CN113355143A - Natural gas nitrogen and carbon dioxide removing method and device based on controllable-aperture molecular sieve - Google Patents
Natural gas nitrogen and carbon dioxide removing method and device based on controllable-aperture molecular sieve Download PDFInfo
- Publication number
- CN113355143A CN113355143A CN202110828746.1A CN202110828746A CN113355143A CN 113355143 A CN113355143 A CN 113355143A CN 202110828746 A CN202110828746 A CN 202110828746A CN 113355143 A CN113355143 A CN 113355143A
- Authority
- CN
- China
- Prior art keywords
- carbon dioxide
- natural gas
- molecular sieve
- nitrogen
- adsorption
- 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.)
- Pending
Links
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 title claims abstract description 190
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 title claims abstract description 126
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 title claims abstract description 91
- 239000003345 natural gas Substances 0.000 title claims abstract description 86
- 239000002808 molecular sieve Substances 0.000 title claims abstract description 71
- URGAHOPLAPQHLN-UHFFFAOYSA-N sodium aluminosilicate Chemical compound [Na+].[Al+3].[O-][Si]([O-])=O.[O-][Si]([O-])=O URGAHOPLAPQHLN-UHFFFAOYSA-N 0.000 title claims abstract description 70
- 239000001569 carbon dioxide Substances 0.000 title claims abstract description 63
- 229910002092 carbon dioxide Inorganic materials 0.000 title claims abstract description 63
- JCXJVPUVTGWSNB-UHFFFAOYSA-N nitrogen dioxide Inorganic materials O=[N]=O JCXJVPUVTGWSNB-UHFFFAOYSA-N 0.000 title claims abstract description 42
- 238000000034 method Methods 0.000 title claims abstract description 40
- 239000007789 gas Substances 0.000 claims abstract description 46
- 229910052757 nitrogen Inorganic materials 0.000 claims abstract description 24
- 239000002994 raw material Substances 0.000 claims abstract description 14
- 239000011148 porous material Substances 0.000 claims abstract description 8
- 238000001179 sorption measurement Methods 0.000 claims description 87
- 230000008569 process Effects 0.000 claims description 19
- GNKTZDSRQHMHLZ-UHFFFAOYSA-N [Si].[Si].[Si].[Ti].[Ti].[Ti].[Ti].[Ti] Chemical compound [Si].[Si].[Si].[Ti].[Ti].[Ti].[Ti].[Ti] GNKTZDSRQHMHLZ-UHFFFAOYSA-N 0.000 claims description 5
- 238000003795 desorption Methods 0.000 claims description 4
- 238000010926 purge Methods 0.000 claims description 2
- 239000003463 adsorbent Substances 0.000 abstract description 6
- 238000000746 purification Methods 0.000 abstract description 2
- 238000000926 separation method Methods 0.000 description 7
- 238000012856 packing Methods 0.000 description 6
- 230000008929 regeneration Effects 0.000 description 5
- 238000011069 regeneration method Methods 0.000 description 5
- 238000004458 analytical method Methods 0.000 description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 4
- 239000004215 Carbon black (E152) Substances 0.000 description 3
- 238000005265 energy consumption Methods 0.000 description 3
- 238000001914 filtration Methods 0.000 description 3
- 229930195733 hydrocarbon Natural products 0.000 description 3
- 150000002430 hydrocarbons Chemical class 0.000 description 3
- 239000012535 impurity Substances 0.000 description 3
- 239000012528 membrane Substances 0.000 description 3
- 239000003921 oil Substances 0.000 description 3
- 230000009471 action Effects 0.000 description 2
- 238000001816 cooling Methods 0.000 description 2
- 238000005034 decoration Methods 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 230000018109 developmental process Effects 0.000 description 2
- 229910001873 dinitrogen Inorganic materials 0.000 description 2
- 239000003949 liquefied natural gas Substances 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000010924 continuous production Methods 0.000 description 1
- 230000001276 controlling effect Effects 0.000 description 1
- 230000002596 correlated effect Effects 0.000 description 1
- 239000010779 crude oil Substances 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000006073 displacement reaction Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000011049 filling Methods 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- QJGQUHMNIGDVPM-UHFFFAOYSA-N nitrogen(.) Chemical compound [N] QJGQUHMNIGDVPM-UHFFFAOYSA-N 0.000 description 1
- 230000035515 penetration Effects 0.000 description 1
- 239000012466 permeate Substances 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
Images
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
-
- 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
- C10L3/102—Removal of contaminants of acid contaminants
- C10L3/104—Carbon dioxide
-
- 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
- C10L3/105—Removal of contaminants of nitrogen
-
- 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
- C10L2290/00—Fuel preparation or upgrading, processes or apparatus therefore, comprising specific process steps or apparatus units
- C10L2290/54—Specific separation steps for separating fractions, components or impurities during preparation or upgrading of a fuel
- C10L2290/542—Adsorption of impurities during preparation or upgrading of a fuel
Abstract
The invention provides a method and a device for removing nitrogen and carbon dioxide from natural gas based on a controllable-aperture molecular sieve, and relates to the technical field of natural gas purification. The invention provides a natural gas nitrogen and carbon dioxide removing method based on a controllable-aperture molecular sieve, which comprises the following steps of: adsorbing nitrogen and carbon dioxide in the raw material natural gas by using a molecular sieve to obtain purified natural gas; the pore diameter of the molecular sieve is more than 0.36nm and less than 0.38 nm. The invention adopts the molecular sieve with controllable aperture as the adsorbent, the aperture of the molecular sieve can adsorb gases such as nitrogen (0.36nm), carbon dioxide (0.33nm) and the like with smaller aperture, the molecular diameter of methane (0.38nm) is larger than the aperture of the molecular sieve, and methane is not adsorbed, thereby realizing the removal of nitrogen and carbon dioxide in natural gas.
Description
Technical Field
The invention relates to the technical field of natural gas purification, in particular to a method and a device for removing nitrogen and carbon dioxide from natural gas based on a controllable-aperture molecular sieve.
Background
With the continuous updating of oil and gas field development technology, nitrogen flooding is widely used as an effective oil displacement and yield increase method for oil field development, and produced associated gas contains nitrogen while the yield of crude oil is increased. Because contain nitrogen gas and make the associated gas calorific value reduce, high concentration contains nitrogen and can make even the natural gas can't burn, when the associated gas is as low reaches raw materials, can influence low reaches production, consequently need separate natural gas and nitrogen gas, reduce nitrogen content in the natural gas, improve natural gas calorific value and quality, realize the rational utilization of natural gas resource.
Conventional denitrification processes for natural gas include: (1) a single-temperature denitrification method is carried out along with a natural gas liquefaction process, nitrogen is flashed from Liquefied Natural Gas (LNG) to realize denitrification in the natural gas liquefaction process, however, the process needs to depend on natural gas liquefaction equipment and flow, and denitrification treatment is carried out by adopting a low-temperature separation method under the working condition that only the natural gas needs to be denitrified but not the natural gas liquefaction, and firstly, CO in incoming gas needs to be subjected to denitrification treatment2And water and other components are strictly required, and the subsequent cooling zone process can be carried out only by pretreatment, so that the method has the defects of complex process flow, high investment and high energy consumption. (2) The membrane separation denitrification method utilizes the difference principle that different gases permeate through a membrane to realize the separation of nitrogen and natural gas, has the characteristics of high reliability, long service life, small volume, low dew point of denitrified gas and the like, but has the problems of low membrane selectivity, small separation coefficient and the like, and is not mature at present. (3) The traditional pressure swing adsorption method adopts a large-aperture adsorbent to adsorb methane gas, takes nitrogen as permeating gas to realize the separation of methane and nitrogen, and has the defects of large adsorbent dosage, large adsorption tank volume and high equipment investment because methane accounts for the main proportion in natural gas; the nitrogen removal rate after separation is low, and the separation requirement can be met only by multistage series adsorption; the pressure of the separated methane gas is low, the subsequent flow needs further pressurization, and the equipment investment and the energy consumption are increased.
Disclosure of Invention
The invention aims to provide a method and a device for removing nitrogen and carbon dioxide from natural gas based on a molecular sieve with controllable aperture.
In order to achieve the above object, the present invention provides the following technical solutions:
the invention provides a natural gas nitrogen and carbon dioxide removing method based on a controllable-aperture molecular sieve, which comprises the following steps of:
adsorbing nitrogen and carbon dioxide in the raw material natural gas by using a molecular sieve to obtain purified natural gas; the pore diameter of the molecular sieve is more than 0.36nm and less than 0.38 nm.
Preferably, the pressure of adsorption is 0.3-1.0 MPa.
Preferably, the molar content of nitrogen in the raw natural gas is less than or equal to 15 percent; the molar content of the carbon dioxide is less than or equal to 10 percent.
Preferably, the adsorption capacity of the molecular sieve to nitrogen is 45-60 mL/g; the adsorption capacity of the molecular sieve to carbon dioxide is 10-15 mg/g.
Preferably, after said adsorption, a molecular sieve enriched in nitrogen and carbon dioxide is also obtained; and resolving the molecular sieve rich in nitrogen and carbon dioxide to obtain a mixed gas of nitrogen and carbon dioxide and a regenerated molecular sieve.
Preferably, the pressure for the analysis is-50 to-60 kPa.
Preferably, the molecular sieve is a titanium silicate molecular sieve.
The invention provides a natural gas nitrogen and carbon dioxide removal device based on the method of the technical scheme, which comprises the following steps: an adsorption tank; and the interior of the adsorption tank is filled with a molecular sieve.
Preferably, a vacuum pump is further included; and the air inlet of the vacuum pump is communicated with the air outlet of the adsorption tank.
Preferably, the device also comprises a purified gas buffer tank and a vacuum pump buffer tank; the gas inlet of the purified gas buffer tank is communicated with the discharge hole of the adsorption tank; and the air inlet of the vacuum pump buffer tank is communicated with the air outlet of the vacuum pump.
The invention provides a natural gas nitrogen and carbon dioxide removing method based on a controllable-aperture molecular sieve, which comprises the following steps of: adsorbing nitrogen and carbon dioxide in the raw material natural gas by using a molecular sieve to obtain purified natural gas; the pore diameter of the molecular sieve is more than 0.36nm and less than 0.38 nm. The invention adopts the molecular sieve with controllable aperture as the adsorbent, the aperture of the molecular sieve is more than 0.36nm and less than 0.38nm, the molecular sieve can adsorb nitrogen (0.36nm), carbon dioxide (0.33nm) and other gases with smaller aperture, the diameter of methane molecule (0.38nm) is more than the aperture of the molecular sieve, the invention can adsorb nitrogen, carbon dioxide and other impurity gases, methane is not adsorbed, and further the nitrogen and carbon dioxide in natural gas are removed. In the invention, the dosage of the molecular sieve is positively correlated with the content of the nitrogen, the carbon dioxide and other gases, and the ratio of the nitrogen to the carbon dioxide in the natural gas is less, so that the molecular sieve adsorbent has the advantages of small equipment volume and high nitrogen removal rate compared with the traditional pressure swing adsorption process. The pressure loss of the separated methane gas is small and less than 0.05MPa, the pressure of the raw material natural gas is effectively reserved, the pressurization is not needed, the flow is simplified, and the operation energy consumption is reduced. The method directly adsorbs the raw material natural gas to be removed, does not need to carry out low-temperature cooling on the natural gas, and has simple process flow. The example results show that the removal rate of the nitrogen in the natural gas is 52-72% and the removal rate of the carbon dioxide is 44-56% by adopting the method.
Drawings
FIG. 1 is a diagram of a natural gas nitrogen and carbon dioxide removal plant used in an embodiment of the present invention; the device comprises a separator 1, a first adsorption tank 2-1, a second adsorption tank 2-2, a third adsorption tank 2-3, a fourth adsorption tank 2-4, a molecular sieve 3, a purified gas buffer tank 4, a vacuum pump 5, a vacuum pump buffer tank 6, a switch valve 7 and a PLC control system 8.
Detailed Description
The invention provides a natural gas nitrogen and carbon dioxide removing method based on a controllable-aperture molecular sieve, which comprises the following steps of:
adsorbing nitrogen and carbon dioxide in the raw material natural gas by using a molecular sieve to obtain purified natural gas; the pore diameter of the molecular sieve is more than 0.36nm and less than 0.38 nm.
In the present invention, the pore size of the molecular sieve is preferably 0.37 nm. In the present invention, the molecular sieve is preferably a titanium silicate molecular sieve. The invention has no special requirements on the preparation method of the titanium silicate molecular sieve, and the titanium silicate molecular sieve well known to the technical personnel in the field can be adopted. In the invention, the adsorption capacity of the molecular sieve to nitrogen is preferably 45-60 mL/g; the adsorption capacity of the molecular sieve for carbon dioxide is preferably 10-15 mg/g.
In the present invention, the molecular sieve is preferably spherical or columnar in appearance. The invention adopts the molecular sieve with proper aperture to realize the adsorption of nitrogen and carbon dioxide, thereby obtaining the purified natural gas.
In the invention, the molar content of nitrogen in the raw material natural gas is preferably less than or equal to 15%, and more preferably 6-12%. In the present invention, the molar content of carbon dioxide in the feed natural gas is preferably 10% or less, more preferably 5% or less.
In a particular embodiment of the invention, the gas content of the feed natural gas is preferably 100Nm3H; the temperature of the raw material natural gas is preferably 20-30 ℃.
In the invention, the adsorption pressure is preferably 0.3-1.0 MPa, and more preferably 0.6-1.0 MPa; the adsorption time is preferably 5-15 min, and more preferably 5-10 min.
In the invention, the molar content of nitrogen in the purified natural gas is preferably 2.6-4.8%, and more preferably 2.9-4.6%; the mole content of carbon dioxide in the purified natural gas is preferably 2.2-2.8%, and more preferably 2.3-2.7%. The method can effectively remove nitrogen and carbon dioxide in the raw material natural gas.
In the present invention, after the adsorption, a molecular sieve rich in nitrogen and carbon dioxide is preferably also obtained. The molecular sieve rich in nitrogen and carbon dioxide is preferably analyzed to obtain the mixed gas of nitrogen and carbon dioxide and the regenerated molecular sieve. In the present invention, the pressure for the analysis is preferably-50 to-60 kPa, more preferably-55 kPa; the time for the analysis is preferably less than or equal to 10 min. The invention is based on the controllable aperture molecular sieve, adopts the pressure swing adsorption process to realize the adsorption of nitrogen and carbon dioxide under the pressure condition, and separates out the nitrogen and carbon dioxide under the negative pressure condition, thereby realizing the regeneration and the repeated use of the molecular sieve.
The invention adopts the adsorption pressure and the desorption pressure to realize the absorption and regeneration process of the molecular sieve, natural gas is taken as the permeating gas, nitrogen and carbon dioxide are adsorbed, and the loss of hydrocarbon components of the natural gas is reduced.
The invention also provides a natural gas nitrogen and carbon dioxide removal device based on the method of the technical scheme, which comprises the following steps: an adsorption tank; and the interior of the adsorption tank is filled with a molecular sieve. In the present invention, the structure and composition of the molecular sieve are the same as those described above and will not be described herein.
In the present invention, the number of the adsorption tanks is preferably plural, and more preferably 4; the adsorption tanks are connected in parallel. The invention realizes the continuous production of removing nitrogen and carbon dioxide by switching the operation of a plurality of adsorption tanks. In a specific embodiment of the present invention, at least one of the adsorption tanks is in an adsorption state and the remaining adsorption tanks are in a regeneration state. The invention adopts a plurality of adsorption tanks for adsorption and desorption, realizes the smooth pressure change process in the adsorption and desorption process, and avoids bed layer penetration and molecular sieve crushing caused by severe pressure fluctuation.
In the invention, the adsorption tank preferably comprises a cylinder body, and a packing pressing plate, a molecular sieve and a packing supporting plate which are sequentially arranged in the cylinder body from top to bottom. The invention has no special requirements on the specific structures and materials of the packing press plate and the packing support plate, and the packing press plate and the packing support plate which are well known by the technical personnel in the field can be adopted. The adsorption tank provided by the invention can ensure that natural gas uniformly passes through the molecular sieve layer, and the adsorption effect is ensured.
In the present invention, the filling amount (kg) of the molecular sieve in each of the adsorption tanks is preferably calculated as gas amount per hour/4 × nitrogen content (mol%)/45 of raw natural gas.
As an embodiment of the invention, the device provided by the invention further comprises a vacuum pump, wherein the air inlet of the vacuum pump is communicated with the air outlet of the adsorption tank. The invention utilizes the vacuum pump to vacuumize the adsorption tank, reduces the pressure of the adsorption tank to the analytic pressure and realizes the regeneration of the molecular sieve. In the present invention, the vacuum pump preferably includes one or more of a water ring vacuum pump, a diaphragm vacuum pump and a piston vacuum pump.
As an embodiment of the present invention, the apparatus provided by the present invention further comprises a purge gas buffer tank and a vacuum pump buffer tank; the gas inlet of the purified gas buffer tank is communicated with the discharge hole of the adsorption tank; and the air inlet of the vacuum pump buffer tank is communicated with the air outlet of the vacuum pump. The invention utilizes the purified natural gas buffer tank to store purified natural gas and utilizes the vacuum pump buffer tank to store the analyzed nitrogen and carbon dioxide.
As an embodiment of the invention, the device provided by the invention further comprises a separator, wherein the air outlet of the separator is communicated with the air inlet of the adsorption tank. The invention utilizes the separator to separate and filter free water, free hydrocarbon and solid particle impurities contained in the raw natural gas. In the present invention, the separator preferably includes one or more of a gravity separator, a filtration separator and a coalescing filtration separator.
The device provided by the invention further comprises a plurality of switch valves for controlling the switch of each passage.
The device provided by the invention further comprises a PLC control system, and the PLC control system is in telecommunication connection with the switch valve.
In a specific embodiment of the invention, the natural gas nitrogen and carbon dioxide removal device is shown in fig. 1 and comprises a separator, an adsorption tank, a purified gas buffer tank, a vacuum pump buffer tank, a switch valve and a PLC control system; the gas inlet of the separator is communicated with a raw natural gas incoming pipeline; the gas outlet of the separator is communicated with the gas inlet of an adsorption tank, and a molecular sieve with the pore diameter of more than 0.36nm and less than 0.38nm is filled in the adsorption tank; the discharge hole of the adsorption tank is communicated with the air inlet of the purified gas buffer tank; the gas outlet of the purified gas buffer tank is communicated with an external pipeline; the air inlet of the vacuum pump is communicated with the air outlet of the adsorption tank, and the adsorption tank is vacuumized by the vacuum pump; the air outlet of the vacuum pump is communicated with the air inlet of the vacuum pump buffer tank, and the air outlet of the vacuum pump buffer tank is communicated with the atmosphere; the PLC control system controls the opening and closing actions of the switch valve.
The technical solution of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Examples 1 to 12
The natural gas is denitrogenated and carbon dioxide is carried out using the apparatus shown in figure 1: comprises a separator 1 and four parallel-connected absorbersAn adsorption tank 2-1, an adsorption tank 2-2, an adsorption tank 2-3, an adsorption tank 2-4, a purified gas buffer tank 4, a vacuum pump 5, a vacuum pump buffer tank 6, a switch valve 7 and a PLC control system 8; the gas inlet of the separator 1 is communicated with a raw natural gas incoming pipeline; the air outlet of the separator 1 is independently communicated with the air inlets of four adsorption tanks, and each adsorption tank is filled with 10m3Molecular sieve 3 with pore diameter of 0.37 nm; the discharge ports of the four adsorption tanks are independently communicated with the air inlet of the purified gas buffer tank 4; the gas outlet of the purified gas buffer tank 4 is communicated with an external pipeline; the air inlet of the vacuum pump 5 is independently communicated with the air outlet of each adsorption tank; the air outlet of the vacuum pump 5 is communicated with the air inlet of the vacuum pump buffer tank 6, and the air outlet of the vacuum pump buffer tank 6 is communicated with the atmosphere; the PLC control system 8 controls the opening and closing operation of the on-off valve 7.
Adsorption state: gas mixing amount is 100Nm3Introducing raw material natural gas at the temperature of 20-30 ℃ into a separator, and separating and filtering free water, free hydrocarbon and solid particle impurities contained in the raw material natural gas; the filtered natural gas enters an adsorption tank 2-1 and an adsorption tank 2-2 under certain pressure, nitrogen and carbon dioxide in the natural gas are adsorbed under the adsorption action of a molecular sieve, and the obtained purified natural gas enters a purified gas buffer tank from the top of the adsorption tank; after the adsorption is saturated, stopping introducing the filtered natural gas into the adsorption tank 2-1 and the adsorption tank 2-2, and introducing the filtered natural gas into the adsorption tank 2-3 and the adsorption tank 2-4 for continuous adsorption;
a regeneration state: opening switch valves on pipelines connecting the adsorption tank 2-1 and the adsorption tank 2-2 with the vacuum pump, gradually reducing the pressure in the adsorption tank to normal pressure, starting the vacuum pump to vacuumize the adsorption tank, stopping vacuumizing after the vacuum degree reaches-55 kPa, analyzing for less than 10min, introducing nitrogen and carbon dioxide obtained by analysis into a buffer tank of the vacuum pump, and enabling the adsorption tank to enter an adsorption state again.
The component contents of the raw natural gas, the pressure of the natural gas introduced into the adsorption tank (adsorption pressure), the component contents of the purified natural gas obtained, and the removal rates of nitrogen and carbon dioxide in each example are shown in table 1.
Table 1 composition content, adsorption pressure of raw natural gas, purified natural gas obtained in examples 1 to 12
Gas component content and nitrogen and carbon dioxide removal rate
As can be seen from Table 1, the method provided by the invention can effectively remove nitrogen and carbon dioxide in the raw material natural gas, and is simpler and more convenient, and has small adsorbent dosage and lower operation cost.
The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.
Claims (10)
1. A natural gas nitrogen and carbon dioxide removing method based on a controlled-aperture molecular sieve comprises the following steps:
adsorbing nitrogen and carbon dioxide in the raw material natural gas by using a molecular sieve to obtain purified natural gas; the pore diameter of the molecular sieve is more than 0.36nm and less than 0.38 nm.
2. The natural gas denitrogenation and carbon dioxide process according to claim 1, characterized in that the pressure of adsorption is 0.3-1.0 MPa.
3. The natural gas denitrogenation and carbon dioxide process according to claim 1, characterized in that the molar content of nitrogen in the feed natural gas is less than or equal to 15%; the molar content of the carbon dioxide is less than or equal to 10 percent.
4. The natural gas denitrification and carbon dioxide process according to claim 1, wherein the molecular sieve has an adsorption capacity for nitrogen of 45-60 mL/g; the adsorption capacity of the molecular sieve to carbon dioxide is 10-15 mg/g.
5. The natural gas denitrogenation and carbon dioxide process according to claim 1, characterized in that after said adsorption, a molecular sieve enriched in nitrogen and carbon dioxide is also obtained; and resolving the molecular sieve rich in nitrogen and carbon dioxide to obtain a mixed gas of nitrogen and carbon dioxide and a regenerated molecular sieve.
6. The natural gas denitrogenation and carbon dioxide process according to claim 5, characterized in that the desorption pressure is between-50 and-60 kPa.
7. The natural gas denitrogenation and carbon dioxide process of claim 1 wherein the molecular sieve is a titanium silicate molecular sieve.
8. A natural gas denitrogenation and carbon dioxide plant based on the process according to any one of claims 1 to 7, comprising: an adsorption tank; and the interior of the adsorption tank is filled with a molecular sieve.
9. The apparatus of claim 8, further comprising a vacuum pump; and the air inlet of the vacuum pump is communicated with the air outlet of the adsorption tank.
10. The apparatus of claim 9, further comprising a purge gas buffer tank and a vacuum pump buffer tank; the gas inlet of the purified gas buffer tank is communicated with the discharge hole of the adsorption tank; and the air inlet of the vacuum pump buffer tank is communicated with the air outlet of the vacuum pump.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110828746.1A CN113355143A (en) | 2021-07-22 | 2021-07-22 | Natural gas nitrogen and carbon dioxide removing method and device based on controllable-aperture molecular sieve |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110828746.1A CN113355143A (en) | 2021-07-22 | 2021-07-22 | Natural gas nitrogen and carbon dioxide removing method and device based on controllable-aperture molecular sieve |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN113355143A true CN113355143A (en) | 2021-09-07 |
Family
ID=77540191
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110828746.1A Pending CN113355143A (en) | 2021-07-22 | 2021-07-22 | Natural gas nitrogen and carbon dioxide removing method and device based on controllable-aperture molecular sieve |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113355143A (en) |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101935032A (en) * | 2010-09-03 | 2011-01-05 | 同济大学 | Preparation method and use of carbon molecular sieve |
| CN102068915A (en) * | 2010-06-11 | 2011-05-25 | 苏州信望膜技术有限公司 | Double-layer hollow fiber mixed matrix membrane and preparation method thereof |
| CN108031240A (en) * | 2017-12-18 | 2018-05-15 | 洛阳健阳科技有限公司 | A kind of device based on HEU type zeolite molecular sieve separation of methane and nitrogen |
| CN108043172A (en) * | 2017-12-18 | 2018-05-18 | 洛阳健阳科技有限公司 | A kind of method of zeolite molecular sieve separation of methane and nitrogen |
| CN109126381A (en) * | 2018-09-13 | 2019-01-04 | 北京北大先锋科技有限公司 | A kind of method that pressure-variable adsorption removes carbon dioxide in industrial gasses |
| CN110773120A (en) * | 2019-11-08 | 2020-02-11 | 四川大学 | Metal salt modified molecular sieve and preparation method and application thereof |
-
2021
- 2021-07-22 CN CN202110828746.1A patent/CN113355143A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102068915A (en) * | 2010-06-11 | 2011-05-25 | 苏州信望膜技术有限公司 | Double-layer hollow fiber mixed matrix membrane and preparation method thereof |
| CN101935032A (en) * | 2010-09-03 | 2011-01-05 | 同济大学 | Preparation method and use of carbon molecular sieve |
| CN108031240A (en) * | 2017-12-18 | 2018-05-15 | 洛阳健阳科技有限公司 | A kind of device based on HEU type zeolite molecular sieve separation of methane and nitrogen |
| CN108043172A (en) * | 2017-12-18 | 2018-05-18 | 洛阳健阳科技有限公司 | A kind of method of zeolite molecular sieve separation of methane and nitrogen |
| CN109126381A (en) * | 2018-09-13 | 2019-01-04 | 北京北大先锋科技有限公司 | A kind of method that pressure-variable adsorption removes carbon dioxide in industrial gasses |
| CN110773120A (en) * | 2019-11-08 | 2020-02-11 | 四川大学 | Metal salt modified molecular sieve and preparation method and application thereof |
Non-Patent Citations (1)
| Title |
|---|
| 李香文: "《化学》", 北京：人民教育出版社, pages: 295 - 296 * |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US6402813B2 (en) | Process for purifying a gas by adsorption of the impurities on several active carbons | |
| US8192527B2 (en) | Purification method by hydrogen adsorbtion with cogeneration of CO2 stream pressure | |
| CN1026469C (en) | Pressure swing adsorption method for separating gaseous mixtures | |
| US4256469A (en) | Repressurization technique for pressure swing adsorption | |
| CN1123193A (en) | Hydrogen recovery by adsorbent membranes | |
| CN202569898U (en) | Nitrogen producing device | |
| CN100423811C (en) | Pressure-variation absorption method for separating and recovering adsorbed phase products from mixed gas | |
| CN110697655A (en) | Method and system device for recovering hydrogen through membrane separation and concentration | |
| CN104891439A (en) | Method for increasing of recovery rate of hydrogen from reformed gas | |
| CN113350968A (en) | Hydrogen extraction device and process for recovering tail gas components by using synthetic hydrogen | |
| CN110813022A (en) | Multi-bed rapid cycle dynamics PSA | |
| CN211799895U (en) | Process system for separating mixed gas containing hydrogen chloride and hydrogen | |
| CN113797704B (en) | Safe and efficient step purification method and system for preparing natural gas from low-concentration gas | |
| US11701612B2 (en) | Multi-stage PSA process to remove contaminant gases from raw methane streams | |
| CN201930684U (en) | Non-deep-cold transforming, adsorbing and separating device for oxygen and argon mixture | |
| JPS60176901A (en) | Method for concentrating and purifying hydrogen, etc. in mixed gas containing at least hydrogen by using adsorption | |
| CN113184850A (en) | Method and device for purifying high-purity carbon dioxide gas | |
| US10730005B2 (en) | Porous materials for natural gas liquids separations | |
| CN113355143A (en) | Natural gas nitrogen and carbon dioxide removing method and device based on controllable-aperture molecular sieve | |
| CN102091501A (en) | Upper and lower pressure-equalizing pressure swing adsorption method | |
| CN214780753U (en) | Device for preparing high-purity oxygen based on coupling separation technology | |
| CN112744789B (en) | Oxygen generation method and device based on coupling separation technology | |
| CN214780752U (en) | Oxygen generating device based on coupling separation technology | |
| CN102600699A (en) | Pressure-variable adsorption gas separation device | |
| CN1330974A (en) | Vacuum pressure-variable process for removing ethane or hydrocarbons over ethane from gas-state hydrocarbon |
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 |