CN112523824A - Heat supply system and heat supply method - Google Patents
Heat supply system and heat supply method Download PDFInfo
- Publication number
- CN112523824A CN112523824A CN202011319758.3A CN202011319758A CN112523824A CN 112523824 A CN112523824 A CN 112523824A CN 202011319758 A CN202011319758 A CN 202011319758A CN 112523824 A CN112523824 A CN 112523824A
- Authority
- CN
- China
- Prior art keywords
- steam
- parameter
- pressure
- inlet
- machine
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01K—STEAM ENGINE PLANTS; STEAM ACCUMULATORS; ENGINE PLANTS NOT OTHERWISE PROVIDED FOR; ENGINES USING SPECIAL WORKING FLUIDS OR CYCLES
- F01K17/00—Using steam or condensate extracted or exhausted from steam engine plant
- F01K17/02—Using steam or condensate extracted or exhausted from steam engine plant for heating purposes, e.g. industrial, domestic
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01K—STEAM ENGINE PLANTS; STEAM ACCUMULATORS; ENGINE PLANTS NOT OTHERWISE PROVIDED FOR; ENGINES USING SPECIAL WORKING FLUIDS OR CYCLES
- F01K13/00—General layout or general methods of operation of complete plants
- F01K13/02—Controlling, e.g. stopping or starting
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Control Of Steam Boilers And Waste-Gas Boilers (AREA)
- Engine Equipment That Uses Special Cycles (AREA)
Abstract
The application provides a heat supply system and a heat supply method, relates to the field of chemical industry, and solves the problem that the heat supply requirement with high parameters cannot be met by adopting a back pressure machine at present. The system comprises: a heat source steam pipeline, an inlet parameter adjusting valve and a back press; the inlet of the back pressure machine is communicated with the heat source steam pipeline through the inlet parameter adjusting valve, and the inlet parameter adjusting valve is used for adjusting steam parameters at the inlet of the back pressure machine. The application provides a heating system and a heating method for heating.
Description
Technical Field
The application relates to the field of chemical industry, in particular to a heat supply system and a heat supply method.
Background
Industry has developed without departing from energy supplies, where heat energy is one of the most important forms of energy utilization. The industrial heating is different according to the technological requirements, the steam parameters supplied to users are different, and the industrial heating can be generally divided into low-parameter heating, medium-parameter heating and high-parameter heating. High-parameter heat supply (generally, heat supply with pressure higher than 4.0MPa and temperature higher than 400 ℃) cannot directly find a proper steam extraction point from a thermal power plant system for direct heat supply because of high temperature and pressure, and only heat source steam with higher pressure and temperature grade can be adopted for direct heat supply after temperature and pressure reduction, so that high energy and low use of energy are often caused, a large amount of heat energy is wasted, and the utilization efficiency of the energy is reduced.
In order to solve the problems, a backpressure machine can be used for replacing the temperature and pressure reduction process of the heat source steam, the heat source steam is introduced into the backpressure machine, the steam (called backpressure machine steam exhaust for short) exhausted by the backpressure machine is used for supplying heat, meanwhile, part of work capacity of the steam is recovered inside the backpressure machine, high-parameter heat supply is realized, energy can be recovered, and the utilization efficiency of energy is improved. However, when a high-parameter heating is performed by using a back-pressure machine, the steam discharged from the back-pressure machine has difficulty in meeting the parameter requirements of the high-parameter heating, such as the pressure and temperature requirements of the steam required by a user. That is, although the use of a back pressure machine can reduce the waste of energy, it cannot meet the requirement of high-parameter heat supply.
Disclosure of Invention
The invention provides a heating system and a heating method, which can be used for solving the problem that the heating requirement of high parameter cannot be met by adopting a back pressure machine in the prior art.
The embodiment of the invention provides a heating system, which comprises: a heat source steam pipeline, an inlet parameter adjusting valve and a back press;
the inlet of the back pressure machine is communicated with the heat source steam pipeline through the inlet parameter adjusting valve, and the inlet parameter adjusting valve is used for adjusting steam parameters at the inlet of the back pressure machine.
Optionally, in an embodiment, the system further comprises a parameter control unit connected to the outlet of the back press, the parameter control unit being configured to adjust an exhaust parameter of the back press.
Optionally, in one embodiment, the parameter control unit comprises a first pressure reduction control device and a first temperature reduction control device, and the first temperature reduction control device is connected with the outlet of the back press through the first pressure reduction control device.
Optionally, in one embodiment, the system further comprises an inlet shutoff valve, a check valve and a power generation device,
the inlet parameter regulating valve is connected with the heat source steam pipeline through the inlet stop valve;
the check valve is connected with an outlet of the back press through the parameter control unit;
the power generation device is connected with the back pressure machine and used for converting the energy recovered by the back pressure machine into electric energy.
Optionally, in an embodiment, the system further includes a backup heating unit in communication with the heat source steam pipe, the backup heating unit includes a second pressure reduction control device and a second temperature reduction control device, and the second temperature reduction control device is connected to the heat source steam pipe through the second pressure reduction control device.
Optionally, in one embodiment, the system further comprises a heat supply header connected to the outlet of the back press and the backup heat supply unit.
The embodiment of the invention also provides a method for supplying heat based on any system provided by the application, which comprises the following steps:
calculating a target parameter of steam at an inlet of the backpressure machine when the steam discharge parameter of the backpressure machine is matched with the parameter of the steam required by the user according to the parameter of the heat source steam, the parameter of the steam required by the user and the characteristic parameter of the backpressure machine;
and adjusting an inlet parameter adjusting valve to adjust the steam parameter entering the back press from the heat source steam pipeline to the target parameter.
Optionally, in one embodiment, the parameter of the heat source steam comprises a first pressure P1And a first temperature t1The parameter of the steam required by the user comprises a second pressure P2And a second temperature t2If the characteristic parameter of the back press includes an efficiency η of the back press, calculating a target parameter of steam at an inlet of the back press when an exhaust steam parameter of the back press is matched with a parameter of steam required by a user according to the parameter of the heat source steam, the parameter of the steam required by the user and the characteristic parameter of the back press, including:
based on the first pressure P1And the first temperature t1Determining a first enthalpy value H of the heat source steam1；
Based on the second pressure P2And said second temperature t2Determining a second enthalpy value H of the steam required by the user2；
According to the first enthalpy value H1Determining a target enthalpy value H of steam at the inlet of said back pressure machinem；
According to the second enthalpy value H2The target enthalpy value HmEfficiency η of the back press and the second pressure P2Calculating the exhaust steam pressure of the back press and the second pressure P2Matching, and when the exhaust steam of the backpressure machine is matched with the second temperature, the target entropy S of the steam at the inlet of the backpressure machinem；
According to the target enthalpy value HmAnd the target entropy value SmCalculating the exhaust steam pressure of the back press and the second pressure P2Matching, and the steam discharge of the back press and the second temperatureTiming, target pressure P of steam at inlet of back pressure machinem；
Adjusting the inlet parameter adjusting valve to adjust the steam parameter entering the back press from the heat source steam pipeline to the target parameter, including: adjusting the inlet parameter adjusting valve to adjust the steam pressure entering the back press from the heat source steam pipeline to the target pressure Pm。
Optionally, in one embodiment, the second enthalpy value H is a function of the first enthalpy value H2The target enthalpy value HmEfficiency η of the back press and the second pressure P2Calculating the exhaust steam pressure of the back press and the second pressure P2Matching, and when the exhaust steam of the backpressure machine is matched with the second temperature, the target entropy S of the steam at the inlet of the backpressure machinemSpecifically, the formula is as follows:
Sm＝f2(P2，[η×Hm-(Hm-H2)]/η)，
wherein f is2A function of entropy values is calculated for the steam from the pressure values and enthalpy values.
Optionally, in one embodiment, the target enthalpy value HmEqual to said first enthalpy value H1。
The invention has the following beneficial effects:
the embodiment of the application provides a heating system and a heating method, wherein the system comprises: a heat source steam pipeline, an inlet parameter adjusting valve and a back press; the inlet of the back pressure machine is communicated with the heat source steam pipeline through the inlet parameter adjusting valve, and the inlet parameter adjusting valve is used for adjusting steam parameters at the inlet of the back pressure machine. When the steam required by the user is high-parameter heat supply steam, the inlet parameter adjusting valve at the inlet of the back pressure machine can be adjusted, so that the parameter of the steam at the inlet of the back pressure machine is adjusted, namely the parameter of the steam about to enter the back pressure machine is adjusted, and the steam discharge parameter of the back pressure machine can reach the parameter of the steam required by the user.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on the drawings without creative efforts. In the drawings:
fig. 1 is a schematic structural diagram of a heating system according to an embodiment of the present application;
fig. 2 is a schematic structural diagram of another heating system provided in the embodiment of the present application;
fig. 3 is a schematic structural diagram of another heating system provided in the embodiment of the present application;
FIG. 4 is a schematic flow chart of a heating method according to an embodiment of the present application;
FIG. 5 is a schematic flow chart of another heating method provided in the embodiments of the present application;
fig. 6 is a schematic diagram of a gas expansion work-producing path in a back-pressure machine according to an embodiment of the present disclosure.
Reference numerals:
10-a heating system; 101-heat source steam pipeline; 102-inlet parameter regulating valve; 103-back press; 104-parameter control unit; 1041-a first reduced-pressure control device; 1042 — a first desuperheating control device; 105-a heating header; 106-inlet shutoff valve; 107-check valve; 108-a standby heating unit; 1081-a second pressure reduction control device; 1082-a second desuperheating control device; 109-heating regulating valve.
Detailed Description
In order to make the objects, technical solutions and advantages of the present application more apparent, the technical solutions of the present application will be described in detail and completely with reference to the following specific embodiments of the present application and the accompanying drawings. It should be apparent that the described embodiments are only some of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.
The features of the terms first and second in the description and in the claims of the present application may explicitly or implicitly include one or more of such features. In the description of the present invention, "a plurality" means two or more unless otherwise specified. In addition, "and/or" in the specification and claims means at least one of connected objects, a character "/" generally means that a preceding and succeeding related objects are in an "or" relationship.
In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the invention and to simplify the description, and are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and are therefore not to be considered limiting of the invention.
In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.
As described in the background, in industrial processes, heat energy is one of the most important forms of energy utilization, and industrial heating varies according to process requirements, and heating steam parameters vary. High-parameter heat supply cannot directly find a proper steam extraction point from a thermal power plant system because the temperature and the pressure are high, and heat supply can be performed only by directly reducing the temperature and the pressure by adopting heat source steam with higher parameters. Wherein, the process of reducing temperature and pressure can directly consume a large amount of heat energy, thereby reducing the utilization efficiency of energy and increasing the heat supply cost of a thermal power plant.
In order to improve the utilization efficiency of energy, the back pressure machine can be used for replacing the temperature and pressure reduction process of the heat source steam, and the exhausted steam of the back pressure machine is used for supplying heat. When the temperature and the pressure of the heat source steam are reduced, the backpressure machine can recover the work capacity of the steam to convert the work capacity into electric energy, and the energy is recycled. However, when the steam expands in the back pressure machine to do work, the pressure and the temperature of the steam are both reduced, but the pressure and the temperature of the steam are not independent of each other, and are related to each other. It will be appreciated that when the backpressure machine exhaust pressure falls to a certain value, the exhaust temperature will fall to a value correlated to the exhaust pressure; when the exhaust temperature drops to a certain value, the exhaust pressure drops to a value that is correlated with the exhaust temperature. Of course, the correlation between the exhaust steam pressure and the exhaust steam temperature of the back pressure machine is also affected by the efficiency of the back pressure machine, and under the condition that the efficiency of the back pressure machine is different, when the exhaust steam pressure is reduced to a certain value, the value to which the exhaust steam temperature is reduced may also be different, and similarly, when the exhaust steam temperature is reduced to a certain value, the value to which the exhaust steam pressure is reduced may also be different. For example, table 1 shows calculated analyses of backpressure exhaust pressure and exhaust temperature:
TABLE 1 calculation analysis of exhaust pressure and exhaust temperature of back pressure machine
| Item | Unit of | Working condition 1 | Working condition 2 | Working condition 3 | Working condition 4 |
| Heat source steam pressure | MPa | 16.67 | 16.67 | 16.67 | 16.67 |
| Temperature of heat source steam | ℃ | 538 | 538 | 538 | 538 |
| Exhaust pressure of back pressure machine | MPa | 4.0 | 4.0 | 5.9 | 6.17 |
| Exhaust temperature of back pressure machine | ℃ | 357.30 | 325.48 | 400 | 400 |
| Efficiency of back press | ％ | 70 | 90 | 70 | 90 |
Table 1 lists four operating conditions, in which the pressure and temperature of the heat source steam introduced into the back press are the same, the pressure is 16.67MPa, the temperature is 538 ℃, the pressure of the steam required by the user (the heat supply steam required by the user) is 4.0MPa, and the temperature is 400 ℃. The efficiency of the back press in the working condition 1 and the industrial control 3 is 70%, and if the steam exhaust pressure of the back press meets the pressure 4.0MPa required by a user, the actual steam exhaust temperature of the back press is reduced to 357.3 ℃ and is lower than the steam temperature required by the user by 400 ℃; and if the steam exhaust temperature of the back press is required to meet 400 ℃, the actual exhaust pressure of the back press is reduced to 5.9MPa, which is higher than the steam pressure required by a user by 4.0 MPa. The efficiency of the back press in the working condition 2 and the working condition 4 is 90%, and if the steam exhaust pressure of the back press meets the steam pressure 4.0MPa required by a user, the actual steam exhaust temperature of the back press is reduced to 325.48 ℃ and is lower than the steam temperature 400 ℃ required by the user; and if the steam exhaust temperature of the back press is required to meet 400 ℃, the actual exhaust pressure of the back press is reduced to 6.17MPa, which is higher than the steam pressure required by a user by 4.0 MPa.
From the above, the pressure and the temperature of the steam required by the user are often independent from each other, and the exhaust pressure and the exhaust temperature of the back pressure machine have a correlation relationship, so that the exhaust pressure and the exhaust temperature of the back pressure machine are difficult to meet the pressure and the temperature of the heating steam required by the user at the same time.
In order to solve the problem that the exhaust pressure and the exhaust temperature of the backpressure machine are difficult to meet the pressure and the temperature of steam required by a user at the same time, the application provides a heat supply system 10, as shown in fig. 1, wherein the system 10 comprises a heat source steam pipeline 101, an inlet parameter regulating valve 102 and a backpressure machine 103; the inlet of the back press 103 is communicated with the heat source steam pipeline 101 through the inlet parameter regulating valve 102, and the inlet parameter regulating valve 102 is used for regulating the steam parameter at the inlet of the back press 103.
Wherein the heat source steam pipeline may be in communication with an extraction point in the thermal power plant system to introduce steam, i.e. heat source steam (indicated as G in fig. 1), having a parameter higher than that of the steam required by the user into the back press 103. Further, the steam parameters at the inlet of the back press 103 can be adjusted by the inlet parameter adjusting valve 102; for example, the inlet parameter regulating valve 102 is adjusted to change the pressure of the steam at the inlet of the back press 103, wherein adjusting the inlet parameter regulating valve 102 may be adjusting the degree of opening of the valve. The exhaust steam of the back press 103 can be used directly for supplying heat to the user (indicated by U in fig. 1).
The embodiment of the application can be through the entry parameter control valve right before heat source steam gets into the backpressure machine by providing a heating system with entry parameter control valve the parameter of heat source steam is preset for steam after the preset gets into the backpressure machine and does work the steam extraction parameter after can satisfy the required steam parameter requirement of user, for example steam extraction pressure and steam extraction temperature satisfy the pressure and the temperature requirement of the required steam of user simultaneously.
In order to further adjust the steam discharge parameters of the back press so that the steam discharge parameters of the back press are exactly matched with the steam parameters required by the user, in an embodiment, the heat supply system 10 provided in the embodiment of the present application further includes a parameter control unit 104 connected to an outlet of the back press 103, as shown in fig. 2, where the parameter control unit 104 is configured to adjust the steam discharge parameters of the back press 103.
The parameter control unit 104 includes a first pressure reduction control device 1041 and a first temperature reduction control device 1042, and the first temperature reduction control device 1042 is connected to the outlet of the back press 103 through the first pressure reduction control device 1041. The first decompression control means 1041 may be a regulating valve, and decompresses the exhaust steam of the back pressure machine 103 to different degrees by adjusting the opening degree of the regulating valve. The first desuperheating control device 1042 may be a desuperheating water system passing through a first desuperheating water (indicated by letter J in FIG. 2)1Shown) to desuperheat the exhaust from the backpressure machine 103.
In practical application, in order to stably supply heat to the exhaust steam of the back pressure machine 103, a heat supply header 105 may be further provided to be connected to an outlet of the back pressure machine 103, and the exhaust steam of the back pressure machine 103 enters the heat supply header 105 to supply energy to a user. The heating header 105 may function to buffer the exhaust of the backpressure unit 103 so that the pressure and temperature of the steam supplied to the user is stable. In the case of not providing the parameter control unit 104, the heat supply header 105 may be directly connected to the outlet of the back pressure machine 103, in the case of providing the parameter control unit 104, the heat supply header 105 may be provided after the parameter control unit 104, and the heat supply header 105 is connected to the outlet of the back pressure machine 103 through the parameter control unit 104, as shown in fig. 2, at this time, the exhaust steam of the back pressure machine 103 enters the heat supply header 105 after being adjusted by the parameter control unit 104, and then supplies heat to the user through the heat supply header 105.
Further, as shown in fig. 2, the heating system 10 provided by the embodiment of the present application may further include an inlet shutoff valve 106, a check valve 107, and a power generation device (not shown in the figure), wherein the inlet parameter adjusting valve 102 is connected to the heat source steam pipeline 101 through the inlet shutoff valve 106; the check valve 107 is connected with the outlet of the back press 103 through the parameter control unit 104; the power generation device is connected with the back pressure machine. The inlet shutoff valve 106 is used for adjusting the opening and closing of the heating system 10, that is, the inlet shutoff valve 106 is opened, the heat source steam supplies heat through the system 10, and the inlet shutoff valve 106 is closed, so that the heat source steam cannot enter the system 10. The check valve 107 is used to prevent steam from flowing backwards, for example, steam in the heating header 105 from flowing backwards to the parameter control unit 104 and the back pressure machine 103. The power generation device is used for converting the energy recovered by the back press 103 into electric energy.
In addition, in order to prevent the heat supply system 10 from failing to supply heat due to a fault, a standby heat supply line may be incorporated therein, so as to realize emergency heat supply and improve the reliability of heat supply under the conditions of a fault in the heat supply line of the back pressure machine, the start-up stage of the back pressure machine, and the like. Thus, in one embodiment, the system 10 further comprises a backup heat supply unit 108 in communication with the heat source steam pipeline 101, as shown in FIG. 3, the backup heat supply unit 108 comprising a second reduced pressure control device 1081 and a second desuperheating control device 1082, the second desuperheating control device 1082 communicating with the second reduced pressure control device 1081 via the second reduced pressure control device 1081The heat source steam pipe 101 is connected. The second decompression control means 1081 may be a control valve, and the heat source steam may be decompressed to different degrees by adjusting the opening degree of the control valve. The second desuperheating control device 1082 may be a desuperheating water system, passing a second desuperheating water (indicated by letter J in FIG. 3)2Indicating) cooling the heat source vapor. Thus, when the system (backpressure machine heating line) in fig. 2 fails, heat can be supplied through the heating line where the standby heating unit 108 in fig. 3 is located, and the reliability of heat supply is enhanced.
In one embodiment, the heating system 10 provided by the present application may further include a heating regulating valve 109, as shown in fig. 3, and the standby heating unit 108 is connected to the heat source steam pipe 101 through the heating regulating valve 109. The heating regulating valve 109 is used for opening or closing the heating route including the heating unit 108 in fig. 3.
In practice, the steam conditioned by the standby heating unit 108 may also be passed into the heating header 105 to stabilize the pressure and temperature of the steam supplied to the user. In a preferred manner, as shown in fig. 3, one and the same heating header 105 is connected to the outlet of the back press 103 and to the standby heating unit 108. That is, both the steam exhausted from the back press 103 and the steam conditioned by the standby heating unit 108 may be introduced into the heating header 105.
The embodiment of the application also provides a method for supplying heat based on any heat supply system provided by the application, and the method comprises the following steps:
And 202, adjusting an inlet parameter adjusting valve, and adjusting the steam parameters entering the back press from the heat source steam pipeline to the target parameters.
Wherein the parameter of the heat source steam comprises a first pressure P1And a first temperature t1The parameter of the steam required by the user comprisesTwo pressures P2And a second temperature t2If the characteristic parameter of the back press includes an efficiency η of the back press, the step 201 specifically includes:
2011, based on the first pressure P1And the first temperature t1Determining a first enthalpy value H of the heat source steam1；
2012, based on the second pressure P2And said second temperature t2Determining a second enthalpy value H of the steam required by the user2；
Step 2014, according to the second enthalpy value H2The target enthalpy value HmEfficiency η of the back press and the second pressure P2Calculating the exhaust steam pressure of the back press and the second pressure P2Matching, and when the exhaust steam of the backpressure machine is matched with the second temperature, the target entropy S of the steam at the inlet of the backpressure machinem；
Adjusting the inlet parameter adjusting valve to adjust the steam parameter entering the back press from the heat source steam pipeline to the target parameter, including: adjusting the inlet parameter adjusting valve to adjust the steam pressure entering the back press from the heat source steam pipeline to the target pressure Pm。
The process of calculating the target parameter of the steam at the inlet of the back press from step 2011 to step 2015 is described in detail as follows:
the heating system 10 provided in the embodiment of the present application, after adding the inlet parameter adjusting valve 102, pre-adjusts the heat source steam entering the back press 103 through the inlet parameter adjusting valve 102, so that the steam expansion work path in the back press 103 is as the path ABC in fig. 6. The point B is the working point of steam at the inlet of the back pressure machine, namely the working point of steam after the inlet parameter regulating valve 102 pre-regulates the heat source steam entering the back pressure machine 103, the point C is the working point of heat supply steam required by a user, the point A is the working point of the heat source steam which is not regulated, the path AC is a path for directly introducing the heat source steam (which is not regulated) into the back pressure machine to do work through expansion, the path BD is an isentropic expansion line, and the path DC is an exhaust pressure isobar.
The operating point B is very critical, the parameter of the point B (the target parameter of the steam at the inlet of the backpressure machine) is obtained through calculation, and the inlet parameter regulating valve is regulated according to the parameter of the point B, so that the expansion path of the steam in the backpressure machine can meet the expansion path ABC in the figure 6, and the steam exhaust of the backpressure machine can meet the heat supply steam parameter required by a user. The B point parameter can be calculated by the following steps:
1. the steam pressure at the working point A is the first pressure P1At a first temperature t1According to said first pressure P1And the first temperature t1The first enthalpy value H1 of the steam at the A working point can be calculated;
H1＝f1(P1，t1) (1)
wherein H1Is the steam enthalpy value of the heat source steam, kJ/kg; p1The steam pressure of the heat source steam is MPa; t is t1The steam temperature of the heat source steam is DEG C; f. of1A function for calculating a steam enthalpy from the steam pressure and temperature; or by function f1Calculate H1Can be directly dependent on the pressure P1And temperature t1The corresponding enthalpy value is found in the water vapor enthalpy entropy diagram.
2. The steam pressure at the C working point is a second pressure P2At a second temperature t2According to said second pressure P2And said second temperature t2The second enthalpy value H of the steam at the C working point can be calculated2；
H2＝f1(P2，t2) (2)
Wherein the content of the first and second substances,H2the enthalpy value of the steam required by the user is kJ/kg; p2The steam pressure of the steam required by the user is MPa; t is t1The steam temperature, DEG C, of the steam required by the user; f. of1A function for calculating a steam enthalpy from the steam pressure and temperature; or by function f1Calculate H2Can be directly dependent on the pressure P2And temperature t2The corresponding enthalpy value is found in the water vapor enthalpy entropy diagram.
3. The process from the working point A to the working point B is a throttling process, and the steam enthalpy value in the process is equal, so that the enthalpy value of the working point B, namely the target enthalpy value HmComprises the following steps:
Hm＝H1 (3)
wherein HmkJ/kg, the steam enthalpy of the steam at the inlet of the back-pressure machine.
4. The expansion from the working condition point B to the working condition point C is determined by the performance of the back pressure machine, when the efficiency of the back pressure machine is eta, the enthalpy value of the isentropic expansion point D of the point B can be calculated when the exhaust steam pressure of the back pressure machine meets the pressure of steam required by a user:
H3＝[η×Hm-(Hm-H2)]/η (4)
wherein H3Under the condition that the exhaust steam pressure of the back press meets the steam pressure required by a user, the isentropic steam enthalpy value of the point B is kJ/kg; η is the back pressure efficiency.
5. Enthalpy value H from point D3And the pressure P of the steam required by the user2The entropy value of the D point can be determined;
S3＝f2(P2，H3) (5)
wherein S is3The steam entropy value of the D point is kJ/(kg. ℃); f. of2A function for calculating an entropy value from the steam pressure and the enthalpy value.
6. Because the process from point B to point D is an isentropic expansion process, the entropy values of the two working points are equal, so that the entropy value (the target entropy value of steam at the inlet of the back pressure machine) of point B can be obtained as follows:
Sm＝S3 (6)
the pressure at point B (target pressure of steam at the inlet of the back-pressure machine) can then be determined as:
Pm＝fshp(Sm，Hm) (7)
the temperature at point B (target temperature of steam at the inlet of the back-pressure machine) was:
tm＝fsht(Sm，Hm) (8)
wherein S ismThe steam entropy value of the B point is kJ/(kg. ℃); pmThe pressure value at the point B is MPa; t is tmThe temperature value at point B is DEG C; f. ofshpA function for calculating pressure from the enthalpy and entropy values of the steam; f. ofshtA function for calculating temperature based on enthalpy and entropy of the steam.
After the B point parameters (including pressure and temperature parameters) are obtained, the inlet parameter adjusting valve can be adjusted according to the parameters. For example, the inlet parameter regulating valve is adjusted according to the pressure parameter (target pressure of steam at the inlet of the back pressure machine) of the point B obtained by calculation, so that the pressure of the steam entering the back pressure machine meets Pm. So that the steam discharge parameters of the backpressure machine can reach the parameters of steam required by users. In practical application, can also set up pressure sensor in entry governing valve department to the pressure of response steam, can also set up display device and show in order to the pressure of steam, this application does not restrict display device's position, can set up the position that corresponds at entry parameter governing valve, also can incorporate display device into heating system's total control module.
Based on the above algorithm, it can be known that the execution logic of the heat supply method provided by the present application for heat supply is as follows:
setting/inputting the parameters of heat supply steam required by a user, adjusting the parameters of heat source steam, adjusting the performance parameters of the back pressure machine, and adjusting the inlet parameter adjusting valve to enable the parameters of the steam entering the back pressure machine to be target parameters.
The calculation process for calculating the B-point operating condition parameter value according to the specific value may be exemplified by the following examples, and it should be understood that the following examples do not represent a limitation to the present application:
the steam parameters of the heat source are 16.67MPa, the temperature is 538 ℃, the steam parameters required by a user are 4.0MPa, the temperature is 400 ℃, and the efficiency of the back pressure machine is 80%. The calculation result according to the steps is as follows:
1) determining the steam parameters of the point A of the heat source steam,
the enthalpy-entropy diagram of the water vapor is obtained by 16.67MPa and 538 ℃, and the enthalpy-entropy diagram of the water vapor is as follows:
H1＝3397.2kJ/kg
2) determining steam parameters of a user side C point:
from 4.0MPa, 400 ℃ according to a function f1It can be calculated that:
H2＝3215.71kJ/kg
3) the enthalpy value of the point B is determined,
Hm＝H1＝3397.2kJ/kg
4) determining the enthalpy value of the isentropic expansion point D point of the point B,
the efficiency of the back pressure machine is 80%, and the parameter of the heat supply steam required by the user is that the pressure is 4.0MPa, so that the following parameters can be calculated:
H3＝[0.8×3397.2-(3397.2-3215.71)]/0.8＝3170.34kJ/kg
5) the entropy value of the point D is determined,
enthalpy value H from point D3Pressure P of the heating steam required by the user2And a function f2It can be calculated that:
S3＝6.71kJ/(kg.℃)
6) the other parameters of the point B are determined,
from S3、HmFunction fshpAnd a function fshtThe following can be calculated respectively:
Sm＝S3＝6.71kJ/(kg.℃)
Pm＝8.37MPa
tm＝501.17℃
according to other finally obtained parameters of the point B, the steam pressure entering the back pressure machine is controlled to be 8.37MPa by adjusting the inlet parameter adjusting valve, so that the steam discharge parameters of the back pressure machine almost meet the steam parameter requirements required by users.
If the actual characteristics of the back pressure machine are different from the design values, the steam discharge parameters can be referred to finely adjust the inlet parameters, and the steam discharge parameters can be further finely adjusted by utilizing a parameter control unit arranged at the outlet of the back pressure machine, so that the steam discharge is matched with the steam parameters required by a user.
The system and the method provided by the application not only solve the problem that the high-parameter heating temperature and pressure are difficult to simultaneously match the pressure and the temperature of steam required by a user, but also can recover energy and improve the utilization rate of the energy.
For example: the steam parameter of the heat supply heat source is 16.67MPa, the temperature is 538 ℃, the steam parameter pressure required by a user is 4.0MPa, the temperature is 400 ℃, the heat supply amount is 150t/h, the efficiency of the back pressure machine is 80%, the power generation efficiency of the back pressure machine is 95%, the efficiency of the main power generator is 98%, the exhaust steam of the main system steam turbine is 4.9kPa, and the exhaust steam enthalpy value is calculated according to 2300kJ/kg (in order to simplify the calculation, the mechanical loss of the system is not considered), then the output shaft power of the back pressure machine is:
PtBt＝150×1000/3600×(3397.2-3215.71)＝7564.62kW
the generated power is as follows:
PeBt＝7564.62×95％＝7186.39kW
if the traditional temperature and pressure reduction process is adopted to directly carry out temperature and pressure reduction on heat source steam and then supply heat, the energy recovery effect is calculated according to the heat source steam parameter pressure of 16.67MPa, the temperature of 538 ℃ and the temperature reduction water pressure of 8MPa and the temperature of 170 ℃, and the result is shown in the following table 2:
TABLE 2 Heat supply numerical analysis for traditional heating system
| Item | Numerical value | Unit of |
| Enthalpy of heat source steam | 3397.26 | kJ/kg |
| Heat source steam flow | 139.82 | t/h |
| Enthalpy of desuperheated water | 723.11 | kJ/kg |
| Flow rate of reduced temperature water | 10.18 | t/h |
| Flow of heating steam | 150.00 | t/h |
As can be seen from the data in Table 2, if the traditional heating method is adopted to supply heat, when the heating load is 150t/h, 139.82t/h of heat source steam is extracted, and the water spraying amount of the desuperheating water is 10.18t/h, then the steam extraction of part of the heat source steam is replaced by the flow of the desuperheating water, so that part of the recovery work can be generated, and the calculation is as follows:
Ptt＝10.18×1000/3600×(3397.2-2300)＝3103.92kW
the power generated by the traditional heat supply mode is as follows:
Pet＝3103.92×98％＝3041.85kW
by comparison, the heating system and the traditional heating system provided by the application have the following recovery power difference values:
△Pe＝PtBt-Ptt＝7186.39-3041.85＝4144.54kW
therefore, the heating system provided by the application can recover more steam work capacity than the traditional heating system.
Therefore, according to the heat supply system and the heat supply method provided by the embodiment of the application, the inlet parameter adjusting valve at the inlet of the backpressure machine is adjusted, and then the parameter of the steam at the inlet of the backpressure machine is adjusted, namely the parameter of the steam which is about to enter the backpressure machine is adjusted, so that the steam exhaust parameter of the backpressure machine can reach the parameter of the steam required by a user, and the problem that the high-parameter heat supply temperature and pressure are difficult to simultaneously match the steam parameter required by the user is solved. Meanwhile, heat is supplied by exhausting steam through the backpressure machine, the traditional temperature and pressure reduction heat supply system is replaced, the acting capacity of recovering steam is improved, and the energy utilization efficiency is improved.
It should also be noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.
Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.
Claims (10)
1. A heating system, characterized in that the system comprises: a heat source steam pipeline, an inlet parameter adjusting valve and a back press;
the inlet of the back pressure machine is communicated with the heat source steam pipeline through the inlet parameter adjusting valve, and the inlet parameter adjusting valve is used for adjusting steam parameters at the inlet of the back pressure machine.
2. The system of claim 1, further comprising a parameter control unit connected to the backpressure machine outlet for adjusting a steam discharge parameter of the backpressure machine.
3. The system of claim 2, wherein the parameter control unit comprises a first pressure reduction control device and a first desuperheating control device, the first desuperheating control device being connected to the outlet of the backpressure machine through the first pressure reduction control device.
4. The system of claim 3, further comprising an inlet shutoff valve, a check valve, and a power generation device,
the inlet parameter regulating valve is connected with the heat source steam pipeline through the inlet stop valve;
the check valve is connected with an outlet of the back press through the parameter control unit;
the power generation device is connected with the back pressure machine and used for converting the energy recovered by the back pressure machine into electric energy.
5. The system of claim 1, further comprising a backup heating unit in communication with the heat source steam line, the backup heating unit including a second pressure reduction control device and a second desuperheating control device, the second desuperheating control device being connected to the heat source steam line through the second pressure reduction control device.
6. The system of claim 5, further comprising a heat supply header connected to an outlet of the backpressure machine and to the backup heat supply unit.
7. A method of providing heat using the system of any one of claims 1-6, the method comprising:
calculating a target parameter of steam at an inlet of the backpressure machine when the steam discharge parameter of the backpressure machine is matched with the parameter of the steam required by the user according to the parameter of the heat source steam, the parameter of the steam required by the user and the characteristic parameter of the backpressure machine;
and adjusting an inlet parameter adjusting valve to adjust the steam parameter entering the back press from the heat source steam pipeline to the target parameter.
8. The method of claim 7, wherein the parameter of the heat source steam comprises a first pressure P1And a first temperature t1The parameter of the steam required by the user comprises a second pressure P2And a second temperature t2If the characteristic parameter of the back press includes an efficiency η of the back press, calculating a target parameter of steam at an inlet of the back press when an exhaust steam parameter of the back press is matched with a parameter of steam required by a user according to the parameter of the heat source steam, the parameter of the steam required by the user and the characteristic parameter of the back press, including:
based on the first pressure P1And the first temperature t1Determining a first enthalpy value H of the heat source steam1；
Based on the second pressure P2And said second temperature t2Determining a second enthalpy value H of the steam required by the user2；
According to the first enthalpy value H1Determining a target enthalpy value H of steam at the inlet of said back pressure machinem；
According to the second enthalpy value H2The target enthalpy value HmEfficiency η of the back press and the second pressure P2Calculating the exhaust steam pressure of the back press and the second pressure P2Matching, and when the exhaust steam of the backpressure machine is matched with the second temperature, the target entropy value of the steam at the inlet of the backpressure machineSm；
According to the target enthalpy value HmAnd the target entropy value SmCalculating the exhaust steam pressure of the back press and the second pressure P2Matching, and when the exhaust steam of the backpressure machine and the second temperature are matched, the target pressure P of the steam at the inlet of the backpressure machinem；
Adjusting the inlet parameter adjusting valve to adjust the steam parameter entering the back press from the heat source steam pipeline to the target parameter, including: adjusting the inlet parameter adjusting valve to adjust the steam pressure entering the back press from the heat source steam pipeline to the target pressure Pm。
9. The method of claim 8, wherein said second enthalpy value H is a function of2The target enthalpy value HmEfficiency η of the back press and the second pressure P2Calculating the exhaust steam pressure of the back press and the second pressure P2Matching, and when the exhaust steam of the backpressure machine is matched with the second temperature, the target entropy S of the steam at the inlet of the backpressure machinemSpecifically, the formula is as follows:
Sm＝f2(P2，[η×Hm-(Hm-H2)]/η)，
wherein f is2A function of entropy values is calculated for the steam from the pressure values and enthalpy values.
10. The method of claim 8, wherein said target enthalpy value HmEqual to said first enthalpy value H1。
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011319758.3A CN112523824B (en) | 2020-11-23 | 2020-11-23 | Method for supplying heat by using heat supply system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011319758.3A CN112523824B (en) | 2020-11-23 | 2020-11-23 | Method for supplying heat by using heat supply system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112523824A true CN112523824A (en) | 2021-03-19 |
| CN112523824B CN112523824B (en) | 2022-12-09 |
Family
ID=74992581
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011319758.3A Active CN112523824B (en) | 2020-11-23 | 2020-11-23 | Method for supplying heat by using heat supply system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112523824B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114000924A (en) * | 2021-09-16 | 2022-02-01 | 国能(福州)热电有限公司 | Cogeneration centralized steam supply system and control method thereof |
Citations (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0486359A (en) * | 1990-07-31 | 1992-03-18 | Toshiba Corp | Output control unit of co-generation plant |
| CN102518483A (en) * | 2011-12-30 | 2012-06-27 | 北京中科华誉能源技术发展有限责任公司 | Modularized steam waste pressure and waste heat power generation and balanced steam and heat supply system |
| US20140208752A1 (en) * | 2011-02-07 | 2014-07-31 | Krishna Moorthy Palanisamy | Method and apparatus of producing and utilizing thermal energy in a combined heat and power plant |
| CN104329128A (en) * | 2014-10-31 | 2015-02-04 | 华电国际电力股份有限公司技术服务中心 | Back pressure machine work application device for supplying discharged steam of steam turbine high-pressure cylinder for industrial steam extracting system |
| CN104405457A (en) * | 2014-11-28 | 2015-03-11 | 中国华能集团公司 | Energy cascade utilization system of back pressure turbine heating |
| CN205477772U (en) * | 2016-03-30 | 2016-08-17 | 西安交通大学 | Temperature and pressure reduction steam -turbine plant |
| CN105888740A (en) * | 2016-01-27 | 2016-08-24 | 华电漯河发电有限公司 | Backpressure turbine and motor single-shaft combined drive connection structure |
| CN107725122A (en) * | 2017-09-12 | 2018-02-23 | 杭州汽轮机股份有限公司 | 9MW mixes temperature and enters vapour control exhaust temperature back pressure turbine and its temperature control method |
| CN207297114U (en) * | 2017-09-19 | 2018-05-01 | 南京电力设备质量性能检验中心 | A kind of high pressure combining heating system based on back pressure machine technology |
| CN209671011U (en) * | 2018-05-23 | 2019-11-22 | 中机国能电力工程有限公司 | One kind is about utilization pressure matcher and back pressure turbine combined unit |
| CN111047168A (en) * | 2019-12-02 | 2020-04-21 | 国网河北省电力有限公司电力科学研究院 | Peak regulation capacity evaluation method after high-back-pressure heat supply reconstruction of heat supply unit |
| CN111058902A (en) * | 2019-11-28 | 2020-04-24 | 云南固废投资有限公司 | Energy-saving system and energy-saving control method based on industrial steam turbine asynchronous power generation |
| CN211648268U (en) * | 2020-02-27 | 2020-10-09 | 西安西热节能技术有限公司 | Water and electricity co-production system for realizing gradient utilization of heat source steam energy |
-
2020
- 2020-11-23 CN CN202011319758.3A patent/CN112523824B/en active Active
Patent Citations (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0486359A (en) * | 1990-07-31 | 1992-03-18 | Toshiba Corp | Output control unit of co-generation plant |
| US20140208752A1 (en) * | 2011-02-07 | 2014-07-31 | Krishna Moorthy Palanisamy | Method and apparatus of producing and utilizing thermal energy in a combined heat and power plant |
| CN102518483A (en) * | 2011-12-30 | 2012-06-27 | 北京中科华誉能源技术发展有限责任公司 | Modularized steam waste pressure and waste heat power generation and balanced steam and heat supply system |
| CN104329128A (en) * | 2014-10-31 | 2015-02-04 | 华电国际电力股份有限公司技术服务中心 | Back pressure machine work application device for supplying discharged steam of steam turbine high-pressure cylinder for industrial steam extracting system |
| CN104405457A (en) * | 2014-11-28 | 2015-03-11 | 中国华能集团公司 | Energy cascade utilization system of back pressure turbine heating |
| CN105888740A (en) * | 2016-01-27 | 2016-08-24 | 华电漯河发电有限公司 | Backpressure turbine and motor single-shaft combined drive connection structure |
| CN205477772U (en) * | 2016-03-30 | 2016-08-17 | 西安交通大学 | Temperature and pressure reduction steam -turbine plant |
| CN107725122A (en) * | 2017-09-12 | 2018-02-23 | 杭州汽轮机股份有限公司 | 9MW mixes temperature and enters vapour control exhaust temperature back pressure turbine and its temperature control method |
| CN207297114U (en) * | 2017-09-19 | 2018-05-01 | 南京电力设备质量性能检验中心 | A kind of high pressure combining heating system based on back pressure machine technology |
| CN209671011U (en) * | 2018-05-23 | 2019-11-22 | 中机国能电力工程有限公司 | One kind is about utilization pressure matcher and back pressure turbine combined unit |
| CN111058902A (en) * | 2019-11-28 | 2020-04-24 | 云南固废投资有限公司 | Energy-saving system and energy-saving control method based on industrial steam turbine asynchronous power generation |
| CN111047168A (en) * | 2019-12-02 | 2020-04-21 | 国网河北省电力有限公司电力科学研究院 | Peak regulation capacity evaluation method after high-back-pressure heat supply reconstruction of heat supply unit |
| CN211648268U (en) * | 2020-02-27 | 2020-10-09 | 西安西热节能技术有限公司 | Water and electricity co-production system for realizing gradient utilization of heat source steam energy |
Non-Patent Citations (3)
| Title |
|---|
| 冯知正等: "600MW机组中压工业供汽方案的研究", 《电力科技与环保》 * |
| 卢洲杰等: "利用汽轮机中压调门调整抽汽的技术分析研究", 《热力透平》 * |
| 施润华: "《船舶汽轮机动力装置》", 31 August 1994, 上海交通大学出版社 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114000924A (en) * | 2021-09-16 | 2022-02-01 | 国能(福州)热电有限公司 | Cogeneration centralized steam supply system and control method thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| CN112523824B (en) | 2022-12-09 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP6587460B2 (en) | Hydrogen production facility and hydrogen production method | |
| US8695347B2 (en) | Power plant | |
| JPH02256803A (en) | Device for generating power actuated by steam and power generating method | |
| CN112523824B (en) | Method for supplying heat by using heat supply system | |
| AU2020232743B2 (en) | Reversible water electrolysis system and operation method thereof | |
| CN103696819A (en) | High pressure and low pressure two-stage industrial steam extraction heat supply device for steam turbine | |
| EP3869599A1 (en) | Reversible water electrolysis system and method for operating same | |
| CN210088818U (en) | System for nuclear power starts electric boiler heat reserve | |
| CN109751652B (en) | High back pressure and heat pump combined heat supply system of 300MW and above grade wet cooling unit | |
| CN206903698U (en) | Back pressure turbine system with attemperator | |
| CN206290974U (en) | A kind of many gas source type binary channels air compressors | |
| CN201715247U (en) | Steam supply system of water feeding pump steam turbine and deaerator in thermal generator set | |
| JP2000110511A (en) | Cogeneration method and its system | |
| CN113250770A (en) | Thermal power generating unit non-external steam source starting system and method | |
| CN208396754U (en) | Steam turbine start stop system and its work system | |
| JP2006063886A (en) | Thermal power plant | |
| CN202510177U (en) | Two-stage power system for recycling afterheat by using screw expander | |
| TWI557981B (en) | Power generation apparatus integrated clp and sofc and operation method thereof | |
| CN220926283U (en) | Byproduct steam recovery system of reducing furnace and polysilicon production line | |
| JP4127541B2 (en) | Power generation / desalination complex plant and operation method thereof | |
| Fomin et al. | Combined-cycle gas turbine plant based on steam-turbine unit and a parallel superimposed gas-turbine plant with waste heat recovery boiler | |
| CN203702276U (en) | Low-pressure steam recycling device | |
| CN218407548U (en) | Ultralow-quality steam recovery device | |
| WO2023223713A1 (en) | Steam generating device, and steam generating method | |
| CN214997843U (en) | Flash steam waste heat power generation system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |