CN106433827A - Sulfur-containing synthesis gas methanation process - Google Patents
Sulfur-containing synthesis gas methanation process Download PDFInfo
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- CN106433827A CN106433827A CN201610895489.2A CN201610895489A CN106433827A CN 106433827 A CN106433827 A CN 106433827A CN 201610895489 A CN201610895489 A CN 201610895489A CN 106433827 A CN106433827 A CN 106433827A
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- Prior art keywords
- gas
- methanation
- reactor
- catalyst
- sulfur
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- 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
- C10L3/08—Production of synthetic natural gas
Abstract
The invention provides a sulfur-containing synthesis gas methanation process. The process comprises the steps that the mixed feed gas is formed by synthesis gas and water vapor and is divided into three parts; the first mixed feed gas enters a first reactor filled with a molybdenum-based catalyst from the top end, the heat of the outlet gas is recovered and the outlet gas is cooled; the second mixed feed gas and the outlet gas of the first reactor enter a second reactor filled with the molybdenum-based catalyst from the top end together, the heat of the outlet gas is recovered and the outlet gas is cooled; the third mixed feed gas and the outlet gas of the second reactor enter a third reactor filled with the molybdenum-based catalyst from the top end together, the outlet gas is cooled by a heat exchanger and then the condensed water is removed by a gas-liquid separator, thus obtaining the product gas. The process has the advantages of no need for gas cycle, low energy consumption, easiness in operation and low equipment investment.
Description
Technical field
The invention belongs to a kind of synthesis gas methanation process is and in particular to a kind of sulfur-bearing synthesis gas carries out the work of methanation
Skill.
Background technology
Methane is a kind of important fuel and chemical intermediate, can be used for the conjunction of the multiple compounds such as ethylene, acetylene, formaldehyde
Become.In recent years, increasing sharply with China's natural gas demand, the insufficiency of supply-demand of domestic natural gas resource is gradually increased.With
Producing synthesis gas from coal is raw material, and is to improve domestic natural gas to supply the effective of situation by methanation reaction production substitute natural gas
Approach.Methanation is the core technology of natural gas from coal, and this reaction refers to CO or CO2Hydrogenation synthesis CH in the presence of catalyst4
And H2O, reaction equation is as follows：
CO+3H2=CH4+H2O+206KJ/mol (1)
CO2+4H2=CH4+2H2O+165KJ/mol (2)
At present, main natural gas from coal technology all adopts fixed bed methanation process in the world, and catalyst is support type Ni
Base catalyst.However, Ni base catalyst is easy to sulfur poisoning inactivation, need to add desulfurization before methanation process flow process
Link.This process often adopts low-temp methanol washing process, but this technique needs substantial amounts of methanol solvate sub-cooled, energy consumption
Higher, improve the process energy consumption of overall process.Desulfurization work need not be carried out before methanation process using methanation in presence of sulfur technique
Skill, can greatly reduce process energy consumption and producing cost, reduce sweetening process gas treatment amount, save equipment investment.
Patent CN104388139A discloses a kind of method and system of raw gas direct methanation, synthesis gas in this invention
Through the pre-heat treatment, pre- methanation reaction, transformationreation, methanation reaction, desulfurization and 5 main technique links of carbonization treatment,
Effectively reduce desulfurization link gas treatment amount.But during being somebody's turn to do also there is gas circulation in methane pretreatment link, increases
During energy consumption, simultaneously non-processed gas be directly entered full methanation reaction link, easily cause catalyst sulfur poisoning at this.
Patent CN104152199A discloses a kind of producing synthesis gas from coal and carries out the technique that methanation in presence of sulfur prepares natural gas, should
Technique, with raw gas as raw material, carries out portion of methane initially with 2 sections of bed series connection, subsequently carries out low temperature methanation desulfurization and take off
Carbon, then carry out full methanation.But the setting of reactors in series increases reaction system pressure drop, it is unfavorable for synthesizing gas disposal energy
The increase further of power.
Content of the invention
It is an object of the present invention to provide one kind circulates without gas, the sulfur-bearing synthesis gas that energy consumption is low, easy to operate, equipment investment is low
The technique carrying out methanation.
The present invention to achieve the above object of the invention, employs 3 grades of insulation fix bed reactors, setting by process route
Meter, the optimization of the setting of reaction unit, catalyst composition and type of feed, can carry out part first to the synthesis gas without desulfurization
Alkanisation, is substantially reduced reaction gas volume, thus reducing sulfur removal technology process gas treating capacity thereafter, reaching reduction sulfur removal technology and setting
Standby scale and the purpose reducing process energy consumption.Meanwhile, portion of methane process circulates without gas it is also possible to reduce corresponding gas
Body circulation power load and energy consumption.
The technical solution used in the present invention and concrete technology are：
(1) respectively catalyst with base of molybdenum is loaded into three methanation catalysts R1, R2, R3, carries out first vulcanizing pre- place
Reason, then carries out methanation reaction；
(2) synthesis gas and vapor mixing composition mixed material gas, mixed material gas is divided into Part I through preheating to be mixed
Close unstripped gas, Part II mixed material gas and Part III mixed material gas；
(3) Part I mixed material gas enters equipped with catalyst with base of molybdenum the first methanator R1 from top, exports
Gas reclaims heat by primary waste heat boiler and carries out gas cooling；
(4) enter equipped with molybdenum from top together with the working off one's feeling vent one's spleen of Part II mixed material gas and the first methanator R1
In base catalyst the second methanator R2, work off one's feeling vent one's spleen and heat is reclaimed by the second heat boiler and carries out gas cooling；
(5) enter equipped with molybdenum from top together with the working off one's feeling vent one's spleen of Part III mixed material gas and the second methanator R2
In base catalyst front three alkylation reactors R3, work off one's feeling vent one's spleen through heat exchanger cooling, subsequently condensation is removed by gas-liquid separator
Water and low-temp methanol are washed, and obtain product gas.
Synthesis gas as above is prepared through gasification and water-gas shift process for coal.
Reactor R1, R2, R3 inlet temperature as above control respectively 280～340 DEG C, 290～350 DEG C, 300～
360 DEG C, outlet temperature is respectively at 600～640 DEG C, 550～600 DEG C, 450～500 DEG C.On the basis of reactor R1, gas
Volume space velocity is 10000～150000L kg-1·h-1, inlet pressure is 1～5MPa.
Synthesis gas as above is 0.46～1.46 with the mol ratio of vapor:1.
In synthesis gas as above, H:Cmoleratio controls in (H2-CO2)/(CO+CO2)=3.0～3.5:1.
Capacity distribution ratio in reactor R1, R2, R3 for the mixed material gas as above is respectively adopted following ratio,
R1：R2=1:1.0～0.5, R1：R3=1:0.8～0.3.
Catalyst with base of molybdenum is adopted in reactor R1, R2, R3 as above, consisting of active component molybdenum oxide and carrier
Aluminium oxide.In catalyst in wherein reactor R1, molybdenum mass percent is 10%～15%.Catalyst molybdenum quality in reactor R2
Percentage ratio is 20%～35%.In reactor R3, catalyst molybdenum mass percent is 30～60%.
Catalyst with base of molybdenum as above adopts infusion process to prepare.Its preparation process is as follows：Compound concentration be 0.5～
The ammonium molybdate solution of 1.3g/ml, is added thereto to the γ-Al of 10～40 mesh2O3Support powder, under agitation dipping 12～
24h, suspension is heated concentration under 60～90 DEG C of water bath condition by dipping after terminating, subsequently 550～650 DEG C of roastings 6～
12h, is ground to 10～40 mesh after roasting.
Molybdenum element in catalyst with base of molybdenum as above is molybdenum oxide form, needs to be vulcanized after loading in the reactor
Pretreatment.Pretreatment temperature is 400～500 DEG C, H in pretreatment gas2S volume consists of 2～5%, and remaining is H2, pretreatment
Time is 12～48h, and pretreatment gas air speed is 1000～5000L kg-1·h-1, pressure is 2～4MPa.
Reactor R1 beds ratio of height to diameter as above is 1：1.5～2.0, reactor R2 catalyst bed floor height footpath
Than for 1：The beds ratio of height to diameter of 0.8～1.2, reactor R3 is 1:0.4～0.8.
Catalyst and quartz sand mixed packing is adopted in reactor R1, R2, R3 as above.Urge in wherein reactor R1
Agent and quartz sand filling mass ratio are 1:In 0.8～1.2, R2, catalyst and quartz sand filling mass ratio are 1:0.4～0.8,
In R3, catalyst and quartz sand filling mass ratio are 1:0.2～0.5.
Reactor catalyst as above loads mass ratio, R1：R2=1:0.5～1.5, R1：R3=1:0.5～
1.5.
The present invention compared with prior art, has substantive distinguishing features and marked improvement is：
(1) course of reaction circulates without gas, and the equipment not only decreasing high-power compressor and its auxiliary facility etc. is thrown
Money, simplifies technical process, and decreases and repeatedly cool down and the heating energy expenditure of link and power consumption needed for compressed action.
(2) methanation high temperature gas has carried out heat exchange by waste heat boiler and heat exchanger, to exothermic heat of reaction
Carry out effective management, and reasonable utilization has been carried out to heat.
(3) process, using the synthesis gas without desulfurization as raw material, significantly reduces the gas treatment amount of sweetening process thereafter,
Greatly save relevant device investment and process energy consumption.
Brief description
Fig. 1 is the process chart of the present invention.
As shown in figure 1,1 is heat exchanger, 2,3 is waste heat boiler, and 4 is cooler, and 5 is gas-liquid separator, and R1, R2, R3 are
Fixed bed methanator, P1, P2, P3, P4, P5, P6 are pipelines.
Specific embodiment
Below by specific embodiment, the specific embodiment of the present invention is further described in detail.
Embodiment 1
In reactor R1, the catalyst preparation conditions of filling are：Compound concentration is the ammonium molybdate solution of 0.5g/ml, thereto
Add the γ-Al of 10～40 mesh2O3Support powder, impregnates 12h under agitation, impregnates suspension after terminating in 60 DEG C of water
Under the conditions of bath, heating concentrates, and subsequently in 550 DEG C of roasting 6h, is ground to 10～40 mesh after roasting.Filling in reactor R2 and R3
Catalyst preparation conditions see attached list 2.
Carry out after Catalyst packing vulcanizing pretreatment, pretreatment temperature is 400 DEG C, H in pretreatment gas2S volume forms
For 2%, remaining is H2, pretreatment time is 12h, and pretreatment gas air speed is 1000L kg-1·h-1, pressure is 2MPa.
In course of reaction, coal produces coal gas through gasification, then passes through water gas shift reation and adjusts hydrogen-carbon ratio, becomes resistant to sulfur
The raw material of portion of methaneization reaction, this synthesis gas consists of (vol%)：H2：67.9, CO：18.1, CO2：1.0, CH4：12.0,
N2：1.0, gas hydrogen-carbon ratio is 3.5:1.Synthesis gas passes through P1 pipeline, (is 1 with synthesis gas mol ratio with steam:0.66) mix
Heated by heat exchanger afterwards, the gas wherein accounting for cumulative volume 37% enters the first fixed bed reactors R1, reaction by pipeline P2
Gas is entered after waste heat boiler 2 is cooled down and is conveyed by pipeline P3 afterwards, the raw material accounting for cumulative volume 37% with P4 pipeline
The second fixed bed reactors R2 is entered, after gas entrance waste heat boiler 3 is cooled down after reaction, with P5 pipeline after gas mixing
Account for cumulative volume 26% unstripped gas mixing after enter the 3rd fixed bed reactors R3.Gas subsequently passes through pipeline P6 and enters cooling
Device 4, enters back into gas-liquid separator 5 removing condensed water and obtains dry reaction gas, consisting of (vol%)：H2- 11.4, CO-3.3,
CO2- 7.4, CH4- 73.2, N2-4.7.Gas then passes through low-temp methanol and washes, and eventually becomes synthetic natural gas product.
This process specific process parameter sees attached list 1, and the catalyst preparation conditions that reaction adopts see attached list 2, vulcanizes pretreatment
Condition sees attached list 3, and unstripped gas and product gas composition see attached list 4.
Embodiment 2～11
On the basis of embodiment 1,2～11 pairs of reaction pressures of embodiment, air speed, reactor catalyst bed ratio of height to diameter,
Each reactor catalyst loads mass ratio, synthesis gas hydrogen-carbon ratio, synthesis gas and vapor mol ratio, unstripped gas allocation proportion, urges
Agent molybdenum component content, catalyst and quartz sand mass ratio, reactor inlet temperature, reactor outlet temperature are adjusted,
Concrete data and result see attached list 1, and the catalyst preparation conditions that reaction adopts see attached list 2, and sulfuration pretreatment condition sees attached list 3,
Unstripped gas and product gas composition see attached list 4.Remaining is with embodiment 1.
Subordinate list 3
Subordinate list 4
Claims (11)
1. a kind of sulfur-bearing synthesis gas carries out the technique of methanation it is characterised in that comprising the steps：
（1）Respectively catalyst with base of molybdenum is loaded into three methanation catalysts R1, R2, R3, carries out first vulcanizing pretreatment, so
After carry out methanation reaction；
（2）Synthesis gas and vapor mixing composition mixed material gas, it is former that mixed material gas is divided into Part I mixing through preheating
Material gas, Part II mixed material gas and Part III mixed material gas；
（3）Part I mixed material gas enters equipped with catalyst with base of molybdenum the first methanator R1 from top, works off one's feeling vent one's spleen logical
Cross primary waste heat boiler to reclaim heat and carry out gas cooling；
（4）Enter from top together with the working off one's feeling vent one's spleen of Part II mixed material gas and the first methanator R1 and urge equipped with molybdenio
In agent the second methanator R2, work off one's feeling vent one's spleen and heat is reclaimed by the second heat boiler and carries out gas cooling；
（5）Enter from top together with the working off one's feeling vent one's spleen of Part III mixed material gas and the second methanator R2 and urge equipped with molybdenio
In agent front three alkylation reactors R3, work off one's feeling vent one's spleen through heat exchanger cooling, subsequently by gas-liquid separator remove condensed water with
Low-temp methanol is washed, and obtains product gas.
2. a kind of sulfur-bearing synthesis gas carries out the technique of methanation it is characterised in that described reactor as claimed in claim 1
R1, R2, R3 inlet temperature controls at 280 ~ 340 DEG C, 290 ~ 350 DEG C, 300 ~ 360 DEG C respectively, and outlet temperature is respectively at 600 ~
640 DEG C, 550 ~ 600 DEG C, 450 ~ 500 DEG C, on the basis of reactor R1, gas volume air speed is 10000 ~ 150000L kg-1·
h-1, inlet pressure is 1 ~ 5MPa.
3. a kind of sulfur-bearing synthesis gas carries out the technique of methanation it is characterised in that described synthesis gas as claimed in claim 1
Mol ratio with vapor is 0.46 ~ 1.46:1.
4. a kind of sulfur-bearing synthesis gas carries out the technique of methanation it is characterised in that described synthesis gas as claimed in claim 1
Middle H:Cmoleratio controls（H2-CO2）/（CO+CO2）=3.0~3.5:1.
5. a kind of sulfur-bearing synthesis gas carries out the technique of methanation it is characterised in that described mixing is former as claimed in claim 1
Material capacity distribution ratio in reactor R1, R2, R3 for the gas is respectively R1：R2=1:1.0 ~ 0.5, R1：R3=1:0.8~0.3.
6. a kind of sulfur-bearing synthesis gas carries out the technique of methanation it is characterised in that described reactor as claimed in claim 1
Catalyst with base of molybdenum is adopted, consisting of urging in active component molybdenum oxide and alumina catalyst support, wherein reactor R1 in R1, R2, R3
In agent, molybdenum mass percent is 10% ~ 15%；In reactor R2, catalyst molybdenum mass percent is 20% ~ 35%；In reactor R3
Catalyst molybdenum mass percent is 30 ~ 60%.
7. a kind of sulfur-bearing synthesis gas carries out the technique of methanation it is characterised in that described molybdenio is urged as claimed in claim 6
Agent adopts infusion process to prepare, and its preparation process is as follows：Compound concentration is the ammonium molybdate solution of 0.5～1.3g/ml, thereto plus
Enter the γ-Al of 10 ~ 40 mesh2O3Support powder, impregnates 12 ~ 24h under agitation, impregnates suspension after terminating in 60 ~ 90 DEG C
Under water bath condition, heating concentrates, and subsequently in 550 ~ 650 DEG C of roasting 6 ~ 12h, is ground to 10 ~ 40 mesh after roasting.
8. a kind of sulfur-bearing synthesis gas carries out the technique of methanation it is characterised in that described sulfuration is pre- as claimed in claim 1
Process is pretreatment temperature is 400 ~ 500 DEG C, H in pretreatment gas2S volume consists of 2 ~ 5%, and remaining is H2, pretreatment time
For 12 ~ 48h, pretreatment gas air speed is 1000 ~ 5000L kg-1·h-1, pressure is 2 ~ 4MPa.
9. a kind of sulfur-bearing synthesis gas carries out the technique of methanation it is characterised in that described reactor as claimed in claim 1
R1 beds ratio of height to diameter is 1：1.5 ~ 2.0, reactor R2 beds ratio of height to diameter is 1：0.8 ~ 1.2, reactor R3's
Beds ratio of height to diameter is 1:0.4~0.8.
10. a kind of sulfur-bearing synthesis gas carries out the technique of methanation it is characterised in that described reactor as claimed in claim 1
Catalyst and quartz sand mixed packing is adopted, in wherein reactor R1, catalyst and quartz sand filling mass ratio are in R1, R2, R3
1:In 0.8 ~ 1.2, R2, catalyst and quartz sand filling mass ratio are 1:Catalyst and quartz sand filling quality in 0.4 ~ 0.8, R3
Than for 1:0.2~0.5.
11. as claimed in claim 1 a kind of sulfur-bearing synthesis gas carry out the technique of methanation it is characterised in that described reactor
Catalyst packing mass ratio is, R1：R2=1:0.5 ~ 1.5, R1：R3=1:0.5~1.5.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610562874 | 2016-07-18 | ||
| CN2016105628745 | 2016-07-18 |
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| Publication Number | Publication Date |
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| CN106433827A true CN106433827A (en) | 2017-02-22 |
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| CN201610895489.2A Pending CN106433827A (en) | 2016-07-18 | 2016-10-13 | Sulfur-containing synthesis gas methanation process |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109810739A (en) * | 2019-03-01 | 2019-05-28 | 新地能源工程技术有限公司 | A kind of resistant to sulfur process for synthesizing methane and device |
| CN110243992A (en) * | 2018-03-09 | 2019-09-17 | 国家能源投资集团有限责任公司 | The preparation method and Catalyst evaluation test system of evaluating catalyst unstripped gas |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4064156A (en) * | 1977-02-02 | 1977-12-20 | Union Carbide Corporation | Methanation of overshifted feed |
| CN1957076A (en) * | 2004-04-06 | 2007-05-02 | 燃料电池能有限公司 | Methanation device using multiple reactors |
| CN101560423A (en) * | 2008-04-16 | 2009-10-21 | 卡萨尔甲醇公司 | Process and plant for substitute natural gas |
| CN105255532A (en) * | 2015-11-06 | 2016-01-20 | 中国海洋石油总公司 | Fluidized bed and fixed bed combined methanation method |
-
2016
- 2016-10-13 CN CN201610895489.2A patent/CN106433827A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4064156A (en) * | 1977-02-02 | 1977-12-20 | Union Carbide Corporation | Methanation of overshifted feed |
| CN1957076A (en) * | 2004-04-06 | 2007-05-02 | 燃料电池能有限公司 | Methanation device using multiple reactors |
| CN101560423A (en) * | 2008-04-16 | 2009-10-21 | 卡萨尔甲醇公司 | Process and plant for substitute natural gas |
| CN105255532A (en) * | 2015-11-06 | 2016-01-20 | 中国海洋石油总公司 | Fluidized bed and fixed bed combined methanation method |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110243992A (en) * | 2018-03-09 | 2019-09-17 | 国家能源投资集团有限责任公司 | The preparation method and Catalyst evaluation test system of evaluating catalyst unstripped gas |
| CN109810739A (en) * | 2019-03-01 | 2019-05-28 | 新地能源工程技术有限公司 | A kind of resistant to sulfur process for synthesizing methane and device |
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