Crude polyether polyol purification system
By designing a purification system including water washing, phase separation and flash evaporation units, and using fiber filters for droplet multiplication technology, the problems of high energy consumption of the flash evaporation device and difficulty in detecting indicators during the polyether polyol purification process are solved, achieving Efficient moisture and salt separation, saving energy consumption and reducing rework.
Patent Information
- Application Number
- CN202420390504.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-03-01
- Publication Date
- 2025-01-24
- Estimated Expiration
- 2034-03-01
AI Technical Summary
In the purification process of polyether polyols, the flash evaporation device has a large processing volume, high energy consumption, and process indicators are not easy to detect, so the product indicators cannot be accurately controlled, resulting in unqualified products need to be reworked, increasing process steps and energy consumption.
Design a purification system of a rough polyether polyol, including water washing units, phase separation units, and flashing units. The phase separation unit adopts a fibrous filter, which is multiplied by dripping technology to separate the water and salt in the coarse polyether polyol after washing the salted water to reduce the burden on the subsequent flashing system.
The efficient separation of moisture and salt is achieved, saving the overall investment and operating energy consumption of the flashing system, and can intuitively detect the indicators of the product after separation of the phase, reducing the generation and rework of unqualified products.
Smart Images
Figure CN222384189U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of polyether polyol production, in particular to a purification system for crude polyether polyol. Background Art
[0002] In the production process of polyether polyols, the crude polyether polyols synthesized by the reaction need to be purified to obtain refined polyether polyols. The conventional treatment method is to wash the salt in the crude polyether polyols with desalted water, wash the salt in the crude polyether polyols into desalted water, and then remove the water in the crude polyether polyols by flash evaporation while taking out the salt in the crude polyether polyols, thereby obtaining refined polyether polyols. This treatment method not only has a large processing capacity and high energy consumption in the flash evaporation device, which is not conducive to the control of production costs, but also the process indicators are not easy to detect and the product indicators cannot be accurately controlled. If the product indicators are unqualified, it is necessary to return to the desalted water washing section, re-wash the salt in the crude polyether polyols, and then enter the flash evaporation. Utility Model Content
[0003] In view of the above technical problems, the purpose of the utility model is to provide a purification system for crude polyether polyols, which rationally applies phase separation technology to the salt separation condition of crude polyether polyols, and achieves good separation effect. It not only removes water from the crude polyether polyols after washing with desalted water, but also removes the salt in the crude polyether polyols, saving the overall investment and operating energy consumption of the subsequent flash evaporation system, and can intuitively detect the salt ions in the polyether polyol phase and the water phase after phase separation, avoiding the increase in process steps and energy consumption caused by rework.
[0004] In order to achieve the above purpose, the technical solution adopted by the utility model is as follows:
[0005] A crude polyether polyol purification system comprises a water washing unit, a phase separation unit and a flash evaporation unit connected in sequence by pipelines.
[0006] The water washing unit is used to wash the salt in the crude polyether polyol into desalted water;
[0007] The phase separation unit is used to remove water and salt from the crude polyether polyol washed with desalted water;
[0008] The flash unit is used to further remove water from the crude polyether polyol to obtain refined polyether polyol.
[0009] In some technical solutions, a fiber filter is installed inside the phase separation unit, and the fiber filter is woven with fiber felt with a diameter less than 200 um.
[0010] In some technical solutions, a sampling valve is arranged at the material outlet and / or water outlet of the phase separation unit.
[0011] In some technical solutions, the water washing unit includes a water washing tank, a first inlet of the water washing tank is connected to a feed pipe, a second inlet of the water washing tank is connected to a water inlet pipe, and a stirring device for evenly mixing crude polyether polyol and desalted water is arranged inside the water washing tank.
[0012] In some technical solutions, the phase separation unit includes a phase separator, the inlet of the phase separator is connected to the outlet of the water washing tank, and the outlet of the phase separator is connected to a salt-containing desalted water outlet pipe.
[0013] In some technical solutions, the flash unit includes a flash tank, the inlet of the flash tank is connected to another outlet of the phase separator, the first outlet of the flash tank is connected to a refined polyether polyol outlet pipe, and the other outlet is connected to a steam condensate outlet pipe.
[0014] In some technical solutions, the phase separator is a horizontal container.
[0015] In some technical solutions, the upper outlet of the phase separator is connected to the inlet of the flash tank, and the lower outlet of the phase separator is connected to the outside of the purification system.
[0016] The utility model adopts the above technical solution to have at least the following beneficial effects:
[0017] The utility model provides a crude polyether polyol purification system. According to the characteristics of the crude polyether polyol, the system is combined with the droplet multiplication technology, and a phase separator is reasonably applied to the salt separation condition of the crude polyether polyol, achieving a good separation effect. It not only removes the water in the crude polyether polyol after washing with desalted water, but also takes out the salt in the crude polyether polyol. The salt separation of the phase separator has the following advantages over the traditional treatment method: 1. It can fully remove the water in the crude polyether polyol, saving the overall investment and operating energy consumption of the subsequent flash evaporation system; 2. The process indicators are easy to monitor, and the salt ions in the polyether polyol phase and the water phase of the phase separator can be intuitively detected to reduce the generation of unqualified products; 3. The phase separator is a static device and will not increase the operating energy consumption. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings and their marks required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.
[0019] Figure 1 It is a schematic structural diagram of a crude polyether polyol purification system described in a specific embodiment of the utility model.
[0020] The meanings of the symbols in the figure are as follows:
[0021] 110—feed pipe, 111—water inlet pipe, 112—water washing tank, 113—first transfer pipe;
[0022] 114—phase separator, 115—second material transfer pipe, 116—salt-containing desalted water outlet pipe;
[0023] 117—flash tank, 118—steam condensate outlet pipe, 119—fine polyether polyol outlet pipe. DETAILED DESCRIPTION
[0024] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the specific implementation methods of the utility model will be described below with reference to the accompanying drawings. Obviously, the accompanying drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings and other implementation methods can be obtained based on these drawings without creative work.
[0025] In order to simplify the drawings, only the parts related to the utility model are schematically shown in each figure, and they do not represent the actual structure of the product. In addition, in order to simplify the drawings and facilitate understanding, in some figures, only one of the parts with the same structure or function is schematically drawn or marked. In this article, "one" not only means "only one", but also means "more than one".
[0026] It should be further understood that the term “and / or” used in the specification and appended claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes these combinations.
[0027] In this article, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this utility model can be understood according to specific circumstances.
[0028] In addition, in the description of the present application, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.
[0029] In one embodiment, a purification system for crude polyether polyol is provided, see Figure 1The purification system comprises a water washing unit, a phase separation unit and a flash evaporation unit which are connected in sequence by pipelines, wherein the water washing unit is used to wash the salt in the crude polyether polyol into desalted water; the phase separation unit is used to remove the water in the crude polyether polyol washed with desalted water and take out the salt at the same time; the flash evaporation unit is used to further remove the water in the crude polyether polyol to obtain refined polyether polyol.
[0030] In the above embodiment, the water washing unit includes a water washing tank 112, and the first inlet of the water washing tank 112 is connected to a feed pipe 110 for inputting a crude polyether polyol material synthesized by reaction in the polyether polyol production process into the water washing tank 112; the second inlet of the water washing tank 112 is connected to a water inlet pipe 111 for inputting desalted water into the water washing tank 112; an agitator is arranged inside the water washing tank 112 for making the crude polyether polyol fully contact with the desalted water and transferring the salt in the crude polyether polyol into the desalted water; the outlet of the water washing tank 112 is also connected to a first material transfer pipe 113 for outputting the mixed material after washing to the downstream.
[0031] In the above embodiment, the phase separation unit includes a phase separator 114, the inlet of the phase separator 114 is connected to the outlet of the first transfer pipe 113, the first outlet of the phase separator 114 is connected to the second transfer pipe 115 for outputting the polyether polyol material after phase separation to the downstream, and the second outlet is connected to the salt-containing desalted water outlet pipe 116.
[0032] In a preferred embodiment, a fiber filter is installed inside the phase separation unit. The fiber filter is woven with fiber felt with a diameter of less than 200um. The ultrafine fiber felt has super hydrophobicity and oleophobicity. When water droplets and oil droplets pass through the fiber felt, due to the capture, collision and rebound effect of the fiber felt, the water droplets and oil droplets continue to grow in the process of passing through the fiber felt, and finally the separation of polyether polyol and salt-containing desalted water is achieved; specifically, the fiber felt is not limited to metal or non-metallic materials.
[0033] In some specific embodiments, the phase separator 114 is a horizontal container, the upper outlet of the phase separator 114 is connected to the flash unit, and the lower outlet of the phase separator 114 is connected to the outside of the purification system.
[0034] In the application of the phase separator in the crude polyether polyol salt separation process in the present embodiment, not only the salt in the crude polyether polyol but also the water in the crude polyether polyol are taken out, thereby reducing the processing capacity of the subsequent flash evaporation device, and reducing the energy consumption of the equipment and the production investment cost.
[0035] In another preferred embodiment, a sampling valve is installed at the inlet end of the second material transfer pipe 115 connected to the outlet of the phase separator 114 and the salt-containing desalted water outlet pipe 116.
[0036] In this embodiment, the crude polyether polyol and the salt-containing desalted water separated by the phase separator can be sampled and tested through the sampling valve to quickly determine the water washing effect and reduce the occurrence of unqualified polyether polyol being returned for re-washing.
[0037] In the above embodiment, the flash unit includes a flash tank 117, the inlet of the flash tank 117 is connected to the outlet of the second transfer pipe 115, the first outlet of the flash tank 117 is connected to the refined polyether polyol outlet pipe 119, and the other outlet is connected to the steam condensate outlet pipe 118.
[0038] See also Figure 1 , the process flow of this application is described in detail below:
[0039] The crude polyether polyol enters the water washing tank 112 through the feed pipe 110, the agitator in the water washing tank 112 is turned on, and a proper amount of desalted water is introduced through the water inlet pipe 111 to allow the crude polyether polyol to fully contact with the desalted water, and the salt in the crude polyether polyol is transferred into the desalted water.
[0040] The crude polyether polyol after washing enters the phase separator 114 through the first transfer pipe 113. Under the action of the phase separator 114, the crude polyether polyol and the saline desalted water are separated. The crude polyether polyol discharged from the upper part of the phase separator 114 enters the flash tank 117 through the second transfer pipe 115; the saline desalted water discharged from the lower part of the phase separator 114 is discharged into the discharge system.
[0041] The crude polyether polyol is further dehydrated in a flash tank to obtain qualified refined polyether polyol and steam condensed water generated by flash evaporation.
[0042] In order to have a more accurate understanding of the technical solution and technical effects of the present application, a specific example is provided as follows:
[0043] After the crude polyether polyol is washed with desalted water, it contains 1.6‰ potassium dihydrogen phosphate and 5.8% water; after being transported to the phase separator 114 through a pipeline and separated by the phase separator 114, the polyether polyol coming out of the upper part of the phase separator 114 contains less than 3ppm potassium dihydrogen phosphate and less than 3% water; the salt-containing desalted water coming out of the lower part of the phase separator 114 contains less than 50ppm polyether polyol. During the operation, a sample is taken from the upper outlet of the phase separator 114 to detect the content of potassium dihydrogen phosphate in the polyether polyol. When the content of potassium dihydrogen phosphate is less than 3ppm, the final refined polyether polyol product is qualified.
[0044] The successful operation of this device not only facilitates sampling and testing, and reduces the number of reworks of defective products; it also reduces the processing volume of the flash evaporation device by more than 43%.
[0045] The above-mentioned embodiments only express several implementation methods of the utility model, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the patent of the utility model. It should be pointed out that, for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the utility model, and these all belong to the protection scope of the utility model. Therefore, the protection scope of the utility model shall be based on the attached claims.
Claims
1. A crude polyether polyol purification system, characterized in that: It includes a water washing unit, a phase separation unit and a flash unit connected in sequence by pipelines, The water washing unit is used to wash the salt in the crude polyether polyol into desalted water; The phase separation unit is used to remove water and salt from the crude polyether polyol washed with desalted water; The flash unit is used to further remove water from the crude polyether polyol to obtain refined polyether polyol.
2. The crude polyether polyol purification system according to claim 1, characterized in that: A fiber filter is installed inside the phase separation unit, and the fiber filter is woven with fiber felt with a diameter less than 200um.
3. The crude polyether polyol purification system according to claim 1, characterized in that: The material outlet and / or water outlet of the phase separation unit is arranged with a sampling valve.
4. The crude polyether polyol purification system according to any one of claims 1 to 3, characterized in that: The water washing unit comprises a water washing tank, a first inlet of the water washing tank is connected to a feed pipe, a second inlet of the water washing tank is connected to a water inlet pipe, and a stirring device for uniformly mixing crude polyether polyol and desalted water is arranged inside the water washing tank.
5. The crude polyether polyol purification system according to claim 4, characterized in that: The phase separation unit comprises a phase separator, the inlet of the phase separator is communicated with the outlet of the water washing tank, and the outlet of the phase separator is communicated with a salt-containing desalted water outlet pipe.
6. The crude polyether polyol purification system according to claim 5, characterized in that: The flash unit comprises a flash tank, the inlet of the flash tank is connected to another outlet of the phase separator, the first outlet of the flash tank is connected to a refined polyether polyol outlet pipe, and the other outlet is connected to a steam condensate outlet pipe.
7. The crude polyether polyol purification system according to claim 6, characterized in that: The phase separator is a horizontal container.
8. The crude polyether polyol purification system according to claim 7, characterized in that: The upper outlet of the phase separator is communicated with the inlet of the flash tank, and the lower outlet of the phase separator is communicated to the outside of the purification system.