A triethylene glycol dehydration device for unattended station

Abstract

The utility model relates to oil and gas field ground engineering technical field discloses a triethylene glycol dehydration device for unattended station, include: dehydration system is used for carrying out dehydration to natural gas, triethylene glycol regeneration system is used for triethylene glycol's regeneration circulation, combustion system is used for providing high temperature condition, waste gas recycling system, the utility model passes through the treatment recovery to waste gas, reduces the open fire equipment, reduces the engineering investment simultaneously, both reduced the energy consumption that waste gas burning emission needed to consume, effectively eliminated the pollution of surrounding environment to the regeneration waste gas again, utilize fuel gas and compressed air to inject waste gas, adapt to the working condition of stripping gas quantity change, guarantee triethylene glycol regeneration's operating pressure for the micro positive pressure working condition under recycling waste gas, guarantee the quality of lean triethylene glycol and the smooth operation of regeneration system, can remote monitoring combustor working condition, realize the remote start function and combustion state remote monitoring function of combustor, need not personnel on duty.

Description

Technical Field

[0001] This utility model relates to the field of oil and gas field surface engineering technology, specifically, it is a triethylene glycol dehydration device for unmanned stations. Background Technology

[0002] In recent years, with the rapid development of the natural gas industry, China has also successively carried out research on digital and intelligent unmanned technologies. Standardized design, integrated devices, factory prefabrication, modular construction, intelligent control technology, safety operation management, and countermeasures for unmanned stations have seen some research and development. Currently, most triethylene glycol (TED) dehydration stations using fire-tube reboilers are still mainly operated manually, requiring long-term on-site personnel. One of the main reasons why TED dehydration stations have not achieved unmanned operation is that the TED reboiler and tail gas burner in these units use natural gas as fuel. These burners are open-flame devices, posing a risk of explosion due to gas / TED leaks and uncontrolled flames leading to equipment burnout. Since both the media (gas and TED) are flammable, and the burner is directly connected to the dehydration system, the risk is highly cascading.

[0003] Triethylene glycol regeneration typically employs atmospheric pressure regeneration at a temperature of approximately 204°C. Direct emission of the regeneration waste gas produces a strong odor. Currently, most methods involve burning the waste gas in an incinerator before direct release into the atmosphere. Incinerating the waste gas not only increases equipment investment but also wastes fuel due to the need to use co-firing natural gas, increasing carbon emissions and plant operating costs. Utility Model Content

[0004] The purpose of this invention is to provide a triethylene glycol dehydration device for unmanned stations, which solves the problems of high waste gas treatment costs and the need for personnel to be on duty in existing natural gas treatment methods.

[0005] This utility model is achieved through the following technical solution: a triethylene glycol dehydration device for an unattended station, comprising:

[0006] A dehydration system is used to dehydrate natural gas.

[0007] A triethylene glycol regeneration system, connected to the dehydration system, is used for the regeneration and circulation of triethylene glycol; the triethylene glycol regeneration system includes a fire-tube reboiler.

[0008] A combustion system, installed on the fire-tube reboiler, is used to provide high-temperature conditions; the combustion system includes an exhaust gas burner;

[0009] The waste gas recovery and utilization system is used to recover and treat the waste gas generated by the triethylene glycol regeneration system, and supply the treated waste gas to the combustion system for combustion.

[0010] The exhaust gas burner includes a feeding section and a combustion section. The feeding section is connected to the combustion section. The feeding section includes a feeding pipe and a gas supply pipe. The feeding pipe and the gas supply pipe are coaxially arranged. The gas supply pipe is located outside the feeding pipe. One end of the feeding pipe is provided with a compressed air interface and a fuel gas interface, and the other end is provided with a combined nozzle. The gas supply pipe is provided with an exhaust gas interface. The compressed air interface is connected to a compressed air pipeline, the fuel gas interface is connected to a fuel gas pipeline, and the exhaust gas interface is connected to the exhaust gas recovery and utilization system.

[0011] To better realize this utility model, the combustion section further includes an intake section, a mixing section, a diffusion section, and a flame stabilizer connected in sequence. The intake section is used to receive fuel from the feed section and burn it at the flame stabilizer. The end of the intake section near the feed section is larger than the diameter of the air supply pipe and there is a gap.

[0012] To better realize this utility model, the pipe diameter at the end of the air intake section connected to the mixing section is smaller than the pipe diameter at the end of the air intake section connected to the feed section, and the pipe diameter transitions uniformly.

[0013] To better realize this utility model, a primary air regulating disc is further provided on the air supply pipe along the axial direction to control the air intake cross-sectional area of ​​the intake section.

[0014] To better realize this utility model, the compressed air pipeline is further provided with a branch, one of which is connected to the compressed air interface and is equipped with a compressed air ejector control valve, and the other is connected to the fire tube reboiler and is equipped with a compressed air flow meter.

[0015] To better realize this utility model, the fire-tube reboiler is further equipped with an online tail gas analyzer and an online methane analyzer.

[0016] To better realize this utility model, the waste gas recovery and utilization system further includes a waste gas air cooler, a waste gas liquid separator, and a frequency conversion control circuit for the waste gas air cooler. One end of the waste gas air cooler is connected to the triethylene glycol regeneration system, and the other end is connected to the waste gas liquid separator. The waste gas liquid separator is connected to the waste gas interface. The frequency conversion control circuit for the waste gas air cooler is used to control the power of the waste gas air cooler.

[0017] To better realize this utility model, the dehydration system further includes a raw gas filter separator, a triethylene glycol absorption tower, and a dry gas / lean liquid heat exchanger. The triethylene glycol absorption tower is connected to the raw gas filter separator and the dry gas / lean liquid heat exchanger respectively. The output end of the dry gas / lean liquid heat exchanger is provided with a product gas pressure regulating valve.

[0018] To better realize this utility model, the triethylene glycol regeneration system further includes a flash tank, a triethylene glycol solution filter, a triethylene glycol circulation pump, a lean / rich liquid heat exchanger, a rich liquid heat exchange coil, a rich liquid distillation column, a lean liquid distillation column, and a lean liquid buffer tank. The triethylene glycol absorption tower, rich liquid heat exchange coil, flash tank, triethylene glycol solution filter, lean / rich liquid heat exchanger, lean liquid buffer tank, rich liquid distillation column, fire-tube reboiler, lean liquid distillation column, lean liquid buffer tank, lean / rich liquid heat exchanger, triethylene glycol circulation pump, dry gas / lean liquid heat exchanger, and triethylene glycol absorption tower are connected in sequence to form a loop. The flash tank is connected to the fuel gas pipe, and the rich liquid heat exchange coil is connected to the exhaust gas air cooler.

[0019] Compared with the prior art, this utility model has the following advantages and beneficial effects:

[0020] (1) This utility model treats and recycles the waste gas from the triethylene glycol dehydration device, thereby reducing the open flame equipment of the triethylene glycol dehydration device and reducing the engineering investment. It not only reduces the energy consumption required to burn and discharge the waste gas, but also effectively eliminates the pollution of the surrounding environment by the regenerated waste gas, and achieves zero emissions of the natural gas solvent absorption dehydration process.

[0021] (2) This utility model improves the exhaust gas burner, uses fuel gas and compressed air to eject exhaust gas, adapts to the working conditions of changes in stripping gas volume, ensures that the operating pressure during triethylene glycol regeneration is under a slightly positive pressure condition to recover and utilize exhaust gas, and ensures the quality of lean triethylene glycol and the stable operation of the regeneration system.

[0022] (3) By setting up an online exhaust gas analyzer and an online methane analyzer, this utility model can remotely monitor the working status of the burner, while ensuring sufficient purging before start-up and ensuring start-up safety. It realizes the remote start-up function of the burner and the remote monitoring function of the combustion status without the need for personnel to be on duty. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the overall structure of this utility model.

[0024] Figure 2 This is a cross-sectional view of the exhaust gas burner structure.

[0025] The components are as follows: 1-Raw gas filter separator; 2-Triethylene glycol absorption tower; 3-Dry gas / lean liquid heat exchanger; 4-Flash tank; 5-Triethylene glycol solution filter; 6-Triethylene glycol circulating pump; 7-Lean / rich liquid heat exchanger; 8-Rich liquid heat exchange coil; 9-Rich liquid distillation column; 10-Fire-tube reboiler; 11-Lean liquid distillation column; 12-Lean liquid buffer tank; 13-Exhaust gas air cooler; 14-Exhaust gas separator; 15-Exhaust gas burner; 151-Compressed air interface; 152-Fuel gas interface; 153-Exhaust gas interface. 154-Combined Nozzle; 155-Intake Section; 156-Mixing Section; 157-Differentiation Section; 158-Flame Stabilizer; 159-Primary Air Adjustment Plate; 16-Online Exhaust Gas Analyzer; 17-Online Methane Analyzer; 18-Product Gas Pressure Regulating Valve; 19-Flash Tank Level Regulating Valve; 20-Triethylene Glycol Absorber Level Regulating Valve; 21-Fire-Tube Reboiler Temperature Control Regulating Valve; 22-Compressed Air Ejector Control Valve; 23-Compressed Air Flow Meter; 24-Waste Gas Air Cooler Frequency Conversion Control Circuit. Detailed Implementation

[0026] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0027] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0028] Example 1:

[0029] This embodiment provides a triethylene glycol dehydration device for an unattended station, specifically as follows: Figure 1 , Figure 2 As shown, it includes:

[0030] A dehydration system is used to dehydrate natural gas.

[0031] A triethylene glycol regeneration system, connected to the dehydration system, is used for the regeneration and circulation of triethylene glycol; the triethylene glycol regeneration system includes a fire-tube reboiler 10.

[0032] A combustion system, installed on the fire-tube reboiler 10, is used to provide high-temperature conditions; the combustion system includes an exhaust gas burner 15.

[0033] The waste gas recovery and utilization system is used to recover and treat the waste gas generated by the triethylene glycol regeneration system, and supply the treated waste gas to the combustion system for combustion.

[0034] The exhaust gas burner 15 includes a feeding section and a combustion section. The feeding section is connected to the combustion section. The feeding section includes a feeding pipe and a gas supply pipe. The feeding pipe and the gas supply pipe are coaxially arranged. The gas supply pipe is located outside the feeding pipe. One end of the feeding pipe is provided with a compressed air interface 151 and a fuel gas interface 152, and the other end is provided with a combined nozzle 154. An exhaust gas interface 153 is provided on the gas supply pipe. The compressed air interface 151 is connected to a compressed air pipeline, and the fuel gas interface 152 is connected to a fuel gas pipeline. A fire-tube reboiler temperature control regulating valve 21 is installed on the fuel gas pipeline. The fire-tube reboiler temperature control regulating valve 21 changes its opening degree according to the real-time temperature conditions at the fire-tube reboiler 10. The exhaust gas interface 153 is connected to the exhaust gas recovery and utilization system.

[0035] The combustion section includes an intake section 155, a mixing section 156, a diffusion section 157, and a flame stabilizer 158 connected in sequence. The intake section 155 is used to receive the fuel from the feed section and burns it at the flame stabilizer 158. The end of the intake section 155 near the feed section is larger than the diameter of the air supply pipe and there is a gap.

[0036] When the exhaust gas burner 15 is working, if the steam stripping is not activated (exhaust gas volume is small), the fuel gas in the fuel gas pipeline enters the feed pipe through the fuel gas interface 152 and is then injected into the combustion section from the combined nozzle 154. Due to the high-speed flow of the fuel gas, the exhaust gas flowing into the air supply pipe at the exhaust gas interface 153 is successfully injected into the combustion section by negative pressure. At the same time, the gap between the intake section 155 and the air supply pipe is filled with air to supplement the combustion conditions of the fuel gas and exhaust gas. If the steam stripping is activated (exhaust gas volume is small), the main fuel gas volume is insufficient to inject the exhaust gas. Therefore, the compressed air pipeline needs to supply compressed air through the compressed air interface 151 to increase the airflow velocity at the combined nozzle 154, thereby assisting in the injection of exhaust gas.

[0037] By coaxially arranging the feed pipe and the gas supply pipe, with the gas supply pipe located outside the feed pipe, the exhaust gas is ejected from the combined nozzle 154 using the gas from the compressed air interface 151 and the fuel gas interface 152. This ensures that the exhaust gas is fully utilized and that the pressure of triethylene glycol regeneration does not exceed 5 kPa above the triethylene glycol solution filter, thus guaranteeing the quality of lean triethylene glycol and the stable operation of the regeneration system. This solves the problem of tail gas emissions during triethylene glycol regeneration, enabling the recycling and utilization of regeneration exhaust gas. It reduces the energy consumption required for incinerating and discharging this exhaust gas and effectively eliminates the pollution of the surrounding environment caused by the regeneration exhaust gas, achieving zero emissions in the natural gas solvent absorption and dehydration process.

[0038] Example 2:

[0039] This embodiment further extends the above embodiment, specifically as follows: Figure 1 , Figure 2 As shown, the diameter of the pipe at the end where the intake section 155 connects to the mixing section 156 is smaller than the diameter at the end where it connects to the feed section, and the pipe diameter transitions uniformly. Therefore, the intake section 155 can be conical or trumpet-shaped to better ensure that the exhaust gas is successfully ejected.

[0040] Furthermore, a primary air regulating disc 159 is provided axially on the air supply pipe to control the air intake cross-sectional area of ​​the intake section 155. This ensures that the airflow velocity is increased and the air pressure is raised sufficient to successfully eject the exhaust gas.

[0041] Furthermore, the compressed air pipeline is branched, with one branch connected to the compressed air interface 151 and equipped with a compressed air ejector control valve 22, and the other branch connected to the fire-tube reboiler 10 and equipped with a compressed air flow meter 23. Compressed air is used to purge the fire-tube reboiler 10, and the compressed air flow meter 23 ensures sufficient purging air before start-up.

[0042] Furthermore, the fire-tube reboiler 10 is equipped with an online exhaust gas analyzer 16 and an online methane analyzer 17 on its chimney. The exhaust gas analyzer allows for remote real-time monitoring of nitrogen oxide emissions and burner operation. When emissions exceed limits, the system automatically opens the compressed air regulating valve to supply air to the burner nozzles, ensuring more complete combustion and reducing nitrogen oxide emissions to meet national standards. The methane analyzer assesses the burner's combustion status. During start-up, the methane content detected by the methane analyzer 17 determines whether the purging meets start-up requirements, ensuring safe start-up and enabling remote burner start-up and combustion status monitoring.

[0043] The other parts of this embodiment are the same as those in the above embodiments, and will not be described again.

[0044] Example 3:

[0045] This embodiment further extends the above embodiment, specifically as follows: Figure 1 As shown,

[0046] The dehydration system includes a raw gas filter separator 1, a triethylene glycol absorption tower 2, and a dry gas / lean liquid heat exchanger 3. The triethylene glycol absorption tower 2 is connected to the raw gas filter separator 1 and the dry gas / lean liquid heat exchanger 3 respectively. The dry gas / lean liquid heat exchanger 3 is equipped with a product gas pressure regulating valve 18 at its output end.

[0047] After impurities are removed by the raw gas filter separator 1, the raw natural gas enters the lower separation section of the triethylene glycol absorption tower 2. Inside the triethylene glycol absorption tower 2, the natural gas comes into countercurrent contact with the lean triethylene glycol solution from bottom to top, removing saturated water from the natural gas. The dehydrated product gas then passes through the dry gas / lean solution heat exchanger 3 and exchanges heat with the lean triethylene glycol solution therein before being output as product gas. The product gas pressure regulating valve 18 is used to control the output gas pressure.

[0048] The triethylene glycol regeneration system also includes a flash tank 4, a triethylene glycol solution filter 5, a triethylene glycol circulation pump 6, a lean / rich liquid heat exchanger 7, a rich liquid heat exchange coil 8, a rich liquid distillation column 9, a lean liquid distillation column 11, and a lean liquid buffer tank 12. The triethylene glycol absorption tower 2, the rich liquid heat exchange coil 8, the flash tank 4, the triethylene glycol solution filter 5, the lean / rich liquid heat exchanger 7, the lean liquid buffer tank 12, the rich liquid distillation column 9, the fire-tube reboiler 10, the lean liquid distillation column 11, the lean liquid buffer tank 12, the lean / rich liquid heat exchanger 7, the triethylene glycol circulation pump 6, the dry gas / lean liquid heat exchanger 3, and the triethylene glycol absorption tower 2 are connected in sequence to form a loop. The flash tank 4 is connected to the fuel gas pipe, and the rich liquid heat exchange coil 8 is connected to the exhaust gas air cooler 13.

[0049] The triethylene glycol-rich liquid from the bottom of the triethylene glycol absorption tower 2 is depressurized by the triethylene glycol absorption tower level regulating valve 20 and then enters the rich liquid heat exchange coil 8 for heat exchange. It then enters the flash tank 4 for flash evaporation. The flash vapor is sent to the fuel gas pipeline. The triethylene glycol-rich liquid after flash evaporation passes through the triethylene glycol solution filter 5 to remove impurities and degradation products from the solution. It then passes through the flash tank level regulating valve 19 to the lean / rich liquid heat exchanger 7. After heat exchange in the lean / rich liquid heat exchanger 7, it enters the rich liquid distillation column 9 through the lean liquid buffer tank 12. Stripped gas is introduced into the lean triethylene glycol solution in the fire-tube reboiler 10 and comes into contact with the rich triethylene glycol solution in the rich solution distillation column 9. The rich triethylene glycol solution is concentrated in the rich solution distillation column 9 and then enters the fire-tube reboiler 10 to be heated to about 202°C. After passing through the lean solution distillation column 11 and the lean solution buffer tank 12, it enters the lean / rich solution heat exchanger 7 for heat exchange. Then, it is sent to the dry gas / lean solution heat exchanger 3 by the triethylene glycol circulation pump 6 (this pump is an energy recovery pump that converts the energy of the rich solution to increase the pressure of the lean solution). After cooling and heat exchange, it enters the top of the triethylene glycol absorption tower 2, completing the absorption and regeneration cycle of triethylene glycol.

[0050] The waste gas recovery and utilization system includes a waste gas air cooler 13, a waste gas liquid separator 14, and a waste gas air cooler frequency conversion control circuit 24. One end of the waste gas air cooler 13 is connected to the triethylene glycol regeneration system, and the other end is connected to the waste gas liquid separator 14. The waste gas liquid separator 14 is connected to the waste gas interface 153. The waste gas air cooler frequency conversion control circuit 24 is used to control the power of the waste gas air cooler 13.

[0051] The flash vapor in flash tank 4 is cooled by waste gas air cooler 13, and then separated into gas and liquid in waste gas separator 14. The waste gas flows to waste gas interface 153 for reuse.

[0052] The other parts of this embodiment are the same as those in the above embodiments, and will not be described again.

[0053] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model in any way. Any simple modifications or equivalent changes made to the above embodiments based on the technical essence of the present utility model shall fall within the protection scope of the present utility model.

Claims

1. A triethylene glycol dehydration device for an unattended station, characterized in that, include: A dehydration system is used to dehydrate natural gas. A triethylene glycol regeneration system, connected to the dehydration system, is used for the regeneration and circulation of triethylene glycol; the triethylene glycol regeneration system includes a fire-tube reboiler (10); A combustion system, installed on the fire-tube reboiler (10), is used to provide high-temperature conditions; the combustion system includes an exhaust gas burner (15); The waste gas recovery and utilization system is used to recover and treat the waste gas generated by the triethylene glycol regeneration system, and supply the treated waste gas to the combustion system for combustion. The exhaust gas burner (15) includes a feeding section and a combustion section. The feeding section is connected to the combustion section. The feeding section includes a feeding pipe and a gas supply pipe. The feeding pipe and the gas supply pipe are coaxially arranged. The gas supply pipe is located outside the feeding pipe. One end of the feeding pipe is provided with a compressed air interface (151) and a fuel gas interface (152). The other end is provided with a combined nozzle (154). The gas supply pipe is provided with an exhaust gas interface (153). The compressed air interface (151) is connected to a compressed air pipeline. The fuel gas interface (152) is connected to a fuel gas pipeline. The exhaust gas interface (153) is connected to the exhaust gas recovery and utilization system.

2. The triethylene glycol dehydration device for an unmanned station according to claim 1, characterized in that: The combustion section includes an intake section (155), a mixing section (156), a diffusion section (157), and a flame stabilizer (158) connected in sequence. The intake section (155) is used to receive fuel from the feed section and burns at the flame stabilizer (158). The end of the intake section (155) near the feed section is larger than the diameter of the air supply pipe and has a gap.

3. The triethylene glycol dehydration device for an unmanned station according to claim 2, characterized in that: The diameter of the end of the air intake section (155) connected to the mixing section (156) is smaller than the diameter of the end of the air intake section connected to the feed section, and the diameter transitions uniformly.

4. The triethylene glycol dehydration device for an unmanned station according to claim 2, characterized in that: A primary air regulating plate (159) is provided along the axial direction on the air supply pipe to control the air intake cross-sectional area of ​​the air intake section (155).

5. The triethylene glycol dehydration device for an unmanned station according to claim 4, characterized in that: The compressed air pipeline is provided with a branch, one of which is connected to the compressed air interface (151) and is provided with a compressed air ejector control valve (22), and the other is connected to the fire tube reboiler (10) and is provided with a compressed air flow meter (23).

6. The triethylene glycol dehydration device for an unmanned station according to claim 5, characterized in that: The fire-tube reboiler (10) is equipped with an online tail gas analyzer (16) and an online methane analyzer (17).

7. A triethylene glycol dehydration device for an unattended station according to any one of claims 1-6, characterized in that: The waste gas recovery and utilization system includes a waste gas air cooler (13), a waste gas liquid separator (14), and a waste gas air cooler frequency conversion control circuit (24). One end of the waste gas air cooler (13) is connected to the triethylene glycol regeneration system, and the other end is connected to the waste gas liquid separator (14). The waste gas liquid separator (14) is connected to the waste gas interface (153). The waste gas air cooler frequency conversion control circuit (24) is used to control the power of the waste gas air cooler (13).

8. The triethylene glycol dehydration device for an unmanned station according to claim 7, characterized in that: The dehydration system includes a raw gas filter separator (1), a triethylene glycol absorption tower (2), and a dry gas / lean liquid heat exchanger (3). The triethylene glycol absorption tower (2) is connected to the raw gas filter separator (1) and the dry gas / lean liquid heat exchanger (3) respectively. The dry gas / lean liquid heat exchanger (3) is equipped with a product gas pressure regulating valve (18) at its output end.

9. The triethylene glycol dehydration device for an unmanned station according to claim 8, characterized in that: The triethylene glycol regeneration system also includes a flash tank (4), a triethylene glycol solution filter (5), a triethylene glycol circulation pump (6), a lean / rich liquid heat exchanger (7), a rich liquid heat exchange coil (8), a rich liquid distillation column (9), a lean liquid distillation column (11), and a lean liquid buffer tank (12). The triethylene glycol absorption tower (2), the rich liquid heat exchange coil (8), the flash tank (4), the triethylene glycol solution filter (5), the lean / rich liquid heat exchanger (7), the lean liquid buffer tank (12), the rich liquid distillation column (9), the fire-tube reboiler (10), the lean liquid distillation column (11), the lean liquid buffer tank (12), the lean / rich liquid heat exchanger (7), the triethylene glycol circulation pump (6), the dry gas / lean liquid heat exchanger (3), and the triethylene glycol absorption tower (2) are connected in sequence to form a loop. The flash tank (4) is connected to the fuel gas pipe, and the rich liquid heat exchange coil (8) is connected to the exhaust gas air cooler (13).

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