Triethylene glycol dehydration tail gas treatment system

Abstract

The utility model relates to the technical field of triethylene glycol dehydration, and provides a triethylene glycol dehydration tail gas treatment system. The triethylene glycol dehydration tail gas treatment system comprises a dehydration module, a separator, a buffer tank and a combustor which are sequentially connected in a sealing manner, tail gas generated by the dehydration module is introduced into the separator to be separated into a liquid phase and residual gas, the separator is provided with an air pressure detector capable of detecting the air pressure in the separator, and the separator is communicated with the buffer tank through a first control valve; the buffer tank is connected with a gas supply pump, and the gas supply pump is configured to inject fuel gas with first set pressure into the buffer tank; the first control valve is electrically connected with the air pressure detector, and when the air pressure in the separator is larger than first set pressure, the first control valve is opened, so that the residual gas is introduced into the buffer tank and mixed with the fuel gas; the combustor is connected with the dehydration module and used for combusting the mixed gas output by the buffer tank and supplying heat to the dehydration module. Tail gas generated by the dehydration module is accumulated in the separator for self-pressurization, and the effect that no extra pressurization equipment needs to be arranged is achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of triethylene glycol dehydration, and particularly to a triethylene glycol dehydration tail gas treatment system. BACKGROUND

[0002] The triethylene glycol dehydration device is a device for absorbing saturated water in natural gas by using triethylene glycol. While the saturated water is removed, the removed water is discharged in the form of condensed tail gas. The main components of the tail gas are water vapor, gaseous aromatic hydrocarbons and a small amount of glycol. The tail gas cannot be directly discharged into the air because the gaseous aromatic hydrocarbons and the small amount of glycol in the tail gas will pollute the environment.

[0003] The existing tail gas treatment technology generally adopts a gaseous medium recompression process, that is, a booster device such as a blower, a reciprocating compressor or an ejector is added to implement secondary pressurization on the tail gas, and the pressurized tail gas is introduced into a treatment device to remove gaseous hydrocarbons and glycol. However, the addition of the device for pressurizing the tail gas in the triethylene glycol dehydration device occupies additional area of the station and increases the number of devices of the triethylene glycol dehydration device, thereby increasing the cost of treating the tail gas of the triethylene glycol dehydration device as a whole. CONTENT OF THE UTILITY MODEL

[0004] In order to solve the above technical problems or at least partially solve the above technical problems, the present application provides a triethylene glycol dehydration tail gas treatment system.

[0005] The present application provides a triethylene glycol dehydration tail gas treatment system, which comprises a dehydration module, a separator, a buffer tank and a burner which are sequentially and sealingly connected.

[0006] The tail gas generated by the dehydration module can be introduced into the separator to be separated into a liquid phase and residual gas. The separator is provided with a gas pressure detector capable of detecting the internal gas pressure of the separator and is in communication with the buffer tank through a first control valve.

[0007] The buffer tank is connected with a gas supply pump configured to inject fuel gas with a first set pressure into the buffer tank.

[0008] The first control valve is electrically connected with the gas pressure detector. When the internal gas pressure of the separator is greater than the first set pressure, the first control valve is opened to allow the residual gas to be introduced into the buffer tank and mixed with the fuel gas.

[0009] The burner is connected with the dehydration module and is used for burning the mixed gas output by the buffer tank and supplying heat to the dehydration module.

[0010] Optionally, the dehydration module comprises a purification tank, a rectifying column, a heating cylinder and a chimney.

[0011] The purification tank is used for storing triethylene glycol, and the heating cylinder is arranged in the purification tank and communicated with the burner at one end and with the chimney at the other end.

[0012] The bottom end of the rectifying column is communicated with the purification tank, and the top end of the rectifying column is communicated with the separator.

[0013] Optionally, the dehydration module further comprises an air cooler connected between the rectifying column and the separator, so that the gas discharged from the rectifying column can enter the separator through the air cooler.

[0014] Optionally, a first temperature detector is arranged upstream of the air cooler, and a second temperature detector is arranged downstream of the air cooler, the first temperature detector being capable of detecting the temperature of the gas entering the air cooler, and the second temperature detector being capable of detecting the temperature of the gas discharged from the air cooler.

[0015] Optionally, the air cooler comprises a cooling pipe communicated with the rectifying column and the separator, and a driving member arranged outside the cooling pipe, the driving member being capable of driving the cooling medium to exchange heat with the cooling pipe to reduce the temperature of the cooling pipe when activated; the second temperature detector is electrically connected with the driving member, and the driving member is activated when the temperature data detected by the second temperature detector is higher than a set temperature.

[0016] Optionally, the top end of the separator is further connected with a vent pipe, one end of the vent pipe being communicated with the separator and the other end being provided with a discharge port.

[0017] The vent pipe is provided with a second control valve electrically connected with the gas pressure detector, the second control valve being capable of being opened when the gas pressure in the separator is greater than a second set pressure, so that the gas in the separator is discharged from the separator through the discharge port.

[0018] The second set pressure is greater than the first set pressure.

[0019] Optionally, the end of the vent pipe away from the separator is provided with a flare, the flare being capable of burning the gas discharged from the discharge port.

[0020] Optionally, the separator is provided with a first liquid level detector, a first liquid discharge pipe and a third control valve.

[0021] The first liquid level detector can detect the position of the liquid in the separator, one end of the first liquid discharge pipe is communicated with the bottom end of the separator, the other end is provided with a first liquid discharge port, the third control valve is arranged on the first liquid discharge pipe and is electrically connected with the first liquid level detector, and the third control valve can be opened when the position of the liquid surface in the separator is higher than the first liquid level, so that the liquid in the separator is discharged from the separator through the first liquid discharge port under the driving of the pressure in the separator.

[0022] Optionally, the buffer tank is provided with a second liquid level detector, a second liquid discharge pipe and a fourth control valve.

[0023] The second liquid level detector can detect the position of the liquid in the buffer tank, one end of the second liquid discharge pipe is communicated with the bottom end of the buffer tank, the other end is provided with a second liquid discharge port, the fourth control valve is arranged on the second liquid discharge pipe and is electrically connected with the second liquid level detector, and the fourth control valve can be opened when the position of the liquid in the buffer tank is higher than the second liquid level, so that the liquid in the buffer tank is discharged from the buffer tank through the second liquid discharge port under the driving of the pressure in the buffer tank.

[0024] Optionally, a pressure stabilizing valve is arranged between the buffer tank and the combustor, so that the gas passing through the pressure stabilizing valve can enter the combustor at a third set pressure.

[0025] The technical scheme provided in the application has the following advantages compared with the prior art:

[0026] The triethylene glycol dehydration tail gas treatment system, the dehydration module, the separator, the buffer tank and the combustor are sequentially and sealingly connected and cooperated with each other to form a sealed pipeline; the gas supply pump provides the fuel gas with a constant pressure to the buffer tank, so that the fuel gas can continuously enter the combustor for combustion; when the first control valve is closed, the tail gas generated by the dehydration module accumulates in the separator, so that the gas pressure in the separator gradually increases; when the gas pressure in the separator is greater than the first set pressure, the first control valve is opened to enable the gas in the separator to enter the buffer tank, so that the residual gas can be fully mixed with the fuel gas in the buffer tank and then enter the combustor for full combustion; the tail gas generated by the dehydration module can accumulate in the separator to increase the pressure by itself, the pressure difference between the separator and the buffer tank during the tail gas treatment process is utilized to drive the flow of the tail gas, the setting of a pressure increasing device in the triethylene glycol dehydration tail gas treatment system is avoided, the number of components of the tail gas treatment system is reduced, the occupied area of the tail gas treatment system is reduced, the manufacturing and use costs of the tail gas treatment system are reduced, and the cost of treating the tail gas in the triethylene glycol dehydration process is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0027] The accompanying drawings, which are incorporated herein and form part of the specification, illustrate embodiments consistent with the present application and, together with the description, further serve to explain the principles of the application.

[0028] In order to more clearly illustrate the technical solutions of the embodiments of the present application or the prior art, the accompanying drawings required by the embodiments or prior art description will be briefly introduced as follows. Obviously, for those skilled in the field, other drawings can also be obtained based on these drawings without any creative effort.

[0029] Figure 1 The triethylene glycol dehydration tail gas treatment system is provided.

[0030] Wherein, 1, dehydration module; 11, purification tank; 12, rectification column; 13, heating cylinder; 14, air cooler; 141, first temperature detector; 142, second temperature detector; 15, chimney; 2, separator; 21, gas pressure detector; 22, first control valve; 23, vent pipe; 24, second control valve; 25, first liquid discharge pipe; 26, first liquid level detector; 27, third control valve; 3, buffer tank; 31, gas supply pump; 32, second liquid discharge pipe; 33, second liquid level detector; 34, fourth control valve; 35, pressure stabilizing valve; 4, burner. DETAILED DESCRIPTION

[0031] In order to more clearly illustrate the technical solutions of the embodiments of the present application or the prior art, the accompanying drawings required by the embodiments or prior art description will be briefly introduced as follows. Obviously, for those skilled in the field, other drawings can also be obtained based on these drawings without any creative effort.

[0032] In the following description, a large number of specific details are set forth in order to facilitate a thorough understanding of the present application, but the present application can also be implemented in other ways different from those described herein; obviously, the embodiments in the specification are only a part of the embodiments of the present application, not all the embodiments.

[0033] Reference Figure 1 As shown in the figure, the triethylene glycol dehydration tail gas treatment system provided by the embodiments of the present application comprises a dehydration module 1, a separator 2, a buffer tank 3 and a burner 4 which are sequentially and sealingly connected; the tail gas generated by the dehydration module 1 can be introduced into the separator 2 to be separated into liquid phase and residual gas, the separator 2 is provided with a gas pressure detector 21 capable of detecting the internal gas pressure of the separator 2, and is communicated with the buffer tank 3 through a first control valve 22; the buffer tank 3 is connected with a gas supply pump 31, and the gas supply pump 31 is configured to inject fuel gas with a first set pressure into the buffer tank 3; the first control valve 22 is electrically connected with the gas pressure detector 21, and when the internal gas pressure of the separator 2 is greater than the first set pressure, the first control valve 22 is opened to make the residual gas enter the buffer tank 3 and mix with the fuel gas; the burner 4 is connected with the dehydration module 1, and is used for burning the mixed gas output by the buffer tank 3 and supplying heat to the dehydration module 1.

[0034] Specifically, the dehydration module 1, the separator 2, the buffer tank 3 and the combustor 4 can be connected with each other through pipes, and the pipes and the dehydration module 1, the separator 2, the buffer tank 3 and the combustor 4 can be connected with each other through flanges, and the end of the pipe is provided with a sealing gasket, so that the sealing gasket can be in sealing abutment with the dehydration module 1, the separator 2, the buffer tank 3 and the combustor 4, so as to form a closed pipeline system by sequentially connecting the dehydration module 1, the separator 2, the buffer tank 3 and the combustor 4.

[0035] The dehydration module 1 has a tank body for containing triethylene glycol, the triethylene glycol is stored in the tank body, the tank body is provided with a tail gas outlet, the tail gas outlet is communicated with the inside of the separator, and the triethylene glycol in the tank body can be heated, so that the water in the triethylene glycol is evaporated into water vapor, part of the triethylene glycol is evaporated into triethylene glycol vapor, and gaseous aromatic hydrocarbon is generated, and the water vapor, the triethylene glycol vapor and the gaseous aromatic hydrocarbon are mixed to form tail gas.

[0036] The separator 2 can be a vertical pressure vessel, and the separator 2 is provided with a wire mesh mist catcher for capturing small liquid in residual tail gas; the tail gas is separated into liquid droplets and residual gas after passing through the separator 2. The top of the separator 2 is provided with a gas outlet, and the gas outlet is communicated with the buffer tank 3 through the tank body, so that the residual gas can be introduced into the buffer tank 3 through the pipe body.

[0037] The gas pressure detector 21 can be a pressure transmitter or a gas pressure gauge, and the gas pressure detector 21 can be installed in the gas phase space at the top of the separator 2, or the detection end of the gas pressure detector 21 can enter the inside of the separator 2 and be in the gas phase space at the top of the separator 2, as long as the gas pressure detector 21 can detect the pressure of the gas in the separator 2.

[0038] The first control valve 22 can be a pneumatic regulating valve or an electric regulating valve, and the first control valve 22 is installed on the pipe between the separator 2 and the buffer tank 3. When the first control valve 22 is closed, the separator 2 and the buffer tank 3 are isolated from each other, and the tail gas in the dehydration module 1 continuously enters the separator 2, so that the pressure of the gas in the separator 2 continuously increases. When the pressure of the gas in the separator 2 increases to be greater than a first set pressure, the first control valve 22 is opened, so that the gas in the separator 2 can enter the buffer tank 3.

[0039] The gas supply pump 31 introduces fuel gas with a constant pressure into the buffer tank 3, and the fuel gas is natural gas. The gas supply pump 31 introduces the fuel gas into the buffer tank 3 at a first set pressure. When the first control valve 22 is closed, the fuel gas in the buffer tank 3 is kept at the first set pressure. When the increase of the pressure of the gas in the separator 2 is greater than the first set pressure, the first control valve 22 is opened, so that the gas in the separator 2 can enter the buffer tank 3, and the residual gas and the fuel gas are mixed.

[0040] The combustor 4 can selectively include a combustion chamber and a U-shaped heating pipe, one end of the U-shaped heating pipe being communicated with the combustion chamber and the other end being connected with a chimney. The U-shaped heating pipe is immersed in the dehydration module 1. When the first control valve 22 is closed, the fuel gas in the buffer tank 3 enters the combustion chamber to be combusted. The high-temperature flue gas generated by the combustion heats the triethylene glycol in the dehydration module 1 through the U-shaped heating pipe. When the first control valve 22 is opened, the residual gas is mixed with the fuel gas in the buffer tank 3 and then enters the combustion chamber to be combusted, so that the combustion gas dilutes the residual gas, thereby avoiding pollution of the atmosphere caused by incomplete combustion of the residual gas.

[0041] The triethylene glycol dehydration tail gas treatment system provided by the embodiment of the present application is sealed and connected in sequence and cooperates with each other to form a sealed pipeline. The gas supply pump 31 provides the buffer tank 3 with fuel gas of constant pressure, so that the fuel gas can continuously enter the combustor 4 to be combusted. When the first control valve 22 is closed, the tail gas generated by the dehydration module 1 accumulates in the separator 2, so that the gas pressure in the separator 2 gradually increases. When the gas pressure in the separator 2 is greater than the first set pressure, the first control valve 22 is opened to enable the gas in the separator 2 to enter the buffer tank 3, so that the residual gas can be mixed with the fuel gas in the buffer tank 3 and then enter the combustor 4 to be fully combusted. The tail gas generated by the dehydration module 1 accumulates in the separator 2 to increase the pressure by itself. The pressure difference between the separator 2 and the buffer tank 3 during the tail gas treatment process is used to drive the flow of the tail gas, thereby avoiding the need to set a pressure increasing device in the triethylene glycol dehydration tail gas treatment system, reducing the number of components of the tail gas treatment system, reducing the occupied area of the tail gas treatment system, reducing the manufacturing and use costs of the tail gas treatment system, and reducing the cost of treating the tail gas in the triethylene glycol dehydration process.

[0042] In actual use, the triethylene glycol is stored in the dehydration module 1. The gas supply pump 31 supplies the buffer tank 3 with fuel gas, which then enters the combustor 4 to be combusted. The combustor 4 heats the triethylene glycol in the dehydration module 1, so that the water in the triethylene glycol evaporates into water vapor, part of the triethylene glycol evaporates into triethylene glycol vapor, and gaseous aromatic hydrocarbons are generated. The water vapor, triethylene glycol vapor and gaseous aromatic hydrocarbons are mixed to form tail gas. The tail gas enters the separator 2 to be separated into liquid phase and residual gas. When the gas pressure in the separator 2 is less than the first set pressure, the first control valve 22 is closed, and the tail gas continuously enters the separator 2, so that the gas pressure in the separator 2 continuously increases. When the gas pressure in the separator 2 is greater than the first set pressure, the first control valve 22 is opened, and the residual gas enters the buffer tank 3 to be mixed with the fuel gas and then enters the combustor 4 to be combusted. When the gas in the separator 2 enters the buffer tank 3, the gas pressure in the separator 2 gradually decreases. When the gas pressure in the separator 2 decreases to less than the first set pressure, the first control valve 22 is closed.

[0043] Reference Figure 1As shown, in some embodiments, the dehydration module 1 comprises a purification tank 11, a rectifying column 12, a heating cylinder 13 and a chimney 15; the purification tank 11 is used for storing triethylene glycol, the heating cylinder 13 is arranged in the purification tank 11, one end of the heating cylinder 13 is communicated with the burner 4, and the other end of the heating cylinder 13 is connected with the chimney 15; the bottom end of the rectifying column 12 is communicated with the purification tank 11, and the top end of the rectifying column 12 is communicated with the separator 2.

[0044] In this way, the heating cylinder 13 can transfer the heat of the flue gas generated by the burner 4 to the purification tank 11, the rectifying column 12 can preliminarily separate the gas generated by heating the triethylene glycol, and the high-temperature flue gas generated by the burner 4 can be discharged through the chimney 15 after heat exchange by the heating cylinder 13.

[0045] Specifically, the purification tank 11 can be selected as a hollow pressure container, the inside of the purification tank 11 can store triethylene glycol, the side wall of the purification tank 11 is provided with a first opening, the top of the purification tank 11 is provided with a second opening, the heating cylinder 13 is immersed in the inside of the purification tank 11 through the first opening, so that the heating cylinder 13 can heat the triethylene glycol in the purification tank 11; the bottom end of the rectifying column 12 is connected with the purification tank 11 through the second opening, so that the gas generated by heating the triethylene glycol can enter the rectifying column 12.

[0046] The rectifying column 12 described above is arranged in a vertical direction and installed at the top of the purification tank 11, the rectifying column 12 can realize multiple contact and mass transfer of gas-liquid two phases, so as to separate and purify different boiling point components in the mixture. The triethylene glycol is heated to generate gas at the bottom side of the rectifying column 12, the gas enters the rectifying column 12 and condenses backflow in the process of rising, and the above process is repeated, so that the gas generated by heating the triethylene glycol is separated in the rectifying column 12 and exhaust gas is discharged from the rectifying column 12.

[0047] The heating cylinder 13 described above can be selected as a U-shaped tubular cylinder, one end of the cylinder is connected with the burner 4, and the other end of the cylinder is connected with the chimney 15, the U-shaped cylinder is immersed in the purification tank 11, and the two ends of the U-shaped cylinder are outside the purification tank 11 to be connected with the burner 4 and the chimney 15 respectively; the high-temperature flue gas generated by combustion in the burner 4 enters the heating cylinder 13, so that the heating cylinder 13 exchanges heat with the triethylene glycol in the purification tank 11, thereby indirectly heating the triethylene glycol in the purification tank 11 by the high-temperature flue gas generated by the burner 4.

[0048] The chimney 15 described above can be selected as a vertical pipe, the part of the heating cylinder 13 outside the purification tank 11 is provided with a mounting hole, and the bottom end of the chimney 15 can be connected with the mounting hole of the heating cylinder 13 in a sealed manner through a corrugated expansion joint or a flange.

[0049] The top of the chimney 15 is provided with an opening, so that the high-temperature gas in the heating cylinder 13 can be discharged through the opening; the top of the chimney 15 can be provided with a conical rainproof cap. The inside of the chimney 15 can be optionally provided with three groups of spiral guide plates for eliminating smoke vortex. The outer wall of the chimney 15 is wrapped with a heat preservation layer to reduce heat loss.

[0050] Referring to Figure 1 As shown in the figure, in some embodiments, the dehydration module 1 further comprises an air cooler 14 connected between the rectifying column 12 and the separator 2, so that the gas discharged from the rectifying column 12 can enter the separator 2 through the air cooler 14.

[0051] In this way, the air cooler 14 can cool the tail gas entering the separator 2, so that the water vapor in the tail gas is condensed to preliminarily separate the tail gas, thereby improving the separation efficiency of the tail gas in the separator 2.

[0052] The air cooler 14 described above can optionally comprise a cooling pipe and a fan, a plurality of finned tubes are arranged on the outer side of the cooling pipe, a fan is arranged on the outer side of the cooler, the inlet of the cooling pipe is sealingly connected to the top gas phase outlet of the rectifying column 12, and the outlet is sealingly connected to the top of the separator 2. When the fan is started, it can blow air through the fins on the outer side of the cooling pipe, so that the air and the fins exchange heat, thereby reducing the temperature of the gas in the cooling pipe.

[0053] Referring to Figure 1 As shown in the figure, in some embodiments, a first temperature detector 141 is arranged upstream of the air cooler 14, and a second temperature detector 142 is arranged downstream of the air cooler 14. The first temperature detector 141 can detect the temperature of the gas entering the air cooler 14, and the second temperature detector 142 can detect the temperature of the gas discharged from the air cooler 14.

[0054] In this way, by comparing the detection data of the first temperature detector 141 and the second temperature detector 142, the cooling efficiency of the air cooler 14 can be determined.

[0055] Specifically, the air cooler 14 is sealingly connected to the rectifying column 12 and the separator 2 through a pipe body, the first temperature detector 141 is installed at the center line position of the pipe body at the inlet of the air cooler 14, and the second temperature detector 142 is installed on the pipe body downstream of the air cooler 14.

[0056] Referring to Figure 1 As shown in the figure, in some embodiments, the air cooler 14 comprises a cooling pipe and a driving member, the cooling pipe is in communication with the rectifying column 12 and the separator 2, the driving member is arranged on the outer side of the cooling pipe, and the driving member is started to drive the cooling medium to exchange heat with the cooling pipe to reduce the temperature of the cooling pipe; the second temperature detector 142 is electrically connected with the driving member, and the driving member is started when the temperature data detected by the second temperature detector 142 is higher than the set temperature.

[0057] In this way, the second temperature detector 142 is used to realize automatic control of the air cooler 14, and the temperature of the tail gas entering the separator 2 can be precisely controlled.

[0058] Specifically, the cooling pipe is hollow inside, and the gas can flow in the cooling pipe. The outer side of the cooling pipe can be provided with multiple fins. The driving member can be a axial flow fan, which is arranged towards the cooling pipe. The axial flow fan drives the air to flow through the surface of the cooling pipe, so that the air exchanges heat with the cooling pipe to reduce the temperature of the gas inside the cooling pipe.

[0059] Of course, the cooling pipe can also be hollow inside, and the outer wall of the cooling pipe is surrounded by a heat dissipation pipe. The driving member is a water pump, which is connected with the heat dissipation pipe. The water pump can continuously supply water to the heat dissipation pipe, so that the water continuously flows through the heat dissipation pipe to exchange heat with the cooling pipe. The water acts as a cooling medium to reduce the temperature of the cooling pipe.

[0060] The driving member has a chip or a computer as a controller, which can control the start and stop of the driving member. The second temperature detector 142 is electrically connected with the controller. When the second temperature detector 142 detects that the temperature of the gas discharged from the cooling pipe is higher than the set temperature, the driving member is started to reduce the temperature of the gas in the cooling pipe.

[0061] Referring to Figure 1 In some embodiments, the top end of the separator 2 is also connected with a vent pipe 23. One end of the vent pipe 23 is in communication with the separator 2, and the other end is provided with a discharge port. The vent pipe 23 is provided with a second control valve 24 electrically connected with the gas pressure detector 21. The second control valve 24 can be opened when the gas pressure in the separator 2 is greater than the second set pressure, so that the gas in the separator 2 is discharged from the separator 2 through the discharge port. The second set pressure is greater than the first set pressure.

[0062] In this way, when the pressure in the separator 2 is too high, the second control valve 24 can be opened to quickly discharge the gas in the separator 2, so that the gas pressure in the separator 2 is quickly reduced to avoid damage to the separator 2.

[0063] Specifically, the vent pipe 23 can be a hollow pipe body. One end of the vent pipe 23 is sealingly connected with the gas phase outlet at the top of the separator 2, and the other end is in communication with the vent flare. The second control valve 24 can be an electric ball valve or a pneumatic valve. The gas pressure detector 21 is electrically connected with the second control valve 24, so that the gas pressure detector 21 can control the second control valve 24 to be opened and then closed.

[0064] When the second control valve 24 is opened, the separator 2 is communicated with the flare through the vent pipe 23, so that the gas in the separator 2 can be discharged out of the separator 2 through the vent pipe 23. When the second control valve 24 is closed, the vent pipe 23 is blocked, so that the gas in the separator 2 cannot be discharged out of the separator 2 through the vent pipe 23. The first set pressure can be selected as 30 kPa, and the second set pressure can be selected as 50 kPa.

[0065] When the gas pressure detector 21 detects that the obtained gas pressure data is less than the first set pressure, the first control valve 22 and the second control valve 24 are both closed, and the gas pressure in the separator 2 gradually increases. When the gas pressure data is between the second set pressure and the first set pressure, the first control valve 22 is opened, and the second control valve 24 is closed, so that the gas in the separator 2 enters the buffer tank 3, and the gas pressure in the separator 2 is reduced. When the tail gas entering the separator 2 is too much, so that the discharge amount of the gas in the separator 2 is less than the entering amount, the gas pressure in the separator 2 continues to increase, that is, the gas pressure data is greater than the second set pressure. At this time, in order to protect the separator 2, the first control valve 22 and the second control valve 24 are both opened, so that the gas in the separator 2 can also be discharged out of the separator 2 through the vent pipe 23.

[0066] Referring to Figure 1 In some embodiments, the end of the vent pipe 23 away from the separator 2 is provided with a flare, and the flare can burn the gas discharged from the discharge port.

[0067] In this way, the flare burns the gas discharged from the discharge port, consumes the gaseous hydrocarbon in the gas discharged from the vent pipe 23, and reduces the pollution to the environment when the separator 2 is urgently depressurized.

[0068] Specifically, a flare head is arranged at the opening of the vent pipe 23, and the flare head can be electrically connected with the gas pressure detector 21. When the gas pressure data is greater than the second set pressure, the flare head is ignited to burn the gas discharged from the discharge port, so as to consume the gaseous hydrocarbon in the gas discharged from the vent pipe 23 and reduce the pollution to the environment.

[0069] Referring to Figure 1 In some embodiments, the separator 2 is provided with a first liquid level detector 26, a first liquid discharge pipe 25 and a third control valve 27. The first liquid level detector 26 can detect the position of the liquid in the separator 2. One end of the first liquid discharge pipe 25 is communicated with the bottom end of the separator 2, and the other end is provided with a first liquid discharge port. The third control valve 27 is arranged on the first liquid discharge pipe 25 and is electrically connected with the first liquid level detector 26. When the position of the liquid surface in the separator 2 is higher than the first liquid level, the third control valve 27 is opened, so that the liquid in the separator 2 is discharged out of the separator 2 through the first liquid discharge port under the driving of the pressure in the separator 2.

[0070] In this way, through the cooperation of the first liquid level detector 26 and the third control valve 27, the amount of liquid remaining in the separator 2 can be monitored in real time, so that the third control valve 27 is opened when the amount of liquid remaining in the separator 2 is too much, and the liquid in the separator 2 is discharged in time; avoid the effect of the separator 2 on the separation of the tail gas. The tail gas continues to flow into the separator 2, so that the pressure of the gas in the separator 2 gradually increases, so that the pressure of the gas in the separator 2 is greater than the external pressure; when the third control valve 27 is opened, the liquid in the separator 2 will be automatically discharged from the separator 2 under the driving of the gas pressure in the separator 2, without the need to install a water pump or other driving device on the separator 2, thereby reducing the components required by the triethylene glycol dehydration tail gas treatment system.

[0071] Specifically, the first liquid level detector 26 can be selected as a magnetic flap liquid level meter, and of course can also be selected as a double-flange differential pressure liquid level meter. The first liquid discharge pipe 25 is arranged at the bottom end of the separator 2, and the third control valve 27 can be selected as a pneumatic valve or an electric valve; when the third control valve 27 is closed, the first liquid discharge pipe 25 is closed, and the liquid and gas in the separator 2 cannot pass through the first liquid discharge pipe 25; when the third control valve 27 is opened, the liquid in the separator 2 is pushed by the gas pressure in the separator 2 and discharged from the separator 2 through the first liquid discharge pipe 25. The first liquid discharge pipe 25 can be selected to communicate with a sewage pool, so that the liquid in the separator 2 is discharged into the sewage pool through the first liquid discharge pipe 25.

[0072] The separated liquid phase in the separator 2 accumulates at the bottom of the separator 2, and the liquid level in the separator 2 can be selected as the distance between the liquid surface of the liquid in the separator 2 and the end of the first liquid discharge pipe 25 in the vertical direction. The first liquid level can be selected according to the size of the internal space of the separator 2 and the height of the separator 2; when the liquid surface of the liquid in the separator 2 is higher than the first liquid level, it indicates that the liquid in the separator 2 is stored too much, and the liquid in the separator 2 needs to be discharged; when the liquid surface of the liquid in the separator 2 is lower than the first liquid level, the third control valve 27 is closed, so that the gas can accumulate in the separator 2 to increase the gas pressure in the separator 2.

[0073] Referring to Figure 1 In some embodiments, the buffer tank 3 is provided with a second liquid level detector 33, a second liquid discharge pipe 32 and a fourth control valve 34; the second liquid level detector 33 can detect the position of the liquid in the buffer tank 3, one end of the second liquid discharge pipe 32 communicates with the bottom end of the buffer tank 3, and the other end is provided with a second liquid discharge port; the fourth control valve 34 is arranged on the second liquid discharge pipe 32 and is electrically connected with the second liquid level detector 33, and the fourth control valve 34 can be opened when the position of the liquid in the buffer tank 3 is higher than the second liquid level, so that the liquid in the buffer tank 3 is discharged from the buffer tank 3 under the driving of the pressure in the buffer tank 3 through the second liquid discharge port.

[0074] In this way, fuel gas continuously flows into the buffer tank 3, so that the pressure of the gas in the buffer tank 3 is greater than the external pressure. When the fourth control valve 34 is opened, the liquid in the buffer tank 3 can be automatically discharged from the buffer tank 3 under the driving of the gas pressure in the buffer tank 3, without the need to install a water pump or other driving device on the buffer tank 3, thereby reducing the components required by the triethylene glycol dehydrated tail gas treatment system.

[0075] Specifically, the second liquid level detector 33 can be selected as a magnetic flap liquid level meter, and of course can also be selected as a double-flange differential pressure liquid level meter. The second liquid discharge pipe 32 is arranged at the bottom end of the buffer tank 3, and the fourth control valve 34 can be selected as a pneumatic valve or an electric valve; when the fourth control valve 34 is closed, the second liquid discharge pipe 32 is closed, and the liquid and gas in the buffer tank 3 cannot pass through the second liquid discharge pipe 32; when the fourth control valve 34 is opened, the liquid in the buffer tank 3 is pushed by the gas pressure in the buffer tank 3 and discharged from the buffer tank 3 through the second liquid discharge pipe 32. The second liquid discharge pipe 32 can be selected to communicate with a sewage pool, so that the liquid in the buffer tank 3 is discharged into the sewage pool through the second liquid discharge pipe 32.

[0076] The gas flowing into the buffer tank 3 from the separator 2 described above inevitably carries water vapor, and the water vapor in the buffer tank 3 will condense and accumulate at the bottom of the buffer tank 3. The liquid level in the buffer tank 3 can be selected as the distance between the liquid surface of the liquid in the buffer tank 3 and the end of the second liquid discharge pipe 32 in the vertical direction, and the second liquid level can be selected according to the size of the internal space of the buffer tank 3 and the height of the buffer tank 3; when the liquid surface of the liquid in the buffer tank 3 is higher than the second liquid level, it indicates that the liquid in the buffer tank 3 is stored too much, and the liquid in the buffer tank 3 needs to be discharged; when the liquid surface of the liquid in the buffer tank 3 is lower than the second liquid level, the third control valve 27 is closed, so that the gas can accumulate in the buffer tank 3 to increase the gas pressure in the buffer tank 3.

[0077] Referring to Figure 1 In some embodiments, a pressure stabilizing valve 35 is arranged between the buffer tank 3 and the burner 4, so that the gas passing through the pressure stabilizing valve 35 can flow into the burner 4 at a third set pressure.

[0078] In this way, the pressure stabilizing valve 35 can stabilize the pressure of the gas flowing into the burner 4, so that the gas in the burner 4 can be fully combusted.

[0079] Specifically, the pressure stabilizing valve 35 can be selected as a diaphragm type pressure stabilizing valve, a diaphragm is arranged inside the valve body of the pressure stabilizing valve 35 as a pressure sensing element, and the degree of opening and closing of the valve is controlled by the deformation of the diaphragm to adjust the pressure of the gas passing through the pressure stabilizing valve 35. The third set pressure can be selected to be equal to the first set pressure, and of course can also be selected to be less than the first set pressure.

[0080] When the first control valve 22 is opened, the gas in the separator 2 enters the buffer tank 3, so that the gas pressure in the buffer tank 3 is greater than the first set pressure. At this time, the gas entering the burner 4 will increase the gas pressure in the burner 4, which may cause the gas in the burner 4 to burn insufficiently or the length of the flame in the burner 4 to fluctuate, thereby affecting the combustion effect. The pressure stabilizing valve 35 is arranged between the buffer tank 3 and the burner 4, so that the gas flowing out of the buffer tank 3 is stabilized at the third set pressure through the pressure stabilizing valve 35, and the pressure of the gas entering the burner 4 is maintained at the third set pressure.

[0081] The triethylene glycol dehydration tail gas treatment system provided by the embodiment of the present application is used as follows: The triethylene glycol is stored in the purification tank 11, the fuel gas is supplied to the buffer tank 3 by the gas pump 31, and then the fuel gas is burned in the burner 4. The high-temperature flue gas in the burner 4 first enters the heating cylinder 13 to heat the triethylene glycol in the purification tank 11, and then is discharged through the chimney 15.

[0082] The gas of the triethylene glycol in the purification tank 11 after heating is passed through the rectifying column 12 and then the air cooler 14. The gas passing through the air cooler 14 enters the separator 2 as tail gas. The first temperature detector 141 and the second temperature detector 142 jointly monitor the cooling efficiency of the air cooler 14.

[0083] When the liquid level of the condensed water is higher than the first liquid level, the third control valve 27 is opened, so that the condensed water is discharged from the separator 2 through the first liquid discharge pipe 25. When the liquid level of the condensed water is lower than the first liquid level, the third control valve 27 is closed, so that the separator 2 is in a sealed state.

[0084] When the gas pressure in the separator 2 is less than the first set pressure, the first control valve 22 is closed, and the tail gas continuously enters the separator 2, so that the gas pressure in the separator 2 continuously increases. When the gas pressure in the separator 2 is greater than the first set pressure, the first control valve 22 is opened, and the residual gas enters the buffer tank 3 to mix with the fuel gas. The gas in the buffer tank 3 is burned in the burner 4 after being stabilized at the third set pressure through the pressure stabilizing valve 35.

[0085] When the gas in the separator 2 enters the buffer tank 3, the gas pressure in the separator 2 gradually decreases. When the gas pressure in the separator 2 decreases to less than the first set pressure, the first control valve 22 is closed.

[0086] When the liquid in the buffer tank 3 accumulates and the liquid level is higher than the second liquid level, the fourth control valve 34 is opened, so that the liquid in the buffer tank 3 is discharged from the buffer tank 3 through the second liquid discharge pipe 32. When the liquid level of the liquid in the buffer tank 3 is lower than the second liquid level, the fourth control valve 34 is closed to block the second liquid discharge pipe 32.

[0087] It has to be noted that, in the present document, relational terms are intended only to convey a possible relationship between elements or

[0088] The above description is merely that of the specific embodiments of the application and as such is not to be taken in a limiting sense. Various modifications and co nti n uations will be evident to those skilled in the art that do not depart from the spirit and scope of the application as defined by the appended claims. The specific embodiments presented, therefore, are not to be considered in a limiting sense, but are presented for purposes of illustration only, and numerous other embodiments are contemplated.

Claims

1. A triethylene glycol dehydrated tail gas treatment system characterized by, The dehydration module (1), the separator (2), the buffer tank (3) and the combustor (4) are sequentially connected by sealing; The tail gas generated by the dehydration module (1) can be introduced into the separator (2) to be separated into a liquid phase and residual gas, the separator (2) is provided with a gas pressure detector (21) capable of detecting the internal gas pressure of the separator (2), and is communicated with the buffer tank (3) through a first control valve (22); The buffer tank (3) is connected with a gas supply pump (31), and the gas supply pump (31) is configured to inject fuel gas with a first set pressure into the buffer tank (3); The first control valve (22) is electrically connected with the gas pressure detector (21), when the gas pressure in the separator (2) is greater than the first set pressure, the first control valve (22) is opened, so that the residual gas is introduced into the buffer tank (3) and mixed with the fuel gas; The combustor (4) is connected with the dehydration module (1) and is used for burning the mixed gas output by the buffer tank (3) and supplying heat to the dehydration module (1).

2. The triethylene glycol dehydration tail gas treatment system of claim 1, wherein, The dehydration module (1) comprises a purification tank (11), a rectifying column (12), a heating cylinder (13) and a chimney (15); The purification tank (11) is used for storing triethylene glycol, the heating cylinder (13) is arranged in the purification tank (11), one end of the heating cylinder (13) is communicated with the combustor (4), and the other end of the heating cylinder (13) is connected with the chimney (15); The bottom end of the rectifying column (12) is communicated with the purification tank (11), and the top end of the rectifying column (12) is communicated with the separator (2).

3. The triethylene glycol dehydration tail gas treatment system of claim 2, wherein, The dehydration module (1) further comprises an air cooler (14), the air cooler (14) is connected between the rectifying column (12) and the separator (2), so that the gas discharged from the rectifying column (12) can enter the separator (2) through the air cooler (14).

4. The triethylene glycol dehydration tail gas treatment system of claim 3, wherein, A first temperature detector (141) is arranged on the upstream side of the air cooler (14), and a second temperature detector (142) is arranged on the downstream side of the air cooler (14), the first temperature detector (141) can detect the temperature of the gas entering the air cooler (14), and the second temperature detector (142) can detect the temperature of the gas discharged from the air cooler (14).

5. The triethylene glycol dehydration tail gas treatment system of claim 4, wherein, The air cooler (14) comprises a cooling pipe and a driving member, the cooling pipe is communicated with the rectifying column (12) and the separator (2), the driving member is arranged on the outer side of the cooling pipe, and the driving member can drive the cooling medium to exchange heat with the cooling pipe to reduce the temperature of the cooling pipe when the driving member is started; the second temperature detector (142) is electrically connected with the driving member, and the driving member is started when the temperature data detected by the second temperature detector (142) is higher than a set temperature.

6. The triethylene glycol dehydration tail gas treatment system of claim 1, wherein, The top end of the separator (2) is further connected with a venting pipe (23), one end of the venting pipe (23) is communicated with the separator (2), and the other end of the venting pipe (23) is provided with a discharge port; The vent pipe (23) is provided with a second control valve (24) electrically connected with the air pressure detector (21), and the second control valve (24) is opened when the air pressure in the separator (2) is greater than a second set pressure, so that the gas in the separator (2) is discharged from the separator (2) through the discharge port. The second set pressure is greater than the first set pressure.

7. The triethylene glycol dehydration tail gas treatment system of claim 6, wherein, The end of the vent pipe (23) away from the separator (2) is provided with a flare, and the flare can burn the gas discharged from the discharge port.

8. The triethylene glycol dehydration tail gas treatment system of claim 1, wherein, The separator (2) is provided with a first liquid level detector (26), a first liquid discharge pipe (25) and a third control valve (27). The first liquid level detector (26) can detect the position of the liquid in the separator (2), one end of the first liquid discharge pipe (25) is in communication with the bottom end of the separator (2), the other end is provided with a first liquid discharge port, and the third control valve (27) is arranged on the first liquid discharge pipe (25) and electrically connected with the first liquid level detector (26). The third control valve (27) is opened when the position of the liquid surface in the separator (2) is higher than a first liquid level, so that the liquid in the separator (2) is discharged from the separator (2) through the first liquid discharge port under the driving of the pressure in the separator (2).

9. The triethylene glycol dehydration tail gas treatment system of claim 1, wherein, The buffer tank (3) is provided with a second liquid level detector (33), a second liquid discharge pipe (32) and a fourth control valve (34). The second liquid level detector (33) can detect the position of the liquid in the buffer tank (3), one end of the second liquid discharge pipe (32) is in communication with the bottom end of the buffer tank (3), the other end is provided with a second liquid discharge port, and the fourth control valve (34) is arranged on the second liquid discharge pipe (32) and electrically connected with the second liquid level detector (33). The fourth control valve (34) is opened when the position of the liquid in the buffer tank (3) is higher than a second liquid level, so that the liquid in the buffer tank (3) is discharged from the buffer tank (3) through the second liquid discharge port under the driving of the pressure in the buffer tank (3).

10. The triethylene glycol dehydration tail gas treatment system of claim 1, wherein, The buffer tank (3) and the burner (4) are provided with a pressure stabilizing valve (35), so that the gas passing through the pressure stabilizing valve (35) can enter the burner (4) at a third set pressure.

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