CN214087706U - Pressure swing adsorption purification hydrogen system - Google Patents
Pressure swing adsorption purification hydrogen system Download PDFInfo
- Publication number
- CN214087706U CN214087706U CN202120016673.1U CN202120016673U CN214087706U CN 214087706 U CN214087706 U CN 214087706U CN 202120016673 U CN202120016673 U CN 202120016673U CN 214087706 U CN214087706 U CN 214087706U
- Authority
- CN
- China
- Prior art keywords
- pipeline
- pressure
- gas
- hydrogen
- line
- 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
Images
Landscapes
- Separation Of Gases By Adsorption (AREA)
- Hydrogen, Water And Hydrids (AREA)
Abstract
The utility model discloses a pressure swing adsorption purification hydrogen system solves current pressure swing adsorption purification hydrogen equipment C atom (CO, CO) in product hydrogen2And CH4) The hydrogen recovery rate is low when the content requirement is strict. The utility model discloses an adsorption tower, mixed feed gas pipeline, desorption gas pipeline, in the same direction as putting pipeline, uniform pressure pipeline, first voltage-sharing and finally pipeline, product gas outward transport pipeline, contain hydrogen feed gas pipeline, nitrogen gas pipeline, flowmeter, governing valve, flush the governing valve and fill the governing valve eventually. When the product hydrogen requires CO and CO2And CH4Strictly, nitrogen is added into the raw material gas, so that the molar content of the hydrogen in the product is ensured to be more than 99.9 percent every timeIncrease raw material gas flow 1% nitrogen gas, the hydrogen rate of recovery can increase 0.3 ~ 2 percentage points, compares with conventional pressure swing adsorption purification hydrogen system, the utility model discloses the change is little, and it is obvious to bring the benefit, not only is fit for newly-built device, also is fit for current device transformation.
Description
Technical Field
The utility model belongs to the technical field of pressure swing adsorption gas separation, concretely relates to pressure swing adsorption purification hydrogen system.
Background
The pressure swing adsorption technology is widely applied to the separation of various mixed gases, such as the purification of oxygen and nitrogen from air, the purification of carbon dioxide from industrial tail gas rich in carbon dioxide, the purification of carbon monoxide from mixed gas rich in carbon monoxide, and the purification of hydrogen from various mixed gases rich in hydrogen, wherein hydrogen is used as important industrial gas, the demand is large, the application range is wide, and therefore, the research and development of the technology for purifying hydrogen by pressure swing adsorption are deeper.
For example, patent CN 1984705B discloses a continuous feeding three-bed pressure swing adsorption system, which realizes a twelve-step circulation process of pressure swing adsorption with two-step pressure equalization of three adsorption towers; in order to improve the efficiency of large plants, patent US6565628B2 discloses a sixteen-tower cycle process, patent CN103534002B discloses a twelve-to sixteen-tower process cycle; in order to enhance the regeneration effect of the adsorbent; patent CN1298410C discloses a pressure swing adsorption process with two sequential discharge tanks, which realizes a two-time staggered flushing process, and patent CN100588449C discloses a multiple-time sequential discharge staggered flushing pressure swing adsorption process, which realizes a three-time staggered flushing process; patent CN106039917B discloses porous adsorbent material in order to increase the adsorption rate of the adsorbent.
The largest application of hydrogen is the hydrogenation reaction process in the field of petrochemical industry, and the purity requirement of the chemical reaction process on the hydrogen is not high, generally 99.9% (mol/mol), but the C atom content in the hydrogen, such as CO and CO2、CH4The requirements are strict, and CO are generally required2Less than 20ppmv, individual process requirements for CO less than 5ppmv or even 1ppmv, and many industrial hydrogen production such as hydrocarbon steam reforming hydrogen production, coal hydrogen production and some industrial tail gas hydrogen production all contain a certain proportion of CO and CO in raw material gas before hydrogen purification2And CH4To ensure pressure swing adsorption purificationThe hydrogen contains 10ppmv or even lower content of C atoms, and the purity of the hydrogen is required to reach 99.99-99.999% (mol/mol) under many conditions, so that the recovery rate of the pressure swing adsorption purified hydrogen is limited to a certain extent.
SUMMERY OF THE UTILITY MODEL
The to-be-solved technical problem of the utility model is: provides a pressure swing adsorption hydrogen purification system, which solves the problem that the existing pressure swing adsorption hydrogen purification equipment can purify C atoms (CO and CO) in product hydrogen2And CH4) The hydrogen recovery rate is low when the content requirement is strict.
In order to achieve the above object, the utility model adopts the following technical scheme:
a pressure swing adsorption hydrogen purification system comprises at least three adsorption towers, a mixed raw material gas conveying pipeline and a desorption gas pipeline which are connected into the adsorption towers, and a flushing inlet pipeline, a forward discharge pipeline, a pressure equalizing pipeline, a first pressure equalizing and final boosting pipeline and a product gas output pipeline which are connected out of the adsorption towers; the mixed raw material gas conveying pipeline is connected with a hydrogen-containing raw material gas conveying pipeline and a nitrogen conveying pipeline, a first flowmeter is arranged on the hydrogen-containing raw material gas conveying pipeline, a second flowmeter and an adjusting valve are arranged on the nitrogen conveying pipeline, and the first pressure equalizing and final boosting pipeline is communicated with the product gas output pipeline through a final-charging adjusting valve.
Furthermore, a raw material gas program control valve is arranged on the raw material gas conveying pipeline, and a product gas program control valve is arranged on the product gas outward conveying pipeline.
Furthermore, a desorption gas programmable valve is arranged on the desorption gas pipeline.
Further, the desorption gas pipeline comprises a reverse gas pipeline and a flushing outlet pipeline, and the desorption gas program control valve comprises a reverse gas program control valve arranged on the reverse gas pipeline and a flushing program control valve arranged on the flushing outlet pipeline.
Furthermore, a flushing inlet program control valve is arranged on the flushing inlet pipeline.
Furthermore, a sequential discharge program control valve is arranged on the sequential discharge pipeline.
Further, a pressure equalizing program control valve is arranged on the pressure equalizing pipeline.
Furthermore, the pressure equalizing pipeline comprises a fourth pressure equalizing pipeline/a fifth pressure equalizing pipeline and a second pressure equalizing pipeline/a third pressure equalizing pipeline, and the pressure equalizing programmable valve comprises a fourth pressure equalizing valve/a fifth pressure equalizing programmable valve arranged on the fourth pressure equalizing pipeline/the fifth pressure equalizing pipeline and a second pressure equalizing valve/a third pressure equalizing programmable valve arranged on the second pressure equalizing pipeline/the third pressure equalizing pipeline.
Furthermore, a first pressure equalizing and final boosting program control valve is arranged on the first pressure equalizing and final boosting pipeline.
Further, the flushing inlet line is communicated with the in-line pipeline through a flushing regulating valve, or the in-line pipeline is communicated with the flushing inlet line through one to two in-line buffer tanks and the flushing regulating valve.
Compared with the prior art, the utility model discloses following beneficial effect has:
the utility model has the advantages of simple structure and scientific and reasonable design, convenient to use, the adsorption capacity of nitrogen gas on various adsorbents such as molecular sieve, active carbon, silica gel all is less than CH4CO and CO2In the adsorption capacity of (2) in the presence of a catalyst selected from the group consisting of2、CO、CO2、CH4、CnHmWhen purifying hydrogen from a mixture of hydrogen and nitrogen, the nitrogen (except hydrogen) first penetrates the adsorbent bed and then is CH4、CO、CO2Thus, when the C atoms in the product hydrogen are CO, CO2、CH4When the requirements are strict, if N in the raw material gas is2The low content of the hydrogen leads to high purity of the product hydrogen, for example, when the C atom of the product hydrogen is controlled at 10ppmv, the purity of the product hydrogen is up to 99.99-99.999%. By using N2The adsorption capacity on the adsorbent is small and is prior to CO and CO2、CH4Pierce through the characteristics of adsorption bed, through wherein add nitrogen gas at the raw materials, the impurity proportion in the feed gas has been adjusted, nitrogen gas content has been increased, thereby when the C atom of the same index of product gas control, have more nitrogen gas to get into product hydrogen, the purity of product hydrogen has been reduced, when satisfying the index of hydrogen purity 99.9%, the product gas end that is closer to the adsorption tower is compared with not adding nitrogen gas in the absorption front of hydrogen, thereby the rate of recovery of hydrogen has been increased, the nitrogen gas that increases 1% every in the feed gas can promote hydrogen returnsThe yield is about 0.3-2%. The utility model discloses except being applicable to newly-built device, also be fit for the transformation that current pressure swing adsorption carried hydrogen device.
Drawings
FIG. 1 is a diagram of a pressure swing adsorption hydrogen purification system of the present invention.
FIG. 2 is a diagram of a pressure swing adsorption hydrogen purification system with a buffer tank
Fig. 3 is the adsorption isotherm of four gases on a molecular sieve of a certain type at 25 ℃.
Figure 4 is the distribution curve of hydrogen in the adsorption bed at the end of the adsorption of the present invention.
Fig. 5 shows the distribution of hydrogen in the top region of the adsorption bed at the end of the adsorption process.
Wherein, the names corresponding to the reference numbers are:
1-mixed raw material gas conveying pipeline, 2-flushing pipeline, 3-reverse gas discharging pipeline, 4-flushing pipeline, 5-forward discharging pipeline, 6-fourth pressure equalizing/fifth pressure equalizing pipeline, 7-second pressure equalizing/third pressure equalizing pipeline, 8-first pressure equalizing and final boosting pipeline, 9-product gas outward conveying pipeline, 10-final charging regulating valve, 11-flushing regulating valve, 12-hydrogen-containing raw material gas conveying pipeline, 13-nitrogen conveying pipeline, 14-first flowmeter, 15-second flowmeter, 16-regulating valve, 17-hydrogen product, 18-adsorption tower, 19-forward discharging buffer tank, 1-raw material gas program control valve, 2 XX-flushing outlet program control valve, 3 XX-reverse gas discharging program control valve, 4 XX-flushing inlet program control valve, 5 XX-forward-release program control valve, 6 XX-fourth pressure equalizing/fifth pressure equalizing program control valve, 7 XX-second pressure equalizing/third pressure equalizing program control valve, 8 XX-first pressure equalizing and final boosting program control valve and 9 XX-product gas program control valve.
Wherein XX in 1XX, 2XX, 3XX, 4XX, 5XX, 6XX, 7XX, 8XX and 9XX is the last two digits of the adsorption tower number, as shown in fig. 1, 1XX, 2XX, 3XX, 4XX, 5XX, 6XX, 7XX, 8XX and 9XX corresponding to the adsorption tower number 003 are 103, 203, 303, 403, 503, 603, 703, 803 and 903 respectively, and so on.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings. It is to be understood that the embodiments described are only some embodiments of the invention, and not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.
In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and thus, it should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; of course, mechanical connection and electrical connection are also possible; alternatively, they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood according to specific situations by those skilled in the art.
The utility model provides a pressure swing adsorption purification hydrogen system, which comprises at least three adsorption towers 18, a mixed raw material gas conveying pipeline 1 and a desorption gas pipeline which are connected into the adsorption towers 18, and a flushing inlet pipeline 4, a sequential discharge pipeline 5, a pressure equalizing pipeline, a first pressure equalizing and final boosting pipeline 8 and a product gas output pipeline 9 which are connected out of the adsorption towers 18; the mixed raw material gas conveying pipeline 1 is connected with a hydrogen-containing raw material gas conveying pipeline 12 and a nitrogen conveying pipeline 13, the hydrogen-containing raw material gas conveying pipeline 12 is provided with a first flowmeter 14, the nitrogen conveying pipeline 13 is provided with a second flowmeter 15 and an adjusting valve 16, and the first pressure equalizing and final boosting pipeline 8 is communicated with the product gas output pipeline 9 through a final-charging adjusting valve 10. The cis-bleeding line 5 and the flushing inlet line 4 are communicated with each other by a flushing regulating valve 11, or the cis-bleeding line 5 and the flushing inlet line 4 are communicated with each other by one or two cis-bleeding buffer tanks 19 and a flushing regulating valve.
The raw material gas conveying pipeline 1 is provided with a raw material gas program control valve, and the product gas outward conveying pipeline is provided with a product gas program control valve. The flushing inlet pipeline is provided with a flushing inlet program control valve 1 XX. The forward discharge pipeline 5 is provided with a forward discharge program control valve 5 XX. The pressure equalizing pipeline is provided with a pressure equalizing program control valve, the pressure equalizing pipeline comprises a fourth pressure equalizing/fifth pressure equalizing pipeline 6 and a second pressure equalizing/third pressure equalizing pipeline 7, and the pressure equalizing program control valve comprises a fourth pressure equalizing/fifth pressure equalizing program control valve 6XX arranged on the fourth pressure equalizing/fifth pressure equalizing pipeline 6 and a second pressure equalizing/third pressure equalizing program control valve 7XX arranged on the second pressure equalizing/third pressure equalizing pipeline 7. And a first pressure equalizing and final boosting program control valve 8XX is arranged on the first pressure equalizing and final boosting pipeline 8. The desorption gas line is provided with a desorption gas programmable valve, wherein the desorption gas line can be a single line and is provided with a desorption gas programmable valve, but preferably, the desorption gas line comprises a reverse gas discharge line 3 and a flushing discharge line 2, and the desorption gas programmable valve comprises a reverse gas discharge programmable valve 3XX arranged on the reverse gas discharge line 3 and a flushing discharge valve 2XX arranged on the flushing discharge line 2.
The utility model also provides a pressure swing adsorption purification hydrogen method of pressure swing adsorption purification hydrogen system adopts at least three adsorption tower to carry out pressure swing adsorption purification hydrogen through the recirculation step respectively, and every adsorption tower experiences the recirculation step in proper order for adsorption step, cisoid step, reverse step, regeneration step and the reverse step of stepping up. Each adsorption tower is filled with at least one adsorbent which can selectively and easily adsorb other gas components except hydrogen in the feed gas conveying pipeline, and the adsorbents filled in all the adsorption towers can selectively and easily adsorb all other gas components except hydrogen in the feed gas conveying pipeline. The mixed raw material gas in the mixed raw material gas conveying pipeline enters an adsorption tower for adsorption in the adsorption process, and the volume flow ratio of the nitrogen in the nitrogen conveying pipeline to the hydrogen-containing raw material gas in the hydrogen-containing raw material gas conveying pipeline is less than or equal to 0.1; preferably, the volume flow ratio of the nitrogen in the nitrogen conveying pipeline to the hydrogen-containing raw material gas in the hydrogen-containing raw material gas conveying pipeline is less than or equal to 0.07; preferably, the molar content of nitrogen in the nitrogen conveying line is greater than or equal to 99.9%; preferably, the adsorption tower is filled with a molecular sieve adsorbent, or a composite adsorption bed consisting of one or more of molecular sieve, activated alumina, activated carbon and silica gel
The adsorption step in the pressure swing adsorption hydrogen purification method of the utility model is that the hydrogen purification method at least contains CO and CO2And CH4After nitrogen is added into the hydrogen-containing raw material gas of the one impurity gas component, the mixed raw material gas enters the adsorption tower from the feed end of the adsorption tower under the pressure of 1.0-7.0 MPa, the non-hydrogen impurities are adsorbed by the adsorbent, and the hydrogen product flows out from the discharge end of the adsorption tower.
The forward pressure reduction step in the pressure swing adsorption hydrogen purification method of the utility model is that gas in the adsorption tower flows out of the adsorption tower along the gas flow direction during adsorption, and the pressure in the adsorption tower is reduced; preferably, the forward depressurization step comprises at least two depressurization processes, and the forward depressurization step is either entirely an equalizing depressurization step or comprises both an equalizing depressurization step and a forward purge step of providing a purge regeneration gas to the regeneration adsorption column.
The utility model discloses reverse step-down in the pressure swing adsorption purification hydrogen method is that gas flow direction flows out the adsorption tower when gas is against adsorbing in the adsorption tower, and adsorption tower internal pressure reduces, and reverse step-down step contains the at least process of stepping down.
The utility model discloses regeneration step is gas flow direction outflow adsorption tower when adsorbing against in the adsorption tower impurity gas composition that the pressure swing adsorption purification hydrogen method was middle and upper, and regeneration step is in the same direction as gassing backwash regeneration step or the regeneration step of managing to find time of utilizing vacuum equipment to the adsorption tower evacuation for utilizing other adsorption towers.
The utility model discloses reverse pressure boost step is the adsorption tower after accomplishing the regeneration in the pressure swing adsorption purification hydrogen method, utilizes the gas and the product gas of cisoid step of stepping down to carry out reverse pressure boost to the adsorption tower, and the step of stepping up is the voltage-sharing when wherein accepting reverse step of stepping down gas, is final step of stepping up when accepting product gas.
The utility model has simple implementation, scientific and reasonable design, convenient use and the adsorption capacity of nitrogen on various adsorbents such as molecular sieve, active carbon and silica gel is less than CH4CO and CO2In the adsorption capacity of (2) in the presence of a catalyst selected from the group consisting of2、CO、CO2、CH4、CnHmWhen purifying hydrogen from a mixture of hydrogen and nitrogen, the nitrogen (except hydrogen) first penetrates the adsorbent bed and then is CH4、CO、CO2Thus, when the C atoms in the product hydrogen are CO, CO2、CH4When the requirements are strict, if N in the raw material gas is2The low content of the hydrogen leads to high purity of the product hydrogen, for example, when the C atom of the product hydrogen is controlled at 10ppmv, the purity of the product hydrogen is up to 99.99-99.999%. By using N2The adsorption capacity on the adsorbent is small, and the adsorbent is firstly mixed with CO and CO2、CH4Penetrate the characteristics of adsorption bed, through adding nitrogen among the raw materials, the impurity proportion in the feed gas has been adjusted, nitrogen content has been increased, thereby when the C atom of the same index of product gas control, have more nitrogen to get into in the product hydrogen, the purity of product hydrogen has been reduced, when satisfying the index of hydrogen purity 99.9%, the adsorption front edge of hydrogen compares the product gas end that is closer to the adsorption tower with not adding nitrogen, thereby the rate of recovery of hydrogen has been increased, the rate of recovery that can promote hydrogen about 0.3% -2% per increase 1% nitrogen in the feed gas. The utility model discloses except being applicable to newly-built device, also be fit for the transformation that current pressure swing adsorption carried hydrogen device.
The concentration percentages used in the present invention are mole percentages, pressure gauge, unless specifically indicated as absolute pressure.
The utility model discloses a pressure swing adsorption purification hydrogen system requires CO, CO when product hydrogen2And CH4Strictly, the nitrogen is added into the feed gas to adjust the proportion of each impurity in the feed gas, thereby ensuring that the molar content of the hydrogen in the product is more than 99.9 percent and increasing the content of each impurityThe hydrogenation gas rate of recovery, every increase raw material gas flow 1% nitrogen gas, the hydrogen rate of recovery can increase 0.3 ~ 2 percentage points, compares with conventional pressure swing adsorption purification hydrogen system, the utility model discloses the change is little, and the benefit of bringing is obvious, not only is fit for newly-built device, also is fit for current device transformation.
A pressure swing adsorption gas separation system for purifying hydrogen from a hydrogen-rich gas mixture, the system comprising more than three adsorption towers respectively subjected to repeated circulation steps, each adsorption tower is filled with only one adsorbent which is selective to adsorb and can be easily adsorbed, and the repeated circulation steps experienced by each adsorption tower are an adsorption step (a), a forward depressurization step (b), a reverse depressurization step (c), a regeneration step (d) and a pressurization step (e) in sequence, wherein:
an adsorption step (a): at least CO and CO2And CH4After nitrogen is added into the hydrogen-containing raw material gas of the first impurity, the mixed raw material gas enters the adsorption tower from the feed end of the adsorption tower under the pressure of 1.0-7.0 MPa, the non-hydrogen impurities are adsorbed by the adsorbent, and the hydrogen product flows out from the discharge end of the adsorption tower.
Forward depressurization step (b): the gas in the adsorption tower flows out of the adsorption tower along the gas flow direction during adsorption, the pressure in the adsorption tower is reduced, the forward pressure reduction step comprises at least two pressure reduction processes, and the forward pressure reduction step is a pressure-equalizing pressure reduction step or comprises a pressure-equalizing pressure reduction step and two steps of a forward release step for providing flushing regeneration gas for the regeneration adsorption tower.
And (c) reverse pressure reduction: the gas in the adsorption tower flows out of the adsorption tower against the gas flow during adsorption, the pressure in the adsorption tower is reduced, and the reverse pressure reduction step comprises at least one pressure reduction process.
A regeneration step (d): impurities adsorbed in the adsorption tower flow out of the adsorption tower against the gas flow during adsorption, and the regeneration step is a forward-exhaust gas countercurrent flushing regeneration step of other adsorption towers or an evacuation regeneration step of vacuumizing the adsorption tower by using vacuum equipment.
A pressure increasing step (e): and (3) boosting the pressure of the adsorption tower by utilizing the gas and the product gas in the forward pressure reduction step, wherein the pressure equalizing and boosting step is carried out when the gas in the forward pressure reduction step is received, and the final pressure boosting step is carried out when the product gas is received.
The pressure of the nitrogen added into the hydrogen-rich raw material gas is greater than or equal to that of the hydrogen-rich raw material gas, the molar content of the nitrogen is more than 99.9 percent, and the temperature of the nitrogen is 0-40 ℃ at normal temperature; the ratio of the volume flow rate of the nitrogen gas added into the raw gas rich in hydrogen to the volume flow rate of the raw gas rich in hydrogen is less than or equal to 0.1, and preferably less than or equal to 0.07. The volume flow of nitrogen gas added into the hydrogen-rich feed gas is changed along with the change of the flow of the feed gas.
In order to make the technical solution of the present invention better understood by those skilled in the art, twelve adsorption towers are illustrated as an example.
As shown in fig. 1, the system for purifying hydrogen through pressure swing adsorption of the present embodiment includes twelve adsorption towers 18(001 to 012), a mixed raw material gas delivery pipeline 1, a product gas delivery pipeline 9, a reverse gas release pipeline 3, a flushing outlet pipeline 2, a first pressure equalizing and final pressure boosting pipeline 8, a second pressure equalizing/third pressure equalizing pipeline 7, a fourth pressure equalizing/fifth pressure equalizing pipeline 6, a forward discharge pipeline 5, a flushing inlet pipeline 4, a hydrogen-containing raw material gas delivery pipeline 12, a nitrogen gas delivery pipeline 13, and program control valves 101 to 912, wherein a first flow meter 14 is disposed on the hydrogen-containing raw material gas delivery pipeline 12, a second flow meter 15 and a regulating valve 16 are disposed on the nitrogen gas delivery pipeline 13, the flushing regulating valve 11 is communicated with the forward discharge pipeline 5 and the flushing pipeline 6, and the final filling regulating valve 10 is connected with the product gas delivery pipeline 9 and the first pressure equalizing and final pressure boosting pipeline 8. A sequential buffer tank may also be added in this example, as shown in figure 2.
In the example (figure 1), a 12-3-5/P flow path is adopted, and the process sequence is shown in table 1, namely 12 adsorption towers, 3 adsorption towers are used for adsorption at the same time, and 5 steps of pressure equalization and flushing regeneration are carried out. The pressure of the raw material gas is 3.0MPa, and the regeneration pressure is 0.02 MPa; the volume ratio of each component of the mixed raw material gas in the mixed raw material gas conveying pipeline is as follows: h2:N277: 0.5: 22.5, the purity of the product hydrogen is more than or equal to 99.9 percent; the adsorbent is molecular sieve.
Table 1 example 1 timing sequence chart
Note: a: adsorption step, 1D: a first pressure equalizing and reducing step, 2D: a second pressure equalizing and reducing step, 3D: a third pressure equalizing and reducing step, 4D: a fourth pressure equalizing and reducing step, 5D: a fifth pressure equalizing and reducing step, PP: step D: reverse amplification step, P: washing step, 5R: a fifth voltage equalizing and boosting step, 4R: a fourth voltage equalizing and boosting step, 3R: a third voltage-equalizing and boosting step, 2R: a second voltage equalizing and boosting step, 1R: a first voltage equalizing and boosting step, FR: and finally, a pressure rising step.
After the hydrogen-containing raw material gas in the hydrogen-containing raw material gas conveying pipeline 12 and the nitrogen in the nitrogen conveying pipeline 13 are mixed in the mixed raw material gas conveying pipeline 1, the mixture enters 3 adsorption towers at normal temperature and 3.0MPa for adsorption, impurities (nitrogen and carbon monoxide) are adsorbed by the adsorbent, and a hydrogen product 17 is output through a product gas output pipeline 9; the adsorption tower which finishes adsorption sequentially carries out a first pressure equalizing and reducing step, a second pressure equalizing and reducing step, a third pressure equalizing and reducing step, a fourth pressure equalizing and reducing step, a fifth pressure equalizing and reducing step and a forward releasing step so as to finish forward pressure reduction; after the forward depressurization step, depressurizing the adsorption tower against the direction of the adsorption bed, namely a reverse depressurization step, wherein reverse blowdown gas is sent out of the system through a reverse blowdown valve 3XX and a reverse blowdown pipeline 3; after reverse pressure reduction, forward pressure reduction gas of the adsorption tower in the forward discharging step is used for flushing and regenerating the adsorption tower against the direction of the adsorption bed through a forward discharging valve 5XX, a forward discharging pipeline 5, a flushing regulating valve 11, a flushing inlet pipeline 4 and a flushing inlet valve 4XX, and flushing waste gas is discharged out of the system through a flushing outlet valve 2XX and a flushing outlet pipeline 2; the adsorption tower after being washed sequentially goes through a fifth voltage-equalizing and boosting step, a fourth voltage-equalizing and boosting step, a third voltage-equalizing and boosting step, a second voltage-equalizing and boosting step, a first voltage-equalizing and boosting step and a final voltage-boosting step. The first pressure equalizing and reducing step corresponds to the first pressure equalizing and increasing step, and the two corresponding adsorption towers are communicated with a first pressure equalizing and final pressure increasing pipeline 8 through a valve 8XX to realize pressure balance; the second/third pressure equalizing and reducing step corresponds to the second/third pressure equalizing and increasing step, and the corresponding two adsorption towers are communicated with a second pressure equalizing/third pressure equalizing pipeline 7 through a valve 7XX to realize pressure balance; the fourth/fifth pressure equalizing and reducing step corresponds to the fourth/fifth pressure equalizing and increasing step, and the corresponding two adsorption towers are communicated with a fourth pressure equalizing/fifth pressure equalizing pipeline 6 through a valve 6XX to realize pressure balance; in the final pressure increasing step, the product gas 17 passes through the final charge regulating valve 10 and then enters the adsorption tower for final pressure increase through the first pressure equalizing and final pressure increasing pipeline 8 and the final pressure increasing valve 8XX until the pressure of the adsorption tower reaches the adsorption pressure.
The flow rate of nitrogen gas in the hydrogen-containing raw gas conveying pipeline 12 and the nitrogen gas conveying pipeline 13 is controlled by the regulating valve 16, so that the flow rate of the nitrogen gas and the flow rate of the hydrogen-containing raw gas are maintained at a certain proportion, and when the flow rate of the hydrogen-containing raw gas is changed, the flow rate of the nitrogen gas is regulated by the regulating valve 16.
The CO content of the product hydrogen was controlled at 10ppmv, and the recovery rate of the product hydrogen and the molar content of the product hydrogen were varied with the amount of nitrogen added as shown in Table 2. With the increase of the addition of the nitrogen, the recovery rate of the hydrogen is gradually increased, and the hydrogen tax rate is increased by 1 percentage point after 2 percent of the nitrogen is added.
The adsorption capacity of nitrogen on various adsorbents such as molecular sieve, activated carbon and silica gel is less than CH4CO and CO2Adsorption capacity of (2), as shown in FIG. 3, H2、N2、CH4The adsorption isotherm of CO on a molecular sieve of a certain type, and the adsorption isotherm of nitrogen is positioned in hydrogen and CH4And CO.
In the presence of N2、CO、CO2、CH4、CnHmAnd H2Purifying H from the gas mixture2When N is present2First through the adsorbent bed (except for hydrogen) and then CH4、CO、CO2Thus, when the C atoms in the product hydrogen are CO, CO2、CH4When the requirements are strict, if the content of nitrogen in the feed gas is low, the purity of the product hydrogen is very high, and when the CO atom of the product hydrogen is controlled to be 10ppmv, the purity of the product hydrogen in the example is 99.996%, the content of hydrogen after 2% of nitrogen is added is 99.978%, and the content of hydrogen after 5% of nitrogen is added is 99.921%.
The nitrogen gas has small adsorption capacity on the adsorbent and is prior to CO and CO2、CH4The characteristics of the penetrating adsorption bed are that N is added into the raw gas containing hydrogen2The impurity proportion in the feed gas is adjusted, the nitrogen content is increased, so that when the product gas controls C atoms with the same index, more nitrogen enters the product hydrogen, the purity of the product hydrogen is reduced, and when the index of 99.9 percent of the hydrogen purity is met, the adsorption front edge of the hydrogen and the adsorption front edge of the hydrogen are not added with N2Compare the product gas end that is closer to the adsorption tower to increased the rate of recovery of hydrogen, figure 4 is the distribution curve of hydrogen in the adsorption bed when the adsorption finishes before and after utilizing pressure swing adsorption's mathematical model simulation to add nitrogen, figure 5 is the hydrogen distribution curve in adsorption bed top region, obviously sees that the adsorption front edge of hydrogen is closer to the top of adsorption bed after adding nitrogen.
TABLE 2 influence of nitrogen addition on hydrogen recovery at a CO content of 10ppmv in the product gas
Note: k is the ratio of the volume flow rates of the nitrogen gas 13 and the feed gas 12.
Finally, it should be noted that: the above embodiments are only preferred embodiments of the present invention to illustrate the technical solution of the present invention, but not to limit the same, and certainly not to limit the scope of the present invention; although the present invention has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention; that is, the technical problems solved by the present invention are still consistent with the present invention, and all the modifications or colors made in the spirit and the idea of the main design of the present invention are included in the protection scope of the present invention; in addition, will the technical scheme of the utility model direct or indirect application is in other relevant technical field, all including on the same reason the utility model discloses an in the patent protection scope.
Claims (10)
1. A pressure swing adsorption hydrogen purification system is characterized by comprising at least three adsorption towers, a mixed raw material gas conveying pipeline and a desorption gas pipeline which are connected into the adsorption towers, and a flushing inlet pipeline, a forward discharge pipeline, a pressure equalizing pipeline, a first pressure equalizing and final boosting pipeline and a product gas output pipeline which are connected out of the adsorption towers; the mixed raw material gas conveying pipeline is connected with a hydrogen-containing raw material gas conveying pipeline and a nitrogen conveying pipeline, a first flowmeter is arranged on the hydrogen-containing raw material gas conveying pipeline, a second flowmeter and an adjusting valve are arranged on the nitrogen conveying pipeline, and the first pressure equalizing and final boosting pipeline is communicated with the product gas output pipeline through a final-charging adjusting valve.
2. The pressure swing adsorption hydrogen purification system of claim 1, wherein a feed gas programmable valve is disposed on the feed gas delivery line, and a product gas programmable valve is disposed on the product gas delivery line.
3. The pressure swing adsorption hydrogen purification system of claim 1, wherein a desorption gas programmable valve is arranged on the desorption gas pipeline.
4. The pressure swing adsorption hydrogen purification system of claim 3, wherein the desorption gas line comprises a reverse gas line and a purge line, and the desorption gas programmable valve comprises a reverse gas programmable valve disposed on the reverse gas line and a purge programmable valve disposed on the purge line.
5. The pressure swing adsorption hydrogen purification system of claim 1, wherein the flush inlet line is provided with a flush inlet programmable valve.
6. The pressure swing adsorption hydrogen purification system of claim 1, wherein a downstream programmable valve is provided in the downstream line.
7. The pressure swing adsorption hydrogen purification system of claim 1, wherein a pressure equalization program control valve is provided on the pressure equalization line.
8. The pressure swing adsorption hydrogen purification system of claim 7, wherein the pressure equalization line comprises a fourth pressure equalization/fifth pressure equalization line and a second pressure equalization/third pressure equalization line, and the pressure equalization programmable valve comprises a fourth pressure equalization/fifth pressure equalization programmable valve disposed on the fourth pressure equalization/fifth pressure equalization line and a second pressure equalization/third pressure equalization programmable valve disposed on the second pressure equalization/third pressure equalization line.
9. The pressure swing adsorption hydrogen purification system of claim 1, wherein the first pressure equalization and final pressure boost line is provided with a first pressure equalization and final pressure boost program control valve.
10. The pressure swing adsorption hydrogen purification system of claim 1, wherein the flush inlet line is in communication with the purge inlet line through a flush regulating valve, or wherein the flush inlet line is in communication with the flush inlet line through one or two of the purge buffer tanks and the flush regulating valve.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202120016673.1U CN214087706U (en) | 2021-01-05 | 2021-01-05 | Pressure swing adsorption purification hydrogen system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202120016673.1U CN214087706U (en) | 2021-01-05 | 2021-01-05 | Pressure swing adsorption purification hydrogen system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN214087706U true CN214087706U (en) | 2021-08-31 |
Family
ID=77437727
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202120016673.1U Active CN214087706U (en) | 2021-01-05 | 2021-01-05 | Pressure swing adsorption purification hydrogen system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN214087706U (en) |
-
2021
- 2021-01-05 CN CN202120016673.1U patent/CN214087706U/en active Active
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN100453447C (en) | Technological method of purifying hydrogen of hydrogen enriched gas source | |
| US3430418A (en) | Selective adsorption process | |
| US4790858A (en) | Fractionation of multicomponent gas mixtures by pressure swing adsorption | |
| EP0311932A1 (en) | Recovery of nitrogen, hydrogen and carbon dioxide from hydrocarbon reformate | |
| EP2080735A1 (en) | Hydrogen gas separation method and separation apparatus | |
| US7618478B2 (en) | Process and apparatus to recover medium purity carbon dioxide | |
| KR102481433B1 (en) | Method of Separating and Purifying Hydrogen from Gas Mixture of Ammonia Decompositions | |
| CN101648698A (en) | Preparation method of high purity hydrogen | |
| CN112758892B (en) | Pressure swing adsorption hydrogen purification system and method thereof | |
| KR20120022060A (en) | Method of refining gas and gas refining equipment | |
| CN113350968A (en) | Hydrogen extraction device and process for recovering tail gas components by using synthetic hydrogen | |
| CN101869797A (en) | Method and apparatus for extracting high-purity nitrogen from air | |
| CN110813022A (en) | Multi-bed rapid cycle dynamics PSA | |
| CN111204712B (en) | System for separating and purifying hydrogen by pressure swing adsorption gas and separation and purification method thereof | |
| US20140069275A1 (en) | Low energy cyclic psa process | |
| CN214087706U (en) | Pressure swing adsorption purification hydrogen system | |
| CN110548365A (en) | device and method for preparing high-purity hydrogen from hydrogen-containing gas | |
| CN217939678U (en) | Pressure swing adsorption system for improving separation coefficient | |
| CN217092804U (en) | Pressure swing adsorption hydrogen extraction system in morpholine production process | |
| CN212387734U (en) | Pressure swing adsorption gas separation and purification hydrogen system | |
| CN110550606A (en) | device and method for preparing high-purity hydrogen from hydrogen-containing gas under unsteady state | |
| CN212855191U (en) | Transformation device for purifying hydrogen by pressure swing adsorption | |
| CN217746431U (en) | Low-concentration hydrogen adsorption purification system | |
| KR102439733B1 (en) | Method of Separating and Purifying Deuterium from Gas Mixture of Deuterium and Nitrogen | |
| KR20230106782A (en) | PSA system for efficient separation of impurities from source gas including main gas and impurities, and operating method there of |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |