WO2021174862A1

WO2021174862A1 - Solar tower and trough combined power generation system

Info

Publication number: WO2021174862A1
Application number: PCT/CN2020/121428
Authority: WO
Inventors: 张�成
Original assignee: 广东海洋大学
Priority date: 2020-03-05
Filing date: 2020-10-16
Publication date: 2021-09-10
Also published as: ZA202110907B; CN111173697B; CN111173697A

Abstract

A solar tower and trough combined power generation system, comprising a trough-type heat collector (11), a tower-type heat collector (12), a preheater (21), a superheater (22), and a reheater (23). A heating pipe outlet of the trough-type heat collector (11) is connected to a heat transfer fluid inlet of the preheater (21); a heat transfer fluid outlet of the preheater (21) is connected to a heating pipe inlet of the trough-type heat collector (11); a heating pipe outlet of the tower-type heat collector (12) is separately connected to a heat transfer fluid inlet of the superheater (22) and a heat transfer fluid inlet of the reheater (23); a heat transfer fluid outlet of the superheater (22) and a heat transfer fluid outlet of the reheater (23) are connected to a heating pipe inlet of the tower-type heat collector (12). By using both the trough-type heat collector (11) and the tower-type heat collector (12) which work in respective optimum working temperature intervals, the system efficiency and the site utilization ratio of a tower-type mirror field are improved. Segmented heating of a working medium is implemented, and the flows of the heat transfer fluids in heat exchangers can be independently adjusted as needed, so that the heat exchange temperature difference and exergy loss are reduced and the power generation efficiency is improved.

Description

Solar tower trough combined power generation system

This application claims the priority of a Chinese patent application filed with the Chinese Patent Office on March 5, 2020, the application number is 202010146473.8, and the invention title is "a solar tower and trough combined power generation system", the entire content of which is incorporated into this application by reference middle.

Technical field

The invention relates to the technical field of solar photothermal power generation, in particular to a solar tower and trough combined power generation system.

Background technique

With the emergence of fossil energy consumption and environmental pollution, solar energy is widely regarded as the clean energy that has the most potential to replace traditional fossil energy in the future. Solar thermal power generation usually uses heat collectors to condense and collect heat to generate electricity, and use mirrors to condense sunlight to a receiver for absorbing solar energy, generate heat and transfer it to synthetic oil, molten salt, or air. fluid. Then, the heat transfer fluid directly or indirectly provides heat to the power cycle system. Compared with solar photovoltaic power generation, solar thermal power generation has attracted more and more attention due to its high energy density, stable power generation, good grid compatibility, and easy integration with existing thermal power plants. The existing solar thermal power plants all adopt a single collector structure: solar trough power generation or solar tower power generation.

Solar trough-type power generation technology uses a trough-shaped parabolic reflector. The reflector uses a single-axis tracking method to track the sun during the day. The reflector reflects the sunlight and concentrates it on the heating tube located at the focal line. The heat transfer fluid flows through the heating tube and absorbs the heat generated by the concentrated sunlight, and supplies it to the power generation system. The structure diagram of the existing solar trough-type power generation system is shown in Figure 1. The circulation loop of the heat transfer fluid is: after the heat transfer fluid is heated by the trough collector 11, a part of it passes through the superheater 22 and preheated in turn The heat exchanger 21 exchanges heat with the Rankine cycle passing through the heat exchanger 22 and the preheater 21 and then flows back to the trough collector 11, and the other part passes through the reheater 23 and exchanges heat with the Rankine cycle passing through the reheater 23 Then it flows back to the trough collector 11.

Solar tower power generation technology is a solar power generation technology that uses a receiver located on the top of a tall tower to receive concentrated sunlight. It uses a large number of movable solar mirrors (called heliostats), and each heliostat is equipped with a tracking mechanism to accurately reflect the sunlight to the receiver on the top of the tower in real time. The tracking mechanism is a dual-axis tracking (from east to west, up and down) to track the sun. The receiver absorbs concentrated solar radiation to convert solar energy into heat, which is then transferred to the thermal cycle system by the heat transfer fluid for power generation. The structure diagram of the existing solar tower power generation system is shown in Figure 2. The circulation loop of the heat transfer fluid is: after the heat transfer fluid is heated by the tower collector 12, a part of it passes through the superheater 22 and preheated in turn The heat exchanger 21 exchanges heat with the Rankine cycle passing through the heat exchanger 22 and the preheater 21 and then flows back to the tower collector 12, and the other part passes through the reheater 23 and exchanges heat with the Rankine cycle passing through the reheater 23 Then flow back to the tower collector 12.

Solar trough power generation technology is the most mature and commercialized technology, but it has the following shortcomings: the concentration ratio is relatively small, the heat collection temperature of the receiver is relatively low, and the efficiency of solar thermal power generation is relatively low. Solar tower power generation technology, because the top of the tower can condense a large amount of energy when a large number of heliostats are used, and the receiver can reach a very high temperature, so it has the advantage of high efficiency of solar thermal power generation and can be applied on a large scale, but At the same time, it has the disadvantages of high investment cost, high system complexity, large heat exchange temperature difference of the heat absorber, and high energy consumption of the molten salt insulation system.

In addition, the existing solar tower power generation technology and solar trough power generation technology both have a large temperature difference and large temperature difference between the heat transfer fluid and the Rankine cycle heat exchange process.

Damage problem. This is because, for trough power generation and tower power generation technologies, during the heat exchange process between the heat transfer fluid and the Rankine cycle working fluid, as shown in Figure 3, the Rankine cycle working fluid has a phase change, while the heat transfer fluid does not Phase change, so there is a large heat transfer temperature difference in the heat transfer process, and the heat transfer

The problem of greater damage.

In the existing solar trough power generation system shown in Figure 1 and the solar tower power generation system structure shown in Figure 2, the heat transfer fluid can only flow through each heat exchanger (preheater 21) at a constant mass flow rate. , Superheater 22 and reheater 23) to achieve heat exchange, as shown in Figure 4, in _{the case that the pinch temperature difference ΔT min is} fixed, if the mass flow rate of the heat transfer fluid is increased to reduce the slope of the heat transfer fluid curve , While reducing the average heat transfer temperature difference in the evaporation section, it also increases the average heat transfer temperature difference in the preheating section; similarly, if the flow rate of the heat transfer fluid is reduced to increase the slope of the heat transfer fluid curve, it will decrease The average heat exchange temperature difference in the preheating section also increases the average heat exchange temperature difference in the evaporation section, so the large temperature difference and the large

The problem of damage is always unavoidable.

Summary of the invention

The purpose of the present invention is to provide a solar tower and trough combined power generation system, which overcomes the large temperature difference and large temperature difference caused by the heat transfer fluid that can only flow through the heat exchangers at a constant mass flow rate in the prior art.

The problem of damage.

To achieve this goal, the present invention adopts the following technical solutions:

A solar tower and trough combined power generation system, including: a heat collection device and a heat exchange device;

The heat collection device includes: a trough type heat collector and a tower type heat collector;

The heat exchange device includes: a preheater, a superheater, and a reheater, and the preheater or the superheater is also combined with an evaporator;

The heating pipe outlet of the trough collector is connected to the heat transfer fluid inlet of the preheater through a first pipe; the heat transfer fluid outlet of the preheater is connected to the trough collector through a second pipe. The inlet of the heating pipe of the heater is connected;

The heating pipe outlet of the tower collector is connected to the heat transfer fluid inlet of the superheater and the heat transfer fluid inlet of the reheater through a third pipe; the heat transfer fluid outlet of the superheater and The heat transfer fluid outlet of the reheater is respectively connected to the heating pipe inlet of the tower collector through a fourth pipe.

Optionally, it also includes a heat storage device;

The heat storage device includes: a low temperature heat storage tank, a medium temperature heat storage tank, and a high temperature heat storage tank;

The inlet of the low-temperature heat storage tank is connected to the second pipeline through a first valve, and the outlet of the low-temperature heat storage tank is connected to the second pipeline through a second valve;

The inlet of the high temperature heat storage tank is connected to the third pipeline through a third valve, and the outlet of the high temperature heat storage tank is connected to the third pipeline through a fourth valve;

The first inlet of the medium temperature heat storage tank is connected to the first pipe through a fifth valve; the first outlet of the medium temperature heat storage tank is connected to the first pipe through a sixth valve; the medium temperature heat storage tank The second inlet of the heat tank is connected to the fourth pipe through a fifth valve; the second outlet of the medium-temperature heat storage tank is connected to the fourth pipe through a sixth valve.

Optionally, it also includes a steam turbine, and the steam turbine includes a high-pressure cylinder and a medium and low-pressure cylinder;

The working fluid outlet of the superheater is connected to the working fluid inlet of the high-pressure cylinder;

The working fluid outlet of the high-pressure cylinder is connected to the working fluid inlet of the reheater;

The working fluid outlet of the reheater is connected with the working fluid inlet of the medium and low pressure cylinder;

The first working fluid outlet of the middle and low pressure cylinder is connected to the inlet of the deaerator, and the second working fluid outlet of the middle and low pressure cylinder is connected to the inlet of the deaerator through a condenser;

The outlet of the deaerator is connected with the working fluid inlet of the preheater,

The working fluid outlet of the preheater is connected with the working fluid inlet of the superheater.

Optionally, the design value of the outlet temperature of the heat transfer fluid of the trough collector is not equal to the design value of the inlet temperature of the heat transfer fluid of the tower collector.

Optionally, the heat transfer fluid flowing through the heat collection device and the heat exchange device includes: synthetic oil, molten salt or air; the Rankine cycle working fluid flowing through the heat exchange device includes: water, CO2 or organic working fluid.

The present invention also proposes another solar tower and trough combined power generation system, including: a heat collection device, a heat storage device and a heat exchange device;

The outlet of the heating pipe of the trough collector is connected to the first inlet of the medium-temperature heat storage tank through a first pipe; the first outlet of the medium-temperature heat storage tank is connected to the preheater through a second pipe The heat transfer fluid inlet of the preheater is connected; the heat transfer fluid outlet of the preheater is connected to the inlet of the low temperature heat storage tank through a third pipe; the outlet of the low temperature heat storage tank is connected to the tank through a fourth pipe The inlet of the heating tube of the heat collector is connected;

The outlet of the heating pipe of the tower collector is connected to the inlet of the high temperature heat storage tank through a fifth pipe; the outlet of the high temperature heat storage tank is connected to the heat transfer fluid inlet of the superheater through a sixth pipe Are respectively connected to the heat transfer fluid inlet of the reheater; the heat transfer fluid outlet of the superheater and the heat transfer fluid outlet of the reheater respectively pass through the seventh pipe and the second heat storage tank The inlet is connected; the second outlet of the medium-temperature heat storage tank is connected to the heating tube inlet of the tower collector through an eighth pipe.

Compared with the prior art, the embodiments of the present invention have the following beneficial effects:

1) The embodiment of the present invention uses both a tower collector and a trough collector. The trough collector is used to collect the heat at a lower temperature, and the tower collector is used to collect the heat at a higher temperature, so that the tower The trough collector and the trough collector can work in their respective optimal operating temperature ranges, which is beneficial to improve the efficiency of the system. The addition of the trough collector can also increase the utilization rate of the tower mirror field and reduce the system cost. .

2) The embodiment of the present invention uses tower collectors and trough collectors to realize the segmented heating of the Rankine cycle working fluid; based on the segmented heating method, the mass flow of the heat transfer fluid in each heat exchanger It can be adjusted separately according to the needs, so as to reduce the heat exchange temperature difference of each heat exchanger and reduce the heat exchange process

Loss and improve the power generation efficiency of power plants.

Description of the drawings

In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only These are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative labor.

Figure 1 is a structural diagram of an existing solar trough-type power generation system;

Figure 2 is a structural diagram of an existing solar tower power generation system;

Figure 3 is a schematic diagram of heat transfer of an existing tower power generation system and a trough power generation system;

4 is a schematic diagram of heat transfer when the mass flow rate of the heat transfer fluid is changed in the prior art;

Fig. 5 is a structural diagram of a solar tower and trough combined power generation system provided by the first embodiment of the present invention;

6 is a schematic diagram of heat transfer when the mass flow rate of the heat transfer fluid is changed according to an embodiment of the present invention;

FIG. 7 is another schematic diagram of heat transfer when the mass flow rate of the heat transfer fluid is changed according to an embodiment of the present invention;

Fig. 8 is a structural diagram of a solar tower-tank combined power generation system provided by the second embodiment of the present invention.

【Illustration】

Heat collector 10: trough collector 11, tower collector 12;

Heat exchange device 20: preheater 21, superheater 22, reheater 23;

Heat storage device 30: low temperature heat storage tank 31, medium temperature heat storage tank 32, high temperature heat storage tank 33;

Steam turbine 40: high pressure cylinder 41, medium and low pressure cylinder 42, condenser 43, deaerator 44.

Detailed ways

In order to enable those skilled in the art to better understand the solutions of the embodiments of the present invention, the technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described implementation The examples are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work should fall within the protection scope of the embodiments of the present invention.

The terms "including" and "having" in the description and claims of the embodiments of the present invention and the above-mentioned drawings and any variations thereof are intended to cover non-exclusive inclusions, for example, a process that includes a series of steps or units, The method, system, product, or device need not be limited to those clearly listed steps or units, but may include other steps or units that are not clearly listed or are inherent to these processes, methods, products, or devices.

The core idea of the present invention is: by using multi-stage heat storage to achieve multiple heat source temperatures and multiple heat transfer fluid flow rates, to achieve segmented heating of the preheating section, evaporation section, and overheating section, thereby solving the problem of heat transfer fluid and Rankine cycle. The large temperature difference and large

Damage problem.

Referring to Fig. 5, an embodiment of the present invention provides a solar tower and trough combined power generation system, including: a heat collection device 10 and a heat exchange device 20;

The heat collection device 10 includes: a trough type heat collector 11 and a tower type heat collector 12.

The heat exchange device 20 includes: a preheater 21, a superheater 22, and a reheater 23, and the preheater 21 or the superheater 22 also has an evaporator function.

The heating pipe outlet of the trough collector 11 is connected to the heat transfer fluid inlet of the preheater 21 through the first pipe; the heat transfer fluid outlet of the preheater 21 is heated by the trough heat collector 11 through the second pipe The pipe inlet is connected.

Based on this part of the structure, the heat transfer fluid flowing out of the heating tube of the trough collector 11 first flows into the preheater 21 through the first pipe, and exchanges heat with the Rankine cycle working fluid flowing through the preheater 21. Then the second pipe enters into the heating tube of the trough collector 11 to absorb heat, thereby forming a first heat transfer fluid circulation loop.

The outlet of the heating tube of the tower collector 12 is respectively connected to the heat transfer fluid inlet of the superheater 22 and the heat transfer fluid inlet of the reheater 23 through a third pipe; the heat transfer fluid outlet of the superheater 22 and the reheater 23 The outlets of the heat transfer fluid are respectively connected to the inlets of the heating pipes of the tower collector 12 through the fourth pipe.

Based on this structure, the heat transfer fluid flowing out of the heating tube of the tower collector 12 first passes through the third pipe. The reheater 23 exchanges heat with the Rankine cycle working fluid flowing through the reheater 23. After the heat exchange is completed, it enters the heating tube of the tower collector 12 through the fourth pipe to absorb heat, thereby forming a second heat transfer fluid Circulation loop.

In this embodiment, both the tower collector 12 and the trough collector 11 are used; among them, the trough collector 11 is used to collect heat at a lower temperature, and the heat transfer fluid flowing through its heating tube The temperature T1 is heated to the temperature T2. The heat transfer fluid is used to exchange heat with the Rankine cycle working fluid flowing through the preheater 21; The heat transfer fluid of the tube is heated from the temperature T2 ′ to the temperature T3, and the heat transfer fluid is used to exchange heat with the Rankine cycle working fluid flowing through the heat exchanger 22.

It should be noted that the design value T2 of the heat transfer fluid outlet temperature of the trough collector and the design value T2' of the heat transfer fluid inlet temperature of the tower collector can be equal or unequal, and can be customized according to needs. design. When reasonably adjusting the mass flow rate of the heat transfer fluid in each heat exchanger, if T2 and T2' are equal, the heat transfer curve shown in Figure 6 can be obtained, and if T2 and T2' are not equal, the heat transfer curve shown in Figure 7 can be obtained. In fact, compared with the two cases, when T2 and T2' are not equal, the heat exchange temperature difference is smaller, and the heat exchange

The loss is also smaller.

Therefore, this embodiment can not only enable the tower collector 12 and the trough collector 11 to work in their respective optimal operating temperature ranges, but also improve the system efficiency. The addition of the trough collector 11 can also improve The field utilization rate of the tower mirror field reduces the system cost. Moreover, the segmented heating of the preheating section, the evaporation section and the superheating section of the heat exchange part is realized; based on the segmented heating method, each heat exchanger (preheater 21, superheater 22, reheater 23) The mass flow rate of the heat transfer fluid (as shown in q1, q2, and q3 in Figure 5) can be adjusted as needed.

Further, by reasonably adjusting the mass flow rate of the heat transfer fluid in each heat exchanger, as shown in Figures 6 and 7 of the heat transfer comparison schematic diagram between the embodiment of the present invention and the existing traditional solution, the heat transfer of each heat exchanger can be reduced. Heat exchange temperature difference, reduce the heat exchange process

Loss and improve the power generation efficiency of power plants. At the same time, a reasonable heat transfer fluid temperature can also be selected to reduce the heat transfer process in the reheater 23.

damage.

In practical applications, the heat transfer fluid temperature at the heat transfer fluid inlet and the heat transfer fluid outlet of each heat exchanger can be preset according to actual needs, and the flow quality of the heat transfer fluid of each heat exchanger can be adjusted accordingly (if To increase the slope of the heat transfer fluid curve in the current heat exchanger, reduce the mass flow of the corresponding part of the heat transfer fluid, or increase it on the contrary, so as to reduce the heat exchange temperature difference of each heat exchanger and the heat exchange process

The purpose of loss.

It should be noted that the Rankine cycle working fluid can be water, or other media, such as CO2, organic working fluid, etc.; the heat transfer fluid can be synthetic oil, molten salt or air, etc., and the specifics are not limited.

In addition, the power generation system of this embodiment may further include a heat storage device 30 which includes a low temperature heat storage tank 31, a medium temperature heat storage tank 32 and a high temperature heat storage tank 33.

Among them, the low-temperature heat storage tank 31 includes an inlet and an outlet. The inlet is connected to the second pipe through a first valve, and the outlet is connected to the second pipe through a second valve to store low-temperature heat transfer fluid.

The high-temperature heat storage tank 33 includes an inlet and an outlet. The inlet is connected to the third pipe through a third valve, and the outlet is connected to the third pipe through a fourth valve, and is used to store high-temperature heat transfer fluid.

The medium temperature heat storage tank 32 includes two inlets and two outlets. The first inlet is connected to the first pipe through a fifth valve, and the first outlet is connected to the first pipe through a sixth valve; and the second inlet is connected to the first pipe through a fifth valve. It is connected to the fourth pipe, and its second outlet is connected to the fourth pipe through a sixth valve for storing medium-temperature heat transfer fluid.

The application of the above-mentioned low temperature heat storage tank 31, medium temperature heat storage tank 32 and high temperature heat storage tank 33 realizes three-stage heat storage and can automatically match the heat transfer fluid in the tower collector 12 and the trough collector 11 The mass flow rate also helps to flexibly adjust the mass flow rate of the heat transfer fluid flowing through each heat exchanger.

In addition, this embodiment can use the medium-temperature heat storage tank 32 to buffer the heat transfer fluid and adjust the flow rate of the heat transfer fluid to stabilize the heat exchange temperature and flow rate in the heat exchanger, which is conducive to the stable power generation of the system; the use of trough collectors 11 Collect medium-temperature heat transfer fluid to provide low-cost technology for system startup and heat preservation and anti-condensation work.

As shown in FIG. 5, the power generation system of this embodiment further includes a steam turbine 40, and the steam turbine 40 includes a high pressure cylinder 41 and a medium and low pressure cylinder 42.

Among them, the working medium outlet of the superheater 22 is connected with the working medium inlet of the high-pressure cylinder 41; the working medium outlet of the high-pressure cylinder 41 is connected with the working medium inlet of the reheater 23; the working medium outlet of the reheater 23 is connected with the medium and low pressure cylinder 42 The first working medium outlet of the medium and low pressure cylinder 42 is connected to the inlet of the deaerator 44, and the second working medium outlet of the medium and low pressure cylinder 42 is connected to the inlet of the deaerator 44 through the condenser 43; The outlet of the oxygenator 44 is connected to the working fluid inlet of the preheater 21, and the working fluid outlet of the preheater 21 is connected to the working fluid inlet of the superheater 22.

It should be noted that both the high-pressure cylinder and the medium and low-pressure cylinders may have steam extraction for heating the feedwater and deaerator. However, in order to briefly describe the solution of the embodiment of the present invention, the schematic diagram provided in FIG. The steam extraction port. In fact, both the high pressure cylinder and the medium and low pressure cylinder may have more other extraction steam outlets, which are not limited by the present invention.

The working fluid of the Rankine cycle is as follows: the preheated and steam-like Rankine cycle working fluid enters the superheater 22 and heats it into superheated steam. After the superheated steam does work in the high-pressure cylinder 41 of the steam turbine 40, low-pressure and low-temperature steam is formed. Enters the reheater 23, the reheater 23 reheats this part of the steam into high-temperature steam. The high-temperature steam enters the middle and low pressure cylinder 42 of the steam turbine 40 to continue to perform work. The liquid enters the deaerator 44; after the deaerator 44 performs deoxygenation, it enters the preheater 21 for preheating and vaporization and then enters the superheater 22, thereby forming a circulation loop of the Rankine cycle working fluid.

It should be noted that the circulation side structure of the Rankine cycle working fluid (including the internal connection structure of the heat exchange device 20 and the steam turbine 40) is not limited to the structure shown in FIG. 5, and can be flexibly adjusted according to the actual situation. limit.

In summary, the embodiment of the present invention applies two different types of heat collectors and three-stage heat storage, which can realize the optimization strategy of real-time control of heat storage, heat transfer fluid flow, system operation mode, etc., and improve the stability of the system. Sex and flexibility.

Example two

Referring to FIG. 8, an embodiment of the present invention provides another solar tower and trough combined power generation system, which includes a heat collection device 10, a heat storage device 30 and a heat exchange device 20.

The heat collecting device 10 includes: a trough type heat collector 11 and a tower type heat collector 12.

The heat storage device 30 includes a low temperature heat storage tank 31, a medium temperature heat storage tank 32 and a high temperature heat storage tank 33. Among them, the low-temperature heat storage tank 31 and the high-temperature heat storage tank 33 both include one inlet and one outlet, and the medium-temperature heat storage tank 32 includes two inlets and two outlets.

The outlet of the heating pipe of the trough collector 11 is connected to the first inlet of the intermediate temperature heat storage tank 32 through the first pipe; the first outlet of the intermediate temperature heat storage tank 32 is connected to the heat transfer fluid of the preheater 21 through the second pipe The inlet is connected; the heat transfer fluid outlet of the preheater 21 is connected to the inlet of the low-temperature heat storage tank 31 through the third pipe; the outlet of the low-temperature heat storage tank 31 is connected to the heating pipe inlet of the trough collector 11 through the fourth pipe Connected.

The outlet of the heating pipe of the tower collector 12 is connected to the inlet of the high-temperature heat storage tank 33 through the fifth pipe; the outlet of the high-temperature heat storage tank 33 is connected to the heat transfer fluid inlet of the superheater 22 and the reheater through the sixth pipe The heat transfer fluid inlets of 23 are respectively connected; the heat transfer fluid outlet of the superheater 22 and the heat transfer fluid outlet of the reheater 23 are respectively connected to the second inlet of the intermediate temperature heat storage tank 32 through the seventh pipe; the intermediate temperature heat storage tank 32 The second outlet is connected to the inlet of the heating tube of the tower collector 12 through the eighth pipe.

The difference from the first embodiment is that each heat storage tank in the second embodiment is completely used as a buffer device between the heat collection device 10 and the heat exchange device 20. However, the second embodiment also implements two heat transfer fluid circulation loops to realize the segmented heating of the Rankine cycle working fluid. The implementation principle is the same as that of the first embodiment, and will not be repeated here.

As mentioned above, the above embodiments are only used to illustrate the technical solutions of the present invention, but not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: The technical solutions recorded in the embodiments are modified, or some of the technical features are equivalently replaced; these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

A solar tower and trough combined power generation system, which is characterized by comprising: a heat collection device and a heat exchange device;

The heat collection device includes: a trough type heat collector and a tower type heat collector;

The heat exchange device includes: a preheater, a superheater, and a reheater, and the preheater or the superheater is also combined with an evaporator;

The heating pipe outlet of the trough collector is connected to the heat transfer fluid inlet of the preheater through a first pipe; the heat transfer fluid outlet of the preheater is connected to the trough collector through a second pipe. The inlet of the heating pipe of the heater is connected;

The heating pipe outlet of the tower collector is connected to the heat transfer fluid inlet of the superheater and the heat transfer fluid inlet of the reheater through a third pipe; the heat transfer fluid outlet of the superheater and The heat transfer fluid outlet of the reheater is respectively connected to the heating tube inlet of the tower collector through a fourth pipe.
The solar tower and trough combined power generation system according to claim 1, further comprising a heat storage device;

The heat storage device includes: a low temperature heat storage tank, a medium temperature heat storage tank, and a high temperature heat storage tank;

The inlet of the low-temperature heat storage tank is connected to the second pipeline through a first valve, and the outlet of the low-temperature heat storage tank is connected to the second pipeline through a second valve;

The inlet of the high-temperature heat storage tank is connected to the third pipeline through a third valve, and the outlet of the high-temperature heat storage tank is connected to the third pipeline through a fourth valve;

The first inlet of the medium temperature heat storage tank is connected to the first pipe through a fifth valve; the first outlet of the medium temperature heat storage tank is connected to the first pipe through a sixth valve; the medium temperature heat storage tank The second inlet of the heat tank is connected to the fourth pipe through a fifth valve; the second outlet of the medium-temperature heat storage tank is connected to the fourth pipe through a sixth valve.
The solar tower and trough combined power generation system according to claim 1 or 2, further comprising a steam turbine, the steam turbine comprising a high pressure cylinder and a medium and low pressure cylinder;

The working fluid outlet of the superheater is connected to the working fluid inlet of the high-pressure cylinder;

The working fluid outlet of the high-pressure cylinder is connected to the working fluid inlet of the reheater;

The working fluid outlet of the reheater is connected with the working fluid inlet of the medium and low pressure cylinder;

The first working fluid outlet of the middle and low pressure cylinder is connected to the inlet of the deaerator, and the second working fluid outlet of the middle and low pressure cylinder is connected to the inlet of the deaerator through a condenser;

The outlet of the deaerator is connected with the working fluid inlet of the preheater,

The working fluid outlet of the preheater is connected with the working fluid inlet of the superheater.
The solar tower and trough combined power generation system according to claim 1 or 2, wherein the design value of the outlet temperature of the heat transfer fluid of the trough collector is equal to the inlet temperature of the heat transfer fluid of the tower collector. The design values are not equal.
The solar tower and trough combined power generation system according to claim 1, wherein the heat transfer fluid flowing through the heat collection device and the heat exchange device includes: synthetic oil, molten salt or air; The Rankine cycle working fluid of the heat exchange device includes: water, CO2 or organic working fluid.
A solar tower and trough combined power generation system, which is characterized by comprising: a heat collection device, a heat storage device and a heat exchange device;

The heat collection device includes: a trough type heat collector and a tower type heat collector;

The heat storage device includes: a low temperature heat storage tank, a medium temperature heat storage tank, and a high temperature heat storage tank;

The heat exchange device includes: a preheater, a superheater, and a reheater, and the preheater or the superheater is also combined with an evaporator;

The outlet of the heating pipe of the trough collector is connected to the first inlet of the medium-temperature heat storage tank through a first pipe; the first outlet of the medium-temperature heat storage tank is connected to the preheater through a second pipe The heat transfer fluid inlet of the preheater is connected; the heat transfer fluid outlet of the preheater is connected to the inlet of the low-temperature heat storage tank through a third pipe; the outlet of the low-temperature heat storage tank is connected to the tank through a fourth pipe The inlet of the heating pipe of the heat collector is connected;

The outlet of the heating pipe of the tower collector is connected to the inlet of the high temperature heat storage tank through a fifth pipe; the outlet of the high temperature heat storage tank is connected to the heat transfer fluid inlet of the superheater through a sixth pipe Are respectively connected to the heat transfer fluid inlet of the reheater; the heat transfer fluid outlet of the superheater and the heat transfer fluid outlet of the reheater respectively pass through the seventh pipe and the second heat storage tank The inlet is connected; the second outlet of the medium-temperature heat storage tank is connected to the heating tube inlet of the tower collector through an eighth pipe.
The solar tower and slot combined power generation system according to claim 6, further comprising a steam turbine, the steam turbine comprising a high-pressure cylinder and a medium-low pressure cylinder;

The working fluid outlet of the superheater is connected to the working fluid inlet of the high-pressure cylinder;

The working fluid outlet of the high-pressure cylinder is connected to the working fluid inlet of the reheater;

The working fluid outlet of the reheater is connected with the working fluid inlet of the medium and low pressure cylinder;

The first working fluid outlet of the middle and low pressure cylinder is connected to the inlet of the deaerator, and the second working fluid outlet of the middle and low pressure cylinder is connected to the inlet of the deaerator through a condenser;

The outlet of the deaerator is connected to the working fluid inlet of the preheater;

The working fluid outlet of the preheater is connected with the working fluid inlet of the superheater.
The solar tower and trough combined power generation system according to claim 6, wherein the design value of the outlet temperature of the heat transfer fluid of the trough collector is equal to the design value of the inlet temperature of the heat transfer fluid of the tower collector. not equal.
The solar tower and trough combined power generation system according to claim 6, wherein the heat transfer fluid flowing through the heat collection device and the heat exchange device comprises: synthetic oil, molten salt or air; The Rankine cycle working fluid of the heat exchange device includes: water, CO2 or organic working fluid.