));

[0176] The applicable temperature range for formulas 28 to 31 is -18.15 to 726.85℃;

[0177] S13-9, Based on the N2 concentration C at the dry ground state flue gas exhaust obtained in step S11-5 N2 The collected dry ground state O2 concentration C at the flue gas exhaust point O2 CO2 concentration C at the dry ground state flue gas exhaust point CO2 CO concentration C at the dry ground state flue gas exhaust point CO Obtain the dry flue gas density ρ under standard conditions. p.fg.d (kg / m 3 );

[0178]

[0179] Where, ρ N2 The density of nitrogen gas under standard conditions (kg / m³) 3 );ρ O2 ρ is the density of oxygen under standard conditions (kg / m3); CO2 ρCO is the density of carbon dioxide under standard conditions (kg / m3); ρCO is the density of carbon monoxide under standard conditions (kg / m3). 3 );

[0180] In practical applications, ρ N2 This is a fixed value, 1.2501 kg / m³. 3 ;ρ O2 This is a fixed value, 1.4278 kg / m³. 3 ;ρ CO2 This is a fixed value, 1.9638 kg / m³. 3 ;ρ CO This is a fixed value, 1.2499 kg / m³. 3 ;

[0181] S13-10, The dry flue gas density ρ under standard conditions obtained according to step S13-9. p.fg.d and reference temperature t re (25℃) Obtain the dry flue gas density ρ at the reference temperature.p.fg.re (kg / m 3 );

[0182]

[0183] S13-11, The theoretical dry air quantity V of the gaseous fuel obtained in step S11-1 a.d.th.g The corrected excess air coefficient α obtained in step S11-3 cr The actual dry flue gas volume V obtained in step S11-4 fg.d.AH.lv The density ρ of air at the reference temperature obtained in step S13-3 p.a.re The instantaneous isobaric specific heat capacity c of air at the reference temperature obtained in step S13-4 p.a.re The instantaneous isobaric specific heat capacity c of dry flue gas at the reference temperature obtained in step S13-8 p.fg.re The dry flue gas density ρ under standard conditions obtained in step S13-9 p.fg.d The dry flue gas density ρ at the reference temperature obtained in step S13-10 p.fg.re and reference temperature t re (25℃) and the density of dry air under standard conditions ρ air (1.293kg / m 3 The corrected heat of conversion Q of dry flue gas and dry air is obtained. XZ.l (kJ / m 3 );

[0184]

[0185] S13-12, The heat Q carried by the dry air entering the system, obtained from step S13-5. a.d The heat Q carried by water vapor in the air entering the system, obtained in step S13-7. WV The corrected heat of conversion Q of dry flue gas and dry air obtained in step S13-11 XZ.l , obtain external heat Q ex ;

[0186] Q ex =Q a.d +Q wv +Q xz.1 (Formula 35);

[0187] S14, Obtain the input heat Q in .

[0188] Using the CO concentration C in the collected gaseous fuel CO.fuel The concentration C of H2 in gaseous fuel H2.fuel The concentration C of H2S in gaseous fuel H2S.fuelThe concentration C of CH4 in gaseous fuel CH4.fuel The concentration of C2H6 in gaseous fuels, C C2H6.fuel The concentration of C3H8 in gaseous fuels, C C3H8.fuel C4H in gaseous fuels 10 Concentration C C4H10.fuel C5H in gaseous fuels 12 Concentration C C5H12.fuel The concentration of C2H4 in gaseous fuels, C C2H4.fuel The concentration of C3H6 in gaseous fuels, C C3H6.fuel The concentration of C4H8 in gaseous fuels, C C4H8.fuel Obtain the input heat Q in Specifically as follows:

[0189]

[0190] S15, Obtain the effective output heat Q of the boiler system out .

[0191] Using the collected superheater working fluid mass flow rate D SH.out Superheater working fluid outlet temperature t SH.out Superheater working fluid outlet pressure p SH.out Reheater working fluid mass flow rate D RH.out Reheater working fluid outlet temperature t RH.out Reheater working fluid outlet pressure p RH.out Main feed gas mass flow rate D GWC.in Main feed gas temperature t GWC.in Main air supply pressure p GWC.in Reheater working fluid inlet temperature t RH.in Reheater working fluid inlet pressure p RH.in Superheater side economizer working fluid mass flow rate D SH-Eco.in superheater side economizer working fluid inlet temperature t SH-Eco.SCO2.in Superheater side economizer working fluid inlet pressure p SH-Eco.SCO2.in Reheater side economizer working fluid mass flow rate D RH-Eco.in Economizer working fluid inlet temperature t on the reheater side RH-Eco.SCO2.in and the reheater side economizer working fluid inlet pressure p RH-Eco.SCO2.in To obtain the effective output heat Q of the boiler system out The details are as follows:

[0192] Q out =D SH.out H SH.out +D RH.out H RH.out -D GWC.in H GWC.in -D RH.out H RH.in-D sH-Eco.in H SH-Eco.in -D RH-Eco.in H RH-Eco.in (Formula 37);

[0193] Among them, H SH.out The enthalpy of the working fluid at the superheater outlet (kJ / kg), and H SH.out The superheater working fluid outlet temperature t was collected. SH.out and the superheater working fluid outlet pressure p SH.out Find the enthalpy of carbon dioxide in the table. RH.out The enthalpy of the working fluid at the reheater outlet (kJ / kg), and H RH.out The reheater working fluid outlet temperature t was collected. RH.out and reheater working fluid outlet pressure p RH.out Find the enthalpy of carbon dioxide in the table. GWC.in The enthalpy of the working fluid at the inlet of the air-cooled wall is (kJ / kg), and H GWC.in The main feed gas temperature t was collected. GWC.in and main supply air pressure p GWC.in Find the enthalpy of carbon dioxide in the table. RH.in The enthalpy of the reheater inlet working fluid is (kJ / kg), and H RH.in The reheater working fluid inlet temperature t was collected. RH.in and reheater working fluid inlet pressure p RH.in Find the enthalpy of carbon dioxide in the table. SH-Eco.in The enthalpy of the working fluid at the economizer inlet on the superheater side (kJ / kg), and H SH-Eco.in The collected economizer working fluid inlet temperature t on the superheater side SH-Eco.SCO2.in and the working fluid inlet pressure p of the economizer on the superheater side SH-Eco.SCO2.in Find the enthalpy of carbon dioxide in the table. RH-Eco.in The enthalpy of the working fluid at the economizer inlet on the reheater side (kJ / kg), and H RH-Eco.in The reheater side economizer working fluid inlet temperature t was collected. RH-Eco.SCO2.in and the reheater side economizer working fluid inlet pressure p RH-Eco.SCO2.in Find the enthalpy of carbon dioxide in the table.

[0194] S16, Obtain heat loss Q5 and other heat losses Q oth .

[0195] S16-1, Based on the heat loss from flue gas Q2, the heat loss from incomplete combustion of gas Q3, and the external heat Q... ex Input heat Q in To obtain the initial boiler fuel efficiency η0:

[0196]

[0197] S16-2, Based on the input heat Q in Effective heat output Q of the boiler system out And the initial boiler fuel efficiency η0, to obtain the fuel consumption q m.f :

[0198]

[0199] S16-3, Based on fuel consumption q m.f and the collected mass flow rate q of cooling water entering the boiler system boundary m.cw To obtain the initial other heat losses Q oth.0 :

[0200]

[0201] Among them, H cw.lv The enthalpy of the cooling water at the outlet of the cooling equipment, and H cw.lv The collected cooling water temperature t at the outlet of the cooling equipment cw.lv and cooling water pressure at the outlet of the cooling equipment p cw.lv Find the enthalpy values ​​of water and water vapor in the table; H cw.en The enthalpy of the cooling water at the inlet of the cooling equipment, and H cw.en The collected cooling water temperature t at the inlet of the cooling equipment cw.en and cooling water pressure at the inlet of the cooling equipment p cw.en Find the enthalpy values ​​of water and water vapor in the table;

[0202] S16-4. Utilizing the collected ambient temperature t near the boiler body a3 The surface temperature T of the outer wall of the i-th mesh wi To obtain the heat transfer coefficient α of the i-th mesh method. i :

[0203]

[0204] Where i = 1, 2, 3...n, n is the upper limit of the number of grids in the mesh method; ε is the surface thermal emissivity, a fixed value of 0.8; σ is the radiation constant, a fixed value of 5.670373 × 10⁻⁶. -8 W·m -2 ·K -4 ;

[0205] S16-5, Utilizing the collected ambient temperature t near the boiler body a3 The surface temperature T of the outer wall of the i-th mesh wi And the heat transfer coefficient α of the i-th mesh obtained in step S16-4. iObtain the heat flux density q of the i-th mesh. i :

[0206] q i =α i ×(T wi -t a3 -273.15) (Formula 42);

[0207] S16-6, Using the collected i-th grid method, the grid area A is... i and fuel consumption q m.f Heat flux density q i Obtain the initial heat loss Q 5,0 :

[0208]

[0209] S16-7, Based on the heat loss from flue gas Q2, the heat loss from incomplete combustion of gas Q3, and the external heat Q... ex Input heat Q in Initial other heat losses Q oth,0 and initial heat loss Q 5,0 To obtain the iterative boiler fuel efficiency η 0.dd :

[0210]

[0211] S16-8, Utilizing iterative boiler fuel efficiency η 0.dd The initial boiler fuel efficiency η0 in formula 39 is replaced to complete the calculation of fuel consumption q. m.f Updates and fixes;

[0212] S16-9, Determine the fuel consumption q between two consecutive updates before and after the update. m.f If the absolute value of the difference is less than 0.01%, proceed to step S16-10 if the result is no; otherwise, proceed to step S16-11.

[0213] S16-10, Update fuel consumption q m.f Substitute formulas 40 and 43, and repeat steps S16-7 and S16-8 in sequence to obtain the updated fuel consumption q. m.f Proceed to step S16-9;

[0214] S16-11, Update fuel consumption q m.f Substituting into Equations 40 and 43, we obtain the corrected other heat losses Q. oth Heat loss due to heat dissipation Q5.

[0215] S2, based on the heat loss from exhaust Q2, the heat loss from incomplete combustion Q3, the heat loss from heat dissipation Q5, and the external heat Q... ex Other heat losses Q oth and input heat Q in Find the boiler fuel efficiency η′:

[0216]

[0217] S3, calculate the corrected boiler fuel efficiency η′ xz Specifically, this refers to the measured flue gas temperature t. ds Make corrections to obtain the corrected flue gas temperature t. fg.AH.lv.cr.fw Using the corrected flue gas temperature t fg.AH.lv.cr.fw Replaces flue gas temperature t ds Design value t of inlet air temperature for air preheater a.AH.en.d Instead of measuring the air preheater inlet air temperature t a1 Replace the measured boiler fuel composition data with the boiler design fuel composition data, and repeat steps S1 and S2 to obtain the corrected boiler fuel efficiency η′. xz .

[0218] Step S3 is as follows:

[0219] S3-1, Using the design value t of the air preheater inlet air temperature a.AH.en.d The measured flue gas temperature at the inlet of the air preheater was collected. fg.AH.en.m Measured flue gas temperature at the outlet of the air preheater (t) fg.AH.lv.m The measured inlet air temperature t of the air preheater a1 The flue gas temperature t is obtained by converting it to the inlet air temperature of the designed air preheater. fg.AH.lv.cr.a :

[0220]

[0221] S3-2. Calculate the flue gas temperature t based on the converted air temperature at the inlet air temperature of the air preheater obtained in step S3-1. fg.AH.lv.cr.a And the collected economizer flue gas inlet temperature t on the superheater side. SH-Eco.gas.in Superheater side economizer flue gas outlet temperature t fg.Eco.lv.SH Measured economizer feed gas temperature t Eco.in Measured flue gas temperature at the inlet of the air preheater (t) fg.AH.en.m Economizer feed gas temperature design value t fw.Eco.d Design value of air preheater inlet air temperature t a.AH.en.d The flue gas temperature t is obtained from the superheater side and converted to the design air preheater inlet air temperature. fg.AH.lv.cr.fw.SH :

[0222]

[0223] S3-3, Calculate the flue gas temperature t based on the converted air temperature at the inlet air temperature of the air preheater obtained in step S3-1. fg.AH.lv.cr.a And the collected reheater side economizer flue gas inlet temperature t RH-Eco.gas.in The reheater side economizer flue gas outlet temperature t fg.Eco.lv.RH Measured economizer feed gas temperature t Eco.in Measured flue gas temperature at the inlet of the air preheater (t) fg.AH.en.m The reheater side economizer flue gas outlet temperature t fg.Eco.lv.RH Design economizer feed gas temperature t fw.Eco.d Design value of air preheater inlet air temperature t a.AH.en.d The flue gas temperature t is obtained from the reheater side and converted to the design air preheater inlet air temperature. fg.AH.lv.cr.fw.RH :

[0224]

[0225] S3-4. Utilize the collected economizer working fluid mass flow rate D on the superheater side. SH-Eco.in Reheater side economizer working fluid mass flow rate D RH-Eco.in The flue gas temperature t of the S3-2 superheater side is converted to the designed air preheater inlet air temperature. fg.AH.lv.cr.fw.SH The flue gas temperature t of the S3-3 reheater side is converted to the designed air preheater inlet air temperature. fg.AH.lv.cr.fw.RH The correction t for the total feed gas temperature on the flue gas temperature is obtained. fg.AH.lv.cr.fw :

[0226]

[0227] S3-5, The corrected flue gas temperature t obtained in step S3-4 fg.AH.lv.cr.fw Replaces the collected flue gas temperature t ds Design value t of inlet air temperature for air preheater a.AH.en.d (°C) replaces the collected air preheater inlet air temperature t a1 (°C), Design value of CO concentration in gaseous fuel C CO.fuel.d The concentration C of CO in the gaseous fuel that was replaced CO.fuel The design value C for the concentration of H2 in gaseous fuel. H2.fuel.d The concentration C of H2 in the gaseous fuel that was replaced by the collected fuel H2.fuel The design value C for the concentration of H2S in gaseous fuel. H2S.fuel.d The concentration C of H2S in the alternative gaseous fuel was used for sampling. H2S.fuel The design value C for the concentration of CH4 in gaseous fuel. CH4.fuel.dThe concentration C of CH4 in the alternative gaseous fuel collected CH4.fuel The design value C2H6 concentration in the gaseous fuel. C2H6.fuel.d The concentration C2H6 in the alternative gaseous fuel is C C2H6.fuel The design value of C3H8 concentration in gaseous fuel C C3H8.fuel.d The concentration C3H8 in the gaseous fuel that was replaced by the collected gaseous fuel C3H8.fuel Using gaseous fuels containing C4H 10 Concentration design value C C4H10.fuel.d Replace the collected gaseous fuel C4H 10 Concentration C C4H10.fuel C5H in gaseous fuel 12 Concentration design value C C5H12.fuel.d Replace the collected gaseous fuel C5H 12 Concentration C C5H12.fuel The design value of C2H4 concentration in gaseous fuel C C2H4.fuel.d The concentration C2H4 in the alternative gaseous fuel is C C2H4.fuel The design value of C3H6 concentration in gaseous fuel C C3H6.fuel.d The concentration C3H6 in the gaseous fuel that was replaced by the collected gaseous fuel C3H6.fuel The design value of C4H8 concentration in gaseous fuel C C4H8.fuel.d The concentration C4H8 in the alternative gaseous fuel is C C4H8.fuel The design value C for the O2 concentration in gaseous fuel. O2.fuel.d The concentration C of O2 in the alternative gaseous fuel collected O2.fuel The design value C for the CO2 concentration in gaseous fuels. CO2.fuel.d The concentration C of CO2 in the alternative gaseous fuel collected CO2.fuel The design value C for the N2 concentration in gaseous fuel. N2.fuel.d The concentration C of N2 in the gaseous fuel used for replacement N2.fuel Humidity design value h for gaseous fuels g.d Humidity h of the gaseous fuel used for replacement g Repeat steps S1 and S2 to obtain the corrected boiler fuel efficiency η′. xz .

[0228] S4. Calculate the heat absorption Q of the economizer on the superheater side. SH-Eco The reheater side economizer heat absorption Q RH-Eco The heat absorbed by the air-cooled wall, Q GWC The superheater absorbs heat Q SH The heat absorbed by the reheater, Q RH And the heat absorption Q of the cooling water system Cooling Finally, the total heat absorption of the boiler, Q, is obtained. sum And the proportion of heat exchanged on each heat exchange surface. Step S4 specifically involves:

[0229] S4-1. Obtaining the heat absorption of the air-cooled wall: Utilizing the collected main supply gas mass flow rate D GWC.in Main feed gas temperature t GWC.in Main air supply pressure p GWC.in t of working fluid at the outlet of the air-cooled wall GWC.out The working fluid pressure at the outlet of the air-cooled wall, p GWC.out Q is obtained by absorbing heat from the air-cooled wall. GWC :

[0230] Q GWC =D GWC.in (H GWC.out -H GWC.in ) (Formula 49);

[0231] Among them, H GWC.in The enthalpy of the working fluid at the inlet of the air-cooled wall, and H GWC.in The main feed gas temperature t was collected. GWC.in and main supply air pressure p GWC.in Find the enthalpy of carbon dioxide in the table; H GWC.out The enthalpy of the working fluid at the outlet of the air-cooled wall, and H GWC.out The working fluid temperature t at the outlet of the air-cooled wall was collected. GWC.out and the working fluid pressure p at the outlet of the air-cooled wall GWC.out Find the enthalpy of carbon dioxide in the table.

[0232] S4-2. Obtaining the heat absorbed by the superheater: using the collected superheater working fluid mass flow rate D SH.out Superheater working fluid outlet temperature t SH.out Superheater working fluid outlet pressure p SH.out Superheater working fluid inlet temperature t SH.in Superheater working fluid inlet pressure p SH.in To obtain the heat absorbed by the superheater, Q SH :

[0233] Q SH =D SH.out (H SH.out -H SH.in ) (Formula 50);

[0234] Among them, H SH.out The enthalpy of the working fluid at the superheater outlet, and H SH.out The superheater working fluid outlet temperature t was collected. SH.out and the superheater working fluid outlet pressure p SH.out Find the enthalpy of carbon dioxide in the table; H SH.in The enthalpy of the working fluid at the superheater inlet, and H SH.in The superheater working fluid inlet temperature t was collected. SH.in and superheater working fluid inlet pressure pSH.in Find the enthalpy of carbon dioxide in the table.

[0235] S4-3. Obtaining the heat absorption of the reheater: using the collected reheater working fluid mass flow rate D RH.out Reheater working fluid outlet temperature t RH.out Reheater working fluid outlet pressure p RH.out Reheater working fluid inlet temperature t RH.in Reheater working fluid inlet pressure p RH.in To obtain the heat absorbed by the reheater, Q RH :

[0236] Q RH =D RH.out (H RH.out -H RH.in ) (Formula 51);

[0237] Among them, H RH.out The enthalpy of the working fluid at the reheater outlet, and H RH.out The reheater working fluid outlet temperature t was collected. RH.out and reheater working fluid outlet pressure p RH.out Find the enthalpy of carbon dioxide in the table; H RH.in The enthalpy of the working fluid at the reheater inlet, and H RH.in The reheater working fluid inlet temperature t was collected. RH.in and reheater working fluid inlet pressure p RH.in Find the enthalpy of carbon dioxide in the table.

[0238] S4-4. Obtain the heat absorption of the economizer on the superheater side: using the collected mass flow rate D of the working fluid in the economizer on the superheater side. SH-Eco.in superheater side economizer working fluid inlet temperature t SH-Eco.SCO2.in Superheater side economizer working fluid inlet pressure p SH-Eco.SCO2.in Superheater side economizer working fluid outlet temperature t SH-Eco.SCO2.out Superheater side economizer working fluid outlet pressure p SH-Eco.SCO2.out To obtain the heat absorption Q of the economizer on the superheater side SH-Eco :

[0239] Q SH-Eco =D SH-Eco.in (H SH-Eco.out -H SH-Eco.in ) (Formula 52);

[0240] Among them, H SH-Eco.out The enthalpy of the working fluid at the economizer outlet on the superheater side, and H SH-Eco.out The collected economizer working fluid outlet temperature t on the superheater side SH-Eco.SCO2.out and the working fluid outlet pressure p of the economizer on the superheater side SH-Eco.SCO2.outFind the enthalpy of carbon dioxide in the table; H SH-Eco.in The enthalpy of the working fluid at the economizer inlet on the superheater side, and H SH-Eco.in The collected economizer working fluid inlet temperature t on the superheater side SH-Eco.SCO2.in and the working fluid inlet pressure p of the economizer on the superheater side SH-Eco.SCO2.in Find the enthalpy of carbon dioxide in the table.

[0241] S4-5. Obtain the heat absorption of the economizer on the reheater side: using the collected mass flow rate D of the working fluid in the economizer on the reheater side. RH-Eco.in Economizer working fluid inlet temperature t on the reheater side RH-Eco.SCO2.in The reheater side economizer working fluid inlet pressure p RH-Eco.SCO2.in Economizer working fluid outlet temperature t on the reheater side RH-Eco.SCO2.out The reheater side economizer working fluid outlet pressure p RH-Eco.SCO2.out To obtain the heat absorption Q of the economizer on the reheater side RH-Eco :

[0242] Q RH-Eco =D RH-Eco.in (H RH-Eco.out -H RH-Eco.in ) (Formula 53);

[0243] Among them, H RH-Eco.out The enthalpy of the working fluid at the economizer outlet on the reheater side, and H RH-Eco.out The reheater side economizer working fluid outlet temperature t was collected. RH-Eco.SCO2.out and the reheater side economizer working fluid outlet pressure p RH-Eco.SCO2.out Find the enthalpy of carbon dioxide in the table; H RH-Eco.in The enthalpy of the working fluid at the economizer inlet on the reheater side, and H RH-Eco.in The reheater side economizer working fluid inlet temperature t was collected. RH-Eco.SCO2.in and the reheater side economizer working fluid inlet pressure p RH-Eco.SCO2.in Find the enthalpy of carbon dioxide in the table.

[0244] S4-6. Obtaining the heat absorption of the cooling water system: Utilizing the collected mass flow rate q of the cooling water entering the boiler system boundary. m.cw Cooling water temperature at the outlet of the cooling equipment (t) cw.lv Cooling water pressure at the outlet of the cooling equipment p cw.lv Cooling water temperature at the inlet of the cooling equipment (t) cw.en Cooling water pressure at the inlet of the cooling equipment p cw.en To obtain the heat absorption Q of the cooling water system Cooling :

[0245] Q Cooling =q m.cw (H cw.lv -H cw.in) (Formula 54);

[0246] Among them, H cw.in The enthalpy of the working fluid at the inlet of the cooling equipment, and H cw.in The collected cooling water temperature t at the inlet of the cooling equipment cw.en and cooling water pressure at the inlet of the cooling equipment p cw.en Find the enthalpy values ​​of water and water vapor in the table; H cw.lv The enthalpy of the working fluid at the outlet of the cooling equipment, and H cw.lv The collected cooling water temperature t at the outlet of the cooling equipment cw.lv and cooling water pressure at the outlet of the cooling equipment p cw.lv Find the enthalpy values ​​of water and water vapor in the table;

[0247] S4-7. Obtain the total heat absorption of the boiler: using the heat absorption Q of the air-cooled wall calculated in step S4-1. GWC The heat absorption Q of the superheater calculated in step S4-2 SH The heat absorption Q of the reheater calculated in step S4-3 RH The heat absorption Q of the economizer on the superheater side is calculated in step S4-4. SH-Eco The heat absorption Q of the economizer on the reheater side is calculated in steps S4-5. RH-Eco The heat absorption Q of the cooling water system calculated in step S4-6 Cooling To obtain the total heat absorption Q of the boiler sum :

[0248] Q sum =Q SH-Eco +Q RH-Eco +Q GCW +Q SH +Q RH +Q Cooling (Formula 55);

[0249] S4-8. Using the heat absorption Q of the air-cooled wall calculated in step S4-1 GWC The total heat absorption Q of the boiler calculated in step S4-7 sum To obtain the heat exchange ratio α of the air-cooled wall GCW :

[0250]

[0251] S4-9. Using the heat absorption Q of the superheater calculated in step S4-2 SH The total heat absorption Q of the boiler calculated in step S4-7 sum To obtain the proportion of heat exchanged by the superheater, α SH :

[0252]

[0253] S4-10. Using the heat absorption Q of the reheater calculated in step S4-3 RH The total heat absorption Q of the boiler calculated in step S4-7 sum The proportion of reheater heat exchange α is obtained. RH :

[0254]

[0255] S4-11. Calculate the heat absorption Q of the economizer on the superheater side using the method in step S4-4. SH-Eco The total heat absorption Q of the boiler calculated in step S4-7 sum The proportion of heat exchanged by the economizer on the superheater side, α SH-Eco :

[0256]

[0257] S4-12. The heat absorption Q of the economizer on the reheater side calculated in step S4-5. RH-Eco The total heat absorption Q of the boiler calculated in step S4-7 sum To obtain the proportion of reheater-side economizer heat exchange α RH-Eco :

[0258]

[0259] S4-13. Using the heat absorption Q of the cooling water system calculated in step S4-6 Cooling The total heat absorption Q of the boiler calculated in step S4-7 sum The proportion of heat removed by the circulating cooling water, α Cooling :

[0260]

[0261] S5. Utilize the collected economizer working fluid inlet temperature t on the superheater side. SH-Eco.SCO2.in Superheater side economizer working fluid outlet temperature t SH-Eco.SCO2.out Superheater side economizer flue gas inlet temperature t SH-Eco.gas.in The reheater side economizer working fluid inlet temperature t RH-Eco.SCO2.in The reheater side economizer working fluid outlet temperature t RH-Eco.SCO2.out The reheater side economizer flue gas inlet temperature t RH-Eco.gas.in Main feed gas temperature t GWC.in The working fluid temperature at the outlet of the air-cooled wall is t GWC.out air-cooled wall flue gas inlet temperature t GWC.gas.in Superheater working fluid outlet temperature t SH.out Superheater working fluid inlet temperature t SH.in Superheater flue gas inlet temperature t SH.gas.in Reheater working fluid outlet temperature t RH.outReheater working fluid inlet temperature t RH.in Reheater flue gas inlet temperature t RH.gas.in Calculate the characteristic coefficient η of the temperature difference at the cold end of the economizer on the superheater side. SH-Eco η, the characteristic coefficient of the cold end temperature difference of the economizer on the reheater side RH-Eco η, the characteristic coefficient of cold end temperature difference of air-cooled wall GCW η, the characteristic coefficient of the cold end temperature difference of the superheater SH The reheater cold end temperature difference characteristic coefficient η RH The details are as follows:

[0262]

[0263]

[0264]

[0265]

[0266]

[0267] Specific Implementation Method Two: The difference between this implementation method and Specific Implementation Method One is that the variable data collected from the unit's DCS data, online flue gas measurement data, fuel monitoring data, boiler heat dissipation monitoring data, and environmental parameter measurement data can be the average value of 2 hours, 4 hours, 8 hours, or 168 hours. The corresponding output boiler fuel efficiency η′ reflects the boiler fuel efficiency over the entire time period of 2 hours, 4 hours, 8 hours, or 168 hours.

[0268] Specific Implementation Method Three: The performance evaluation method for supercritical carbon dioxide gas-fired boilers described in Specific Implementation Method One is fully integrated using Python 3.2. The program architecture is as follows: Figure 2 As shown, it comprises a user layer, a user interface layer, a computation layer, and a data layer. The interactive user interface, built using PYQT5, is used for user data input and display, user-defined requirements, and access to data from distributed control systems in engineering sites. The performance calculation algorithm is implemented using Python 3.2, and a data storage system based on Structured Query Language is provided. An example of the program interface is shown below. Figure 3 As shown.

[0269] The integrated program discusses the performance evaluation of boiler operation under a specific condition. Based on on-site test data (partial data shown in Table 1), the program calculates the performance results for this case (as shown in Table 2).

[0270] The flue gas heat loss is 6.03% (corrected to 5.98%), the percentage of incomplete combustion of gas, external heat and lower heating value of fuel are negligible (two significant figures), heat dissipation loss is 0.64%, and other heat losses (circulating cooling water) are 1.29%. The final calculated boiler fuel efficiency is 92.05% without correction. After correcting for flue gas heat loss, inlet air temperature and economizer feed gas temperature, the boiler fuel efficiency is corrected to 93.79%.

[0271] In terms of heat exchange surface performance, the air-cooled wall accounts for the highest heat absorption rate at 54.81% of the total heat exchange; followed by the reheater at 18.07% and the superheater at 16.62%; the two parallel economizers account for a combined 9.11% of the heat absorption; and the circulating water accounts for 1.38%. Among other performance indicators, the air preheater flue gas side heat exchange efficiency is 67.32%, the working fluid system pressure drop is 1.03 MPa, and the flue gas NOx emission concentration is less than 30 ppm.

[0272] Table 1 summarizes the measurement results of some key parameters.

[0273]

[0274] Table 2 Summary of performance calculation results

[0275]

[0276] The embodiments described above further illustrate the purpose, technical solution, and beneficial effects of this application. It should be understood that the above descriptions are merely embodiments of this application and are not intended to limit the scope of protection of this application. Any modifications, equivalent substitutions, improvements, etc., made based on the technical solution of this application should be included within the scope of protection of this application.

Claims

1. A performance evaluation method for supercritical carbon dioxide gas-fired boilers, characterized in that, include: S1. Establish a dynamic storage database to calculate the heat loss from flue gas (Q2), heat loss from incomplete combustion of gas (Q3), heat loss from heat dissipation (Q5), and external heat (Q). ex Other heat losses Q oth Input heat Q in And the effective heat output Q of the boiler system out ; Among them, the heat loss Q5 obtained from heat dissipation and other heat losses Q oth The specific steps are as follows: S16-1, Based on the heat loss from flue gas Q2, the heat loss from incomplete combustion of gas Q3, and the external heat Q... ex Input heat Q in To obtain the initial boiler fuel efficiency η0: S16-2, Based on the input heat Q in The effective heat output Q of the boiler system out And the initial boiler fuel efficiency η0, to obtain the fuel consumption q m.f : S16-3, Based on fuel consumption q m.f and the collected mass flow rate q of cooling water entering the boiler system boundary m.cw To obtain the initial other heat losses Q oth.0 : Among them, H cw.lv The enthalpy of the cooling water at the outlet of the cooling equipment, and H cw.lv The collected cooling water temperature t at the outlet of the cooling equipment cw.lv and cooling water pressure at the outlet of the cooling equipment p cw.lv Find the enthalpy values ​​of water and water vapor in the table; H cw.en The enthalpy of the cooling water at the inlet of the cooling equipment, and H cw.en The collected cooling water temperature t at the inlet of the cooling equipment cw.en and cooling water pressure at the inlet of the cooling equipment p cw.en Find the enthalpy values ​​of water and water vapor in the table; S16-4. Utilizing the collected ambient temperature t near the boiler body a3 The surface temperature T of the outer wall of the i-th mesh wi To obtain the heat transfer coefficient α of the i-th mesh method. i : Where i = 1, 2, 3...n, n is the upper limit of the number of grids in the mesh method; ε is the surface thermal emissivity, a fixed value of 0.8; σ is the radiation constant, a fixed value of 5.670373 × 10⁻⁶. -8 W·m -2 ·K -4 ; S16-5, Utilizing the collected ambient temperature t near the boiler body a3 The surface temperature T of the outer wall of the i-th mesh wi And the heat transfer coefficient α of the i-th mesh obtained in step S16-4. i Obtain the heat flux density q of the i-th mesh. i : q i = α i (T wi -t a3 -273.15) (Official 42); S16-6, Using the collected i-th grid method, the grid area A is... i and fuel consumption q m.f Heat flux density q i Obtain the initial heat loss Q 5,0 : S16-7, Based on the heat loss from flue gas Q2, the heat loss from incomplete combustion of gas Q3, and the external heat Q... ex Input heat Q in Initial other heat losses Q oth,0 and initial heat loss Q 5,0 To obtain the iterative boiler fuel efficiency η 0.dd : S16-8, Utilizing iterative boiler fuel efficiency η 0.dd The initial boiler fuel efficiency η0 in formula 39 is replaced to complete the calculation of fuel consumption q. m.f Updates and fixes; S16-9, Determine the fuel consumption q between two consecutive updates before and after the update. m.f If the absolute value of the difference is less than 0.01%, proceed to step S16-10 if the result is no; otherwise, proceed to step S16-11. S16-10, Update fuel consumption q m.f Substitute formulas 40 and 43, and repeat steps S16-7 and S16-8 in sequence to obtain the updated fuel consumption q. m.f Proceed to step S16-9; S16-11, Update fuel consumption q m.f Substituting into Equations 40 and 43, we obtain the corrected other heat losses Q. oth Heat loss due to heat dissipation Q5; S2, based on the heat loss from exhaust Q2, the heat loss from incomplete combustion Q3, the heat loss from heat dissipation Q5, and the external heat Q... ex Other heat losses Q oth and input heat Q in Find the boiler fuel efficiency η′: S3, calculate the corrected boiler fuel efficiency η′ xz Specifically, this refers to the measured flue gas temperature t. ds Make corrections to obtain the corrected flue gas temperature t. fg.AH.lv.cr.fw Using the corrected flue gas temperature t fg.AH.lv.cr.fw Replaces flue gas temperature t ds Design value t of inlet air temperature for air preheater a.AH.en.d Instead of measuring the air preheater inlet air temperature t a1 Replace the measured boiler fuel composition data with the boiler design fuel composition data, and repeat steps S1 and S2 to obtain the corrected boiler fuel efficiency η′. xz ; S4. Calculate the heat absorption Q of the economizer on the superheater side. SH-Eco The reheater side economizer heat absorption Q RH-Eco The heat absorbed by the air-cooled wall, Q GWC The superheater absorbs heat Q SH The heat absorbed by the reheater, Q RH And the heat absorption Q of the cooling water system Cooling Finally, the total heat absorption of the boiler, Q, is obtained. sum And the proportion of heat exchanged on each heat exchange surface; S5. Calculate the temperature difference characteristic coefficient η at the cold end of the economizer on the superheater side. SH-Eco η, the characteristic coefficient of the cold end temperature difference of the economizer on the reheater side RH-Eco η, the characteristic coefficient of cold end temperature difference of air-cooled wall GCW η, the characteristic coefficient of the cold end temperature difference of the superheater SH The reheater cold end temperature difference characteristic coefficient η RH The cold-end temperature difference characteristic coefficient is used to reflect the proportion of residual heat after heat transfer in the heat exchanger. A low value indicates that the heat exchanger has good overall heat transfer performance.

2. The performance evaluation method for supercritical carbon dioxide gas-fired boilers according to claim 1, characterized in that, The specific steps of S3 are as follows: S3-1, Using the design value t of the air preheater inlet air temperature a.AH.en.d The measured flue gas temperature at the inlet of the air preheater was collected. fg.AH.en.m Measured flue gas temperature at the outlet of the air preheater (t) fg.AH.lv.m The measured inlet air temperature t of the air preheater a1 The flue gas temperature t is obtained by converting it to the inlet air temperature of the designed air preheater. fg.AH.lv.cr.a : S3-2. Calculate the flue gas temperature t based on the converted air temperature at the inlet air temperature of the air preheater obtained in step S3-1. fg.AH.lv.cr.a And the collected economizer flue gas inlet temperature t on the superheater side. SH-Eco.gas.in Superheater side economizer flue gas outlet temperature t fg.Eco.lv.SH Measured economizer feed gas temperature t Eco.in Measured flue gas temperature at the inlet of the air preheater (t) fg.AH.en.m Economizer feed gas temperature design value t fw.Eco.d Design value t of air preheater inlet air temperature a.AH.en.d The flue gas temperature t is obtained from the superheater side and converted to the design air preheater inlet air temperature. fg.AH.lv.cr.fw.SH : S3-3, Calculate the flue gas temperature t based on the converted air temperature at the inlet air temperature of the air preheater obtained in step S3-1. fg.AH.lv.cr.a And the collected reheater side economizer flue gas inlet temperature t RH-Eco.gas.in The reheater side economizer flue gas outlet temperature t fg.Eco.lv.RH Measured economizer feed gas temperature t Eco.in Measured flue gas temperature at the inlet of the air preheater (t) fg.AH.en.m The reheater side economizer flue gas outlet temperature t fg.Eco.lv.RH Design economizer feed gas temperature t fw.Eco.d Design value t of air preheater inlet air temperature a.AH.en.d The flue gas temperature t is obtained from the reheater side and converted to the design air preheater inlet air temperature. fg.AH.lv.cr.fw.RH : S3-4. Utilize the collected economizer working fluid mass flow rate D on the superheater side. SH-Eco.in Reheater side economizer working fluid mass flow rate D RH-Eco.in The flue gas temperature t of the S3-2 superheater side is converted to the designed air preheater inlet air temperature. fg.AH.lv.cr.fw.SH The flue gas temperature t of the S3-3 reheater side is converted to the designed air preheater inlet air temperature. fg.AH.lv.cr.fw.RH The correction t for the total feed gas temperature on the flue gas temperature is obtained. fg.AH.lv.cr.fw : S3-5, using the corrected flue gas temperature t fg.AH.lv.cr.fw Replaces flue gas temperature t ds Design value t of inlet air temperature for air preheater a.AH.en.d Instead of measuring the air preheater inlet air temperature t a1 Replace the measured boiler fuel composition data with the boiler design fuel composition data, and repeat steps S1 and S2 to obtain the corrected boiler fuel efficiency η′. xz .

3. The performance evaluation method for supercritical carbon dioxide gas-fired boilers according to claim 2, characterized in that, The specific step S3-5 is as follows: using the corrected flue gas temperature t obtained in step S3-4... fg.AH.lv.cr.fw Replaces the collected flue gas temperature t ds Design value t of inlet air temperature for air preheater a.AH.en.d (°C) replaces the collected air preheater inlet air temperature t a1 (°C), Design value of CO concentration in gaseous fuel C CO.fuel.d The concentration C of CO in the gaseous fuel used for replacement CO.fuel The design value C for the concentration of H2 in gaseous fuel. H2.fuel.d The concentration C of H2 in the gaseous fuel used for replacement H2.fuel The design value C for the concentration of H2S in gaseous fuel. H2S.fuel.d The concentration C of H2S in the alternative gaseous fuel was used for sampling. H2S.fuel The design value C for the concentration of CH4 in gaseous fuel. CH4.fuel.d The concentration C of CH4 in the alternative gaseous fuel collected CH4.fuel The design value C2H6 concentration in the gaseous fuel. C2H6.fuel.d The concentration C2H6 in the alternative gaseous fuel is C C2H6.fuel The design value of C3H8 concentration in gaseous fuel C C3H8.fuel.d The concentration C3H8 in the gaseous fuel that was replaced by the collected gaseous fuel C3H8.fuel Using gaseous fuels containing C4H 10 Concentration design value C C4H10.fuel.d Replace the collected gaseous fuel C4H 10 Concentration C C4H10.fuel C5H in gaseous fuel 12 Concentration design value C C5H12.fuel.d Replace the collected gaseous fuel C5H 12 Concentration C C5H12.fuel The design value of C2H4 concentration in gaseous fuel C C2H4.fuel.d The concentration C2H4 in the alternative gaseous fuel is C C2H4.fuel The design value of C3H6 concentration in gaseous fuel C C3H6.fuel.d The concentration C3H6 in the gaseous fuel that was replaced by the collected gaseous fuel C3H6.fuel The design value of C4H8 concentration in gaseous fuel C C4H8.fuel.d The concentration C4H8 in the alternative gaseous fuel is C C4H8.fuel The design value C for the O2 concentration in gaseous fuel. O2.fuel.d The concentration C of O2 in the alternative gaseous fuel collected O2.fuel The design value C for the CO2 concentration in gaseous fuels. CO2.fuel.d The concentration C of CO2 in the alternative gaseous fuel collected CO2.fuel The design value C for the N2 concentration in gaseous fuel. N2.fuel.d The concentration C of N2 in the gaseous fuel used for replacement N2.fuel Humidity design value h for gaseous fuels g.d Humidity h of the gaseous fuel used for replacement g Repeat steps S1 and S2 to obtain the corrected boiler fuel efficiency η′. xz .

4. The performance evaluation method for supercritical carbon dioxide gas-fired boilers according to claim 3, characterized in that, The specific steps of S4 are as follows: S4-1, Obtaining heat absorption from the air-cooled wall Using the collected main feed gas mass flow rate D GWC.in Main feed gas temperature t GWC.in Main air supply pressure p GWC.in t of working fluid at the outlet of the air-cooled wall GWC.out The working fluid pressure at the outlet of the air-cooled wall, p GWC.out Q is obtained by absorbing heat from the air-cooled wall. GWC : Q GWC =D GWC.in (H GWC.out -H GWC.in ) (Formula 49); Among them, H GWC.in The enthalpy of the working fluid at the inlet of the air-cooled wall, and H GWC.in The main feed gas temperature t was collected. GWC.in and main supply air pressure p GWC.in Find the enthalpy of carbon dioxide in the table; H GWC.out The enthalpy of the working fluid at the outlet of the air-cooled wall, and H GWC.out The working fluid temperature t at the outlet of the air-cooled wall was collected. GWC.out and the working fluid pressure p at the outlet of the air-cooled wall GWC.out Find the enthalpy of carbon dioxide in the table. S4-2, Obtaining heat absorption from the superheater Using the collected superheater working fluid mass flow rate D SH.out Superheater working fluid outlet temperature t SH.out Superheater working fluid outlet pressure p SH.out Superheater working fluid inlet temperature t SH.in Superheater working fluid inlet pressure p SH.in To obtain the heat absorbed by the superheater, Q SH : Q SH =D SH.out (H SH.out -H SH.in ) (Formula 50); Among them, H SH.out The enthalpy of the working fluid at the superheater outlet, and H SH.out The superheater working fluid outlet temperature t was collected. SH.out and the superheater working fluid outlet pressure p SH.out Find the enthalpy of carbon dioxide in the table; H SH.in The enthalpy of the working fluid at the superheater inlet, and H SH.in The superheater working fluid inlet temperature t was collected. SH.in and superheater working fluid inlet pressure p SH.in Find the enthalpy of carbon dioxide in the table. S4-3, Obtain heat absorption from the reheater Using the collected reheater working fluid mass flow rate D RH.out Reheater working fluid outlet temperature t RH.out Reheater working fluid outlet pressure p RH.out Reheater working fluid inlet temperature t RH.in Reheater working fluid inlet pressure p RH.in To obtain the heat absorbed by the reheater, Q RH : Q RH =D RH.out (H RH.out -H RH.in ) (Formula 51); Among them, H RH.out The enthalpy of the working fluid at the reheater outlet, and H RH.out The reheater working fluid outlet temperature t was collected. RH.out and reheater working fluid outlet pressure p RH.out Find the enthalpy of carbon dioxide in the table; H RH.in The enthalpy of the working fluid at the reheater inlet, and H RH.in The reheater working fluid inlet temperature t was collected. RH.in and reheater working fluid inlet pressure p RH.in Find the enthalpy of carbon dioxide in the table. S4-4, Obtaining the heat absorption of the economizer on the superheater side. Utilizing the collected economizer working fluid mass flow rate D on the superheater side SH-Eco.in superheater side economizer working fluid inlet temperature t SH-Eco.SCO2.in Superheater side economizer working fluid inlet pressure p SH-Eco.SCO2.in Superheater side economizer working fluid outlet temperature t SH-Eco.SCO2.out Superheater side economizer working fluid outlet pressure p SH-Eco.SCO2.out To obtain the heat absorption Q of the economizer on the superheater side SH -Eco: Q SH-Eco =D SH-Eco.in (H SH-Eco.out -H SH-Eco.in ) (Formula 52); Wherein, HSH-Eco.out is the enthalpy of the working fluid at the economizer outlet on the superheater side, and H SH-Eco.out The collected economizer working fluid outlet temperature t on the superheater side SH-Eco.SCO2.out and the working fluid outlet pressure p of the economizer on the superheater side SH-Eco.SCO2.out Find the enthalpy of carbon dioxide in the table; H SH-Eco.in The enthalpy of the working fluid at the economizer inlet on the superheater side, and H SH-Eco.in The collected economizer working fluid inlet temperature t on the superheater side SH-Eco.SCO2.in and the working fluid inlet pressure p of the economizer on the superheater side SH-Eco.SCO2.in Find the enthalpy of carbon dioxide in the table. S4-5, Obtain the heat absorption of the economizer on the reheater side. Utilizing the collected reheater-side economizer working fluid mass flow rate D RH-Eco.in Economizer working fluid inlet temperature t on the reheater side RH-Eco.SCO2.in The reheater side economizer working fluid inlet pressure p RH-Eco.SCO2.in Economizer working fluid outlet temperature t on the reheater side RH-Eco.SCO2.out The reheater side economizer working fluid outlet pressure p RH-Eco.SCO2.out To obtain the heat absorption Q of the economizer on the reheater side RH-Eco : Q RH-Eco =D RH-Eco.in (H RH-Eco.out -H RH-Eco.in ) (Formula 53); Among them, H RH-Eco.out The enthalpy of the working fluid at the economizer outlet on the reheater side, and H RH-Eco.out The reheater side economizer working fluid outlet temperature t was collected. RH-Eco.SCO2.out and the reheater side economizer working fluid outlet pressure p RH-Eco.SCO2.out Find the enthalpy of carbon dioxide in the table; H RH-Eco.in The enthalpy of the working fluid at the economizer inlet on the reheater side, and H RH-Eco.in The reheater side economizer working fluid inlet temperature t was collected. RH-Eco.SCO2.in and the reheater side economizer working fluid inlet pressure p RH-Eco.SCO2.in Find the enthalpy of carbon dioxide in the table. S4-6, Obtaining heat absorption from the cooling water system Using the collected mass flow rate q of cooling water entering the boiler system boundary m.cw Cooling water temperature at the outlet of the cooling equipment (t) cw.lv Cooling water pressure at the outlet of the cooling equipment p cw.lv Cooling water temperature at the inlet of the cooling equipment (t) cw.en Cooling water pressure at the inlet of the cooling equipment p cw.en To obtain the heat absorption Q of the cooling water system Cooling : Q Cooling =q m.cw (H cw.lv -H cw.in ) (Formula 54); Among them, H cw.in The enthalpy of the working fluid at the inlet of the cooling equipment, and H cw.in The collected cooling water temperature t at the inlet of the cooling equipment cw.en and cooling water pressure at the inlet of the cooling equipment p cw.en Find the enthalpy values ​​of water and water vapor in the table; H cw.lv The enthalpy of the working fluid at the outlet of the cooling equipment, and H cw.lv The collected cooling water temperature t at the outlet of the cooling equipment cw.lv and cooling water pressure at the outlet of the cooling equipment p cw.lv Find the enthalpy values ​​of water and water vapor in the table; S4-7. Obtain the total heat absorption of the boiler. The heat absorption Q of the air-cooled wall calculated in step S4-1 GWC The heat absorption Q of the superheater calculated in step S4-2 SH The heat absorption Q of the reheater calculated in step S4-3 RH The heat absorption Q of the economizer on the superheater side is calculated in step S4-4. SH-Eco The heat absorption Q of the economizer on the reheater side is calculated in steps S4-5. RH-Eco The heat absorption Q of the cooling water system calculated in step S4-6 Cooling To obtain the total heat absorption Q of the boiler sum : Q sum =Q SH-Eco +Q RH-Eco +Q GCW +Q SH +Q RH +Q Cooling (Official 55); S4-8. Using the heat absorption Q of the air-cooled wall calculated in step S4-1 GWC The total heat absorption of the boiler, Q, calculated in step S4-7. sum To obtain the heat exchange ratio α of the air-cooled wall GCW : S4-9. Using the heat absorption Q of the superheater calculated in step S4-2 SH The total heat absorption of the boiler, Q, calculated in step S4-7. sum To obtain the proportion of heat exchanged by the superheater, α SH : S4-10. Using the heat absorption Q of the reheater calculated in step S4-3 RH The total heat absorption of the boiler, Q, calculated in step S4-7. sum The proportion of reheater heat exchange α is obtained. RH : S4-11. Calculate the heat absorption Q of the economizer on the superheater side using the method in step S4-4. SH-Eco The total heat absorption of the boiler, Q, calculated in step S4-7. sum The proportion of heat exchanged by the economizer on the superheater side, α SH-Eco : S4-12. The heat absorption Q of the economizer on the reheater side calculated in step S4-5. RH-Eco The total heat absorption of the boiler, Q, calculated in step S4-7. sum To obtain the proportion of reheater-side economizer heat exchange α RH-Eco : S4-13. Using the heat absorption Q of the cooling water system calculated in step S4-6 Cooling The total heat absorption of the boiler, Q, calculated in step S4-7. sum The proportion of heat removed by the circulating cooling water, α Cooling :

5. The performance evaluation method for supercritical carbon dioxide gas-fired boilers according to claim 4, characterized in that, The specific steps of S5 are as follows: Using the collected economizer working fluid inlet temperature t on the superheater side SH-Eco.SCO2.in Superheater side economizer working fluid outlet temperature t SH-Eco.SCO2.out Superheater side economizer flue gas inlet temperature t SH-Eco.gas.in The reheater side economizer working fluid inlet temperature t RH-Eco.SCO2.in The reheater side economizer working fluid outlet temperature t RH-Eco.SCO2.out The reheater side economizer flue gas inlet temperature t RH-Eco.gas.in Main feed gas temperature t GWC.in The working fluid temperature at the outlet of the air-cooled wall is t GWC.out air-cooled wall flue gas inlet temperature t GWC.gas.in Superheater working fluid outlet temperature t SH.out Superheater working fluid inlet temperature t SH.in Superheater flue gas inlet temperature t SH.gas.in Reheater working fluid outlet temperature t RH.out Reheater working fluid inlet temperature t RH.in Reheater flue gas inlet temperature t RH.gas.in Calculate the characteristic coefficient η of the temperature difference at the cold end of the economizer on the superheater side. SH-Eco η, the characteristic coefficient of the cold end temperature difference of the economizer on the reheater side RH-Eco η, the characteristic coefficient of cold end temperature difference of air-cooled wall GCW η, the characteristic coefficient of the cold end temperature difference of the superheater SH The reheater cold end temperature difference characteristic coefficient η RH The details are as follows:

Images