Device for continuously recovering methanol from ethyl maltol mother liquor

Abstract

The utility model discloses a device for continuously recovering methanol from ethyl maltol mother liquor. The device comprises a central circulating tubular evaporator, a glass heat exchanger, a flow control device and a mother liquor supply device, according to the utility model, the continuous heating treatment of mother liquor is realized by adopting the central circulating tubular evaporator, so that the continuity of methanol recovery is guaranteed, and the production efficiency is improved; the glass heat exchanger is used for condensing methanol steam by taking mother liquor as a refrigerant, low-temperature energy of the mother liquor is fully utilized, the steam consumption of the central circulating tubular evaporator is reduced, and the temperature sensor and the electric control regulating valve are combined with the central circulating tubular evaporator to regulate the steam inlet amount according to the temperature of feed liquid. Automatic control over the whole continuous production process is achieved, parameters of all links can be accurately controlled, an inlet and an outlet of the glass heat exchanger are connected through acid-corrosion-resistant hoses, reliability and stability of device connection are enhanced, and the service life of the device in the working environment containing acidic substances is prolonged.

Description

Technical Field

[0001] This utility model relates to the field of chemical production technology, and in particular to a device for continuous recovery of methanol from ethyl maltol mother liquor. Background Technology

[0002] In the production of ethyl maltol, the mother liquor after centrifugation of the yellow product's chilled liquid contains a large amount of methanol and ethyl maltol dissolved in an aqueous methanol solution. Recovering and utilizing the methanol in the mother liquor is of great significance, as it reduces raw material consumption, simplifies wastewater treatment, and facilitates the extraction and recovery of dissolved ethyl maltol, thereby increasing product yield. However, traditional treatment methods often have several shortcomings. On the one hand, single-batch methanol recovery is inefficient, consuming significant time and labor costs, making it difficult to meet the demands of large-scale industrial production for timely mother liquor treatment and resource recovery. On the other hand, some processes have limited methanol recovery rates, resulting in a large amount of methanol remaining in the mother liquor and being wasted. This not only increases production costs but also, if improperly handled, can cause environmental pollution. Existing recovery processes and equipment often suffer from problems such as the inability to achieve continuous production, low energy efficiency, and difficulty in accurately controlling relevant parameters. Therefore, it is necessary to improve the corresponding recovery equipment to meet the demands of efficient, continuous, and automated production. Utility Model Content

[0003] The purpose of this invention is to address the shortcomings of existing technologies by proposing a device for the continuous recovery of methanol from ethyl maltol mother liquor.

[0004] To achieve the above objectives, this utility model adopts the following technical solution: a device for continuous methanol recovery from ethyl maltol mother liquor, comprising a central circulating tubular evaporator, a glass heat exchanger, a flow control device, and a mother liquor supply device. The central circulating tubular evaporator has an inlet and a steam condensate outlet fixedly connected sequentially from top to bottom on its left wall. An evaporator steam inlet is fixedly connected to the right wall of the central circulating tubular evaporator. Steam pipes and liquid outlets are fixedly connected to the upper and lower ends of the central circulating tubular evaporator, respectively. A refrigerant inlet and a refrigerant outlet are fixedly connected to the left and right sides of the glass heat exchanger, respectively. A heat exchanger steam inlet and a condensate outlet are fixedly connected to the upper and lower ends of the glass heat exchanger, respectively. The refrigerant inlet and outlet are connected to each other via a heat exchange coil at their respective ends inside the glass heat exchanger. The ends of the refrigerant inlet and outlet furthest from the glass heat exchanger are fixedly connected to a first connecting pipe and a second connecting pipe via a set of flexible connecting structures.

[0005] As a further description of the above technical solution:

[0006] The first connecting pipe is connected to a mother liquor pipe at the end furthest from the refrigerant inlet. A flow control device for controlling the flow rate of the mother liquor is provided between the first connecting pipe and the mother liquor pipe. The second connecting pipe is connected to the end furthest from the refrigerant outlet and the end furthest from the central circulating tubular evaporator at the liquid inlet. A temperature detection structure for detecting the temperature of the mother liquor is provided between the second connecting pipe and the liquid inlet.

[0007] As a further description of the above technical solution:

[0008] The flexible connection structure includes two sets of first flanges and second flanges. The two sets of first flanges are respectively fixedly connected to the end of the first connecting pipe away from the mother liquid pipeline and the end of the second connecting pipe away from the liquid inlet. A flexible hose is fixedly connected between the opposite sides of the first flange and the second flange. The flexible hose is fixedly connected to the first flange through a third flange and to the second flange through a fourth flange. The flexible hose consists of an inner tube and an outer tube wrapped around the outer wall of the inner tube.

[0009] As a further description of the above technical solution:

[0010] The inner tube is a high-density polyethylene corrugated pipe, and the outer tube is a stainless steel corrugated pipe.

[0011] As a further description of the above technical solution:

[0012] The flow control device is an electrically controlled regulating valve, which is fixedly connected between the first connecting pipe and the mother liquor pipe.

[0013] As a further description of the above technical solution:

[0014] The temperature detection structure is a temperature sensor, which is fixedly connected between the second connecting pipe and the liquid inlet.

[0015] As a further description of the above technical solution:

[0016] The end of the mother liquor pipeline furthest from the flow control device is connected to the mother liquor supply device.

[0017] This utility model has the following beneficial effects:

[0018] 1. Compared with existing technologies, this device for continuous methanol recovery from ethyl maltol mother liquor uses a central circulating tubular evaporator to achieve continuous heating of the mother liquor, ensuring the continuity of methanol recovery and improving production efficiency. It utilizes a glass heat exchanger to condense methanol vapor using the mother liquor as a refrigerant, fully utilizing the low-temperature energy of the mother liquor, reducing the steam consumption of the central circulating tubular evaporator, lowering energy consumption, and improving overall energy utilization efficiency. By installing a temperature sensor at the refrigerant outlet of the glass heat exchanger and configuring an electrically controlled regulating valve at the refrigerant inlet to control the mother liquor flow rate, combined with the function of the central circulating tubular evaporator to adjust the steam feed rate according to the feed liquid temperature, the entire continuous production process is automated. This allows for precise control of parameters at each stage, ensuring the effectiveness of methanol recovery and the smooth operation of subsequent ethyl maltol extraction and recovery.

[0019] 2. Compared with the existing technology, the device for continuous recovery of methanol from ethyl maltol mother liquor uses acid-resistant hoses for connecting the inlet and outlet of the glass heat exchanger, which enhances the reliability and stability of the device connection and extends the service life of the device in working environments containing acidic substances. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the overall structure of a device for continuous methanol recovery from ethyl maltol mother liquor proposed in this utility model.

[0021] Figure 2 This invention proposes a device for the continuous recovery of methanol from ethyl maltol mother liquor. Figure 1 A magnified view of a section at point A in the middle;

[0022] Figure 3 This is a partial cross-sectional view of the internal structure of the hose in the apparatus for continuous methanol recovery from ethyl maltol mother liquor according to the present invention.

[0023] Legend:

[0024] 1. Central circulating tubular evaporator; 101. Liquid inlet; 102. Evaporator steam inlet; 103. Liquid outlet; 104. Steam condensate outlet; 2. Glass heat exchanger; 201. Refrigerant inlet; 202. Refrigerant outlet; 203. Heat exchanger steam inlet; 204. Condensate outlet; 205. Heat exchange coil; 3. Steam pipe; 4. Mother liquor pipe; 5. Electrically controlled regulating valve; 6. Temperature sensor; 7. First connecting pipe; 8. Second connecting pipe; 9. First flange; 10. Second flange; 11. Third flange; 12. Fourth flange; 13. Outer pipe; 14. Inner pipe. Detailed Implementation

[0025] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0026] Reference Figures 1 to 3 This utility model provides a device for continuous methanol recovery from ethyl maltol mother liquor: It includes a central circulating tubular evaporator 1, a glass heat exchanger 2, a flow control device, and a mother liquor supply device. The left wall of the central circulating tubular evaporator 1 is fixedly connected from top to bottom to an inlet 101 and a steam condensate outlet 104. The right wall of the central circulating tubular evaporator 1 is fixedly connected to an evaporator steam inlet 102. Steam pipes 3 and outlet 103 are fixedly connected to the upper and lower ends of the central circulating tubular evaporator 1, respectively. The glass heat exchanger 2 is fixedly connected to the left and right sides... A refrigerant inlet 201 and a refrigerant outlet 202 are connected to the glass heat exchanger 2. A heat exchanger steam inlet 203 and a condensate outlet 204 are fixedly connected to the upper and lower ends of the glass heat exchanger 2, respectively. The refrigerant inlet 201 and the refrigerant outlet 202 are connected to each other via a heat exchange coil 205. In this embodiment, the liquid outlet 103 is connected to the extraction device for the subsequent ethyl maltol mother liquor concentrate. The central circulating tubular evaporator 1 has a commercially available control system that adjusts the steam flow rate based on the feed liquid temperature. During use, the mother liquor flows into the refrigerant inlet 201 of the glass heat exchanger 2 through the mother liquor pipe 4, and the electrically controlled regulating valve 5 precisely controls the mother liquor flow rate. After entering the glass heat exchanger 2, the mother liquor acts as a refrigerant and exchanges heat with methanol vapor from the top steam pipe 3 of the central circulating tubular evaporator 1 (which enters through the heat exchanger steam inlet 203 at the top of the glass heat exchanger 2). The methanol vapor is condensed into a methanol solution upon cooling and flows into a methanol receiving tank for collection via the glass heat exchanger condensate outlet 204. Meanwhile, the mother liquor, which serves as the refrigerant, absorbs heat and its temperature rises. The temperature is monitored in real time by the temperature sensor 6 installed at the refrigerant outlet 202 of the glass heat exchanger 2, and the outlet mother liquor temperature is controlled between 25-35℃. The mother liquor after heat exchange flows out from the refrigerant outlet 202 of the glass heat exchanger 2 and enters the central circulating tubular evaporator 1 through the liquid inlet 101.

[0027] In the central circulating tubular evaporator 1, steam is introduced through the steam inlet 102 to further heat the mother liquor, ensuring the complete evaporation of residual methanol and guaranteeing methanol recovery. The central circulating tubular evaporator 1 automatically adjusts the steam feed rate based on the feed liquor temperature to maintain a suitable temperature for a continuous and stable evaporation process. The mother liquor after methanol evaporation flows out from the outlet 103 of the central circulating tubular evaporator 1 and is transported to the extraction unit for subsequent extraction and recovery of ethyl maltol.

[0028] To achieve a flexible connection between the two ends of the glass heat exchanger 2, the ends of the refrigerant inlet 201 and the refrigerant outlet 202 away from the glass heat exchanger 2 are respectively fixedly connected to a first connecting pipe 7 and a second connecting pipe 8 through a set of flexible connection structures. The flexible connection structure includes two sets of first flanges 9 and second flanges 10. The two sets of first flanges 9 are respectively fixedly connected to the end of the first connecting pipe 7 away from the mother liquid pipe 4 and the end of the second connecting pipe 8 away from the liquid inlet 101. A flexible hose is fixedly connected between the opposite sides of the first flanges 9 and the second flanges 10. The flexible hose is fixedly connected to the first flange 9 through a third flange 11 and to the second flange 10 through a fourth flange 12. The flexible hose consists of an inner tube 14 and an outer tube 13 wrapped around the outer wall of the inner tube 14. By setting the flexible hose, the vibration and displacement that may occur during the operation of the device can be effectively buffered, and the packaging device can operate normally.

[0029] To improve the acid corrosion resistance of the connection, the inner tube 14 is a high-density polyethylene corrugated pipe and the outer tube 13 is a stainless steel corrugated pipe. The high-density polyethylene corrugated pipe can effectively buffer the vibration and displacement that may occur during the operation of the device through its corrugated pipe expansion and contraction characteristics. On the other hand, it ensures the sealing of the connection. Even under the long-term influence of acidic mother liquor and other substances, it can maintain a good connection state and ensure the normal operation of the device.

[0030] In order to accurately control the flow rate of the mother liquor, the end of the first connecting pipe 7 away from the refrigerant inlet 201 is connected to the mother liquor pipeline 4, and the end of the mother liquor pipeline 4 away from the flow control device is connected to the mother liquor supply device. A flow control device for controlling the flow rate of the mother liquor is set between the first connecting pipe 7 and the mother liquor pipeline 4. The flow control device is an electrically controlled regulating valve 5. The electrically controlled regulating valve 5 is fixedly connected between the first connecting pipe 7 and the mother liquor pipeline 4. The electrically controlled regulating valve 5 is used to accurately regulate the flow rate of the mother liquor.

[0031] To control the mother liquor outflow temperature at the refrigerant outlet 202 of the glass heat exchanger 2, the end of the second connecting pipe 8 away from the refrigerant outlet 202 is connected to the end of the liquid inlet 101 away from the central circulating tubular evaporator 1. A temperature detection structure for detecting the mother liquor temperature is provided between the second connecting pipe 8 and the liquid inlet 101. The temperature detection structure is a temperature sensor 6, which is fixedly connected between the second connecting pipe 8 and the liquid inlet 101. The temperature sensor 6 can detect the temperature of the mother liquor flowing out from the refrigerant outlet 202 of the glass heat exchanger 2, so that the control device can control the electronically controlled regulating valve 5 to control the mother liquor flow rate. Combined with the control part of the central circulating tubular evaporator 1 that adjusts the steam feed rate according to the liquid temperature, the flow rate of the mother liquor entering the glass heat exchanger 2 can be accurately adjusted to ensure that the flow rate of the refrigerant mother liquor meets the optimal heat exchange efficiency and process requirements.

[0032] Working principle: In this embodiment, the outlet 103 is connected to the extraction device for the subsequent ethyl maltol mother liquor concentrate, and the central circulating tubular evaporator 1 has a commercially available control component that adjusts the steam feed rate based on the feed liquid temperature. During use, the mother liquor flows into the refrigerant inlet 201 of the glass heat exchanger 2 through the mother liquor pipe 4, and the electronically controlled regulating valve 5 precisely controls the mother liquor flow rate. After entering the glass heat exchanger 2, the mother liquor acts as a refrigerant and exchanges heat with the methanol vapor from the top steam pipe 3 of the central circulating tubular evaporator 1 (which enters through the heat exchanger steam inlet 203 at the top of the glass heat exchanger 2). The methanol vapor is condensed into a methanol solution upon cooling and flows into the methanol receiving tank for collection through the condensate outlet 204 of the glass heat exchanger. Meanwhile, the mother liquor, which serves as the refrigerant, absorbs heat and its temperature rises. The temperature is monitored in real time by the temperature sensor 6 installed at the refrigerant outlet 202 of the glass heat exchanger 2, and the outlet mother liquor temperature is controlled between 25-35℃. The mother liquor after heat exchange flows out from the refrigerant outlet 202 of the glass heat exchanger 2 and enters the central circulating tubular evaporator 1 through the liquid inlet 101.

[0033] In the central circulating tubular evaporator 1, steam is introduced through the evaporator steam inlet 102 to further heat the mother liquor, ensuring that the remaining methanol in the mother liquor is fully evaporated and guaranteeing the methanol recovery effect. The central circulating tubular evaporator 1 automatically adjusts the steam feed rate according to the feed liquid temperature to maintain a suitable feed liquid temperature and achieve a continuous and stable evaporation process. The mother liquor after methanol evaporation flows out from the outlet 103 of the central circulating tubular evaporator 1 and is transported to the extraction unit for subsequent extraction and recovery of ethyl maltol. The flexible hose effectively buffers vibrations and displacements that may occur during unit operation, ensuring normal operation of the packaging unit. The high-density polyethylene corrugated pipe effectively buffers vibrations and displacements during unit operation due to its expansion and contraction characteristics, while also ensuring the sealing of connections. Even under long-term exposure to acidic mother liquor and other substances, it maintains a good connection, guaranteeing normal unit operation. The electrically controlled regulating valve 5 is fixedly connected between the first connecting pipe 7 and the mother liquor pipe 4. The valve is used for precise control of the mother liquor flow rate. The temperature sensor 6 detects the temperature of the mother liquor flowing from the refrigerant outlet 202 of the glass heat exchanger 2, allowing the control unit to control the valve 5 to regulate the mother liquor flow rate. Combined with the control section of the central circulating tubular evaporator 1 that adjusts the steam feed rate based on the liquid temperature, the flow rate of the mother liquor entering the glass heat exchanger 2 can be precisely adjusted, ensuring that the refrigerant mother liquor flow rate meets the optimal heat exchange efficiency and process requirements.

[0034] Finally, it should be noted that the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A device for continuous recovery of methanol from an ethyl maltol solution, characterized by: The utility model provides a central circulation pipe evaporator (1), glass heat exchanger (2), flow control device and mother liquor providing device, the central circulation pipe evaporator (1) left wall from top to bottom is fixedly connected with liquid inlet (101) and steam condensate outlet (104) in proper order, the central circulation pipe evaporator (1) right wall is fixedly connected with evaporator steam inlet (102), the central circulation pipe evaporator (1) upper and lower ends are fixedly connected with steam pipeline (3) and liquid outlet (103) respectively, glass heat exchanger (2) left and right sides are fixedly connected with refrigerant inlet (201) and refrigerant outlet (202) respectively, glass heat exchanger (2) upper and lower ends are fixedly connected with heat exchanger steam inlet (203) and condensate outlet (204) respectively, refrigerant inlet (201) and refrigerant outlet (202) are connected between one end in glass heat exchanger (2) interior through heat exchange coil (205), refrigerant inlet (201) and refrigerant outlet (202) are fixedly connected with first connecting pipe (7) and second connecting pipe (8) respectively through a group of soft connection structure far from glass heat exchanger (2) one end.

2. The apparatus for continuous recovery of methanol from ethyl maltol solution according to claim 1, characterized in that: The first connecting pipe (7) is connected with the mother liquor pipeline (4) far from the refrigerant inlet (201), the flow control device for controlling the flow of mother liquor is arranged between the first connecting pipe (7) and the mother liquor pipeline (4), the second connecting pipe (8) is connected with the liquid inlet (101) far from the central circulation pipe evaporator (1) far from the refrigerant outlet (202) one end, the temperature detection structure for detecting the temperature of mother liquor is arranged between the second connecting pipe (8) and the liquid inlet (101).

3. The apparatus for continuous recovery of methanol from an ethyl maltol solution according to claim 2, wherein: The soft connection structure includes two groups of first flange (9), second flange (10), two groups of first flange (9) are fixedly connected on the one end of the first connecting pipe (7) far from the mother liquor pipeline (4) and the one end of the second connecting pipe (8) far from the liquid inlet (101) respectively, the first flange (9), second flange (10) are fixedly connected with the hose between opposite sides, the hose is fixedly connected with the first flange (9) through the third flange (11), the hose is fixedly connected with the second flange (10) through the fourth flange (12), the hose is composed of inner tube (14) and outer tube (13) wrapped in the outer wall of inner tube (14).

4. The apparatus for continuous recovery of methanol from an ethyl maltol solution according to claim 3, wherein: The inner tube (14) is a high-density polyethylene bellows, and the outer tube (13) is a stainless steel bellows.

5. The apparatus for continuous recovery of methanol from an ethyl maltol solution according to claim 2, wherein: The flow control device is an electric control regulating valve (5), which is fixedly connected between the first connecting pipe (7) and the mother liquor pipeline (4).

6. The apparatus for continuous recovery of methanol from an ethyl maltol solution according to claim 2, wherein: The temperature detection structure is a temperature sensor (6), which is fixedly connected between the second connecting pipe (8) and the liquid inlet (101).

7. The apparatus for continuous recovery of methanol from an ethyl maltol solution according to claim 2, wherein: The end of the mother liquor pipeline (4) far from the flow control device is connected with the mother liquor providing device.

Images