Multi-layer composite concentrator

Abstract

The utility model discloses a multi-layer composite concentrator which comprises a plurality of evaporation units arranged in the longitudinal direction, and each evaporation unit comprises a feed port, a discharge port and a secondary steam outlet; the straight pipe is connected with a secondary steam outlet of the front-effect evaporation unit and a heating evaporation chamber of the rear-effect evaporation unit, and a secondary steam outlet of the tail-effect evaporation unit of the concentrator is connected with a secondary steam pipeline; the middle pipeline is connected with the discharge port and the feed port of the after-effect evaporation unit, and the straight pipe and the middle pipeline are arranged in the shell. The plurality of evaporation units in the longitudinal direction form a tower structure, secondary steam generated by the front-effect evaporation unit is guided into the heating evaporation chamber of the rear-effect evaporation unit through the straight pipe, steam pressure loss is reduced, the middle pipeline is connected with the discharge port of the front-effect evaporation unit and the feed port of the rear-effect evaporation unit, and the steam pressure loss is reduced. Compared with a traditional multi-effect evaporator, the arrangement of a pump is reduced. And the straight pipe and the middle pipeline are arranged in the shell, so that the heat loss in the material liquid and steam transfer process is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of evaporation concentrators, in particular to a multi-effect evaporation concentrator. Background Art

[0002] One of the more common concentrators is the evaporation concentrator, including a single-effect concentrator and a multi-effect concentrator. The multi-effect concentrator has multiple evaporation units. The secondary steam generated by the previous evaporation unit is input into the next evaporation unit for reuse, so as to achieve the purpose of reducing the amount of live steam used. For example, a multi-effect evaporation concentration system and its treatment process disclosed in a Chinese invention patent with the publication number CN117531215A uses multiple evaporation tanks for multi-effect treatment. In fact, since the subsequent-effect evaporator of the multi-effect evaporator uses the secondary steam generated by the previous-effect evaporator for heating, the pressure and temperature of the subsequent-effect evaporator decrease in sequence. The steam evaporation amount of the evaporator is related to the heat transfer amount. The multi-effect evaporator does not generate a larger amount of steam than the single-effect circulation evaporator. Therefore, the multi-effect evaporator cannot improve the production efficiency. Its advantage is that it reduces the use amount of live steam, and its disadvantages are large floor area, large equipment investment, and the connecting pipes are arranged outside the evaporator, resulting in heat loss. In addition, for materials with low concentration requirements, the production efficiency of the multi-effect evaporator is not high. Summary of the Invention

[0003] Aiming at the above deficiencies, the purpose of the utility model is to provide an evaporation concentrator with reduced floor area.

[0004] To this end, a multi-level composite concentrator includes a plurality of evaporation units arranged longitudinally. The evaporation unit includes a feed inlet, a discharge outlet, and a secondary steam outlet. A straight pipe connects the secondary steam outlet of the previous-effect evaporation unit to the heating evaporation chamber of the subsequent-effect evaporation unit. Among them, the secondary steam outlet of the last-effect evaporation unit of the concentrator is connected to a secondary steam pipe. An intermediate pipe connects the discharge outlet and the feed inlet of the subsequent-effect evaporation unit, and the straight pipe and the intermediate pipe are arranged in a housing.

[0005] Further, the evaporation unit includes an upper cavity and a heating evaporation chamber. The feed inlet and the secondary steam outlet are arranged in the upper cavity. The upper cavity is connected to a heating pipe, and the heating evaporation chamber is connected to a condensate pipe.

[0006] Further, the evaporation unit is provided with a separate feed pipe and a discharge pipe. The feed pipe is used to directly input the liquid material into the upper cavity from the outside, and the discharge pipe is used to discharge the liquid material after evaporation and concentration from the concentrator.

[0007] Further, a first solenoid valve and a second solenoid valve are sequentially arranged on the intermediate pipe from top to bottom. The first solenoid valve and the second solenoid valve are three-way valves. The discharge pipe is connected to the first solenoid valve, and the feed pipe is connected to the second solenoid valve.

[0008] Further, the first solenoid valve and the second solenoid valve are arranged in a partition layer.

[0009] Further, the feed pipe is arranged in the condensed water at the bottom of the heating evaporation chamber of the first-effect evaporation unit.

[0010] Further, a partition plate with a middle part convex towards the heating evaporation chamber is arranged at the bottom of the first-effect evaporation unit, and an annular groove is jointly formed by the outer side of the partition plate and the inner wall of the shell. A condensed water pipe is connected to the side wall of the groove. The feed pipe is arranged along the annular groove, and a through hole for the feed pipe to extend downward is arranged in the annular groove.

[0011] Further, a reserved section is arranged in the groove, and one end of the straight pipe passes through the reserved section.

[0012] Further, a baffle is arranged at the bottom of the partition plate to form a cavity. The lower end of the heating pipe is communicated with the cavity. The baffle is provided with holes, and the straight pipe passes through the holes in the baffle to communicate the cavity with the upper cavity of the second-effect evaporation unit.

[0013] The beneficial technical effects of the present utility model are as follows:

[0014] (1) For a multi-level composite concentrator of the present utility model, a plurality of evaporation units form a tower structure longitudinally. The secondary steam generated by the first-effect evaporation unit is introduced into the heating evaporation chamber of the second-effect evaporation unit through a straight pipe, reducing the steam pressure loss. The intermediate pipe connects the discharge port of the first-effect evaporation unit and the feed port of the second-effect evaporation unit, and the liquid material is transferred by gravity. Compared with the traditional multi-effect evaporator that relies on a pump to complete the transfer of the liquid material between the first-effect evaporation unit and the second-effect evaporation unit, the setting of the pump is reduced. The straight pipe and the intermediate pipe are arranged in the shell, avoiding or reducing the heat loss during the transfer of the liquid material and the steam.

[0015] (2) In a specific embodiment of the present utility model, the evaporation unit is also provided with a separate feed pipe and a discharge pipe, enabling each evaporation unit to be used as an independent single-effect evaporator, and the condensed water of the first-effect evaporator can also be used to preheat the feed, thus avoiding the setting of a preheater before each evaporation unit and saving equipment investment. Description of the Drawings

[0016] Figure 1 Schematic diagram of a specific embodiment for implementing the present utility model;

[0017] Figure 2 Top view schematic diagram of the partition plate.

[0018] Description of the reference numerals: 1. Evaporation unit; 2. Feed inlet; 3. Discharge outlet; 4. Secondary steam outlet; 5. Straight pipe; 6. Heating evaporation chamber; 7. Heating pipe; 8. Shell; 9. Intermediate pipe; 10. Upper cavity; 11. Condensate pipe; 12. Feed pipe; 13. Discharge pipe; 14. First solenoid valve; 15. Second solenoid valve; 16. Interlayer; 17. Baffle; 18. Groove; 19. Cavity; 20. Baffle plate; 21. Reserved section. Detailed implementation mode

[0019] To further elaborate on the technical means and effects adopted by the present utility model to achieve the predetermined utility model purpose, the following, in conjunction with the accompanying drawings and preferred embodiments, details the specific implementation mode, structure, features and their effects of the present utility model as follows.

[0020] Refer to Figure 1 And Figure 2 As shown, a multi-level composite concentrator of the present utility model includes a plurality of evaporation units 1 arranged longitudinally. The evaporation unit 1 includes a heating evaporation chamber 6, a heating pipe 7, a feed inlet 2, a discharge outlet 3 and a secondary steam outlet 4. A straight pipe 5 connects the secondary steam outlet 4 of the previous-effect evaporation unit 1 to the heating evaporation chamber 6 of the subsequent-effect evaporation unit 1. Among them, the secondary steam outlet 4 of the last-effect evaporation unit 1 of the concentrator is connected to a secondary steam pipe. An intermediate pipe 9 connects the discharge outlet 3 and the feed inlet 2 of the subsequent-effect evaporation unit 1. The straight pipe 5 and the intermediate pipe 9 are arranged in a shell 8. In this embodiment, a falling-film evaporation concentrator is adopted. The main body of the evaporation unit 1 is a heating evaporation chamber 6, and a multi-level composite concentrator is formed by longitudinal combination. The uppermost one is the first-effect evaporation unit, and the lowermost one is the last-effect evaporation unit. Intermediate evaporation units can also be arranged between the first-effect evaporation unit and the last-effect evaporation unit. Among them, the first-effect evaporation unit feeds from the outside and inputs live steam (steam input from the outside) into the heating evaporation chamber 6. The last-effect evaporation unit 1 forms the final product, and the secondary steam generated by its evaporation is discharged through the secondary steam pipe. The evaporation unit 1 also includes an upper cavity 10. The feed inlet 2 and the secondary steam outlet 4 are arranged in the upper cavity 10. The straight pipe 5 connects the upper cavity 10 and the heating evaporation chamber 6 of the subsequent effect. The upper cavity 10 is connected to the heating pipe 7. The liquid material enters the upper cavity 10 from the feed inlet 2 and then descends along the wall of the heating pipe 7 in a film shape for heat exchange. After the liquid material is heated and evaporated through the heating pipe 7, it enters the subsequent-effect evaporation unit through the intermediate pipe. The steam in the heating evaporation chamber 6 condenses to form condensate and is discharged from the condensate pipe 11 connected to the lower part of the heating evaporation chamber 6. The main function of this embodiment is to combine multiple evaporation units 1 to form a tower-shaped structure, which is compact in structure and saves floor space. The liquid material flows from top to bottom, reducing the pressure loss of the liquid material. There is no need to set a pump for pressurization, and both the secondary steam and the liquid material are transferred in the shell 8, reducing heat loss.

[0021] In the above embodiment, for the feed liquid with low concentration requirements, it can be concentrated by a single cycle through a single-effect evaporator. Figure 1 As shown in FIG. 1 , in this embodiment, the evaporation unit 1 is provided with a separate feed pipe 12 and a discharge pipe 13, and the intermediate pipe 9 is provided with a first solenoid valve 14 and a second solenoid valve 15 from top to bottom, the first solenoid valve 14 and the second solenoid valve 15 are three-way valves, and the first solenoid valve 14 and the second solenoid valve 15 are controlled by a control system, the discharge pipe 13 is connected to the first solenoid valve 14, and the feed pipe 12 is connected to the second solenoid valve 15. The first solenoid valve 14 and the second solenoid valve 15 can be arranged in the interlayer 16 between the two evaporation units 1. When used as a multi-effect evaporation concentrator, the first solenoid valve 14 and the second solenoid valve 15 are controlled so that the pipe between the first solenoid valve 14 and the second solenoid valve 15 is connected, the straight pipe 5 is connected to the upper chamber 10 of the after-effect evaporation unit 1, and the feed pipe 12 and the discharge pipe 13 are closed. When used as a single-effect evaporation concentrator, the first solenoid valve 14 and the second solenoid valve 15 are controlled so that the pipeline between the first solenoid valve 14 and the second solenoid valve 15 is closed, the discharge pipeline 13 is opened, and the liquid of the front-effect evaporation unit 1 is discharged from the discharge port 3 through the first solenoid valve 14 and the discharge pipeline 13; the second solenoid valve 15 controls the feed pipeline 12 to be connected with the feed port 2 of the rear-effect evaporation unit 1, and the feed liquid enters the upper chamber 10 of the rear-effect evaporation unit 1 from the outside through the feed pipeline 12 and the second solenoid valve 15, so that the concentrator can be used as multiple separate single-effect evaporation concentrators or several of them can be freely selected to be used as two-effect evaporators or multiple-effect evaporators.

[0022] In the above embodiments, refer to Figure 1 As shown in , the feed pipe 12 is arranged in the condensed water at the bottom of the heating evaporation chamber 6 of the front-effect evaporation unit 1. When used as a single-effect evaporation concentrator, the condensed water of the front-effect evaporation unit 1 is used to preheat the feed of the rear-effect evaporation unit 1, thereby avoiding the need to set up a separate preheater and saving equipment investment. Specifically, a partition 17 with a middle portion convex toward the heating evaporation chamber 6 can be provided at the bottom of the front-effect evaporation unit 1, and an annular groove 18 is formed on the outer side of the partition 17 and the inner wall of the shell 8. The condensed water pipe 11 is connected to the side wall of the groove 18, and the feed pipe is arranged along the annular groove 18. A through hole for the feed pipe to extend downward is provided in the annular groove 18. The purpose of providing the groove is to prevent the condensed water from contacting the heating pipe and affecting the liquid temperature in the heating pipe after the feed pipe and the condensed water have exchanged heat. By controlling the condensed water discharge from the condensed water pipe, the height of the condensed water can be controlled not to exceed the top of the groove. Refer to Figure 1 ​​As shown, a baffle 20 is provided at the bottom of the partition plate 17 to form a cavity 19. The lower end of the heating pipe 7 communicates with the cavity 19. The baffle 20 is provided with holes, and the straight pipe 5 passes through the holes on the baffle 20 to communicate the cavity 19 with the upper cavity 10 of the post-effect evaporation unit 1. In this embodiment, the annular feed pipe can increase the contact time with the condensed water and increase the temperature of the feed. Although the annular elbow causes a certain pressure loss of the liquid material to a certain extent, the application scenario of this embodiment is a single-effect evaporation concentrator, and the concentration of the liquid material in the feed is not high and the fluidity is good. This structure will not significantly affect the feed.

[0023] In the above embodiment, referring to Figure 2 As shown, a reserved section 21 is provided. The upper surface of the reserved section can be flush with the top surface or the bottom surface of the groove. When the reserved section 21 is a part of the groove, no pipeline is provided in the reserved section, and one end of the straight pipe 5 passes through the reserved section and extends into the upper cavity 10.

[0024] The above are only the preferred embodiments of the present invention, and do not impose any form of limitation on the present invention. Although the present invention has been disclosed above with the preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some changes or modifications to equivalent embodiments by using the technical content disclosed above without departing from the technical solution of the present invention. However, as long as it does not depart from the technical solution content of the present invention, any brief modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A multi-level composite concentrator, characterized in that: It comprises a plurality of evaporation units arranged in the longitudinal direction, wherein the evaporation units comprise a feed port, a discharge port and a secondary steam outlet; a straight pipe connects the secondary steam outlet of the front-effect evaporation unit with the heating evaporation chamber of the rear-effect evaporation unit, wherein the secondary steam outlet of the rear-effect evaporation unit of the concentrator is connected to the secondary steam pipeline; an intermediate pipeline connects the discharge port and the feed port of the rear-effect evaporation unit, and the straight pipe and the intermediate pipeline are arranged in a shell.

2. A multi-level composite concentrator according to claim 1, characterized in that: The evaporation unit comprises an upper cavity and a heating evaporation chamber, the feed inlet and the secondary steam outlet are arranged in the upper cavity, the upper cavity is connected to a heating pipe, and the heating evaporation chamber is connected to a condensed water pipeline.

3. A multi-level composite concentrator according to claim 2, characterized in that: The evaporation unit is provided with a separate feed pipe and a discharge pipe. The feed pipe is used to directly input feed liquid from the outside into the upper cavity, and the discharge pipe is used to discharge the feed liquid after evaporation and concentration from the concentrator.

4. A multi-level composite concentrator according to claim 3, characterized in that: The intermediate pipeline is provided with a first solenoid valve and a second solenoid valve in sequence from top to bottom, the first solenoid valve and the second solenoid valve are third-way valves, the discharge pipeline is connected to the first solenoid valve, and the feed pipeline is connected to the second solenoid valve.

5. A multi-level composite concentrator according to claim 4, characterized in that: The first solenoid valve and the second solenoid valve are arranged in the partition.

6. A multi-level composite concentrator according to any one of claims 3 to 5, characterized in that: The feed pipe is arranged in the condensed water at the bottom of the heating evaporation chamber of the pre-effect evaporation unit.

7. A multi-level composite concentrator according to claim 6, characterized in that: The bottom of the evaporation unit of the front effect is provided with a partition with a middle part protruding toward the heating evaporation chamber, and an annular groove is formed on the outer side of the partition and the inner wall of the shell. The side wall of the groove is connected to the condensate pipe. The feed pipe is arranged along the annular groove, and a through hole is provided in the annular groove for the feed pipe to extend downward.

8. A multi-level composite concentrator according to claim 7, characterized in that: A reserved section is arranged in the groove, and one end of the straight pipe passes through the reserved section.

9. The multi-level composite concentrator according to claim 7, characterized in that: A baffle is arranged at the bottom of the partition to form a cavity, the lower end of the heating tube is connected with the cavity, the baffle is provided with a hole, and the straight tube passes through the hole on the baffle to connect the cavity with the upper volume cavity of the after-effect evaporation unit.

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