Central kitchen steam supply device

Abstract

A central kitchen steam supply device comprises a cabinet body, an evaporation cylinder and a heat exchange cylinder are arranged in the cabinet body, an upper partition plate and a lower partition plate are arranged in the heat exchange cylinder, the upper partition plate and the lower partition plate divide an inner cavity of the heat exchange cylinder into a steam cavity, a heat exchange cavity and a water return cavity from top to bottom, and the top of the evaporation cylinder is communicated with the steam cavity through a steam recovery pipe. A first control valve is arranged on the steam recovery pipe, a steam flow pipe is connected between the upper partition plate and the lower partition plate, and the steam flow pipe is communicated with the steam cavity and the water return cavity; the heat exchange cavity is connected with a first water inlet pipe and communicates with the evaporation barrel through a second water inlet pipe, and a second control valve is arranged on the second water inlet pipe; the water return cavity communicates with the outside of the heat exchange cylinder through a constant-pressure pipe, and the heat exchange cavity communicates with the constant-pressure pipe through a constant-pressure branch pipe. The heat exchange cylinder is additionally arranged beside the evaporation cylinder, heat exchange is carried out between surplus steam internal energy generated by the evaporation cylinder and inlet water through the heat exchange cylinder, it is guaranteed that steam supply is sufficient, meanwhile, the surplus steam internal energy can be recycled, the inlet water is preheated, and energy consumption of the evaporation cylinder is reduced.

Description

Technical Field

[0001] The present invention relates to the field of steam supply, and particularly to a steam supply device for a central kitchen. Background Art

[0002] The steam supply device for a central kitchen is an important facility for efficient production in fields such as catering and food processing. Its core principle is to convert water into steam through a boiler or a steam generator, and then transport the steam to each use terminal (such as a steam cabinet, a disinfection device, a heating device, etc.) through a pipeline system.

[0003] The production in a central kitchen may have peaks and valleys, and the demand in the catering industry is high during the dining hours and low during other periods. Currently, the steam supply device for a central kitchen is overdesigned, with a rated production capacity higher than the actual average demand, leaving a certain margin (usually 20% - 30%). However, when overdesigned, energy will be wasted during off-peak hours.

[0004] Therefore, the present invention provides a steam supply device for a central kitchen, which can meet the steam demand during peaks through overdesign, and recover the energy of the surplus steam during other periods. Summary of the Invention

[0005] According to the problems raised in the background art, the present invention provides a steam supply device for a central kitchen to solve them, and the following is a further elaboration of the present invention.

[0006] The steam supply device for a central kitchen includes a cabinet body. An evaporation cylinder is arranged inside the cabinet body, a heating element is arranged inside the evaporation cylinder, and a steam outlet pipe is connected to the top. A heat exchange cylinder is arranged inside the cabinet body. An upper partition plate and a lower partition plate are arranged inside the heat exchange cylinder. The upper partition plate and the lower partition plate divide the inner cavity of the heat exchange cylinder into a steam cavity, a heat exchange cavity, and a return water cavity from top to bottom. The top of the evaporation cylinder is connected to the steam cavity through a steam recovery pipe. A first control valve is arranged on the steam recovery pipe. A steam flow pipe is connected between the upper partition plate and the lower partition plate, and the steam flow pipe is communicated with the steam cavity and the return water cavity. The heat exchange cavity is connected to a first water inlet pipe, and the heat exchange cavity is communicated with the evaporation cylinder through a second water inlet pipe. A second control valve is arranged on the second water inlet pipe. The return water cavity is communicated to the outside of the heat exchange cylinder through a constant pressure pipe, and the heat exchange cavity is communicated with the constant pressure pipe through a constant pressure branch pipe.

[0007] Preferably, a first liquid level gauge and a pressure gauge are further arranged on the evaporation cylinder, which are respectively used to limit the height of the water level and the pressure inside the evaporation cylinder.

[0008] Preferably, the steam flow pipe is arranged in a spiral form in the heat exchange cavity and the number is more than one, aiming to increase the steam flow rate and the heat exchange area with the incoming water.

[0009] Preferably, a Venturi tube is connected to the first water inlet pipe. The return water chamber is connected to the throat section of the Venturi tube through a return water pipe, and a third control valve is provided on the return water pipe. A second liquid level gauge for displaying the liquid level in the return water chamber is provided outside the heat exchange cylinder. On the one hand, it aims to recycle the water in the return water chamber and connect it with the inlet water to flow back to the heat exchange chamber together, and on the other hand, to maintain the constant pressure in the return water chamber.

[0010] Preferably, it further includes a pressure control mechanism. The pressure control mechanism includes an air extraction cylinder. The inside of the air extraction cylinder is a cavity, and the cavity is connected to the evaporation cylinder through an air duct. A piston is placed in the cavity. The top of the air extraction cylinder is connected to a hydraulic cylinder, and the output of the hydraulic cylinder is connected to the piston. It aims to enable the evaporation cylinder to operate under high pressure during the initial startup stage and quickly generate steam.

[0011] Preferably, a pre-storage cylinder is connected below the air extraction cylinder. The top of the pre-storage cylinder is connected to the air extraction cylinder, the air duct is connected to the pre-storage cylinder, and a drain valve is provided at the top of the pre-storage cylinder. The separation of air flow and water body is realized in the pre-storage cylinder, and the drain valve is regularly opened to drain the accumulated water in the pre-storage cylinder.

[0012] Preferably, a separation cover is detachably connected to the bottom of the evaporation cylinder. The heating element is placed inside the separation cover, and the heating element is in direct contact with the separation cover. The separation cover is made of a good heat conductor. On the one hand, the separation cover increases the contact area with the water body, and on the other hand, it isolates and protects the heating element.

[0013] Preferably, a steam-water separator is connected to the top of the evaporation cylinder. It aims to separate the water droplets in the steam and then transport it to the application terminal.

[0014] Beneficial effects: Compared with the prior art, the present invention adds a heat exchange cylinder beside the evaporation cylinder. Through the heat exchange cylinder, the internal energy of the surplus steam generated by the evaporation cylinder is heat-exchanged with the inlet water. While ensuring sufficient steam supply, it can recover the internal energy of the surplus steam and preheat the inlet water, reducing the energy consumption of the evaporation cylinder; through the provided return water pipe, on the one hand, it recovers the water in the return water chamber and connects it with the inlet water to flow back to the heat exchange chamber together, and on the other hand, it maintains the constant pressure in the return water chamber; by setting the pressure control mechanism, the steam supply device is in a high-pressure operation state during the initial startup stage, and steam can be quickly generated; also, through the separation cover, while increasing the contact area with the water body, it isolates and protects the heating element. Description of the Drawings

[0015] Figure 1 : Structural schematic diagram of the steam supply device for the central kitchen of the present invention;

[0016] Figure 2 : Connection structural schematic diagram of the evaporation cylinder and the heat exchange cylinder in the cabinet;

[0017] Figure 3 : Internal structural schematic diagram of the evaporation cylinder and the heat exchange cylinder;

[0018] In the figure: cabinet body 1, evaporation cylinder 2, heat exchange cylinder 3, steam chamber 301, heat exchange chamber 302, return water chamber 303, heating element 4, steam delivery pipe 5, steam recovery pipe 6, first control valve 7, steam flow pipe 8, first water inlet pipe 9, second water inlet pipe 10, second control valve 11, constant pressure pipe 12, constant pressure branch pipe 13, first liquid level gauge 14, pressure gauge 15, Venturi tube 16, return water pipe 17, third control valve 18, air extraction cylinder 19, air duct 20, piston 21, hydraulic cylinder 22, pre-storage cylinder 23, drain valve 24, isolation cover 25, steam-water separator 26, upper partition plate 27, lower partition plate 28. Specific embodiments

[0019] Next, in combination with the attached Figures 1-3 A specific embodiment of the present invention will be elaborated in detail.

[0020] Refer to the attached Figures 1-2 , the central kitchen steam supply device, including a cabinet body 1, the cabinet body 1 is internally provided with an evaporation cylinder 2 and a heat exchange cylinder 3, the evaporation cylinder 2, the evaporation cylinder 2 is internally provided with a heating element 4, the heating element 4 generates heat after being powered on, heats the water body in the evaporation cylinder 2 to volatilize it into steam, the top of the evaporation cylinder 2 is connected with a steam delivery pipe 5, and the steam generated in the evaporation cylinder 2 is transported to each use terminal through the steam delivery pipe 5.

[0021] As described in the background art, the central kitchen steam supply device of the present invention adopts an excessive design. Especially when working during off-peak hours, in order to recover the excess steam energy, in this embodiment, the surplus steam is exchanged heat with the incoming water to be evaporated entering the evaporation cylinder 2, transferring the internal energy of the surplus steam to the internal energy of the incoming water, increasing the temperature of the incoming water, and reducing the energy consumption of the evaporation cylinder 2.

[0022] Refer to the attached Figures 1-3, a upper partition plate 27 and a lower partition plate 28 are arranged inside the heat exchange cylinder 3. The upper partition plate 27 and the lower partition plate 28 divide the inner cavity of the heat exchange cylinder 3 into a steam cavity 301, a heat exchange cavity 302 and a return water cavity 303 from top to bottom. The top of the evaporation cylinder 2 is connected to the steam cavity 301 through a steam recovery pipe 6. A first control valve 7 is arranged on the steam recovery pipe 6 to control the on-off of the steam recovery pipe 6. A steam flow pipe 8 is connected between the upper partition plate 27 and the lower partition plate 28. The steam flow pipe 8 is communicated with the steam cavity 301 and the return water cavity 303. The steam in the steam cavity 301 will enter the steam flow pipe 8 under pressure. The heat exchange cavity 302 is connected to a first water inlet pipe 9. Tap water enters the heat exchange cavity 302 through the first water inlet pipe 9. There is a certain liquid level in the heat exchange cavity 302, submerging the steam flow pipe 8. The incoming water exchanges heat with the steam in the steam flow pipe 8. The heat exchange cavity 302 is communicated with the inner cavity of the evaporation cylinder 2 through a second water inlet pipe 10. A second control valve 11 is arranged on the second water inlet pipe 10. The incoming water after heat exchange and temperature rise enters the evaporation cylinder 2. The return water cavity 303 is communicated to the outside of the heat exchange cylinder 3 through a constant pressure pipe 12. The heat exchange cavity 302 is communicated with the constant pressure pipe 12 through a constant pressure branch pipe 13 to maintain the constant pressure in the return water cavity 303 and the heat exchange cavity 302.

[0023] A first liquid level gauge 14 and a pressure gauge 15 are also arranged on the evaporation cylinder 2, which are respectively used to limit the height of the water level in the evaporation cylinder 2 and the pressure in the evaporation cylinder 2.

[0024] The working principle of the heat exchange cylinder 3 is as follows: In the initial start-up stage, the first control valve 7 is closed and the second control valve 11 is opened. The flowing water first enters the heat exchange cavity 302 from the first water inlet pipe 9. The heat exchange cavity 302 and the inner cavity of the evaporation cylinder 2 form a communicating vessel. As the liquid level in the heat exchange cavity 302 gradually rises, the gas in the heat exchange cavity 302 is discharged outside the heat exchange cylinder 3 until the incoming water begins to enter the evaporation cylinder 2. When the first liquid level gauge 14 shows that the liquid level in the evaporation cylinder 2 reaches the target height, the filling stops; then, the second control valve 11 is closed, and the heating element 4 is energized to generate heat, heating the water body in the evaporation cylinder 2 to the target temperature to generate steam. Observe the pressure gauge 15. After reaching the target evaporation amount, open and send the steam to each use terminal through the steam delivery pipe 5. At this time, open the first control valve 7. The surplus steam enters the steam cavity 301 of the heat exchange cylinder 3 through the steam recovery pipe 6 and enters the steam flow pipe 8 under thermal pressure, and exchanges heat with the incoming water submerging the outer wall in the steam flow pipe 8. After the steam is cooled, it liquefies and undergoes a phase change into liquid water, gradually converging downward at the bottom return water cavity 303; during the working process, as the steam is continuously output, the water body in the evaporation cylinder 2 is gradually consumed. To maintain the working liquid level, the incoming water after heat exchange and temperature rise in the heat exchange cavity 302 gradually enters the evaporation cylinder 2 through the second water inlet pipe 10 to make up for the consumption of the water body.

[0025] The number of the steam flow pipes 8 is more than one, and they are arranged in a spiral form in the heat exchange cavity 302, aiming to increase the steam flow rate and the heat exchange area with the incoming water.

[0026] After the steam exchanges heat in the steam flow pipes 8, it liquefies and converges at the bottom return water cavity 303. On the one hand, the water temperature in the return water cavity 303 is also significantly higher than the incoming water and is also worthy of being recycled. On the other hand, the liquid level height of the water body in the return water cavity 303 gradually increases. When the return water cavity 303 is filled, it will occupy the space of the steam flow pipes 8 and form a liquid seal at the bottom of the constant pressure pipe 12, and the pressure in the steam flow pipes rises, all of which will affect the heat exchange efficiency. In this embodiment, the liquefied water body is recycled as the incoming water and returned to the heat exchange cavity 302 to achieve the dual purposes of fully recovering energy and maintaining the constant pressure in the return water cavity 303.

[0027] Reference appendix Figures 2-3 , specifically, a Venturi tube 16 is connected to the first incoming water pipe 9, and the return water cavity 303 is connected to the throat section of the Venturi tube 16 through a return water pipe 17. A third control valve 18 is provided on the return water pipe 17, and a second liquid level gauge (not shown) for displaying the liquid level height of the return water cavity 303 is provided outside the heat exchange cylinder 3.

[0028] When the liquid level gauge of the heating element 4 shows that the liquid level height of the return water cavity 303 reaches the target height, the third control valve 18 is opened. Since the first incoming water pipe 9 continuously supplies water to the heat exchange cavity 302 during the working process, the Venturi tube is a pipe designed based on the principle of fluid dynamics. By changing the cross-sectional area of the pipe, the conversion of fluid flow velocity and pressure is realized. The flow velocity is the largest and the pressure is the lowest at the throat section of the Venturi tube. The return water pipe 17 is connected to the throat section of the Venturi tube 16, and the pressure difference causes the water body in the return water cavity 303 to be sucked into the Venturi tube and merged with the incoming water and then pumped into the heat exchange cavity 302.

[0029] Reference appendix Figures 2-3 , in the initial startup stage of the steam supply device, high-pressure operation is generally preferred to quickly generate steam. In this embodiment, a pressure control mechanism is provided to regulate the pressure in the evaporation cylinder 2. In the initial startup stage, the evaporation cylinder 2 is controlled to be at high pressure. The pressure control mechanism includes an air extraction cylinder 19. The inside of the air extraction cylinder 19 is a cavity, and the cavity is connected to the evaporation cylinder 2 through an air passage 20. A piston 21 is arranged in the cavity. The top of the air extraction cylinder 19 is connected to a hydraulic cylinder 22, and the output of the hydraulic cylinder 22 is connected to the piston 21.

[0030] In the initial startup stage, the external valve of the evaporation cylinder 2 is closed, the hydraulic cylinder 22 acts, pulling the piston 21 to move downward in the cavity of the air extraction cylinder 19, and compressing the gas in the cavity of the air extraction cylinder 19 into the evaporation cylinder. The pressure in the evaporation cylinder rises. By observing the pressure gauge 15, the pressure in the evaporation cylinder is controlled at the target pressure. Then the heating element 4 is started, and steam can be quickly generated.

[0031] The position where the air duct 20 communicates with the evaporation cylinder 2 is at a high level, above the height of the working liquid, to prevent water from being pumped into the air extraction cylinder 19. However, the steam will also liquefy on the inner wall of the air duct 20 and flow downward. In this embodiment, the liquefied water body is pre-stored to isolate it from entering the air extraction cylinder: a pre-storage cylinder 23 is connected below the air extraction cylinder 19. The top of the pre-storage cylinder 23 communicates with the air extraction cylinder 19. The air duct 20 communicates with the pre-storage cylinder 23, and a drain valve 24 is provided at the top of the pre-storage cylinder 23. After the steam liquefies upon contact with the inner wall of the air duct 20, it flows downward and converges in the pre-storage cylinder 23, where the separation of the air flow and the water body is achieved. The drain valve 24 is periodically opened to drain the accumulated water in the pre-storage cylinder 23.

[0032] Reference appendix Figures 2-3 , during the long-term operation of the steam supply device, the accumulation of scale is inevitable. The scale mainly adheres to high-temperature areas such as the inner wall of the boiler and the heating element. The scale covers the heat-absorbing surface of the boiler, hindering heat transfer and resulting in an increase in energy consumption. In this embodiment, the heating element is isolated and protected: the bottom of the evaporation cylinder 2 is detachably connected with an isolation cover 25. The heating element 4 is placed inside the isolation cover 25, and moreover, the heating element 4 is in direct contact with the isolation cover 25. The isolation cover 25 is made of a good thermal conductor. On the one hand, the isolation cover 25 increases the contact area with the water body and shortens the evaporation time. On the other hand, it isolates and protects the heating element 4. The scale adheres to the isolation cover and can be periodically disassembled, cleaned, or replaced.

[0033] Reference appendix Figure 2 , different application scenarios of steam have different effects on the steam dryness of the steam. The steam dryness refers to the mass ratio of the dry gas in the steam. For food processing that is sensitive to steam quality, dehumidification operations are required, and the steam dryness needs to be stabilized at 95% - 99%. Based on this, in this embodiment, a steam-water separator 26 is connected to the top of the evaporation cylinder 2 to separate the water droplets in the steam and then transport it to the application terminal.

[0034] The present invention adds a heat exchange cylinder beside the evaporation cylinder. Through the heat exchange cylinder, the internal energy of the surplus steam generated by the evaporation cylinder is heat-exchanged with the incoming water. While ensuring sufficient steam supply, the internal energy of the surplus steam can be recovered, the incoming water is preheated, and the energy consumption of the evaporation cylinder is reduced; through the set return water pipe, on the one hand, the water body in the return water cavity is recovered and flows back to the heat exchange cavity together with the incoming water, and on the other hand, the pressure in the return water cavity is maintained constant; then, by setting a pressure control mechanism, the steam supply device operates at a high pressure during the initial startup stage, and steam can be quickly generated; also, the isolation cover increases the contact area with the water body and at the same time isolates and protects the heating element.

[0035] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A central kitchen steam supply device, comprising a cabinet (1), wherein the cabinet (1) has an evaporating cylinder (2) built in, wherein the evaporating cylinder (2) has a heating element (4) built in, and a steam delivery pipe (5) connected to the top; the device is characterized by: The cabinet (1) has a heat exchange cylinder (3) built therein, and the heat exchange cylinder (3) has an upper partition (27) and a lower partition (28) built therein, and the upper partition (27) and the lower partition (28) divide the inner cavity of the heat exchange cylinder (3) into a steam cavity (301), a heat exchange cavity (302) and a water return cavity (303) from top to bottom, and the top of the evaporation cylinder (2) is connected to the steam cavity (301) through a steam recovery pipe (6), and a first control valve (7) is arranged on the steam recovery pipe (6). The upper partition (27) and the lower partition (28) are connected to each other. A steam flow pipe (8) is connected, and the steam flow pipe (8) is connected to the steam chamber (301) and the return water chamber (303); the heat exchange chamber (302) is connected to the first water inlet pipe (9), and the heat exchange chamber (302) is connected to the evaporation cylinder (2) through the second water inlet pipe (10), and the second water inlet pipe (10) is provided with a second control valve (11); the return water chamber (303) is connected to the outside of the heat exchange cylinder (3) through the constant pressure pipe (12), and the heat exchange chamber (302) is connected to the constant pressure pipe (12) through the constant pressure branch pipe (13).

2. The central kitchen steam supply device according to claim 1, characterized in that: The evaporating cylinder (2) is also provided with a first liquid level gauge (14) and a pressure gauge (15).

3. The central kitchen steam supply device according to claim 1, characterized in that: The steam flow pipe (8) is arranged in a spiral form in the heat exchange chamber (302), and the number of the steam flow pipes is more than one.

4. The central kitchen steam supply device according to claim 1, characterized in that: The first water inlet pipe (9) is connected to a Venturi tube (16), the return water chamber (303) is connected to the throat section of the Venturi tube (16) via a return water pipe (17), a third control valve (18) is provided on the return water pipe (17), and a second liquid level meter for displaying the liquid height of the return water chamber (303) is provided outside the heat exchange tube (3).

5. The central kitchen steam supply device according to claim 4, characterized in that: The invention also comprises a pressure control mechanism, which comprises a vacuum cylinder (19), the interior of the vacuum cylinder (19) is a cavity, the cavity is connected to the evaporation cylinder (2) through an air passage (20), a piston (21) is built in the cavity, the top end of the vacuum cylinder (19) is connected to a hydraulic cylinder (22), and the output of the hydraulic cylinder (22) is connected to the piston (21).

6. The central kitchen steam supply device according to claim 5, characterized in that: A pre-storage cylinder (23) is connected below the air extraction cylinder (19), the top of the pre-storage cylinder (23) is in communication with the air extraction cylinder (19), the air passage (20) is in communication with the pre-storage cylinder (23), and a drainage valve (24) is provided at the top of the pre-storage cylinder (23).

7. The central kitchen steam supply device according to claim 6, characterized in that: The bottom of the evaporating cylinder (2) is connected to an isolation cover (25), the heating element (4) is built into the isolation cover (25), the heating element (4) is in direct contact with the isolation cover (25), and the isolation cover (25) is a good thermal conductor.

8. The central kitchen steam supply device according to claim 1, characterized in that: The top of the evaporation cylinder (2) is connected to a steam-water separator (26).

Images