Polymerization system for dehydration condensation reaction

Abstract

The utility model discloses a polymerization system for dehydration condensation reaction, which belongs to the technical field of polymer production and comprises a polymerization reaction kettle, a through hole is arranged at the top of the polymerization reaction kettle, a tower column is vertically arranged on the through hole, the tower column comprises a plurality of tower sections which are sequentially communicated from top to bottom, and fillers are arranged in the tower sections. A tower cap is arranged at the top end of the tower section located at the uppermost end of the tower column, a cooling jacket and a thermometer are arranged on the tower cap, a gas phase outlet is formed in the upper portion of the tower cap and connected with a water removal tank, a gas outlet in the top of the water removal tank is connected with a recovery device, and a vacuum pump is connected to the tail end of the recovery device in the running direction of the recovery device; the vacuum pump is connected with a PLC. By utilizing the tower column, a solvent and a monomer with high boiling points are condensed, and water and impurities with lower boiling points leave the tower column, so that the raw material waste is reduced while the reaction is promoted; a water removal tank is arranged to absorb moisture in gas, so that the moisture in the gas is prevented from condensing when residual solvents and monomers are condensed in the recovery device, and the separation effect is not influenced.

Description

Technical Field

[0001] This utility model relates to the field of polymer production technology, and specifically to a polymerization system for dehydration condensation reaction. Background Technology

[0002] The synthesis of new polysulfone and polyketone materials by dehydration condensation reaction generally involves high-temperature stepwise polymerization. The water produced in the reaction can inhibit the polymerization reaction, affect the reaction rate, or even stop the reaction.

[0003] Currently, dehydration methods include azeotropic dehydration with dehydrating agents and distillation. Azeotropic dehydration with dehydrating agents can remove most of the water from the reaction system, but it is time-consuming and introduces new solvents. In addition to introducing VOCs pollution, it will also leave residues in the product, affecting product quality.

[0004] Distillation to remove water mostly uses a simple high-temperature evaporation method, but many solvents and some monomers will be distilled out along with the water, resulting in waste of raw materials.

[0005] In view of the problems existing in the prior art, this utility model combines years of design and use experience in related fields to design and manufacture a polymerization system for dehydration condensation reaction to overcome the above defects. Utility Model Content

[0006] To address the problems existing in the prior art, this utility model provides a polymerization system for dehydration condensation reaction, which can accelerate the water distillation rate, promote the polymerization reaction to proceed to the right, and avoid introducing impurities, thereby obtaining high-quality polymers.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: a polymerization system for dehydration condensation reaction, comprising a polymerization reactor, a through hole at the top of the polymerization reactor, a column vertically arranged on the through hole, the column comprising several columns connected vertically, packing material inside the columns, a column cap at the top of the column at the uppermost end of the column, a cooling jacket and a thermometer on the column cap, a gas phase outlet at the upper part of the column cap, a dehydration tank connected to the gas phase outlet, a recovery device connected to the outlet of the dehydration tank, and a vacuum pump connected to the end of the recovery device along the running direction of the recovery device;

[0008] The vacuum pump is connected to a PLC.

[0009] Preferably, the dewatering tank is provided with several detachable adsorption layers, which are horizontally distributed and vertically arranged, and each adsorption layer contains a dewatering agent.

[0010] Preferably, the dewatering tank is provided with a tank door, the upper and lower surfaces of the adsorption layer are provided with sliding strips, and the top and bottom of the inner wall of the dewatering tank are provided with several guide rails, and the sliding strips are slidably engaged with the guide rails.

[0011] Preferably, the gas phase outlet is connected to the water removal tank via a gas outlet pipe, and the gas outlet pipe is provided with a heat insulation layer.

[0012] Preferably, the recovery device includes a condenser, the air inlet of which is connected to the air outlet of the dewatering tank, and the outlet of the condenser is connected to a solvent storage tank.

[0013] Preferably, the solvent storage tank has an air outlet at the top and a liquid outlet at the bottom, and the air outlet of the solvent storage tank is connected to a buffer chamber.

[0014] Preferably, the polymerization reactor is provided with a solvent inlet, and the outlet at the bottom of the solvent storage tank is connected to the solvent inlet through a solvent pipe.

[0015] Preferably, the solvent pipeline is equipped with a one-way valve.

[0016] Preferably, it also includes a condensate storage tank and a chilled brine storage tank. The outlet of the condensate storage tank is connected to a first outlet pipe, and the outlet of the chilled brine storage tank is connected to a second outlet pipe. The lower end of the cooling jacket is connected to an inlet pipe, and the first outlet pipe, the second outlet pipe, and the inlet pipe are interconnected by a three-way valve.

[0017] The three-way valve is connected to the PLC.

[0018] The advantages of this utility model are:

[0019] 1. This invention features a column at the top of the polymerization reactor to separate gaseous water, some solvent, and monomer. Most of the solvent and monomer with higher boiling points condense back into the polymerization reactor during the ascent, while water and impurities with lower boiling points leave the column. This promotes the reaction while reducing raw material waste. By absorbing moisture in the gas through a dewatering tank, the moisture in the gas is prevented from condensing along with the residual solvent and monomer in the recovery device, thus avoiding affecting the separation effect.

[0020] 2. This utility model controls the temperature of the tower cap by introducing different media into the cooling jacket through a three-way valve and by controlling the time the vacuum pump is turned on, thereby controlling the gas composition at the gas phase outlet of the tower cap. This avoids the problem of excessively high temperatures carrying away a large amount of solvent and monomers, or excessively low temperatures preventing water from being removed. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of a polymerization system used for dehydration condensation reaction.

[0022] In the diagram: 1-Polymerization reactor, 2-Through hole, 3-Tower section, 4-Tower cap, 5-Water removal tank, 6-Adsorption layer, 7-Gas outlet pipe, 8-Slider, 9-Guide rail, 10-Cooling jacket, 11-Condenser, 12-Solvent storage tank, 13-Buffer chamber, 14-Solvent pipe, 15-Vacuum pump, 16-Three-way valve, 17-Condensate storage tank, 18-Refrigerated brine storage tank. Detailed Implementation

[0023] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to the accompanying drawings.

[0024] like Figure 1 As shown, a polymerization system for dehydration condensation reaction includes a polymerization reactor 1 with a through-hole 2 at the top. A column is vertically mounted on the through-hole 2, and the column includes several column sections 3 connected vertically. The column sections 3 are filled with packing material. A tower cap 4 is located at the top of the uppermost column section 3, and a cooling jacket 10 and a thermometer are mounted on the tower cap 4. A gas phase outlet is located at the upper part of the tower cap 4, and the gas phase outlet is connected to a dehydration tank 5. The gas outlet of the dehydration tank 5 is connected to a recovery device. Along the operating direction of the recovery device, a vacuum pump 15 is connected to the end of the recovery device, and the vacuum pump 15 is connected to a PLC. Specifically, depending on the polymerization reaction, the column diameter is preferably 100-500 mm, and the column height is preferably 0.5-3 meters.

[0025] In this invention, during the polymerization reaction, water, low-boiling-point impurities, some solvent, and some monomer generated during vacuuming evaporate into a gaseous state and enter the column. After passing through several column sections 3 and the column cap 4, most of the higher-boiling-point solvent and monomer condense and flow back into the polymerization reactor 1. Since solvents such as dimethyl sulfoxide and N,N-dimethylformamide are miscible with water, they cannot be separated by liquid-phase separation. A dehydration tank 5 removes water from the remaining gas, thus preventing moisture in the gas from condensing along with the residual solvent and monomer in the recovery device, which would affect the separation effect. Uncondensed low-boiling-point impurities are extracted by a vacuum pump 15. This invention can promptly remove water and low-boiling-point impurities from the reaction system, accelerate the reaction, and improve polymer quality.

[0026] It also includes a condensate storage tank 17 and a chilled brine storage tank 18. The outlet of the condensate storage tank 17 is connected to a first outlet pipe, and the outlet of the chilled brine storage tank 18 is connected to a second outlet pipe. The lower end of the cooling jacket 10 is connected to an inlet pipe. The first outlet pipe, the second outlet pipe, and the inlet pipe are interconnected through a three-way valve 16. The three-way valve 16 is connected to the PLC.

[0027] The PLC controls the connection between the condensate storage tank 17 and the cooling jacket 10 via the three-way valve 16, or between the chilled brine storage tank 18 and the cooling jacket 10, thereby introducing different media into the cooling jacket 10. The PLC also controls the start-up time of the vacuum pump 15, adjusting the vacuum level inside the polymerization reactor 1 and lowering the temperature of the water evaporation. Both of these factors together change the temperature of the tower cap 4, thus controlling the composition of the gas leaving the tower cap 4. This prevents excessively high temperatures from carrying away large amounts of solvent and monomer, and excessively low temperatures from preventing water removal.

[0028] Specifically, the dehydration tank 5 is equipped with several detachable adsorption layers 6, which are horizontally distributed and vertically arranged, each containing a dehydrating agent. The dehydration tank 5 has a door, and sliding strips 8 are provided on the upper and lower surfaces of the adsorption layers 6. Several guide rails 9 are provided at the top and bottom of the inner wall of the dehydration tank 5, with the sliding strips 8 slidingly engaging with the guide rails 9. The inlet and outlet of the dehydration tank 5 are located at opposite ends. Specifically, the gas passes sequentially through multiple adsorption layers 6 in the dehydration tank 5, effectively absorbing moisture from the gas and improving the purity of subsequent residual solvents and monomers. The dehydrating agent is selected based on the specific reaction and can be commonly used dehydrating agents in the field, such as phosphorus pentoxide or anhydrous magnesium sulfate. The adsorption layers 6 are detachable, allowing for timely replacement and preventing failure. The gas phase outlet is connected to the dehydration tank 5 via an outlet pipe 7, which is equipped with an insulation layer. By setting up an insulation layer, heat loss from the gas is reduced, and solvents, monomers, and water are prevented from condensing into liquids in the gas outlet pipe 7.

[0029] The recovery device includes a condenser 11, whose inlet is connected to the outlet of the dehydration tank 5, and whose outlet is connected to a solvent storage tank 12. The solvent storage tank 12 has an outlet at its top and a liquid outlet at its bottom, and the outlet is connected to a buffer chamber 13. The polymerization reactor 1 has a solvent inlet, and the liquid outlet at the bottom of the solvent storage tank 12 is connected to the solvent inlet via a solvent pipe 14. A one-way valve is installed on the solvent pipe 14.

[0030] In this invention, the gas after moisture absorption still contains a small amount of solvent, monomer, and low-boiling-point impurities. The solvent and monomer are condensed into liquid by the condenser 11 and remain in the solvent storage tank 12, then returned to the polymerization reactor 1 via the solvent pipeline 14 to avoid waste. The low-boiling-point impurities are extracted by the vacuum pump 15 and can be treated in the exhaust gas treatment system. A buffer chamber 13 is provided to prevent backflow when the vacuum pump 15 stops.

[0031] Detailed operation process

[0032] After the reactants react in polymerization reactor 1 for a period of time, a gaseous mixture (including water, solvent, monomer, and low-boiling-point impurities) is generated at the top of reactor 1. The connection between the condensate storage tank 17 and the cooling jacket 10 is opened via the three-way valve 16, allowing condensate to flow into the cooling jacket 10. The vacuum pump 15 is then turned on, controlling the vacuum level of the reaction system to 0.1 MPa. The gaseous mixture enters the column through through-hole 2. During its ascent, most of the high-boiling-point solvent and monomer condense and return to polymerization reactor 1.

[0033] The remaining gaseous mixture exits from the gas phase outlet of tower cap 4, passes through dehydration tank 5 to remove water, and then enters condenser 11. Residual solvent and monomer in the gaseous mixture are condensed into liquid by condenser 11 and flow into solvent storage tank 12. Low-boiling-point impurities exit from the outlet of solvent storage tank 12, enter buffer chamber 13, and then proceed to the subsequent tail gas treatment system for processing. Then, the one-way valve is opened, and the condensed solvent and monomer return to polymerization reactor 1 through solvent pipeline 14, where the monomer continues to participate in the reaction.

[0034] It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of protection of this utility model. Furthermore, it should be understood that after reading the technical description of this utility model, those skilled in the art can make various alterations, modifications, and / or variations to this utility model, and all such equivalent forms also fall within the scope of protection defined by the appended claims.

Claims

1. A polymerization system for dehydration condensation reactions, characterized in that, The reactor includes a polymerization reactor (1), which has a through hole (2) at the top. A column is vertically installed on the through hole (2). The column includes several columns (3) that are connected vertically. The column is filled with packing material. A tower cap (4) is installed at the top of the column (3) at the top of the column. A cooling jacket (10) and a thermometer are installed on the tower cap (4). A gas phase outlet is provided at the top of the tower cap (4). A water removal tank (5) is connected to the gas outlet. A recovery device is connected to the outlet of the water removal tank (5). A vacuum pump (15) is connected to the end of the recovery device along the running direction of the recovery device. The vacuum pump (15) is connected to a PLC.

2. The polymerization system for dehydration condensation reaction according to claim 1, characterized in that, The dewatering tank (5) is provided with several layers of adsorption layers (6) that can be detached. The layers of adsorption layers (6) are horizontally distributed and vertically arranged. The adsorption layers (6) contain a dewatering agent.

3. The polymerization system for dehydration condensation reaction according to claim 2, characterized in that, The dewatering tank (5) is provided with a tank door, and the upper and lower surfaces of the adsorption layer (6) are provided with slide bars (8). The top and bottom of the inner wall of the dewatering tank (5) are provided with several guide rails (9), and the slide bars (8) and the guide rails (9) slide in cooperation.

4. The polymerization system for dehydration condensation reaction according to claim 1, characterized in that, The gas phase outlet is connected to the water removal tank (5) through a gas outlet pipe (7), and the gas outlet pipe (7) is provided with a heat insulation layer.

5. A polymerization system for dehydration condensation reaction according to claim 1, characterized in that, The recovery device includes a condenser (11), the air inlet of which is connected to the air outlet of the dewatering tank (5), and the outlet of the condenser (11) is connected to a solvent storage tank (12).

6. A polymerization system for dehydration condensation reaction according to claim 5, characterized in that, The solvent storage tank (12) has an air outlet at the top and a liquid outlet at the bottom. The air outlet of the solvent storage tank (12) is connected to a buffer chamber (13).

7. A polymerization system for dehydration condensation reaction according to claim 6, characterized in that, The polymerization reactor (1) is provided with a solvent inlet, and the outlet at the bottom of the solvent storage tank (12) is connected to the solvent inlet through a solvent pipe (14).

8. A polymerization system for dehydration condensation reaction according to claim 7, characterized in that, A one-way valve is provided on the solvent pipeline (14).

9. A polymerization system for dehydration condensation reaction according to claim 1, characterized in that, It also includes a condensate storage tank (17) and a chilled brine storage tank (18). The outlet of the condensate storage tank (17) is connected to a first outlet pipe, and the outlet of the chilled brine storage tank (18) is connected to a second outlet pipe. The lower end of the cooling jacket (10) is connected to an inlet pipe. The first outlet pipe, the second outlet pipe and the inlet pipe are interconnected by a three-way valve (16). The three-way valve (16) is connected to the PLC.

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