Energy storage cascade heating and heat supply energy system suitable for novel electric power system

Abstract

The invention relates to the technical field of energy utilization, in particular to an energy storage cascade heating and heat supply energy system suitable for a novel electric power system, which comprises a unit module, a first-stage heating module, a second-stage heating module and a water supply module, a main steam exhaust pipe is communicated with the unit module, and a first-stage steam supply branch and a second-stage steam supply branch are both communicated with the main steam exhaust pipe; the first-stage steam supply branch and the second-stage steam supply branch supply steam to the absorption heat pump and the peak heater respectively, and the second-stage recovery pipe is used for converging steam discharged after heating of the first-stage heating module and steam discharged after heating of the second-stage heating module and then conveying the steam back to the absorption heat pump again. The medium-pressure cylinder exhaust steam is used as a driving steam source, the steam cooling drain water of the second-stage heating module is used as a low-temperature heat source, and the cooling drain water of the second-stage heating module is recycled, so that compared with the mode that the medium-pressure cylinder exhaust steam used in a domestic factory only passes through a first-stage heater at present, the heat utilization rate is greatly increased; and the heat of the condensation water in an interval from about 70 DEG C to about 20 DEG C is fully utilized.

Description

Technical Field

[0001] The invention relates to the technical field of energy utilization, and in particular to an energy storage cascade heating and heat supply energy system adapted to a new type of power system. Background Art

[0002] High back pressure heating means increasing the pressure of the exhaust steam in the condenser and using circulating water from the heat network to cool the exhaust steam, thereby using the latent heat of vaporization of the exhaust steam from the steam turbine unit to heat the circulating water and achieve heating. This technology has low heating energy consumption, but has the following disadvantages: (1) Strong coupling between heat and electricity and poor operational flexibility. When the heat supply is constant, the electrical load regulation capacity is less than 5%; (2) High requirements for the operational stability of the heat network. When the circulating water from the heat network leaks, it may lead to insufficient cooling water for the unit and an increase in the exhaust steam temperature, thereby threatening the safe operation of the unit.

[0003] Both the medium- and low-pressure interconnecting pipe heating and the low-pressure cylinder zero-output heating technology use the medium-pressure cylinder exhaust steam to heat the circulating water of the heat network. Under this method, the unit operation flexibility is greater, but the energy quality of the medium-pressure cylinder exhaust steam is relatively high. If it is directly used to heat the circulating water of the heat network, there will be a loss of work capacity and high heating energy consumption. Summary of the invention

[0004] The purpose of this section is to summarize some aspects of embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the specification abstract and the invention title of this application to avoid blurring the purpose of this section, the specification abstract and the invention title, and such simplifications or omissions cannot be used to limit the scope of the present invention.

[0005] In view of the fact that the above-mentioned unit is not flexible enough and has high energy consumption when directly using the exhaust steam from the intermediate pressure cylinder for heating, the present invention is proposed.

[0006] Therefore, the object of the present invention is to provide an energy storage cascade heating energy system that is adaptable to the new power system.

[0007] To solve the above technical problems, the present invention provides the following technical solutions: a storage cascade heating energy system adapted to the new power system, comprising a unit module, and also a first-level heating module, including a main exhaust pipe, a first-level steam supply branch, an absorption heat pump, and a first-level exhaust pipe; a second-level heating module, including a second-level steam supply branch, a peak heater, a second-level exhaust pipe, and a second-level recovery pipe; a water supply module, including a heat storage tank; the main exhaust pipe is connected to the unit module, the first-level steam supply branch and the second-level steam supply branch are both connected to the main exhaust pipe, the first-level steam supply branch and the second-level steam supply branch supply steam to the absorption heat pump and the peak heater respectively, and the second-level recovery pipe is used to merge the heated exhaust steam of the first-level heating module with the exhaust steam of the second-level heating module and then re-transmit it back to the absorption heat pump.

[0008] As a preferred solution of the energy storage cascade heating and heat supply energy system adapted to the new power system described in the present invention, the unit module includes a medium-pressure cylinder, a low-pressure cylinder, a generator, a condenser and a condensate pump. The medium-pressure cylinder, the low-pressure cylinder and the generator are coaxially arranged, the exhaust steam of the low-pressure cylinder is connected to the condenser, and the drain water of the condenser is connected to the condensate pump.

[0009] As a preferred solution of the energy storage cascade heating energy system adapted to the new power system described in the present invention, a connecting steam pipe and a connecting branch pipe are provided between the medium-pressure cylinder and the low-pressure cylinder, and regulating valves are provided on the connecting steam pipe and the connecting branch pipe.

[0010] As a preferred solution of the energy storage cascade heating energy system adapted to the new power system described in the present invention, a main exhaust pipe is added to the front end of the regulating valve of the connecting steam pipe, the input end of the main exhaust steam pipe is connected with the exhaust steam of the medium pressure cylinder through the connecting steam pipe, and the output end of the main exhaust steam pipe is respectively connected with the input ends of the first-level steam supply branch and the second-level steam supply branch.

[0011] As a preferred solution of the energy storage cascade heating energy system adapted to the new power system described in the present invention, the absorption heat pump is provided with a cold side and a hot side, and the hot side of the absorption heat pump is provided with two sections of heaters, namely the first heater and the second heater, and the output end of the first-level steam supply branch is connected to the input end of the first heater.

[0012] As a preferred solution of the energy storage cascade heating energy system adapted to the new power system described in the present invention, the output end of the secondary steam supply branch is connected to the steam inlet end of the peak heater, and the exhaust end of the peak heater is provided with a secondary exhaust pipe, and the secondary exhaust pipe is connected to the secondary recovery pipe.

[0013] As a preferred solution of the energy storage cascade heating energy system adapted to the new power system described in the present invention, the secondary recovery pipe is connected to the input end of the second heater of the absorption heat pump, and the output end of the first heater is connected to the secondary recovery pipe.

[0014] As a preferred solution of the energy storage cascade heating energy system adapted to the new power system described in the present invention, the output end of the second heater is connected to the input end of the drain pipe, the output end of the first heater is connected to the drain pipe, and the output end of the drain pipe is connected to the input end of the condensate pump.

[0015] As a preferred solution of the energy storage cascade heating energy system adapted to the new power system described in the present invention, the main exhaust steam pipe, the first-level steam supply branch, and the second-level steam supply branch are all provided with a check valve, a regulating valve, and an isolation valve in sequence.

[0016] As a preferred solution of the energy storage cascade heating and heat supply energy system adapted to the new power system described in the present invention, the water supply module also includes a heating return pipe, a connecting water pipe and a water supply pipe. The heating return pipe is connected to the cold side of the absorption heat pump, the cold side of the absorption heat pump is connected to the water inlet end of the peak heater, the drainage end of the peak heater is connected to the heat storage tank, and the drainage end of the heat storage tank is connected to the water supply pipe.

[0017] Beneficial effects of the present invention: The present invention adopts the exhaust steam of the medium-pressure cylinder as the driving steam source and the steam cooling drain of the secondary heating module as the low-temperature heat source, and recovers the cooling drain of the secondary heating module, thereby greatly improving the heat utilization rate compared with the current domestic factory mode in which the exhaust steam of the medium-pressure cylinder only passes through the primary heater mode, and fully utilizes the heat of the condensate in the range of about 70°C to about 20°C. In the heating season, the hot water storage tank stores or releases hot water to achieve stable output of the residential heating heat load when the unit's electrical load fluctuates greatly. In the non-heating season, the hot water storage tank can store heat to assist in reducing the external power supply load of the unit, and the heat stored in the non-heating season can be used for the heating needs of residents in the heating season. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of 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 described below 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 work.

[0019] Figure 1 It is an overall schematic diagram of an energy storage cascade heating energy system adapted to the new power system.

[0020] Figure 2 The figure is a flow chart of a storage cascade heating energy system adapted to the new power system. DETAILED DESCRIPTION

[0021] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0022] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0023] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0024] Secondly, the present invention is described in detail with reference to the schematic diagram. When describing the embodiments of the present invention in detail, for the sake of convenience, the cross-sectional diagrams showing the device structure will not be partially enlarged according to the general scale, and the schematic diagrams are only examples, which should not limit the scope of protection of the present invention. In addition, in actual production, the three-dimensional dimensions of length, width and depth should be included.

[0025] Example 1

[0026] Reference Figure 1 - Figure 2 , which is the first embodiment of the present invention, and provides an energy storage cascade heating and heat supply energy system adapted to a new type of power system, comprising a unit module 100, and also comprising a primary heating module 200, comprising a main exhaust pipe 201, a primary steam supply branch 202, an absorption heat pump 203, and a primary exhaust pipe 204; a secondary heating module 300, comprising a secondary steam supply branch 301, a peak heater 302, a secondary exhaust pipe 303, and a secondary recovery pipe 304; a water supply module 400, comprising a hot water storage tank 403; the main exhaust pipe 201 is connected to the unit module 100, the primary steam supply branch 202 and the secondary steam supply branch 301 are both connected to the main exhaust pipe 201, the primary steam supply branch 202 and the secondary steam supply branch 301 supply steam to the absorption heat pump 203 and the peak heater 302 respectively, and the secondary recovery pipe 304 is used to transfer the primary heating module 2 00 is combined with the exhaust steam of the secondary heating module 300 and then fed back to the absorption heat pump 203. The exhaust steam of the intermediate pressure cylinder 101 is provided to the absorption heat pump 203 and the peak heater 302 through the main exhaust pipe 201, the primary steam supply branch 202 and the secondary steam supply branch 301. The water supply module 400 feeds the external heating return water into the primary heating module 200 and the secondary heating module 300 in sequence. The primary heating module 200 and the secondary heating module 300 use the exhaust steam of the intermediate pressure cylinder 101 to perform step-by-step heating on the heating return water. At the same time, the cooling drain water after heat exchange of the secondary heating module 300 is recovered for the preliminary heating of the primary heating module 200. The heated heating return water is stored in the heat storage tank 403 and can be used for external heating. At the same time, the exhaust steam of the unit can be adjusted by adjusting the steam intake of the primary heating module 200 and the secondary heating module 300.

[0027] Specifically, the unit module 100 includes a medium-pressure cylinder 101, a low-pressure cylinder 102, a generator 103, a condenser 106 and a condensate pump 107. The medium-pressure cylinder 101, the low-pressure cylinder 102 and the generator 103 are coaxially arranged, the exhaust steam of the low-pressure cylinder 102 is connected to the condenser 106, and the drainage of the condenser 106 is connected to the condensate pump 107. The medium-pressure cylinder 101 and the low-pressure cylinder 102 can be heated by medium- and low-pressure connecting pipes or by zero-output mode of the low-pressure cylinder 102. The condenser 106 and the condensate pump 107 are used to condense the exhaust steam into condensate and discharge it.

[0028] Furthermore, a connecting steam pipe 104 and a connecting branch pipe 105 are provided between the medium-pressure cylinder 101 and the low-pressure cylinder 102, and regulating valves are provided on the connecting steam pipe 104 and the connecting branch pipe 105. According to the heat load demand, the medium- and low-pressure connecting pipe heating or the low-pressure cylinder 102 zero-output heating mode is selected; medium- and low-pressure connecting pipe heating mode: the regulating valve on the connecting steam pipe 104 is partially opened, and the regulating valve on the connecting branch pipe 105 is fully opened; low-pressure cylinder 102 zero-output heating mode: the regulating valve on the connecting steam pipe 104 is closed, and the regulating valve on the connecting branch pipe 105 is fully opened. By controlling the regulating valves on the connecting steam pipe 104 and the connecting branch pipe 105, the operation mode of the medium-pressure cylinder 101 and the low-pressure cylinder 102 is changed.

[0029] Furthermore, a main exhaust pipe 201 is added to the front end of the regulating valve through the connecting steam pipe 104. The input end of the main exhaust pipe 201 is connected to the exhaust steam of the intermediate pressure cylinder 101 through the connecting steam pipe 104. The output end of the main exhaust pipe 201 is respectively connected to the input ends of the first-level steam supply branch 202 and the second-level steam supply branch 301. The main exhaust pipe 201 is used to introduce the exhaust steam of the intermediate pressure cylinder 101 into the first-level heating module 200 and the second-level heating module 300. The first-level steam supply branch 202 and the second-level steam supply branch 301 are respectively used to supply steam to the absorption heat pump 203 and the peak heater 302.

[0030] Specifically, in the heating season, the unit operates in the low-pressure cylinder 102 zero-output mode or the medium-low pressure connecting pipe heating mode. During the heating season, partial heating or full heating is selected according to the heating amount, the unit's electrical load and the real-time load of the heat users. In addition, according to the deep adjustment requirements of the power grid, the steam extraction amount of the secondary heating module 300 is controlled to adjust the unit's electrical load, and the water tank is used to store heat and adjust the heating. In the non-heating season, the unit operates in a pure condensing state, and controls whether to extract steam for heat storage based on the transaction electricity price and the unit's power generation cost.

[0031] Example 2

[0032] Reference Figure 1 - Figure 2, which is the second embodiment of the present invention. This embodiment is different from the first embodiment in that: the absorption heat pump 203 is provided with a cold side and a hot side, and the hot side of the absorption heat pump 203 is provided with two-stage heaters, namely a first heater and a second heater, and the output end of the first-stage steam supply branch 202 is connected to the input end of the first heater. The absorption heat pump 203 can simultaneously utilize the exhaust steam of the medium-pressure cylinder 101 and the peak heater 302.

[0033] Specifically, the output end of the secondary steam supply branch 301 is connected to the steam inlet end of the peak heater 302, and the exhaust end of the peak heater 302 is provided with a secondary exhaust pipe 303, which is connected to the secondary recovery pipe 304. The steam extraction amount of the intermediate pressure cylinder exhaust depends on the unit type and the unit electrical load. The steam extraction distribution considers ensuring that the heating return water temperature in the primary heating module 200 is increased to 70°C, and the temperature in the secondary heating module 300 is increased to 100°C. .

[0034] Furthermore, the secondary recovery pipe 304 is communicated with the input end of the second heater of the absorption heat pump 203 , and the output end of the first heater is communicated with the secondary recovery pipe 304 .

[0035] Furthermore, the output end of the second heater is connected to the input end of the drain pipe 205 , the output end of the first heater is connected to the drain pipe 205 , and the output end of the drain pipe 205 is connected to the input end of the condensate pump 107 .

[0036] Furthermore, the main exhaust pipe 201, the first-level steam supply branch 202, and the second-level steam supply branch 301 are all provided with a check valve, a regulating valve, and an isolation valve in sequence.

[0037] Under the scheme of the present invention, when the electric load is determined, the external heating load of the unit can fluctuate between 0 and 300%.

[0038] In non-heating season conditions, the minimum external power supply load of a conventional pure condensing unit is generally 30% THA; under the patent of the present invention, the minimum external power supply load of a pure condensing unit can be reduced to 20% THA.

[0039] It can realize flexible power quotation and flexible operation adjustment of units under power spot trading, and achieve a substantial increase in power spot trading revenue.

[0040] Example 3

[0041] Reference Figure 1 - Figure 2, which is the third embodiment of the present invention. This embodiment is different from the above embodiments in that: the water supply module 400 also includes a heating return pipe 401, a connecting water pipe 402 and a water supply pipe 404, the heating return pipe 401 is connected to the cold side of the absorption heat pump 203, the cold side of the absorption heat pump 203 is connected to the water inlet end of the peak heater 302, the drainage end of the peak heater 302 is connected to the hot water storage tank 403, and the drainage end of the hot water storage tank 403 is connected to the water supply pipe 404.

[0042] Specifically, a regulating valve and an isolation valve are provided on the water supply pipe 404 in sequence.

[0043] Furthermore, during the heating season, the unit operates in a low-pressure cylinder zero-output heating mode or a medium- and low-pressure connecting pipe heating mode to obtain the relationship between the maximum heating capacity of the unit and the unit's electrical load. When the electrical load is determined, the ratio of the real-time load of the heat user to the maximum heating capacity of the unit is determined, and then the heat storage tank 403 is selected to fully open the water supply or partially open the water supply to meet the user's heating needs. In addition, the steam extraction amount of the secondary heating module 300 can be controlled according to the deep adjustment requirements of the power grid to realize the supply adjustment of the unit's thermal load and electrical load.

[0044] In the non-heating season, the unit operates in a pure condensing state. Based on the unit's power generation cost and the market trading electricity price, it is determined whether it is necessary to store energy in the heat storage tank. The exhaust steam of the unit is sent to the primary heating module 200 and the secondary heating module 300 to heat the heating return water, which is then stored in the cross-seasonal heat storage tank 403, thereby adjusting the power generation of the unit.

[0045] Importantly, it should be noted that the construction and arrangement of the present application shown in a plurality of different exemplary embodiments are only exemplary. Although only a few embodiments are described in detail in this disclosure, it should be readily understood by those who refer to this disclosure that many modifications are possible (e.g., the size, scale, structure, shape and proportion of various elements, and parameter values ​​(e.g., temperature, pressure, etc.), installation arrangement, use of materials, color, directional changes, etc.) without substantially departing from the novel teachings and advantages of the subject matter described in the application. For example, the element shown as integrally formed can be composed of multiple parts or elements, the position of the element can be inverted or otherwise changed, and the nature or number or position of the discrete element can be changed or changed. Therefore, all such modifications are intended to be included in the scope of the present invention. The order or sequence of any process or method steps can be changed or reordered according to alternative embodiments. In the claims, any "device plus function" clause is intended to cover the structure of performing the function described herein, and is not only structurally equivalent but also equivalent structure. Without departing from the scope of the present invention, other replacements, modifications, changes and omissions can be made in the design, operating conditions and arrangement of the exemplary embodiments. Therefore, the invention is not limited to a specific embodiment, but extends to several modifications still falling within the scope of the appended claims.

[0046] Additionally, in order to provide a concise description of exemplary embodiments, all features of an actual embodiment (ie, those features that are not relevant to the best mode presently contemplated for carrying out the invention or those that are not relevant to implementing the invention) may not be described.

[0047] It will be appreciated that in the development of any actual implementation, as in any engineering or design project, numerous implementation-specific decisions may be made. Such a development effort may be complex and time-consuming, but will be a routine task of design, fabrication, and production for those of ordinary skill having the benefit of this disclosure without undue experimentation.

[0048] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. An energy storage cascade heating system adapted to a new type of power system, comprising a unit module (100), characterized in that: Also includes, The primary heating module (200) comprises a main exhaust pipe (201), a primary steam supply branch (202), an absorption heat pump (203), and a primary exhaust pipe (204); A secondary heating module (300) includes a secondary steam supply branch (301), a peak heater (302), a secondary exhaust pipe (303), and a secondary recovery pipe (304); A water supply module (400) includes a hot water storage tank (403); The main exhaust steam pipe (201) is in communication with the unit module (100); the primary steam supply branch (202) and the secondary steam supply branch (301) are both in communication with the main exhaust steam pipe (201); the primary steam supply branch (202) and the secondary steam supply branch (301) supply steam to the absorption heat pump (203) and the peak heater (302) respectively; the secondary recovery pipe (304) is used to combine the heated exhaust steam of the primary heating module (200) with the exhaust steam of the secondary heating module (300) and then return them to the absorption heat pump (203).

2. The energy storage cascade heating and heat supply system adapted to the new power system as claimed in claim 1 is characterized by: The unit module (100) comprises a medium-pressure cylinder (101), a low-pressure cylinder (102), a generator (103), a condenser (106) and a condensate pump (107); the medium-pressure cylinder (101), the low-pressure cylinder (102) and the generator (103) are coaxially arranged; the exhaust steam of the low-pressure cylinder (102) is connected to the condenser (106); the drainage of the condenser (106) is connected to the condensate pump (107).

3. The energy storage cascade heating and heat supply system adapted to the new power system as claimed in claim 2 is characterized by: A connecting steam pipe (104) and a connecting branch pipe (105) are provided between the medium-pressure cylinder (101) and the low-pressure cylinder (102), and regulating valves are provided on the connecting steam pipe (104) and the connecting branch pipe (105).

4. The energy storage cascade heating and heat supply system adapted to the new power system as claimed in claim 3 is characterized by: The connecting steam pipe (104) is additionally provided with a main exhaust steam pipe (201) at the front end of the regulating valve; the input end of the main exhaust steam pipe (201) is connected to the exhaust steam of the intermediate pressure cylinder (101) through the connecting steam pipe (104); and the output end of the main exhaust steam pipe (201) is respectively connected to the input ends of the primary steam supply branch (202) and the secondary steam supply branch (301).

5. The energy storage cascade heating and heat supply system adapted to the new power system as claimed in claim 4 is characterized by: The absorption heat pump (203) is provided with a cold side and a hot side. The hot side of the absorption heat pump (203) is provided with two heaters, namely a first heater and a second heater. The output end of the first steam supply branch (202) is connected to the input end of the first heater.

6. The energy storage cascade heating and heat supply system adapted to the new power system as claimed in claim 5 is characterized by: The output end of the secondary steam supply branch (301) is connected to the steam inlet end of the peak heater (302), and the exhaust end of the peak heater (302) is provided with a secondary exhaust pipe (303), and the secondary exhaust pipe (303) is connected to the secondary recovery pipe (304).

7. The energy storage cascade heating and heat supply system adapted to the new power system as claimed in claim 6 is characterized by: The secondary recovery pipe (304) is in communication with the input end of the second heater of the absorption heat pump (203), and the output end of the first heater is in communication with the secondary recovery pipe (304).

8. The energy storage cascade heating and heat supply system adapted to the new power system as claimed in claim 7 is characterized by: The output end of the second heater is connected to the input end of the drain pipe (205), the output end of the first heater is connected to the drain pipe (205), and the output end of the drain pipe (205) is connected to the input end of the condensate pump (107).

9. The energy storage cascade heating and heat supply system adapted to the new power system as claimed in claim 8, characterized in that: The main exhaust pipe (201), the first-level steam supply branch (202), and the second-level steam supply branch (301) are all provided with a check valve, a regulating valve, and an isolation valve in sequence.

10. The energy storage cascade heating and heat supply system adapted to the new power system according to claim 9, characterized in that: The water supply module (400) further comprises a heating water return pipe (401), a connecting water pipe (402) and a water supply pipe (404); the heating water return pipe (401) is connected to the cold side of the absorption heat pump (203); the cold side of the absorption heat pump (203) is connected to the water inlet end of the peak heater (302); the drainage end of the peak heater (302) is connected to the hot water storage tank (403); and the drainage end of the hot water storage tank (403) is connected to the water supply pipe (404).

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