A methanol distillation apparatus

Abstract

This invention relates to a methanol distillation apparatus. The distillation column contains several circular, horizontally arranged trays arranged from top to bottom. Each tray includes a central diffuser zone and surrounding channel zones. The diffuser zone has uniformly distributed ventilation holes, allowing methanol gas from below the tray to pass through. A baffle is positioned above the diffuser zone to temporarily block methanol gas rising from it. A liquid supply pipe is connected to the center of the baffle, guiding liquid flowing down from the upper tray to the lower tray. The channel zones have several concentrically arranged storage tanks from the inside out, allowing liquid flowing down from the diffuser zone to enter the storage tanks. Each storage tank has side walls, with a cavity between adjacent walls. This cavity is closed at the top and open at the bottom, allowing methanol gas from below the tray to enter the cavity. Several through-holes are provided on the tank walls, allowing methanol gas from the cavity to enter the storage tanks and contact the liquid inside. The outermost storage tank of the tray is connected to a liquid supply pipe.

Description

Technical Field

[0001] This invention belongs to the field of methanol distillation technology, and specifically relates to a methanol distillation apparatus. Background Technology

[0002] Methanol is a crucial raw material in the chemical, industrial, and medical fields, used to produce a variety of organic compounds. The yield of pure methanol is often used as a benchmark for a country's chemical and industrial capabilities. Current processes involve distilling crude methanol to obtain high-purity methanol. Regarding methanol distillation, those skilled in the art have consistently focused on improving distillation efficiency to achieve higher methanol purity. Summary of the Invention

[0003] To address the aforementioned problems, this invention provides a methanol distillation apparatus, including a distillation column. The column contains several circular, horizontally arranged trays arranged from top to bottom. Each tray includes a central diffuser zone and surrounding channel zones. The diffuser zone has uniformly distributed ventilation holes to allow methanol gas below the tray to pass through it. A baffle is positioned above the diffuser zone to temporarily block methanol gas rising from it. A liquid supply pipe is connected to the center of the baffle to guide liquid flowing down from the upper tray to the lower tray.

[0004] The channel zone has several concentrically arranged liquid storage tanks from the inside to the outside. The liquid flowing down from the diffuser zone can flow into the liquid storage tanks. The liquid storage tanks have tank walls on both sides, and there is a cavity between two adjacent tank walls. The top of the cavity is closed and the bottom is open, allowing methanol gas below the tray to enter the cavity. The tank walls have several through holes, and the methanol gas in the cavity can enter the liquid storage tank through the through holes and come into contact with the liquid in the liquid storage tank. The outermost liquid storage tank of the tray is connected to the liquid supply pipe.

[0005] Optionally, the distillation column is cylindrical, with a reboiler connected to the bottom and a drain outlet at the bottom for discharging waste liquid; a raw material inlet is located on the side of the column for inputting crude methanol raw material; and a product outlet and a gas inlet are located at the top of the column for discharging refined methanol product and inputting steam, respectively.

[0006] Optionally, both the diffuser and the baffle are conical in shape, with a smaller top and a larger bottom. There is a gap between the diffuser and the baffle. The diffuser, the baffle, and all the liquid storage tanks are concentrically arranged. The baffle is a solid plate without holes, which can temporarily block the gas rising from the diffuser. The upper surface of the diffuser and the lower surface of the baffle are both smooth surfaces, which facilitates the liquid to flow down along these two surfaces respectively.

[0007] Further optionally, the liquid supply pipe vertically penetrates the baffle, with the bottom end of the liquid supply pipe open and located above the center of the diffusion zone, so as to supply liquid to the diffusion zone; the liquid supply pipe is provided with several openings at the position corresponding to the lower surface of the baffle, so as to supply liquid to the lower surface of the baffle.

[0008] Further optionally, the plurality of openings are evenly arranged along the circumference of the liquid supply pipe, and a horizontal circular liquid guide plate is provided below the opening. The liquid guide plate extends toward the lower surface of the baffle, and there is a very small gap between the outer edge of the liquid guide plate and the lower surface of the baffle, so that the liquid flowing out from each opening is intercepted by the liquid guide plate and guided to the baffle, and then left along the lower surface of the baffle.

[0009] Optionally, for two adjacent inner and outer rings of liquid storage tanks, there is a cavity between the outer wall of the inner ring liquid storage tank and the inner wall of the outer ring liquid storage tank. The tops of these two tank walls extend towards each other and are joined together, so that the top of the cavity is sealed, preventing the gas entering the cavity from directly diffusing upwards and escaping.

[0010] The cavity is equipped with several liquid channels, which allow the liquid in the inner ring liquid storage tank to flow into the outer ring liquid storage tank through the liquid channels, until it flows to the outermost ring liquid storage tank.

[0011] Alternatively, several liquid channels are evenly distributed along the circumference of the corresponding cavity, the height of the liquid channels is less than the height of the corresponding cavity, and the liquid channels are located at the upper part of the corresponding cavity, so that the liquid in the upper part of the inner ring liquid storage tank flows into the outer ring liquid storage tank through the liquid channels.

[0012] Optionally, the liquid channel is side-sealed, which isolates the liquid channel from the space inside the cavity, preventing liquid from leaking out of the tray from the cavity; the two ends of the liquid channel are respectively connected to the outer wall of the inner ring liquid storage tank and the inner wall of the outer ring liquid storage tank.

[0013] Optionally, a number of through holes are evenly provided in the lower middle part of the tank wall, so that the gas rising below the tray can enter the liquid storage tanks on both sides of the cavity through the through holes.

[0014] Optionally, a liquid collection trough is provided on the outer edge of the tray to collect the liquid overflowing from the channel flow zone. Several connecting pipes are provided at the bottom of the liquid collection trough, and the ends of the connecting pipes are connected in parallel to the top of the liquid supply pipe to guide the liquid into the liquid supply pipe. Attached Figure Description

[0015] Figure 1 Schematic diagram of the tower plate structure;

[0016] Figure 2 This is a side view of the tray;

[0017] Figure 3 This is a schematic diagram of a liquid storage tank.

[0018] In the attached diagram, 1-diffusion zone, 2-channel zone, 3-vent hole, 4-through hole, 5-baffle, 6-liquid supply pipe, 7-liquid storage tank, 8-cavity, 9-opening, 10-liquid guide plate, 11-liquid channel. Detailed Implementation

[0019] This embodiment provides a methanol distillation apparatus, including a distillation column, the interior of which is provided with several trays arranged from top to bottom, such as... Figures 1-3 As shown, the tray is circular and horizontally arranged. The tray includes a central diffuser zone 1 and surrounding channel zones 2. The diffuser zone 1 is evenly covered with vent holes 3, allowing methanol gas below the tray to pass through the diffuser zone 1. A baffle 5 is provided above the diffuser zone 1 to temporarily block the methanol gas rising from the diffuser zone 1. The center of the baffle 5 is connected to a liquid supply pipe 6, which guides the liquid flowing down from the upper tray to the lower tray.

[0020] The channel zone 2 has several concentrically arranged liquid storage tanks 7 from the inside to the outside. The liquid flowing down from the diffuser zone 1 can flow into the liquid storage tanks 7. The liquid storage tanks 7 have tank walls on both sides, and there is a cavity 8 between two adjacent tank walls. The top of the cavity 8 is closed and the bottom is open, allowing methanol gas below the tray to enter the cavity 8. Several through holes 4 are provided on the tank walls, and the methanol gas in the cavity 8 can enter the liquid storage tanks 7 through the through holes 4 and come into contact with the liquid in the liquid storage tanks 7. The outermost ring of liquid storage tanks of the tray is connected to the liquid supply pipe 6.

[0021] Optionally, the distillation column is cylindrical, with a reboiler connected to the bottom and a drain outlet at the bottom for discharging waste liquid. A feed inlet is located on the side of the column for inputting crude methanol feedstock. The top of the column has a product outlet and a gas inlet for discharging refined methanol product and inputting steam, respectively. The basic structure of the distillation column of this invention is the same as that of existing methanol distillation columns, and a heat exchanger can be connected to the top of the column to provide steam.

[0022] Optionally, two adjacent trays are connected to the inner walls of opposite sides of the distillation column, with one side of the tray connected to the inner wall of the tray and the other side suspended with a gap between it and the inner wall of the opposite column.

[0023] Optionally, both the diffuser 1 and the baffle 5 are conical in shape, with a smaller top and a larger bottom. There is a gap between the diffuser 1 and the baffle 5. The diffuser 1, the baffle 5, and all the liquid storage tanks 7 are concentrically arranged. The baffle 5 is a solid plate without holes, which can temporarily block the gas rising from the diffuser 1. The upper surface of the diffuser 1 and the lower surface of the baffle 5 are both smooth surfaces, which facilitates the liquid to flow down along these two surfaces respectively.

[0024] Optionally, the liquid supply pipe 6 vertically penetrates the baffle 5, with the bottom end of the liquid supply pipe 6 open and positioned above the center of the diffusion area 1, enabling it to supply liquid to the diffusion area 1; the liquid supply pipe 6 has several openings 9 corresponding to the lower surface of the baffle 5, enabling it to supply liquid to the lower surface of the baffle 5.

[0025] Optionally, the plurality of openings 9 are evenly arranged along the circumference of the liquid supply pipe 6, and a horizontal circular liquid guide plate 10 is provided below the openings 9. The liquid guide plate 10 extends toward the lower surface of the baffle 5, and there is a very small gap between the outer edge of the liquid guide plate 10 and the lower surface of the baffle 5, so that the liquid flowing out from each opening 9 is intercepted by the liquid guide plate 10 and guided to the baffle 5, and then left along the lower surface of the baffle 5.

[0026] The liquid supply pipe 6 guides the liquid flowing down from the previous tray to the next adjacent tray. Specifically, the liquid supply pipe 6 is a hollow cylindrical pipe through which liquid flows. When the liquid reaches the opening 9, some of the liquid flows out from several openings 9, then flows along the guide plate 10 to a position near its own center on the lower surface of the baffle 5. Then, the liquid flows evenly down the lower surface of the baffle 5, forming a liquid film on the lower surface of the baffle 5. The remaining liquid in the liquid supply pipe 6 flows to the center of the diffuser zone 1 (i.e., the highest point of the diffuser zone 1), then flows evenly down the upper surface of the diffuser zone 1, also forming a liquid film on the upper surface of the diffuser zone 1.

[0027] A portion of the methanol gas rising from the next tray moves to the area below the diffuser zone 1. The conical shape of the diffuser zone 1 facilitates the collection of this portion of methanol gas. The gas passes through the vent 3 into the diffuser zone 1 and comes into contact with the liquid film on the upper surface of the diffuser zone 1, where impurities in the gas dissolve in the liquid. The gas then continues to rise, encountering the liquid film on the lower surface of the baffle 5, where gas-liquid contact mass transfer occurs again, further purifying the methanol gas. The conical design of the baffle 5 and the diffuser zone 1 allows downward-flowing liquid films to form on both surfaces, while also converging the rising methanol gas. Due to the obstruction effect of the baffle 5, the gas is prevented from rising too quickly and leaving the tray. Instead, the gas comes into contact with the liquid film on the lower surface of the baffle 5 again, allowing mass transfer and further separation of impurities in the gas. At the same time, the gas moves downward along the baffle 5, then overflows from the bottom edge of the baffle 5 before continuing to rise.

[0028] The liquid flowing down from the baffle 5 and the diffuser 1 flows into the innermost ring of the liquid storage tank. The innermost ring of the liquid storage tank has no tank wall or a very low tank wall, allowing the liquid from the diffuser 1 to flow naturally into the liquid storage tank.

[0029] Optionally, for two adjacent inner and outer rings of liquid storage tanks, there is a cavity 8 between the outer wall of the inner ring liquid storage tank and the inner wall of the outer ring liquid storage tank. The tops of these two tank walls extend towards each other and are joined together, so that the top of the cavity 8 is sealed, preventing the gas entering the cavity 8 from directly diffusing upward and escaping.

[0030] The cavity 8 is provided with several liquid channels 11, so that the liquid in the inner ring liquid storage tank can flow into the outer ring liquid storage tank through the liquid channels 11, until it flows to the outermost ring liquid storage tank.

[0031] Alternatively, several liquid channels 11 are evenly distributed along the circumference of the corresponding cavity 8. The height of the liquid channels 11 is less than the height of the corresponding cavity 8. The liquid channels 11 are located at the upper part of the corresponding cavity 8, so that the liquid in the upper part of the inner ring liquid storage tank flows into the outer ring liquid storage tank through the liquid channels 11.

[0032] Optionally, the side of the liquid channel 11 is closed, so that the liquid channel 11 is isolated from the space inside the cavity 8, preventing liquid from leaking out of the tray from the cavity 8; the two ends of the liquid channel 11 are respectively connected to the outer wall of the inner ring liquid storage tank and the inner wall of the outer ring liquid storage tank, so that the liquid channel 11 connects the inner and outer ring liquid outlet tanks.

[0033] Alternatively, a number of through holes 4 are evenly provided in the lower middle part of the tank wall, so that the gas rising below the tower plate can enter the liquid storage tanks on both sides of the cavity 8 through the through holes 4.

[0034] The liquid flowing down along baffle 5 and diffuser zone 1 first enters the innermost ring of storage tanks, and then gradually enters each storage tank from the inside out, until reaching the outermost ring. As the liquid in the inner ring storage tanks increases, it can flow through liquid channel 11 to the outer ring storage tanks, ensuring that the liquid in channel zone 2 is constantly renewed. Gas below the tray enters the storage tank through the through-holes 4 on the tank wall, directly entering the liquid inside the storage tank, undergoing mass transfer with the liquid, removing impurities, and then overflowing from the storage tank before continuing to rise.

[0035] Of the gas rising from the lower tray, part rises from channel zone 2, and another part flows out from the bottom edge of baffle 5 and then rises. In short, the gas rising from the lower tray mainly rises from channel zone 2. This results in uneven distribution of the rising gas flow across the cross-section of the distillation column. The tray structure of this invention can solve the above problem because the lower surface of the diffuser zone 1 is conical, which has the function of converging and gathering the gas flow, and can balance the gas intake of the tray to a certain extent.

[0036] The tray of this invention features a zoned design, divided from the inside out. The liquid source for the tray is a supply pipe 6, which supplies liquid to the diffuser zone 1 and baffle 5. The liquid forms a film and flows down. Gas rising from the diffuser zone 1 passes through the liquid film of the diffuser zone 1 and baffle 5, undergoing two gas-liquid mass transfers before leaving baffle 5, thus improving the separation effect. The liquid in the diffuser zone 1 continues to flow through each storage tank. Gas below the tray enters each storage tank through the through-hole 4, undergoing gas-liquid contact mass transfer. Because the gas is directly input into the liquid and then overflows from the liquid surface, the mass transfer process is relatively thorough. The kinetic energy of the gas flow can disturb the liquid and also promote gas-liquid contact. After flowing through each storage tank, the liquid in the channel zone 2 overflows from the outside of the tray.

[0037] Because the liquid level in the storage tank is not very high, gas can enter through hole 4, but liquid will not leak out.

[0038] Optionally, a liquid collection trough is provided on the outer edge of the tray to collect the liquid overflowing from the channel flow zone 2. Several connecting pipes are provided at the bottom of the liquid collection trough, and the ends of the connecting pipes are connected in parallel to the top of the liquid supply pipe 6 to guide the liquid into the liquid supply pipe 6.

Claims

1. A methanol distillation apparatus, comprising a distillation column, characterized in that, The distillation column has several circular, horizontally arranged trays arranged from top to bottom. Each tray includes a central diffuser zone and surrounding channel zones. The diffuser zone is densely covered with evenly distributed vents to allow methanol gas from below the tray to pass through it. A baffle is installed above the diffuser zone to temporarily block the methanol gas rising from it. A liquid supply pipe is connected to the center of the baffle to guide the liquid flowing down from the upper tray to the lower tray. The channel zone has several concentrically arranged liquid storage tanks from the inside to the outside. Liquid flowing down from the diffuser zone can flow into the liquid storage tanks. The liquid storage tanks have tank walls on both sides, and there is a cavity between two adjacent tank walls. The top of the cavity is closed and the bottom is open, allowing methanol gas below the tray to enter the cavity. The tank walls have several through holes, and the methanol gas in the cavity can enter the liquid storage tank through the through holes and come into contact with the liquid in the liquid storage tank. The outermost ring of liquid storage tanks of the tray is connected to the liquid supply pipe. Both the diffuser and the baffle are conical in shape, with a smaller top and a larger bottom. There is a gap between the diffuser and the baffle. The diffuser, the baffle, and all the liquid storage tanks are concentrically arranged. The baffle is a solid plate without holes, which can temporarily block the gas rising from the diffuser. The upper surface of the diffuser and the lower surface of the baffle are both smooth surfaces, which facilitates the liquid to flow down along these two surfaces respectively. The liquid supply pipe penetrates the baffle vertically, with its bottom end open and positioned above the center of the diffusion zone, allowing it to supply liquid to the diffusion zone. The liquid supply pipe has several openings corresponding to the lower surface of the baffle, enabling it to supply liquid to the lower surface of the baffle. The plurality of openings are evenly arranged along the circumference of the liquid supply pipe. Below the openings is a horizontal circular liquid guide plate that extends toward the lower surface of the baffle. There is a very small gap between the outer edge of the liquid guide plate and the lower surface of the baffle, so that the liquid flowing out from each opening is intercepted by the liquid guide plate and guided to the baffle, and then flows down along the lower surface of the baffle.

2. The methanol distillation apparatus according to claim 1, characterized in that, The distillation column is cylindrical, with a reboiler connected to the bottom and a drain outlet at the bottom for discharging waste liquid. A raw material inlet is located on the side of the column for feeding crude methanol feedstock. A product outlet and a gas inlet are located at the top of the column for discharging refined methanol product and feeding steam, respectively.

3. The methanol distillation apparatus according to claim 1, characterized in that, For two adjacent inner and outer rings of liquid storage tanks, there is a cavity between the outer wall of the inner ring liquid storage tank and the inner wall of the outer ring liquid storage tank. The tops of these two tank walls extend towards each other and are joined together, so that the top of the cavity is sealed, preventing the gas entering the cavity from directly diffusing upwards and escaping. The cavity is equipped with several liquid channels, which allow the liquid in the inner ring liquid storage tank to flow into the outer ring liquid storage tank through the liquid channels, until it flows to the outermost ring liquid storage tank.

4. The methanol distillation apparatus according to claim 3, characterized in that, Several liquid channels are evenly distributed along the circumference of the corresponding cavities. The height of the liquid channels is less than the height of the corresponding cavities, and the liquid channels are located at the top of the corresponding cavities, so that the liquid in the upper part of the inner ring liquid storage tank flows into the outer ring liquid storage tank through the liquid channels.

5. The methanol distillation apparatus according to claim 4, characterized in that, The side of the liquid channel is closed, which isolates the liquid channel from the space inside the cavity and prevents the liquid from leaking out of the tray from the cavity; the two ends of the liquid channel are respectively connected to the outer wall of the inner ring liquid storage tank and the inner wall of the outer ring liquid storage tank.

6. The methanol distillation apparatus according to claim 4, characterized in that, The lower middle part of the tank wall is uniformly provided with several through holes, so that the gas rising below the tower plate can enter the liquid storage tanks on both sides of the cavity through the through holes.

7. The methanol distillation apparatus according to claim 1, characterized in that, The outer edge of the tray is provided with a liquid collection trough for collecting the liquid overflowing from the channel flow zone. Several connecting pipes are provided at the bottom of the liquid collection trough, and the ends of the connecting pipes are connected in parallel to the top of the liquid supply pipe to guide the liquid into the liquid supply pipe.

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