Thermal power generating unit steam turbine exhaust steam waste heat heat supply system and adjusting method thereof

Abstract

The invention relates to the technical field of waste heat supply, in particular to a thermal power generating unit steam turbine exhaust steam waste heat supply system and an adjusting method thereof.The waste heat supply system comprises a steam turbine, a condenser, a cooling tower, an initial station heater, an absorption heat pump, a secondary heat exchange station and a coupling controller; primary network water at an outlet of the absorption heat pump and primary network water at an outlet of a first station heater do not independently enter a secondary heat exchange station for heat exchange and are connected through a coupling controller, reasonable distribution of heat supply network water quantity and steam extraction quantity is carried out between the absorption heat pump and original heating steam extraction, and the input end of a steam turbine is communicated with the output end of a boiler. And heat is supplied between the steam turbine and the first station heater in a heating steam extraction mode. According to the thermal power generating unit steam turbine exhaust steam waste heat heat supply system and the adjusting method thereof, the absorption heat pump and combined heat and power generation coupling heat supply scheme is adopted, full-load operation of the heat pump in the whole heat supply period can be achieved, and the total heat supply amount is reasonably distributed between two heat supply networks through the coupling controller.

Description

Technical Field

[0001] The invention relates to the technical field of waste heat heating, and in particular to a steam turbine exhaust waste heat heating system for a thermal power unit and a regulating method thereof. Background Art

[0002] In recent years, various power companies in my country have taken effective measures and played a positive role in optimizing processes and implementing energy-saving transformation. For example, through process improvement and equipment transformation of existing power plants, the performance of generator sets and related equipment has been greatly improved, and the energy-saving effect has also been made more obvious. Therefore, in the operation of existing power plants, energy-saving transformation has become the focus of existing enterprise management and research, and has also become an urgent problem to be solved. In this case, in response to the problems existing in the operation of steam engines in Shenhua Coal Mine Power Plant and the pressure brought by high energy consumption, the company should take effective measures to strengthen energy-saving transformation to reduce costs and improve the economic benefits of the company.

[0003] Coal-fired power units are one of the important equipment in power plants, and the steam turbine thermal system is one of the most important components of coal-fired power units. Therefore, the steam turbine thermal system is very important for power plants. However, in the actual operation process, the steam turbine thermal system often has problems with inefficient operation and poor energy conversion effect, which affects the normal operation of coal-fired power units and the normal operation of power plant production.

[0004] With the increase of urban heating area, the demand for heating load is also rising, which requires the expansion of heating capacity. Due to the limited heating capacity of power plants, incorporating heat pumps into power plants to expand heating capacity has become a relatively ideal solution. For coupled heating systems, it is not only necessary to study a certain part of the heating system, but also to comprehensively consider all parts of the entire heating system, such as heat users, heating networks, steam turbines and absorption heat pumps. Considering the entire heating period, first of all, the outdoor temperature causes the water temperature of the heating network to change, the heating load changes, which leads to changes in the steam extraction volume of the steam turbine, and the load of the heat pump may also change. Therefore, it is necessary to couple the absorption heat pump with cogeneration for heating. Different from heating with a single heat pump or heating with a heating network heater, the existence of a coupling controller enables the heat to be re-distributed reasonably between the two heating networks. By controlling the water volume and steam extraction volume of the heating network, the heat pump is used first, and then the heating network heater is used for heating, so that the circulating water waste heat of the power plant is maximized.

[0005] Thermal power generation uses the heat generated by fuel to heat water, forming high-temperature and high-pressure superheated steam. The steam then enters the steam turbine along the pipeline and continues to expand and do work, impacting the turbine rotor to rotate at high speed, driving the generator rotor to rotate, and the stator coil cuts the magnetic lines of force, thereby generating electricity. Existing steam turbines only use steam once, and the steam discharged from the steam turbine still has high thermal energy, resulting in a waste of steam heat. Summary of the invention

[0006] The object of the present invention is to provide a thermal power unit steam turbine exhaust waste heat heating system and a regulation method thereof, so as to solve the problems raised in the above background technology.

[0007] To achieve the above-mentioned object, the present invention provides the following technical solutions: a thermal power unit steam turbine exhaust waste heat heating system, the waste heat heating system comprising a steam turbine, a condenser, a cooling tower, a first station heater, an absorption heat pump, a secondary heat exchange station and a coupling controller;

[0008] The primary network water at the outlet of the absorption heat pump and the primary network water at the outlet of the first station heater do not enter the secondary heat exchange station for heat exchange separately, but are connected through a coupling controller, and the absorption heat pump and the original heating extraction steam are reasonably allocated to the heat network water volume and the extraction steam volume;

[0009] The input end of the steam turbine is connected to the output end of the boiler, and the steam turbine and the first-station heater are heated by heating steam extraction. The first-station heater is connected to a deaerator, and the secondary heat exchange station is connected to the heating channel of the heating user.

[0010] Preferably, the absorption heat pump uses a first type lithium bromide absorption heat pump, which uses a high-temperature heat source as a driving heat source, a lithium bromide solution as an absorbent, and water as a refrigerant, and recycles a low-temperature heat source.

[0011] Preferably, the cooling tower includes an arc pipe, a water storage tank, a water tank, a heating pipe, a water supply pipe, a first water pump and a second water pump. The water storage tank and the water tank are connected by an arc pipe, the first water pump, the second water pump and the water tank are connected by a water supply pipe, and the input end of the condenser is connected to the output end of the water storage tank.

[0012] Preferably, when the newly added heating user load is less than the heat pump capacity, the steam extraction amount and the heat network water flow are adjusted by the coupling controller to maintain the two heat network water parameters unchanged, and the excess heat of the heat pump is transported to the original heat network, thereby reducing the heating steam extraction amount.

[0013] Preferably, when the newly added heating user load is greater than the heat pump capacity, the absorption heat pump raises the rated temperature of the heat network return water, and the first station heater increases the heating extraction steam to provide the remaining required heat, and the heat pump outlet water is mixed with the first station heater outlet water to reach the water supply temperature required by the primary network.

[0014] A method for regulating a steam turbine exhaust waste heat heating system of a thermal power unit comprises the following steps:

[0015] S1: Use the quality adjustment method to analyze the indirect heating mode, change the supply and return water temperature of the heating network pipeline, and keep the user's circulating water volume unchanged to maintain the stability of the hydraulic working conditions of the heating user system;

[0016] S2: When all the design parameters are known, the relationship between the supply and return water temperatures of the heating network and the outdoor air temperature can be obtained through the formula. At the corresponding outdoor temperature, the changes in the secondary network supply and return water temperatures in the heating system can be calculated;

[0017] S3: When the outdoor temperature rises, that is, the heat load decreases, the supply and return water temperatures of the heating network decrease, the required steam extraction volume of the heating unit decreases, and the power generation increases. On the contrary, when the outdoor temperature decreases, the steam extraction volume increases, and the power generation decreases accordingly.

[0018] S4: The supply and return water temperatures of the heating network are relative to the heat load ratio. As the outdoor temperature increases, the supply and return water temperatures of the primary and secondary networks decrease accordingly, and the supply and return water temperature difference also decreases. The outdoor temperature is high, and the corresponding supply and return water temperatures decrease. At this time, the heat load decreases. If the heat pump and cogeneration are used for heating separately, the heat pump can only operate at full load in the middle of the heating period, and a large capacity will be idle in the early and late stages.

[0019] Preferably, the inlet and outlet water temperature limits of the absorption heat pump set the primary network supply and return water temperatures to 85 / 50°C.

[0020] Preferably, the supply and return water temperatures in the low-temperature hot water floor radiant heating system should be determined after calculation, and the supply water temperature should not be greater than 60°C. The supply water temperature in civil buildings should be 35-50°C, and the difference between the supply and return water temperatures should not exceed 10°C. The secondary network supply and return water temperatures are 48 / 40°C.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] 1. The steam turbine exhaust waste heat heating system of the thermal power unit and its adjustment method adopt an absorption heat pump and cogeneration coupling heating scheme, which can realize the full load operation of the heat pump during the entire heating period. The total heat supply is reasonably distributed between the two heating networks through the coupling controller, and the heat pump is used first for heating, and then the heater is used, which is achieved by adjusting the steam extraction amount.

[0023] 2. The thermal power unit steam turbine exhaust waste heat heating system and its regulation method use heat pump technology to recover waste heat from thermal power plants, making full use of the waste heat of flue gas and circulating cooling water in thermal power plants, and realizing cogeneration of heat and power, so that thermal power plants can achieve heating purposes while generating electricity by burning coal or gas, thereby improving the energy utilization efficiency of thermal power plants, greatly reducing the consumption of non-renewable energy, and achieving the ultimate goal of energy conservation and emission reduction. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative labor.

[0025] Figure 1 It is a heating flow chart of the absorption heat pump and cogeneration coupling of the present invention;

[0026] Figure 2 This is a schematic diagram of the first type of absorption heat pump process of the present invention. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0029] See also Figure 1-Figure 2 , the present invention provides a technical solution: a waste heat heating system for steam turbine exhaust of a thermal power unit, the waste heat heating system comprising a steam turbine, a condenser, a cooling tower, a first station heater, an absorption heat pump, a secondary heat exchange station and a coupling controller;

[0030] The primary network water at the outlet of the absorption heat pump and the primary network water at the outlet of the first station heater do not enter the secondary heat exchange station for heat exchange separately. They are connected through a coupling controller to reasonably distribute the heat network water and steam extraction between the absorption heat pump and the original heating extraction steam.

[0031] The input end of the steam turbine is connected to the output end of the boiler. The steam turbine and the first-station heater are heated by heating extraction. The first-station heater is connected to a deaerator, and the secondary heat exchange station is connected to the heating channel of the heating user.

[0032] The absorption heat pump uses the first type of lithium bromide absorption heat pump, which uses a high-temperature heat source as a driving heat source, a lithium bromide solution as an absorbent, and water as a refrigerant, and recycles the low-temperature heat source.

[0033] The dilute lithium bromide solution coming out of the absorber is pressurized by the solution pump and flows through the heat exchanger, where it is heated by the high-temperature concentrated lithium bromide solution coming out of the generator. It then enters the generator, where it is heated to boiling by the driven steam. The water in it gradually evaporates, and the concentration of the dilute lithium bromide solution continues to increase to become a concentrated solution. The refrigerant steam is sent to the condenser.

[0034] The refrigerant vapor from the generator is separated from the mixed droplets by the liquid baffle plate and then enters the condenser, where it exchanges heat with the heating water supply and condenses into refrigerant water. The refrigerant water accumulated in the lower part of the condenser is sprayed into the evaporator through the U-shaped liquid seal, which can prevent the steam in the condenser from directly entering the evaporator.

[0035] After the refrigerant water enters the evaporator, due to the pressure reduction, part of the low-pressure refrigerant steam is first flashed out. Since the evaporator uses a spray heat exchanger, the spray volume is many times larger than the evaporation volume, so most of the refrigerant water gathers in the water pan of the evaporator, and then is pumped into the spray pipe of the evaporator after the refrigerant water pump boosts the pressure, and then sprayed onto the outer surface of the tube cluster through the nozzle. After absorbing the heat of the low-temperature heat source water flowing through the tube cluster, it evaporates into low-pressure refrigerant steam. The low-pressure refrigerant steam enters the absorber after the mixed droplets are separated by the liquid baffle plate, and is absorbed by the lithium bromide concentrated solution evenly sprayed on the surface of the absorber tube cluster to form a dilute lithium bromide solution. The dilute solution gathers at the bottom of the absorber and is then pumped to the generator by the solution pump.

[0036] The heat pump consists of the main components such as evaporator, absorber, regenerator, condenser and heat exchanger, as well as auxiliary parts such as exhaust device and shielding pump. The exhaust device removes the non-condensable gas in the heat pump and keeps the heat pump in a high vacuum state. In order to improve the system circulation efficiency, a solution heat exchanger is generally set.

[0037] The evaporator utilizes the latent heat of evaporation of the refrigerant dispersed on the outer surface of the tube to absorb heat from a low-temperature heat source such as heat source water flowing in the tube.

[0038] The concentrated lithium bromide solution concentrated by the regenerator in the absorber is spread outside the absorber tube. The concentrated lithium bromide solution absorbs the refrigerant vapor from the evaporator, uses the absorption heat to heat the warm water, and the lithium bromide becomes a dilute solution.

[0039] The regenerator absorbs the refrigerant vapor with an absorber, and the lithium bromide solution with reduced absorption capacity is pumped to the regenerator with a solution pump. In the regenerator, the dilute solution of concentrated lithium bromide is heated by the driving heat source flowing in the tube, and the refrigerant vapor is discharged to become a concentrated solution with restored absorption capacity, which is then sent back to the absorber.

[0040] The refrigerant vapor generated in the regenerator of the condenser is sent to the condenser for condensation, heating the hot water flowing in the condenser tubes to become refrigerant liquid, and returns to the evaporator.

[0041] The solution heat exchanger, in the regenerator, raises the dilute lithium bromide solution from the absorber to the saturation temperature, so that it produces refrigerant vapor, and the dilute solution enters the regenerator. The higher the temperature rises, the less the necessary heating amount (i.e., the driving heat source amount) in the regenerator, and the higher the cycle efficiency. For this purpose, it is generally necessary to set up a solution heat exchanger for heat exchange between the dilute lithium bromide solution from the absorber and the concentrated solution from the regenerator to increase the temperature of the dilute lithium bromide solution entering the regenerator.

[0042] The cooling tower includes an arc pipe, a water storage tank, a water storage tank, a heating pipe, a water supply pipe, a first water pump and a second water pump. The water storage tanks are connected to each other through the arc pipe, the first water pump, the second water pump and the water storage tank are connected through the water supply pipe, and the input end of the condenser is connected to the output end of the water storage tank.

[0043] Steam turbine units have many steam traps, and valve leakage often occurs, resulting in system heat loss. Leakage of high-temperature and high-pressure pipeline steam traps has a great impact on the economy of the system. The main reason for the leakage of system steam traps is the large pressure difference before and after the valves, poor working conditions, and steam flushing when the unit is started and stopped. Different reasons cause different internal leakages, and have different effects on the system. The leakage problem of steam turbine valves can be solved by regularly checking the various dredging and steam trap valves of the unit, and repairing and replacing the leaking valves in time. In order to improve the energy efficiency of the system, the ventilation valves can be appropriately reduced.

[0044] The variable operating conditions of the absorption heat pump and cogeneration coupled heating system mainly involve three parts, namely the parameter changes on the heat network steam turbine and heat pump side. To calculate the variable operating conditions of the system during the entire heating period, it is necessary to first calculate the heat network to clarify the process of the heating load changing with the change of outdoor temperature, which is the basis of thermal calculation. By adjusting the circulating water volume, the turbine back pressure is maintained unchanged. When the steam inlet parameters remain unchanged, the variable operating conditions of the steam turbine are only related to the steam extraction volume of the unit. The steam extraction volume of the unit includes the steam extraction volume of the heat network heater and the steam extraction volume of the heat pump, so they need to be calculated separately. The scheme adopts the priority use of heat pumps for heating. When the heat pump is insufficient, the steam extraction of the heat network heater is used for supplementary heating. Maintain the steam extraction pressure unchanged and ignore the influence of the inlet water temperature of the heat pump low-temperature heat source on the heat pump performance coefficient.

[0045] During the operation of the heating system, the heating load variation is mainly considered to adjust the heating supply. During the entire heating period, when the heating system provides heating to users, under any outdoor meteorological conditions, it should ensure that the indoor temperature of the building meets the user's requirements and is maintained within a limited range. To achieve this standard, not only a reasonable design is required, but also the heating supply of the building must be adjusted according to the changes in the user's heat load caused by changes in meteorological conditions, so as to achieve a balance between heat supply and demand and meet the user's demand for indoor temperature. Therefore, in the heating system, the law of heating load changes with outdoor temperature is usually used as the basis for heating regulation.

[0046] Since most large thermal power plants are built in the suburbs, most thermal power plants use indirect heating to provide heat to users. The indirect heating network is divided into primary heating network and secondary heating network. The primary heating network transfers the heat provided by the power plant to the thermal power station, and the thermal power station transfers the heat from the secondary network to the secondary network, which is then transferred to the user side.

[0047] A method for regulating a steam turbine exhaust waste heat heating system of a thermal power unit comprises the following steps:

[0048] S1: Use the quality adjustment method to analyze the indirect heating mode, change the supply and return water temperature of the heating network pipeline, and keep the user's circulating water volume unchanged to maintain the stability of the hydraulic working conditions of the heating user system;

[0049] S2: When all the design parameters are known, the relationship between the supply and return water temperatures of the heating network and the outdoor air temperature can be obtained through the formula. At the corresponding outdoor temperature, the changes in the secondary network supply and return water temperatures in the heating system can be calculated;

[0050] S3: When the outdoor temperature rises, that is, the heat load decreases, the supply and return water temperatures of the heating network decrease, the required steam extraction volume of the heating unit decreases, and the power generation increases. On the contrary, when the outdoor temperature decreases, the steam extraction volume increases, and the power generation decreases accordingly.

[0051] S4: The supply and return water temperatures of the heating network are relative to the heat load ratio. As the outdoor temperature increases, the supply and return water temperatures of the primary and secondary networks decrease accordingly, and the supply and return water temperature difference also decreases. The outdoor temperature is high, and the corresponding supply and return water temperatures decrease. At this time, the heat load decreases. If the heat pump and cogeneration are used for heating separately, the heat pump can only operate at full load in the middle of the heating period, and a large capacity will be idle in the early and late stages.

[0052] The inlet and outlet water temperature limits of the absorption heat pump set the primary network supply and return water temperatures at 85 / 50°C. The supply and return water temperatures in the low-temperature hot water floor radiant heating system should be determined after calculation, and the supply water temperature should not be greater than 60°C. The supply water temperature in civil buildings should be 35-50°C, and the difference between the supply and return water temperatures should not exceed 10°C. The secondary network supply and return water temperatures are 48 / 40°C.

[0053] When all design parameters are known, the relationship between the supply and return water temperatures of the heating network and the outdoor air temperature can be obtained through the formula. The calculation method of the supply and return water temperatures of the secondary heating network system when the quality adjustment temperature changes is as follows:

[0054]

[0055] Where: t g ,t h The actual supply and return water temperature of the secondary network at a certain outdoor temperature;

[0056] t n Calculate temperatures for indoor heating;

[0057] Δt s `=0.5(t` g +t` h +2t n ) is the average calculated temperature difference for the user's radiator design;

[0058] Δt t `=t` g -t` h Design the supply and return water temperature difference for the user end;

[0059] The corresponding t w The ratio of heating compliance under the condition to heating design heat load, i.e. relative heating compliance;

[0060] t w is the outdoor temperature;

[0061] b is the heat transfer index of the user's radiator, which is taken as 0.3 here;

[0062] is the relative flow ratio of the secondary heating network, and the quality adjustment is 1;

[0063] t` g ,t` h Design supply and return water temperatures for the secondary heating network.

[0064] According to the above formula, the change of the secondary network supply and return water temperature in the heating system can be calculated at the corresponding outdoor temperature. The quality regulation method has simple equipment and convenient control, so it is widely used. When the outdoor temperature rises, that is, the heat load decreases, the supply and return water temperature of the heating network decreases, the required steam extraction of the heating unit decreases, and the power generation increases. On the contrary, when the outdoor temperature decreases, the steam extraction increases, and the power generation decreases accordingly.

[0065] The basic formula for primary heat network quality regulation is:

[0066]

[0067] Where: τ1, τ2 are the actual supply and return water temperatures of the primary network at a certain outdoor temperature;

[0068] τ1` and τ`2 are the design supply and return water temperatures of the primary network;

[0069] is the logarithmic mean temperature difference of the heat exchanger under design conditions.

[0070] At a certain outdoor temperature t w When Δt`, τ1`, τ`2 are known values, t g and t h It can be determined from the calculation formula of the heating secondary network system, and the only unknowns are τ1 and τ2. Then, by solving the simultaneous equations, the values ​​of the primary network water supply and return water temperatures τ1 and τ2 of the heating system using mass regulation can be determined.

[0071]

[0072] in:

[0073] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0074] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A thermal power unit steam turbine exhaust waste heat heating system, characterized in that: The waste heat heating system includes a steam turbine, a condenser, a cooling tower, a first station heater, an absorption heat pump, a secondary heat exchange station and a coupling controller; The primary network water at the outlet of the absorption heat pump and the primary network water at the outlet of the first station heater do not enter the secondary heat exchange station for heat exchange separately, but are connected through a coupling controller, and the absorption heat pump and the original heating extraction steam are reasonably allocated to the heat network water volume and the extraction steam volume; The input end of the steam turbine is connected to the output end of the boiler, and the steam turbine and the first-station heater are heated by heating steam extraction. The first-station heater is connected to a deaerator, and the secondary heat exchange station is connected to the heating channel of the heating user.

2. A thermal power unit steam turbine exhaust waste heat heating system according to claim 1, characterized in that: The absorption heat pump adopts the first type of lithium bromide absorption heat pump, uses a high-temperature heat source as a driving heat source, a lithium bromide solution as an absorbent, and water as a refrigerant, and recycles a low-temperature heat source.

3. A thermal power unit steam turbine exhaust waste heat heating system according to claim 1, characterized in that: The heat pump is composed of main components such as an evaporator, an absorber, a regenerator, a condenser and a heat exchanger, as well as auxiliary parts such as an air extraction device and a shielded pump.

4. The thermal power unit steam turbine exhaust waste heat heating system according to claim 1, characterized in that: The cooling tower includes an arc pipe, a water storage tank, a water tank, a heating pipe, a water supply pipe, a first water pump and a second water pump. The water storage tank and the water tank are connected through the arc pipe, the first water pump, the second water pump and the water tank are connected through the water supply pipe, and the input end of the condenser is connected to the output end of the water storage tank.

5. The thermal power unit steam turbine exhaust waste heat heating system according to claim 1, characterized in that: When the newly added heating user load is less than the heat pump capacity, the coupling controller adjusts the steam extraction volume and the heat network water flow rate to maintain the two heat network water parameters unchanged, and the excess heat of the heat pump is transported to the original heat network, thereby reducing the heating steam extraction volume.

6. The thermal power unit steam turbine exhaust waste heat heating system according to claim 1, characterized in that: When the newly added heating user load is greater than the heat pump capacity, the absorption heat pump will raise the rated temperature of the heat network return water, and the first station heater will increase the heating extraction steam to provide the remaining required heat. The heat pump outlet water is mixed with the first station heater outlet water to reach the water supply temperature required by the primary network.

7. A method for regulating a steam turbine exhaust waste heat heating system of a thermal power unit according to claim 1, characterized in that: The following steps are involved: S1: Change the supply and return water temperature of the heating network pipeline, while keeping the user's circulating water volume unchanged to maintain the stability of the hydraulic conditions of the heating user system; S2: When all the design parameters are known, the relationship between the supply and return water temperatures of the heating network and the outdoor air temperature can be obtained through the formula. At the corresponding outdoor temperature, the changes in the secondary network supply and return water temperatures in the heating system can be calculated; S3: When the outdoor temperature rises, that is, the heat load decreases, the supply and return water temperatures of the heating network decrease, the required steam extraction volume of the heating unit decreases, and the power generation increases. On the contrary, when the outdoor temperature decreases, the steam extraction volume increases, and the power generation decreases accordingly. S4: The supply and return water temperatures of the heating network are relative to the heat load ratio. As the outdoor temperature increases, the supply and return water temperatures of the primary and secondary networks decrease accordingly, and the supply and return water temperature difference also decreases. The outdoor temperature is high, and the corresponding supply and return water temperatures decrease. At this time, the heat load decreases. If the heat pump and cogeneration are used for heating separately, the heat pump can only operate at full load in the middle of the heating period, and a large capacity will be idle in the early and late stages.

8. A method for regulating a steam turbine exhaust waste heat heating system of a thermal power unit according to claim 7, characterized in that: The regulation method adopts a quality regulation method to analyze the indirect heating mode.

9. A method for regulating a steam turbine exhaust waste heat heating system of a thermal power unit according to claim 7, characterized in that: The inlet and outlet water temperature limits of the absorption heat pump set the primary network supply and return water temperatures to 85 / 50°C.

10. A method for regulating a steam turbine exhaust waste heat heating system of a thermal power unit according to claim 7, characterized in that: The supply and return water temperatures in the low-temperature hot water floor radiant heating system should be determined after calculation, and the supply water temperature should not be greater than 60°C. The supply water temperature in civil buildings should be 35-50°C, and the difference between the supply and return water temperatures should not exceed 10°C. The secondary network supply and return water temperatures are 48 / 40°C.

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