Power generation system for realizing zero discharge of waste water of coal-fired unit by utilizing photovoltaic waste heat

Abstract

The utility model relates to the technical field of power generation, in particular to a power generation system for realizing zero discharge of waste water of a coal-fired unit by utilizing photovoltaic waste heat, which comprises a spectrum frequency division device, a photovoltaic power generation device, a light condensation and heat collection device and the coal-fired unit, the spectrum frequency division equipment is used for performing spectrum frequency division processing on sunlight to obtain light waves of a first wave band and light waves of a second wave band, transmitting the light waves of the first wave band to the photovoltaic power generation equipment and transmitting the light waves of the second wave band to the light condensation and heat collection equipment; the coal-fired power generation unit comprises a bypass flue, the light-gathering heat-collecting equipment is further connected with the bypass flue, and the light-gathering heat-collecting equipment is used for converting light energy carried by the light waves of the second wave band into heat energy and heating flue gas in the bypass flue by using the heat energy so as to provide heat energy for high-salinity wastewater treatment; the technical problems that an existing power generation mode is low in solar energy utilization efficiency and heat energy of high-salinity wastewater treatment under the deep peak regulation working condition is insufficient can be solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of power generation, and in particular to a power generation system for realizing zero discharge of coal-fired unit wastewater by utilizing photovoltaic waste heat. BACKGROUND

[0002] In the existing power industry, a coal-fired complementary scheduling mode of coal-fired generating units and photovoltaic power generation equipment is usually used for power generation; wherein, in the period of sufficient solar energy, the photovoltaic power generation equipment is usually used to convert the light energy carried by sunlight into electrical energy, and at this time the coal-fired generating unit enters a deep peak shaving state; when entering the period of insufficient solar energy, the coal-fired generating unit is usually used for power generation, and at this time the coal-fired generating unit enters a high-power consumption state; in actual application, although the coal-fired complementary scheduling mode of coal-fired generating units and photovoltaic power generation equipment has the advantages of improving energy utilization efficiency and enhancing power generation reliability, etc., but in actual operation, there are the following application difficulties:

[0003] Firstly, although the photovoltaic power generation equipment can utilize solar energy, it can only utilize the visible light and near-infrared light with a wavelength of 400nm-1100nm in the sunlight, resulting in waste of the remaining wavelength of solar energy.

[0004] Secondly, the working process of the coal-fired generating unit will produce high-salinity wastewater, and the existing technology usually uses bypass flue gas evaporation technology to introduce the high-temperature flue gas discharged by the coal-fired generating unit into a bypass flue, and then uses the high-temperature flue gas in the bypass flue as a heat source to heat the wastewater to evaporate the wastewater, but when the coal-fired generating unit is in a deep peak shaving state, the heat source of the unit is tight, and cannot produce high-temperature flue gas meeting the demand, which will eventually result in that the high-salinity wastewater cannot be effectively treated. CONTENT OF THE UTILITY MODEL

[0005] Therefore, the purpose of the present application is to provide a power generation system to solve the technical problems of insufficient utilization of solar energy and ineffective treatment of high-salinity wastewater in the existing power generation mode.

[0006] The present application provides a power generation system, which comprises a spectrum splitting device, a photovoltaic power generation equipment, a light condensation and heat collection equipment and a coal-fired generating unit;

[0007] The spectrum splitting device is connected with the photovoltaic power generation equipment and the light condensation and heat collection equipment, respectively;

[0008] The spectrum splitting device is used for performing spectrum splitting processing on sunlight to obtain light waves of a first wavelength band and light waves of a second wavelength band, and transmitting the light waves of the first wavelength band to the photovoltaic power generation equipment and sending the light waves of the second wavelength band to the light condensation and heat collection equipment;

[0009] The coal-fired power generator set comprises a bypass flue, and the light-gathering and heat-collecting device is further connected with the bypass flue, and the light-gathering and heat-collecting device is used for converting the light energy carried by the light wave of the second wave band into heat energy, and heating the flue gas in the bypass flue to obtain high-temperature flue gas.

[0010] Preferably, the light-gathering and heat-collecting device comprises a light energy conversion device and a heat-collecting device, a medium output end of the light energy conversion device is connected with a heat-collecting input end of the heat-collecting device, and a heat-collecting output end of the heat-collecting device is connected with a first medium input end of the light energy conversion device to form a first circulation loop.

[0011] The light energy conversion device is further connected with the light spectrum frequency division device, and is used for converting the light energy carried by the light wave of the second wave band into heat energy, and heating the heat exchange medium in the first circulation loop by the heat energy.

[0012] The heat-collecting device can heat the flue gas in the bypass flue by the heated heat exchange medium to obtain high-temperature flue gas.

[0013] Preferably, the light-gathering and heat-collecting device further comprises a first valve, and the first valve is arranged between the medium output end and the heat-collecting input end.

[0014] The first valve is used for adjusting whether the first circulation loop is conducted or not.

[0015] Preferably, the light-gathering and heat-collecting device further comprises a second valve, one end of the second valve is connected with a position between the first valve and the medium output end, and the other end is connected with a second medium input end of the light energy conversion device to form a second circulation loop.

[0016] The second valve is used for adjusting whether the second circulation loop is conducted or not.

[0017] Preferably, the light-gathering and heat-collecting device further comprises a driving device, and the driving device is arranged between the first valve and the medium output end.

[0018] The driving device is used for driving the heat exchange medium in the first circulation loop or the second circulation loop to flow in a preset flow direction.

[0019] Preferably, the light-gathering and heat-collecting device further comprises a heat storage device, and the heat storage device is connected between the driving device and the medium output end.

[0020] The heat storage device is composed of a storage tank, and is used for storing the heat exchange medium.

[0021] Preferably, when the power generation system is in the deep peak-shaving mode, the first valve is opened, and the first circulation loop is in the on state.

[0022] The spectral splitting device splits the sunlight into second-band light waves, and sends the second-band light waves to the light energy conversion device.

[0023] The light energy conversion device converts the light energy carried by the second-band light waves into heat energy, and heats the heat exchange medium flowing in the first circulation loop, so that the temperature of the heat exchange medium in the first circulation loop is not lower than a first preset temperature.

[0024] The heat exchange medium carrying the heat energy is delivered to the heat collecting device through the first circulation loop, so that the heat collecting device heats the flue gas delivered through the bypass flue by using the heat energy carried by the heat exchange medium, to obtain high-temperature flue gas.

[0025] Preferably, before the power generation system enters the deep peak-shaving mode, the first valve is closed, the second valve is opened, and the second circulation loop is in the on state within a preset time period.

[0026] The spectral splitting device splits the sunlight into second-band light waves, and sends the second-band light waves to the light energy conversion device.

[0027] The light energy conversion device converts the light energy carried by the second-band light waves into heat energy, and preheats the heat exchange medium flowing in the second circulation loop until the heat exchange medium reaches a second preset temperature.

[0028] Preferably, the coal-fired power generating unit further comprises a main flue and an air preheater, and the air preheater is arranged in the main flue.

[0029] The air preheater is used to preheat the air to a third preset temperature by the heat of the flue gas delivered through the main flue, and then send the air into the coal-fired power generating unit, so as to reduce the temperature of the flue gas.

[0030] Preferably, the coal-fired power generating unit further comprises a soot blowing device, and the soot blowing device is also arranged in the main flue; the soot blowing device is used to blow the soot of the flue gas delivered through the main flue or the bypass flue, respectively.

[0031] Beneficial effects:

[0032] The application provides a power generation system, which comprises a spectrum splitting device, a photovoltaic power generation device, a light condensation and heat collection device and a coal-fired power generation unit; the spectrum splitting device is connected with the photovoltaic power generation device and the light condensation and heat collection device respectively; the spectrum splitting device is used for performing spectrum splitting processing on sunlight to obtain light waves of a first wave band and light waves of a second wave band, and transmitting the light waves of the first wave band to the photovoltaic power generation device and sending the light waves of the second wave band to the light condensation and heat collection device; the coal-fired power generation unit comprises a bypass flue, and the light condensation and heat collection device is further connected with the bypass flue; the light condensation and heat collection device is used for converting light energy carried by the light waves of the second wave band into heat energy, and heating flue gas in the bypass flue to obtain high-temperature flue gas.

[0033] As can be seen, the power generation system provided by the application is characterized in that high power of the photovoltaic power generation device is accompanied by deep peak regulation of the coal-fired power generation unit, and at this time, the remaining solar heat energy is matched with the current situation that a large amount of heat is required for drying of low-load high-salt wastewater of the coal-fired power generation unit. At low load, the heat energy indirectly generated by the light waves of the second wave band is used to heat the flue gas to obtain high-temperature flue gas, thereby effectively realizing zero discharge of wastewater.

[0034] In addition, the application does not hinder the normal operation of the original photovoltaic power generation device and the coal-fired power generation unit, and uses the characteristics that the high-load interval of the photovoltaic power generation device corresponds to the low-load interval of the coal-fired power generation unit to increase the safety of the operation of removing high-salt wastewater of the coal-fired power generation unit, so that high-grade light energy required by the photovoltaic power generation device is separated out, and the remaining low-grade solar heat energy is fully utilized to heat the bypass flue to ensure the economy and operation safety of the coal-fired power generation device. BRIEF DESCRIPTION OF DRAWINGS

[0035] In order to more clearly illustrate the technical solutions of the embodiments of the application, the following will briefly introduce the drawings needed to be used in the embodiments of the application. The following drawings only show some embodiments of the application, and therefore should not be considered as a limitation to the scope. For those skilled in the art, other related drawings can also be obtained without creative labor on the basis of these drawings.

[0036] Figure 1 The structure schematic diagram of the power generation system provided by the embodiments of the application. DETAILED DESCRIPTION

[0037] In the prior art, the photoelectric conversion efficiency of the photovoltaic power generation device can reach more than 20%, but in actual application, the photovoltaic power generation device can only utilize visible light and near-infrared light with a wave band of 400-1100 nm in sunlight, and the remaining wave bands such as ultraviolet light and medium and far infrared light in sunlight are wasted, resulting in low utilization rate of solar energy.

[0038] With the implementation of the dual-carbon strategy, renewable energy sources such as wind and solar power have entered a stage of rapid development. However, these new energy sources are characterized by high volatility, requiring a significant proportion of flexible regulation resources in the power grid to absorb them. Utilizing existing coal-fired power generating units for peak shaving is an economical option.

[0039] With the implementation of the three-pronged reform, the peak-shaving capacity of coal-fired power generating units has been significantly enhanced. During the daytime when photovoltaic power generation equipment output is extremely high, coal-fired power generating units enter deep peak-shaving operation, resulting in a serious deviation from the design operating conditions and a sharp increase in coal consumption. As the main working mediums such as fuel, flue gas, and steam decrease with the load, the heat generated by coal-fired power generating units is insufficient under low-load conditions, affecting the execution of some of their auxiliary functions.

[0040] For example, coal-fired power generating units that employ bypass evaporation drying of high-salinity wastewater, already used in "zero-discharge" projects for high-salinity wastewater in several coal-fired power plants, rely on the high-temperature flue gas before the air preheater for heat source to atomize and evaporate the wastewater. This negatively impacts the thermal efficiency of the coal-fired power generating units. Under deep peak-shaving conditions, the heat generated by the coal-fired power generating units is insufficient, further affecting the evaporation and drying effect of the high-salinity wastewater.

[0041] To address the aforementioned technical problems, this application provides a power generation scheme for converting the solar energy carried by the remaining wavelengths of sunlight that cannot be utilized by photovoltaic power generation equipment into thermal energy, which is then used to heat the flue gas output from the bypass flue in a coal-fired power generation unit.

[0042] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0043] like Figure 1 As shown, Figure 1 This is a schematic diagram of the power generation system provided in an embodiment of this application. The power generation system includes a spectral frequency division device 100, a photovoltaic power generation device 200, a concentrating solar collector 300, and a coal-fired power generation unit 400.

[0044] The spectrum splitting device 100 is connected with the photovoltaic power generation device 200 and the light collection and heat collection device 300 respectively; the spectrum splitting device 100 is used for receiving solar energy and performing spectrum splitting processing on the received solar energy to obtain light waves of different wave bands, and the light waves of different wave bands are subsequently transmitted to different light wave utilization devices; in the embodiment of the application, the light wave utilization devices include the common photovoltaic power generation device 200 and the light collection and heat collection device 300 specially constructed in the embodiment of the application.

[0045] The photovoltaic power generation device 200 utilizes the light waves of the 400-1100 nm wave band, i.e. the light waves of the first wave band, and the light collection and heat collection device 300 utilizes the light waves of the remaining wave band, i.e. the light waves of the second wave band; in actual operation, when in a sunny day, i.e. in a period of sufficient solar energy, when the spectrum splitting device 100 receives sunlight and performs spectrum splitting processing on the sunlight, the light waves of the 400-1100 nm wave band obtained are transmitted to the photovoltaic power generation device 200, and the light waves of the remaining wave band are transmitted to the light collection and heat collection device 300.

[0046] The photovoltaic power generation device 200 is used as the main power generation force in the period of sufficient solar energy.

[0047] The coal-fired power generation unit 400 is used for entering a deep peak regulation working state when the photovoltaic power generation device 200 works, and entering a high-power working state when the photovoltaic power generation device 200 does not work.

[0048] The coal-fired power generation unit 400 includes a main path flue 410, an air preheater 420 and a bypass flue 430.

[0049] The main path flue 410 is used for transmitting flue gas discharged by the coal-fired power generation unit 400 to the outside of the coal-fired power generation unit 400; the air preheater 420 is arranged in the main path flue 410 and is used for preheating air to a certain temperature by the heat of the flue gas and then sending the air into the boiler of the coal-fired power generation unit 400, so as to reduce the flue gas temperature.

[0050] The bypass flue 430 is a pipeline drawn from the position of the main path flue 410 of the coal-fired power generation unit 400 located at the front side of the air preheater 420, and the bypass flue 430 can transmit the flue gas in the main path flue 410 out of the main path flue 410; in actual operation, the flue gas transmitted by the bypass flue 430 can be heated to obtain high-temperature flue gas, and the high-temperature flue gas is used for evaporating and drying the high-salt wastewater discharged by the coal-fired power generation unit 400.

[0051] The light collection and heat collection device 300 is also connected with the bypass flue 430, and the light collection and heat collection device 300 is used for converting the light energy carried by the light waves of the second wave band into heat energy, and heating the flue gas in the bypass flue 430 by using the heat energy to obtain high-temperature flue gas.

[0052] In actual operation, the light-gathering and heat-collecting device 300 is used to convert the light energy carried by the light waves of the second wave band into heat energy, which heats the flue gas in the bypass flue 430 to high-temperature flue gas; the high-temperature flue gas heats the flue gas in the main flue 410 above the bypass outlet of the air preheater 420, so that the temperature of the flue gas meets the low-load zero wastewater discharge requirement of the coal-fired power generating unit 400.

[0053] In an implementation manner, the light-gathering and heat-collecting device 300 comprises a light energy conversion device 310 and a heat-collecting device 320, the medium output end 311 of the light energy conversion device 310 is connected with the heat-collecting input end 321 of the heat-collecting device 320, and the heat-collecting output end 322 of the heat-collecting device 320 is connected with the first medium input end 312 of the light energy conversion device 310 to form a first circulation loop.

[0054] The light energy conversion device 310 is further connected with the light spectrum frequency division device 100, and is used to convert the light energy carried by the light waves of the second wave band into heat energy, and heat the heat exchange medium in the first circulation loop through the heat energy;

[0055] The heat-collecting device 320 can heat and treat the flue gas in the bypass flue 430 through the heated heat exchange medium to obtain high-temperature flue gas.

[0056] The heat-collecting device 320 can heat and treat the flue gas in the bypass flue 430 through the heated heat exchange medium to obtain high-temperature flue gas.

[0057] The light energy conversion device 310 can utilize the solar energy carried by the light waves of the second wave band; in actual operation, the light energy conversion device 310 performs light-gathering treatment on the light waves of the second wave band through a light-gathering mirror, heats the heat exchange medium in the first pipeline through the heat energy generated by the light-gathering treatment, and makes the heat exchange medium flow from the medium output end 311 to the heat-collecting input end 321 of the heat-collecting device 320; in the heat-collecting device 320, the heat-collecting device 320 heats the flue gas delivered by the bypass flue 410 through the heat energy carried by the heat exchange medium to obtain high-temperature flue gas; after the heat energy of the heat exchange medium is utilized by the heat-collecting device 320, the heat exchange medium flows out from the heat-collecting output end 322 of the heat-collecting device 320 and flows back to the light energy conversion device 310 through the first medium input end 312.

[0058] As Figure 1The direction indicated by the solid arrow in the figure is the circulation direction of the first circulation loop, i.e., "light energy conversion device 310 → medium output end 311 → heat collection input end 321 → heat collection device 320 → heat collection output end 322 → first medium input end 312 → light energy conversion device 310".

[0059] In actual operation, according to the energy matching principle, low-cost trough-type light concentration or Fresnel-type linear light concentrator can meet the light concentration requirement of the light energy conversion device 310, without the need for high-cost point light concentration; the heat collection device 320 can be a perforated plate type or a shell-and-tube type, which is not specifically limited in the present application.

[0060] In actual operation, the heat collection device 320 contains a large number of fins. In the deep peak regulation working condition, the bypass flue gas is heated by the heat exchange medium to obtain high-temperature flue gas, so that the high-temperature flue gas meets the heat demand of evaporating high-salinity wastewater.

[0061] In one implementation, the light-concentrating and heat-collecting equipment 300 further includes a first valve 330, which is arranged between the medium output end 311 and the heat collection input end 321; the first valve 330 is used to adjust whether the first circulation loop is conducted.

[0062] The first circulation loop does not always need to be in a circulating conducting state. When the solar energy is sufficient, i.e., the light energy conversion device 310 can utilize the second waveband light wave output by the spectrum splitting device 100, the first circulation loop needs to be in a conducting state, and therefore the first valve 330 is arranged to adjust the conducting state of the first circulation loop.

[0063] In actual operation, the opening and closing degree of the first circulation loop can also be adjusted by the first valve 330.

[0064] In one implementation, the light-concentrating and heat-collecting equipment 300 further includes a second valve 340, one end of which is connected to a position between the first valve 330 and the medium output end 311, and the other end is connected to the second medium input end 313 of the light energy conversion device 310, to form a second circulation loop.

[0065] The second valve 340 is used to adjust whether the second circulation loop is conducted.

[0066] The light energy conversion device 310 is further connected with a second pipeline, one end of the second pipeline is connected with the second medium input end 313 of the light energy conversion device 310, and the other end of the second pipeline is communicated with the pipeline between the medium output end 311 and the first valve 330 in the first pipeline, and the second pipeline and the pipeline between the position of the communication with the first circulation loop and the medium output end 311 in the first pipeline form a second circulation loop.

[0067] In the second circulation loop, the second valve 340 is arranged in the second pipeline, that is, one end of the second valve 340 is communicated with the position between the first valve 330 and the medium output end 311 through the second pipeline, and the other end of the second valve 340 is connected with the second medium input end 313 through the second pipeline.

[0068] The second circulation loop is a circulation loop without passing through the heat collecting device 320; in the embodiment of the present application, the purpose of arranging the first circulation loop is to transport the heat energy generated by the light energy conversion device 310 to the heat collecting device 320 through the heat exchange medium in the first circulation loop and to heat the flue gas in the bypass flue 410 into high-temperature flue gas, and therefore it is necessary to ensure that the temperature of the heat exchange medium in the first circulation loop is high enough, that is, the flue gas can be heated into high-temperature flue gas.

[0069] In actual operation, the temperature of the heat exchange medium is increased from normal temperature to a temperature at which the flue gas can be heated into high-temperature flue gas, and the heat exchange medium needs to be preheated, and when the heat exchange medium is preheated to a temperature at which the flue gas can be heated into high-temperature flue gas, the heat exchange medium can be flowed to the heat collecting device 320 through the first circulation loop; in the embodiment of the present application, in order to uniformly preheat the heat exchange medium in the first circulation loop, the second circulation loop is arranged for preheating the heat exchange medium.

[0070] In actual operation, the opening and closing degree of the second valve 340 in the second circulation loop can also be adjusted.

[0071] In one implementation manner, the light collecting and heat collecting equipment 300 further comprises a driving device 350, and the driving device 350 is arranged between the first valve 330 and the medium output end 311.

[0072] The driving device 350 is used to drive the heat exchange medium in the first circulation loop or the second circulation loop to flow in a preset flow direction.

[0073] The heat exchange medium in the first pipeline and the second pipeline needs to be driven by the driving device 350 to flow in the pipeline; in actual operation, the driving device 350 can be a circulating pump, which is used to maintain the circulating flow of the heat exchange medium in the first circulation loop or the second circulation loop.

[0074] In actual application, since the driving device 350 needs to drive the circulation flow of the heat exchange medium in the first and second circulation loops respectively in different time periods, the driving device 350 needs to be installed at the common pipeline of the two circulation loops, i.e. the driving device 350 is arranged between the first medium output end 311 and the "communication position of the second pipeline and the first pipeline" in the first pipeline, so that the driving device 350 is located in front of the first valve 330 and the second valve 340 in the preset flow direction.

[0075] In actual operation, the driving device 350 can also adjust the flow rate of the heat exchange medium in the circulation loop; the flow rate of the heat exchange medium is faster when the photovoltaic power generation device 200 outputs more, and the flow rate of the heat exchange medium is slower when the coal-fired power generating unit 400 processes more.

[0076] In actual application, the first valve 330 and the second valve 340 can be ball valves or butterfly valves, which are not limited in the present application.

[0077] In the embodiment of the present application, as shown in Figure 1 , the direction indicated by the solid arrow is the preset flow direction. Figure 1

[0078] In an implementation manner, the light condensation and heat collection device 300 further comprises a heat storage device 360; the heat storage device 360 is connected between the driving device 350 and the medium output end 311.

[0079] The heat storage device 360 is composed of a storage tank and is used to store the heat exchange medium. The heat storage device 360 is arranged at a position between the driving device 350 and the medium output end 311 in the first pipeline.

[0080] In the embodiment of the present application, the purpose of arranging the heat storage device 360 is to store the heat exchange medium by the storage tank arranged therein and to prevent the heat exchange medium in the first and second pipelines from damaging the first and second pipelines by using the stored heat exchange medium as a heat buffer zone.

[0081] In actual application, the heat storage device 360 can alleviate the influence of solar energy fluctuation on the light condensation and heat collection system; specifically, when the solar radiation is insufficient at the late evening, there is still part of the heat exchange medium stored in the heat storage device 360, and the heat energy carried by the heat exchange medium stored in the heat storage tank 4 can be used to continue heating the high-temperature flue gas.

[0082] In an implementation manner, when the power generation system is in a deep peak regulation working condition, the first valve 330 is opened to make the first circulation loop in a conducting state.

[0083] ​The spectral frequency device 100 performs spectral frequency processing on the sunlight to obtain light waves of a second wave band, and sends the light waves of the second wave band to the light energy conversion device 310.

[0084] The light energy conversion device 310 converts the light energy carried by the light waves of the second wave band into heat energy, and heats the heat exchange medium flowing in the first circulation loop, so that the temperature of the heat exchange medium in the first circulation loop is not lower than a first preset temperature.

[0085] The heat exchange medium carrying heat energy is delivered to the heat collecting device 320 through the first circulation loop, so that the heat collecting device 320 heats the flue gas delivered through the bypass flue 410 by using the heat energy carried by the heat exchange medium to obtain high-temperature flue gas.

[0086] In actual operation, the temperature of the high-temperature flue gas obtained by the heat collecting device 320 can be controlled by controlling the flow of the heat exchange medium, and the temperature of the high-temperature flue gas needs to be maintained above 300°C.

[0087] In an implementation, before the power generation system enters the deep peak regulation working condition, the first valve 330 is closed, so that the first circulation loop is in an open circuit state, and the second valve 340 is opened, so that the second circulation loop is in a conduction state.

[0088] The spectral frequency device 100 performs spectral frequency processing on the sunlight to obtain light waves of a second wave band, and sends the light waves of the second wave band to the light energy conversion device 310.

[0089] The light energy conversion device 310 converts the light energy carried by the light waves of the second wave band into heat energy, and preheats the heat exchange medium flowing in the second circulation loop until the heat exchange medium reaches a second preset temperature.

[0090] In an implementation, the coal-fired power generating unit further comprises a main flue 410 and an air preheater 420, and the air preheater 420 is arranged in the main flue 410.

[0091] The air preheater 420 is used to preheat air to a third preset temperature by the heat of the flue gas delivered through the main flue 410, and then send the air into the coal-fired power generating unit 400 to reduce the temperature of the flue gas.

[0092] In actual operation, the high-temperature flue gas is obtained by the heat energy indirectly provided by the light waves of the second wave band in the sunlight, which can reduce the loss of high-quality flue gas and reduce the low-temperature corrosion of the air preheater 420.

[0093] In an implementation manner, the coal-fired power generating unit 400 further comprises a soot blowing device 440, which is also arranged in the main flue 410; the soot blowing device 440 is used for soot blowing treatment on the heat receiving surface related to the flue gas respectively transported by the main flue 410 or the bypass flue 430.

[0094] The soot blowing device 440 is arranged for soot blowing; the soot of the flue heat receiving surface of the coal-fired power generating unit 400 is a common phenomenon, especially at the horizontal flue, the tail flue and other parts, due to the factors such as the slow flue gas flow and the gravity, the dust is easy to deposit. If not removed in time, the accumulated dust will cause the heat transfer efficiency of the heat receiving surface to decrease, the flue gas temperature of the boiler to rise, and even cause the heat receiving surface to overheat, coking, ash collapse and other accidents, which seriously affect the operation reliability and economy of the boiler.

[0095] As can be seen from the above, the power generation system provided by the embodiment of the present application, the high power of the photovoltaic power generation device 200 is accompanied by the deep peak regulation of the coal-fired power generating unit 400, at this time, the remaining solar heat energy is matched with the current situation that the coal-fired power generating unit 400 needs a large amount of heat to dry the low-load high-salt wastewater. At low load, the heat energy indirectly generated by the second wave band of light waves heats the flue gas to obtain high-temperature flue gas, effectively realizing zero discharge of wastewater; in addition, the required solar heat energy heating temperature is about 300 degrees Celsius, which is matched with the line condenser, realizing the temperature matching utilization.

[0096] In addition, the embodiment of the present application does not hinder the normal operation of the original photovoltaic power generation device 200 and the coal-fired power generating unit 400, and utilizes the characteristics that the high load working interval of the photovoltaic power generation device 200 corresponds to the low load interval of the coal-fired power generating unit 400 to increase the safety of the high-salt wastewater removal operation of the coal-fired power generating unit 400, so that the high-grade light energy required by the photovoltaic power generation device 200 is separated out, and the remaining low-grade solar heat energy is fully utilized to heat the bypass flue to ensure the economy and operation safety of the coal-fired power generating unit 400.

[0097] In the embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other manners. The above-described device embodiments are only schematic; for example, the division of the units is only a logical function division, and there can be another division manner in actual implementation; for example, a plurality of units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the displayed or discussed mutual couplings or direct couplings or communication connections between different units, components or the like can be indirect couplings or communication connections through some interfaces, devices or units, and can be electrical, mechanical or other forms.

[0098] In addition, the units described as separate components may or may not be physically separate, and the components displayed as units may or may not be physical units, i.e. may be located in one place, or may be distributed to multiple network units. Part or all of the units can be selected according to actual needs to achieve the purpose of the embodiment scheme.

[0099] Furthermore, the functional modules in each embodiment of the present application can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part.

[0100] It should be noted that if the function is realized in the form of a software function module and sold or used as an independent product, it can be stored in a computer readable storage medium. Based on this understanding, the technical solutions of the present application essentially or the part that contributes to the prior art or part of the technical solutions can be embodied in the form of a software product. The computer software product is stored in a storage medium, including a number of instructions to make a computer device (which can be a personal computer, a server, or a network device, etc.) execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (Read-Only Memory, ROM), random access memory (Random Access Memory, RAM), magnetic disk or optical disk, and various program code storage media.

[0101] In this paper, such as first and second relationship terms are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between the entities or operations.

[0102] The above is only an embodiment of the present application and does not limit the protection scope of the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A power generation system, characterized by, The power generation system includes a spectral frequency division device, a photovoltaic power generation device, a concentrating solar thermal collection device, and a coal-fired power generation unit; The spectral frequency division device is connected to the photovoltaic power generation device and the concentrating solar thermal collector device respectively; The spectral frequency division device is used to perform spectral frequency division processing on sunlight to obtain light waves in the first band and the second band, and to transmit the light waves in the first band to the photovoltaic power generation device and the light waves in the second band to the concentrating solar collector device. The coal-fired power generation unit includes a bypass flue, and the concentrating solar collector is also connected to the bypass flue. The concentrating solar collector is used to convert the light energy carried by the second band of light waves into heat energy, and to use the heat energy to heat the flue gas in the bypass flue to provide heat energy for the treatment of high-salt wastewater.

2. The power generation system of claim 1, wherein, The concentrating solar thermal collector includes a solar energy conversion device and a solar collector. The medium output end of the solar energy conversion device is connected to the solar collector input end of the solar collector, and the solar collector output end of the solar collector is connected to the first medium input end of the solar energy conversion device to form a first circulation loop. The light energy conversion device is also connected to the spectral frequency division device, and is used to convert the light energy carried by the light wave in the second band into heat energy, and to heat the heat exchange medium in the first circulation loop through the heat energy. The heat collection device can heat the flue gas in the bypass flue through the heated heat exchange medium to obtain high-temperature flue gas.

3. The power generation system of claim 2, wherein, The concentrating solar collector also includes a first valve, which is disposed between the medium output end and the solar collector input end; the first valve is used to adjust whether the first circulation loop is open.

4. The power generation system of claim 3, wherein, The concentrating solar collector also includes a second valve, one end of which is connected to the position between the first valve and the medium output end, and the other end is connected to the second medium input end of the solar energy conversion device to form a second circulation loop; The second valve is used to regulate whether the second circulation loop is open.

5. The power generation system of claim 4, wherein, The concentrating solar collector also includes a driving device, which is disposed between the first valve and the medium output end; The driving device is used to drive the heat exchange medium in the first circulation loop or the second circulation loop to flow in a preset flow direction.

6. The system of claim 5, wherein, The concentrating solar collector also includes a thermal storage device; the thermal storage device is connected between the driving device and the medium output end. The heat storage device consists of a storage tank for storing the heat exchange medium.

7. The system according to any one of claims 3 to 6, characterized in that, When the power generation system is in deep peak shaving mode, the first valve opens, making the first circulation loop in a conductive state; The spectral frequency division device performs spectral frequency division processing on sunlight to obtain a second band of light waves, and sends the second band of light waves to the light energy conversion device; The light energy conversion device converts the light energy carried by the second band of light waves into heat energy and heats the heat exchange medium flowing in the first circulation loop, so that the temperature of the heat exchange medium in the first circulation loop is not lower than the first preset temperature. The heat transfer medium carrying the heat energy is delivered to a heat collecting device through the first circulation loop, and the heat collecting device heats the flue gas delivered through the bypass flue by using the heat energy carried by the heat transfer medium to obtain high-temperature flue gas.

8. The system of any one of claims 4 to 6, wherein, Before the power generation system enters the deep peak regulation working condition, the first valve is closed to make the first circulation loop in an open circuit state, and the second valve is opened to make the second circulation loop in a conducting state, within a preset time period; The spectral frequency device performs spectral frequency processing on sunlight to obtain light waves of a second wave band, and sends the light waves of the second wave band to the light energy conversion device; The light energy conversion device converts light energy carried by the light waves of the second wave band into heat energy and preheats the heat transfer medium flowing in the second circulation loop until the heat transfer medium reaches a second preset temperature.

9. The system of claim 7, wherein, The coal-fired power generation unit further comprises a main flue and an air preheater, and the air preheater is arranged in the main flue. The air preheater is used to preheat air to a third preset temperature by using the heat of the flue gas delivered through the main flue, and then the air is sent into the coal-fired power generation unit to reduce the temperature of the flue gas.

10. The system of claim 9, wherein, The coal-fired power generation unit further comprises a soot blowing device, and the soot blowing device is also arranged in the main flue. The soot blowing device is used to perform soot blowing treatment on the heated surfaces respectively delivered by the main flue or the bypass flue.

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