A method for industrial steam combined heat and power operation

Abstract

A method for operating industrial steam cogeneration includes the following steps: For each unit, a suitable extraction steam location is selected as the high-pressure drive steam and low-pressure intake steam source for the pressure matcher; a variable operating condition model for the extraction-condensing unit is established; based on the variable operating condition model, the relationship between the unit's power generation coal consumption rate and the high-pressure drive steam quantity, low-pressure intake steam quantity, and power generation is fitted; preliminary allocation of the unit's industrial heat load is performed based on the current power generation of each unit, industrial steam demand, industrial steam target parameters, and the sum of the maximum industrial extraction steam quantities corresponding to the two extraction steam locations for each unit; an initial ejector coefficient is set, and the ejector coefficient of the pressure matcher is determined based on the expansion ratio and compression ratio under actual operating conditions; the high-pressure drive steam quantity, low-pressure intake steam quantity, and industrial steam supply quantity for each unit are determined through continuous iteration. This invention can rationally allocate the industrial heat load according to the industrial steam demand under actual unit operating conditions, ensuring the reliability and economy of heating supply.

Description

Technical Field

[0001] This invention belongs to the technical field of cogeneration heating units or energy-saving projects, and specifically relates to a method for operating cogeneration using industrial steam. Background Technology

[0002] With the continuous development of my country's social economy, the demand for industrial steam supply is constantly increasing. Utilizing a portion of extracted steam for industrial steam supply during the power generation process can improve energy utilization efficiency and thus reduce cooling source losses.

[0003] In industrial steam systems, the traditional approach is to use desuperheating and pressure reduction, but this results in significant waste of steam quality. Variable operating conditions are the primary operating condition for turbine units; under different load conditions, the pressure and temperature at each extraction port will vary. To meet different heating demands, it is essential to employ reasonable heating schemes and methods to match the turbine extraction steam parameters with the industrial steam parameters, thereby satisfying heating needs while maintaining good economic efficiency. Summary of the Invention

[0004] The purpose of this invention is to provide a method for operating industrial steam cogeneration, which uses a pressure matching device to utilize a portion of low-quality steam for industrial steam supply, and allocates the heat load according to the actual operating conditions of the unit. This method achieves the requirements for industrial steam supply while minimizing the coal consumption of the unit for power generation, without the need for frequent switching and start-up / shutdown of the unit, which is conducive to energy saving and consumption reduction of the unit, and ensures the reliability and economy of the heating supply.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A method for operating industrial steam cogeneration, the method comprising the following steps:

[0007] Step 1: Select a suitable extraction steam location for each extraction condensing unit as the high-pressure drive steam and low-pressure intake steam source for the pressure matcher, and establish a variable operating condition model for the extraction condensing unit.

[0008] Step 2: Fitting the thermal power plant model based on the variable operating condition model of the extraction condensing unit. n Taiwan Condensation Unit Coal Consumption Rate b e and high-pressure driven steam volume G P Low-pressure steam intake G H Electricity generation P e Relationship:

[0009]

[0010] In the formula: i For unit serial number, ; b ei For the first i Coal consumption rate of power generation unit, g / kWh; G Pi For the first i High-pressure drive steam flow rate of the unit pressure matching device, t / h; G Hi For the first i Low-pressure steam intake rate of the unit pressure matching device, t / h; P ei For the first i Power generation of the unit, kW; A i B i C i m represents the polynomial coefficients of the fitting equation for the i-th unit; i Let be the degree of the polynomial used to fit the relation of the i-th unit.

[0011] Step 3: Based on the current power generation of each unit P ei Industrial steam demand G Industrial steam supply target parameters, and the maximum industrial steam extraction capacity of each unit corresponding to the two extraction points. G 1maxi and G 2maxi sum G i Preliminary allocation of industrial heat load for the unit:

[0012] (1) If G < G i Calculate the power generation of each unit P ei To meet the industrial steam demand G And the change in coal consumption rate for power generation, and the change in coal consumption rate. The product of the power generation and the extraction coefficient is arranged in ascending order. The ratio of the steam supply at the two extraction points, i.e., the ejector coefficient, is initially set as follows: ,Right now:

[0013]

[0014]

[0015] The preliminary method for industrial heat load allocation is as follows The corresponding generating units will receive priority steam supply;

[0016] (2) If G > G iCalculate the power generation of each unit P ei To undertake the maximum industrial steam extraction capacity of the unit G i And the change in coal consumption rate for power generation, and the change in coal consumption rate. The product of the power generation and the electricity generation is arranged in ascending order, i.e.:

[0017]

[0018]

[0019] The preliminary method for industrial heat load allocation is as follows Larger generating units are given priority for heating, with the remaining heat supplied by the next largest unit. Steam is supplied to the corresponding generating units first, and then lastly. Steam supply to the corresponding generating unit;

[0020] Step 4: (1) For G < G i In this situation, The corresponding steam supply at the two extraction points of the unit is:

[0021]

[0022] The superscript ' indicates G <G i The situation;

[0023] (2) For G > G i In this situation, for For the corresponding unit, the initial ejector coefficient u is set as follows:

[0024]

[0025] The sum of the maximum industrial steam extraction rates at the two extraction points of this unit is: G n ,but:

[0026]

[0027] Based on the above two scenarios, the corresponding unit electrical load, high-pressure drive steam quantity, and low-pressure suction steam quantity are input into the unit's extraction-condensing unit variable operating condition model. The pressure at the high-pressure drive steam extraction location is then obtained using the Flueger formula. P P and temperature T P Pressure at the low-pressure steam intake extraction point P H and temperature TH Calculate the expansion ratio E and compression ratio β :

[0028]

[0029]

[0030] In the formula: P C To meet the target pressure of industrial steam supply;

[0031] Based on the relationship curve between the ejector coefficient and the expansion ratio and compression ratio provided by the pressure matching device manufacturer, calculate the ejector coefficient u' corresponding to the expansion ratio and compression ratio, let u = u', and repeat step 4 until the absolute error values ​​of u and u' are less than the set error values.

[0032] The boundary conditions that need to be set in the calculation process are:

[0033] (1) G' Pn , G Pn The value is less than the maximum value of the steam extraction rate at the corresponding location, that is G' Pn < G 1maxn , G Pn < G 1maxn ;

[0034] (2) G' Hn , G Hn The value is less than the maximum value of the steam extraction rate at the corresponding location, that is G' Hn < G 2maxn , G Hn < G 2maxn ;

[0035] (3) The outlet pressure of the pressure matcher is the target pressure for industrial steam supply. P C Pressure at the high-pressure driven steam extraction position P P Greater than P C ,Right now P P > P C .

[0036] (4) The pressure rise ratio of low-pressure intake steam shall not exceed 2.5, i.e.P C / P H 2.5;

[0037] (5) Pressure matching device outlet temperature T C Higher than the target temperature for industrial steam extraction;

[0038] (6) G' Pn , G Pn The value shall not be less than 50% of the design flow rate provided by the pressure matching device manufacturer;

[0039] Based on the above calculations , If the corresponding unit does not meet the above conditions, the excess steam supply shall be borne by the next best unit, and the calculation steps are the same as above.

[0040] Furthermore, for multiple extraction condensing units, each extraction condensing unit shares a pressure matcher, or each extraction condensing unit is equipped with a pressure matcher.

[0041] Furthermore, in step 1, the appropriate extraction steam location is selected. For high-pressure driving steam, the steam source is selected as fresh steam, reheat cold section extraction steam, or reheat hot section extraction steam. For low-pressure suction steam, the steam source is selected as fourth-stage extraction steam or fifth-stage extraction steam.

[0042] Furthermore, regarding the maximum industrial steam extraction rate of the unit mentioned in step 3, if the steam extraction from the reheat cold section is used as the high-pressure driving steam, in order to ensure that the reheater does not overheat, the steam extraction rate shall not exceed 5% of the total steam volume of the reheat cold section.

[0043] Furthermore, the gravitational coefficient can be calculated using the following formula:

[0044]

[0045] In the formula: K m The fluid velocity coefficient within the pressure matching device. m =1, 2, 3, 4; , , These represent the critical velocities of high-pressure driven steam, low-pressure intake steam, and outlet steam, respectively. , , These represent the isentropic velocity of the driving fluid at the mixing chamber inlet section, the isentropic velocity of the intake fluid at the mixing chamber inlet section, and the isentropic velocity of the outlet fluid at the mixing chamber outlet section, respectively.

[0046] Furthermore, the gravitational coefficient is initially set to u=0.5, that is:

[0047] .

[0048] Furthermore, in actual operation, the closer the pressure matcher is to its rated parameters, the higher its efficiency. The efficiency is calculated as follows:

[0049]

[0050] In the formula: η is the efficiency of the pressure matcher; The isentropic enthalpy drop of high-pressure driven steam to low-pressure intake steam; The isentropic enthalpy drop from low-pressure intake steam to output steam; when 2 < When the pressure matching efficiency is less than 6, the ejector efficiency of the pressure matching device is high. Selecting a pressure matching device with high ejector efficiency will result in better energy saving.

[0051] Furthermore, the outlet temperature of the pressure matcher T C From the gravitation coefficient u The decision is based on the gravitational coefficient. u After balancing the energy at the inlet and outlet, the enthalpy of the steam at the outlet of the pressure matcher is calculated, and then the outlet temperature of the pressure matcher is determined. T C The formula for calculating the enthalpy of steam at the outlet of the pressure matcher is:

[0052]

[0053] In the formula: h C The enthalpy of the steam at the outlet of the pressure matcher. h p The enthalpy of high-pressure driven steam. h h The enthalpy of the low-pressure intake steam; based on the outlet steam pressure of the pressure matcher. P C enthalpy value h C Calculate the outlet temperature T C Outlet temperature T C The extraction temperature must be higher than the target temperature for industrial steam extraction to meet the requirements.

[0054] Furthermore, if the steam temperature at the outlet of the pressure matcher... T C The temperature is higher than the target temperature required for industrial steam extraction. By adding a water spray desuperheating device, the extraction volume of high-pressure driving steam and low-pressure suction steam and the volume of desuperheating water are calculated based on the laws of mass conservation and energy conservation.

[0055] Furthermore, when the industrial steam extraction volume of the secondary unit is less than 50% of the design flow rate provided by the pressure matching device manufacturer, the pressure matching device will not extract low-pressure intake steam. In this case, the pressure matching device is used as a desuperheater and pressure reducer.

[0056] The beneficial effects of this invention are: by using a pressure matching device to utilize a portion of low-quality steam for industrial steam supply, the heat load is allocated according to the actual operating conditions of the unit, and the requirements for industrial steam supply are met while minimizing the coal consumption for power generation. It eliminates the need for frequent switching and starting / stopping of the unit, which is conducive to energy conservation and consumption reduction of the unit, and ensures the reliability and economy of heating supply. Attached Figure Description

[0057] Figure 1 This is a flowchart of a method for operating industrial steam cogeneration according to an embodiment of the present invention.

[0058] Figure 2 This is a schematic diagram of a heating steam system for an industrial steam cogeneration operation method according to an embodiment of the present invention. Detailed Implementation

[0059] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0060] Please see Figure 1 This invention provides a method for operating industrial steam cogeneration, comprising the following steps:

[0061] Step 1: Select a suitable extraction steam location for each extraction condensing unit as the high-pressure drive steam and low-pressure intake steam source for the pressure matcher, and establish a variable operating condition model for the extraction condensing unit.

[0062] Step 2: Fitting the thermal power plant model based on the variable operating condition model of the extraction condensing unit. n Taiwan Condensation Unit Coal Consumption Rate b e and high-pressure driven steam volume G P Low-pressure steam intake G H Electricity generation P e Relationship:

[0063]

[0064] In the formula: i For unit serial number, ; b ei For the first i Coal consumption rate of power generation unit, g / kWh; G Pi For the first iHigh-pressure drive steam flow rate of the unit pressure matching device, t / h; G Hi For the first i Low-pressure steam intake rate of the unit pressure matching device, t / h; P ei For the first i Power generation of the unit, kW; A i B i C i The polynomial coefficients of the fitted equation for the i-th unit are determined using the least squares method; m i Let be the degree of the polynomial used to fit the relationship of the i-th unit. The value is determined based on the sum of squared errors and the correlation coefficient. The smaller the sum of squared errors and the closer the correlation coefficient is to 1, the better the fitting effect.

[0065] Step 3: Based on the current power generation of each unit P ei Industrial steam demand G Industrial steam supply target parameters, and the maximum industrial steam extraction capacity corresponding to the two extraction points for each unit. G 1maxi and G 2maxi sum G i Preliminary allocation of industrial heat load for the unit:

[0066] (1) If G < G i Calculate the power generation of each unit P ei To meet the industrial steam demand G And the change in coal consumption rate for power generation, and the change in coal consumption rate. The product of the power generation and the output power is arranged in ascending order, and the initial steam supply ratio between the two extraction points is set as follows: ,Right now:

[0067]

[0068]

[0069] The preliminary method for industrial heat load allocation is as follows The corresponding generating units will receive priority steam supply;

[0070] (2) If G > G i Calculate the power generation of each unit P ei To undertake the maximum industrial steam extraction capacity of the unit G iAnd the change in coal consumption rate for power generation, and the change in coal consumption rate. The product of the power generation and the electricity generation is arranged in ascending order, i.e.:

[0071]

[0072]

[0073] The preliminary method for industrial heat load allocation is as follows Larger generating units are given priority for heating, with the remaining heat supplied by the next largest unit. Steam is supplied to the corresponding generating units first, and then lastly. Steam supply to the corresponding generating unit;

[0074] Step 4: (1) For G < G i In this situation, The corresponding steam supply at the two extraction points of the unit is:

[0075]

[0076] The superscript ' indicates G <G i The situation;

[0077] (2) For G > G i In this situation, for For the corresponding unit, the initial ejector coefficient u is set as follows:

[0078]

[0079] The sum of the maximum industrial steam extraction rates at the two extraction points of this unit is: G n ,but:

[0080]

[0081] Based on the above two scenarios, the corresponding unit electrical load, high-pressure drive steam quantity, and low-pressure suction steam quantity are input into the unit's extraction-condensing unit variable operating condition model. The pressure at the high-pressure drive steam extraction location is then obtained using the Flueger formula. P P and temperature T P Pressure at the low-pressure steam intake extraction point P H and temperature T H Calculate the expansion ratio E and compression ratio β :

[0082]

[0083]

[0084] In the formula: P C To meet the target pressure of industrial steam supply;

[0085] Based on the relationship curve between the ejector coefficient and the expansion ratio and compression ratio provided by the pressure matching device manufacturer, calculate the ejector coefficient u' corresponding to the expansion ratio and compression ratio, let u = u', and repeat step 4 until the absolute error values ​​of u and u' are less than the set error values.

[0086] The boundary conditions that need to be set in the calculation process are:

[0087] (1) G' Pn , G Pn The value is less than the maximum value of the steam extraction rate at the corresponding location, that is G' Pn < G 1maxn , G Pn < G 1maxn ;

[0088] (2) G' Hn , G Hn The value is less than the maximum value of the steam extraction rate at the corresponding location, that is G' Hn < G 2maxn , G Hn < G 2maxn ;

[0089] (3) The outlet pressure of the pressure matcher is the target pressure for industrial steam supply. P C Pressure at the high-pressure driven steam extraction position P P Greater than P C ,Right now P P > P C .

[0090] (4) The pressure rise ratio of low-pressure intake steam shall not exceed 2.5, i.e. P C / P H 2.5;

[0091] (5) Pressure matching device outlet temperature T C Higher than the target temperature for industrial steam extraction;

[0092] (6) G' Pn , G Pn The value shall not be less than 50% of the design flow rate provided by the pressure matching device manufacturer;

[0093] Based on the above calculations , If the corresponding unit does not meet the above conditions, the excess steam supply shall be borne by the next best unit, and the calculation steps are the same as above.

[0094] In this embodiment, the pressure matching device mentioned in step 1 can be shared by all extraction condensing units, or each extraction condensing unit can be equipped with its own pressure matching device.

[0095] In this embodiment, the steam source for the high-pressure driven steam at the extraction location mentioned in step 1 can be fresh steam, reheat cold section extraction steam, reheat hot section extraction steam, etc., and the steam source for the low-pressure suction steam can be fourth-stage extraction steam, fifth-stage extraction steam, etc.

[0096] In this embodiment, the maximum industrial steam extraction rate of the unit mentioned in step 3, if the reheat cold section steam extraction is used as high-pressure driving steam, in order to ensure that the reheater does not overheat, the steam extraction rate shall not exceed 5% of the total steam volume of the reheat cold section.

[0097] In this embodiment, the entrainment coefficient mentioned in step 4 can be calculated using the following formula:

[0098]

[0099] In the formula: K m The fluid velocity coefficient within the pressure matching device. m =1, 2, 3, 4; , , These represent the critical velocities of high-pressure driven steam, low-pressure intake steam, and outlet steam, respectively. , , These represent the isentropic velocity of the driving (working) fluid at the mixing chamber inlet section, the isentropic velocity of the suction (ejector) fluid at the mixing chamber inlet section, and the isentropic velocity of the outlet (compressed) fluid at the mixing chamber outlet section, respectively.

[0100] In this embodiment, the ejection coefficient is initially set to u=0.5, that is:

[0101] .

[0102] In this embodiment, the pressure matching device described in step 4 has higher efficiency as it approaches its rated parameters during actual operation. The efficiency is calculated as follows:

[0103]

[0104] In the formula: η is the efficiency of the pressure matcher; The isentropic enthalpy drop of high-pressure driven steam to low-pressure intake steam; This refers to the isentropic enthalpy drop from low-pressure intake steam to output steam. When 2 < When the efficiency is less than 6, the pressure matching device has a higher ejection efficiency. Choosing a pressure matching device with high ejection efficiency will result in better energy saving.

[0105] In this embodiment, the pressure matching device outlet temperature mentioned in step 4 T C From the gravitation coefficient u The decision is based on the gravitational coefficient. u By balancing the energy at the inlet and outlet, and determining the enthalpy of the vapor at the outlet of the pressure matcher, the outlet temperature of the pressure matcher can be calculated. T C The formula for calculating the enthalpy of steam at the outlet of the pressure matcher is:

[0106]

[0107] In the formula: h C The enthalpy of the steam at the outlet of the pressure matcher. h p The enthalpy of high-pressure driven steam. h h This refers to the enthalpy of the low-pressure intake steam. It is determined based on the outlet steam pressure of the pressure matcher. P C enthalpy value h C The outlet temperature can then be calculated. T C Outlet temperature T C The extraction temperature must be higher than the target temperature for industrial steam extraction to meet the requirements.

[0108] In this embodiment, if the outlet steam temperature of the pressure matching device mentioned in step 4 is... T C If the temperature exceeds the target temperature for industrial steam extraction, a water spray desuperheating device can be added. The extraction volume of high-pressure driving steam and low-pressure suction steam, as well as the desuperheating water volume, can be calculated based on the laws of mass conservation and energy conservation.

[0109] In this embodiment, when the industrial steam extraction volume undertaken by the secondary unit is less than 50% of the design flow rate provided by the pressure matching device manufacturer, as described in step 4, the pressure matching device does not extract low-pressure intake steam. At this time, the pressure matching device is used as a desuperheater and pressure reducer.

[0110] Figure 2 This is a schematic diagram of a heating steam system for an industrial steam cogeneration operation method using this embodiment. The diagram only shows a system in which the high-pressure cylinder exhaust and the medium-pressure cylinder exhaust of the two units are combined to generate medium-pressure steam. If other high-pressure and low-pressure steam sources are used, only the corresponding steam extraction port positions need to be changed.

[0111] The embodiments described in this invention are merely illustrative of the method flow and should not be construed as limiting the scope of protection of this invention. Those skilled in the art can make various modifications and variations based on the above description. Any modifications, equivalent substitutions, or improvements made to the technical solution based on the technical concept proposed in this invention should be included within the scope of protection of the claims of this invention.

Claims

1. A method for operating industrial steam cogeneration, characterized in that, The method includes the following steps: Step 1: Select a suitable extraction steam location for each extraction condensing unit as the high-pressure drive steam and low-pressure intake steam source for the pressure matcher, and establish a variable operating condition model for the extraction condensing unit. Step 2: Fitting the thermal power plant model based on the variable operating condition model of the extraction condensing unit. n Taiwan Condensation Unit Coal Consumption Rate b e and high-pressure driven steam volume G P Low-pressure steam intake G H Electricity generation P e Relationship: In the formula: i For unit serial number, ; b ei For the first i Coal consumption rate of power generation unit, g / kWh; G Pi For the first i High-pressure drive steam flow rate of the unit pressure matching device, t / h; G Hi For the first i Low-pressure steam intake rate of the unit pressure matching device, t / h; P ei For the first i Power generation of the unit, kW; A i B i C i m represents the polynomial coefficients of the fitting equation for the i-th unit; i Let be the degree of the polynomial used to fit the relation of the i-th unit. Step 3: Based on the current power generation of each unit P ei Industrial steam demand G Industrial steam supply target parameters, and the maximum industrial steam extraction capacity of each unit corresponding to the two extraction points. G 1maxi and G 2maxi sum G i Preliminary allocation of industrial heat load for the unit: (1) If G < G i Calculate the power generation of each unit P ei To meet the industrial steam demand G And the change in coal consumption rate for power generation, and the change in coal consumption rate. The product of the power generation and the extraction coefficient is arranged in ascending order. The ratio of the steam supply at the two extraction points, i.e., the ejector coefficient, is initially set as follows: ,Right now: The preliminary method for industrial heat load allocation is as follows The corresponding generating units will receive priority steam supply; (2) If G > G i Calculate the power generation of each unit P ei To undertake the maximum industrial steam extraction capacity of the unit G i And the change in coal consumption rate for power generation, and the change in coal consumption rate. The product of the power generation and the electricity generation is arranged in ascending order, i.e.: The preliminary method for industrial heat load allocation is as follows Larger generating units are given priority for heating, with the remaining heat supplied by the next largest unit. Steam is supplied to the corresponding generating units first, and then lastly. Steam supply to the corresponding generating unit; Step 4: (1) For G < G i In this situation, The corresponding steam supply at the two extraction points of the unit is: The superscript ' indicates G <G i The situation; (2) For G > G i In this situation, for For the corresponding unit, the initial ejector coefficient u is set as follows: The sum of the maximum industrial steam extraction rates at the two extraction points of this unit is: G n ,but: Based on the above two scenarios, the corresponding unit electrical load, high-pressure drive steam quantity, and low-pressure suction steam quantity are input into the unit's extraction-condensing unit variable operating condition model. The pressure at the high-pressure drive steam extraction location is then obtained using the Flueger formula. P P and temperature T P Pressure at the low-pressure steam intake extraction point P H and temperature T H Calculate the expansion ratio E and compression ratio β : In the formula: P C To meet the target pressure of industrial steam supply; Based on the relationship curve between the ejector coefficient and the expansion ratio and compression ratio provided by the pressure matching device manufacturer, calculate the ejector coefficient u' corresponding to the expansion ratio and compression ratio, let u = u', and repeat step 4 until the absolute error values ​​of u and u' are less than the set error values. The boundary conditions that need to be set in the calculation process are: (1) G' Pn , G Pn The value is less than the maximum value of the steam extraction rate at the corresponding location, that is G' Pn < G 1maxn , G Pn < G 1maxn ; (2) G' Hn , G Hn The value is less than the maximum value of the steam extraction rate at the corresponding location, that is G' Hn < G 2maxn , G Hn < G 2maxn ; (3) The outlet pressure of the pressure matcher is the target pressure for industrial steam supply. P C Pressure at the high-pressure driven steam extraction position P P Greater than P C ,Right now P P > P C； (4) The pressure rise ratio of low-pressure intake steam shall not exceed 2.5, i.e. P C / P H 2.5; (5) Pressure matching device outlet temperature T C Higher than the target temperature for industrial steam extraction; (6) G' Pn , G Pn The value shall not be less than 50% of the design flow rate provided by the pressure matching device manufacturer; Based on the above calculations , If the corresponding unit does not meet the above conditions, the excess steam supply shall be borne by the next best unit, and the calculation steps are the same as above.

2. The method for operating industrial steam cogeneration according to claim 1, characterized in that, In step 1, for multiple extraction condensing units, each extraction condensing unit shares a pressure matcher, or each extraction condensing unit is equipped with a pressure matcher.

3. The method for operating industrial steam cogeneration according to claim 1, characterized in that, In step 1, the appropriate extraction steam location is selected. For high-pressure driving steam, the steam source can be fresh steam, reheat cold section extraction steam, or reheat hot section extraction steam. For low-pressure suction steam, the steam source can be fourth-stage extraction steam or fifth-stage extraction steam.

4. A method for operating industrial steam cogeneration according to claim 3, characterized in that, The maximum industrial steam extraction rate of the unit mentioned in step 3, if the reheat cold section steam extraction is used as high-pressure driving steam, in order to ensure that the reheater does not overheat, the steam extraction rate shall not exceed 5% of the total steam rate of the reheat cold section.

5. A method for operating industrial steam cogeneration according to claim 1, characterized in that, The entrainment coefficient can also be calculated using the following formula: In the formula: K m The fluid velocity coefficient within the pressure matching device. m =1, 2, 3, 4; , , These represent the critical velocities of high-pressure driven steam, low-pressure intake steam, and outlet steam, respectively. , , These represent the isentropic velocity of the driving fluid at the mixing chamber inlet section, the isentropic velocity of the intake fluid at the mixing chamber inlet section, and the isentropic velocity of the outlet fluid at the mixing chamber outlet section, respectively.

6. The method for operating industrial steam cogeneration according to claim 1, characterized in that, The initial entrainment coefficient is set to u=0.5, that is: 。 7. A method for operating industrial steam cogeneration according to claim 1, characterized in that, In actual operation, the closer the pressure matcher is to its rated parameters, the higher its efficiency. The efficiency is calculated as follows: In the formula: η is the efficiency of the pressure matcher; The isentropic enthalpy drop of high-pressure driven steam to low-pressure intake steam; The isentropic enthalpy drop from low-pressure intake steam to output steam; when 2 < When the pressure matching efficiency is less than 6, the ejector efficiency of the pressure matching device is high. Selecting a pressure matching device with high ejector efficiency will result in better energy saving.

8. A method for operating industrial steam cogeneration according to claim 1, characterized in that, Pressure matcher outlet temperature T C From the gravitation coefficient u The decision is based on the gravitational coefficient. u After balancing the energy at the inlet and outlet, the enthalpy of the steam at the outlet of the pressure matcher is calculated, and then the outlet temperature of the pressure matcher is determined. T C The formula for calculating the enthalpy of steam at the outlet of the pressure matcher is: In the formula: h C The enthalpy of the steam at the outlet of the pressure matcher. h p The enthalpy of high-pressure driven steam. h H The enthalpy of the low-pressure intake steam; based on the outlet steam pressure of the pressure matcher. P C enthalpy value h C Calculate the outlet temperature T C Outlet temperature T C The extraction temperature must be higher than the target temperature required for industrial steam extraction in order for the extraction scheme to meet the industrial steam extraction requirements.

9. A method for operating industrial steam cogeneration according to claim 1, characterized in that, If the steam temperature at the outlet of the pressure matcher T C The temperature is higher than the target temperature required for industrial steam extraction. By adding a water spray desuperheating device, the extraction volume of high-pressure driving steam and low-pressure suction steam and the volume of desuperheating water are calculated based on the laws of mass conservation and energy conservation.

10. A method for operating industrial steam cogeneration according to claim 1, characterized in that, When the industrial steam extraction volume of the secondary unit is less than 50% of the design flow rate provided by the pressure matching device manufacturer, the pressure matching device will not extract low-pressure steam. In this case, the pressure matching device is used as a desuperheater and pressure reducer.

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