Peak shaving steam supply system for deep waste heat utilization of thermoelectric unit

Abstract

The utility model provides a peak-shaving steam supply system for deep waste heat utilization of a thermoelectric unit, which deeply recovers cold end waste heat and flue gas waste heat of a cogeneration unit, is coupled with a two-stage compression heat pump, extracts waste heat to heat demineralized water, and serves as a primary heat source for supplying industrial steam, so that the waste heat participates in external heat supply; the superheater utilizes the generating capacity of the unit to enable industrial steam to reach steam supply parameters, the waste heat of the unit and the generating capacity are combined for external steam supply, the circulating heat efficiency is improved, the steam supply capacity is improved, meanwhile, the on-grid electricity is reduced, thermoelectric decoupling is achieved, the unit adjusting operation interval is expanded, the operation cost and pollutant emission are reduced, and peak regulation or spot transaction earnings are improved. And a clean, low-carbon, flexible, efficient, economical and energy-saving combined heat and power generation system is constructed.

Description

TECHNICAL FIELD

[0001] The patent belongs to the technical field of flexibility reconstruction of a thermal power unit, and particularly relates to a peak shaving steam supply system for deep waste heat utilization of a thermal power unit. BACKGROUND

[0002] With the rapid development of the industrial industry in China, the demand for industrial steam has increased significantly. As the main steam source, the cogeneration unit occupies a large part of the steam supply market due to its stability and flexibility. The thermal power enterprises actively access the steam users to develop the heat supply market and improve the development level of high-efficiency and clean units. In recent years, the installed capacity of new energy power sources on the power system side has developed rapidly, and the proportion has exceeded half. Due to the volatility and intermittency of the power generation capacity of new energy units, the thermal power units are required to respond quickly and adjust. The utilization hours of the thermal power equipment are in a downward trend, and the average annual load rate is low. Due to the influence of the steam extraction performance of the unit, the access to the industrial steam load is limited, which increases the operation cost and restricts the further optimization of the economy, energy saving and environmental protection of the unit. To realize thermal decoupling and improve the operation flexibility of the unit is a necessary condition for the unit to realize energy saving and carbon reduction, and clean and efficient operation. To enable the unit to realize deep peak shaving during the heat supply period and improve the steam supply capacity during the low load period is the primary goal of building a new power system and helping to achieve the double carbon target on schedule. The peak shaving steam supply flexibility reconstruction technology is the main technical route required by the cogeneration unit at the current development stage. CONTENT OF THE UTILITY MODEL

[0003] The patent aims to provide a peak shaving steam supply system for deep waste heat utilization of a thermal power unit. The cold end waste heat and flue gas waste heat of the cogeneration unit are deeply recovered, coupled with a two-stage compression heat pump, and the waste heat is extracted to heat the desalted water, which is used as the primary heat source for supplying industrial steam. The waste heat participates in external heat supply. The superheater uses the power generation capacity of the unit to make the industrial steam reach the steam supply parameters. The unit waste heat and power generation capacity are combined to supply steam externally, improve the cyclic thermal efficiency, reduce the on-grid power generation capacity while improving the steam supply capacity, realize thermal decoupling, expand the unit adjustment and operation range, reduce the operation cost and pollutant emission, improve the peak shaving or spot transaction income, and build a clean and low-carbon, flexible and efficient, and economical and energy-saving cogeneration system.

[0004] To achieve the above-mentioned purpose, the utility model adopts the following technical solutions:

[0005] The system comprises a two-stage compression heat pump unit, a flue gas waste heat recovery unit, a cold end waste heat recovery unit, a desalted water pipeline, an industrial steam pipeline, an electric superheater, a spray water circulation pipeline, a circulating water pipeline, a desulfurization slurry pipeline, and a flue.

[0006] The two-stage compression heat pump unit comprises a condensing heater, a first throttling valve, an intermediate heat exchanger, a heat supplement heat exchanger, a high-pressure compressor, a second throttling valve, an evaporation heat exchanger, and a low-pressure compressor.

[0007] The desalted water pipeline is connected to the condensing heater water side inlet, the condensing heater water side outlet is connected to the electric superheater inlet, the electric superheater outlet is connected to the industrial steam pipeline for external steam supply;

[0008] The condensing heater heat pump internal circulating working medium side outlet is divided into two routes, one route is connected to the first thrott valve inlet, the second route is connected to the intermediate heat exchanger second side inlet, the first thrott valve outlet is connected to the intermediate heat exchanger first side inlet, the intermediate heat exchanger first side outlet is connected to the heat supplement heat exchanger working medium side inlet, the intermediate heat exchanger second side outlet is connected to the second thrott valve and the working medium side inlet of the evaporating heat exchanger in turn, the evaporating heat exchanger working medium side outlet is connected to the low pressure compressor inlet, the low pressure compressor outlet is connected to the heat supplement heat exchanger working medium side outlet pipeline and then to the high pressure compressor inlet, and the high pressure compressor outlet is connected to the condensing heater working medium side inlet;

[0009] The cold end waste heat recovery unit comprises a circulating water pipeline, a circulating water pump, a first electric isolation valve, a second electric isolation valve, a third electric isolation valve, a fourth electric isolation valve, a first electric regulating valve and a second electric regulating valve;

[0010] The circulating water pipeline is divided into two routes from the condenser outlet pipeline, one route is connected to the evaporating heat exchanger water side inlet, and the first electric isolation valve is arranged on the pipeline, the other route is sent to the cooling tower, and the fourth electric isolation valve and the second electric regulating valve are arranged on the pipeline, the circulating water pipeline from the cooling tower is combined with the evaporating heat exchanger water side outlet circulating water pipeline and then connected to the circulating water pump inlet, the third electric isolation valve is arranged on the pipeline from the cooling tower, the first electric regulating valve and the second electric isolation valve are arranged on the evaporating heat exchanger water side outlet pipeline, and the circulating water pipeline of the circulating water pump outlet is connected to the condenser inlet;

[0011] The flue gas waste heat recovery unit comprises a spray water circulating pump, a slurry circulating pump, a desulfurization tower, a flue gas spray tower, a chimney, a spray water circulating pipeline, a desulfurization slurry pipeline and a flue;

[0012] The spray water circulating pipeline is connected to the spray water circulating pump inlet and outlet, the heat supplement heat exchanger inlet and outlet and the flue gas spray tower water side inlet in turn from the flue gas spray tower water side outlet; the desulfurization slurry pipeline is connected to the slurry circulating pump inlet and outlet and the desulfurization tower slurry side inlet in turn from the desulfurization tower slurry side outlet; and the flue is connected to the desulfurization tower flue gas side inlet and outlet, the flue gas spray tower flue gas side inlet and outlet and the chimney flue gas side inlet and outlet in turn.

[0013] Further, the condensing heater heat pump working medium side inlet and outlet is provided with an intermediate heat supplement loop and an evaporation loop; the intermediate heat supplement loop is sequentially connected with the first throttling valve inlet and outlet, the intermediate heat exchanger first side inlet and outlet and the heat supplement heat exchanger working medium side inlet; the evaporation loop is sequentially connected with the intermediate heat exchanger second side inlet and outlet, the second throttling valve inlet and outlet, the evaporation heat exchanger working medium side inlet and outlet and the low-pressure compressor inlet; the heat supplement loop from the heat supplement heat exchanger outlet and the evaporation loop from the low-pressure compressor outlet are combined and sequentially connected with the high-pressure compressor inlet and outlet and the condensing heater working medium side inlet.

[0014] Further, the flue includes a desulfurization tower outlet flue, which is located at the flue gas outlet side of the desulfurization tower, and is sequentially connected with the flue gas side inlet and outlet of the flue gas spray tower and the chimney inlet, so that the flue gas from the desulfurization tower is further sprayed and cooled by the flue gas spray tower; the water side outlet of the flue gas spray tower is sequentially connected with the inlet and outlet of the spray water circulating pump, the inlet and outlet of the heat supplement heat exchanger and the water side inlet of the flue gas spray tower, so that the spray water heated after spraying the flue gas is sent into the heat supplement heat exchanger as a medium-temperature heat source to provide medium-temperature waste heat for the heat pump, the flue gas waste heat is recovered to supply heat to the outside, and the efficiency of the boiler is improved.

[0015] Compared with the conventional technology, the utility model has the advantages of:

[0016] (1) the low-temperature heat source of the steam turbine cold end waste heat is used as the low-temperature heat source of the double-stage compression heat pump, so that the low-temperature heat source participates in external heat supply, the circulating heat efficiency is improved, the coal consumption of power generation is reduced, and the operation economy is improved;

[0017] (2) the spray tower is additionally provided, the flue gas waste heat at the tail of the desulfurization tower is recovered, the flue gas waste heat is used as the medium-temperature heat source of the double-stage compression heat pump, deep waste heat utilization is realized, the energy utilization rate is improved, and the coal consumption of power generation and heat supply is further reduced;

[0018] (3) the water quality in the spray tower is good, and the water can directly enter the heat exchanger for heat exchange, so that the problems of heat exchanger blockage and corrosion caused by the recovery of the waste heat of the desulfurization slurry are solved, the outlet of the desulfurization tower is saturated flue gas, and a part of condensate water can also be recovered, so that the water consumption of the desulfurization tower is reduced, and the waste heat utilization method is efficient and energy-saving;

[0019] (4) the heat pump is divided into double-stage compression, the cold end waste heat and the flue gas waste heat are recovered in stages, the compressor power consumption is reduced, the heat pump working temperature difference is reduced, and the heat pump heating performance coefficient is greatly improved;

[0020] (5) the heat pump is used as the primary heat source of industrial steam heating, the recovered waste heat is used to meet the preliminary heating demand of the desalted water, the high-grade electric energy drives the electric superheater to make the steam supply meet the parameter requirements, the energy is reasonably utilized in stages, the energy utilization efficiency is improved, the heat supply capacity is increased while the peak shaving depth is increased, the heat and electricity are decoupled, and the operation regulation flexibility, economy and environmental protection of the unit are improved. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 Figure 1 is a structural schematic diagram of a peak shaving steam supply system of a thermoelectric unit deep waste heat utilization

[0022] Wherein, 1 - condensing heater; 2 - first throttling valve; 3 - intermediate heat exchanger; 4 - heat supplement heat exchanger; 5 - high-pressure compressor; 6 - second throttling valve; 7 - evaporator; 8 - low-pressure compressor; 9 - spray water circulating pump; 10 - desulfurization slurry circulating pump; 11 - desulfurization tower; 12 - flue gas spray tower; 13 - chimney; 14 - circulating water pump; 15 - first electric isolation valve; 16 - first electric regulating valve; 17 - second electric isolation valve; 18 - third electric isolation valve; 19 - second electric regulating valve; 20 - fourth electric isolation valve; 21 - electric superheater. DETAILED DESCRIPTION:

[0023] Referring to Figure 1 , the system comprises a two-stage compression heat pump unit, a flue gas waste heat recovery unit, a cold-end waste heat recovery unit, a demineralized water pipeline, an industrial steam pipeline, an electric superheater 21, a spray water circulating pipeline, a circulating water pipeline, a desulfurization slurry pipeline, and a flue;

[0024] The two-stage compression heat pump unit comprises a condensing heater 1, a first throttling valve 2, an intermediate heat exchanger 3, a heat supplement heat exchanger 4, a high-pressure compressor 5, a second throttling valve 6, an evaporator 7, and a low-pressure compressor 8;

[0025] The cold-end waste heat recovery unit comprises a circulating water pipeline, a circulating water pump 14, a first electric isolation valve 15, a second electric isolation valve 17, a third electric isolation valve 18, a fourth electric isolation valve 20, a first electric regulating valve 16, and a second electric regulating valve 19;

[0026] The flue gas waste heat recovery unit comprises a spray water circulating pump 9, a slurry circulating pump 10, a desulfurization tower 11, a flue gas spray tower 12, a chimney 13, a spray water circulating pipeline, a desulfurization slurry pipeline, and a flue;

[0027] The demineralized water pipeline is connected to the water side inlet of the condensing heater 1, and the primary heating of the demineralized water is performed by using the heat pump heating capacity. The water side outlet of the condensing heater 1 is connected to the inlet of the electric superheater 21, and the outlet of the electric superheater 21 is connected to the industrial steam pipeline to supply steam to the steam user. The electric superheater 21 uses the power generation capacity of the unit to superheat the steam to the steam supply parameters, thereby realizing peak shaving steam supply.

[0028] The condenser heater 1 heat pump internal circulation working medium side outlet is divided into two routes, referred to as "one route, two routes" here, one route is connected to the first throttle valve 2 inlet, two routes are connected to the intermediate heat exchanger 3 second side inlet, the first throttle valve 2 outlet is connected to the intermediate heat exchanger 3 first side inlet, the intermediate heat exchanger 3 first side outlet is connected to the heat supplement heat exchanger 4 working medium side inlet, the intermediate heat exchanger 3 second side outlet is connected to the second throttle valve 6 and the evaporative heat exchanger 7 working medium side inlet in turn, the evaporative heat exchanger 7 working medium side outlet is connected to the low-pressure compressor 8 inlet, the low-pressure compressor 8 outlet is connected to the heat supplement heat exchanger 4 working medium side outlet pipeline, and then connected to the high-pressure compressor 5 inlet, and the high-pressure compressor 5 outlet is connected to the condenser heater 1 working medium side inlet; further, the condenser heater 1 heat pump working medium side inlet and outlet are provided with an intermediate heat supplement loop and an evaporation loop; the intermediate heat supplement loop is connected to the first throttle valve 2 inlet and outlet, the intermediate heat exchanger 3 first side inlet and outlet, and the heat supplement heat exchanger 4 working medium side inlet in turn; the evaporation loop is connected to the intermediate heat exchanger 3 second side inlet and outlet, the second throttle valve 6 inlet and outlet, the evaporative heat exchanger 7 working medium side inlet and outlet, and the low-pressure compressor 8 inlet in turn; the heat supplement loop from the heat supplement heat exchanger 4 outlet and the evaporation loop from the low-pressure compressor 8 outlet are combined and then connected to the high-pressure compressor 5 inlet and outlet and the condenser heater 1 working medium side inlet in turn.

[0029] The circulating water pipeline is divided into two routes from the condenser outlet pipeline, one route is connected to the evaporative heat exchanger 7 water side inlet, and a first electric isolation valve 15 is arranged on the pipeline, and the other route is sent to the cooling tower, and a fourth electric isolation valve 20 and a second electric regulating valve 19 are arranged on the pipeline; the circulating water pipeline from the cooling tower is combined with the evaporative heat exchanger 7 water side outlet circulating water pipeline and then connected to the circulating water pump 14 inlet; a third electric isolation valve 18 is arranged on the pipeline from the cooling tower; a first electric regulating valve 16 and a second electric isolation valve 17 are arranged on the evaporative heat exchanger 7 water side outlet pipeline; the circulating water pipeline from the circulating water pump 14 outlet is connected to the condenser inlet; further, the circulating water pipeline from the condenser is divided into two routes, one route is connected to the evaporative heat exchanger 7 inlet and outlet and then combined with the circulating water pipeline from the cooling tower, and the circulating water pump 14 is arranged on the combined circulating water main pipeline; the third electric isolation valve 18 is arranged on the pipeline from the cooling tower, the fourth electric isolation valve 20 is arranged on the circulating water pipeline branch to the cooling tower, which is used for controlling the operation and removal of the cooling tower, the second electric regulating valve 19 is arranged on the circulating water pipeline branch to the cooling tower, which is used for controlling the circulating water flow into the cooling tower; the first electric isolation valve 15 is arranged on the pipeline to the evaporative heat exchanger 7 circulating water inlet, the first electric regulating valve 16 and the second electric isolation valve 17 are arranged on the evaporative heat exchanger 7 outlet circulating water pipeline, which are used for controlling the operation and removal of the low-temperature heat source of the heat pump, and the electric regulating valve 16 is arranged on the evaporative heat exchanger 7 outlet circulating water pipeline, which is used for controlling the circulating water flow into the evaporative heat exchanger 7 to control the low-temperature waste heat recovery amount of the heat pump.

[0030] The spray water circulation pipeline is connected in sequence from the water side outlet of the flue gas spray tower 12 to the inlet and outlet of the spray water circulating pump 9, the inlet and outlet of the heat supplementing heat exchanger 4, and the water side inlet of the flue gas spray tower 12; the desulfurization slurry pipeline is connected in sequence from the slurry side outlet of the desulfurization tower 11 to the inlet and outlet of the slurry circulating pump 10 and the slurry side inlet of the desulfurization tower 11; and the flue is connected in sequence to the flue gas side inlet and outlet of the desulfurization tower 11, the flue gas side inlet and outlet of the flue gas spray tower 12, and the flue gas side inlet and outlet of the chimney 13.

[0031] The flue includes a desulfurization tower outlet flue, which is located at the flue gas outlet side of the desulfurization tower 11 and is connected in sequence to the flue gas side inlet and outlet of the flue gas spray tower 12 and the inlet of the chimney 13, so that the flue gas at the outlet of the desulfurization tower 11 is further sprayed and cooled by the flue gas spray tower 12; the water side outlet of the flue gas spray tower 12 is connected in sequence to the inlet and outlet of the spray water circulating pump 9, the inlet and outlet of the heat supplementing heat exchanger 4, and the water side inlet of the flue gas spray tower 12, so that the sprayed and heated spray water is sent to the heat supplementing heat exchanger 4 as a medium temperature heat source to provide medium temperature waste heat for the heat pump, to recover flue gas waste heat for external heating, and to improve the efficiency of the boiler.

[0032] The desulfurization tower 11 is additionally provided with a spray tower 12, the flue gas at the outlet of the desulfurization tower 11 is further sprayed and cooled, and the water and heat in the saturated flue gas are recovered; the sprayed flue gas is discharged to the atmosphere through the chimney 13, the flue gas is “white”-eliminated, the sprayed and heated spray water enters the heat pump heat supplementing heat exchanger 4 as a medium temperature heat source, the heat pump heating performance is improved, the circulating water from the outlet of the condenser is divided into two paths, one path enters the evaporator 7 of the heat pump as a low temperature heat source to extract waste heat, and the other path is sent to the cooling tower for cooling, the mixed water from the outlet of the evaporator 7 and the cooling tower is sent back to the condenser, the recovered cold end waste heat is adjusted according to the industrial steam load, the first electric regulating valve 16 is used to control the flow distribution of the circulating water between the cooling tower and the evaporator 7, the compression type heat pump is divided into two stages to reduce the power consumption of the compressor under the premise of ensuring the heating capacity, the COP of the heat pump is improved, the cold end waste heat of the power generation cycle and the flue gas waste heat are recovered in sequence according to the principle of “temperature matching and gradient utilization”, the cycle thermal efficiency is improved, the demineralized water is first heated by the heat pump condensing heater 1, then enters the electric superheater 21, and is superheated to the required parameters of the steam supply by the power generation capacity of the unit, and is supplied externally, the system recovers waste heat and reduces the online power of the unit, realizes the supply of heat and the supply of steam for peak shaving, and improves the economic efficiency, energy saving and environmental protection of the unit operation.

[0033] The system has two operation modes: steam supply and non-steam supply.

[0034] When supplying steam, the first electric isolation valve 15 and the second electric isolation valve 17 are opened, and the third electric isolation valve 18 and the fourth electric isolation valve 20 are determined to be opened or closed according to the steam supply load demand. When the steam supply demand is large, and the desalted water basic heat source demand can accommodate all the cold end waste heat, the third electric isolation valve 18 and the fourth electric isolation valve 20 are closed, otherwise, they are opened. The first electric regulating valve 16 and the second electric regulating valve 19 are used to adjust the distribution of the circulating water flow entering the evaporator 7 as a low temperature heat source and the circulating water flow sent to the cooling tower. The circulating water pump 14 outlet circulating water is divided into two paths, one path enters the evaporative heat exchanger 7 to be extracted by the heat pump to absorb low temperature waste heat, and the other path is sent to the cooling tower to be sprayed and cooled. The cooling tower return water and the evaporative heat exchanger 7 outlet circulating water are combined and sent to the condenser together. When the steam supply demand is large, all the circulating water enters the evaporative heat exchanger 7 as a low temperature heat source, and is not sent to the cooling tower. The induced draft fan outlet flue gas enters the desulfurization tower 11 to be sprayed by the desulfurization slurry to remove sulfur in the flue gas, and at the same time, the flue gas is cooled. The slurry circulating pump 10 is used to send the desulfurization slurry at the bottom of the desulfurization tower 11 to the top of the desulfurization tower 11 to be sprayed downward. The desulfurization tower 11 outlet flue gas is saturated flue gas. The saturated flue gas enters the flue gas spray tower 12 to be sprayed and cooled again. The sprayed water is heated and falls into the tower bottom, and at the same time, part of the water vapor in the flue gas condenses and also falls into the tower bottom. The flue gas cooled twice is discharged to the atmosphere through the chimney 13. Since the temperature of the flue gas at this time is close to the atmosphere, it will not quickly condense to produce water vapor droplets, achieving the purpose of "white smoke elimination" of the flue gas. The spray water circulating pump 9 sends the tower bottom spray water to the heat supplement heat exchanger 4 as a heat pump medium temperature heat source. In the condensing heater 1, the heat pump working medium condensed and released heat heats the desalted water on the other side of the heat exchanger, and the generated condensed working medium is divided into two paths. One path enters the intermediate heat exchanger 3 to absorb the heat of the working medium of the other path after being reduced in pressure by the first throttling valve 2, and then enters the heat supplement heat exchanger 4 to absorb the flue gas waste heat carried by the sprayed water. The generated heat pump working medium steam is mixed with the working medium steam at the outlet of the two-way low pressure compressor 8, and then enters the high pressure compressor 5 to be compressed, and then enters the condensing heater 1 to be condensed and released heat. The two-way working medium is heated by the intermediate heat exchanger 3 after heating the working medium of one path, and then enters the evaporator 7 to evaporate and absorb the cold end waste heat carried by the circulating water on the other side of the heat exchanger after being reduced in pressure by the second throttling valve 6. The evaporated working medium is compressed by the low pressure compressor 8 and mixed with the working medium of one path, and then enters the high pressure compressor 5 to be two-stage compressed.

[0035] When not supplying steam, the first electric isolation valve 15 and the second electric isolation valve 17 are closed, and the third electric isolation valve 18 and the fourth electric isolation valve 20 are opened. At this time, the circulating water from the cooling tower is all sent to the condenser after being pressurized by the circulating water pump 14, and then is sprayed and cooled in the cooling tower after absorbing the cold end waste heat in the condenser.

Claims

1. A peak-shaving steam supply system for deep waste heat utilization of a thermal power unit, characterized in that, Mainly includes: Two-stage compression heat pump unit, flue gas waste heat recovery unit, cold end waste heat recovery unit, demineralized water pipeline, industrial steam pipeline, electric superheater (21), spray water circulation pipeline, circulating water pipeline, desulfurization slurry pipeline, flue; The two-stage compression heat pump system includes a condenser heater (1), a first throttle valve (2), an intermediate heat exchanger (3), a supplementary heat exchanger (4), a high-pressure compressor (5), a second throttle valve (6), an evaporator heat exchanger (7), and a low-pressure compressor (8). The demineralized water pipeline is connected to the water-side inlet of the condenser heater (1), the water-side outlet of the condenser heater (1) is connected to the inlet of the electric superheater (21), and the outlet of the electric superheater (21) is connected to the industrial steam pipeline for external steam supply. The heat pump internal circulation working fluid outlet of the condenser heater (1) is divided into two paths, referred to here as "path one and path two". Path one is connected to the inlet of the first throttle valve (2), and path two is connected to the second side inlet of the intermediate heat exchanger (3). The outlet of the first throttle valve (2) is connected to the first side inlet of the intermediate heat exchanger (3). The first side outlet of the intermediate heat exchanger (3) is connected to the working fluid side inlet of the supplementary heat exchanger (4). The second side outlet of the intermediate heat exchanger (3) is connected in sequence to the working fluid side inlet of the second throttle valve (6) and the evaporator heat exchanger (7). The working fluid side outlet of the evaporator heat exchanger (7) is connected to the inlet of the low-pressure compressor (8). The outlet of the low-pressure compressor (8) and the working fluid side outlet of the supplementary heat exchanger (4) are connected together and then connected to the inlet of the high-pressure compressor (5). The outlet of the high-pressure compressor (5) is connected to the working fluid side inlet of the condenser heater (1). The cold end waste heat recovery unit includes a circulating water pipeline, a circulating water pump (14), a first electric isolation valve (15), a second electric isolation valve (17), a third electric isolation valve (18), a fourth electric isolation valve (20), a first electric regulating valve (16), and a second electric regulating valve (19). The circulating water pipeline is divided into two paths from the condenser outlet pipeline. One path is connected to the water-side inlet of the evaporator heat exchanger (7), and a first electric isolation valve (15) is installed on the pipeline. The other path is sent to the cooling tower, and a fourth electric isolation valve (20) and a second electric regulating valve (19) are installed on the pipeline. The circulating water pipeline from the cooling tower is combined with the circulating water pipeline at the water-side outlet of the evaporator heat exchanger (7) and then connected to the inlet of the circulating water pump (14). A third electric isolation valve (18) is installed on the pipeline from the cooling tower. A first electric regulating valve (16) and a second electric isolation valve (17) are installed on the water-side outlet pipeline of the evaporator heat exchanger (7). The circulating water pipeline at the outlet of the circulating water pump (14) is connected to the condenser inlet. The flue gas waste heat recovery unit includes a spray water circulation pump (9), a slurry circulation pump (10), a desulfurization tower (11), a flue gas spray tower (12), a chimney (13), a spray water circulation pipe, a desulfurization slurry pipe, and a flue. The spray water circulation pipeline is connected in sequence from the water side outlet of the flue gas spray tower (12) to the inlet and outlet of the spray water circulation pump (9), the inlet and outlet of the heat exchanger (4), and the water side inlet of the flue gas spray tower (12); the desulfurization slurry pipeline is connected in sequence from the slurry side outlet of the desulfurization tower (11) to the inlet and outlet of the slurry circulation pump (10) and the slurry side inlet of the desulfurization tower (11); the flue is connected in sequence to the flue gas side inlet and outlet of the desulfurization tower (11), the flue gas side inlet and outlet of the flue gas spray tower (12), and the flue gas side inlet and outlet of the chimney (13).

2. The peak-shaving steam supply system for deep waste heat utilization of a thermal power unit according to claim 1, characterized in that, The condenser heater (1) has an intermediate heating loop and an evaporation loop set at the inlet and outlet of the heat pump working fluid side. The intermediate heating loop is connected in sequence to the inlet and outlet of the first throttle valve (2), the inlet and outlet of the first side of the intermediate heat exchanger (3), and the working fluid side inlet of the heating exchanger (4). The evaporation loop is connected in sequence to the inlet and outlet of the secondary side of the intermediate heat exchanger (3), the inlet and outlet of the second throttle valve (6), the inlet and outlet of the working fluid side of the evaporation heat exchanger (7), and the inlet of the low-pressure compressor (8). The heating loop from the outlet of the heating exchanger (4) and the evaporation loop from the outlet of the low-pressure compressor (8) are merged and then connected in sequence to the inlet and outlet of the high-pressure compressor (5) and the working fluid side inlet of the condenser heater (1).

3. A peak-shaving steam supply system for deep waste heat utilization of a thermal power unit according to claim 1, characterized in that, The flue includes the desulfurization tower outlet flue, which is located on the flue gas outlet side of the desulfurization tower (11). The desulfurization tower outlet flue is connected in sequence to the flue gas side inlet and outlet of the flue gas spray tower (12) and the inlet of the chimney (13). The flue gas spray tower (12) further sprays and cools the flue gas at the outlet of the desulfurization tower (11). The water side outlet of the flue gas spray tower (12) is connected in sequence to the inlet and outlet of the spray water circulation pump (9), the inlet and outlet of the heat exchanger (4), and the water side inlet of the flue gas spray tower (12). The spray water that has been heated after spraying the flue gas is sent into the heat exchanger (4) as a medium-temperature heat source to provide medium-temperature waste heat for the heat pump. The waste heat of the flue gas is recovered and supplied to the outside for heating, thereby improving the boiler efficiency.

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