Heating 300 ℃ type low-grade heat recovery super heat pump unit and operation method thereof

Abstract

The application discloses a heating 300 DEG C type low-grade heat recovery super heat pump unit and a running method thereof. The unit is composed of a multi-stage heat exchanger, a multi-stage compressor, a multi-stage throttling device and a multi-stage circulating pump. Industrial waste heat or air energy is used as a cold source to produce two high-temperature heat sources, and high-temperature hot water or steam up to 300 DEG C can be produced. The internal circulating medium of the unit is composed of medium A, medium B, medium C, medium D and medium E. High-efficiency heat exchange is realized through phase change heat exchange of different working media in each heat exchanger. The innovative process and innovative medium can realize flexible and high-efficiency heat exchange with a large temperature difference, and the heating temperature is significantly improved compared with the prior art.

Description

Technical Field

[0001] This invention belongs to the field of energy utilization technology, and in particular relates to a heat pump unit that extracts heat from air, waste heat, etc. to produce high-temperature hot water or steam. Background Technology

[0002] Currently, energy efficiency in my country's industrial sector is less than 50%, and a large amount of low-grade industrial waste heat remains unutilized, leading to low energy efficiency and high carbon emissions. Extracting heat from the air and waste heat to produce hot water or steam has significant energy-saving and carbon-reducing effects. Meanwhile, heat pump technology is a device with good energy-saving performance; however, existing heat pump technologies, whether absorption or compression, are limited to operating in a relatively low temperature range due to factors such as circulation process, circulating medium, and heat exchange efficiency, thus failing to meet the heating temperature requirements of various scenarios.

[0003] Against this backdrop, the invention proposes an innovative thermodynamic cycle method that utilizes low-grade energy sources such as air and waste heat to obtain high-temperature hot water or steam, which can be used to heat various production processes, with a temperature increase of over 200°C and a maximum heating temperature of 300°C, meeting the needs of most industrial waste heat recovery, renewable energy power consumption, high-temperature heat storage, and centralized heating scenarios. Summary of the Invention

[0004] This invention proposes a low-grade heat recovery super heat pump unit with a heating capacity of 300℃ and its operation method. It employs a multi-stage heat and mass transfer process to achieve a wide range of temperature increases and heating temperatures, significantly surpassing existing related technologies and greatly expanding the application scenarios and system efficiency of heat pump technology. The unit utilizes a multi-medium internal circulation method, employing novel media that significantly improve heat exchange efficiency compared to existing technologies, thereby reducing equipment size.

[0005] A 300℃ low-grade heat recovery super heat pump unit comprises heat exchanger A (1), compressor A (2), throttling device A (3), heat exchanger B (4), compressor B (5), heat exchanger C (6), throttling device B (7), compressor C (8), throttling device C (9), heat exchanger D (10), circulating pump A (11), heat exchanger H (12), heat exchanger E (13), heat exchanger F (14), throttling device D (15), compressor D (16), heat exchanger G (17), circulating pump B (18), throttling device E (19), cold source inlet (20), cold source outlet (21), heat source B outlet (22), heat source B inlet (23), heat source A outlet (24), and heat source A inlet (25). Heat source A outlet (24) and heat source A inlet (25) are connected to heat exchanger A (1), compressor A (2) is connected to heat exchanger A (1) and heat exchanger B (4), throttling device A (3) is connected to heat exchanger A (1) and heat exchanger B (4), heat exchanger B (4) is connected to compressor A (2), throttling device A (3), circulating pump A (11), heat exchanger H (12) and compressor B (5), compressor B (5) is connected to heat exchanger B (4) and heat exchanger C (6), throttling device B ( 7) Connected to heat exchanger C(6) and heat exchanger E(13), compressor C(8) is connected to heat exchanger C(6), throttling device C(9) and heat exchanger D(10), heat exchanger D(10) is connected to compressor C(8), throttling device C(9), throttling device E(19), cold source inlet (20) and cold source outlet (21), throttling device C(9) is connected to compressor C(8), heat exchanger D(10) and throttling device E(19), circulating pump B(18) is connected to heat exchanger C(6) and heat exchanger E(13). Heater F(14) is connected; circulating pump A(11) is connected to heat exchanger B(4) and heat exchanger H(12); heat exchanger H(12) is connected to circulating pump A(11), heat exchanger B(4) and heat exchanger E(13); heat exchanger E(13) is connected to heat exchanger H(12), throttling device B(7), throttling device E(19) and heat exchanger F(14); heat exchanger F(14) is connected to circulating pump B(18), heat exchanger E(13), compressor D(16) and throttling device D(15). Compressor D (16) is connected to heat exchanger F (14) and heat exchanger G (17). Throttling device D (15) is connected to heat exchanger F (14) and heat exchanger G (17). Heat exchanger G (17) is connected to compressor D (16), throttling device D (15), heat source B outlet (22) and heat source B inlet (23). Cold source inlet (20) and cold source outlet (21) are connected to heat exchanger D (10). Heat source B outlet (22) and heat source B inlet (23) are connected to heat exchanger G (17).

[0006] The internal circulating medium of this unit consists of medium A, medium B, medium C, medium D, and medium E. Medium A is inorganic salt, ammonia, or Freon; medium B is water, alcohol, or Freon; medium C is a mixture of water and Freon (HD06), ammonia, or carbon dioxide; medium D is water, Freon, ammonia, or carbon dioxide; and medium E is water, Freon, ammonia, or carbon dioxide. The Freon mixture (HD06) consists of three Freon types: R365mfc at a ratio of 2%-85%, R1233zd at a ratio of 1%-95%, and R601 at a ratio of 1%-90%. Medium C circulates in heat exchanger A(1), compressor A(2), throttling device A(3) and heat exchanger B(4). Medium B circulates in heat exchanger F(14), circulating pump B(18), heat exchanger C(6) and compressor B(5). The mixture of medium A and medium B circulates in heat exchanger B(4), heat exchanger H(12), heat exchanger E(13) and circulating pump A(11). Medium D circulates in compressor C(8), heat exchanger C(6), throttling device B(7), heat exchanger E(13), throttling device E(19) and heat exchanger D(10). Part of medium D after passing through throttling device E(19) enters compressor C(8), and the rest of medium D enters heat exchanger D(10). Medium E circulates in compressor D(16), heat exchanger G(17), throttling device D(15) and heat exchanger F(14).

[0007] The unit's circulation principle is as follows: The mixture of medium A and medium B inside heat exchanger B(4) absorbs the vapor of medium B and releases heat to heat medium C, changing it from liquid medium C to gaseous medium C. The gaseous medium C is compressed by compressor A(2) and then enters heat exchanger A(1), changing from gaseous medium C to liquid medium C. The released heat is used to heat heat source A. The mixture of medium A and medium B absorbs medium B and then enters heat exchanger E(13) through heat exchanger H(12). The mixture of medium A and medium B is heated by medium D in heat exchanger E(13) and releases gaseous medium B. Medium B enters heat exchanger F(14), and the mixture of medium A and medium B, which releases part of medium B, then passes through heat exchanger H(12) and circulating pump A(11) before entering heat exchanger B(4). The gaseous medium B becomes liquid in heat exchanger F(14), and the released heat is used to heat medium E. Medium E is heated in heat exchanger F(14) and changes from liquid to gas. Liquid medium B then passes through circulating pump B(18) before entering heat exchanger C(6). Liquid medium B is heated by medium D in heat exchanger C(6) and becomes gaseous medium B. Gaseous medium B is compressed by compressor B(5) before entering... After heat exchanger B(4), the mixture of medium A and medium B is absorbed and circulated repeatedly. The gaseous medium D is cooled and turned into liquid medium D in heat exchanger C(6) and heat exchanger E(13) in sequence. After passing through throttling device E(19), part of the liquid medium D passes through throttling device C(9) and enters compressor C(8). The remaining liquid medium D enters heat exchanger D(10) and changes from liquid to gas to extract heat from the cold source. The gaseous medium D in heat exchanger D(10) and the medium D passing through throttling device C(9) are mixed in compressor C(8) to complete the compression process and pass through in sequence in the form of gaseous medium D. Heat exchangers C(6) and E(13) gradually become liquid medium D and release heat. The distribution ratio of medium D into throttling device C(9) and heat exchanger D(10) is determined according to the cold source temperature and the outlet temperature and pressure of compressor C(8). Medium E is heated by medium B in heat exchanger F(14) and changes from liquid medium E to gaseous medium E. After being compressed by compressor D(16), gaseous medium E changes from gaseous to liquid in heat exchanger G(17) and releases heat to heat source B. Liquid medium E enters heat exchanger F(14) after passing through throttling device D(15) and circulates repeatedly. Attached Figure Description

[0008] Figure 1 This is a system diagram of a low-grade heat recovery super heat pump unit with a heating capacity of 300℃.

[0009] Figure label:

[0010] 1-Heat exchanger A, 2-Compressor A, 3-Throttling device A, 4-Heat exchanger B, 5-Compressor B, 6-Heat exchanger C, 7-Throttling device B, 8-Compressor C, 9-Throttling device C, 10-Heat exchanger D, 11-Circulating pump A, 12-Heat exchanger H, 13-Heat exchanger E, 14-Heat exchanger F, 15-Throttling device D, 16-Compressor D, 17-Heat exchanger G, 18-Circulating pump B, 19-Throttling device E, 20-Cold source inlet, 21-Cold source outlet, 22-Heat source B outlet, 23-Heat source B inlet, 24-Heat source A outlet, 25-Heat source A inlet. Detailed Implementation

[0011] In this embodiment, the inlet temperature of heat source A is 230°C, the outlet temperature of heat source A is 300°C, the inlet temperature of cold source is 80°C, the outlet temperature of cold source is 40°C, the inlet temperature of heat source B is 30°C, and the outlet temperature of heat source B is 70°C. The unit consists of heat exchanger A (1), compressor A (2), throttling device A (3), heat exchanger B (4), compressor B (5), heat exchanger C (6), throttling device B (7), compressor C (8), throttling device C (9), heat exchanger D (10), circulating pump A (11), heat exchanger H (12), heat exchanger E (13), heat exchanger F (14), throttling device D (15), compressor D (16), heat exchanger G (17), circulating pump B (18), throttling device E (19), cold source inlet (20), cold source outlet (21), heat source B outlet (22), heat source B inlet (23), heat source A outlet (24), and heat source A inlet (25). Heat source A outlet (24) and heat source A inlet (25) are connected to heat exchanger A (1), compressor A (2) is connected to heat exchanger A (1) and heat exchanger B (4), throttling device A (3) is connected to heat exchanger A (1) and heat exchanger B (4), heat exchanger B (4) is connected to compressor A (2), throttling device A (3), circulating pump A (11), heat exchanger H (12) and compressor B (5), compressor B (5) is connected to heat exchanger B (4) and heat exchanger C (6), throttling device B ( 7) Connected to heat exchanger C(6) and heat exchanger E(13), compressor C(8) is connected to heat exchanger C(6), throttling device C(9) and heat exchanger D(10), heat exchanger D(10) is connected to compressor C(8), throttling device C(9), throttling device E(19), cold source inlet (20) and cold source outlet (21), throttling device C(9) is connected to compressor C(8), heat exchanger D(10) and throttling device E(19), circulating pump B(18) is connected to heat exchanger C(6) and heat exchanger E(13). Heater F(14) is connected; circulating pump A(11) is connected to heat exchanger B(4) and heat exchanger H(12); heat exchanger H(12) is connected to circulating pump A(11), heat exchanger B(4) and heat exchanger E(13); heat exchanger E(13) is connected to heat exchanger H(12), throttling device B(7), throttling device E(19) and heat exchanger F(14); heat exchanger F(14) is connected to circulating pump B(18), heat exchanger E(13), compressor D(16) and throttling device D(15). Compressor D (16) is connected to heat exchanger F (14) and heat exchanger G (17). Throttling device D (15) is connected to heat exchanger F (14) and heat exchanger G (17). Heat exchanger G (17) is connected to compressor D (16), throttling device D (15), heat source B outlet (22) and heat source B inlet (23). Cold source inlet (20) and cold source outlet (21) are connected to heat exchanger D (10). Heat source B outlet (22) and heat source B inlet (23) are connected to heat exchanger G (17).

[0012] The internal circulating medium of this unit consists of medium A, medium B, medium C, medium D and medium E. Medium A is methylpyrrolidone, medium B is difluoroethanol, medium C is a Freon mixed working medium HD06, and the working medium HD06 is composed of R365mfc at a ratio of 36%, R1233zd at a ratio of 45% and R601 at a ratio of 19%. Medium D is carbon dioxide and medium E is Freon R410A. Medium C circulates in heat exchanger A(1), compressor A(2), throttling device A(3) and heat exchanger B(4). Medium B circulates in heat exchanger F(14), circulating pump B(18), heat exchanger C(6) and compressor B(5). The mixture of medium A and medium B circulates in heat exchanger B(4), heat exchanger H(12), heat exchanger E(13) and circulating pump A(11). Medium D circulates in compressor C(8), heat exchanger C(6), throttling device B(7), heat exchanger E(13), throttling device E(19) and heat exchanger D(10). Part of medium D after passing through throttling device E(19) enters compressor C(8), and the rest of medium D enters heat exchanger D(10). Medium E circulates in compressor D(16), heat exchanger G(17), throttling device D(15) and heat exchanger F(14).

[0013] The unit's circulation principle is as follows: The mixture of medium A and medium B inside heat exchanger B(4) absorbs the vapor of medium B and releases heat to heat medium C, changing it from liquid medium C to gaseous medium C. The gaseous medium C is compressed by compressor A(2) and then enters heat exchanger A(1), changing from gaseous medium C to liquid medium C. The released heat is used to heat heat source A. The mixture of medium A and medium B absorbs medium B and then enters heat exchanger E(13) through heat exchanger H(12). The mixture of medium A and medium B is heated by medium D in heat exchanger E(13) and releases gaseous medium B. Medium B enters heat exchanger F(14), and the mixture of medium A and medium B, which releases part of medium B, then passes through heat exchanger H(12) and circulating pump A(11) before entering heat exchanger B(4). The gaseous medium B becomes liquid in heat exchanger F(14), and the released heat is used to heat medium E. Medium E is heated in heat exchanger F(14) and changes from liquid to gas. Liquid medium B then passes through circulating pump B(18) before entering heat exchanger C(6). Liquid medium B is heated by medium D in heat exchanger C(6) and becomes gaseous medium B. Gaseous medium B passes through compressor B(5). After compression, the medium D enters heat exchanger B(4) and is absorbed by the mixture of medium A and medium B in a reciprocating cycle. The gaseous medium D is cooled and becomes liquid medium D in heat exchanger C(6) and heat exchanger E(13) in sequence. After passing through throttling device E(19), part of the liquid medium D passes through throttling device C(9) and enters compressor C(8). The remaining liquid medium D enters heat exchanger D(10) and changes from liquid to gas to extract heat from the cold source. The gaseous medium D in heat exchanger D(10) and the medium D passing through throttling device C(9) are mixed in compressor C(8) to complete the compression process and become gaseous. Medium D passes through heat exchanger C (6) and heat exchanger E (13) in sequence and gradually becomes liquid medium D to release heat. The proportions of medium D entering throttling device C (9) and heat exchanger D (10) are 35% and 65%, respectively. Medium E is heated by medium B in heat exchanger F (14) and changes from liquid medium E to gaseous medium E. After being compressed by compressor D (16), gaseous medium E changes from gaseous to liquid in heat exchanger G (17) to release heat and heat source B. Liquid medium E enters heat exchanger F (14) after passing through throttling device D (15) and repeats the cycle.

[0014] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A 300℃ low-grade heat recovery super heat pump unit and its operation method, characterized in that: The unit includes heat exchanger A (1), compressor A (2), throttling device A (3), heat exchanger B (4), compressor B (5), heat exchanger C (6), throttling device B (7), compressor C (8), throttling device C (9), heat exchanger D (10), circulating pump A (11), heat exchanger H (12), heat exchanger E (13), heat exchanger F (14), throttling device D (15), compressor D (16), heat exchanger G (17), circulating pump B (18), throttling device E (19), cold source inlet (20), cold source outlet (21), heat source B outlet (22), heat source B inlet (23), heat source A outlet (24), and heat source A inlet (25). The system consists of a heat source A outlet (24) and heat source A inlet (25) connected to heat exchanger A (1), compressor A (2) connected to heat exchanger A (1) and heat exchanger B (4), throttling device A (3) connected to heat exchanger A (1) and heat exchanger B (4), heat exchanger B (4) connected to compressor A (2), throttling device A (3), circulating pump A (11), heat exchanger H (12) and compressor B (5), compressor B (5) connected to heat exchanger B (4) and heat exchanger C (6), throttling device B (7) connected to heat exchanger C (6) and heat exchanger E (13), and compressor C (8) connected to heat exchanger C (6), throttling device C (9) and heat exchanger D (10). The heat exchanger D(10) is connected to the compressor C(8), the throttling device C(9), the throttling device E(19), the cold source inlet (20), and the cold source outlet (21). The throttling device C(9) is connected to the compressor C(8), the heat exchanger D(10), and the throttling device E(19). The circulating pump B(18) is connected to the heat exchanger C(6) and the heat exchanger F(14). The circulating pump A(11) is connected to the heat exchanger B(4) and the heat exchanger H(12). The heat exchanger H(12) is connected to the circulating pump A(11), the heat exchanger B(4), and the heat exchanger E(13). The heat exchanger E(13) is connected to the heat exchanger H(12), the throttling device B(7), the throttling device E(19), and the cold source outlet (21). Heat exchanger F(14) is connected to circulating pump B(18), heat exchanger E(13), compressor D(16) and throttling device D(15). Compressor D(16) is connected to heat exchanger F(14) and heat exchanger G(17). Throttling device D(15) is connected to heat exchanger F(14) and heat exchanger G(17). Heat exchanger G(17) is connected to compressor D(16), throttling device D(15), heat source B outlet (22) and heat source B inlet (23). Cold source inlet (20) and cold source outlet (21) are connected to heat exchanger D(10). Heat source B outlet (22) and heat source B inlet (23) are connected to heat exchanger G(17).The unit's circulation principle is as follows: The mixture of medium A and medium B inside heat exchanger B(4) absorbs the vapor of medium B and releases heat to heat medium C, changing it from liquid medium C to gaseous medium C. After being compressed by compressor A(2), gaseous medium C enters heat exchanger A(1) and changes from gaseous medium C to liquid medium C. The released heat is used to heat heat source A. The mixture of medium A and medium B absorbs medium B and then enters heat exchanger E(13) through heat exchanger H(12). The mixture of medium A and medium B is heated by medium D in heat exchanger E(13). Afterwards, gaseous medium B is released and enters heat exchanger F (14). The mixture of medium A and medium B, which has released part of medium B, then passes through heat exchanger H (12) and circulating pump A (11) before entering heat exchanger B (4). In heat exchanger F (14), gaseous medium B becomes liquid and the released heat is used to heat medium E. Medium E is heated in heat exchanger F (14) and changes from liquid to gas. Liquid medium B then passes through circulating pump B (18) before entering heat exchanger C (6). In heat exchanger C (6), liquid medium B is heated by medium D. The gaseous medium B is compressed by compressor B(5) and then enters heat exchanger B(4), where it is absorbed by the mixture of medium A and medium B and circulates repeatedly. The gaseous medium D is cooled and becomes liquid medium D in heat exchanger C(6) and heat exchanger E(13) in sequence. After passing through throttling device E(19), part of the liquid medium D passes through throttling device C(9) and enters compressor C(8). The remaining liquid medium D enters heat exchanger D(10) and changes from liquid to gas to extract heat from the cold source. The gaseous medium D in heat exchanger D(10) and the gaseous medium D that has passed through throttling device E(19) enter compressor C(8). The medium D in the flow device C(9) is mixed and compressed in the compressor C(8), and gradually becomes liquid medium D in the form of gaseous medium D after passing through heat exchanger C(6) and heat exchanger E(13), releasing heat. Medium E is heated by medium B in heat exchanger F(14) and changes from liquid medium E to gaseous medium E. After being compressed by compressor D(16), gaseous medium E changes from gaseous to liquid in heat exchanger G(17), releasing heat to heat source B. Liquid medium E enters heat exchanger F(14) after passing through throttling device D(15), and the cycle repeats.

2. The 300℃ low-grade heat recovery super heat pump unit and its operation method according to claim 1, characterized in that: The internal circulating medium of this unit consists of medium A, medium B, medium C, medium D, and medium E. Medium A is inorganic salt, ammonia, or Freon; medium B is water, alcohol, or Freon; medium C is a mixture of water and Freon (HD06), ammonia, or carbon dioxide; medium D is water, Freon, ammonia, or carbon dioxide; and medium E is water, Freon, ammonia, or carbon dioxide. The Freon mixture (HD06) consists of three Freon types: R365mfc (2%-85%), R1233zd (1%-95%), and R601 (1%-90%). Medium C circulates between heat exchanger A (1), compressor A (2), throttling device A (3), and heat exchanger B (4). Medium B... The mixture of medium A and medium B circulates in heat exchanger F (14), circulating pump B (18), heat exchanger C (6) and compressor B (5). The mixture of medium A and medium B circulates in heat exchanger B (4), heat exchanger H (12), heat exchanger E (13) and circulating pump A (11). Medium D circulates in compressor C (8), heat exchanger C (6), throttling device B (7), heat exchanger E (13), throttling device E (19) and heat exchanger D (10). Part of medium D after passing through throttling device E (19) enters compressor C (8), and the rest of medium D enters heat exchanger D (10). Medium E circulates in compressor D (16), heat exchanger G (17), throttling device D (15) and heat exchanger F (14).

3. The 300℃ low-grade heat recovery super heat pump unit and its operation method according to claim 1, characterized in that: The cold source is air or industrial waste heat.

4. The 300℃ low-grade heat recovery super heat pump unit and its operation method according to claim 1, characterized in that: The distribution ratio of medium D into throttling device C(9) and heat exchanger D(10) is determined based on the cold source temperature and the outlet temperature and pressure of compressor C(8).

5. The 300℃ low-grade heat recovery super heat pump unit and its operation method according to claim 1, characterized in that: Compressors A(2), B(5), C(8) and D(16) are piston, scroll, centrifugal or screw type, and each compressor uses a single-stage or two-stage compression method.

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