Large-temperature-difference waste heat driven multi-mode flexible conversion cooling heating and power integrated system

Abstract

The invention provides a multi-mode flexible conversion cooling, heating and power integrated system driven by large-temperature-difference waste heat, and belongs to the technical field of energy environmental protection. The system comprises an organic Rankine power generation unit (comprising a high-pressure circulation loop and a low-pressure circulation loop), a refrigeration unit and a heat supply unit (comprising two heat supply branches), the system can be flexibly switched among a heat mode, an electricity mode, an electric cooling mode, an electric heating mode and an electric cooling and heating mode according to the temperature characteristics of a heat source by adjusting a three-way valve, and the ratio of cooling, heating and electricity is adjusted and controlled; the high-low pressure two-stage circulation structure promotes gradient utilization of energy; an ejector is additionally arranged in the high-pressure loop to improve heat source recovery and system power capability; an ejector is adopted in the refrigerating circuit to reduce power consumption and simplify the structure; a cold source side and a low-temperature heat source are reused to improve the overall energy efficiency; the system is suitable for large-temperature-difference waste heat resources, meets the multi-mode switching requirement and is suitable for diversified energy use scenes in different areas and seasons.

Description

Technical Field

[0001] The present invention belongs to the technical field of energy and environmental protection, and specifically relates to a large temperature difference waste heat driven multi-mode flexible conversion cooling, heating and electricity integrated system. Background Art

[0002] With the development of social economy, my country's demand for energy has increased dramatically, and the energy crisis has become increasingly serious. However, in the industrial production process, up to 50% of the total heat is directly discharged into the environment and becomes waste heat. Recycling waste heat resources can not only effectively improve the comprehensive utilization rate of energy and alleviate the energy crisis, but also reduce the pollution caused by emissions to the environment, which helps to achieve sustainable social development.

[0003] The integrated cooling, heating and power system is an energy conversion system that recovers waste heat resources, uses heat energy to generate electricity, and provides heating and cooling to users. The tri-integrated system can meet multiple energy needs and improve the energy efficiency of the entire system, so it has received widespread attention. Although the integrated cooling, heating and power system has many advantages such as efficient complementarity, safety and controllability, and environmental improvement, the following key issues need to be solved when the integrated cooling, heating and power system is applied to waste heat recovery with large temperature differences:

[0004] First: Strengthen the matching of heat sources and realize the cascade utilization of waste heat. Conventional recovery of waste heat resources with large temperature differences is mainly based on a single thermal cycle structure. The exhaust temperature after recovery is still high, and the waste heat recovery is insufficient. At the same time, the large heat exchange temperature difference makes the temperature matching of the heat exchange process not strong, resulting in The loss increases and the system's ability to do work decreases.

[0005] Second: Strengthen the reuse of heat discharged from the cold source side to improve the overall energy utilization efficiency. In the traditional cold, heat and power integrated system, the heat discharged from the cold source side is not effectively utilized, and the condensation waste heat is directly discharged into the environment, resulting in a further waste of energy and affecting the energy utilization efficiency of the system.

[0006] Third: Strengthen the coordination of the system's thermal performance and economic performance. In order to improve the system's thermal performance and ensure that the system has sufficient heat source intake, the existing technology often increases its output power at the expense of increased economic costs due to configuration changes, resulting in poor economic performance of the system, and the actual application and promotion of the system are subject to certain restrictions.

[0007] Fourth: Strengthen the flexibility and controllability of the system's switching of multiple co-production modes. The system can flexibly switch between multiple operating modes (heat, electricity, electric cooling, electric heating, and electric cooling and heating) according to different regions and seasons and based on user needs, and can further actively adjust the working fluid flow ratio to achieve the regulation of power, cooling and heat, thereby improving the scope of application and control flexibility of the integrated system.

[0008] In the prior art, there is a combined heat and power system using CO2 as the working fluid. This technology can realize switching between thermal power mode, cooling mode and heat and power mode; however, the system configuration is relatively simple, the temperature range of recoverable waste heat resources is limited, and the cycle adaptability is not strong; the heat on the cold source side is not recycled, and there are problems such as low overall energy utilization of the system.

[0009] Another technology is a combined cooling, heating and power system based on ammonia solution, which can also realize the switching of the working circuit between three modes. However, this technology is mainly for single-stage waste heat recovery. In the case of large temperature difference of heat source, there is a large temperature difference in the heat exchange process. The system has the limitations of increased power loss and insufficient utilization of waste heat; the relatively complex configuration of the system leads to increased economic costs, and there are no corresponding improvement measures in terms of system efficiency and economic coordination. Summary of the invention

[0010] The purpose of the present invention is to provide a large temperature difference waste heat driven multi-mode flexible conversion cooling, heating and electricity integrated system, aiming to solve the problems in the prior art.

[0011] To achieve the above-mentioned object, the present invention provides the following technical solutions: a large temperature difference waste heat driven multi-mode flexible conversion cooling, heating and electricity integrated system, comprising a machine Rankine power generation unit, a refrigeration unit and a heating unit;

[0012] The organic Rankine power generation unit comprises a high-pressure circulation loop and a low-pressure circulation loop;

[0013] The heating unit comprises a heating branch I and a heating branch II;

[0014] The heating branch I is connected in parallel with the high-pressure circulation loop of the organic Rankine power generation unit. The organic Rankine power generation unit adopts a high-low pressure two-stage circulation configuration, and an ejector a is arranged in the high-pressure circulation loop. The ejector b is used in the refrigeration unit instead of the compressor. At the same time, the heat discharged from the cold source side and the heat source after heat exchange are reused, thereby improving the overall energy utilization efficiency of the system and reducing the economic cost of the system.

[0015] Preferably, the high-pressure circulation loop includes a high-pressure working fluid pump, a high-pressure preheater, a high-pressure evaporator, a high-pressure superheater, a high-pressure turbine, and a high-pressure generator;

[0016] The low-pressure circulation loop includes a low-pressure working fluid pump, a low-pressure steam generator, a gas-liquid separator, a low-pressure turbine, and a low-pressure generator.

[0017] In the preferred embodiment of the present invention, the refrigeration unit includes an ejector b, a refrigeration evaporator, a throttle valve, and a cold user side.

[0018] Preferably, in this solution, the heating branch I includes a heat exchanger a and a heat user side a;

[0019] The heating branch II includes a heat exchanger b and a heat user side b.

[0020] In this solution, the outlet of the high-pressure working fluid pump is connected to the inlet of the high-pressure preheater, the outlet of the high-pressure preheater is connected to the inlet of the high-pressure evaporator, the outlet of the high-pressure evaporator is connected to the right inlet of the ejector a, and the bottom inlet of the ejector a is connected to the bottom outlet of the gas-liquid separator of the low-pressure circulation loop through the first outlet of the three-way valve b;

[0021] The ejector a outlet is connected to the low temperature side inlet of the high pressure superheater, the low temperature side outlet of the high pressure superheater is connected to the high pressure turbine inlet, and the high pressure turbine is connected to the high pressure generator through a coupling.

[0022] Preferably, the outlet of the low-pressure working fluid pump is connected to the low-temperature side inlet of the low-pressure steam generator;

[0023] The outlet of the low-pressure steam generator is connected to the inlet of the gas-liquid separator, the top outlet of the gas-liquid separator is connected to the inlet of the low-pressure turbine, and the low-pressure turbine is connected to the low-pressure generator through a coupling.

[0024] In this embodiment, the outlet of the throttle valve is connected to the low-temperature side inlet of the refrigeration evaporator, the low-temperature side outlet of the refrigeration evaporator is connected to the bottom inlet of the ejector b, and the left inlet of the ejector b is connected to the bottom outlet of the gas-liquid separator of the low-pressure circulation loop through the second outlet of the three-way valve b.

[0025] In the preferred embodiment of the present invention, the outlet of the high-pressure turbine is connected to a mixer and is connected to its right inlet, the top inlet of the mixer is connected to the outlet of the low-pressure turbine, and the left inlet of the mixer is connected to the outlet of the ejector b.

[0026] Preferably, the outlet of the mixer is connected to a condenser and is connected to its high-temperature side inlet, the high-temperature side outlet of the condenser is provided with a three-way valve c and is connected to its inlet, the first outlet of the three-way valve c is divided into two branches, one branch is connected to the inlet of a low-pressure working fluid pump, and the other branch is connected to the inlet of a throttle valve of a refrigeration unit.

[0027] The preferred embodiment of this scheme is that the system flexibly switches between multiple modes of heat, electricity, electric cooling, electric heating and electric cooling and heating according to the different waste heat inlet temperatures, and realizes the proportional relationship of work and heat output by adjusting the working fluid flow ratio through the valve. The cold side outlet of the condenser is connected to the inlet of the three-way valve d, the first outlet of the three-way valve d is connected to the cold side inlet of the heat exchanger b, and the cold side outlet of the heat exchanger b is connected to the low-temperature hot water outlet.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] 1. This large temperature difference waste heat driven multi-mode flexible conversion cold, heat and power integrated system adopts a high and low pressure two-stage circulation configuration in view of the large temperature difference range of waste heat resources. The heat source and the system undergo heat exchange twice to reduce the heat exchange temperature difference and reduce the system It can reduce the loss, be beneficial to the cascade utilization of energy, and help to improve the efficiency of waste heat recovery.

[0030] 2. This large temperature difference waste heat driven multi-mode flexible conversion cold, heat and electricity integrated system, in the high-pressure circulation loop, adds an ejector between the superheater and the evaporator. The ejection effect of high-temperature and high-pressure fluid is conducive to increasing the recovery of heat sources more fully, and also to increasing the flow of superheated steam to improve the system's work capacity. In the refrigeration circuit, the ejector is used instead of the compressor, and the entire refrigeration cycle is driven by thermal energy, which can reduce the system's power consumption, simplify the system structure, and reduce the system's economic cost.

[0031] 3. This large temperature difference waste heat driven multi-mode flexible conversion cold, heat and electricity integrated system uses the heat discharged from the condenser in the system's power circuit and refrigeration circuit, and the low-temperature heat source after heat release to heat the cold source fluid, and increase the cold source outlet temperature as much as possible to meet the domestic hot water or heating needs of heat users. The reuse of the cold source side and the low-temperature heat source can further improve the overall system energy utilization efficiency of the system and obtain certain thermal economic benefits.

[0032] 4. This large temperature difference waste heat driven multi-mode flexible conversion cooling, heating and electricity integrated system can use waste heat to prepare domestic hot water in the low temperature range (below 65°) to meet the thermal energy needs of users; in the relatively high temperature range (above 65°), on the premise of ensuring that the system converts low-grade waste heat energy into high-grade electricity, it can further provide cooling and / or heating to users. The system can switch between five modes: heat, electricity, electric cooling, electric heating, and electric cooling and heating, which broadens the conventional energy consumption mode and expands the scope of waste heat resource temperature recovery, and can meet the various energy needs of users in different regions and seasons. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0034] Figure 1 A schematic diagram of a large temperature difference waste heat driven multi-mode flexible conversion cooling, heating and electricity integrated system of the present invention;

[0035] Figure 2 A schematic diagram of the thermal mode of a large temperature difference waste heat driven multi-mode flexible conversion cold, heat and electricity integrated system in the present invention;

[0036] Figure 3 It is a schematic diagram of the electrical mode of a large temperature difference waste heat driven multi-mode flexible conversion cooling, heating and electricity integrated system in the present invention;

[0037] Figure 4 A schematic diagram of an electric cooling mode of a large temperature difference waste heat driven multi-mode flexible conversion cooling, heating and electricity integrated system in the present invention;

[0038] Figure 5 A schematic diagram of the electric and thermal mode of a large temperature difference waste heat driven multi-mode flexible conversion cooling, heating and electricity integrated system in the present invention;

[0039] Figure 6 Schematic diagram of the electric heating and cooling modes of a large temperature difference waste heat driven multi-mode flexible conversion cooling, heating and electricity integrated system in the present invention.

[0040] In the figure: 1-three-way valve a, 2-heat exchanger a, 3-hot user side a, 4-high-pressure superheater, 5-high-pressure evaporator, 6-high-pressure preheater, 7-ejector a, 8-high-pressure turbine, 9-high-pressure generator, 10-high-pressure working fluid pump, 11-low-pressure steam generator, 12-gas-liquid separator, 13-three-way valve b, 14-low-pressure turbine, 15-low-pressure generator, 16-mixer, 17-condenser, 18-low-pressure working fluid pump, 19-three-way valve c, 20-three-way valve d, 21-ejector b, 22-refrigeration evaporator, 23-throttle valve, 24-cold user side, 25-three-way valve e, 26-heat exchanger b, 27-hot user side b. DETAILED DESCRIPTION

[0041] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0042] Example

[0043] See also Figure 1-Figure 6 The present invention provides the following technical solutions: A large temperature difference waste heat driven multi-mode flexible conversion cold, heat and electricity integrated system includes an organic Rankine power generation unit, a refrigeration unit and a heating unit. The organic Rankine power generation unit includes a high-pressure circulation loop and a low-pressure circulation loop. The setting of the high-low pressure two-stage circulation loop of the system power generation unit can enhance the matching of the heat source and realize the cascade utilization of waste heat. The heating unit includes a heating branch I and a heating branch II.

[0044] In this embodiment: the connection relationship of the specific components of each unit of the present invention is as follows: in the high-pressure circulation loop of the power generation unit, the outlet of the high-pressure working fluid pump 10 is connected to the inlet of the high-pressure preheater 6, the outlet of the high-pressure preheater 6 is connected to the inlet of the high-pressure evaporator 5, the right inlet of the ejector a7 is connected to the outlet of the high-pressure evaporator 5, the bottom inlet of the ejector a7 is connected to the bottom outlet of the gas-liquid separator 12 of the low-pressure circulation loop through the first outlet of the three-way valve b13, the outlet of the ejector a7 is connected to the inlet of the low-temperature side of the high-pressure superheater 4, the outlet of the low-temperature side of the high-pressure superheater 4 is connected to the inlet of the high-pressure turbine 8, and the high-pressure turbine 8 and the high-pressure generator 9 are connected via a coupling.

[0045] In this embodiment: the power generation unit has a low-pressure circulation loop, the outlet of the low-pressure working fluid pump 18 is connected to the low-temperature side inlet of the low-pressure steam generator 11, the outlet of the low-pressure steam generator 11 is connected to the inlet of the gas-liquid separator 12, the top outlet of the gas-liquid separator 12 is connected to the inlet of the low-pressure turbine 14, and the low-pressure turbine 14 is connected to the low-pressure generator 15 through a coupling.

[0046] In this embodiment: in the refrigeration unit, the outlet of the throttle valve 23 is connected to the inlet on the low-temperature side of the refrigeration evaporator 22, the outlet on the low-temperature side of the refrigeration evaporator 22 is connected to the bottom inlet of the ejector b21, and the left inlet of the ejector b21 is connected to the bottom outlet of the gas-liquid separator 12 of the low-pressure circulation loop through the second outlet of the three-way valve b13.

[0047] In this embodiment: the right side inlet of the mixer 16 is connected to the outlet of the high-pressure turbine 8, the top inlet of the mixer 16 is connected to the outlet of the low-pressure turbine 14, the left side inlet of the mixer 16 is connected to the outlet of the ejector b21, the outlet of the mixer 16 is connected to the high-temperature side inlet of the condenser 17, the high-temperature side outlet of the condenser 17 is connected to the inlet of the three-way valve c19, the first outlet of the three-way valve c19 is divided into two branches, one branch is connected to the inlet of the low-pressure working fluid pump 18, and the other branch is connected to the inlet of the high-pressure working fluid pump 10, and the second outlet of the three-way valve c19 is connected to the inlet of the throttle valve 23.

[0048] In this embodiment: the system has multiple modes including heat mode, electric mode, electric cooling mode, electric heating mode and electric heating and cooling mode. The switching between the various modes of the system is achieved by adjusting the three-way valve a1, the three-way valve b13, the three-way valve c19, the three-way valve d20 and the three-way valve e25.

[0049] In this embodiment: in the system heat mode, when the waste heat inlet temperature is lower than 65°C, the waste heat is not enough to generate electricity and is only used directly for heating. In the system heat mode, the second outlet of the three-way valve a1 is closed. Specifically, Figure 2As shown in the figure (black line indicates connection, gray line indicates disconnection), after the heat source enters from the three-way valve a1, it is discharged from the first outlet of the three-way valve a1 into the high-temperature side of the heat exchanger a2, releases heat and cools down, and then enters the waste heat outlet a from the high-temperature side outlet of the heat exchanger a2 and is discharged. After the cold water enters the heat exchanger a2 and absorbs the heat from the heat source to heat up, it supplies high-temperature hot water to the heat user side a3. By adjusting the opening of the three-way valve a1, the heat source flow rate flowing into the heat exchanger a2 can be controlled, thereby adjusting the output heat.

[0050] In this embodiment: in the system power mode, when the waste heat inlet temperature is higher than 65°C, the waste heat can be used to convert into high-quality electrical energy. In the system power mode, close the first outlet of the three-way valve a1, the second outlet of the three-way valve b13, the second outlet of the three-way valve c19, the first outlet of the three-way valve d20, and the first outlet of the three-way valve e25. Figure 3As shown (the black route indicates connection, and the gray route indicates disconnection), the waste heat passes through the three-way valve a1 and enters the high-pressure superheater 4 of the high-pressure circulation loop from its second outlet to release heat, then enters the high-pressure evaporator 5, and then enters the high-pressure preheater 6. The cooled heat source is discharged from the outlet of the high-pressure preheater 6 and enters the low-pressure steam generator 11 of the low-pressure circulation loop to further release heat, and then enters the three-way valve e25, passes through the second outlet of the three-way valve e25, and is discharged from the waste heat outlet b. In the high-pressure circulation loop of the organic Rankine power generation unit, the organic working fluid enters from the low-temperature side of the high-pressure preheater 6 after being pressurized in the high-pressure working fluid pump 10, and enters the high-pressure evaporator 5 after being preheated. The working fluid further absorbs heat in the high-pressure evaporator 5 and is converted into high-temperature and high-pressure steam, and then enters from the right inlet of the ejector a7 as a working fluid. Part of the low-pressure liquid organic working fluid discharged from the bottom of the gas-liquid separator 13 passes through the first outlet of the three-way valve b13 and enters from the bottom inlet of the ejector a7 as an ejection fluid. The two fluids are mixed in the ejector a7, and the ejection effect of the formed high-temperature and high-pressure fluid can enhance the utilization of the heat source more fully, and is also conducive to increasing the flow rate of superheated steam. The steam discharged from the outlet of the ejector a7 enters the high-pressure superheater 4 for reheating, and the superheated organic steam enters the high-pressure turbine 8 to expand and do work, driving the high-pressure generator 9 to output electrical energy. In the low-pressure circulation loop of the organic Rankine power generation unit, the low-pressure liquid organic working fluid is pressurized in the working fluid pump 18 and discharged from its outlet, enters the low-pressure steam generator 11 to absorb heat and then converts into a two-phase working fluid, and then enters the gas-liquid separator 12. The saturated steam is discharged from the top of the gas-liquid separator 12 and enters the low-pressure turbine 14 to expand and do work. The low-pressure turbine 14 drives the low-pressure generator 15 through the coupling to output electrical energy. The exhaust steam at the outlet of the high-pressure turbine 8 of the high-pressure circulation loop of the power generation unit and the exhaust steam at the outlet of the low-pressure turbine 14 of the low-pressure circulation loop enter the mixer 16 for mixing, and then enter the condenser 17 to cool into a liquid working fluid. After the liquid working fluid passes through the three-way valve c19, it enters the low-pressure working fluid pump 18 of the low-pressure circulation loop and the high-pressure working fluid pump 10 of the high-pressure circulation loop from the first outlet of the three-way valve c19, and thus completes a cycle. The high-low pressure two-stage circulation configuration of the system can reduce the heat exchange temperature difference of the system and is conducive to the cascade utilization of energy.

[0051] In this embodiment: the system is in electric cooling mode. When the waste heat inlet temperature is higher than 65°C, the system can meet both electricity and cooling requirements. When the system is in electric cooling mode, close the first outlet of the three-way valve a1, the first outlet of the three-way valve d20 and the first outlet of the three-way valve e25, and open the first and second outlets of the three-way valve b13 and the first and second outlets of the three-way valve c19. Figure 4As shown (the black route indicates connection, and the gray route indicates disconnection), the path of the waste heat is the same as the path of the waste heat in the system electrical mode, and the high and low pressure circulation loops of the power generation unit are the same as the high and low pressure circulation loops in the system electrical mode. In the refrigeration unit, the liquid organic working fluid is expanded and decompressed in the throttle valve 23 and then discharged from its outlet, and then enters from the low temperature side of the refrigeration evaporator 22, absorbs the heat of the air in the refrigeration evaporator 22, and is converted into low-pressure saturated working fluid vapor and discharged from its low temperature side outlet, and then enters the ejector b21 as an induced fluid, and another part of the liquid organic working fluid discharged from the bottom of the gas-liquid separator 12 passes through the second outlet of the three-way valve b13 and enters the left inlet of the ejector b21 as a working fluid, and the two fluids are mixed in the ejector b21 and then discharged from it. The high-temperature air is discharged from the outlet of the high-pressure turbine 8 of the high-pressure circulation loop of the power generation unit and the low-pressure turbine 14 outlet exhaust steam of the low-pressure circulation loop in the mixer 16, and then enters the condenser 17 to be cooled into a liquid working medium. After the liquid working medium passes through the three-way valve c19, it enters the low-pressure working medium pump 18 of the low-pressure circulation loop and the high-pressure working medium pump 10 of the high-pressure circulation loop from the first outlet of the three-way valve c19, and enters the throttle valve 23 of the refrigeration unit from the second outlet of the three-way valve c19, thus completing a cycle. In the refrigeration unit, the high-temperature air enters the high-temperature side of the refrigeration evaporator 22, and after releasing heat in the refrigeration evaporator 22, it is discharged from the high-temperature side outlet of the refrigeration evaporator 22 and enters the cold user side to meet the cold energy demand. By adjusting the opening of the three-way valve b13 and the three-way valve c19, the flow rate of the liquid working medium flowing into the ejector b21 and the throttle valve 23 can be controlled, thereby adjusting the output quantity of electric energy and cold energy.

[0052] In this embodiment: in the system electric heating mode, when the waste heat inlet temperature is higher than 65°C, the system can meet both electricity and heat requirements. In the system electric heating mode, close the first outlet of the three-way valve a1, the second outlet of the three-way valve b13, the second outlet of the three-way valve c19, the second outlet of the three-way valve d20 and the second outlet of the three-way valve e25. Figure 5As shown (black line indicates connection, gray line indicates disconnection), the waste heat passes through the second outlet of the three-way valve a1 and enters the high-pressure superheater 4 of the high-pressure circulation loop to release heat, then enters the high-pressure evaporator 5 and the high-pressure preheater 6 in sequence, and enters the low-pressure steam generator 11 of the low-pressure circulation loop after being discharged from the outlet of the high-pressure preheater 6 to further release heat, then enters the three-way valve e25, passes through the first outlet of the three-way valve e25, and is discharged from the waste heat outlet c. The high and low pressure circulation loops of the power generation unit are the same as those in the system power mode. In the heating branch II, the cold water absorbs heat and heats up in the condenser 17, then enters the three-way valve d20 and is discharged from its first outlet, then enters the heat exchanger b26 and absorbs heat and heats up again, and then supplies high-temperature hot water to the heat user side b27. By adjusting the opening of the three-way valve d20 and the three-way valve e25, the cooling water flow and waste heat energy flowing into the heat exchanger 26 can be controlled, thereby adjusting the amount of heat energy output.

[0053] In this embodiment: the system is in electric cooling and heating mode. When the waste heat inlet temperature is higher than 65°C, the system can meet the electricity, cooling and heating requirements at the same time. When the system is in electric cooling and heating mode, close the first outlet of the three-way valve a1, the second outlet of the three-way valve d20 and the second outlet of the three-way valve e25, and open the first and second outlets of the three-way valve b13 and the first and second outlets of the three-way valve c19. Specifically, Figure 6 As shown (black route indicates connection), the waste heat passes through the second outlet of the three-way valve a and enters the high-pressure superheater 4 of the high-pressure circulation loop to release heat, then enters the high-pressure evaporator 5, and then enters the high-pressure preheater 6. After being discharged from the outlet of the high-pressure preheater 6, it enters the low-pressure steam generator 11 of the low-pressure circulation loop to further release heat, and then enters the three-way valve e25, passes through the first outlet of the three-way valve e25, and is discharged from the waste heat outlet c. The high and low pressure circulation loops of the power generation unit are the same as those of the system in the electric mode, the refrigeration loop is the same as the refrigeration loop in the system in the electric cooling mode, and the heating branch II is the same as the heating branch II in the system in the electric heating mode. By adjusting the opening of the three-way valve b13, the flow rate of the working fluid flowing into the ejector b21 can be controlled. By adjusting the opening of the three-way valve c19, the flow rate of the working fluid flowing into the throttle valve 23 can be controlled. By adjusting the three-way valve d20, the flow rate of cooling water flowing into the heat exchanger 26 can be controlled. By adjusting the opening of the three-way valve e25, the waste heat energy flowing into the heat exchanger 26 can be controlled, thereby achieving the goal of adjusting the output amount of electrical energy, cold energy and thermal energy.

[0054] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A large temperature difference waste heat driven multi-mode flexible conversion cooling, heating and power integrated system, characterized in that: It includes an organic Rankine power generation unit, a cooling unit and a heating unit; The organic Rankine power generation unit comprises a high-pressure circulation loop and a low-pressure circulation loop; The heating unit comprises a heating branch I and a heating branch II; The heating branch I is connected in parallel with the high-pressure circulation loop of the organic Rankine power generation unit. The organic Rankine power generation unit adopts a high-low pressure two-stage circulation configuration, and an ejector a (7) is arranged in the high-pressure circulation loop. The ejector b (21) is used in the refrigeration unit instead of the compressor. At the same time, the heat discharged from the cold source side and the heat source after heat exchange are reused, thereby improving the overall energy utilization efficiency of the system and reducing the economic cost of the system.

2. According to claim 1, a large temperature difference waste heat driven multi-mode flexible conversion cooling, heating and power integrated system, characterized in that: The high-pressure circulation loop comprises a high-pressure working fluid pump (10), a high-pressure preheater (6), a high-pressure evaporator (5), a high-pressure superheater (4), a high-pressure turbine (8), and a high-pressure generator (9); The low-pressure circulation loop comprises a low-pressure working fluid pump (18), a low-pressure steam generator (11), a gas-liquid separator (12), a low-pressure turbine (14), and a low-pressure generator (15).

3. According to claim 2, a large temperature difference waste heat driven multi-mode flexible conversion cooling, heating and power integrated system is characterized by: The refrigeration unit comprises an ejector b (21), a refrigeration evaporator (22), a throttle valve (23), and a cold user side (24).

4. According to claim 3, a large temperature difference waste heat driven multi-mode flexible conversion cooling, heating and power integrated system is characterized by: The heating branch I comprises a heat exchanger a (2) and a heat user side a (3); The heating branch II includes a heat exchanger b (26) and a heat user side b (27).

5. According to claim 4, a large temperature difference waste heat driven multi-mode flexible conversion cooling, heating and power integrated system is characterized by: The outlet of the high-pressure working fluid pump (10) is connected to the inlet of the high-pressure preheater (6), the outlet of the high-pressure preheater (6) is connected to the inlet of the high-pressure evaporator (5), the outlet of the high-pressure evaporator (5) is connected to the right inlet of the ejector a (7), and the bottom inlet of the ejector a (7) is connected to the bottom outlet of the gas-liquid separator (12) of the low-pressure circulation loop through the first outlet of the three-way valve b (13); The outlet of the ejector a (7) is connected to the low-temperature side inlet of the high-pressure superheater (4), the low-temperature side outlet of the high-pressure superheater (4) is connected to the inlet of the high-pressure turbine (8), and the high-pressure turbine (8) is connected to the high-pressure generator (9) via a coupling.

6. According to claim 5, a large temperature difference waste heat driven multi-mode flexible conversion cooling, heating and power integrated system is characterized by: The outlet of the low-pressure working fluid pump (18) is connected to the low-temperature side inlet of the low-pressure steam generator (11); The outlet of the low-pressure steam generator (11) is connected to the inlet of the gas-liquid separator (12), the top outlet of the gas-liquid separator (12) is connected to the inlet of the low-pressure turbine (14), and the low-pressure turbine (14) is connected to the low-pressure generator (15) via a coupling.

7. According to claim 6, a large temperature difference waste heat driven multi-mode flexible conversion cooling, heating and power integrated system is characterized by: The outlet of the throttle valve (23) is connected to the low-temperature side inlet of the refrigeration evaporator (22), and the low-temperature side outlet of the refrigeration evaporator (22) is connected to the bottom inlet of the ejector b (21), and the left inlet of the ejector b (21) is connected to the bottom outlet of the gas-liquid separator (12) of the low-pressure circulation loop through the second outlet of the three-way valve b (13).

8. According to claim 7, a large temperature difference waste heat driven multi-mode flexible conversion cooling, heating and power integrated system is characterized by: The outlet of the high-pressure turbine (8) is connected to a mixer (16) and to its right inlet, the top inlet of the mixer (16) is connected to the outlet of the low-pressure turbine (14), and the left inlet of the mixer (16) is connected to the outlet of the ejector b (21).

9. The large temperature difference waste heat driven multi-mode flexible conversion cooling, heating and power integrated system according to claim 8, characterized in that: The outlet of the mixer (16) is connected to the condenser (17) and is connected to the high-temperature side inlet thereof. The high-temperature side outlet of the condenser (17) is provided with a three-way valve c (19) and is connected to the inlet thereof. The first outlet of the three-way valve c (19) is divided into two branches, one branch is connected to the inlet of the low-pressure working fluid pump (18), and the other branch is connected to the inlet of the throttle valve (23) of the refrigeration unit.

10. The large temperature difference waste heat driven multi-mode flexible conversion cooling, heating and power integrated system according to claim 9, characterized in that: The system flexibly switches between multiple modes of heat, electricity, electric cooling, electric heating, and electric cooling and heating according to the different waste heat inlet temperatures, and realizes the proportional relationship of work, cooling and heat output by adjusting the working fluid flow ratio through valves. The cold side outlet of the condenser (17) is connected to the inlet of the three-way valve d (20), the first outlet of the three-way valve d (20) is connected to the cold side inlet of the heat exchanger b (26), and the cold side outlet of the heat exchanger b (26) is connected to the low-temperature hot water outlet.

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