CN107916151B - Dehydration system and method for natural gas - Google Patents
Dehydration system and method for natural gas Download PDFInfo
- Publication number
- CN107916151B CN107916151B CN201711491309.5A CN201711491309A CN107916151B CN 107916151 B CN107916151 B CN 107916151B CN 201711491309 A CN201711491309 A CN 201711491309A CN 107916151 B CN107916151 B CN 107916151B
- Authority
- CN
- China
- Prior art keywords
- enters
- separator
- outlet
- heat exchanger
- tower
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G, C10K; LIQUEFIED PETROLEUM GAS; ADDING MATERIALS TO FUELS OR FIRES TO REDUCE SMOKE OR UNDESIRABLE DEPOSITS OR TO FACILITATE SOOT REMOVAL; FIRELIGHTERS
- C10L3/00—Gaseous fuels; Natural gas; Synthetic natural gas obtained by processes not covered by subclass C10G, C10K; Liquefied petroleum gas
- C10L3/06—Natural gas; Synthetic natural gas obtained by processes not covered by C10G, C10K3/02 or C10K3/04
- C10L3/10—Working-up natural gas or synthetic natural gas
- C10L3/101—Removal of contaminants
- C10L3/106—Removal of contaminants of water
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
- B01D53/26—Drying gases or vapours
- B01D53/263—Drying gases or vapours by absorption
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2252/00—Absorbents, i.e. solvents and liquid materials for gas absorption
- B01D2252/20—Organic absorbents
- B01D2252/202—Alcohols or their derivatives
- B01D2252/2021—Methanol
Landscapes
- Chemical & Material Sciences (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Analytical Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Drying Of Gases (AREA)
Abstract
The invention provides a dehydration system and a dehydration method for natural gas, wherein the system comprises a first separator, a first heat exchanger, a first absorption tower, a second heat exchanger, a second separator, a second absorption tower, a third separator, a first mixer, a water scrubber, a second distributor, a molecular sieve dryer and a dehydration tower; the lower end of the first separator is provided with a first separator discharge outlet; the outlet of the upper end of the first separator is connected with a first heat exchanger, the outlet of the lower end of the first heat exchanger is communicated with the inlet of the lower end of a first absorption tower, the upper end of the first absorption tower is communicated with the inlet of the upper part of the first heat exchanger, and the outlet of the upper part of the first heat exchanger is connected with a dehydrated natural gas collecting pipeline; the invention cools the methanol at low temperature, then uses the cooled methanol as a circulating agent to absorb the water in the natural gas, and adopts the system to realize the water removal rate of 99.99% in the natural gas, thereby completely realizing deep dehydration and corrosion prevention.
Description
Technical Field
The invention belongs to the field of natural gas, and particularly relates to a dehydration system and method for natural gas.
Background
In general, natural gas dehydration refers to the process of removing saturated water vapor from natural gas or removing dissolved water from Natural Gas Liquids (NGL). The purpose of dehydration is: 1) Preventing hydrate and liquid water from occurring during processing and storage. 2) Meets the quality index of the water content (or the water dew point) of the natural gas. 3) Corrosion is prevented. Conventional dehydration methods in natural gas processing include low temperature and absorption methods. The cryogenic process is to cool natural gas to a low temperature below the dew point of hydrocarbons to obtain a portion of liquid hydrocarbons rich in heavier hydrocarbons (i.e., natural gas condensate or condensate) and separate it from the gas at this low temperature, and is also referred to as a condensate separation process. The dehydration by the absorption method is based on the absorption principle, and a hydrophilic liquid is adopted to contact with natural gas in countercurrent, so that the moisture in the gas is absorbed to achieve the purpose of removal. The hydrophilic liquid used for dehydration is called a dehydration absorber or liquid desiccant, also referred to simply as a desiccant. However, the natural gas treated by the method is not thoroughly dehydrated, and the problems of pipeline corrosion and the like are caused by the incomplete dehydration.
Disclosure of Invention
In order to solve the problem of incomplete dehydration of the existing natural gas, the invention provides a dehydration system and a dehydration method for the natural gas, wherein the system carries out low-temperature cooling on methanol, then the methanol is used as a circulating agent to absorb water in the natural gas, and the dehydration rate of the natural gas in the system reaches 99.99 percent, so that deep dehydration is completely realized.
A dehydration system for natural gas, comprising a first separator, a first heat exchanger, a first absorption tower, a second heat exchanger, a second separator, a second absorption tower, a third separator, a first mixer, a water scrubber, a second distributor, a molecular sieve dryer and a dehydration tower; the lower end of the first separator is provided with a first separator discharge outlet; the outlet of the upper end of the first separator is connected with a first heat exchanger, the outlet of the lower end of the first heat exchanger is communicated with the inlet of the lower end of a first absorption tower, the upper end of the first absorption tower is communicated with the inlet of the upper part of the first heat exchanger, and the outlet of the upper part of the first heat exchanger is connected with a dehydrated natural gas collecting pipeline; the outlet at the lower end of the first absorption tower is communicated with the inlet at the lower end of the second heat exchanger, the outlet at the upper end of the second heat exchanger is communicated with the inlet at the upper part of the first absorption tower through a pipeline, and a third mixer, a second cooler, a second methanol pump and a third circulator are sequentially arranged between the second heat exchanger and the first absorption tower; the outlet at the lower end of the second heat exchanger is communicated with a second separator, the outlet at the lower end of the second separator is communicated with an inlet at the upper part of a second absorption tower, a first methanol inlet is arranged at the upper part of the second absorption tower, the outlet at the lower end of the second absorption tower is communicated with an inlet at the upper part of a molecular sieve dryer, and a first distributor and a second distributor are sequentially arranged between the outlet at the lower end of the second absorption tower and the inlet at the upper part of the molecular sieve dryer; a heater and a first circulator are sequentially arranged between an upper outlet of the first distributor and a lower inlet of the second absorption tower; the outlet at the upper end of the molecular sieve dryer is communicated with the inlet at the upper part of the second heat exchanger through a pipeline, a second mixer is arranged on the pipeline, and the inlet at the upper part of the second mixer is communicated with the outlet at the upper part of the second distributor; the outlet at the upper end of the second absorption tower is communicated with a third separator, the outlet at the upper end of the third separator and the outlet at the upper end of the second separator are respectively communicated with a first mixer, and the outlet of the first mixer is communicated with the inlet at the lower part of the water scrubber; the upper end of the water washing tower is provided with a water washing tower discharge outlet, and the upper part of the water washing tower is provided with a water inlet; a third heat exchanger is arranged between the outlet at the lower end of the water washing tower and the dehydration tower; the lower end of the dehydration tower is provided with a reboiler; the outlet at the upper end of the dehydration tower is connected with a fourth separator, the upper end of the fourth separator is provided with a fourth separator discharge outlet, the outlet at the lower end of the fourth separator is connected with a third distributor, and a first methanol pump is arranged between the fourth separator and the third distributor; the outlet at the lower end of the third distributor is communicated with the inlet at the upper part of the dehydration tower through a pipeline, and a second circulator is arranged on the pipeline; the third distributor upper outlet communicates with the third mixer upper inlet.
The third heat exchanger is provided with a third heat exchanger discharge port; the inlet at the upper end of the third heat exchanger is communicated with the outlet at the lower end of the reboiler.
A throttle valve is arranged between the outlet at the lower end of the first absorption tower and the inlet at the lower end of the second heat exchanger.
The lower end of the molecular sieve dryer is provided with a molecular sieve dryer discharge outlet.
A first cooler is arranged between the dehydration tower and the fourth separator.
The third mixer is provided with a second methanol inlet.
The lower end is provided with a third separator discharge outlet.
The dehydration method for the natural gas comprises the following specific steps:
the raw natural gas enters a first separator for first separation; the separated gas enters a first heat exchanger for heat exchange, enters the bottom of a first absorption tower after heat exchange, and fully contacts with methanol from the top of the first absorption tower;
mixing methanol from a second methanol inlet with two material flows which enter a third mixer, cooling the mixed material flows in a second cooler, pressurizing the material flows in a second methanol pump after the cooler, circulating the material flows in a third circulator, and pumping the material flows into the top of a first absorption tower;
the material flow coming out of the top of the first absorption tower enters a first heat exchanger to exchange heat with raw material natural gas sufficiently, and purified gas is output through a dehydrated natural gas collecting pipe line after heat exchange;
the material flow coming out of the bottom of the first absorption tower enters a throttle valve to throttle, the material flow coming out of the throttle valve enters a second heat exchanger to exchange heat, and the discharged material flow enters a second separator to carry out secondary separation, and enters the second absorption tower after separation; the supplemented methanol enters the top of the second absorption tower through the first methanol inlet; after the countercurrent contact in the second absorption tower is carried out for full absorption, the material flow coming out from the bottom of the tower enters a first distributor and is divided into two parts, one material flow enters a heater for heating, and the heated material flow enters the bottom of the second absorption tower through a first circulator; the other stream enters a second distributor and is divided into two streams, wherein one stream enters a molecular sieve dryer for drying, and the dried stream is mixed with the stream from the second distributor and enters a second mixer for secondary mixing, the mixed stream enters a second heat exchanger for heat exchange, and the stream after heat exchange enters a third mixer;
the material flow from the top of the second absorption tower enters a third separator for third separation, and the gas-phase material flow from the top of the third separator is mixed with the gas-phase material flow from the top of the second separator in a first mixer; the mixed material flow enters the bottom of a water washing tower; the material flowing water enters the top of the water washing tower through a water inlet at the upper part of the water washing tower; the two streams are reversely contacted and fully absorbed; the material flow from the top of the water washing tower is discharged through the discharge outlet of the water washing tower; the material flow coming out of the bottom of the water washing tower enters a third heat exchanger for full heat exchange, and the material flow coming out enters the middle part of the dehydrating tower; the temperature of the dehydration tower is controlled at 98-102 ℃ and the pressure is controlled at 0.10-0.12MPa; the material flow coming out from the bottom of the dehydration tower enters a third heat exchanger for heat exchange, and the discharged material flow is discharged through a discharge outlet of the third heat exchanger;
the material flow coming out from the top of the dehydration tower firstly enters a first cooler for cooling, then enters a fourth separator for separating gas phase, the separated liquid methanol is pressurized by a first methanol pump, and the pressurized material flow enters a third distributor; a part of the material flow passes through a second circulator to enter the top of the dehydration tower, and the other part of the material flow enters a third mixer;
the material flow coming out of the bottom of the dehydration tower enters a reboiler, and the material flow coming out of the reboiler enters a third heat exchanger to provide heat for the material flow coming out of the bottom of the water washing tower;
and (3) mixing three material flows entering a mixer, cooling the mixed material flows entering a second cooler, pressurizing the mixed material flows entering a second methanol pump, and circularly pumping the pressurized material flows into a third circulator into a first absorption tower.
The beneficial effects of the invention are as follows:
the invention can be widely applied to natural gas treatment plants. The invention cools the methanol at low temperature, then uses the cooled methanol as a circulating agent to absorb the water in the natural gas, and adopts the system to realize the deep dehydration completely, wherein the water removal rate in the natural gas reaches 99.99 percent.
The invention is further described below with reference to the drawings of the embodiments.
Drawings
FIG. 1 is a schematic diagram of an embodiment of a novel dewatering process and system.
In the figure: 1. raw natural gas; 2. a first separator; 3. a first heat exchanger; 4. a first absorption tower; 5. a throttle valve; 6. a second heat exchanger; 7. a second separator; 8. a first methanol inlet; 9. a second absorption tower; 10. a third separator; 11. a first mixer; 12. a water washing tower; 13. a heater; 14. a first dispenser; 15. a first circulator; 16. a second dispenser; 17. a molecular sieve dryer; 18. a second mixer; 19. a third heat exchanger; 20. a second circulator; 21. a first cooler; 22. a dehydration tower; 23. a reboiler; 24. a third dispenser; 25. a fourth separator; 26. a first methanol pump; 27. a third mixer; 28. a second cooler; 29. a second methanol pump; 30. a fourth circulator; 31. a dehydrated natural gas collection line; 32. a second methanol inlet; 33. a water inlet; 34. a third separator discharge outlet; 35. a third heat exchanger discharge port; 36. a water scrubber discharge outlet; 37. a molecular sieve dryer discharge outlet; 38. a fourth separator discharge outlet; 39. a first separator discharge.
Detailed Description
Example 1:
in order to solve the problem of incomplete dehydration of the existing natural gas, the invention provides a dehydration system and a dehydration method for the natural gas, which are shown in figure 1, wherein the system carries out low-temperature cooling on methanol, then the methanol is used as a circulating agent to absorb water in the natural gas, and the dehydration rate of the natural gas in the system reaches 99.99 percent, so that deep dehydration is completely realized.
A dehydration system for natural gas, comprising a first separator 2, a first heat exchanger 3, a first absorption tower 4, a second heat exchanger 6, a second separator 7, a second absorption tower 9, a third separator 10, a first mixer 11, a water scrubber 12, a second distributor 16, a molecular sieve dryer 17 and a dehydration tower 22; the lower end of the first separator 2 is provided with a first separator discharge outlet 39; the upper outlet of the first separator 2 is connected with the first heat exchanger 3, the lower outlet of the first heat exchanger 3 is communicated with the lower inlet of the first absorption tower 4, the upper end of the first absorption tower 4 is communicated with the upper inlet of the first heat exchanger 3, and the upper outlet of the first heat exchanger 3 is connected with a dehydrated natural gas collecting pipeline 31; the outlet at the lower end of the first absorption tower 4 is communicated with the inlet at the lower end of the second heat exchanger 6, the outlet at the upper end of the second heat exchanger 6 is communicated with the inlet at the upper part of the first absorption tower 4 through a pipeline, and a third mixer 27, a second cooler 28, a second methanol pump 29 and a third circulator 30 are sequentially arranged between the second heat exchanger 6 and the first absorption tower 4; the outlet at the lower end of the second heat exchanger 6 is communicated with a second separator 7, the outlet at the lower end of the second separator 7 is communicated with the inlet at the upper part of a second absorption tower 9, the upper part of the second absorption tower 9 is provided with a first methanol inlet 8, the outlet at the lower end of the second absorption tower 9 is communicated with the inlet at the upper part of a molecular sieve dryer 17, and a first distributor 14 and a second distributor 16 are sequentially arranged between the outlet at the lower end of the second absorption tower 9 and the inlet at the upper part of the molecular sieve dryer 17; a heater 13 and a first circulator 15 are sequentially arranged between the upper outlet of the first distributor 14 and the lower inlet of the second absorption tower 9; the outlet of the upper end of the molecular sieve dryer 17 is communicated with the inlet of the upper part of the second heat exchanger 6 through a pipeline, a second mixer 18 is arranged on the pipeline, and the inlet of the upper part of the second mixer 18 is communicated with the outlet of the upper part of the second distributor 16; the outlet at the upper end of the second absorption tower 9 is communicated with a third separator 10, the outlet at the upper end of the third separator 10 and the outlet at the upper end of the second separator 7 are respectively communicated with a first mixer 11, and the outlet of the first mixer 11 is communicated with the inlet at the lower part of a water washing tower 12; the upper end of the water scrubber 12 is provided with a water scrubber outlet 36, and the upper part of the water scrubber 12 is provided with a water inlet 33; a third heat exchanger 19 is arranged between the outlet of the lower end of the water scrubber 12 and the dehydration tower 22; the lower end of the dehydration tower 22 is provided with a reboiler 23; the outlet at the upper end of the dehydration tower 22 is connected with a fourth separator 25, the upper end of the fourth separator 25 is provided with a fourth separator discharge outlet 38, the outlet at the lower end of the fourth separator 25 is connected with a third distributor 24, and a first methanol pump 26 is arranged between the fourth separator 25 and the third distributor 24; the outlet at the lower end of the third distributor 24 is communicated with the inlet at the upper part of the dehydration tower 22 through a pipeline, and the pipeline is provided with a second circulator 20; the upper outlet of the third distributor 24 communicates with the upper inlet of the third mixer 27.
The system provided by the invention can be widely applied to natural gas treatment plants and the like. The method adopts internationally well known HYSYS software to carry out deep simulation, adjusts parameters and optimizes parameters, the moisture removal rate in the natural gas of the system reaches 99.99%, and deep dehydration is completely realized.
Example 2:
based on the above embodiment, in this embodiment, the third heat exchanger 19 is provided with a third heat exchanger outlet 35; the upper inlet of the third heat exchanger 19 is communicated with the lower outlet of the reboiler 23.
A throttle valve 5 is arranged between the outlet at the lower end of the first absorption tower 4 and the inlet at the lower end of the second heat exchanger 6.
The lower end of the molecular sieve dryer 17 is provided with a molecular sieve dryer outlet 37.
A first cooler 21 is arranged between the dehydration tower 22 and the fourth separator 25.
The third mixer 27 is provided with a second methanol inlet 32.
The lower end of the housing 10 is provided with a third separator discharge 34.
The dehydration method for the natural gas comprises the following specific steps:
the raw natural gas 1 enters a first separator 2 for first separation; the separated gas enters a first heat exchanger 3 for heat exchange, enters the bottom of a first absorption tower 4 after heat exchange, and fully contacts with methanol from the top of the first absorption tower 4;
mixing methanol from a second methanol inlet 32 with two streams which enter a third mixer 27, cooling the mixed stream by a second cooler 28, pressurizing the cooled stream by a second methanol pump 29, circulating the pressurized stream by a third circulator 30, and pumping the pressurized stream to the top of the first absorption tower 4;
the material flow coming out from the top of the first absorption tower 4 enters a first heat exchanger 3 to exchange heat with the raw material natural gas 1 sufficiently, and purified gas is output through a dehydrated natural gas collecting pipeline 31 after heat exchange;
the material flow coming out of the bottom of the first absorption tower 4 enters a throttle valve 5 to throttle, the material flow coming out of the throttle valve 5 enters a second heat exchanger 6 to exchange heat, and the discharged material flow enters a second separator 7 to carry out secondary separation, and enters a second absorption tower 9 after separation; the supplemented methanol enters the top of the second absorption tower 9 through the first methanol inlet 8; after the countercurrent contact in the second absorption tower 9 is carried out for full absorption, the material flow coming out from the tower bottom enters a first distributor 14 and is split into two streams, one stream enters a heater 13 for heating, and the heated material flow enters the bottom of the second absorption tower 9 through a first circulator 15; the other stream enters a second distributor 16 and is divided into two streams, wherein one stream enters a molecular sieve dryer 17 for drying, the dried stream is mixed with the stream from the second distributor 16 and enters a second mixer 18 for secondary mixing, the mixed stream enters a second heat exchanger 6 for heat exchange, and the heat exchanged stream enters a third mixer 27;
the stream coming out from the top of the second absorption column 9 enters a third separator 10 for a third separation, and the gas phase stream coming out from the top of the third separator 10 is mixed with the gas phase stream coming out from the top of the second separator 7 in a first mixer 11; the mixed material flow enters the bottom of the water scrubber 12; the material flowing water enters the top of the water scrubber 12 through a water inlet 33 at the upper part of the water scrubber 12; the two streams are reversely contacted and fully absorbed; the stream exiting the top of the water wash column 12 is discharged through a water wash column discharge outlet 36; the material flow coming out of the bottom of the water washing tower 12 enters a third heat exchanger 19 for full heat exchange, and the material flow coming out enters the middle part of a dehydrating tower 22; the temperature of the dehydration tower 22 is controlled between 98 and 102 ℃ and the pressure is controlled between 0.10 and 0.12MPa; the material flow coming out from the bottom of the dehydration tower 22 enters the third heat exchanger 19 for heat exchange, and the discharged material flow is discharged through a third heat exchanger discharge outlet 35;
the material flow coming out from the top of the dehydrating tower 22 firstly enters the first cooler 21 for cooling, and enters the fourth separator 25 for separating gas phase after cooling, the separated liquid methanol is pressurized by the first methanol pump 26, and the pressurized material flow enters the third distributor 24; a part of the material flow passes through the second circulator 20 to enter the top of the dehydration column 22, and the other part of the material flow enters the third mixer 27;
the stream from the bottom of the dehydration column 22 enters a reboiler 23 and the stream from the reboiler 23 enters a third heat exchanger 19 to provide heat to the stream from the bottom of the water wash column 12;
the three streams entering the mixer 27 are mixed, and the mixed streams enter the second cooler 28 for cooling, then enter the second methanol pump 29 for pressurizing, enter the third circulator 30 after pressurizing, and are circularly injected into the first absorption tower 4.
The invention is implemented as follows:
the components of the raw material natural gas 1 are methane, ethane, propane, nitrogen, carbon dioxide, hydrogen sulfide and water, and the raw material natural gas enters a first separator 2 for first separation. Separating out gas with the temperature of 24.27 ℃ and the pressure of 5.8MPa, entering a first heat exchanger 3 for heat exchange, and enabling the gas with the temperature of-22 ℃ and the pressure of 5.8MPa to enter the bottom of a first absorption tower 4 after heat exchange so as to fully contact methanol from the top of the first absorption tower 4;
mixing methanol at 25 ℃ from a second methanol inlet 32 and 0.12MPa with two material flows in other systems, entering a third mixer 27, entering a second cooler 28 at-26.6 ℃ and 0.115MPa, cooling, entering a second methanol pump 29 for pressurizing at-33 ℃ and 0.115MPa, entering a third circulator 30 for circulating, and entering the top of a first absorption tower 4;
the temperature of the material flow coming out from the top of the first absorption tower 4 is minus 29 ℃, the pressure is 5.8MPa, the material flow enters the first heat exchanger 3 to exchange heat with the raw material gas 1 fully, and the purified gas after heat exchange is delivered to the temperature of 20.4 ℃ and the pressure is 5.8MPa through the dehydrated natural gas collecting pipeline 31;
the temperature of the material flow coming out of the bottom of the first absorption tower 4 is minus 28 ℃, the pressure of 5.8MPa enters a throttle valve 5 to throttle, the temperature of the material flow coming out of the throttle valve 5 is minus 29.2 ℃, the pressure of 0.6MPa enters a second heat exchanger 6 to exchange heat, the temperature of the material flow coming out is 40 ℃, the pressure of 0.6MPa enters a second separator 7 to carry out secondary separation, and the temperature of 40 ℃ and the pressure of 0.6MPa after separation enter a second absorption tower 9. The additional methanol enters the top of the second absorption tower 9 through the first methanol inlet 8 at a temperature of 40 ℃ and a pressure of 0.11 MPa. After the countercurrent contact in the second absorption tower 9 is carried out, the material flow with the temperature of 43.4 ℃ and the pressure of 0.12MPa at the bottom of the tower enters the first distributor 14 and is divided into two parts, one part with the temperature of 43.4 ℃ and the pressure of 0.12MPa enters the heater 13 for heating, and the heated material flow with the temperature of 70.1 ℃ and the pressure of 0.12MPa enters the bottom of the second absorption tower 9 through the first circulator 15. The other material flow enters the second distributor 16 at the temperature of 43.4 ℃ and the pressure of 0.12MPa, and is divided into two material flows, wherein one material flow enters the molecular sieve dryer 17 for drying, and is mixed with the material flow from the second distributor 16 and enters the second mixer 18 for secondary mixing, the mixed material flow at the temperature of 43.4 ℃ and the pressure of 0.12MPa enters the second heat exchanger 6 for heat exchange, and the material flow at the temperature of-26.7 ℃ and the pressure of 0.12MPa enter the third mixer 27.
The temperature of the material flow coming out from the top of the second absorption tower 9 is 39.4 ℃, the pressure of 0.11MPa enters the third separator 10 for three times of separation, the temperature of the top gas phase material flow is 39.4 ℃, the pressure of 0.11MPa is mixed with the temperature of the gas phase material flow coming out from the top of the second separator 7 at 40 ℃, and the pressure of 0.6MPa is mixed in the first mixer 11; the mixed material flow enters the bottom of the water scrubber 12 at the temperature of 39.9 ℃ and the pressure of 0.11 MPa. The material flowing water enters the top of the water scrubber 12 through a water inlet 33 at the upper part of the water scrubber 12 at the temperature of 75 ℃ and the pressure of 0.11MPa; the two streams are reversely contacted and fully absorbed; the stream exiting the top of the water wash column 12 is discharged through a water wash column discharge outlet 36; the main component is methane.
The temperature of the material flow coming out from the bottom of the water scrubber 12 is 32.4 ℃, the pressure of 0.11MPa enters the third heat exchanger 19 for full heat exchange, the temperature of the material flow coming out is 75 ℃, and the pressure of 0.11MPa enters the middle part of the dehydration tower 22; the temperature of the dehydration tower 22 is controlled at 100 ℃ and the pressure is controlled at 0.11MPa; the material flow coming out from the bottom of the dehydration tower 22 enters the third heat exchanger 19 for heat exchange at the temperature of 96.7 ℃ and the pressure of 0.11MPa, and the discharged material flow is discharged at the temperature of 45.4 ℃ through the discharge outlet 35 of the third heat exchanger and the pressure of 0.11MPa, and the main component is liquid water.
The main component of the material flow coming out from the top of the dehydration tower 22 is that methanol with the temperature of 67.2 ℃ and the pressure of 0.11MPa firstly enters a first cooler 21 for cooling, the cooled material flow with the temperature of 40 ℃ and the pressure of 0.1MPa enters a fourth separator 25 for separating gas phase, liquid methanol with the temperature of 40 ℃ and the pressure of 0.1MPa is pressurized by a first methanol pump 26, and the pressurized material flow with the temperature of 40.1 ℃ and the pressure of 0.4MPa enters a third distributor 24; a portion of the stream passes through the second circulator 20 into the top of the dehydration column 22 and another portion of the stream passes into the third mixer 27.
The main component of the stream exiting reboiler 23 is a stream having a water temperature of 96.7 c and a pressure of 0.11MPa entering third heat exchanger 19 to provide heat to the bottom of water scrubber 12.
The three streams entering the mixer 27 are mixed, the mixed stream enters the cooler 2828 for cooling, then enters the second methanol pump 29 for pressurizing, enters the third circulator 30 after pressurizing, and is circularly pumped into the first absorption tower 4.
The temperature involved in the invention can float up and down by 2 ℃, wherein the pressure can float up and down by 0.01MPa. The components and their structures involved in the present invention are all of the prior art and are commercially available, and will not be described in detail.
The following table 1 is a raw natural gas composition table; table 2 is a purified natural gas composition table.
TABLE 1 raw Natural gas composition Table
| Component (A) | CH 4 | C 2 H 6 | N 2 | CO 2 | H 2 O | C 3 H 8 | H 2 S |
| Content of | 91.9% | 0.5% | 0.2% | 5.4% | 2% | 0 | 0 |
TABLE 2 purified natural gas composition table
| Component (A) | CH 4 | C 2 H 6 | N 2 | CO 2 | H 2 O | C 3 H 8 | H 2 S |
| Content of | 94.8% | 0.5% | 0.2% | 5.4% | 0 | 0 | 0 |
From the above table, it can be seen that the moisture in the raw natural gas is completely removed after the water in the natural gas is treated by the system provided by the invention. The invention effectively prevents hydrate and liquid water from occurring in the process of treatment, storage and transportation. And simultaneously meets the quality index of the water content (or the water dew point) of the natural gas. The invention cools the methanol at low temperature, then uses the cooled methanol as a circulating agent to absorb the water in the natural gas, and adopts the system to realize the water removal rate of 99.99% in the natural gas, thereby completely realizing deep dehydration and corrosion prevention.
The foregoing examples are merely illustrative of the present invention and are not intended to limit the scope of the present invention, and all designs that are the same or similar to the present invention are within the scope of the present invention. Devices and structures not described in detail in the present invention are all prior art, and will not be described in detail.
Claims (5)
1. A dehydration system for natural gas, characterized by: the device comprises a first separator (2), a first heat exchanger (3), a first absorption tower (4), a second heat exchanger (6), a second separator (7), a second absorption tower (9), a third separator (10), a first mixer (11), a water washing tower (12), a second distributor (16), a molecular sieve dryer (17) and a dehydration tower (22); the lower end of the first separator (2) is provided with a first separator discharge outlet (39); the upper outlet of the first separator (2) is connected with the first heat exchanger (3), the lower outlet of the first heat exchanger (3) is communicated with the lower inlet of the first absorption tower (4), the upper end of the first absorption tower (4) is communicated with the upper inlet of the first heat exchanger (3), and the upper outlet of the first heat exchanger (3) is connected with a dehydrated natural gas collecting pipeline (31); the outlet at the lower end of the first absorption tower (4) is communicated with the inlet at the lower end of the second heat exchanger (6), the outlet at the upper end of the second heat exchanger (6) is communicated with the inlet at the upper part of the first absorption tower (4) through a pipeline, and a third mixer (27), a second cooler (28), a second methanol pump (29) and a third circulator (30) are sequentially arranged between the second heat exchanger (6) and the first absorption tower (4); the outlet at the lower end of the second heat exchanger (6) is communicated with the second separator (7), the outlet at the lower end of the second separator (7) is communicated with the inlet at the upper part of the second absorption tower (9), the upper part of the second absorption tower (9) is provided with a first methanol inlet (8), the outlet at the lower end of the second absorption tower (9) is communicated with the inlet at the upper part of the molecular sieve dryer (17), and a first distributor (14) and a second distributor (16) are sequentially arranged between the outlet at the lower end of the second absorption tower (9) and the inlet at the upper part of the molecular sieve dryer (17); a heater (13) and a first circulator (15) are sequentially arranged between the upper outlet of the first distributor (14) and the lower inlet of the second absorption tower (9); the outlet at the upper end of the molecular sieve dryer (17) is communicated with the inlet at the upper part of the second heat exchanger (6) through a pipeline, a second mixer (18) is arranged on the pipeline, and the inlet at the upper part of the second mixer (18) is communicated with the outlet at the upper part of the second distributor (16); the outlet at the upper end of the second absorption tower (9) is communicated with a third separator (10), the outlet at the upper end of the third separator (10) and the outlet at the upper end of the second separator (7) are respectively communicated with a first mixer (11), and the outlet of the first mixer (11) is communicated with the inlet at the lower part of the water washing tower (12); the upper end of the water washing tower (12) is provided with a water washing tower discharge outlet (36), and the upper part of the water washing tower (12) is provided with a water inlet (33); a third heat exchanger (19) is arranged between the outlet at the lower end of the water washing tower (12) and the dehydrating tower (22); the lower end of the dehydration tower (22) is provided with a reboiler (23); the outlet at the upper end of the dehydration tower (22) is connected with a fourth separator (25), the upper end of the fourth separator (25) is provided with a fourth separator discharge outlet (38), the outlet at the lower end of the fourth separator (25) is connected with a third distributor (24), and a first methanol pump (26) is arranged between the fourth separator (25) and the third distributor (24); the outlet at the lower end of the third distributor (24) is communicated with the inlet at the upper part of the dehydrating tower (22) through a pipeline, and a second circulator (20) is arranged on the pipeline; an upper outlet of the third distributor (24) is communicated with an upper inlet of the third mixer (27);
a third heat exchanger discharge outlet (35) is arranged on the third heat exchanger (19); the inlet at the upper end of the third heat exchanger (19) is communicated with the outlet at the lower end of the reboiler (23), a throttle valve (5) is arranged between the outlet at the lower end of the first absorption tower (4) and the inlet at the lower end of the second heat exchanger (6), and a molecular sieve dryer outlet (37) is arranged at the lower end of the molecular sieve dryer (17).
2. A dehydration system for natural gas as in claim 1 wherein: a first cooler (21) is arranged between the dehydration tower (22) and the fourth separator (25).
3. A dehydration system for natural gas as in claim 1 wherein: the third mixer (27) is provided with a second methanol inlet (32).
4. A dehydration system for natural gas as in claim 1 wherein: the lower end of the third separator (10) is provided with a third separator discharge outlet (34).
5. The dehydration system for natural gas according to any one of claims 1 to 4 provides a dehydration method for natural gas, characterized in that: the method comprises the following specific steps:
the raw natural gas (1) enters a first separator (2) for first separation; the separated gas enters a first heat exchanger (3) for heat exchange, enters the bottom of a first absorption tower (4) after heat exchange, and is fully contacted with methanol from the top of the first absorption tower (4);
the methanol is mixed with two material flows which enter a third mixer (27) from a second methanol inlet (32), the mixed material flows enter a second cooler (28) for cooling, after the cooler, enter a second methanol pump (29) for pressurizing, enter a third circulator (30) for circulation, and are then pumped into the top of a first absorption tower (4);
the material flow coming out of the top of the first absorption tower (4) enters a first heat exchanger (3) to exchange heat with the raw material natural gas (1) sufficiently, and purified gas is conveyed out through a dehydrated natural gas collecting pipeline (31) after heat exchange;
the material flow coming out of the bottom of the first absorption tower (4) enters a throttle valve (5) for throttling, the material flow coming out of the throttle valve (5) enters a second heat exchanger (6) for heat exchange, and the material flow coming out enters a second separator (7) for secondary separation, and enters a second absorption tower (9) after separation; the supplemented methanol enters the top of the second absorption tower (9) through the first methanol inlet (8); after being fully absorbed by countercurrent contact in a second absorption tower (9), a material flow coming out of the tower bottom enters a first distributor (14) and is divided into two parts, one material flow enters a heater (13) for heating, and the heated material flow enters the bottom of the second absorption tower (9) through a first circulator (15); the other stream enters a second distributor (16) and is divided into two streams, one stream enters a molecular sieve dryer (17) for drying, the dried stream is mixed with the stream from the second distributor (16) and enters a second mixer (18) for secondary mixing, the mixed stream enters a second heat exchanger (6) for heat exchange, and the stream after heat exchange enters a third mixer (27);
the material flow coming out from the top of the second absorption tower (9) enters a third separator (10) for third separation, and the gas-phase material flow at the top of the third separator (10) is mixed with the gas-phase material flow coming out from the top of the second separator (7) in a first mixer (11); the mixed material flow enters the bottom of a water washing tower (12); the material flowing water enters the top of the water washing tower (12) through a water inlet (33) at the upper part of the water washing tower (12); the two streams are reversely contacted and fully absorbed; the material flow from the top of the water scrubber (12) is discharged through a water scrubber discharge outlet (36); the material flow coming out of the bottom of the water washing tower (12) enters a third heat exchanger (19) for full heat exchange, and the material flow coming out enters the middle part of a dehydrating tower (22); the temperature of the dehydration tower (22) is controlled to be 98-102 ℃ and the pressure is controlled to be 0.10-0.12MPa; the material flow coming out from the bottom of the dehydrating tower (22) enters a third heat exchanger (19) for heat exchange, and the discharged material flow is discharged through a third heat exchanger discharge outlet (35);
the material flow coming out from the top of the dehydrating tower (22) firstly enters a first cooler (21) for cooling, then enters a fourth separator (25) for separating gas phase, the separated liquid methanol is pressurized by a first methanol pump (26), and the pressurized material flow enters a third distributor (24); a part of the material flow passes through a second circulator (20) to enter the top of a dehydration tower (22), and the other part of the material flow enters a third mixer (27);
the material flow coming out from the bottom of the dehydration tower (22) enters a reboiler (23), and the material flow coming out of the reboiler (23) enters a third heat exchanger (19) to provide heat for the material flow coming out from the bottom of the water scrubber (12);
three streams entering a mixer (27) are mixed, and the mixed streams enter
Cooled in a second cooler (28) and then enters a second methanol pump (29) for pressurization,
after being pressurized, the waste water enters a third circulator (30) and is circularly pumped into a first absorption tower (4).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711491309.5A CN107916151B (en) | 2017-12-30 | 2017-12-30 | Dehydration system and method for natural gas |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711491309.5A CN107916151B (en) | 2017-12-30 | 2017-12-30 | Dehydration system and method for natural gas |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN107916151A CN107916151A (en) | 2018-04-17 |
| CN107916151B true CN107916151B (en) | 2023-10-20 |
Family
ID=61894627
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201711491309.5A Active CN107916151B (en) | 2017-12-30 | 2017-12-30 | Dehydration system and method for natural gas |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107916151B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115046422A (en) * | 2022-07-11 | 2022-09-13 | 西安石油大学 | Dew point corrosion prevention and control method for precooling heat exchanger of mixed refrigerant liquefaction system |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5782958A (en) * | 1995-12-28 | 1998-07-21 | Institut Francais Du Petrole | Process for the dehydration, deacidification and stripping of a natural gas, utilizing a mixture of solvents |
| CN101037629A (en) * | 2007-04-24 | 2007-09-19 | 胜利油田胜利工程设计咨询有限责任公司 | Natural gas ultrasonic dehydration method |
| CN102643694A (en) * | 2012-04-27 | 2012-08-22 | 新地能源工程技术有限公司 | Technique and device for drying and liquefaction of natural gas |
| CN103071475A (en) * | 2013-01-09 | 2013-05-01 | 西南石油大学 | Natural gas absorbent regeneration and energy conservation technology and device |
| CN204569865U (en) * | 2015-04-27 | 2015-08-19 | 中国五环工程有限公司 | Single stage method coal synthetic natural gas system |
| CN205011723U (en) * | 2015-09-25 | 2016-02-03 | 新地能源工程技术有限公司 | Rely on device of low temperature methanol solution desorption synthetic natural gas normal water |
| RU2613914C1 (en) * | 2015-12-11 | 2017-03-22 | Игорь Анатольевич Мнушкин | Method for processing natural hydrocarbon gas |
| RU2633563C1 (en) * | 2016-05-11 | 2017-10-13 | Общество с ограниченной ответственностью "Научно-исследовательский институт природных газов и газовых технологий - Газпром ВНИИГАЗ" | Plant for absorption preparation of natural gas |
| CN207775173U (en) * | 2017-12-30 | 2018-08-28 | 西安长庆科技工程有限责任公司 | A kind of dewatering system for natural gas |
-
2017
- 2017-12-30 CN CN201711491309.5A patent/CN107916151B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5782958A (en) * | 1995-12-28 | 1998-07-21 | Institut Francais Du Petrole | Process for the dehydration, deacidification and stripping of a natural gas, utilizing a mixture of solvents |
| CN101037629A (en) * | 2007-04-24 | 2007-09-19 | 胜利油田胜利工程设计咨询有限责任公司 | Natural gas ultrasonic dehydration method |
| CN102643694A (en) * | 2012-04-27 | 2012-08-22 | 新地能源工程技术有限公司 | Technique and device for drying and liquefaction of natural gas |
| CN103071475A (en) * | 2013-01-09 | 2013-05-01 | 西南石油大学 | Natural gas absorbent regeneration and energy conservation technology and device |
| CN204569865U (en) * | 2015-04-27 | 2015-08-19 | 中国五环工程有限公司 | Single stage method coal synthetic natural gas system |
| CN205011723U (en) * | 2015-09-25 | 2016-02-03 | 新地能源工程技术有限公司 | Rely on device of low temperature methanol solution desorption synthetic natural gas normal water |
| RU2613914C1 (en) * | 2015-12-11 | 2017-03-22 | Игорь Анатольевич Мнушкин | Method for processing natural hydrocarbon gas |
| RU2633563C1 (en) * | 2016-05-11 | 2017-10-13 | Общество с ограниченной ответственностью "Научно-исследовательский институт природных газов и газовых технологий - Газпром ВНИИГАЗ" | Plant for absorption preparation of natural gas |
| CN207775173U (en) * | 2017-12-30 | 2018-08-28 | 西安长庆科技工程有限责任公司 | A kind of dewatering system for natural gas |
Also Published As
| Publication number | Publication date |
|---|---|
| CN107916151A (en) | 2018-04-17 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US8876954B2 (en) | Natural gas dehydration unit with continuously fired reboiler | |
| US11287183B2 (en) | Method and plant for the purification of carbon dioxide using liquid carbon dioxide | |
| RU2605978C2 (en) | Method and device for extracting gas from gas mixture using venturi ejector | |
| CN105013296B (en) | A kind of selexol process decarbonization system and method for coupling acid gas concentrate | |
| CN102643694B (en) | Technique and device for drying and liquefaction of natural gas | |
| JP5036183B2 (en) | Improved solvent use and regeneration | |
| US11596897B2 (en) | Method for recovering CO2 in the Rectisol process and recovery system | |
| CN105664671B (en) | A kind of zero carbon emission technique gas purifying method and device | |
| EP3386609B1 (en) | Process and system for the purification of a gas | |
| CN106311149A (en) | Absorbent used for natural gas decarburization | |
| CN107916151B (en) | Dehydration system and method for natural gas | |
| CN106268191B (en) | A kind of low-temperature methanol washing tail-gas water washing device and its process | |
| CN202595073U (en) | Natural gas drying and liquefying device | |
| US20140275691A1 (en) | System and Method for H2S Removal Integrated with Stinson Process CO2 Removal | |
| CN103695043A (en) | Method for drying, purifying and cooling conversion rough synthesized gas and SNG product gas through low-temperature methanol washing and device thereof | |
| US9695373B2 (en) | System and method for natural gas dehydration | |
| CN210855897U (en) | For high content of CO2Ethane gas deep purification device | |
| CN104667709A (en) | Natural gas decarbonization treatment system | |
| CN210645772U (en) | Produce acid gas purifier of multiple purity hydrogen sulfide | |
| CN207775173U (en) | A kind of dewatering system for natural gas | |
| CN209917566U (en) | Polyolefin exhaust gas recovery device | |
| CN1028011C (en) | 3-c hydrocarbon decarbonizing process and device thereof | |
| US10315154B2 (en) | Method for the recovery of carbon dioxide from an absorbent with reduced supply of stripping steam | |
| CN220736979U (en) | Carbon dioxide trapping and absorbing device suitable for flue gas discharged by natural gas boiler | |
| CN104557385B (en) | A kind of refinery's mixing dry gas recovery system and recovery method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |