CN210952419U - A salt cooling device for acetylene polymerization reaction gas - Google Patents

Abstract

The utility model relates to the technical field of rubber production, and discloses a salt cooling device for acetylene polymerization reaction gas. The wire mesh demister in the salt cooling tower, the lower part of the salt cooling tower is connected with the reaction gas inlet pipe; the lower part of the salt cooling tower is provided with a concentration tower, the lower part of the concentration tower is connected with the bottom of the salt cooling tower, and the The top is communicated with a NaCl inlet pipe, and the lower part of the concentration tower is communicated with a pump assembly; it also includes a cooler, the bottom of the cooler communicates with the pump assembly, and the top of the cooler communicates with a cooling pipe communicated with the upper part of the salt cooling tower. The utility model is convenient for cooling the reaction gas.

Description

A salt cooling device for acetylene polymerization reaction gas

technical field

The utility model relates to the technical field of rubber production, in particular to a salt cooling device for acetylene polymerization reaction gas.

Background technique

Acetylene dimerization to prepare vinyl acetylene is an important operation unit for the production of chloroprene rubber by acetylene method in my country. The reaction gas of vinyl acetylene is generated (MVA is about 3-5%, and most of the rest is acetylene), which is absorbed by xylene as an absorbent. MVA (vinyl acetylene), in order to ensure the absorption efficiency, the reaction gas needs to be cooled to about -7°C. In the prior art, a cooler is generally used for cooling, and the existing cooler generally uses water cooling or air as a coolant. However, due to the large gas volume of the reaction gas for generating vinyl acetylene, the required temperature is low, and the existing cooler is difficult to achieve. Therefore, it is necessary to study the cooling of acetylene dimerization reaction gas.

Utility model content

The utility model is intended to provide a salt cooling device for acetylene polymerization reaction gas, so as to solve the problem that the existing cooler is difficult to meet the cooling requirement of the reaction gas of vinyl acetylene.

In order to achieve the above purpose, the utility model provides the following technical scheme: a salt cooling device for acetylene polymerization reaction gas, comprising a salt cooling tower, the top of the salt cooling tower is connected with a reaction gas exhaust pipe, and the bottom of the reaction gas exhaust pipe is arranged There is a wire mesh demister located in the salt cooling tower, and the lower part of the salt cooling tower is connected with a reaction gas inlet pipe;

A concentration-enhancing tower is arranged below the salt-cooling tower, the lower part of the concentration-enhancing tower is connected with the bottom of the salt-cooling tower, the top of the concentration-enhancing tower is connected with a NaCl inlet pipe, and the lower part of the concentration-enhancing tower is connected with a pump assembly;

It also includes a cooler, the bottom of the cooler is communicated with the pump assembly, and the top of the cooler is communicated with a cooling pipe communicated with the upper portion of the salt cooling tower.

The principle and beneficial effects of the utility model: the reaction gas enters the salt cooling tower from the water cooling tower through the reaction gas inlet pipe, and is then cooled and cooled by the NaCl solution sprayed into the salt cooling tower, and the cooled reaction gas passes through the wire mesh demister , The reaction gas exhaust pipe is discharged from the salt cooling tower. Since there is a small amount of water in the reaction gas, the NaCl solution will be diluted, which will affect the freezing point of the NaCl solution. At the same time, some high-boiling substances will also be cooled to form the CH phase, and the concentration of the NaCl solution will decrease. Therefore, the NaCl solution after cooling the reaction gas It will be discharged into the thickening tower, and NaCl will be added to the NaCl solution in the thickening tower intermittently to ensure the density and quantity of the circulating NaCl solution.

The pump assembly sends the NaCl solution into the cooler, and cools it down in the cooler, so that the temperature of the NaCl solution reaches -13°C, and then enters the salt cooling tower to reduce the temperature of the reaction gas to -5～- 7°C to facilitate the absorption of the reaction gas by the xylene solvent.

It is difficult for the traditional cooler to reduce the temperature of the reaction gas to -7°C. In the present application, through the coordination of the salt cooling tower, the enrichment tower and the cooler, the temperature of the reaction gas can be reduced to -5 to -7°C, so that the reaction gas can be reduced to -5 to -7°C. More easily absorbed by xylene solvent.

Further, the lower part of the salt cooling tower is connected with a CH phase liquid drain pipe located below the reaction gas inlet pipe. In the salt cooling tower, some high-boiling substances will be cooled to form CH phase, and the CH phase will be discharged through the CH phase drain pipe.

Further, the aperture of the wire mesh demister is 3-5um. Remove more than 98% of the droplets of 3-5um to avoid entrainment of the mist, and achieve the purpose of separating the NaCl solution from the reaction gas as much as possible.

Further, several evenly distributed trays or packings are arranged in the salt cooling tower along its axial direction, and the packings or trays are located below the wire mesh demister. The reaction gas and the NaCl solution are in full contact and heat exchange on the packing or column plate, so that the reaction gas is fully cooled.

Further, an absorption tower is also included, and the absorption tower is communicated with the reaction exhaust pipe. The absorption tower is used to absorb the reaction gas.

Further, the outside of the cooling pipe is provided with a thermal insulation layer. The temperature of the NaCl solution cooled by the cooler is low and lower than the temperature of the air, and it is easy to exchange heat with the air, which leads to an increase in the temperature of the NaCl solution. Therefore, the NaCl solution in the cooling pipe is kept warm by the thermal insulation layer.

Further, a feeder is also included, and the feeder is communicated with the NaCl inlet pipe. The NaCl solution in the thickening tower needs to increase the concentration, and the NaCl solid particles are added to the thickening tower through the feeder to avoid the concentration of the NaCl solution being too low.

Further, the feeder includes a box body with an opening at the top, a closing block closing the opening at the opening, a discharge port communicating with the NaCl inlet pipe at the bottom of the box body, and a rotary valve on the NaCl inlet pipe. Open the rotary valve to send the NaCl solid particles in the box into the thickening tower. The closure block closes the opening, reducing the amount of air entering the box, thereby reducing the chance of the NaCl solids getting wet.

Further, the inner wall of the box body is provided with a moisture-proof layer. The moisture barrier blocks the moisture in the air from entering the NaCl solid particles.

Further, a phase separator is communicated with the CH phase liquid discharge pipe. The CH phase extracted from the salt cooling tower enters the separator through the CH phase drain pipe for separation treatment.

Description of drawings

Fig. 1 is the axial view of the salt cooling device of acetylene polymerization reaction gas in the first embodiment of the utility model;

Fig. 2 is the front partial sectional view of the salt cooling device of acetylene polymerization reaction gas in the first embodiment of the present utility model;

Fig. 3 is the enlarged view of A part in Fig. 2;

FIG. 4 is the feeder in the second embodiment.

Detailed ways

The following is further described in detail by specific embodiments:

Reference numerals in the accompanying drawings include: cooler 1, salt cooling tower 2, wire mesh demister 21, tray 22, flange 23, reaction gas inlet pipe 24, bolt 25, enrichment tower 3, centrifugal Pump 4 , box 5 , moisture-proof layer 51 , closing block 52 , rotary valve 53 .

Example 1:

Basically as shown in Figure 1, Figure 2 and Figure 3, a salt cooling device for acetylene polymerization reaction gas includes a salt cooling tower 2, and in this embodiment, the salt cooling tower 2 is a plate tower.

The upper part of the salt cooling tower 2 is provided with a flange 23 , and the flange 23 is fixed on the salt cooling tower 2 by bolts 25 . The top of the salt cooling tower 2 is provided with a wire mesh demister 21 , and the grille of the wire mesh demister 21 is welded on the flange 23 . In this embodiment, the wire mesh demister 21 of HG/T21618-1998 is used, and the aperture in this embodiment is 3um. The bottom of the wire mesh demister 21 is provided with several trays 22 or packings that are uniformly distributed along the axial direction of the salt cooling tower 2. In this embodiment, the tray 22 is selected, and the tray 22 is a tray 22 commonly used in industry. Here No longer.

The top of the salt cooling tower 2 is connected with a reaction gas exhaust pipe, and the reaction gas exhaust pipe is connected with an absorption tower. The lower left side of the salt cooling tower 2 is communicated with a reaction gas inlet pipe 24, the reaction gas inlet pipe 24 is communicated with the water cooling tower, the lower right side of the salt cooling tower 2 is communicated with a CH phase liquid drain pipe, and the CH phase liquid drain pipe is located in the reaction gas. Below the intake pipe 24, the CH phase liquid discharge pipe is connected with a separator (not shown in the figure). MVA is gas, CH phase density: 866Kg/m3, brine density: 1140Kg/m3, MVA gas will not enter the separator, CH and brine will be automatically stratified in the separator, the upper layer is CH phase solution, and the bottom is brine, The CH phase solution is discharged into the separator from the CH phase drain pipe.

The bottom of the salt cooling tower 2 is provided with a thickening tower 3, the top of the thickening tower 3 is connected with a NaCl inlet pipe, and the lower part of the thickening tower 3 is communicated with the bottom of the salt cooling tower 2 through pipes. It also includes a pump assembly. In this embodiment, the pump assembly is a centrifugal pump 4. The liquid inlet of the centrifugal pump 4 is communicated with the lower part of the concentration tower 3 through a pipeline, and the liquid outlet of the centrifugal pump 4 is communicated with the cooler 1 and is connected with the cooler. The bottom of 1 is communicated with, the top of the cooler 1 is communicated with a cooling pipe, and the other end of the cooling pipe is communicated with the upper part of the salt cooling tower 2 . The outside of the cooling pipe is provided with a thermal insulation layer, and in this embodiment, the thermal insulation layer is an asbestos board thermal insulation layer. The cooler 1 is a tubular cooler, which is commonly used in the industry, and will not be repeated here.

The specific implementation process is as follows:

The reaction gas in the water cooling tower enters the lower part of the salt cooling tower 2 through the reaction gas inlet pipe 24, and the reaction gas will flow upward. During the upward flow of the reaction gas, it will meet the NaCl solution sprayed into the salt cooling tower 2, and the NaCl solution absorbs heat on the reaction gas, so that the temperature of the reaction gas is reduced to -5～-7℃, and the reaction gas After the temperature is lowered, it will pass through the wire mesh demister 21. The wire mesh demister 21 can block most of the droplets with a particle size larger than 0.9um in the reaction gas, so as to achieve the purpose of separating the reaction gas from the NaCl solution. The reaction gas enters the absorption tower through the reaction gas exhaust pipe to complete the cooling of the reaction gas.

Under the action of the column plate 22, the reaction gas and the NaCl solution are fully contacted on the column plate to exchange heat, so that the reaction gas is fully cooled.

The NaCl solution finally enters into the thickening tower 3 from the bottom of the salt cooling tower 2, and intermittently fills the NaCl solid particles into the thickening tower 3 through the NaCl inlet pipe so that the concentration of the NaCl solution is not too low to ensure the density of the NaCl solution. At 1140-1160Kg/m3. The centrifugal pump 4 sends the NaCl solution into the cooler 1 for cooling, so that the temperature of the NaCl solution is reduced to -13 ° C, and then sprayed to the upper part of the salt cooling tower 2 through the cooling pipe, and the cold circulation of the NaCl solution is passed through the above process. , and the NaCl solution enrichment cycle.

In this embodiment, the high-boiling substances in the salt cooling tower 2 will be cooled by the NaCl solution to form a CH phase solution. The CH phase solution is extracted from the salt cooling tower 2 and then enters the separator through the CH phase drain pipe. The separation of the CH phase solution is carried out, and the separation of the CH phase solution is not a problem to be solved in this application, and will not be repeated here.

Embodiment 2:

The difference from Embodiment 1 is that, as shown in FIG. 4 , a feeder for supplying NaCl solid particles to the enrichment tower 3 is provided, and the feeder includes a box body 5, and the upper part of the box body 5 is provided with an opening and a closed opening. The outer periphery of the closing block 52 is provided with a rubber layer. When the closing block 52 extends into the opening, the rubber layer is squeezed and deformed by the closing block 52 and the box 5, so that the space between the closing block 52 and the opening is deformed. The gap is closed.

A moisture-proof layer 51 is bonded in the box body 5. In this embodiment, the moisture-proof layer 51 is an existing waterproof and breathable film. The bottom of the box body 5 is provided with a discharge port, which is communicated with the NaCl inlet pipe. The wall slopes downward and towards the discharge opening. A rotary valve 53 is arranged on the NaCl inlet pipe, and the model is: Y801-4.

The specific implementation process is as follows:

Initially, the rotary valve 53 is closed, and a sufficient amount of NaCl solid particles is fed into the box 5 , and then the closing block 52 is inserted into the opening to seal the box 5 .

When the NaCl solid particles need to be released, the rotary valve 53 is opened, and the NaCl solid particles enter the thickening tower 3 through the NaCl inlet pipe, and then the rotary valve 53 is closed to stop releasing the NaCl solid particles. The NaCl solid particles are supplied to the enrichment tower 3 through a feeder, so that the concentration of the NaCl solution in the enrichment tower 3 can be easily increased.

The above are only the preferred embodiments of the present utility model. It should be pointed out that for those skilled in the art, some modifications and improvements can be made without departing from the concept of the present utility model. These should also be regarded as the present utility model. The scope of protection of the new model will not affect the effect of the implementation of the present utility model and the practicability of the patent. The technologies, shapes and structural parts that are omitted from the description of the present invention are all known technologies.

Claims (10)

1. The utility model provides a salt cooling device of acetylene polymerization reaction gas which characterized in that: the device comprises a salt cooling tower, wherein the top of the salt cooling tower is communicated with a reaction gas exhaust pipe, a wire mesh demister positioned in the salt cooling tower is arranged below the reaction gas exhaust pipe, and the lower part of the salt cooling tower is communicated with a reaction gas inlet pipe;

a thickening tower is arranged below the salt cooling tower, the lower part of the thickening tower is communicated with the bottom of the salt cooling tower, the top of the thickening tower is communicated with a NaCl inlet pipe, and the lower part of the thickening tower is communicated with a pump assembly;

the bottom of the cooler is communicated with the pump assembly, and the top of the cooler is communicated with a cooling pipe communicated with the upper part of the salt cooling tower.

2. The salt cooling device of acetylene polymerization reaction gas according to claim 1, characterized in that: the lower part of the salt cooling tower is communicated with a CH phase liquid discharge pipe positioned below the reaction gas inlet pipe.

3. The salt cooling device of acetylene polymerization reaction gas according to claim 1, characterized in that: the aperture of the silk screen demister is 3-5 um.

4. The salt cooling device of acetylene polymerization reaction gas according to any one of claims 1 to 3, characterized in that: a plurality of uniformly distributed tower plates or fillers are arranged in the salt cooling tower along the axial direction of the salt cooling tower, and the fillers or the tower plates are positioned below the wire mesh demister.

5. The salt cooling device of acetylene polymerization reaction gas according to claim 4, characterized in that: the absorption tower is communicated with the reaction exhaust pipe.

6. The salt cooling device of acetylene polymerization reaction gas according to claim 5, characterized in that: and a heat insulation layer is arranged outside the cooling pipe.

7. The salt cooling device of acetylene polymerization reaction gas according to claim 6, characterized in that: also comprises a supply device which is communicated with the NaCl inlet pipe.

8. The salt cooling device of acetylene polymerization reaction gas according to claim 7, characterized in that: the supply device comprises a box body with an opening arranged on the upper part, a sealing block with a sealing opening arranged on the opening, a discharge opening communicated with a NaCl inlet pipe arranged at the bottom of the box body, and a rotary valve arranged on the NaCl inlet pipe.

9. The salt cooling device of acetylene polymerization reaction gas according to claim 8, characterized in that: the inner wall of the box body is provided with a moisture-proof layer.

10. The salt cooling device of acetylene polymerization reaction gas according to claim 2, characterized in that: and the CH phase liquid discharge pipe is communicated with a phase splitter.

Images