Crude methanol recycling system

Abstract

The utility model relates to the technical field of crude methanol liquid collection, in particular to a crude methanol recycling system, which comprises a methanol rectification unit, an underground tank, a crude methanol delivery pump and a crude methanol collection tank which are sequentially connected. The crude methanol collection tank is connected with the methanol rectification unit; crude methanol generated by the methanol rectification unit is collected by arranging the normal-pressure underground tank, then the collected crude methanol is input into the crude methanol collection tank by utilizing the crude methanol delivery pump, and a crude methanol raw material is provided for the methanol rectification unit through the crude methanol collection tank, so that the recycling of the crude methanol is realized; the problem that crude methanol with different pressures output by the methanol rectification unit cannot be directly discharged to the crude methanol collection tank is avoided; the whole structure is simple, the cost is low, the situation that the collected crude methanol is independently recycled through new system equipment can be avoided, the cost is reduced, and the actual recycling requirement is met.

Description

Technical Field

[0001] The utility model relates to the technical field of crude methanol liquid collection, and specifically relates to a crude methanol recovery and utilization system. Background Art

[0002] In the process of methanol production, the methanol rectification device is prepared by a pre-rectification tower, a pressurized rectification tower, an atmospheric rectification tower and a stripping tower. However, in the process of methanol preparation, crude methanol of different qualities will be produced. At this time, the produced crude methanol will be collected and used for recycling and then rectified again to prepare methanol.

[0003] For example, the Chinese utility model patent with the application number of 201920946736.6 provides a methanol recovery device, which includes a crude methanol collection unit for collecting the crude methanol discharged from the expansion tank and the methanol recovery tower.

[0004] Among them, in the actual working process, the crude methanol collection unit will refine the collected crude methanol. However, although refining the crude methanol again can reduce waste, it will increase the recovery cost, so it cannot meet the actual recovery needs. Summary of the Utility Model

[0005] The purpose of the utility model is to provide a crude methanol recovery and utilization system to solve the technical problem that the current cost of crude methanol recovery and treatment is high and does not meet the actual recovery needs.

[0006] To achieve the above purpose, the utility model provides the following technical solutions:

[0007] A crude methanol recovery and utilization system includes a methanol rectification unit, an underground tank, a crude methanol transfer pump and a crude methanol collection tank. The methanol rectification unit, the underground tank, the crude methanol transfer pump and the crude methanol collection tank are connected in sequence, and the crude methanol collection tank is connected to the methanol rectification unit.

[0008] Further defined, a liquid level transmitter is arranged in the underground tank, and the liquid level transmitter is signal-connected to the crude methanol transfer pump. The liquid level transmitter is close to the top and / or bottom of the underground tank.

[0009] Further defined, a remote pressure transmitter is arranged on the underground tank. The crude methanol recovery and utilization system further includes an audible and visual warning device, and the remote pressure transmitter is signal-connected to the audible and visual warning device.

[0010] Further defined, the crude methanol recovery and utilization system further includes a water seal tank. The water seal tank is communicated with the underground tank. An exhaust pipe is arranged on the water seal tank, and a breather valve is arranged on the exhaust pipe.

[0011] Further defined, the methanol rectification unit is connected to the underground tank through a crude methanol inlet pipe, and a pneumatic valve for crude methanol inlet is arranged on the crude methanol inlet pipe.

[0012] Further defined, the pneumatic valve for crude methanol inlet is signal-connected to a remote pressure transmitter.

[0013] Further defined, an inlet pipe for waste methanol is also arranged on the underground tank, and the inlet pipe for waste methanol is located on one side of the crude methanol inlet pipe.

[0014] Further defined, the methanol rectification unit includes a pre-column, a pressurized column, an atmospheric column, and a stripping column arranged in sequence, and the pre-column, the pressurized column, the atmospheric column, and the stripping column are all connected to the crude methanol inlet pipe.

[0015] Compared with the prior art, the beneficial effects of the present utility model are as follows:

[0016] 1. The present utility model collects the crude methanol generated by the methanol rectification unit through an underground tank at atmospheric pressure, and then uses a crude methanol transfer pump to input the collected crude methanol into a crude methanol collection tank, and provides crude methanol raw materials for the methanol rectification unit through the crude methanol collection tank, so as to realize the recycling of crude methanol, and avoid the problem that the crude methanol with different pressures output by the methanol rectification unit cannot be directly discharged into the crude methanol collection tank; the overall structure is simple and the cost is low, and it can also avoid using a new system device to separately recycle the collected crude methanol, reduce the cost, and meet the actual recycling requirements.

[0017] 2. The present utility model avoids the liquid level of the underground tank being too high and / or too low by setting a liquid level transmitter, ensuring the stable use of the underground tank; at the same time, a water seal tank and a remote pressure transmitter are arranged on the underground tank. On the one hand, the pressure in the underground tank can be released in time, and on the other hand, it can also give a reminder when the pressure in the underground tank is abnormal, improving the safety and reliability of the use of the underground tank.

[0018] 3. The present utility model can also collect the waste methanol and crude methanol generated in the production process through the inlet pipe for waste methanol by setting an underground tank at atmospheric pressure, so as to realize recycling and reuse, further reducing the recycling cost and difficulty, and meeting the actual production requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the crude methanol recycling system of the present utility model;

[0020] In the figure: 1 - methanol rectification unit; 2 - underground tank; 3 - crude methanol transfer pump; 4 - crude methanol collection tank; 5 - water seal tank; 6 - crude methanol outlet pipe; 7 - crude methanol inlet pipe; 8 - inlet pipe for waste methanol; a - liquid level transmitter; b - remote pressure transmitter; c - breather valve; d - pneumatic valve for crude methanol inlet. Detailed implementation manners

[0021] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present utility model clearer and more understandable, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. The specific embodiments described herein are only used to explain the present utility model and are not used to limit the present utility model. Specific details such as specific system structures and technologies are proposed to more thoroughly understand the embodiments of the present utility model. The described embodiments are part of the embodiments of the present disclosure, rather than all of the embodiments. However, those skilled in the art should understand that the present utility model can also be implemented in other embodiments without these specific details. Based on the embodiments in the present disclosure, all other embodiments obtained by those skilled in the art without creative efforts belong to the scope of protection of the present utility model disclosure.

[0022] Embodiment 1

[0023] Referring to Figure 1 , this embodiment provides a crude methanol recovery and utilization system, which includes a methanol rectification unit 1, an underground tank 2, a crude methanol transfer pump 3 and a crude methanol collection tank 4 connected in sequence, and the crude methanol collection tank 4 is connected to the methanol rectification unit 1.

[0024] Among them, the methanol rectification unit 1 is used to prepare high-quality methanol, and it can be selectively prepared by passing crude methanol through a pre-column, a pressurized column, an atmospheric column and a stripping column in sequence. During the production process, waste crude methanol will be generated in the pre-column, pressurized column, atmospheric column and stripping column. At this time, the waste crude methanol generated by the methanol rectification unit 1 can be selectively transported to the underground tank 2 through the crude methanol inlet pipe 7.

[0025] At the same time, during the shutdown and maintenance period of the methanol rectification unit 1, it is necessary to empty the methanol and crude methanol remaining in the equipment. At this time, the residual methanol in the equipment can also be transported to the underground tank 2 to improve the recovery range of crude methanol and reduce the recovery cost.

[0026] The crude methanol collection tank 4 is used to store crude methanol raw materials. The inside of the crude methanol collection tank 4 is under high pressure. The crude methanol collection tank 4 transports the crude methanol to the methanol rectification unit 1 through the crude methanol outlet pipe 6 to realize the production of refined methanol.

[0027] Since the working states of the pre-column, pressurized column, atmospheric column and stripping column are different, and the discharge pressures of the crude methanol are different, they cannot be directly discharged into the crude methanol collection tank 4. Therefore, the crude methanol transfer pump 3 is used to pressurize and transport the crude methanol collected in the underground tank 2 to the crude methanol collection tank 4, so as to realize the recovery of crude methanol. The overall structure is simple and the cost is low, the operation is simple, the maintenance cost is low, and the recovery cost of crude methanol is reduced. Therefore, it can meet the actual recovery requirements of crude methanol.

[0028] Furthermore, to avoid excessive methanol input into the underground tank 2, a liquid level transmitter a can be installed inside the underground tank 2. The liquid level transmitter a is installed at a position near the top inside the underground tank 2 and is signal-connected to the crude methanol transfer pump 3, so that the crude methanol transfer pump 3 increases the pumping power when the crude methanol liquid level in the underground tank 2 is too high.

[0029] At the same time, to avoid the idling of the crude methanol transfer pump 3 when the crude methanol liquid level in the underground tank 2 is too low, the liquid level transmitter a can also be installed at a position near the bottom inside the underground tank 2. At this time, when the crude methanol liquid level is too low, the crude methanol transfer pump 3 stops running.

[0030] Preferably, a liquid level transmitter a is also installed at the middle position of the height inside the underground tank 2. At this time, the pumping power of the crude methanol transfer pump 3 can be reduced when the liquid level is lower than the middle height, and the pumping power of the crude methanol transfer pump 3 can be increased when the liquid level is higher than the middle height, meeting the actual collection requirements of crude methanol.

[0031] Since crude methanol under different pressures is transported to the underground tank 2 through the crude methanol inlet pipe 7, the internal pressure of the underground tank 2 is likely to be unstable. To avoid the risk of accidents caused by excessive pressure in the underground tank 2, a water seal tank 5 is installed outside the underground tank 2.

[0032] The water seal tank 5 is connected to the underground tank 2. An exhaust pipe is provided on the water seal tank 5, and a breathing valve c is provided on the exhaust pipe. The high-pressure gas in the underground tank 2 is filtered to remove easily soluble harmful gases such as methanol gas after passing through water in the water seal tank 5 and then discharged, thus ensuring the safe and reliable use of the underground tank 2.

[0033] Furthermore, to avoid the failure of the breathing valve c or the blockage of the water seal tank 5, resulting in the inability to discharge the internal pressure of the underground tank 2 in time, leading to excessive internal pressure in the underground tank 2 and being unable to be detected in time, a remote pressure transmitter b is installed on the underground tank 2 at this time.

[0034] The remote pressure transmitter b is used to monitor the internal pressure of the underground tank 2. The remote pressure transmitter b can be directly signal-connected to an audible and visual warning device to give an audible and visual warning when the set pressure value is exceeded, providing timely reminder to ensure the stable use of crude methanol.

[0035] Preferably, to further improve the reliable use of crude methanol, a pneumatic control valve d for crude methanol inlet is installed on the crude methanol inlet pipe 7 to control the opening and closing of the discharge of crude methanol from the methanol rectification unit 1 to the underground tank 2. At this time, the pneumatic control valve d for crude methanol inlet is signal-connected to the remote pressure transmitter b to close the pneumatic control valve d for crude methanol inlet when the internal pressure of the underground tank 2 is too high, avoiding further increasing the internal pressure of the underground tank 2.

[0036] Further explanation: During the actual production process, operations such as sampling and testing the methanol obtained from different production links are required. After the testing and analysis are completed, this part of methanol can be collected to avoid waste of resources and reduce production costs. At the same time, since the underground tank 2 is an atmospheric tank, an abandoned methanol inlet pipe 8 can be optionally provided on the underground tank 2 to collect the refined methanol and crude methanol discarded during sampling in production and then transport them to the underground tank 2 through the abandoned methanol inlet pipe 8, further improving the recovery efficiency and scope of methanol, while reducing the recovery difficulty and cost to meet the actual recovery requirements.

[0037] Obviously, the above-described embodiments are only a part of the embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0038] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0039] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A crude methanol recycling system, characterized in that, It includes a methanol rectification unit (1), an underground tank (2), a crude methanol transfer pump (3) and a crude methanol collection tank (4). The methanol rectification unit (1), the underground tank (2), the crude methanol transfer pump (3) and the crude methanol collection tank (4) are connected in sequence. The crude methanol collection tank (4) is connected to the methanol rectification unit (1). Among them, the underground tank (2) is an atmospheric pressure underground tank, and the atmospheric pressure underground tank collects the crude methanol produced by the methanol rectification unit (1). The crude methanol transfer pump (3) inputs the collected crude methanol into the crude methanol collection tank (4).

2. The crude methanol recovery and utilization system according to claim 1, wherein A liquid level transmitter (a) is arranged in the underground tank (2). The liquid level transmitter (a) is signal-connected to the crude methanol transfer pump (3), and the liquid level transmitter (a) is close to the top and / or bottom of the underground tank (2).

3. The crude methanol recycling system according to claim 2, characterized in that, A remote pressure transmitter (b) is arranged on the underground tank (2). The crude methanol recycling system further includes an audible and visual warning device, and the remote pressure transmitter (b) is signal-connected to the audible and visual warning device.

4. The crude methanol recycling system according to claim 3, wherein The crude methanol recycling system further includes a water seal tank (5). The water seal tank (5) is communicated with the underground tank (2). An exhaust pipe is arranged on the water seal tank (5), and a breathing valve (c) is arranged on the exhaust pipe.

5. The crude methanol recycling system according to claim 4, characterized in that, The methanol rectification unit (1) is communicated with the underground tank (2) through a crude methanol inlet pipe (7). A crude methanol inlet pneumatic valve (d) is arranged on the crude methanol inlet pipe (7).

6. The crude methanol recycling system according to claim 5, wherein The crude methanol inlet pneumatic valve (d) is signal-connected to the remote pressure transmitter (b).

7. The crude methanol recycling system according to claim 6, characterized in that, An abandoned methanol inlet pipe (8) is further arranged on the underground tank (2), and the abandoned methanol inlet pipe (8) is located on one side of the crude methanol inlet pipe (7).

8. The crude methanol recycling system according to claim 7, wherein The methanol rectification unit (1) includes a pre-column, a pressurizing column, an atmospheric column and a stripping column arranged in sequence. The pre-column, the pressurizing column, the atmospheric column and the stripping column are all communicated with the crude methanol inlet pipe (7).

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