A negative pressure generating device suitable for a vacuum evaporation system

Abstract

The utility model relates to the technical field of chemical equipment, and specifically is a negative pressure generating device suitable for a vacuum evaporation system, which comprises a steam pipeline connected with a steam generating device, and the end of the steam pipeline is connected with a condenser; the condenser is connected with a cooling water system through a cooling water pipeline, connected with a water seal pool through a condensate water pipeline, and connected with a vacuum pump through a gas pipeline; the utility model takes advantage of the characteristics that the intermolecular interval is rapidly and greatly reduced during rapid steam cooling, so that vacuum negative pressure can be rapidly generated in the condenser; the utility model further provides a cooling water cooling device in the cooling water system, which can cool the cooling water when the temperature is relatively high, prevents the cooling water from being gasified due to excessively high temperature, and ensures normal and stable operation of the system in a high-temperature environment in summer.

Description

Technical Field

[0001] This utility model relates to the field of chemical equipment technology, specifically a negative pressure generating device suitable for vacuum evaporation systems. Background Technology

[0002] In the production of bittern, the main process involves evaporating the moisture in the material to saturate and precipitate inorganic salts such as sodium chloride, potassium chloride, magnesium sulfate, and magnesium chloride. This process is then combined with other production steps to produce inorganic salt products. To reduce the energy consumption of evaporation, the most commonly used evaporation method is multi-effect vacuum evaporation. However, the negative pressure evaporation system in the evaporation process requires various vacuum equipment. The large number of vacuum equipment not only increases the construction and installation costs but also significantly increases the subsequent production and maintenance costs, thus reducing production efficiency. Utility Model Content

[0003] The purpose of this invention is to provide a negative pressure generating device that can be used in vacuum evaporation systems without requiring a combination of multiple vacuum pumping devices.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: A negative pressure generating device suitable for a vacuum evaporation system includes a steam pipe connected to a steam generator, a condenser connected to the end of the steam pipe, a steam inlet at the bottom of the condenser, and the steam pipe connected to the steam inlet; a cooling water inlet at the top of the condenser, a condensate outlet at the bottom, and a gas outlet at the top; a cooling water system connected to the cooling water inlet of the condenser via a cooling water pipe, a condensate outlet connected to a water seal tank via a condensate pipe, and a gas outlet connected to a vacuum pump via a gas pipe.

[0005] Preferably, a hollow annular distributor is fitted on the outside of the condenser, and the distributor is connected to the cooling water inlet; multiple nozzles are evenly distributed in a ring inside the condenser, and each nozzle is connected to the distributor.

[0006] Preferably, there are multiple distributors and multiple parallel branches in the cooling water pipeline, with each branch connected to a corresponding distributor.

[0007] Preferably, multiple evaporators are connected in series between the steam generator and the condenser. The inlet of the evaporator is located at the bottom and the outlet is located at the top. The outlet of the last stage evaporator is connected to the steam inlet of the condenser through a steam pipe.

[0008] Preferably, there are two evaporators.

[0009] Preferably, the cooling water system includes a cooling water tank, which is connected to the condenser via a cooling water pipe; the bottom of the cooling water tank is also connected to a cooling water cooling device via a cooling pipe, and the outlet of the cooling water cooling device is connected to the cooling water pipe.

[0010] Preferably, an inspection hole is provided on the side wall of the condenser.

[0011] The beneficial effects of this utility model are: This invention is based on the principle of rapid condensation of steam leading to a rapid reduction in volume. After entering the condenser, the steam is rapidly cooled and condensed by cooling water, reducing its volume by more than 1600 times, thereby quickly forming a vacuum negative pressure state. At the same time, a gas outlet connected to a vacuum pump is provided to extract some of the air entrained in the steam, further improving the vacuum degree. According to tests, this invention can form a vacuum system with a vacuum degree of -0.09 kPa to -0.099 kPa.

[0012] This invention also includes an additional cooling water cooling device in the cooling water system, which can cool the cooling water to a suitable temperature before it is introduced into the condenser in high-temperature environments in summer. By pre-cooling the cooling water, vaporization of the cooling water due to excessive temperature can be avoided, thereby ensuring the stable operation of the system under high-temperature conditions in summer. Attached Figure Description

[0013] Figure 1 This is a flowchart of the present invention; Figure 2 This is a schematic diagram of the internal structure of the condenser of this utility model.

[0014] In the diagram: 1. Condenser; 2. Evaporator; 3. Cooling water tank; 4. Cooling water cooling device; 5. Water seal pool; 6. Vacuum pump; 7. Steam inlet; 8. Cooling water inlet; 9. Distributor; 10. Nozzle; 11. Gas outlet; 12. Condensate outlet; 13. Inspection hole. Detailed Implementation

[0015] The following is a further explanation of the present invention in conjunction with specific embodiments, such as... Figure 1 and Figure 2 As shown, this embodiment is a negative pressure generating device suitable for a vacuum evaporation system, including a steam pipe connected to a steam generating device, and a condenser 1 connected to the end of the steam pipe.

[0016] like Figure 2As shown, the condenser 1 has a condensate outlet 12 at its bottom and a gas outlet 11 at its top. A steam inlet 7 and a cooling water inlet 8 are respectively provided on its side wall. A steam pipe connects to the condenser 1 through the steam inlet 7. In this embodiment, there are two cooling water inlets 8, one above the other, and both inlets are higher than the steam inlet 7. Two distributors 9 are also provided on the outer side wall of the condenser 1. Each distributor 9 has a hollow annular structure and connects to one of the two cooling water inlets 8, allowing cooling water introduced at the inlets 8 to enter the distributors 9 and distribute evenly around the condenser 1. An inspection hole 13 is also provided between the two distributors 9 of the condenser 1 for maintenance and repair.

[0017] Multiple nozzles 10 are provided inside the condenser 1. The nozzles 10 are divided into two groups and are evenly distributed circumferentially inside the condenser 1. The two groups of nozzles 10 are respectively connected to two distributors 9, so that the cooling water in the distributors 9 can be evenly sprayed into the condenser 1 through the nozzles 10.

[0018] like Figure 1 As shown, a steam pipe connects to an evaporator 2, and the top of the evaporator 2 is connected to the condenser 1 via a secondary steam pipe. In this embodiment, two evaporators 2 are connected in series, and the two evaporators 2 are connected to each other via a secondary steam pipe. The lower inlet of the first evaporator 2 is connected to a steam generator via a steam pipe, and the top outlet is connected to the lower outlet of the second evaporator 2 via a secondary steam pipe. The live steam generated in the steam generator can be evaporated twice by the evaporator 2 and then enter the bottom of the condenser 1 through the secondary steam pipe.

[0019] The cooling water inlet 8 of the condenser 1 is connected to the cooling water tank 3 via a cooling water pipe. The cooling water tank 3 can input cooling water into the condenser 1 through the cooling water pipe. The cooling water pipe is provided with two parallel branches, which are connected to the two cooling water inlets 8 respectively. In this embodiment, the cooling water is seawater (white water), that is, seawater, tap water and condensate used in the chemical plant production process. In order to prevent the cooling water from evaporating in the hot summer weather, the cooling water tank 3 is also connected to the cooling water cooling device 4 via a cooling pipe in this embodiment. The cooling water cooling device 4 is also connected to the condenser via a cooling water pipe. When the temperature is too high, the cooling water cooling device 4 is turned on so that the cooling water in the cooling water tank 3 is cooled down by the cooling water cooling device 4 before being introduced into the condenser 1 for condensation.

[0020] The top gas outlet 11 of the condenser 1 is connected to a vacuum pump 6 via a gas pipe. The vacuum pump 6 is used to extract the small amount of air contained in the steam entering the condenser 1, thereby further improving the vacuum level in the condenser 1. The bottom condensate outlet 12 of the condenser 1 is connected to a water seal tank 5 via a condensate pipe. The water seal tank 5 forms a closed environment, ensuring the overall sealing of the system.

[0021] In practical use, the steam generated by the steam generator enters the evaporator 2 and is heated in the heating chamber inside the evaporator 2, causing the residual water to evaporate into steam, i.e., secondary evaporation. After secondary evaporation through the two evaporators 2, the steam forms relatively pure steam and enters the condenser 1 through the steam inlet 7. At the same time, cooling water is introduced into the distributor 9 through the cooling water pipe and sprayed evenly into the condenser 1 through the nozzle 10. The high-temperature steam will quickly condense into a liquid state after contacting the low-temperature cooling water. Since the molecular spacing of gaseous steam is relatively large, the molecular spacing will decrease rapidly and significantly after cooling into a liquid state, resulting in a rapid reduction of the total volume by more than 1600 times. This leads to a rapid formation of a vacuum negative pressure inside the condenser 1, which can form a vacuum system with a vacuum degree of -0.09 kPa to -0.099 kPa.

[0022] The condensate and excess cooling water generated during the condensation process can be discharged through the condensate outlet 12 at the bottom of the condenser 1. However, some air mixed in with the steam cannot be condensed, so this part of the gas is extracted by the vacuum pump 6 connected to the top gas outlet.

[0023] When the ambient temperature is high, causing the cooling water temperature to exceed 30°C, the seawater (white water) may vaporize under a certain vacuum when its temperature rises during the cooling of secondary steam. In this case, it is necessary to close the cooling water pipeline between the cooling water tank 3 and the condenser 1, and open the cooling pipeline to connect the cooling water tank 3 and the cooling water cooling device 4. The cooling water is first cooled down to the temperature required for production, and then introduced into the condenser 1 through the cooling water pipeline, thereby ensuring the stable operation of the system under high temperature conditions in summer.

[0024] The above description is merely a further explanation of the present utility model in conjunction with specific embodiments. All descriptions made do not imply any limitation on the protection scope of the present utility model. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present utility model should be included within the protection scope of the present utility model. Therefore, the protection scope of the present utility model should be determined by the protection scope of the claims.

Claims

1. A negative pressure generating device suitable for a vacuum evaporation system, comprising a steam pipe connected to a steam generating device, characterized in that: The end of the steam pipe is connected to a condenser, and the lower part of the condenser is provided with a steam inlet, which is connected to the steam inlet by the steam pipe. The upper part of the condenser is provided with a cooling water inlet, the bottom is provided with a condensate outlet, and the top is provided with a gas outlet. The cooling water system is connected to the cooling water inlet of the condenser through a cooling water pipe, the condensate outlet is connected to the water seal tank through a condensate pipe, and the gas outlet is connected to the vacuum pump through a gas pipe.

2. The negative pressure generating device for a vacuum evaporation system according to claim 1, characterized in that: The condenser is fitted with a hollow annular distributor on its outer side, and the distributor is connected to the cooling water inlet; multiple nozzles are evenly distributed in a ring inside the condenser, and each of the multiple nozzles is connected to the distributor.

3. The negative pressure generating device for a vacuum evaporation system according to claim 2, characterized in that: The distributor is provided in multiple ways, and the cooling water pipeline is provided in multiple parallel branches, each branch being connected to the corresponding distributor.

4. The negative pressure generating device for a vacuum evaporation system according to claim 1, characterized in that: Multiple evaporators are connected in series between the steam generator and the condenser. The inlet of the evaporator is located at the bottom and the outlet is located at the top. The outlet of the last stage evaporator is connected to the steam inlet of the condenser through a steam pipe.

5. The negative pressure generating device for a vacuum evaporation system according to claim 4, characterized in that: There are two or more evaporators.

6. The negative pressure generating device for a vacuum evaporation system according to claim 1, characterized in that: The cooling water system includes a cooling water tank, which is connected to the condenser via a cooling water pipe; the bottom of the cooling water tank is also connected to a cooling water cooling device via a cooling pipe, and the outlet of the cooling water cooling device is connected to the cooling water pipe.

7. The negative pressure generating device for a vacuum evaporation system according to claim 1, characterized in that: The condenser has an inspection hole on its side wall.

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