A composite data center waste heat recovery system and control method

Abstract

This invention discloses a composite data center waste heat recovery system and control method, relating to the field of waste heat recovery technology. It includes a cooling module and a waste heat recovery module. The cooling module comprises a data center heat dissipation terminal, a chilled water circulation pump, a natural cooling heat exchanger, a cooling tower, and a cooling water circulation pump. The waste heat recovery module comprises a waste heat recovery heat exchanger, a low-temperature circulation pump, a variable frequency heat pump unit, a high-temperature circulation pump, a heating terminal, a refrigeration unit, a refrigeration circulation pump, and a refrigeration terminal. The waste heat recovery module also includes a first three-way valve, a second three-way valve, a third three-way valve, a fourth three-way valve, a third control valve, a fourth control valve, a fifth control valve, and a sixth control valve. Controlling these valves enables waste heat recovery for heating, cooling, or simultaneous heating and cooling. This invention offers diverse operating modes, enabling efficient waste heat recovery and utilization year-round, improving waste heat utilization efficiency, and achieving stable cooling in the waste heat recovery refrigeration system.

Description

Technical Field

[0001] This invention relates to the field of waste heat recovery technology, and in particular to a composite data center waste heat recovery system and control method. Background Technology

[0002] Data centers consume enormous amounts of energy and generate a significant amount of waste heat during operation. Directly releasing this waste heat would not only put immense pressure on the data center's cooling system but also result in a huge waste of energy. Currently, waste heat recovery technologies for data centers mainly include three approaches: waste heat recovery for heating, waste heat recovery for cooling, and waste heat recovery for power generation. Most existing solutions only employ one of these approaches to achieve waste heat recovery and utilization.

[0003] In waste heat recovery for heating, it is typically used for heating sources and domestic hot water applications. However, due to the limited heating season and low demand for domestic hot water, it cannot achieve year-round waste heat recovery and utilization, resulting in a low overall waste heat recovery rate. In waste heat recovery for cooling, this technology requires a stable heat source. However, fluctuations in data center load can lead to unstable waste heat supply, causing instability in the operation of the waste heat recovery cooling system.

[0004] In summary, existing data center waste heat recovery technologies generally suffer from drawbacks such as a single operating mode, low waste heat utilization rate, significant limitations on heat source stability, and inability to achieve efficient waste heat recovery and utilization throughout the year, making it difficult to meet the actual needs of data centers for efficient, stable, and diversified waste heat recovery and utilization. Summary of the Invention

[0005] The purpose of this invention is to provide a composite data center waste heat recovery system and control method to solve the problems existing in the prior art. It has diversified operation modes, can achieve efficient waste heat recovery and utilization throughout the year, improve waste heat utilization rate, and can achieve stable cooling of the waste heat recovery cooling system.

[0006] To achieve the above objectives, the present invention provides the following solution: This invention provides a composite data center waste heat recovery system, including a cooling module and a waste heat recovery module; The cooling module includes a data center heat dissipation terminal, a chilled water circulation pump, a natural cooling heat exchanger, a cooling tower, and a cooling water circulation pump; the waste heat recovery module includes a waste heat recovery heat exchanger, a low-temperature circulation pump, a variable frequency heat pump unit, a high-temperature circulation pump, a heat-using terminal, a refrigeration unit, a refrigeration circulation pump, and a refrigeration terminal. The data center heat dissipation terminal, the chilled water circulation pump, and the natural cooling heat exchanger are connected in sequence to form the first chilled water circuit; The data center heat dissipation terminal, the waste heat recovery heat exchanger, the chilled water circulation pump, and the natural cooling heat exchanger are connected in sequence to form a second chilled water circuit; A first control valve is provided on the pipeline connecting the outlet end of the data center heat dissipation terminal and the chilled water circulation pump; A second control valve is provided on the pipeline connecting the outlet end of the data center heat dissipation terminal and the waste heat recovery heat exchanger; The natural cooling heat exchanger, the cooling water circulation pump, and the cooling tower are connected in sequence to form a cooling water circuit; The waste heat recovery heat exchanger, the low-temperature circulating pump, and the variable frequency heat pump unit are connected in sequence to form a heating low-temperature circuit; The variable frequency heat pump unit, the high temperature circulating pump, and the heat-using terminal are connected in sequence to form a high temperature heating circuit. The waste heat recovery heat exchanger, the low-temperature circulating pump, and the refrigeration unit are connected in sequence to form a low-temperature refrigeration circuit; The variable frequency heat pump unit, the high temperature circulating pump, and the refrigeration unit are connected in sequence to form a high temperature refrigeration circuit; The refrigeration unit, the refrigeration circulation pump, and the refrigeration terminal are connected in sequence to form a refrigeration circuit; The waste heat recovery module also includes a first three-way valve, a second three-way valve, a third three-way valve, a fourth three-way valve, a third control valve, a fourth control valve, a fifth control valve, and a sixth control valve; The first port of the first three-way valve is connected to the outlet end of the cryogenic circulating pump, the second port of the first three-way valve is connected to the variable frequency heat pump unit, and the third port of the first three-way valve is connected to the first port of the third three-way valve. The first port of the second three-way valve is connected to the waste heat recovery heat exchanger, the second port of the second three-way valve is connected to the variable frequency heat pump unit, and the third port of the second three-way valve is connected to the first port of the fourth three-way valve. The first port of the third control valve is connected to the outlet end of the high-temperature circulating pump, and the second port of the third control valve is connected to the heat-consuming terminal; the first port of the fourth control valve is connected to the variable frequency heat pump unit, and the second port of the fourth control valve is connected to the heat-consuming terminal. The first port of the fifth control valve is connected to the outlet of the high-temperature circulating pump, the second port of the fifth control valve is connected to the second port of the third three-way valve, and the third port of the third three-way valve is connected to the refrigeration unit. The first port of the sixth control valve is connected to the variable frequency heat pump unit, the second port of the sixth control valve is connected to the second port of the fourth three-way valve, and the third port of the fourth three-way valve is connected to the refrigeration unit.

[0007] The present invention also provides a control method for the above-described composite data center waste heat recovery system, including a cooling system cooling control mode, a waste heat recovery cooling control mode, and a hybrid cooling control mode; The cooling system cooling control mode is as follows: the first control valve is open, the second control valve is closed, and the cooling water at the heat dissipation terminal of the data center is cooled by the natural cooling heat exchanger. The waste heat recovery cooling control mode is as follows: the first control valve is closed, the second control valve is open, and the cooling water at the heat dissipation terminal of the data center is cooled by the waste heat recovery heat exchanger. The hybrid cooling control mode: the opening of the first control valve and the second control valve is adjusted according to the demand for waste heat. Part of the cooling water at the heat dissipation terminal of the data center is cooled by the natural cooling heat exchanger, and the other part is cooled by the waste heat recovery heat exchanger.

[0008] In one embodiment, cooling via the waste heat recovery heat exchanger includes waste heat recovery heating and waste heat recovery cooling. Waste heat recovery heating: Waste heat from the data center is supplied to the variable frequency heat pump unit through the heating low-temperature circuit. The variable frequency heat pump unit further increases the temperature of the waste heat and then delivers it to the heat-using terminal through the heating high-temperature circuit. Waste heat recovery cooling: When the waste heat generated by the data center load meets the heat required by the cooling unit and the waste heat fluctuation is stable, the waste heat of the data center is supplied to the cooling unit through the low temperature cooling circuit, and the cooling capacity is output to the cooling terminal through the cooling circuit. When the waste heat generated by the data center load does not meet the heat required by the cooling unit, or when the waste heat fluctuates unstablely, the waste heat from the data center passes through the heating low-temperature circuit and then through the cooling high-temperature circuit to provide stable heat to the cooling unit, and outputs cooling capacity to the cooling terminal through the cooling circuit.

[0009] The present invention achieves the following technical effects compared to the prior art: The composite data center waste heat recovery system and control method provided by this invention can realize independent waste heat recovery heating, independent waste heat recovery cooling, or joint operation of waste heat recovery heating and cooling. The operation mode is diversified. When the data center load fluctuates greatly or the waste heat is insufficient, the variable frequency heat pump unit can provide stable heat for the waste heat recovery cooling cycle, realize stable cooling of the waste heat recovery cooling system, and fully recover waste heat during the year-round operation of the data center, thereby improving the waste heat utilization rate. Attached Figure Description

[0010] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0011] Figure 1 This is a system block diagram of the composite data center waste heat recovery system in an embodiment of the present invention.

[0012] In the diagram: 1-Data center heat dissipation terminal, 2-Chiller water circulation pump, 3-Natural cooling heat exchanger, 4-Cooling tower, 5-Cooling water circulation pump, 6-Waste heat recovery heat exchanger, 7-Low temperature circulation pump, 8-Variable frequency heat pump unit, 9-High temperature circulation pump, 10-Heating terminal, 11-Refrigeration unit, 12-Refrigeration circulation pump, 13-Refrigeration terminal, 14-First control valve, 15-Second control valve, 16-First three-way valve, 17-Second three-way valve, 18-Third three-way valve, 19-Fourth three-way valve, 20-Third control valve, 21-Fourth control valve, 22-Fifth control valve, 23-Sixth control valve. Detailed Implementation

[0013] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0014] The purpose of this invention is to provide a composite data center waste heat recovery system and control method to solve the problems existing in the prior art. It has diversified operation modes, can achieve efficient waste heat recovery and utilization throughout the year, improve waste heat utilization rate, and can achieve stable cooling of the waste heat recovery cooling system.

[0015] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0016] Example 1 like Figure 1 As shown, this embodiment provides a composite data center waste heat recovery system, including a cooling module and a waste heat recovery module; The cooling module includes a data center heat dissipation terminal 1, a chilled water circulation pump 2, a natural cooling heat exchanger 3, a cooling tower 4, and a cooling water circulation pump 5; the waste heat recovery module includes a waste heat recovery heat exchanger 6, a low-temperature circulation pump 7, a variable frequency heat pump unit 8, a high-temperature circulation pump 9, a heat-using terminal 10, a refrigeration unit 11, a refrigeration circulation pump 12, and a refrigeration terminal 13. The data center heat dissipation terminal 1, chilled water circulation pump 2 and natural cooling heat exchanger 3 are connected in sequence to form the first chilled water circuit; The data center heat dissipation terminal 1, waste heat recovery heat exchanger 6, chilled water circulation pump 2 and natural cooling heat exchanger 3 are connected in sequence to form a second chilled water circuit; A first control valve 14 is provided on the pipeline connecting the outlet end of the data center heat dissipation terminal 1 and the chilled water circulation pump 2; A second control valve 15 is provided on the pipeline connecting the outlet end of the data center heat dissipation terminal 1 and the waste heat recovery heat exchanger 6; The natural cooling heat exchanger 3, the cooling water circulation pump 5, and the cooling tower 4 are connected in sequence to form a cooling water circuit; Waste heat recovery heat exchanger 6, low-temperature circulating pump 7 and variable frequency heat pump unit 8 are connected in sequence to form a heating low-temperature circuit. The variable frequency heat pump unit 8, the high temperature circulating pump 9, and the heat-using terminal 10 are connected in sequence to form a high temperature heating circuit. Waste heat recovery heat exchanger 6, low temperature circulating pump 7 and refrigeration unit 11 are connected in sequence to form a refrigeration low temperature circuit; refrigeration unit 11 is an absorption refrigeration unit. The variable frequency heat pump unit 8, the high temperature circulating pump 9, and the refrigeration unit 11 are connected in sequence to form a high temperature refrigeration circuit. The refrigeration unit 11, the refrigeration circulation pump 12, and the refrigeration terminal 13 are connected in sequence to form a refrigeration circuit; The waste heat recovery module also includes a first three-way valve 16, a second three-way valve 17, a third three-way valve 18, a fourth three-way valve 19, a third control valve 20, a fourth control valve 21, a fifth control valve 22, and a sixth control valve 23; the first three-way valve 16, the second three-way valve 17, the third three-way valve 18, and the fourth three-way valve 19 are all two-position three-way valves; The first port of the first three-way valve 16 is connected to the outlet end of the low-temperature circulating pump 7, the second port of the first three-way valve 16 is connected to the variable frequency heat pump unit 8, and the third port of the first three-way valve 16 is connected to the first port of the third three-way valve 18. The first port of the second three-way valve 17 is connected to the waste heat recovery heat exchanger 6, the second port of the second three-way valve 17 is connected to the variable frequency heat pump unit 8, and the third port of the second three-way valve 17 is connected to the first port of the fourth three-way valve 19. The first port of the third control valve 20 is connected to the outlet end of the high-temperature circulating pump 9, and the second port of the third control valve 20 is connected to the heat terminal 10; the first port of the fourth control valve 21 is connected to the variable frequency heat pump unit 8, and the second port of the fourth control valve 21 is connected to the heat terminal 10. The first port of the fifth control valve 22 is connected to the outlet end of the high-temperature circulating pump 9, the second port of the fifth control valve 22 is connected to the second port of the third three-way valve 18, and the third port of the third three-way valve 18 is connected to the refrigeration unit 11. The first port of the sixth control valve 23 is connected to the variable frequency heat pump unit 8, the second port of the sixth control valve 23 is connected to the second port of the fourth three-way valve 19, and the third port of the fourth three-way valve 19 is connected to the refrigeration unit 11.

[0017] The composite data center waste heat recovery system provided in this embodiment achieves year-round waste heat recovery and utilization by coupling a heating and cooling system, thereby improving waste heat utilization efficiency. This waste heat recovery system delivers heat when there is a heating demand and cooling capacity when there is a cooling demand. It can also simultaneously output heat and cooling capacity, offering diverse operating modes. Furthermore, when the data center load fluctuates significantly or the waste heat is insufficient, the variable frequency heat pump unit 8 can provide stable heat for the waste heat recovery cooling cycle, achieving stable cooling for the waste heat recovery cooling system.

[0018] Example 2 This embodiment provides a control method for a composite data center waste heat recovery system as described in Embodiment 1, including a cooling system cooling control mode, a waste heat recovery cooling control mode, and a hybrid cooling control mode; Cooling system cooling control mode: First control valve 14 is open, second control valve 15 is closed, and the cooling water of the data center heat dissipation terminal 1 is cooled by natural cooling heat exchanger 3. Waste heat recovery cooling control mode: the first control valve 14 is closed, the second control valve 15 is open, and the cooling water of the data center heat dissipation terminal 1 is cooled through the waste heat recovery heat exchanger 6. Hybrid cooling control mode: Based on the demand for waste heat, the opening of the first control valve 14 and the second control valve 15 are adjusted. Part of the cooling water of the data center heat dissipation terminal 1 is cooled by the natural cooling heat exchanger 3, and the other part is cooled by the waste heat recovery heat exchanger 6, so as to realize the on-demand scheduling of waste heat.

[0019] When cooling is performed through the waste heat recovery heat exchanger 6, it includes waste heat recovery heating and waste heat recovery refrigeration. Waste heat recovery heating: Waste heat from the data center is supplied to the variable frequency heat pump unit 8 through a low-temperature heating loop. The variable frequency heat pump unit 8 further increases the temperature of the waste heat and then delivers it to the heat-using terminal 10 through a high-temperature heating loop. The heat-using terminal 10 includes heating sources, domestic hot water, and agricultural greenhouses, among other usage scenarios. Waste heat recovery cooling: The control system makes corresponding controls based on the size of the data center load and the waste heat generated by load fluctuations and the amplitude of waste heat fluctuations. When the waste heat generated by the data center load meets the heat required by the chiller unit 11 and the waste heat fluctuation is stable (small), the waste heat of the data center is supplied to the chiller unit 11 through the low temperature cooling circuit, and the cooling capacity is output to the cooling terminal 13 through the cooling circuit; the cooling terminal 13 can be used for office space cooling and data center IT equipment cooling and other application scenarios. When the waste heat generated by the data center load is insufficient to meet the heat requirements of the chiller unit 11, or when the waste heat fluctuates significantly, the waste heat from the data center provides stable heat to the chiller unit 11 through a low-temperature heating circuit and then a high-temperature cooling circuit, and outputs cooling capacity to the cooling terminal 13 through the cooling circuit. Small amounts of waste heat or waste heat with large fluctuations from the data center are heated by the variable frequency heat pump unit 8 and then output stable and reliable heat to the chiller unit 11, ensuring stable cooling of the waste heat recovery cooling system.

[0020] Waste heat recovery heating systems and waste heat recovery cooling systems can operate independently or in combination, enabling independent waste heat recovery heating, independent waste heat recovery cooling, and simultaneous waste heat recovery heating and cooling.

[0021] When heating independently, the first three-way valve 16 and the second three-way valve 17 connect the low-temperature circulating pump 7, the variable frequency heat pump unit 8 and the waste heat recovery heat exchanger 6, the third control valve 20 and the fourth control valve 21 are opened, and the fifth control valve 22 and the sixth control valve 23 are closed, connecting the high-temperature circulating pump 9, the heat terminal 10 and the variable frequency heat pump unit 8. When the independent refrigeration is in operation and the waste heat fluctuation is stable (small), the first three-way valve 16, the second three-way valve 17, the third three-way valve 18 and the fourth three-way valve 19 will connect the low temperature circulating pump 7, the refrigeration unit 11 and the waste heat recovery heat exchanger 6. When the independent refrigeration is unstable (large) and the waste heat fluctuation is large, the first three-way valve 16 and the second three-way valve 17 connect the low-temperature circulating pump 7, the variable frequency heat pump unit 8 and the waste heat recovery heat exchanger 6, the third control valve 20 and the fourth control valve 21 are closed, the fifth control valve 22 and the sixth control valve 23 are opened, and the third three-way valve 18 and the fourth three-way valve 19 connect the high-temperature circulating pump 9, the refrigeration unit 11 and the variable frequency heat pump unit 8. Simultaneously, when waste heat is recovered for heating and cooling, the first three-way valve 16 and the second three-way valve 17 connect the low-temperature circulating pump 7, the variable frequency heat pump unit 8, and the waste heat recovery heat exchanger 6. The third control valve 20, the fourth control valve 21, the fifth control valve 22, and the sixth control valve 23 are opened. The third three-way valve 18 connects the fifth control valve 22 and the refrigeration unit 11. The fourth three-way valve 19 connects the sixth control valve 23 and the refrigeration unit 11. The variable frequency heat pump unit 8 and the high-temperature circulating pump 9 are connected to the heat terminal 10 and the refrigeration unit 11, respectively.

[0022] Specific examples have been used to illustrate the principles and implementation methods of this invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of this invention. Furthermore, those skilled in the art will recognize that, based on the ideas of this invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this invention.

Claims

1. A composite data center waste heat recovery system, characterized in that: Includes a cooling module and a waste heat recovery module; The cooling module includes a data center heat dissipation terminal, a chilled water circulation pump, a natural cooling heat exchanger, a cooling tower, and a cooling water circulation pump; the waste heat recovery module includes a waste heat recovery heat exchanger, a low-temperature circulation pump, a variable frequency heat pump unit, a high-temperature circulation pump, a heat-using terminal, a refrigeration unit, a refrigeration circulation pump, and a refrigeration terminal. The data center heat dissipation terminal, the chilled water circulation pump, and the natural cooling heat exchanger are connected in sequence to form the first chilled water circuit; The data center heat dissipation terminal, the waste heat recovery heat exchanger, the chilled water circulation pump, and the natural cooling heat exchanger are connected in sequence to form a second chilled water circuit; A first control valve is provided on the pipeline connecting the outlet end of the data center heat dissipation terminal and the chilled water circulation pump; A second control valve is provided on the pipeline connecting the outlet end of the data center heat dissipation terminal and the waste heat recovery heat exchanger; The natural cooling heat exchanger, the cooling water circulation pump, and the cooling tower are connected in sequence to form a cooling water circuit; The waste heat recovery heat exchanger, the low-temperature circulating pump, and the variable frequency heat pump unit are connected in sequence to form a heating low-temperature circuit; The variable frequency heat pump unit, the high temperature circulating pump, and the heat-using terminal are connected in sequence to form a high temperature heating circuit. The waste heat recovery heat exchanger, the low-temperature circulating pump, and the refrigeration unit are connected in sequence to form a low-temperature refrigeration circuit; The variable frequency heat pump unit, the high temperature circulating pump, and the refrigeration unit are connected in sequence to form a high temperature refrigeration circuit; The refrigeration unit, the refrigeration circulation pump, and the refrigeration terminal are connected in sequence to form a refrigeration circuit; The waste heat recovery module also includes a first three-way valve, a second three-way valve, a third three-way valve, a fourth three-way valve, a third control valve, a fourth control valve, a fifth control valve, and a sixth control valve; The first port of the first three-way valve is connected to the outlet end of the cryogenic circulating pump, the second port of the first three-way valve is connected to the variable frequency heat pump unit, and the third port of the first three-way valve is connected to the first port of the third three-way valve. The first port of the second three-way valve is connected to the waste heat recovery heat exchanger, the second port of the second three-way valve is connected to the variable frequency heat pump unit, and the third port of the second three-way valve is connected to the first port of the fourth three-way valve. The first port of the third control valve is connected to the outlet end of the high-temperature circulating pump, and the second port of the third control valve is connected to the heat-consuming terminal; the first port of the fourth control valve is connected to the variable frequency heat pump unit, and the second port of the fourth control valve is connected to the heat-consuming terminal. The first port of the fifth control valve is connected to the outlet of the high-temperature circulating pump, the second port of the fifth control valve is connected to the second port of the third three-way valve, and the third port of the third three-way valve is connected to the refrigeration unit. The first port of the sixth control valve is connected to the variable frequency heat pump unit, the second port of the sixth control valve is connected to the second port of the fourth three-way valve, and the third port of the fourth three-way valve is connected to the refrigeration unit.

2. The control method for the composite data center waste heat recovery system as described in claim 1, characterized in that, This includes cooling system cooling control modes, waste heat recovery cooling control modes, and hybrid cooling control modes; The cooling system cooling control mode is as follows: the first control valve is open, the second control valve is closed, and the cooling water at the heat dissipation terminal of the data center is cooled by the natural cooling heat exchanger. The waste heat recovery cooling control mode is as follows: the first control valve is closed, the second control valve is open, and the cooling water at the heat dissipation terminal of the data center is cooled by the waste heat recovery heat exchanger. The hybrid cooling control mode: the opening of the first control valve and the second control valve is adjusted according to the demand for waste heat. Part of the cooling water at the heat dissipation terminal of the data center is cooled by the natural cooling heat exchanger, and the other part is cooled by the waste heat recovery heat exchanger.

3. The control method for the composite data center waste heat recovery system according to claim 2, characterized in that: When cooling is performed through the waste heat recovery heat exchanger, it includes waste heat recovery heating and waste heat recovery cooling. Waste heat recovery heating: Waste heat from the data center is supplied to the variable frequency heat pump unit through the heating low-temperature circuit. The variable frequency heat pump unit further increases the temperature of the waste heat and then delivers it to the heat-using terminal through the heating high-temperature circuit. Waste heat recovery cooling: When the waste heat generated by the data center load meets the heat required by the cooling unit and the waste heat fluctuation is stable, the waste heat of the data center is supplied to the cooling unit through the low temperature cooling circuit, and the cooling capacity is output to the cooling terminal through the cooling circuit. When the waste heat generated by the data center load does not meet the heat required by the cooling unit, or when the waste heat fluctuates unstablely, the waste heat from the data center passes through the heating low-temperature circuit and then through the cooling high-temperature circuit to provide stable heat to the cooling unit, and outputs cooling capacity to the cooling terminal through the cooling circuit.

Images