Polyether polyol synthesizer
By integrating a Venturi-based mixing reactor into the polyether polyol synthesis unit, the problem of excessive pressure inside the reactor was solved, achieving more efficient production and safety, and simplifying the modification process.
Patent Information
- Application Number
- CN202520200201.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-09
- Publication Date
- 2026-02-27
- Estimated Expiration
- 2035-02-09
AI Technical Summary
In existing polyether polyol synthesis equipment, the reaction between potassium alkoxide and epoxide is difficult, leading to gasification, excessive pressure inside the reactor, safety hazards, and low production efficiency.
Integrating a mixing reactor based on the Venturi principle into the reaction vessel system promotes the mixing of liquid and gas through forced circulation and negative pressure intake, thereby improving the mixing and contact efficiency of gaseous epoxy compounds and liquid initiators.
It significantly shortens the reaction time, improves production efficiency, reduces the pressure inside the reactor, enhances safety, reduces the risk of shutdown, and the device has a simple structure that is easy to modify.
Smart Images
Figure CN223945658U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to the field of chemical production equipment, concretely relates to a polyether polyol synthesis device, especially to a mixed reactor integrated in a reaction kettle system, which improves gas-liquid mixing efficiency, promotes the mixing reaction of liquid starter and gaseous epoxide compound, and improves reaction efficiency and safety. BACKGROUND
[0002] Polyether polyol is an organic polymer, which is prepared by initiation reaction, polyaddition reaction and curing reaction of starter (compound containing active hydrogen group), such as sorbitol, glycerol, propylene glycol, diethylene glycol, and ethylene oxide (EO), propylene oxide (PO) and butylene oxide (BO) in the presence of catalyst. The largest polyether production is glycerol (glycerol) as a starter and epoxide (usually PO and EO), which produces various general polyether polyols by changing the feeding mode (mixed or separate), the ratio of the amount, the feeding sequence and other conditions. The polyether polyol series products are mainly used for preparing hard polyurethane foam plastic, and are widely used in the fields of refrigerator, freezer, refrigerated truck, heat insulation plate, pipeline insulation and the like.
[0003] At present, the commonly used catalysts for polyether polyol are potassium hydroxide, bimetallic catalyst and phosphine catalyst. The bimetallic catalyst and phosphine catalyst cannot be used in the polymerization reaction of small molecule starter, and potassium hydroxide can be used as a catalyst for polymerization reaction of small molecule starter. First, potassium hydroxide and small molecule starter are prepared into potassium alcohol by vacuum dehydration, and then the potassium alcohol and epoxide compound are polymerized to prepare polyether polyol. However, there is difficulty in initiation reaction in the reaction process of potassium alcohol and epoxide compound, which causes the epoxide compound to be gasified in the reaction kettle, reduces the contact efficiency of the starter and the epoxide compound, and causes the pressure in the reaction kettle to be too high, which has safety hidden danger. In view of the above problems, most enterprises choose to reduce the feeding speed of epoxide compound and prolong the process operation time of initiation reaction for production, but the above process operation has the problems of low efficiency, energy waste and poor economic benefit. Therefore, it is urgent to develop a polyether polyol synthesis device which can strengthen gas-liquid mixing, reduce reaction pressure and improve production efficiency. UTILITY MODEL CONTENT
[0004] In view of the deficiencies of the prior art, the utility model provides a polyether polyol synthesis device, which has the advantages of improving reaction efficiency, reducing reaction kettle pressure in synthesis process, and being safe to use, solves the safety hidden danger caused by high pressure in the reaction kettle due to slow initiation reaction speed of the traditional synthesis device, and solves the problem of low production efficiency.
[0005] To achieve the above objectives, this utility model provides the following technical solution: a polyether polyol synthesis apparatus, comprising: a vessel body; a motor installed above the vessel body; a stirring shaft connected to the motor and extending into the vessel body; a stirring paddle installed at the bottom of the stirring shaft; a liquid raw material feed line located at the top of one side of the vessel body; a reactor outlet located at the bottom of the vessel body; a circulating pump whose inlet is connected to the reactor outlet; a mixing reactor with a mixing reactor inlet at its top, the outlet of the circulating pump connected to the mixing reactor inlet; a mixing reactor outlet located at the bottom of the mixing reactor, the mixing reactor outlet connected to the vessel body; a gas phase pipe connected to the vessel body; an air inlet located on the side of the mixing reactor, the gas phase pipe connected to the air inlet; and a feed pipe inserted into the mixing reactor, with the outlet height of the feed pipe lower than the horizontal height of the air inlet.
[0006] Furthermore, the liquid feed line is used to add at least one liquid feedstock selected from sorbitol, glycerol, propylene glycol, diethylene glycol, ethylene oxide, or propylene oxide.
[0007] Furthermore, valves are provided at the discharge port of the reactor, the discharge port of the mixing reactor, and the gas phase pipe; the valves are in the open state during the initiation of the reaction and the synthesis process, and in the closed state during the ripening process;
[0008] Furthermore, the mixing reactor is a tubular reactor designed according to the Venturi principle, and the gas phase pipe is used to introduce the gas phase material in the vessel into the mixing reactor.
[0009] Furthermore, the arrangement of the top feed inlet, bottom discharge outlet, and side air inlet of the mixing reactor is used to promote the mixing reaction of liquid and gas.
[0010] Compared with the prior art, the technical solution of this application has the following beneficial effects: (1) By adding a mixing reactor based on the Venturi principle, forced circulation and negative pressure suction are formed in the system, which greatly enhances the mixing contact between gaseous epoxy compounds and liquid initiators, making the initiation reaction faster and more thorough; (2) The pressure of the reaction system in the initiation and polymerization stages is effectively reduced, the safety of the production process is improved, and the risk of shutdown due to overpressure is reduced; (3) There is no need to deliberately reduce the feeding speed of epoxy compounds, which significantly shortens the total reaction time and improves equipment utilization and production efficiency; (4) The device structure is relatively simple, easy to modify and implement on the basis of existing reactors, and has strong applicability. Attached Figure Description
[0011] Figure 1 This is a schematic diagram of the overall structure of this utility model.
[0012] In the figure: 1, motor; 2, liquid raw material feeding pipeline; 3, stirring shaft; 4, kettle body; 5, stirring paddle; 6, reaction kettle discharge port; 7, mixed reactor feeding port; 8, mixed reactor; 9, feeding pipe; 10, mixed reactor discharge port; 11, gas phase port; 12, gas phase pipe; 13, circulating pump. DETAILED DESCRIPTION
[0013] The process steps for synthesizing polyether polyol using the device in Example 1 are as follows:
[0014] Feeding: 460 g of sorbitol, 160 g of glycerol, and 9 g of potassium hydroxide were fed into the reaction kettle, and the reaction kettle was subjected to nitrogen leak testing and replacement.
[0015] Preparation of potassium alcoholate: after nitrogen replacement was completed, the temperature was raised to 105°C, and potassium alcoholate was prepared under the condition of -0.095 Mpa for 2 hours.
[0016] Initiation of reaction: the temperature was lowered to 85°C, and the propylene oxide feeding was started, the reaction kettle pressure was maintained at 0.25 Mpa during the feeding process, the feeding time was 1 hour, and the reaction kettle discharge port valve, the mixed reactor discharge port valve, and the reaction kettle gas phase pipe valve were kept in the open state during the whole initiation of reaction, and the circulating pump was in the open state.
[0017] Polymerization reaction: after the initiation of reaction was completed, the material was heated to 110°C, and the propylene oxide feeding was started, the reaction kettle pressure was maintained at 0.25 Mpa, and the feeding time was 6 hours, and the reaction kettle discharge port valve, the mixed reactor discharge port valve, and the reaction kettle gas phase pipe valve were kept in the open state during the whole polymerization reaction, and the circulating pump was in the open state.
[0018] Curing reaction: after the polymerization reaction was completed, the material was heated to 120°C for 2 hours, and the reaction kettle discharge port valve, the mixed reactor discharge port valve, and the reaction kettle gas phase pipe valve were closed, and the circulating pump was turned off.
[0019] Post-treatment: after the curing, the material was treated by adding phosphoric acid for neutralization, adding adsorbent for adsorbing potassium dihydrogen phosphate salt, and then subjected to filtration and drying to obtain polyether polyol.
[0020] Comparative Example 1
[0021] Feeding: 460 g of sorbitol, 160 g of glycerol, and 9 g of potassium hydroxide were fed into the reaction kettle, and the reaction kettle was subjected to nitrogen leak testing and replacement.
[0022] Preparation of potassium alcoholate: after nitrogen replacement was completed, the temperature was raised to 105°C, and potassium alcoholate was prepared under the condition of -0.095 Mpa for 2 hours.
[0023] Initiation of reaction: the temperature was lowered to 85°C, and the propylene oxide feeding was started, the reaction kettle pressure was maintained at 0.25 Mpa during the feeding process, the feeding time was 1.5 hours.
[0024] Polymerization reaction: after the initiation reaction is finished, the material is heated to 110 DEG C, then the propylene oxide is added, the pressure of the reaction kettle is maintained at 0.25 Mpa, and the feeding time is 7.5 hours.
[0025] Curing reaction: after the polymerization reaction is finished, the material is heated to 120 DEG C for curing for 2 hours.
[0026] Post-treatment: after the material after curing is treated by adding phosphoric acid for neutralization, adding adsorbent for adsorbing potassium dihydrogen phosphate salt, filtering and drying, the polyether polyol is obtained.
[0027] As shown by the examples and the comparative examples, the time for synthesizing the polyether polyol by using the device is shortened from 9 hours of the traditional synthesis kettle to 7 hours, and the synthesis efficiency is improved by 22%.
Claims
1. A polyether polyol synthesis apparatus, characterized by, It includes: The kettle body (4); motor (1), installed on the kettle body (4) above; stirring shaft (3), connected with the motor (1) and extends into the kettle body (4) inside; stirring paddle (5), installed at the bottom of the stirring shaft (3); liquid raw material feeding pipeline (2), provided on the top of one side of the kettle body (4); reactor discharge port (6), provided at the bottom of the kettle body (4); circulating pump (13), its inlet is connected with the reactor discharge port (6); mixed reactor (8), its top is provided with mixed reactor inlet (7), the outlet of the circulating pump (13) is connected with the mixed reactor inlet (7) of the mixed reactor (8); the bottom of the mixed reactor (8) is provided with mixed reactor outlet (10), the mixed reactor outlet (10) is connected with the kettle body (4); gas phase pipe (12), connected with the kettle body (4); gas inlet (11), provided on the side of the mixed reactor (8), the gas phase pipe (12) is connected with the gas inlet (11); feed pipe (9), inserted into the mixed reactor (8) inside, and the outlet height of the feed pipe (9) is lower than the horizontal height of the gas inlet (11).
2. The polyether polyol synthesis apparatus of claim 1, wherein, The liquid raw material feeding pipeline (2) is used for adding at least one liquid raw material of sorbitol, glycerol, propylene glycol, diethylene glycol, ethylene oxide or propylene oxide.
3. The polyether polyol synthesis apparatus of claim 1, wherein, The reactor discharge port (6), the mixed reactor outlet (10) and the gas phase pipe (12) are all provided with valves; the valves are in the open state during the initiation of reaction and synthesis process, and in the closed state during the curing process.
4. The polyether polyol synthesis apparatus of claim 1, wherein, The mixed reactor (8) is a tubular reactor designed according to the Venturi principle, and the gas phase pipe (12) is used for guiding the gas phase material in the kettle body (4) into the mixed reactor (8).
5. The polyether polyol synthesis apparatus of claim 1, wherein, The arrangement of the top mixed reactor inlet (7), the bottom mixed reactor outlet (10) and the side gas inlet (11) of the mixed reactor (8) is used to promote the mixing reaction of liquid and gas.