Forced circulation evaporator with built-in heat exchange

Abstract

The application belongs to the technical field of heat exchanger of chemical equipment, and particularly discloses a forced circulation evaporator with built-in heat exchange, which comprises a heat exchange device, a heating device and an evaporator shell, wherein the heat exchange device is provided with a steam inlet and a condensate outlet; the heating device is arranged outside the heat exchange device and comprises a heater and a feeding cavity; the bottom side of the feeding cavity is provided with an opening and is in gap cooperation with the heater, so that the raw material flows down along the outer sidewall of the heater after passing through the feeding cavity; the evaporator shell is used for containing the heat exchange device and the heating device; an upper cavity is arranged on the heat exchange device and is in communication with the heat exchange device; and the forced circulation device comprises a circulating pump arranged at the bottom of the inner side of the evaporator shell and a circulating pipe, and the circulating pump is in communication with the inside of the heat exchange device through the circulating pipe and is connected to the upper cavity. The heat exchange device is reasonably arranged on the inner side of the evaporator, so that the occupied space is reduced, the heat preservation and insulation are better, and the utilization rate is effectively improved.

Description

Technical Field

[0001] This invention belongs to the technical field of heat exchangers for chemical equipment, and specifically relates to a forced circulation evaporator with internal heat exchange. Background Technology

[0002] Heat exchange refers to the transfer of heat between two fluids, and is a unit operation within the heat transfer process. Heat exchange operations are widely used in various engineering fields, and are particularly closely related to the chemical industry. The purpose of heat exchange is to heat, cool, vaporize, or condense materials to achieve or maintain the temperature or phase required by the production process. In chemical production, heat exchange occurs between two fluid materials, or between a fluid material and a heat carrier. Heat exchange between two fluids typically takes place in a heat exchanger. The contact heat transfer methods of heat exchangers include indirect-contact, direct-contact, and regenerative types, with indirect-contact heat exchangers being the most widely used. In the comprehensive utilization of heat, the hot fluid to be cooled is used to supply heat to the cold fluid to be heated, thereby improving heat utilization efficiency.

[0003] In existing forced circulation evaporators, the heat exchanger and separator are arranged separately and connected by external pipelines. The heater shell of the heat exchanger has an ineffective heat exchange interface and a small size, which affects the efficiency of the equipment. In addition, the equipment has a long pipeline, poor insulation, large footprint, and high investment. Summary of the Invention

[0004] To address the problems of low evaporator efficiency, poor insulation, and large space occupation in existing technologies, a forced circulation evaporator with internal heat exchange is proposed. This invention provides the following technical solution:

[0005] A forced circulation evaporator with internal heat exchange, comprising:

[0006] A heat exchange device, which is equipped with a steam inlet and a condensate outlet;

[0007] The heating device is located outside the heat exchange device and includes a heater and a feeding chamber. The bottom side of the feeding chamber has an opening that is clearance-fitted with the heater, so that the raw material flows down along the outer wall of the heater after passing through the feeding chamber.

[0008] Evaporator shell, used in volumetric heat exchange devices and heating devices;

[0009] The upper cavity is covered on the heat exchange device and connected to the heat exchange device;

[0010] The forced circulation device includes a circulation pump and a circulation pipe located at the bottom inside the evaporator shell. The circulation pump is connected to the inside of the heat exchange device and leads to the upper cavity through the circulation pipe.

[0011] Preferably, the heat exchange device includes a central heat exchange tube and an outer peripheral heat exchange tube, both of which are connected to the upper cavity. The circulating material pipe is connected to the central heat exchange tube, and the outer peripheral heat exchange tube is provided with a drain port for cooperating with the circulating pump to realize the circulation of raw materials.

[0012] Preferably, a support pipe is provided between the bottom side of the heat exchange device and the outer shell of the evaporator.

[0013] Preferably, a swirl plate is provided on the outer ring of the support tube.

[0014] Preferably, a pump feed inlet is provided at the bottom of the evaporator shell, and a circulating pump is connected to the outside of the pump feed inlet.

[0015] Preferably, an exhaust port is provided on the upper part of the evaporator casing.

[0016] Preferably, a separator for gas-liquid separation is provided on the lower side of the exhaust port.

[0017] Preferably, an operation hole is provided in the middle of the outer shell side of the evaporator.

[0018] Preferably, the upper side of the evaporator shell is provided with an installation port, the feed chamber is snapped into the installation port, and the upper side of the feed chamber is provided with a feed chamber fixing flange and a heat exchange fixing flange in sequence. The feed chamber fixing flange is connected to the feed chamber, and the heat exchange fixing flange is connected to the heat exchange device.

[0019] Preferably, an upper tube sheet is provided at the upper end of the heat exchange device, and an upper cavity flange is connected to the upper cavity body, with the upper cavity flange and the upper tube sheet being connected in a mating manner.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] This invention reduces the space occupied by rationally placing the heat exchange device inside the evaporator, while providing better heat insulation and effectively improving utilization. Simultaneously, the annular, bottom-opening feed chamber allows the liquid to flow more evenly onto the outer wall of the heater, ensuring thorough heating. Furthermore, the heater is cleverly integrated into the heat exchanger, resulting in a compact and ingenious structure with high utilization. Some unvaporized liquid can be forcibly pumped back to the heat exchanger by the circulating pump below, ultimately improving vaporization efficiency. Operation and vent ports are also provided to enhance maintainability and service life. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of the present invention;

[0023] In the attached diagram: 1. Evaporator shell; 11. Operating port; 12. Exhaust port; 21. Outer heat exchange tube; 22. Central heat exchange tube; 23. Steam inlet; 24. Condensate outlet; 25. Heat exchange fixed flange; 26. Upper tube sheet; 27. Lower tube sheet; 31. Feed inlet; 32. Feed chamber; 33. Conical narrow-gap liquid distribution ring; 34. Heater; 35. Feed chamber fixed flange; 4. Upper chamber; 41. Upper chamber flange; 51. Circulating pump; 52. Circulating feed pipe; 53. Pump feed inlet; 54. Discharge port; 6. Support pipe; 7. Swirl plate; 8. Separator. Detailed Implementation

[0024] To enable those skilled in the art to better understand the technical solution of the present invention, the technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings. The directional terms mentioned in the following embodiments, such as "up", "down", "left", "right", etc., are only for reference to the directions in the accompanying drawings. Therefore, the directional terms used are for illustration and not for limiting the invention.

[0025] like Figure 1 As shown, a forced circulation evaporator with internal heat exchange includes:

[0026] The heat exchange device is equipped with a steam inlet 23 and a condensate outlet 24.

[0027] The heating device, located outside the heat exchange device, includes a heater 34 and a feed chamber 32. The feed chamber 32 is provided with a feed inlet 31, and an opening is provided on the bottom side of the feed chamber 32, which is in clearance fit with the heater 34, so that the raw material flows down along the outer wall of the heater 34 after passing through the feed chamber 32. Specifically, a conical narrow-gap liquid distribution ring 33 is arranged at the opening on the bottom side of the feed chamber 32, and the heater 34 is also cylindrical, which can increase the contact area between the liquid and the heater 34.

[0028] Evaporator shell 1, used for volumetric heat exchange device and heating device;

[0029] Upper cavity 4 is covered on the heat exchange device and connected to the heat exchange device;

[0030] The forced circulation device includes a circulation pump 51 and a circulation pipe 52 located at the bottom inside the evaporator shell 1. The circulation pump 51 is connected to the inside of the heat exchange device and to the upper cavity 4 through the circulation pipe 52.

[0031] This invention reduces the space occupied by rationally arranging the heat exchange device inside the evaporator, while providing better heat insulation and effectively improving utilization.

[0032] Furthermore, the heat exchange device includes a central heat exchange tube 22 and an outer peripheral heat exchange tube 21, both of which are connected to the upper cavity 4. The circulating material pipe 52 is connected to the central heat exchange tube 22, and the outer peripheral heat exchange tube 21 is provided with a drain port for cooperating with the circulating pump 51 to realize the circulation of raw materials. A discharge port 54 is also connected to one side of the circulating material pipe 52. Under the action of the circulating pump 51, most of the liquid will flow to the heat exchange device and then flow down through the drain port to realize circulation. A small portion of the liquid will be discharged through the discharge port 54. For precise control, a valve and a flow valve can be installed at the discharge port 54.

[0033] Furthermore, a support pipe 6 is provided between the bottom of the heat exchange device and the evaporator shell 1; a swirl plate 7 is provided around the outer ring of the support pipe 6 to reduce the circulation loss of the circulating pump 51 and promote circulation; a pump feed inlet 53 is provided at the bottom of the evaporator shell 1, and the outside of the pump feed inlet 53 is connected to the circulating pump 51, which is close to the swirl plate 7 to facilitate the swirl plate 7 to swirl some liquid into the circulating pump 51. An exhaust port 12 is provided at the top of the evaporator shell 1; a separator 8 for gas-liquid separation is provided below the exhaust port 12. The separator 8 adopts a multi-layer graded structure to improve the gas-liquid separation effect. An operation hole 11 is provided in the middle of the side of the evaporator shell 1 for easy inspection and maintenance. An installation port is provided on the upper side of the evaporator shell 1, and the feed chamber 32 is snapped into the installation port. A feed chamber fixing flange 35 and a heat exchange fixing flange 25 are sequentially provided on the upper side of the feed chamber 32. The feed chamber fixing flange 35 is connected to the top of the feed chamber 32, and the heat exchange fixing flange 25 is connected to the heat exchange device to achieve a tight connection between the feed chamber 32 and the heat exchange device.

[0034] Furthermore, an upper tube sheet 26 is provided at the upper end of the heat exchange device, and an upper cavity flange 41 is connected to the upper cavity 4. The upper cavity flange 41 and the upper tube sheet 26 are connected to each other to achieve a tight connection between the upper cavity 4 and the heat exchange device. The bottom side of the heat exchange device is connected to the support pipe 6 through the lower tube sheet 27. The lower tube sheet 27 and the upper tube sheet 26 fix the entire heat exchange device to make it firmly connected.

[0035] Work process:

[0036] Steam enters the heat exchanger shell through the upper steam inlet 23, exchanges heat with the material through the outer peripheral heat exchange tube 21 and the outer shell of the heater 34, and condenses into water and is discharged through the condensate outlet 24. The material solution to be treated enters the feed chamber 32 through the feed inlet 31, and flows evenly down the outer shell of the heater 34 through the gap between the conical narrow-gap liquid distribution ring 33 and the outer shell of the heater 34, and is fully heated. The material reaches the lower cavity, swirls and evaporates through the swirl plate 7, and reaches the circulation pump 51 through the pump feed inlet 53. It then enters the upper cavity 4 of the heater 34 through the circulation pipe 52 and the central heat exchange tube 22. Under the forced circulation action of the circulation pump 51, it enters the lower part of the evaporator through the outer peripheral heat exchange tube 21. During the forced circulation process, it fully absorbs heat and evaporates. The vaporized gas after the material is heated enters the exhaust port 12 through the liquid separator 8 and is discharged. The material is processed in this way, with the feed and discharge continuously performing liquid forced circulation heat exchange operation.

Claims

1. A heat-pipe heat-recovery forced-circulation evaporator, characterized by, The utility model relates to a kind of evaporator, including: Heat exchange device, steam inlet (23) and condensate outlet (24) are provided on it, the heat exchange device includes center heat exchange pipe (22) and outer periphery heat exchange pipe (21), center heat exchange pipe (22) and outer periphery heat exchange pipe (21) are communicated with upper cavity (4), circulating material pipe (52) is communicated with center heat exchange pipe (22), outer periphery heat exchange pipe (21) is provided with the discharge port for cooperating circulating pump (51) to realize raw material circulation; Heating device is arranged outside heat exchange device, including heater (34) and feed cavity (32), the bottom side of feed cavity (32) is provided with opening and forms annular gap between heater (34), so that raw material forms falling film after being along the outside wall of heater (34) after feed cavity (32); Evaporator shell (1) is used to accommodate heat exchange device and heating device; Upper cavity (4) is covered on heat exchange device and is communicated with heat exchange device; Forced circulation device includes circulating pump (51) and circulating material pipe (52) arranged in the bottom of evaporator shell (1) inner side, circulating pump (51) is communicated with heat exchange device inside by circulating material pipe (52) and passes to upper cavity (4); Support tube (6) is arranged between the bottom side of heat exchange device and evaporator shell (1), and the outer ring of support tube (6) is provided with cyclone plate (7).

2. The internally heat-exchanging, forced-circulation evaporator of claim 1, wherein, Pump inlet (53) is arranged at the bottom of evaporator shell (1), and pump inlet (53) is connected with circulating pump (51) outside.

3. The internally heat-exchanging, forced-circulation evaporator of claim 1, wherein, Evaporator shell (1) is provided with exhaust port (12) in upper portion.

4. The internally heat-exchanging, forced-circulation evaporator of claim 3, wherein, Exhaust port (12) is provided with separator (8) for gas-liquid separation below.

5. The internally heat-exchanging, forced-circulation evaporator of claim 1, wherein, Operation hole (11) is arranged in the middle of the side of evaporator shell (1).

6. The internally heat-exchanging, forced-circulation evaporator of claim 1, wherein, Evaporator shell (1) is provided with mounting port in upper side, feed cavity (32) is clamped in mounting port, and feed cavity (32) is provided with material cavity fixing flange (35) and heat exchange fixing flange (25) in turn in upper side, material cavity fixing flange (35) is connected with feed cavity (32), and heat exchange fixing flange (25) is connected with heat exchange device.

7. The internally heat-exchanging, forced-circulation evaporator of claim 1 or 6, wherein, Upper tube plate (26) is arranged on the upper end of heat exchange device, and upper cavity flange (41) is connected on upper cavity (4), and upper cavity flange (41) is connected with upper tube plate (26) in cooperation.

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