A hot water energy-saving system including a direct-heating thermal energy grade-grading heat exchange module

Abstract

The present invention discloses a hot water energy-saving system including a direct-heating heat energy grade graded heat exchange module. By using a three-stage direct heat exchange method of a sleeve, a temperature-type proportional integral flow distributor reversely adjusts the secondary side water flow rate three times according to the primary side heat energy grade from high to low, and steps are formed to form three-stage zoned water outlets of high temperature, medium temperature and low temperature. The water source in the low temperature zone recovers heat energy to the maximum extent, and users in the medium temperature zone continue to absorb heat on the basis of the low temperature zone, and adopt an auxiliary heating method to obtain user finished water at a low cost, and the high temperature zone directly provides finished hot water for users. The present invention adopts a three-stage cascade heat exchange method and a large temperature difference one-time heat exchange to solve the problems of low-quality high-grade heat, high hot water production and low heat exchange efficiency caused by the traditional circulation heat exchange method, and ensures that users can directly obtain the required hot water in the most economical way, while greatly reducing the heat exchange time and improving the heat exchange efficiency. It can be widely used in the fields of waste heat recovery and hot water energy saving.

Description

Technical Field

[0001] The invention relates to a hot water energy-saving system comprising a direct-heating thermal energy grade-grading heat exchange module, and relates to the technical field of energy recovery and hot water energy saving. Background Art

[0002] At present, many large factories (such as breweries, canned beverage factories, etc.) have a lot of high-temperature waste heat energy wasted on the one hand (such as a large amount of high-temperature wastewater above 85°C in breweries is directly discharged, and the high-temperature water in the sterilization kettle of canned beverage factories is cooled from 120°C to 40°C through the cooling tower cycle, and the heat energy is wasted.) On the other hand, the factories themselves have a large demand for hot water: for example, breweries need hot water above 60°C for bottle washing processes, and canned beverage factories need hot water above 50°C for dissolving beverage solids, etc. At present, heat recovery in the market mostly adopts the circulating heat exchange method. The hot water recovered by this heat exchange method has a single temperature, high-quality heat is low-quality, and high-quality heat energy is wasted. At the same time, the heat exchange time is long and the thermal efficiency is low. Summary of the invention

[0003] The technical problem to be solved by the present invention is to overcome the shortcomings of the above-mentioned prior art and provide a hot water energy-saving system including a direct-heating heat energy grade graded heat exchange module. By using a three-stage direct heat exchange method of a casing, the secondary side water flow rate is reversely adjusted three times from high to low according to the primary side heat energy grade by a temperature-type proportional integral flow distributor, and the high-temperature, medium-temperature and low-temperature three-stage water outlet is formed in stages. The water source in the low-temperature zone recovers heat energy to the maximum extent, and users in the medium-temperature zone continue to absorb heat on the basis of the low-temperature zone, and adopt an auxiliary heating method to obtain user finished water at a low cost. The high-temperature zone directly provides users with free finished hot water.

[0004] The technical solution adopted by the present invention is:

[0005] A hot water energy-saving system including a direct-heating heat energy grade classification heat exchange module includes a primary side casing branch pipe 16, a secondary side casing branch pipe 17, a secondary side high-quality liquid collecting pipe 1, a secondary side medium-quality liquid collecting pipe 2, a secondary side low-quality liquid collecting pipe 3, a temperature sensor Ⅰ5, a proportional integral flow distributor Ⅰ6, a temperature sensor Ⅱ7, and a proportional integral flow distributor Ⅱ8. The hot water energy-saving system is equipped with a low-temperature water tank 10, a medium-temperature water tank 12 or a high-temperature finished water tank 13. The primary side casing branch pipe 16 passes through the inside of the secondary side casing branch pipe 17, and the secondary side casing branch pipe 17 is sealed at the left and right end surfaces of the primary side casing branch pipe 16; the secondary side high-quality liquid collecting pipe 1 is connected with the secondary side casing branch pipe 17 in the first order according to the flow direction of the primary side heat source; the secondary side medium-quality liquid collecting pipe 2 is connected with the secondary side casing branch pipe 17 in the second order according to the flow direction of the primary side heat source; the secondary side low-quality liquid collecting pipe 3 is connected with the secondary side casing branch pipe 17 in the third order according to the flow direction of the primary side heat source; the temperature sensor I5 is connected with the proportional integral flow The proportional integral flow distributor Ⅰ6 is installed on the secondary side high-quality liquid collecting pipe 1, and the temperature sensor Ⅰ5 is installed at the water inlet end of the proportional integral flow distributor Ⅰ6; the temperature sensor Ⅱ7 and the proportional integral flow distributor Ⅱ8 are installed on the secondary side medium-quality liquid collecting pipe 2, and the installation position of the temperature sensor Ⅱ7 is located at the water inlet end of the proportional integral flow distributor Ⅱ8; the low-temperature water tank 10 is connected with the secondary side low-quality liquid collecting pipe 3, and the medium-temperature water tank 12 is connected with the secondary side medium-quality liquid collecting pipe 2; the high-temperature finished water tank 13 is connected with the secondary side high-quality liquid collecting pipe 1.

[0006] The proportional-integral flow distributor I6 is provided with a control signal by the temperature sensor I5.

[0007] The required proportional integral flow distributor Ⅱ8 is provided with a control signal by the temperature sensor Ⅱ7.

[0008] The low temperature water tank 10 provides secondary water source to the secondary casing branch pipe 17 through the secondary hot water distribution pipe 14 via the variable flow water supply pump 11 .

[0009] The primary side heat source enters the primary side casing branch pipe 16 from the primary side heat source water inlet main pipe 19 through the primary side heat source liquid distribution pipe 4, and is collected by the primary side heat source collecting pipe 15 and then discharged from the primary side heat source water outlet main pipe 18.

[0010] The liquid level of the low temperature water tank 10 is automatically controlled by the tap water inlet pipe 23 and the float valve 20. The low temperature water tank 10, the medium temperature water tank 12 and the high temperature finished product water tank 13 are respectively equipped with one temperature sensor 9 each.

[0011] The return water pressure transmitter 22 is installed on the secondary side low-quality liquid collecting pipe 3.

[0012] The auxiliary heating system 21 heats the water source in the medium-temperature water tank 12 to produce finished water which is then sent to the high-temperature finished water tank 13 .

[0013] The beneficial effects of the present invention are as follows: the present invention discloses a hot water energy-saving system including a direct-heating heat energy grade graded heat exchange module. By using a three-stage direct heat exchange method of a sleeve, a temperature-type proportional integral flow distributor reversely adjusts the secondary side water flow rate three times according to the primary side heat energy grade from high to low, and steps are formed to form three-stage zoned water outlets of high temperature, medium temperature and low temperature. The water source in the low temperature zone recovers heat energy to the maximum extent, and users in the medium temperature zone continue to absorb heat on the basis of the low temperature zone, and adopt an auxiliary heating method to obtain user finished water at a low cost, and the high temperature zone directly provides finished hot water to users. The present invention adopts a three-stage cascade heat exchange method and a large temperature difference one-time heat exchange to solve the problems of low-quality high-grade heat, high hot water production and low heat exchange efficiency caused by the traditional circulation heat exchange method, and ensures that users can directly obtain the required hot water in the most economical way, while greatly reducing the heat exchange time and improving the heat exchange efficiency. It can be widely used in the fields of waste heat recovery and hot water energy saving. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the principle of a hot water energy-saving system including a direct-heating thermal energy grade classification heat exchange module according to an embodiment of the present invention;

[0015] Figure 2 It is a partial cross-sectional enlarged schematic diagram of a hot water energy-saving system including a direct-heating thermal energy grade classification heat exchange module according to an embodiment of the present invention;

[0016] In the figure:

[0017] A secondary side high-quality liquid collecting pipe (1), a secondary side medium-quality liquid collecting pipe (2), a secondary side low-quality liquid collecting pipe (3), a primary side heat source liquid distributing pipe (4), a temperature sensor I (5), a proportional integral flow distributor I (6), a temperature sensor II (7), a proportional integral flow distributor II (8), a temperature sensor (9), a low-temperature water tank (10), a variable flow water supply pump (11), a medium-temperature water tank (12), a high-temperature finished water tank (13), a secondary side hot water distribution pipe (14), a primary side heat source liquid collecting pipe (15), a primary side casing branch pipe (16), a secondary side casing branch pipe (17), a primary side heat source water outlet main pipe (18), a primary side heat source water inlet main pipe (19), a float valve (20), an auxiliary heating system (21), a return water pressure transmitter (22), and a tap water inlet pipe (23). DETAILED DESCRIPTION

[0018] like Figures 1-2 As shown, this embodiment includes a hot water energy-saving system of a direct-heating thermal energy grade-grading heat exchange module, which is composed of a direct-heating thermal energy grade-grading heat exchange module and a hot water energy-saving system. The specific implementation method is as follows:

[0019] Primary side heat source working process: The primary side heat source (such as industrial high temperature wastewater) is divided into two routes (Note: multiple routes or single routes are also possible, multiple routes are used when the primary side water flow is large, and single routes are used when the primary side water flow is small) from the primary side heat source liquid distribution pipe 4 into the primary side casing branch pipe 16, and the primary side casing branch pipe 16 is covered with a secondary side casing branch pipe 17, where the heat of the primary and secondary side water sources is fully exchanged, and the primary side water source is collected through the primary side heat source collecting pipe 15 and discharged from the primary side heat source water outlet main pipe 18, and the primary side water source working process is completed. Since the water flowing in the secondary side casing branch pipe 17 that exchanges heat with the primary side is the water source in the low temperature water tank 10 divided by the thermal energy grade, the temperature difference of the primary side water source is large, and the heat energy exchange efficiency is significantly increased;

[0020] The secondary water source workflow is divided into the following three steps:

[0021] First, low-grade heat energy recovery: low-temperature water (water temperature ≥ tap water temperature) in the low-temperature water tank 10 is supplied to the secondary side water source through the secondary side hot water distribution pipe 14 to the secondary side casing branch pipe 17 via the variable flow water supply pump 11, and undergoes the first heat exchange with the primary side heat source embedded in the primary side casing branch pipe 16, and then flows into the low-temperature water tank 10 after being collected through the secondary side low-grade liquid collecting pipe 3. This water tank is the basic heat energy recovery water tank, and its purpose is to recover the low-grade heat energy in the primary side heat source to the greatest extent. The flow rate of the variable flow water supply pump 11 is controlled by the pressure provided by the return water pressure transmitter 22, thereby realizing constant pressure water supply of the secondary side water source, thereby ensuring the stability of heat exchange;

[0022] Second, medium-grade heat recovery: pre-set a medium-grade heat energy limit temperature of T℃,

[0023] T1≤T≤T2, detected by temperature sensor Ⅱ7, the measured signal is sent to proportional integral flow distributor Ⅱ8 to linearly adjust the flow of secondary water source, so as to ensure that the temperature of the recovered medium-grade heat energy is within the temperature range of T1 to T2℃, and then flows into the medium-temperature water tank 12 through the secondary side medium-grade liquid collecting pipe 2. The water tank is a semi-finished water tank. The semi-finished water source is heated into finished water by adding a small amount of heat energy through the auxiliary heating system 21, and then sent to the finished water tank 13, so as to reduce the production cost of directly heating the low-grade heat source into finished water;

[0024] Third, heat energy recovery of high-grade finished hot water: the defined temperature of high-grade finished hot water is pre-set as T>T3℃, which is detected by temperature sensor Ⅰ5, and the measured signal is sent to proportional integral flow distributor Ⅰ6 for flow regulation of secondary water source to ensure that the temperature of high-grade finished hot water is greater than T3℃. After passing through the secondary high-grade liquid collecting pipe 1, it flows into the high-temperature finished water tank 13. This water tank is a finished water tank, and the internal water source does not need any heating and is directly used by users, thereby providing users with finished hot water free of charge, with obvious energy-saving effect.

[0025] Through the above specific implementation, the present invention forms three-stage water output of high temperature, medium temperature and low temperature. The water source in the low temperature zone recovers heat energy to the maximum extent, the users in the medium temperature zone continue to absorb heat on the basis of the low temperature zone, and adopts auxiliary heating method to obtain user finished water at low cost, and the high temperature zone directly provides finished hot water for users free of charge.

[0026] The present invention adopts a three-stage cascade heat exchange method and a large temperature difference one-time heat exchange, which solves the problems of low-quality high-grade heat, high hot water production and low heat exchange efficiency caused by the traditional circulation heat exchange method, and ensures that users can directly obtain the required hot water in the most economical way. At the same time, it greatly reduces the heat exchange time and improves the heat exchange efficiency. It can be widely used in the fields of waste heat recovery and hot water energy saving.

[0027] The above description is not a limitation of the present invention, and the present invention is not limited to the above-mentioned embodiments. As long as the changes, modifications, additions or substitutions are made within the essential scope of the present invention, so as to achieve the technical effects of the present invention, they should fall within the protection scope of the present invention.

Claims

1. A hot water energy saving system comprising a direct-heating heat energy grade classification heat exchange module, characterized in that: The direct-heating heat energy grade classification heat exchange module comprises a primary side casing branch pipe (16), a secondary side casing branch pipe (17), a secondary side high-quality liquid collecting pipe (1), a secondary side medium-quality liquid collecting pipe (2), A secondary side low-quality liquid collecting pipe (3), a temperature sensor I (5), a proportional integral flow distributor I (6), a temperature sensor II (7), a proportional integral flow distributor II (8), a low-temperature water tank (10), a medium-temperature water tank (12), and a high-temperature finished water tank (13); the primary side casing branch pipe (16) passes through the interior of the secondary side casing branch pipe (17), and the secondary side casing branch pipe (17) is sealed at both left and right end surfaces where the primary side casing branch pipe (16) passes through; the secondary side high-quality liquid collecting pipe (1) and the secondary side casing branch pipe (17) are connected in a first order according to the flow direction of the primary side heat source; the secondary side medium-quality liquid collecting pipe (2) and the secondary side casing branch pipe (17) are connected in a second order according to the flow direction of the primary side heat source; the secondary side low-quality liquid collecting pipe (3) and the secondary side casing branch pipe ( 17) A third sequence of through-connections is performed according to the flow direction of the primary side heat source; the temperature sensor I (5) and the proportional integral flow distributor I (6) are both installed on the secondary side high-quality liquid collecting pipe (1), and the temperature sensor I (5) is installed at the water inlet end of the proportional integral flow distributor I (6); the temperature sensor II (7) and the proportional integral flow distributor II (8) are both installed on the secondary side medium-quality liquid collecting pipe (2), and the installation position of the temperature sensor II (7) is located at the water inlet end of the proportional integral flow distributor II (8); the low-temperature water tank (10) is connected to the secondary side low-quality liquid collecting pipe (3), and the medium-temperature water tank (12) is connected to the secondary side medium-quality liquid collecting pipe (2); the high-temperature finished water tank (13) is connected to the secondary side high-quality liquid collecting pipe (1).

2. A hot water energy-saving system comprising a direct-heating heat energy grade-grading heat exchange module according to claim 1, characterized in that: The proportional integral flow distributor I (6) is provided with a control signal by the temperature sensor I (5).

3. A hot water energy-saving system comprising a direct-heating heat energy grade-grading heat exchange module according to claim 1, characterized in that: The proportional integral flow distributor II (8) is provided with a control signal by the temperature sensor II (7).

4. A hot water energy-saving system comprising a direct-heating heat energy grade-grading heat exchange module according to claim 1, characterized in that: The low-temperature water tank (10) provides a secondary water source to the secondary casing branch pipe (17) via a variable flow water supply pump (11) and a secondary hot water distribution pipe (14).

5. A hot water energy-saving system comprising a direct-heating heat energy grade-grading heat exchange module according to claim 1, characterized in that: The primary side heat source enters the primary side casing branch pipe (16) from the primary side heat source water inlet main pipe (19) through the primary side heat source liquid distribution pipe (4), is collected through the primary side heat source liquid collecting pipe (15), and is discharged from the primary side heat source water outlet main pipe (18).

6. A hot water energy-saving system comprising a direct-heating heat energy grade-grading heat exchange module according to claim 1, characterized in that: The liquid level of the low-temperature water tank (10) is automatically controlled by a tap water inlet pipe (23) and a float valve (20). The low-temperature water tank (10), the medium-temperature water tank (12) and the high-temperature finished product water tank (13) are each equipped with a temperature sensor (9).

7. A hot water energy-saving system comprising a direct-heating heat energy grade-grading heat exchange module according to claim 1, characterized in that: It also includes a return water pressure transmitter (22), which is installed on the secondary side low-quality liquid collecting pipe (3).

8. A hot water energy-saving system comprising a direct-heating heat energy grade-grading heat exchange module according to claim 1, characterized in that: It also includes an auxiliary heating system (21), which heats the water source in the medium-temperature water tank (12) to produce finished water and feeds it into the high-temperature finished water tank (13).

Images