CN109320393B - A kind of associated gas ethane recovery methods - Google Patents
A kind of associated gas ethane recovery methods Download PDFInfo
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- CN109320393B CN109320393B CN201811354807.XA CN201811354807A CN109320393B CN 109320393 B CN109320393 B CN 109320393B CN 201811354807 A CN201811354807 A CN 201811354807A CN 109320393 B CN109320393 B CN 109320393B
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- C07—ORGANIC CHEMISTRY
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- C07C7/00—Purification; Separation; Use of additives
- C07C7/005—Processes comprising at least two steps in series
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
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Abstract
The invention discloses a kind of associated gas ethane recovery methods, the method unstripped gas isolates gas phase and liquid phase in cold catch pot pre-cooling through heat exchange cooling, it is subcooled using cold catch pot partial gas phase as demethanizer top material inlet, supercooling is mixed with a small amount of cold catch pot gas phase using cold catch pot Partial Liquid Phase hydrocarbon to feed as domethanizing column middle and upper part, reduce tower top temperature, improve ethane recovery, carbon dioxide solid is inhibited to be formed, the efficient plate-fin heat exchanger that cold heat exchanger uses multiply is pre-chilled and crossed in process, the refrigeration process mutually tied using expander refrigeration with cryogen refrigeration, form a kind of associated gas ethane recovery methods.The method improves ethane recovery, effectively inhibits the formation of carbon dioxide solid, is suitable for the associated gas ethane recovery device of outer defeated pressure lower (being less than 2.0MPa).
Description
Technical field
The present invention relates to natural gas processing technology field more particularly to a kind of associated gas ethane recovery methods.
Background technique
The associated gas makings of each elephant output is rich, containing the lime sets component such as more ethane, propane, butane, leads to
Cross recycling ethane and the above heavy constituent, can be improved the comprehensive utilization ratio of petroleum resources, promote China's ethylene raw lighting and
High quality realizes the maximization of the full industrial chain benefit of oil and gas development upstream and downstream.
Currently, China's associated gas ethane recovery, mainly based on undercooling process flow, refrigeration process is using swollen
The refrigeration process that swollen mechanism cold is combined with propane refrigeration, treatment scale are small by (most of 200 × 104m3/ d), defeated pressure outside natural gas
Power is low (being less than 2.0MPa), and existing main problem is that ethane recovery process is single, and ethane recovery is low (being lower than 85%), raw material
Carbon dioxide content is higher (part associated gas content is greater than 2%) in gas, and control carbon dioxide solid forms difficulty, system
Energy consumption height etc..
Existing typical case's ethane recovery flow chart is as shown in figure 3, its process is that unstripped gas enters expansion unit after pressurization is dehydrated
Pressurized end (K31) pressurization, then enter air cooler (A31) heat exchange cooling, enter back into feed gas separator (V31) and divided
From into the bottom domethanizing column (T31) after the liquid phase decompression cooling isolated；Its gas phase isolated is changed through unstripped gas pre-cooling
Enter cold catch pot (V32) after hot device (E31) heat exchange cooling, the gas phase that cold catch pot (V32) is isolated all flows through swollen
The middle and upper part of domethanizing column (T31) is sent into after expanding end (K32) the decompression cooling of swollen unit.Cold catch pot (V32) is isolated
Liquid phase be divided into two-way: all the way liquid phase first pass through cold heat exchanger (E32) heat exchange cooling supercooling after decompression enter domethanizing column (T31)
Top；Another way liquid phase enters the lower part domethanizing column (T31) after decompression cooling.
Its flow characteristics, which is to be subcooled using cold catch pot (V32) Partial Liquid Phase, provides reflux for demethanation tower top, leads to
It crosses raising cold catch pot (V32) Partial Liquid Phase and crosses cooling capacity, ethane recovery can be improved, but tower top supercooled liquid phase composition is richer,
85% or so, this process raising ethane recovery will cause ethane recovery apparatus system energy consumption and is substantially increased ethane recovery.
In order to overcome the shortcomings of above-mentioned undercooling ethane recovery process (Fig. 3), (it is less than for raw gas pressure is low
0.5MPa), outer distribution pressure low (being less than 2.0MPa), treatment scale are small by (most of 200 × 104m3/ d) associated gas, this
Invention develops a kind of associated gas ethane recovery methods, recycles the lime set in associated gas more than ethane and ethane, mentions
High ethane recovery (rate of recovery is greater than 90%), effectively improve the economy and social benefit of oil field development.
Summary of the invention
Gas phase supercooling is mutually subcooled with gas-liquid mixed and combines by the present invention, proposes a kind of associated gas ethane recovery side
Method, this method effectively improves ethane recovery to 90% or more, while carbon dioxide solid being inhibited to be formed, ethane recovery
Device economic benefit has obtained effective promotion.
A kind of associated gas ethane recovery methods proposed by the present invention enter expanding machine group after unstripped gas pressurization dehydration
Pressurized end pressurization then enters air cooler heat exchange cooling, enters back into feed gas separator and separated, the gas phase warp isolated
Enter cold catch pot after the heat exchange cooling of unstripped gas precool heat exchanger device, the liquid phase isolated is through entering sewage treatment unit.Low temperature
The gas phase that separator is isolated divides two-way: 90%~95% gas phase is by cold heat exchanger heat exchange cooling supercooling in first via gas phase
Decompression enters demethanizer overhead afterwards；Enter in domethanizing column after the expanding end decompression cooling of the second expanded unit of tunnel gas phase
Portion.The liquid phase that cold catch pot is isolated divides two-way: mixing cold catch pot in first via liquid phase and isolates in first via gas phase
5%~10% gas phase, decompression enters domethanizing column middle and upper part after cold heat exchanger exchanges heat cooling supercooling；Second tunnel liquid phase warp
Enter domethanizing column middle and lower part after decompression cooling.The gas phase that demethanizer overhead comes out successively passes through cold heat exchanger and unstripped gas is pre-
It is outer defeated after cold heat exchanger heat exchange heating.
Further technical solution is that the gas phase of the cold catch pot is divided into two-way: in first via gas phase 90%~
95% is depressured after cold heat exchanger exchanges heat cooling supercooling into demethanizer overhead；The expanded machine expansion arc drop of second tunnel gas phase
Enter domethanizing column middle and upper part after pressure drop temperature.
Further technical solution is that the first via gas phase flow rate that the cold catch pot is isolated accounts for cold catch pot
V12 isolates the 15%~35% of gas phase flow rate.
Further technical solution is that the liquid phase that the cold catch pot is isolated is divided into two-way: the incorporation of first via liquid phase
Cold catch pot isolates 5%~10% in first via gas phase, and exchanging heat to be depressured after cooling is subcooled using cold heat exchanger enters
Domethanizing column middle and upper part, is subcooled using mixed phase, be can get bigger temperature drop after being depressured, is improved ethane recovery；Second
Road liquid phase enters domethanizing column lower part after decompression cooling.
Further technical solution is that the flow for the first via liquid phase that the cold catch pot is isolated accounts for cold catch pot
V12 isolates the 60%~95% of liquid phase flow, CO in specific additional amount and unstripped gas2Content and ethane recovery are related, can
It is calculated by flowsheeting.
Further technical solution is that the unstripped gas precool heat exchanger device, excessively cold heat exchanger are all made of multiply plate-fin and change
Hot device, by one hot-fluid and four bursts of cold flows, two strands of hot-fluids are integrated in unstripped gas precool heat exchanger device with one cold flow respectively, supercooling is changed
In hot device.
Further technical solution is that one hot-fluid in the unstripped gas precool heat exchanger device is unstripped gas, four bursts of cold flows
Are as follows: the discharging of one demethanation top gaseous phase, two strands of domethanizing column lateral line withdrawal functions, one additional cryogen.Cross two in cold heat exchanger
Stock hot-fluid are as follows: the mixed phase of one cold catch pot partial gas phase, one cold catch pot a small amount of gas phase and Partial Liquid Phase；One
Cold flow is the discharging of demethanation top gaseous phase.
The liquid hydrocarbon that demethanizer bottom is fractionated is the lime set containing ethane and the above heavy constituent of ethane, according to product variety
Cutting is further distilled with quality requirement is separated into required product.If carbon dioxide content is exceeded in ethane product, need to be arranged de-
Carbon device.
Unstripped gas working condition of the present invention: unstripped gas is associated gas, and defeated pressure is low (being less than 2.0MPa) outside natural gas.
For pressurization refrigeration for main cold source, cryogen refrigeration is auxiliary cold source, can to specific ethane recovery engineering before the present invention uses expansion unit
Different cryogen systems is chosen according to carbon dioxide content, ethane recovery target value in raw gas pressure and composition, unstripped gas
It is cold.
The beneficial effects of the present invention are:
The present invention is a kind of associated gas ethane recovery methods, and compared with prior art, the present invention makes full use of gas phase
Supercooling, gas-liquid mixed is mutually subcooled reduces tower top temperature, and ethane recovery is up to 90% or more；Cold catch pot is made full use of to go out
Propane and the above heavy constituent improve domethanizing column top titanium dioxide as carbon dioxide solid formation inhibitor in the liquid phase come
Carbon frozen block allowance；Unstripped gas heat source is made full use of, multiple side reboilers are set, using efficient multiply plate-fin heat exchanger, is mentioned
High cold and hot utilization rate, reduces ethane recovery apparatus system energy consumption；Using refrigeration process is pressurized before expanding machine, simplifies ethane and return
Receive process.
Detailed description of the invention
Fig. 1 is one process flow chart of technical solution of the present invention；
Shown in Fig. 1: it is pre- that K11- expands unit pressurized end, A11- air cooler, V11- feed gas separator, E11- unstripped gas
It is de- that cold heat exchanger, V12- cold catch pot, E12- cross cold heat exchanger, K12- expansion unit expanding end, T11- domethanizing column, E13-
Methane bottom reboiler
Fig. 2 is two process flow chart of technical solution of the present invention；
Shown in Fig. 2: it is pre- that K21- expands unit pressurized end, A21- air cooler, V21- feed gas separator, E21- unstripped gas
Cold heat exchanger I, V22- cold catch pot I, E22- unstripped gas precool heat exchanger device II, E23- cross cold heat exchanger, V23- cryogenic separation
Device II, K22- expand unit expanding end, T21- domethanizing column
Fig. 3 is existing typical undercooling ethane recovery process flow chart；
Shown in Fig. 3: E31- unstripped gas precool heat exchanger device, E32- cross cold heat exchanger, V31- cold catch pot, K31- expansion
Unit pressurized end, K32- expand unit compression end, A31- air cooler, T31- domethanizing column
Fig. 4 is the process flow chart of present example 1.
Shown in Fig. 4: it is pre- that K41- expands unit pressurized end, A41- air cooler, V41- feed gas separator, E41- unstripped gas
It is de- that cold heat exchanger, V42- cold catch pot, E42- cross cold heat exchanger, K42- expansion unit expanding end, T41- domethanizing column, E43-
Ethane tower feed exchanger, P41- demethanizer bottoms pump, T42- dethanizer, E44- cooler, V43- deethanizer reflux tank,
P42- deethanizer reflux pump, E45- deethanization bottom reboiler.
Fig. 5 is the process flow chart of present example 2.
Shown in Fig. 5: it is pre- that K51- expands unit pressurized end, A51- air cooler, V51- feed gas separator, E51- unstripped gas
Cold heat exchanger, V52- cold catch pot I, E52- cross cold heat exchanger, the charging heat exchange of V53- cold catch pot II, E54- dethanizer
Device, K52- expansion unit expanding end, T51- domethanizing column, P51- demethanizer bottoms pump, E55- cooler, T52- dethanizer,
V54- deethanizer reflux tank, P52- deethanizer reflux pump, E56- deethanization bottom reboiler.
Specific embodiment
The present invention will be further explained below with reference to the attached drawings:
A kind of associated gas ethane recovery methods proposed by the present invention, technical solution are as shown in Figure 1.It is characterized in that
The pressurized end (K11) for entering expanding machine group after unstripped gas pressurization dehydration is pressurized, and then enters air cooler (A11) heat exchange cooling, then
It is separated in into feed gas separator (V11), the gas phase isolated is after unstripped gas precool heat exchanger device (E11) heat exchange cooling
Into cold catch pot (V12), the liquid phase isolated is through entering sewage treatment unit.The gas that cold catch pot (V12) is isolated
Phase divides two-way: 90%~95% gas phase is depressured after cold heat exchanger (E12) exchanges heat cooling supercooling and enters in first via gas phase
At the top of domethanizing column (T11)；Enter domethanizing column after the expanding end decompression cooling of the second expanded unit of tunnel gas phase (K12)
(T11) middle and upper part.The liquid phase that cold catch pot (V12) is isolated divides two-way: mixing cold catch pot (V12) in first via liquid phase
The gas phase for isolating in first via gas phase 5%~10%, decompression enters piptonychia after cold heat exchanger (E12) exchanges heat cooling supercooling
The middle and upper part alkane tower (T11)；Second tunnel liquid phase enters the middle and lower part domethanizing column (T11) after decompression cooling.Domethanizing column (T11) top
The gas phase that portion comes out is successively outer defeated after cold heat exchanger (E12) and unstripped gas precool heat exchanger device (E11) heat exchange heating.
Further technical solution is that the gas phase of the cold catch pot (V12) is divided into two-way: in first via gas phase
90%~95% is depressured after cold heat exchanger (E12) exchanges heat cooling supercooling at the top of domethanizing column (T11)；Second tunnel gas phase
Enter the middle and upper part domethanizing column (T11) after expanded machine (K12) expansion arc decompression cooling.
Further technical solution is that the first via gas phase flow rate that the cold catch pot (V12) is isolated accounts for low temperature point
The 10%~30% of gas phase flow rate is isolated from device V12.
Further technical solution is that the liquid phase that the cold catch pot (V12) is isolated is divided into two-way: first via liquid phase
5%~10% in first via gas phase is isolated in incorporation cold catch pot (V12), is exchanged heat and is cooled down using cold heat exchanger (E12)
Decompression enters the middle and upper part domethanizing column (T11) after supercooling, is subcooled using mixed phase, can get bigger temperature drop after being depressured, mentions
High ethane recovery；Second tunnel liquid phase enters the lower part domethanizing column (T11) after decompression cooling.
Further technical solution is that the flow for the first via liquid phase that the cold catch pot (V12) is isolated accounts for low temperature
Separator V12 isolates the 60%~95% of liquid phase flow, CO in specific additional amount and unstripped gas2Content and ethane recovery phase
It closes, can be calculated by flowsheeting.
Further technical solution is that the unstripped gas precool heat exchanger device (E11), excessively cold heat exchanger (E12) are all made of more
Stock plate-fin heat exchanger, by one hot-fluid and four bursts of cold flows, two strands of hot-fluids are integrated in unstripped gas pre-cooling with one cold flow respectively and change
Hot device (E11) is crossed in cold heat exchanger (E12).
Further technical solution is, one hot-fluid in the unstripped gas precool heat exchanger device (E11) is unstripped gas, four strands
Cold flow are as follows: the discharging of one demethanation top gaseous phase, two strands of domethanizing column lateral line withdrawal functions, one additional cryogen.Cross cold heat exchanger
(E12) two strands of hot-fluids in are as follows: one cold catch pot partial gas phase, a small amount of gas phase of one cold catch pot and Partial Liquid Phase
Mixed phase；One cold flow is the discharging of demethanation top gaseous phase.
The liquid hydrocarbon that demethanizer bottom is fractionated is the lime set containing ethane and the above heavy constituent of ethane, according to product variety
Cutting is further distilled with quality requirement is separated into required product.If carbon dioxide content is exceeded in ethane product, need to be arranged de-
Carbon device.
Unstripped gas working condition of the present invention: unstripped gas is associated gas, and defeated pressure is low (being less than 2.0MPa) outside natural gas.
For pressurization refrigeration for main cold source, cryogen refrigeration is auxiliary cold source, can to specific ethane recovery engineering before the present invention uses expansion unit
Different cryogen systems is chosen according to carbon dioxide content, ethane recovery target value in raw gas pressure and composition, unstripped gas
It is cold.
Embodiment one
As shown in Fig. 4, unstripped gas makings composition and calculating basic data are as follows for the embodiment of the present invention 1:
Unstripped gas treatment scale: 60 × 104m3/d
Raw gas pressure: 0.3MPa
Inlet temperature: 30 DEG C
Defeated pressure outside dry gas :≤2MPa
Defeated pressure outside ethane product: >=2MPa
Compressor adiabatic efficiency: 75% (including outer defeated compressor, refrigeration compressor, expansion unit pressurized end)
Expansion unit expanding end isentropic efficiency: 85%
Unstripped gas composition is shown in Table 1.
1 unstripped gas of table composition
| Component | N2 | CO2 | C1 | C2 | C3 | iC4 |
| Mol% | 0.1479 | 1.0 | 80.9669 | 9.1491 | 4.2788 | 0.769 |
| Component | nC4 | iC5 | nC5 | C6 | C7 | H2O |
| Mol% | 1.3408 | 0.0296 | 0.4141 | 0.3746 | 0.1193 | 1.4099 |
A kind of associated gas ethane recovery example one, process flow as shown in figure 4, unstripped gas is pressurized to 4.5MPa,
Through air-cooled water-cooled cooling to 40 DEG C, into molecular sieve dehydration device after into expanding machine group K41 pressurized end pressurization after gas phase
(5.4MPa, 56.3 DEG C), then enter feed gas separator V41 (5.34MPa, 40 DEG C) after water cooled cooling, feed gas separator
The liquid phase that V41 is isolated enters the bottom domethanizing column T41；The gas phase that feed gas separator V41 is isolated is changed through unstripped gas pre-cooling
Enter cold catch pot V42, the gas phase that cold catch pot V42 (5.28MPa, -41 DEG C) is isolated point after hot device E41 heat exchange cooling
Two-way: 89% (its flow accounts for 32.5% that cold catch pot V42 isolates gas phase flow rate) in first via gas phase is changed through supercooling
Decompression (1.9MPa, -105 DEG C) enters at the top of domethanizing column T41 after hot device E42 heat exchange cooling supercooling, cold catch pot V42 separation
(1.9MPa, -81.1 DEG C) enters domethanizing column T41 after the expanding end decompression cooling of the expanded unit K42 of the second tunnel gas phase out
Middle and upper part.
The liquid phase that cold catch pot V42 is isolated divides two-way, and (its flow accounts for cold catch pot V42 and isolates liquid phase all the way
The 90% of liquid phase flow) in 11% cooling down through cold heat exchanger E42 of isolating in first via gas phase of incorporation cold catch pot V42
Decompression (1.9MPa, -91.2 DEG C) enters the top domethanizing column T41 after cold；Another way liquid phase through decompression cooling after (1.95MPa ,-
63.21 DEG C) enter the middle and lower part domethanizing column T41.
The gas phase come out at the top of domethanizing column T41 successively passes through cold heat exchanger E42 and unstripped gas precool heat exchanger device E41 heat exchange
(1.76MPa, 32.8 DEG C) enters defeated outside outer defeated natural gas line afterwards after heating, and the flow of outer gas transmission is 49.73 × 104m3/d。
From the middle and lower part domethanizing column T41 extract out two bursts of low temperature liquid phases of different potential temperatures (- 78 DEG C, -54.9 DEG C) respectively with mistake
Domethanizing column T41 is flowed into after cold heat exchanger E42, unstripped gas forecooler E41 heat exchange heating, as side reboiler heat source；It takes out bottom
One low temperature position (- 6.0 DEG C) liquid phase and unstripped gas forecooler E41, which exchange heat, out provides heat source, propane refrigeration system point for reboiler
Not providing -37 DEG C for unstripped gas forecooler E41, (cooling capacity is 463.7kW), deethanization tower top cooler E44 provides -15 DEG C of temperature
Position (cooling capacity 335.4kW), the shaft power of propane refrigeration system are 356.8kW.
The liquid hydrocarbon (1.9MPa, 7.3 DEG C) that the bottom domethanizing column T41 is fractionated is pumped through domethanizing column tower bottom reflux pump P41
It is 9043.1kg/h high-pressure liquid propane through dethanizer feed exchanger E43 and mass flow after being pressurized to 2.6MPa
(1.78MPa, 50 DEG C) heat exchange is warming up to 30 DEG C and enters in the middle part of dethanizer, the gas phase that dethanizer T42 tower top is fractionated
(2.4MPa, -2.9 DEG C) is divided into two-way: first via gas phase (its flow account for top gaseous phase total flow 46%) through dethanizer into
Material heat exchanger E43 heat exchange enters decarbonization device after being warming up to 30 DEG C, and ethane product amount is 2814.3kg/h after decarbonization device, the
Two tunnels enter deethanizer reflux tank V43, the liquid phase that return tank is separated after cooler E44 is cooled to -10 DEG C
(2.38MPa, -10 DEG C) is flowed back at the top of dethanizer T42 after deethanizer reflux pump P42 boosting.
The liquid (2.45MPa, 90 DEG C) that the bottom dethanizer T42 is fractionated is solidifying containing propane and the above heavy constituent of propane
Liquid (molar content of its ethane is 1%), the yield of lime set is 4052.5kg/h.According to product variety and quality requirement into one
Step distillation cutting is separated into required product.The wherein CO of domethanizing column T412Minimum frozen block allowance is 5.01 DEG C, ethane recovery dress
The ethane recovery set is 94.89%.
This Examples Simulation Results shows: under identical working condition, this example and existing undercooling ethane recovery process
Figure (Fig. 3) is compared, and ethane recovery improves 9.39%, and ethane product amount increases 6.81t/d, system compresses function (raw material
The sum of gas work done during compression and propane refrigeration work done during compression) 7kW is increased only, ethane recovery greatly improves, effective lifting device economy
Benefit.
Carbon dioxide content in unstripped gas is only become 1.5% in examples detailed above one, under identical working condition, by piptonychia
The CO of alkane tower T412In the case where 5 DEG C, analog result is shown: ethane recovery 93% for minimum frozen block allowance control, with
Carbon dioxide content raising ethane recovery only declines 1.89% in unstripped gas, shows that the present invention contains carbon dioxide in unstripped gas
Amount has good adaptability.
Embodiment two
As shown in Fig. 5, unstripped gas makings composition and calculating basic data are as follows for the embodiment of the present invention 2:
Unstripped gas treatment scale: 60 × 104m3/d
Raw gas pressure: 0.3MPa
Inlet temperature: 30 DEG C
Defeated pressure outside dry gas :≤2MPa
Defeated pressure outside ethane product: >=2MPa
Compressor adiabatic efficiency: 75% (including outer defeated compressor, refrigeration compressor, expansion unit pressurized end)
Expansion unit expanding end isentropic efficiency: 85%
Unstripped gas composition is shown in Table 2.
2 unstripped gas of table composition
| Component | N2 | CO2 | C1 | C2 | C3 | iC4 |
| Mol% | 0.1479 | 1.0 | 80.9669 | 9.1491 | 4.2788 | 0.769 |
| Component | nC4 | iC5 | nC5 | C6 | C7 | H2O |
| Mol% | 1.3408 | 0.0296 | 0.4141 | 0.3746 | 0.1193 | 1.4099 |
A kind of associated gas ethane recovery example two, process flow as shown in figure 5, unstripped gas is pressurized to 4.5MPa,
Through air-cooled water-cooled cooling to 40 DEG C, after entering back into the pressurized end pressurization for entering expanding machine group K51 after molecular sieve dehydration device is dehydrated
Gas phase (5.4MPa, 56.8 DEG C), then enter feed gas separator V51 (5.37MPa, 40 DEG C) after water cooled cooling, unstripped gas point
Enter cold catch pot V52, unstripped gas point after unstripped gas precool heat exchanger device E51 heat exchange cooling from the gas phase that device V51 is isolated
Enter sewage disposal system from the device V51 liquid phase isolated.Liquid phase (5.34MPa, -1 DEG C) warp that cold catch pot V52 is isolated
Enter the middle and lower part domethanizing column T51 after decompression cooling.
The gas phase that cold catch pot V52 (5.34MPa, -1 DEG C) is isolated is by unstripped gas precool heat exchanger device E52 heat exchange drop
Enter cold catch pot V53 after temperature, the gas phase that cold catch pot V53 (5.31MPa, -41 DEG C) is isolated divides two-way: first via gas
89.2% gas phase (its flow accounts for 32.2% that cold catch pot V53 isolates gas phase flow rate) lease making crosses cold heat exchanger in phase
Pressure regulation supercooling (1.9MPa, -105 DEG C) enters at the top of domethanizing column T51 after E52 heat exchange cooling, and cold catch pot V53 is isolated
The expanding end of second tunnel gas phase (its flow accounts for 67.5% that cold catch pot V52 isolates gas phase flow rate) expanded unit K52
(1.9MPa, -80.4 DEG C) enters the middle and upper part domethanizing column T51 after decompression cooling.
The liquid phase that cold catch pot V53 is isolated divides two-way: (its flow accounts for cold catch pot V53 separation to first via liquid phase
The 94% of liquid phase flow out) incorporation cold catch pot V53 isolate in first via gas phase it is 10.8% few with cold catch pot V53
Measure gas phase mixing through cold heat exchanger E53 cooling supercooling after decompression (1.9MPa,
- 92.3 DEG C) enter the top domethanizing column T51；(its flow accounts for cold catch pot V53 and isolates liquid second tunnel liquid phase
The 6% of phase flow rate) through decompression cooling after (1.95MPa, -64.99 DEG C) enter the middle and lower part domethanizing column T51.
The gas phase come out at the top of domethanizing column T51 successively passes through cold heat exchanger E53, unstripped gas precool heat exchanger device E52, raw material
(1.76MPa, 36 DEG C) enters defeated, the stream of outer gas transmission outside outer defeated natural gas line afterwards after gas precool heat exchanger device E51 heat exchange heating
Amount is 49.79 × 104m3/d。
From the middle and lower part domethanizing column T51 extract out two bursts of low temperature liquid phases of different potential temperatures (- 73.5 DEG C, -47.8 DEG C) respectively with
Domethanizing column T51 is flowed into after cold heat exchanger E53, unstripped gas forecooler E52 heat exchange heating is subcooled, as side reboiler heat source；Bottom
It extracts one low temperature position (- 4.8 DEG C) liquid phase and unstripped gas forecooler E51 heat exchange out and provides heat source, propane refrigeration system for reboiler in portion
System is respectively that unstripped gas forecooler E52 offer -37 DEG C of (cooling capacity is 422.5kW), deethanization tower top cooler E55 provide -15 DEG C
Potential temperature (cooling capacity 331.1kW), the shaft power of propane refrigeration system is 333.9kW.
The liquid hydrocarbon (1.9MPa, 7.6 DEG C) that the bottom domethanizing column T51 is fractionated is pumped through domethanizing column tower bottom reflux pump P51
It is 8525.1kg/h high-pressure liquid propane through dethanizer feed exchanger E54 and mass flow after being pressurized to 2.6MPa
(1.78MPa, 50 DEG C) heat exchange is warming up to 30 DEG C and enters in the middle part of dethanizer, the gas phase that dethanizer T52 is fractionated
(2.4MPa, -2.9 DEG C) is divided into two-way: first via gas phase (its flow account for top gaseous phase total flow 46%) through dethanizer into
Material heat exchanger E43 heat exchange enters decarbonization device after being warming up to 30 DEG C, and ethane product amount is 2788.6kg/h after decarbonization device, the
Two tunnel gas phases enter deethanizer reflux tank V54, the liquid that return tank is separated after cooler E55 is cooled to -10 DEG C
(2.38MPa, -10 DEG C) is flowed back at the top of dethanizer T52 after deethanizer reflux pump P52 boosting.
The liquid phase (2.45MPa, 90 DEG C) that the bottom dethanizer T52 is fractionated is containing propane and the above heavy constituent of propane
Lime set (molar content of its ethane is 1%), the yield of lime set is 4057.6kg/h.According to product variety and quality requirement into
The distillation cutting of one step is separated into required product.The wherein CO of domethanizing column T512Minimum frozen block allowance is 5.01 DEG C, ethane recovery
The ethane recovery of device is 94.2%.
This Examples Simulation Results shows: under identical working condition, this example and existing undercooling ethane recovery process
Figure (Fig. 3) is compared, and ethane recovery improves 8.71%, and ethane product amount increases 5.68t/d, system compresses function (raw material
The sum of gas work done during compression and propane refrigeration work done during compression) 16kW is reduced, ethane recovery greatly improves, effective lifting device economy effect
Benefit.
When unstripped gas is richer and carbon dioxide content is less (carbon dioxide molar content is less than or equal to 1%), in process
It needs to carry out unstripped gas two-stage pre-cooling, two-stage separation on the basis of Fig. 1, is additionally arranged a unstripped gas precool heat exchanger device and pre-cooling
Separator.Its flow chart is as shown in Fig. 2, the present invention is provided with unstripped gas precool heat exchanger device (E21), unstripped gas precool heat exchanger device
(E22) and separator (V21), pre-cooling separator (V22) is pre-chilled, two-stage pre-cooling, two-stage separation is realized, by unstripped gas pre-separation
Part heavy hydrocarbon out reduces unstripped gas and institute's chilling requirement is pre-chilled, reduces ethane recovery plant energy consumption.Process rest part and flow chart
1 is identical.
Basic principles and main features and advantages of the present invention of the invention have been shown and described above.The technology of the industry
Personnel are it should be appreciated that the present invention is not limited to the above embodiments, and the above embodiments and description only describe this
The principle of invention, without departing from the spirit and scope of the present invention, various changes and improvements may be made to the invention, these changes
Change and improvement all fall within the protetion scope of the claimed invention.The claimed scope of the invention by appended claims and its
Equivalent thereof.
Claims (5)
1. a kind of associated gas ethane recovery methods, it is characterised in that: the following steps are included: step 1: former after pressurization dehydration
Material gas enters pressurized end (K11) pressurization of expansion unit, then enters air cooler (A11) heat exchange cooling, enters back into unstripped gas point
From being separated in device (V11), the gas phase isolated enters cryogenic separation after unstripped gas precool heat exchanger device (E11) heat exchange cooling
Device (V12), the liquid phase isolated enter sewage treatment unit；Step 2: the gas phase that cold catch pot (V12) is isolated is divided to two
Road: 90%~95% gas phase in first via gas phase is depressured after cold heat exchanger (E12) exchanges heat cooling supercooling enters demethanation
At the top of tower (T11)；Enter in domethanizing column (T11) after the expanding end decompression cooling of the second expanded unit of tunnel gas phase (K12)
Portion；Step 3: the liquid phase that cold catch pot (V12) is isolated divides two-way: mixing in the first via liquid phase cold catch pot (V12) point
5%~10% gas phase in first via gas phase is separated out, decompression enters demethanation after cold heat exchanger (E12) exchanges heat cooling supercooling
The middle and upper part tower (T11)；Second tunnel liquid phase enters the middle and lower part domethanizing column (T11) after decompression cooling；Step 4: domethanizing column
(T11) gas phase that top comes out is successively outer after cold heat exchanger (E12) and unstripped gas precool heat exchanger device (E11) heat exchange heating
It is defeated.
2. a kind of associated gas ethane recovery methods according to claim 1, it is characterised in that: cold catch pot
(V12) first via gas phase flow rate isolated accounts for cold catch pot (V12) and isolates the 15%~35% of gas phase flow rate.
3. a kind of associated gas ethane recovery methods according to claim 1, it is characterised in that: cold catch pot
(V12) flow for the first via liquid phase isolated accounts for cold catch pot (V12) and isolates the 60%~95% of liquid phase flow, specifically
CO in additional amount and unstripped gas2Content and ethane recovery are related, can be calculated by flowsheeting.
4. a kind of associated gas ethane recovery methods according to claim 1, it is characterised in that: unstripped gas precool heat exchanger
Device (E11) crosses cold heat exchanger (E12) and is all made of multiply plate-fin heat exchanger, by one hot-fluid and four bursts of cold flows, two strands of hot-fluids and
One cold flow is integrated in unstripped gas precool heat exchanger device (E11) respectively, crosses in cold heat exchanger (E12).
5. a kind of associated gas ethane recovery methods according to claim 4, it is characterised in that: unstripped gas precool heat exchanger
One hot-fluid is unstripped gas, four bursts of cold flows in device (E11) are as follows: the discharging of one demethanation top gaseous phase, two strands of domethanizing column side lines
Two strands of hot-fluids of cold heat exchanger (E12) are crossed in extraction, one additional cryogen are as follows: one cold catch pot partial gas phase, one is low
The mixed phase of warm separator a small amount of gas phase and Partial Liquid Phase；One cold flow is the discharging of demethanation top gaseous phase.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105037069A (en) * | 2015-08-20 | 2015-11-11 | 西南石油大学 | Method for recovering ethane in high-pressure natural gases |
| CN106397087A (en) * | 2016-08-30 | 2017-02-15 | 西安长庆科技工程有限责任公司 | Method for recovering ethane, liquefied gas and natural gasoline from CO2-containing natural gas |
| CN108689794A (en) * | 2018-07-13 | 2018-10-23 | 中国石油工程建设有限公司 | The devices and methods therefor of ethane is recycled from natural gas |
| CN108731380A (en) * | 2018-06-11 | 2018-11-02 | 西南石油大学 | A kind of ethane recovery methods being suitable for rich gas with absorption tower |
| CN108759305A (en) * | 2018-06-11 | 2018-11-06 | 西南石油大学 | A kind of natural gas ethane recovery methods to flow back more |
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Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105037069A (en) * | 2015-08-20 | 2015-11-11 | 西南石油大学 | Method for recovering ethane in high-pressure natural gases |
| CN106397087A (en) * | 2016-08-30 | 2017-02-15 | 西安长庆科技工程有限责任公司 | Method for recovering ethane, liquefied gas and natural gasoline from CO2-containing natural gas |
| CN108731380A (en) * | 2018-06-11 | 2018-11-02 | 西南石油大学 | A kind of ethane recovery methods being suitable for rich gas with absorption tower |
| CN108759305A (en) * | 2018-06-11 | 2018-11-06 | 西南石油大学 | A kind of natural gas ethane recovery methods to flow back more |
| CN108689794A (en) * | 2018-07-13 | 2018-10-23 | 中国石油工程建设有限公司 | The devices and methods therefor of ethane is recycled from natural gas |
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