A light component separation and extraction device for methanol rectification pretreatment

Abstract

The utility model relates to rectification pretreatment technical field, solved the problem that light component impurity is difficult to separate in the methanol rectification pretreatment process, specifically discloses a kind of light component separation and extraction device for methanol rectification pretreatment, including water cooling mechanism and static separation tank, the outlet end of water cooling mechanism is connected with the inlet end of static separation tank, backflow outlet end and recovery outlet end are provided on static separation tank, backflow outlet end and the inlet end of water cooling mechanism are connected by valve;Wherein, static separation tank is sequentially provided with the separation chamber, overflow chamber and recovery chamber that intercommunication, the separation chamber is communicated with backflow outlet end, the recovery chamber is communicated with recovery outlet end, the overflow chamber is arranged between separation chamber and recovery chamber.The utility model is used in the methanol rectification pretreatment process, the light component in it can be separated and extracted, with the effect that light component can be effectively separated while ensuring methanol recovery rate and purity.

Description

Technical Field

[0001] This utility model relates to the field of distillation pretreatment technology, and in particular to a device for separating and extracting light components in methanol distillation pretreatment. Background Technology

[0002] In methanol production, crude methanol typically contains various impurities, including low-boiling-point light components (such as dimethyl ether, methyl formate, acetaldehyde, etc.) and high-boiling-point heavy components (such as ethanol, water, higher alcohols, etc.). Removing these impurities is a crucial step in the methanol distillation process, directly affecting the purity and quality of the final product. Currently, the industrial practice commonly employs a two-tower distillation process, consisting of a pre-distillation column and a main distillation column, to purify methanol. The pre-distillation column primarily removes low-boiling-point light components, while the main distillation column further purifies the methanol and removes high-boiling-point impurities.

[0003] However, the relevant process has the following problems in actual operation: Because the boiling points of light components such as dimethyl ether (boiling point 24.82℃), methyl formate (boiling point 31.5℃), and acetaldehyde (boiling point 20.8℃) are much lower than those of methanol (boiling point 64.7℃), some light components fail to completely vaporize during the condensation process at the top of the pre-distillation column. Instead, they condense together with methanol and flow back into the column, resulting in residual light components in the subsequent main column product, affecting methanol purity. Increasing the condensation temperature (e.g., >40℃) to enhance the vaporization of light components can reduce the reflux of light components, but it also causes some methanol to be emitted with the non-condensable gas, resulting in a decrease in methanol yield and increased production costs. Utility Model Content

[0004] To address the problem of difficulty in separating light component impurities during methanol distillation pretreatment in existing technologies, this invention provides a device for separating and extracting light components during methanol distillation pretreatment.

[0005] The technical solution adopted in this utility model is: A device for separating and extracting light components in methanol distillation pretreatment includes a water cooling mechanism and a static separation tank. The outlet end of the water cooling mechanism is connected to the inlet end of the static separation tank. The static separation tank is provided with a reflux outlet end and a recovery outlet end. The reflux outlet end is connected to the inlet end of the water cooling mechanism through a valve. The static separation tank is provided with a separation chamber, an overflow chamber and a recovery chamber that are interconnected. The separation chamber is connected to the reflux outlet, the recovery chamber is connected to the recovery outlet, and the overflow chamber is located between the separation chamber and the recovery chamber. The separation chamber is used to separate impurities and methanol and to transport methanol back to the water cooling mechanism through a valve from the reflux outlet. The overflow chamber is used to collect impurities overflowing from the separation chamber. The recovery chamber is used to discharge the impurities transported from the overflow chamber to the external recovery system from the recovery outlet.

[0006] Furthermore, an overflow channel is provided between the separation chamber and the overflow chamber, and an overflow baffle is provided above the overflow channel to prevent overflow liquid from flowing directly into the overflow chamber.

[0007] Furthermore, a first online analyzer is also connected to the static separation tank. The first online analyzer is located on the outer wall of the static separation tank at the location of the separation chamber, and the end of the first online analyzer passes through the static separation tank and extends into the separation chamber.

[0008] Furthermore, the water cooling mechanism includes a first water cooler and a second water cooler. The inlet end of the first water cooler is used to connect to an external pre-distillation column, the outlet end of the first water cooler is connected to the inlet end of the second water cooler, and the outlet end of the second water cooler is connected to the inlet end of the static separation tank. The first and second water coolers are used to perform staged condensation of the gas input from the pre-distillation column.

[0009] Furthermore, the second water cooler is provided with a liquid phase outlet and a gas phase outlet. The liquid phase outlet is connected to a static separation tank, and the gas phase outlet is connected to a second online analyzer. The gas phase outlet is used to vent the condensed gas after it has been detected by the second online analyzer.

[0010] Furthermore, a reflux trough is connected between the reflux outlet end of the static separation tank and the water cooling mechanism. The reflux trough is used to buffer and collect the reflux liquid introduced through the valve.

[0011] The beneficial effects of this utility model are: This invention's extraction device effectively separates light components, resulting in methanol distillation products from both pressurized and atmospheric distillation towers exceeding standard quality. The material enters a static separation tank via the liquid phase outlet of the water-cooled mechanism. In the separation chamber of the static separation tank, it undergoes static separation. Upper impurities overflow into the overflow chamber and then into the recovery chamber, finally entering the fusel oil recovery system. Methanol, on the other hand, flows back into the water-cooled mechanism through the outlet at the bottom of the separation chamber for cyclic condensation and separation. This device effectively separates and extracts light components from methanol while ensuring methanol recovery rate and purity. It allows for more thorough separation of light components, and the methanol portion can be fully condensed and recovered. The static separation tank of this invention requires no energy consumption and can be welded from stainless steel, thus reducing equipment operating costs. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the process structure of the separation and extraction device of this utility model.

[0013] Figure label: 1-Pre-distillation column, 2-Air cooler, 3-First water cooler, 4-Second water cooler, 5-Static separation tank, 6-Valve, 7-Reflux tank, 8-Second online analyzer 501 - First online analyzer, 502 - Separation chamber, 503 - Overflow channel, 504 - Overflow liquid baffle, 505 - Overflow chamber, 506 - Recovery chamber. Detailed Implementation

[0014] The present invention will now be described in detail with reference to the accompanying drawings and embodiments. Example 1

[0015] A device for separating and extracting light components in methanol distillation pretreatment includes a water-cooling mechanism and a static separation tank 5. The outlet end of the water-cooling mechanism is connected to the inlet end of the static separation tank 5. The static separation tank 5 is provided with a reflux outlet end and a recovery outlet end. The reflux outlet end is connected to the inlet end of the water-cooling mechanism via a valve 6. The static separation tank 5 contains a separation chamber 502, an overflow chamber 505, and a recovery chamber 506 that are interconnected. The separation chamber 502 is connected to the reflux outlet end, and the recovery chamber 506 is connected to the recovery outlet end. The overflow chamber 505 is located between the separation chamber 502 and the recovery chamber 506. The separation chamber 502 is used to separate impurities and methanol and to transport methanol back to the water-cooling mechanism from the reflux outlet end via the valve 6. The overflow chamber 505 is used to collect impurities overflowing from the separation chamber 502. The recovery chamber 506 is used to discharge the impurities transported from the overflow chamber 505 to an external recovery system via the recovery outlet end.

[0016] In this embodiment, to improve the purity of methanol, a method of static separation and overflow is used to remove impurities. This method is based on the principle of physical separation, utilizing the density differences and miscibility / incompatibility of different components, as well as the principle of gravity sedimentation. During the static separation process, due to the different densities of impurities, the lighter components will float to the top of the separation chamber 502, while methanol will settle to the bottom. Overflow is a separation method that controls the liquid level to allow the upper liquid or target component to overflow from the top of the container, while retaining the lower layer in the container. Used in conjunction with static separation, this principle can effectively separate the different parts after static stratification. In this embodiment, the specific overflow structure of the separation chamber 502 and the overflow chamber 505 can refer to the structure in the existing related technology and be selected for application in this utility model, and will not be described in detail here.

[0017] The working process of this utility model is as follows: the material enters the static separation tank 5 through the liquid phase outlet of the water-cooling mechanism, and undergoes static separation in the separation chamber 502 of the static separation tank 5. The upper impurities overflow into the overflow chamber 505 and then into the recovery chamber 506, finally entering the fusel oil recovery system. Methanol, on the other hand, flows back into the water-cooling mechanism through the outlet below the separation chamber 502 for circulating condensation and separation. This process, through static separation and the slow overflow, effectively separates the upper impurities, which then overflow into the overflow chamber 505. Using the overflow chamber 505 as an intermediate buffer space, the separated impurities are output to the recovery chamber 506 for recovery. This separation process avoids methanol being discharged along with the impurities, thus preventing the methanol recovery rate from being affected. Example 2

[0018] This embodiment is based on the aforementioned embodiment. In this embodiment, an overflow channel 503 is provided between the separation chamber 502 and the overflow chamber 505, and an overflow baffle 504 is provided above the overflow channel 503. The overflow baffle 504 is used to prevent overflow liquid from flowing directly into the overflow chamber 505. Figure 1 As shown, the overflow baffle 504 can be set on the upper left side of the overflow chamber 505. After the material is separated by settling in the separation chamber 502, the impurities above enter the overflow chamber 505 through the overflow channel 503. When the liquid level in the separation chamber 502 is high and the overflow flow is high in a short time, the overflow baffle 504 can block the liquid overflowing from the high liquid level, so as to avoid the liquid stratification state being affected by fluctuations due to excessively fast overflow, thereby ensuring the stability of the overflow. Example 3

[0019] This embodiment is based on the aforementioned embodiment. In this embodiment, a first online analyzer 501 is also connected to the static separation tank 5. The first online analyzer 501 is disposed on the outer wall of the static separation tank 5 at the location of the separation chamber 502. The end of the first online analyzer 501 passes through the static separation tank 5 and extends into the separation chamber 502.

[0020] In this embodiment, a first online analyzer 501 is used for detection. When the methanol content is ≤60%, the valve 6 leading to the reflux tank 7 is closed, which ensures the content of light components in the pre-distillation column 1 and guarantees that the product quality meets the standards. Preferably, the pre-distillation column 1 can be heated by low-pressure steam from the external pipeline to the methanol solution at the bottom of the pre-distillation column 1. The operating temperature of the column top / bottom is controlled by a regulating valve at approximately 82℃ / 85℃, and the operating pressure of the column top / bottom is approximately 0.05 MPa(G) / 0.08 MPa(G). Example 4

[0021] This embodiment is based on the aforementioned embodiment. In this embodiment, the water cooling mechanism includes a first water cooler 3 and a second water cooler 4. The inlet end of the first water cooler 3 is connected to the pre-distillation column 1, and the outlet end of the first water cooler 3 is connected to the inlet end of the second water cooler 4. The outlet end of the second water cooler 4 is connected to the inlet end of the static separation tank 5. The first water cooler 3 and the second water cooler 4 are used to perform staged condensation of the gas input from the pre-distillation column 1. In this embodiment, the water cooling mechanism uses the first water cooler 3 and the second water cooler 4 connected in series to perform staged condensation of the gas from the pre-distillation column 1: First, the high-temperature gas enters the first water cooler 3 and partially condenses at a lower temperature, then enters the second water cooler 4 and further condenses at an even lower temperature, achieving stepped cooling and gradual separation; finally, the condensate enters the static separation tank 5 for further separation. The principle of this staged condensation technology utilizes the condensation characteristics of different components at different temperatures. By gradually reducing the temperature, the condensation efficiency and selectivity are improved. This not only avoids the excessive energy consumption caused by single low-temperature condensation, but also effectively improves the separation effect of light and heavy components. It has the effects of energy saving, sufficient condensation, high separation efficiency and stable system operation.

[0022] In a preferred embodiment, the second water cooler 4 is equipped with a liquid phase outlet and a gas phase outlet. The liquid phase outlet is connected to the static separation tank 5, and the gas phase outlet is connected to a second online analyzer 8. The gas phase outlet is used to vent the condensed gas after it has been detected by the second online analyzer 8. The second online analyzer 8 can automatically adjust the outlet temperature of the second water cooler 4 based on the monitored data, thereby improving the methanol recovery rate. The mixed fluid is cooled by the second water cooler 4, causing it to partially or completely condense into a liquid phase. The uncondensed gas is discharged from the gas phase outlet. The liquid phase enters the static separation tank 5 for further separation through the liquid phase outlet, while the gas phase is monitored for its composition in real time by the second online analyzer 8, and the outlet temperature of the second water cooler 4 is automatically adjusted based on the monitoring data to optimize the condensation effect. This structure, through temperature control and real-time monitoring, effectively improves the methanol condensation recovery rate, reduces methanol loss due to venting with the gas, and enhances the overall energy efficiency and economy of the process.

[0023] As a preferred embodiment, by installing an online methanol analyzer on the vent line of the pre-distillation column 1, the outlet temperature of the water cooler can be automatically adjusted, thereby increasing the methanol recovery rate.

[0024] Preferably, the online analyzer of this utility model can adopt the following models: Models such as MAZ-Ra300-CH3OH, MAYD-2001JC, and MAYD-2001 can be used for methanol content analysis in solid and liquid phase samples. They are suitable for scenarios such as reaction endpoint determination and product qualification rate control. Some models can also detect other parameters.

[0025] JY-M300-CH4O: Can detect methanol gas concentration, suitable for hazardous locations, can output multiple standard signals, and supports remote monitoring. Example 5

[0026] This embodiment is based on the aforementioned embodiment. In this embodiment, a reflux tank 7 is also connected between the reflux outlet end of the static separation tank 5 and the water cooling mechanism. The reflux tank 7 is used to buffer and collect the reflux liquid introduced through the valve 6. This working process utilizes the reflux tank 7 as an intermediate transition container to buffer and temporarily store the liquid returning from the separation tank, thereby avoiding direct high-speed impact of the liquid on the water cooling mechanism, which could cause equipment damage or system fluctuations. The liquid flows out of the static separation tank 5, and after the flow rate is controlled by the valve 6, it enters the reflux tank 7 for buffering and collection, and then is smoothly introduced into the water cooling mechanism for condensation. This structure effectively alleviates the impact force of the liquid flow, improves the stability and safety of the system operation, and also helps to improve the uniformity and efficiency of subsequent cooling processes, ensuring the smooth and controllable operation of the entire separation and cooling process.

[0027] The embodiments described above merely illustrate specific implementations of this utility model, and while the descriptions are detailed, they should not be construed as limiting the scope of this utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these modifications and improvements all fall within the protection scope of this utility model.

Claims

1. A device for separating and extracting light components in methanol distillation pretreatment, characterized in that, It includes a water-cooling mechanism and a static separation tank. The outlet end of the water-cooling mechanism is connected to the inlet end of the static separation tank. The static separation tank is provided with a reflux outlet end and a recovery outlet end. The reflux outlet end is connected to the inlet end of the water-cooling mechanism through a valve. The static separation tank is provided with a separation chamber, an overflow chamber and a recovery chamber that are interconnected. The separation chamber is connected to the reflux outlet, the recovery chamber is connected to the recovery outlet, and the overflow chamber is located between the separation chamber and the recovery chamber. The separation chamber is used to separate impurities and methanol and to transport methanol back to the water cooling mechanism through a valve from the reflux outlet. The overflow chamber is used to collect impurities overflowing from the separation chamber. The recovery chamber is used to discharge the impurities transported from the overflow chamber to the external recovery system from the recovery outlet.

2. The apparatus for separating and extracting light components in methanol distillation pretreatment according to claim 1, characterized in that, An overflow channel is provided between the separation chamber and the overflow chamber, and an overflow baffle is provided above the overflow channel to prevent overflow liquid from flowing directly into the overflow chamber.

3. The apparatus for separating and extracting light components in methanol distillation pretreatment according to claim 1, characterized in that, The static separation tank is also connected to a first online analyzer. The first online analyzer is located on the outer wall of the static separation tank at the location of the separation chamber. The end of the first online analyzer passes through the static separation tank and extends into the separation chamber.

4. The apparatus for separating and extracting light components in methanol distillation pretreatment according to claim 1, characterized in that, The water cooling mechanism includes a first water cooler and a second water cooler. The inlet end of the first water cooler is used to connect to an external pre-distillation column. The outlet end of the first water cooler is connected to the inlet end of the second water cooler. The outlet end of the second water cooler is connected to the inlet end of the static separation tank. The first and second water coolers are used to perform staged condensation of the gas input from the pre-distillation column.

5. The apparatus for separating and extracting light components in methanol distillation pretreatment according to claim 4, characterized in that, The second water cooler is provided with a liquid phase outlet and a gas phase outlet. The liquid phase outlet is connected to a static separation tank, and the gas phase outlet is connected to a second online analyzer. The gas phase outlet is used to vent the condensed gas after it has been detected by the second online analyzer.

6. The apparatus for separating and extracting light components in methanol distillation pretreatment according to claim 1, characterized in that, A reflux trough is also connected between the reflux outlet end of the static separation tank and the water cooling mechanism. The reflux trough is used to buffer and collect the reflux liquid introduced through the valve.

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