Methylcyclohexanediamine production waste liquid treatment equipment and process

Abstract

The present application relates to wastewater treatment technical field, specifically provide a kind of methylcyclohexane diamine production waste liquid treatment equipment and process, equipment includes heat exchanger, gas-liquid separator, fluid conveying assembly and annular flow guide, heat exchanger has mutually isolated and can be mutually heat exchange first fluid passage and second fluid passage;Gas-liquid separator is located above heat exchanger.The present application by making waste liquid in the outlet direction of gas-liquid separator upward, and annular flow guide is set above the outlet of waste liquid, so waste liquid flows out upward and boils after decompression, under the flow guiding effect of annular flow guide, gas phase and liquid phase are dispersed, reduce the interaction between gas phase and liquid phase, so compared with the technical scheme of waste liquid outlet direction downward in prior art, the distance of gas phase downward movement will be shorter, so it is advantageous to improve the gas-liquid separation efficiency of waste liquid.

Description

Technical Field

[0001] This invention relates to the field of wastewater treatment technology, and in particular to a treatment device and process for wastewater from the production of methylcyclohexanediamine. Background Technology

[0002] The waste liquid from methylcyclohexanediamine production mainly originates from the dehydration process during production. The waste liquid contains an extremely high percentage of water, typically greater than 99%, while organic amines account for less than 1%.

[0003] For this type of wastewater, current engineering practices often employ a series process of stripping ammonia removal followed by MVR (Medium-Volume Recirculation) evaporation. Specifically, stripping is used to remove most of the free ammonia / low-boiling amines, and then the stripped wastewater is concentrated through MVR evaporation. Practical experience has shown that this process significantly reduces the ammonia nitrogen load in the condensate.

[0004] The detailed flow of the MVR circulating evaporation process is as follows: The treated waste liquid first enters the preheater, where it is preheated. The preheated waste liquid then enters the tube side of a tubular heat exchanger, where it undergoes further heat exchange with the high-temperature steam in the shell side. Next, the waste liquid flows upwards into a gas-liquid separator. In the gas-liquid separator, the waste liquid is depressurized and boils, separating the resulting steam and concentrate. The steam is discharged upwards, pressurized and heated by a compressor, and then returned to the shell side of the tubular heat exchanger to heat the waste liquid in the tube side. The steam discharged from the shell side is then discharged from the system after heat recovery in the preheater. The concentrate flows downwards and is returned to the tube side of the tubular heat exchanger for reheating. The heated concentrate then returns to the gas-liquid separator for further separation until the concentrate reaches the target concentration, at which point it is discharged from the system. The subsequent concentration treatment process for new waste liquid is the same as described above.

[0005] In the aforementioned cycle, the waste liquid fed into the gas-liquid separator has a certain initial velocity. When the opening of the waste liquid feed pipe is downward, the vapor in the waste liquid will move downward with the liquid until its velocity decreases to zero before moving upward, resulting in low separation efficiency. When the opening of the waste liquid feed pipe is upward, the waste liquid will move upward with the vapor under the action of inertial force, which will worsen the separation effect between vapor and waste liquid. Summary of the Invention

[0006] Therefore, it is necessary to provide a methylcyclohexanediamine production waste liquid treatment equipment and process to address the problems existing in current wastewater treatment equipment, in order to solve the problems of low separation efficiency and poor separation effect of liquid substances and vapors in the waste liquid when the existing wastewater treatment equipment is treating the waste liquid.

[0007] The above objectives are achieved through the following technical solutions: A wastewater treatment device for methylcyclohexanediamine production includes: A heat exchanger having a first fluid channel and a second fluid channel that are mutually isolated but capable of exchanging heat with each other; The gas-liquid separator is located above the heat exchanger; A fluid transport assembly for transporting waste liquid to a gas-liquid separator; for circulating the waste liquid between a first fluid channel and the gas-liquid separator, with the outlet direction of the waste liquid in the gas-liquid separator facing upwards; for transporting the gas phase in the gas-liquid separator to a second fluid channel; and for transporting waste liquid with a concentration increased to a target solubility to a storage container. An annular guide element, located inside the gas-liquid separator, is configured with a downwardly inclined guide surface to cause the gas phase and waste liquid to be radially dispersed and move downward along the guide surface.

[0008] Furthermore, the fluid transport assembly includes a first pipe, a second pipe, a third pipe, and a fourth pipe. The inlet of the first pipe has a first branch and a second branch. The first branch is connected to the outlet of the first fluid channel, and the second branch is connected to the main input end of the waste liquid. The outlet of the first pipe is connected to a gas-liquid separator, and the outlet opening of the first pipe faces upward. The inlet of the second pipe is located inside the gas-liquid separator, and the inlet height is lower than the outlet height of the first pipe. The outlet of the second pipe is connected to the inlet of the first fluid channel. The inlet of the third pipe is connected to the top of the gas-liquid separator, and the outlet is connected to the inlet of the second fluid channel. The fourth pipe is connected between the bottom of the gas-liquid separator and the storage container, and is used to transport the waste liquid with the concentration increased to the target concentration to the storage container.

[0009] Furthermore, the annular guide includes a support cage, a circular plate, a conical guide section, and a support ring. The support cage is fixed to the upper end of the first pipe, the circular plate is fixed to the upper end of the support cage, the support ring is coaxial with the circular plate and is located below the circular plate, and the small end of the conical guide section is fixed to the circular plate and the large end is fixed to the support ring.

[0010] Furthermore, the waste liquid treatment equipment for methylcyclohexanediamine production also includes a siphon hood, which is located inside the gas-liquid separator and fixed to the outer periphery of the first pipe. The siphon hood is open at the bottom and sealed at the top; Furthermore, the lower opening height of the siphon hood is less than the upper opening height of the second pipe.

[0011] Furthermore, the tapered guide section is made of an elastic material; An adjustment assembly is provided between the support ring and the siphon shroud to adjust the taper of the tapered guide section; Furthermore, the taper of the conical guide section is negatively correlated with the volume of waste liquid in the gas-liquid separator.

[0012] Furthermore, the adjustment assembly includes an adjustment cylinder, an adjustment plug, a connecting rod, an elastic element, and a deflector. The adjustment cylinder is embedded in the upper part of the siphon shroud, and both ends of the adjustment cylinder are open. The adjustment plug is slidably connected coaxially inside the adjustment cylinder to divide the interior of the adjustment cylinder into upper and lower parts. The upper part of the connecting rod is fixedly connected to the support ring, and the lower part is fixedly connected coaxially to the adjustment plug. The elastic element is sleeved on the outside of the connecting rod, and both ends of the elastic element are connected to the adjustment plug and the adjustment cylinder, respectively. The elastic element is specifically a compression spring, and the upper end of the compression spring is fixed to the adjustment plug, and the lower end is fixed to the bottom of the adjustment cylinder. The deflector is coaxially fixed to the connecting rod, and the deflector is located above the adjustment cylinder.

[0013] Furthermore, the heat exchanger is a tubular heat exchanger.

[0014] Furthermore, a transparent window is provided on the side of the gas-liquid separator.

[0015] Furthermore, a support platform is provided on the outside of the gas-liquid separator to support it.

[0016] A process for treating waste liquid from the production of methylcyclohexanediamine, using the aforementioned waste liquid treatment equipment, includes the following steps: S100. Add the target volume of waste liquid into the gas-liquid separator; S200, causing the waste liquid to circulate between the gas-liquid separator and the first fluid channel, and causing the gas phase in the gas-liquid separator to be transported to the second fluid channel; S300: When the concentration of waste liquid in the gas-liquid separator increases to the target concentration, the waste liquid is transported to the storage container. S400, repeat S100-S300 until all the waste liquid in the current batch is sent into the gas-liquid separator.

[0017] The beneficial effects of this invention are: 1. This invention, by aligning the outlet of the waste liquid in the gas-liquid separator with an upward direction and installing an annular guide above the outlet, allows the waste liquid to flow upward and boil due to pressure reduction. Under the guidance of the annular guide, the gas and liquid phases disperse, reducing their interaction. Furthermore, as the gas phase moves downward along the guide, its kinetic energy is depleted. Therefore, the velocity at which the gas phase separates from the guide surface is significantly lower than the downward velocity of the gas phase in the downward-opening technical solution. Compared to the prior art where the waste liquid outlet is downward, the downward distance of the gas phase is shorter, thus improving the gas-liquid separation efficiency of the waste liquid.

[0018] 2. The present invention is equipped with an annular guide, which guides the liquid phase and gas phase to disperse and move downward. In this way, the liquid phase will not move upward with the gas phase under its own inertial force. Therefore, compared with the existing technology where the waste liquid outlet direction is upward, the present invention is beneficial to improving the gas-liquid separation effect of waste liquid.

[0019] 3. This invention incorporates a siphon hood. Under the siphon effect, as long as the liquid level is higher than the lower end face of the siphon hood, the waste liquid in the gas-liquid separator can overcome its own gravity and flow upwards. Therefore, during the discharge of the waste liquid from the outlet of the second pipe, changes in liquid level will not affect the circulation pressure of the waste liquid, which is beneficial for maintaining the stability of the waste liquid's circulation flow. Furthermore, by incorporating the siphon hood, the amount of crystals entering the first pipe, second pipe, and first fluid channel can be reduced, which helps extend the service life of the first pipe, second pipe, and first fluid channel.

[0020] 4. This invention incorporates an adjustment component. When there is a large amount of waste liquid, the adjustment component maintains a small taper in the conical guide section. At this time, the resistance that the waste liquid ejected from the first pipe outlet needs to overcome is small. This means that the forced circulation pump needs to overcome less resistance to drive the waste liquid circulation, which helps extend the service life of the forced circulation pump. As the amount of waste liquid decreases, the adjustment component gradually increases the taper of the conical guide section. This increases the resistance that the waste liquid ejected from the first pipe outlet needs to overcome. This helps to prevent the waste liquid from crystallizing in the first pipe, second pipe, and first fluid channel through pressurization, thereby extending the service life of the first pipe, second pipe, and first fluid channel. Attached Figure Description

[0021] Figure 1 This is an overall schematic diagram of a waste liquid treatment device for the production of methylcyclohexanediamine according to the present invention; Figure 2 for Figure 1 Side view; Figure 3 for Figure 2 Sectional view of AA; Figure 4 for Figure 3 A magnified schematic diagram of the structure at point B in the middle; Figure 5 for Figure 2 Axonometric drawing of the middle AA section; Figure 6 for Figure 5 A magnified schematic diagram of the structure at point C; Figure 7 for Figure 1 Top view; Figure 8 for Figure 7 DD section view; Figure 9 for Figure 8 A magnified schematic diagram of the structure at point E in the middle; Figure 10 This is a schematic diagram illustrating the change in liquid level height difference within the siphon hood in a methylcyclohexanediamine production waste liquid treatment device according to the present invention.

[0022] in: 100. Heat exchanger; 200. Gas-liquid separator; 210. Transparent window; 310, First pipe; 311, First branch; 312, Second branch; 320, Second pipe; 330, Third pipe; 340, Fourth pipe; 350, Forced circulation pump; 400. Annular guide component; 410. Support cage; 420. Circular plate; 430. Conical guide section; 440. Support ring; 500. Siphon hood; 510. Support frame; 600, Adjustment component; 610, Adjustment cylinder; 620, Adjustment plug; 630, Connecting rod; 640, Elastic element; 650, Support frame; 660, Deflector. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below through embodiments and in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0024] The component designations used in this document, such as "first" and "second," are merely for distinguishing the described objects and do not have any sequential or technical meaning. The terms "connection" and "linkage" used in this invention, unless otherwise specified, include both direct and indirect connections (linkages). It should be understood that the terms "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are used only for the convenience of describing the invention and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as limiting the invention.

[0025] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "beneath" of the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0026] The following reference Figures 1-10 This invention describes a waste liquid treatment device for the production of methylcyclohexanediamine.

[0027] A waste liquid treatment device for methylcyclohexanediamine production includes a heat exchanger 100, a gas-liquid separator 200, a fluid conveying assembly, and an annular guide member 400. The heat exchanger 100 has a first fluid channel and a second fluid channel that are isolated from each other and capable of exchanging heat with each other. The gas-liquid separator 200 is located above the heat exchanger 100 and has a material chamber for containing waste liquid. The fluid conveying assembly is used to convey the waste liquid into the gas-liquid separator 200; to circulate the waste liquid between the first fluid channel and the gas-liquid separator 200, and to make the outlet direction of the waste liquid in the gas-liquid separator 200 face upward; to convey the gas phase in the gas-liquid separator 200 into the second fluid channel; and to convey the waste liquid with a concentration increased to a target solubility into a storage container. The annular guide member 400 is disposed in the gas-liquid separator 200 and configured to have a downwardly inclined guide surface, so that the gas phase and the waste liquid are radially dispersed and flow downward along the guide surface.

[0028] The waste liquid treatment process is the same as that of existing technologies. First, most of the free ammonia / low-boiling amines are removed through a stripping process. The stripped waste liquid is then transported into a gas-liquid separator 200 until the volume of the waste liquid in the gas-liquid separator 200 reaches the target volume.

[0029] Next, the waste liquid is circulated between the first fluid channel and the gas-liquid separator 200 via a fluid conveying assembly. During this process, the waste liquid evaporates and separates within the gas-liquid separator 200. The separated waste liquid is then conveyed to the first fluid channel via the fluid conveying assembly, while the separated gas phase is conveyed to the second fluid channel via the fluid conveying assembly. At this point, the waste liquid in the first fluid channel exchanges heat with the gas phase in the second fluid channel, heating the waste liquid and gradually increasing its temperature. The heated waste liquid is then conveyed back to the gas-liquid separator 200 via the fluid conveying assembly and flows upwards into the gas-liquid separator 200, where it continues to evaporate and separate. When the waste liquid in the first fluid channel absorbs heat to near boiling point, it does not boil due to the hydrostatic pressure of the liquid column within the gas-liquid separator 200, thus preventing crystallization and blockage of the heat exchanger 100. When the near-boiling waste liquid is conveyed to the material chamber of the gas-liquid separator 200 via the fluid conveying assembly, the waste liquid boils due to a sudden drop in static pressure, and a large amount of gas phase (high-temperature water vapor) is separated from the waste liquid. Since the outlet direction of the waste liquid in the gas-liquid separator 200 is upward, a small amount of waste liquid moves upward with the gas phase under the action of inertial force. Since the guide surface of the annular guide member 400 is inclined downward, the gas phase and a small amount of waste liquid move upward until they are blocked by the guide surface of the annular guide member 400. Then, they disperse radially along the guide surface and move downward.

[0030] In this process, the radial dispersion of both phases increases the dispersion of the gas and liquid (waste liquid) phases, reduces the interaction between them, and allows the gas phase to rise smoothly along a larger cross-section after detaching from the guide surface, while the liquid phase settles rapidly under gravity. Compared to existing technologies where the waste liquid outlet faces downwards, this improves the separation efficiency of the gas and liquid phases. The downward movement of both phases along the guide surface gives them downward velocity. When they detach from the guide surface, the liquid phase continues to move upwards under gravity, while the gas phase briefly decelerates downwards before rising again. Compared to existing technologies where the waste liquid outlet faces upwards, this significantly reduces the amount of liquid phase entrained in the gas phase discharged through the fluid transport assembly, thus improving the separation effect.

[0031] Once the concentration of the remaining waste liquid in the gas-liquid separator 200 increases to the target concentration, the waste liquid is transported to a storage container through a fluid transport assembly for harmless treatment of the concentrated waste liquid.

[0032] Next, similarly, the target volume of waste liquid is fed into the gas-liquid separator 200 again, and the above process is repeated until the current batch of waste liquid is completely treated. It should be noted that as the equipment operates, the volume of remaining waste liquid gradually decreases. If the volume of remaining waste liquid is less than the target volume, then all the remaining waste liquid can be fed into the gas-liquid separator 200.

[0033] In summary, compared with the existing technology where the waste liquid outlet is directed downwards, this invention, by directing the waste liquid outlet upwards within the gas-liquid separator 200 and providing an annular guide 400 above the outlet, allows the waste liquid to flow upwards and boil due to pressure reduction. Under the guidance of the annular guide 400, the gas and liquid phases disperse, reducing their interaction. Furthermore, as the gas phase moves downwards along the guide surface, its kinetic energy is depleted, resulting in a significantly lower velocity when separating from the guide surface compared to the downward-opening technology. This leads to a shorter downward distance for the gas phase, thus improving the gas-liquid separation efficiency. Compared to the existing technology where the waste liquid outlet is directed upwards, this invention, with its annular guide 400, guides the liquid and gas phases downwards, preventing the liquid phase from moving upwards with the gas phase due to its own inertia. Therefore, this invention further enhances the gas-liquid separation effect of the waste liquid.

[0034] In further embodiments, such as Figure 1 and Figure 3 As shown, the fluid transport assembly includes a first pipe 310, a second pipe 320, a third pipe 330, and a fourth pipe 340. The inlet of the first pipe 310 has a first branch port 311 and a second branch port 312, and valves are provided at both the first branch port 311 and the second branch port 312. The first branch port 311 is connected to the outlet of the first fluid channel, and the second branch port 312 is connected to the main input terminal of the waste liquid. The outlet of the first pipe 310 is connected to the gas-liquid separator 200, and the outlet opening of the first pipe 310 faces upward. The inlet of the second pipe 320 is located inside the gas-liquid separator 200. Furthermore, the inlet opening of the second pipe 320 faces upward, and the inlet height of the second pipe 320 is lower than the outlet height of the first pipe 310. The outlet of the second pipe 320 is connected to the inlet of the first fluid channel. The inlet of the third pipe 330 is connected to the top of the gas-liquid separator 200, and the outlet is connected to the inlet of the second fluid channel. The outlet of the fourth pipe 340 is connected to the bottom of the gas-liquid separator 200, and the inlet is connected to the storage container. It is used to transport waste liquid with increased concentration to the storage container. A valve switch is also provided at the fourth pipe 340. In the non-discharge state, the valve switch is in the closed state.

[0035] When adding waste liquid, open the valve switch at the first branch port 311 to transport the waste liquid in the main input end of the waste liquid to the gas-liquid separator 200 through the first branch port 311. After the volume of waste liquid in the gas-liquid separator 200 reaches the target volume, close the valve switch at the first branch port 311.

[0036] During waste liquid circulation, the valve switch at the second branch port 312 is opened, allowing the waste liquid flowing out of the first fluid channel outlet to enter the gas-liquid separator 200 through the first pipe 310. The waste liquid then flows upwards from the outlet of the first pipe 310 into the gas-liquid separator 200. Simultaneously, the waste liquid in the gas-liquid separator 200 enters the inlet of the first fluid channel through the second pipe 320, thus forming a waste liquid circulation loop. To provide the driving force for waste liquid circulation, the fluid conveying assembly also includes a forced circulation pump 350. The input end of the forced circulation pump 350 is connected to the outlet of the second pipe 320, and the output end of the forced circulation pump 350 is connected to the inlet of the first pipe 310. Through the driving action of the forced circulation pump 350, the waste liquid circulates between the first fluid channel and the gas-liquid separator 200.

[0037] The fluid circulation assembly also includes a compressor and a Roots pump. The input end of the Roots pump is connected to the outlet of the third pipe 330, the output end of the Roots pump is connected to the input end of the compressor, and the output end of the compressor is connected to the inlet of the second fluid passage.

[0038] After the compressor starts, it generates a negative pressure of about 300 mbar. At this time, the gas phase (water vapor) produced by evaporation is drawn in by the Roots pump, compressed and heated by the compressor, and then sent to the inlet of the second fluid channel to heat the waste liquid in the first fluid channel.

[0039] Once the waste liquid concentration in the gas-liquid separator 200 reaches the target concentration, open the valve switch at the fourth pipeline 340 to transfer the waste liquid in the gas-liquid separator 200 to the storage container. Discharge can be performed by gravity or by forced discharge using a pump.

[0040] In a further embodiment, such as Figures 4-6 As shown, the annular guide member 400 includes a support cage 410, a circular plate 420, a conical guide portion 430, and a support ring 440. The support cage 410 is fixed to the upper end of the first pipe 310, the circular plate 420 is fixed to the upper end of the support cage 410, the support ring 440 is coaxial with the circular plate 420 and is located below the circular plate 420, the small end of the conical guide portion 430 is fixed to the circular plate 420, and the large end is fixed to the support ring 440.

[0041] The purpose of the support cage 410 is to create a certain distance between the waste liquid outlet and the circular plate 420, thereby reducing the kinetic energy of the waste liquid when it comes into contact with the circular plate 420, and thus minimizing the shearing effect generated when the waste liquid comes into contact with the circular plate 420. The circular plate 420 is used to block the waste liquid and gas phase, changing their direction of movement. The conical guide section 430 is used to guide the gas phase and waste liquid, causing them to disperse circumferentially and move downwards. The support ring 440 is used to circumferentially limit the large end of the conical guide section 430.

[0042] It should be noted that, since the waste liquid from the production of methylcyclohexanediamine is alkaline, the materials of the support cage 410, circular plate 420, conical guide section 430, and support ring 440 should all be made of corrosion-resistant and alkali-resistant materials.

[0043] Understandably, as the concentration of waste liquid increases, the waste liquid level within the gas-liquid separator 200 gradually decreases, which is detrimental to the stable circulation of the waste liquid. To address this issue, in a further embodiment, such as... Figure 3 As shown, the waste liquid treatment equipment for methylcyclohexanediamine production also includes a siphon 500, which is located inside the gas-liquid separator 200 and fixed to the outer periphery of the first pipe 310; the lower end of the siphon 500 is open and the upper end is sealed; and the height of the lower end opening of the siphon 500 is less than the height of the upper end opening of the second pipe 320.

[0044] By setting up a siphon 500, under the action of air pressure, when the liquid level in the gas-liquid separator 200 is lower than the height of the lower end port of the siphon 500, the waste liquid in the gas-liquid separator 200 can overcome its own gravity and continuously flow upward from the lower end port of the siphon 500 until the waste liquid flows to the upper waste liquid inlet of the second pipe 320, and then flows out from the upper waste liquid inlet of the second pipe 320. During this process, changes in liquid level height will not affect the circulation pressure of the waste liquid, which is beneficial to maintaining the stability of the waste liquid circulation flow.

[0045] In addition, since the upper end of the siphon shroud 500 is sealed, the crystals that adhere to the annular guide 400 during waste liquid crystallization will not fall directly into the second pipe 320; while the crystals that fall to the bottom of the gas-liquid separator 200 need to overcome the gravity of the crystals before they can be drawn into the second pipe 320. Therefore, setting up the siphon shroud 500 also helps to significantly reduce the amount of crystals entering the second pipe 320, the first pipe 310 and the first fluid channel, which helps to extend the service life of the first pipe 310, the second pipe 320 and the heat exchanger 100.

[0046] It should also be noted that, such as Figure 5As shown, a support frame 510 is fixed on the outer peripheral surface of the siphon hood 500, and one end of the support frame 510 away from the siphon hood 500 is fixed on the inner peripheral wall of the gas-liquid separator 200.

[0047] In a further embodiment, such as Figure 6 As shown, the conical guide section 430 is made of elastic material; an adjustment component 600 is provided between the support ring 440 and the siphon shroud 500 to adjust the taper of the conical guide section 430; and the taper of the conical guide section 430 is negatively correlated with the volume of waste liquid in the gas-liquid separator 200.

[0048] When the volume of waste liquid in the gas-liquid separator 200 is large, the adjusting component 600 makes the taper of the conical guide section 430 smaller. At this time, the downward tilt angle of the conical guide section 430 is smaller, and the resistance that the waste liquid sprayed from the outlet of the first pipe 310 needs to overcome is smaller. That is, at this time, the resistance that the forced circulation pump 350 needs to overcome when driving the waste liquid to circulate is smaller, which is beneficial to extending the service life of the forced circulation pump 350.

[0049] As the volume of waste liquid in the gas-liquid separator 200 decreases, the regulating component 600 gradually increases the taper of the conical guide section 430. As the downward tilt angle of the conical guide section 430 gradually increases, the resistance that the waste liquid ejected from the waste liquid outlet of the first pipe 310 needs to overcome increases. At this time, the waste liquid pressure in the first pipe 310, the second pipe 320, and the first fluid channel of the heat exchanger 100 increases. This helps to prevent the waste liquid from crystallizing in the first pipe 310, the second pipe 320, and the first fluid channel by pressurization, thereby extending the service life of the first pipe 310, the second pipe 320, and the first fluid channel.

[0050] It should be noted that the preferred material for the conical guide section 430 is EPDM rubber. Tests have shown that the conical guide section 430 made of EPDM rubber can meet the usage requirements, and EPDM rubber has a high cost-performance ratio, meeting the requirements for economical use.

[0051] In a further embodiment, such as Figure 9 and Figure 10As shown, the adjustment assembly 600 includes an adjustment cylinder 610, an adjustment plug 620, a connecting rod 630, an elastic element 640, and a deflector umbrella 660. The adjustment cylinder 610 is embedded in the upper part of the siphon shroud 500, and both ends of the adjustment cylinder 610 are through. The adjustment plug 620 is slidably connected coaxially inside the adjustment cylinder 610 to divide the interior of the adjustment cylinder 610 into upper and lower parts. The upper part of the connecting rod 630 is fixedly connected to the support ring 440, and the lower part is fixedly connected coaxially to the adjustment plug 620. The elastic element 640 is sleeved on the outside of the connecting rod 630, and both ends of the elastic element 640 are connected to the adjustment plug 620 and the adjustment cylinder 610, respectively. The elastic element 640 is specifically a compression spring, and the upper end of the compression spring is fixed on the adjustment plug 620, and the lower end is fixed to the bottom of the adjustment cylinder 610. The deflector umbrella 660 is coaxially fixed on the connecting rod 630, and the deflector umbrella 660 is located above the adjustment cylinder 610. Regarding the liquid level height when the volume of waste liquid in the gas-liquid separator 200 reaches the target volume, it should be noted that the liquid level height when the target volume is reached is lower than the initial height of the regulating plug 620, that is, the height position of the regulating plug 620 when the compression spring is not compressed.

[0052] Understandably, the pressure on the upper end of the regulating plug 620 is always the same as the gas pressure p0 inside the gas-liquid separator 200, while the pressure p1 on the lower end of the regulating plug 620 depends on the height difference between the waste liquid surface outside the siphon shroud 500 and the lower end face of the regulating plug 620. When the volume of waste liquid inside the gas-liquid separator 200 is large, the waste liquid surface is high. At this time, the height difference h between the waste liquid surface outside the siphon shroud 500 and the lower end face of the regulating plug 620 is small. The difference between the pressure p1 on the lower end of the regulating plug 620 and the pressure p0 on the upper end of the regulating plug 620 is small. That is, the elastic element 640 is compressed less, and the connecting rod 630 pulls the support ring 440 downward a shorter distance, meaning the conical guide portion 430 maintains a small taper. Conversely, when the liquid level of the waste liquid decreases, the height difference h between the waste liquid level outside the siphon 500 and the lower end face of the regulating plug 620 increases, and the pressure p1 on the lower end of the regulating plug 620 decreases. At this time, the regulating plug 620 moves downward under the action of the pressure difference, causing the elastic element 640 to be compressed. At this time, the connecting rod 630 pulls the support ring 440 downward, which increases the taper of the conical guide part 430 to increase the resistance to the waste liquid flowing out of the outlet of the first pipe 310.

[0053] Furthermore, such as Figure 6 As shown, to connect the connecting rod 630 to the support ring 440, a support frame 650 is fixed to the outside of the connecting rod 630, and the outer side of the support frame 650 is fixed to the inner circumferential surface of the support ring 440. This makes the support ring 440, the support frame 650, and the connecting rod 630 a single unit.

[0054] It should be noted that, as Figure 6 and Figure 9As shown, a baffle umbrella 660 is provided above the regulating cylinder 610 to prevent waste liquid from being directly poured into the regulating cylinder 610 and located in the area above the regulating plug 620.

[0055] In a further embodiment, such as Figure 1 and Figure 3 As shown, heat exchanger 100 is a tubular heat exchanger 100. Specifically, the tube side of the tubular heat exchanger 100 is the first fluid channel, and the shell side of the tubular heat exchanger 100 is the second fluid channel. It should also be noted that the outlet of the second fluid channel is connected to the collection system of the preheater to collect the water vapor after the waste heat has been absorbed.

[0056] In a further embodiment, such as Figure 1 As shown, a transparent window 210 is provided on the side of the gas-liquid separator 200.

[0057] The purpose of opening a transparent window 210 is to facilitate staff to observe the working conditions inside the gas-liquid separator 200, such as changes in liquid level.

[0058] In a further embodiment, a support platform (not shown in the figure) is provided on the outside of the gas-liquid separator 200 to support the gas-liquid separator 200.

[0059] A support platform is provided to support the gas-liquid separator 200.

[0060] A process for treating waste liquid from the production of methylcyclohexanediamine, using the aforementioned treatment method, includes the following steps: S100. Add the target volume of waste liquid into the gas-liquid separator 200; S200, causing the waste liquid to circulate between the gas-liquid separator 200 and the first fluid channel, and causing the gas phase in the gas-liquid separator 200 to be transported to the second fluid channel; S300: When the concentration of waste liquid in the gas-liquid separator 200 increases to the target concentration, the waste liquid is transported to the storage container. S400, repeat S100-S300 until all the waste liquid in the current batch is sent into the gas-liquid separator 200.

[0061] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0062] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the appended claims.

Claims

1. A wastewater treatment device for methylcyclohexanediamine production, characterized in that, include: A heat exchanger having a first fluid channel and a second fluid channel that are mutually isolated but capable of exchanging heat with each other; The gas-liquid separator is located above the heat exchanger; Fluid transport assembly for transporting waste liquid into a gas-liquid separator; And for circulating the waste liquid between the first fluid channel and the gas-liquid separator, and for making the outlet direction of the waste liquid in the gas-liquid separator face upward; and for conveying the gas phase in the gas-liquid separator to the second fluid channel; and for conveying the waste liquid with the concentration increased to the target solubility to the storage container; An annular guide element, located inside the gas-liquid separator, is configured with a downwardly inclined guide surface to cause the gas phase and waste liquid to be radially dispersed and move downward along the guide surface.

2. The methylcyclohexanediamine production wastewater treatment equipment according to claim 1, characterized in that, The fluid transport assembly includes a first pipe, a second pipe, a third pipe, and a fourth pipe. The inlet of the first pipe has a first branch and a second branch. The first branch is connected to the outlet of the first fluid channel, and the second branch is connected to the main input of the waste liquid. The outlet of the first pipe is connected to a gas-liquid separator, and the outlet opening of the first pipe faces upward. The inlet of the second pipe is located inside the gas-liquid separator, and the inlet height is lower than the outlet height of the first pipe. The outlet of the second pipe is connected to the inlet of the first fluid channel. The inlet of the third pipe is connected to the top of the gas-liquid separator, and the outlet is connected to the inlet of the second fluid channel. The fourth pipe is connected between the bottom of the gas-liquid separator and the storage container, and is used to transport the waste liquid with the concentration increased to the target concentration to the storage container.

3. The methylcyclohexanediamine production wastewater treatment equipment according to claim 1, characterized in that, The annular guide includes a support cage, a circular plate, a conical guide section, and a support ring. The support cage is fixed to the upper end of the first pipe, the circular plate is fixed to the upper end of the support cage, the support ring is coaxial with the circular plate and is located below the circular plate, and the small end of the conical guide section is fixed to the circular plate and the large end is fixed to the support ring.

4. The methylcyclohexanediamine production wastewater treatment equipment according to claim 3, characterized in that, The waste liquid treatment equipment for methylcyclohexanediamine production also includes a siphon hood, which is located inside the gas-liquid separator and fixed to the outer periphery of the first pipe. The siphon hood is open at the bottom and sealed at the top; Furthermore, the lower opening height of the siphon hood is less than the upper opening height of the second pipe.

5. The methylcyclohexanediamine production wastewater treatment equipment according to claim 4, characterized in that, The tapered guide section is made of elastic material; An adjustment assembly is provided between the support ring and the siphon shroud to adjust the taper of the tapered guide section; Furthermore, the taper of the conical guide section is negatively correlated with the volume of waste liquid in the gas-liquid separator.

6. The methylcyclohexanediamine production wastewater treatment equipment according to claim 5, characterized in that, The adjustment assembly includes an adjustment cylinder, an adjustment plug, a connecting rod, and an elastic element. The adjustment cylinder is embedded in the upper part of the siphon shroud, and both ends of the adjustment cylinder are open. The adjustment plug is slidably connected coaxially inside the adjustment cylinder to divide the interior of the adjustment cylinder into upper and lower parts. The upper part of the connecting rod is fixedly connected to the support ring, and the lower part is fixedly connected coaxially to the adjustment plug. The elastic element is sleeved on the outside of the connecting rod, and both ends of the elastic element are connected to the adjustment plug and the adjustment cylinder, respectively.

7. The methylcyclohexanediamine production wastewater treatment equipment according to claim 1, characterized in that, The heat exchanger is a tubular heat exchanger.

8. The methylcyclohexanediamine production wastewater treatment equipment according to claim 1, characterized in that, A transparent window is provided on the side of the gas-liquid separator.

9. The methylcyclohexanediamine production wastewater treatment equipment according to claim 1, characterized in that, The gas-liquid separator is equipped with an external support platform to support it.

10. A process for treating waste liquid from the production of methylcyclohexanediamine, using the waste liquid treatment equipment for the production of methylcyclohexanediamine according to any one of claims 1-9, characterized in that, Includes the following steps: S100. Add the target volume of waste liquid into the gas-liquid separator; S200, causing the waste liquid to circulate between the gas-liquid separator and the first fluid channel, and causing the gas phase in the gas-liquid separator to be transported to the second fluid channel; S300: When the concentration of waste liquid in the gas-liquid separator increases to the target concentration, the waste liquid is transported to the storage container. S400, repeat S100-S300 until all the waste liquid in the current batch is sent into the gas-liquid separator.

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