CN104230621B - A kind of method being produced methane coproduction low-carbon alcohols by carbonaceous material - Google Patents

Abstract

A kind of method being produced methane coproduction low-carbon alcohols by carbonaceous material, the method includes: the crude synthesis gas obtained after being gasified by carbonaceous material carries out purifying to remove the impurity in described crude synthesis gas, obtains clean synthesis gas；At least part of described clean synthesis gas is contacted with mixed catalyst with water, and the product obtained after contact is carried out gas-liquid separation, obtaining gaseous product and product liquid, described mixed catalyst contains water gas shift catalyst and converts synthesis gas to the catalyst of low-carbon alcohols；Being contacted with methanation catalyst by methanation gas raw material, described methanation gas raw material contains described gaseous product, the H in described methanation gas raw material₂The mol ratio of/CO is 2.8 3.5.Methane co-production low-carbon alcohols can be produced according to the method for the present invention, and the load of the hydrosphere transformation during effectively reducing, has saved energy consumption, improve the utilization ratio of carbon, and directly carry out on the methanogenic device of life of prior art, and without increasing equipment.

Description

A kind of method being produced methane coproduction low-carbon alcohols by carbonaceous material

Technical field

A kind of method that the present invention relates to carbonaceous material indirect reformer, in particular, relates to a kind of carbonaceous Material gasification is synthesis gas, and synthesis gas is converted into the method for methane gas co-production low-carbon alcohols.

Background technology

Considering based on energy natural endowment and national energy security, China just actively pushes forward " coal is for oil " strategy, Coal is converted into domestic gas, transportation fuel, basic chemical industry raw material etc..Wherein, coal system is natural Gas technology, is to use low order brown coal through vaporizing system synthesis gas, is then converted to methane, be used as to substitute biography The process of the gaseous fuel of system natural gas.

Natural gas from coal process efficiency is high, water consumes low, technology relative maturity, inclined for exploitation western part of China The coal in remote area, the living standard of the raising people, minimizing dusty gas discharge significant.

The Technical Economy of natural gas from coal technical process is to affect the key factor that this technology is carried out.The U.S. Llanura preparing methane from coal technique, with brown coal as raw material, is 4000kcal/kg at brown coal calorific value, and coal price is 150 During unit/t, adding product conveying and city management expense, methane cost price is at 2.50 yuan/Nm³Left and right, At present, big plain in U.S.A engineering relies primarily on the by-products such as sale ammonia, sulfur, Petroleum, tar, phenols Product reduce the cost of methane, but can not be inherently eliminated economic factor and be stranded enterprise operation Disturb.

Additionally, China's gas is the most unbalanced with gas, northern area gas consumption in winter is big, non-adopts It is few that warm season saves gas, and peaking problem is the most serious.At present, underground natural gas storage tank, gas peak regulation are mainly used The peak regulation means such as generating or LNG, in addition it is also possible to carry out peak regulation with natural gas from coal factory, the most just Shi Shuo natural gas from coal factory winter production natural gas, other seasons can with a part of liquid fuel of coproduction, Chemicals etc..

For solving peaking problem, Dalian Inst of Chemicophysics, Chinese Academy of Sciences proposes a series of for closing Become gas convert produce methane co-production low-carbon alcohols catalyst such as CN102553600A, The disclosed catalyst such as CN102553613A, it is indicated that when these catalyst are used for producing firedamp by syngas Time can coproduction liquid fuel, can according to needs, by regulation reaction condition thus obtain and with methane be Main product or the product based on low-carbon alcohols.Although using this bifunctional catalyst Efficiently solve peaking problem, but before carrying out methanation reaction due to synthesis gas, be both needed to through aqueous vapor Transformationreation regulation H₂/ CO mol ratio, suitably there is methanation reaction, thereby increases energy consumption, has Substantial amounts of CO₂Discharge, reduces the service efficiency of carbon.Additionally, the H needed for synthesis of low-carbon alcohol reaction₂/CO H needed for mol ratio and methanation reaction₂/ CO mol ratio is different, and the most bifunctional catalyst cannot be The H of its optimum₂It is operated under/CO mol ratio operating condition, causes catalyst efficiency relatively low.

Summary of the invention

The invention aims to overcome the above-mentioned deficiency of prior art, it is provided that a kind of energy consumption is low, dioxy Change that carbon emission amount is few and the method being produced methane coproduction low-carbon alcohols by carbonaceous material of simple operation.

The present inventor researchs and analyses discovery, passes through with carbon-rich materials such as coals for raw material and gasifies, only Change the H in the clean synthesis gas obtained₂/ CO mol ratio is relatively low, between 0.5-2.0.And clean synthesis gas system Standby natural gas, it is desirable to the H of clean synthesis gas₂/ CO mol ratio is advisable between 3.0-3.1.Therefore, for adjusting The H of whole clean synthesis gas₂/ CO mol ratio prepares natural gas to be suitable for methanation reaction, and clean synthesis gas is necessary H is carried out through hydrosphere transformation operation₂/ CO mol ratio adjusts, and by H₂/ CO mol ratio is 0.5-2.0's Clean synthesis gas hydrosphere transformation is H₂/ CO mol ratio is in the work of the hydrosphere transformation operation of the gas of 3.0-3.1 Load is very big, and energy consumption is the highest, and economy is low.

And the present inventor studies discovery, synthesis gas prepares the H in the tail gas of low-carbon alcohols₂/ CO mole Than generally greater than material synthesis gas, between 2.0-3.0, and by water gas shift catalyst and by synthesis gas The mixed catalyst obtained after being converted into the catalyst mixing of low-carbon alcohols can realize hydrosphere transformation, can close again The water gas shift catalyst in low-carbon alcohols, i.e. mixed catalyst is become to remain to retain original hydrosphere transformation merit Can, convert synthesis gas to the catalyst of low-carbon alcohols and remain to retain and original convert synthesis gas to low-carbon alcohols Function, substantially disappear without causing the function of single catalyst to have.Therefore, the present inventor Imagination, for carbonaceous material through gasification, purify produce clean synthesis gas, occur methanation reaction it First by clean synthesis gas and water gas shift catalyst and the catalyst converting synthesis gas to low-carbon alcohols before if The mixed catalyst contact obtained after mixing, can not only realize synthesis gas H₂The tune of/CO mol ratio Whole, and a part of low-carbon alcohols can be produced, abundant product category, it is achieved multiple coal base product advantage is mutual Mend, be effectively improved economic benefit and the ability of overall opposing risk of natural gas from coal project.And owing to closing Become the tail gas H compared to material synthesis gas of low-carbon alcohols₂/ CO mol ratio increases, thus compared to existing skill The hydrosphere transformation that directly carried out by whole synthesis gas of art contacts production methane the most again with bifunctional catalyst The method of coproduction low-carbon alcohols, is simultaneously achieved hydrosphere transformation and adjusts H₂/ CO mol ratio and coproduction low-carbon alcohols, So that methanation catalyst is at suitable H₂There is catalytic reaction under/CO mol ratio, improve work effect Rate.

Based on above-mentioned discovery, for realizing the object defined above of the present invention, the invention provides a kind of by carbonaceous material Material produces the method for methane coproduction low-carbon alcohols, and wherein, the method includes: after carbonaceous material is gasified by (1) The crude synthesis gas obtained carries out purifying to remove the impurity in described crude synthesis gas, obtains clean synthesis gas；(2) At least part of described clean synthesis gas is contacted with mixed catalyst with water, and the product obtained after contact is entered Row gas-liquid separation, obtains gaseous product and product liquid, and described mixed catalyst contains water-gas shift catalytic Agent and convert synthesis gas to the catalyst of low-carbon alcohols；(3) under the conditions of methanation reaction, by methanation Gas raw material contacts with methanation catalyst, and described methanation gas raw material contains described gaseous product, institute State the H in methanation gas raw material₂The mol ratio of/CO is 2.8-3.5.

Methane co-production low-carbon alcohols can be produced according to the method for the present invention, and during effectively reducing The load of hydrosphere transformation, saved energy consumption, decreased CO in conversion process₂Generation, improve carbon Utilization rate.Due to its can while coproduction low-carbon alcohols the most energy-conservation so that it will be particularly suitable for The winter of China is big due to heating gas consumption, rather than the national conditions that heating season use gas is few, such as use it for As peak regulation means, compared to traditional for avoiding non-heating season joint natural gas gas low ebb time take directly Traditional vigour peak means of shut-down load down, the method for the present invention will not produce that equipment damage is big, equipment is sharp The defects such as, operation fluctuation low by rate is big.

More specifically, compared with prior art, the beneficial effects are mainly as follows following side Face:

First, the method that the present invention provides, it is possible to realize in same technological process by carbonaceous material warp Cross preparing methane by synthetic gas gas and low-carbon alcohols (generally MAS), enrich natural gas from coal and produce Kind class, can effectively evade the market risk of the single existence of natural gas from coal product, simultaneously can basis Product market demand situation, by regulation process conditions, it is achieved the coproduction of two kinds of products, and can make The two selectivity is adjustable in a big way, and does not affect the steady operating of process units, and low-carbon (LC) mixing Alcohol, no matter as high performance fuel or based on industrial chemicals, all there is wide market, therefore The economic benefit of process can be improved to a certain extent.

Secondly, the method that the present invention provides, hydrosphere transformation can be realized in a reactor and coproduction is low Carbon alcohol, reduces the input of equipment and simplifies operation, and due to coproduction low-carbon alcohols tail gas compared to The H of material synthesis gas₂/ CO ratio is high, and the work thus reducing hydrosphere transformation and de-sour gas operation is born Lotus, is thus advantageous to reduce energy consumption and the CO of technological process₂Discharge, improve the utilization rate of carbon.

3rd, the method that the present invention provides, is to be joined with gaseous products (methane) by MAS Producing, be liquid at normal temperatures and pressures due to MAS, density is big, easily stores, carries out with gas Separate and easily realize, thus this process can be realized without increasing too much separation equipment, additionally throw Provide little.

The method that the present invention provides may be used for various carbonaceous material (include coal but be not limited to coal) The technical process of vaporizing system methane, it is also possible to for having the carbonaceous material of market for natural gas demand through synthesis gas Preparing low-carbon mixed alcohol device improves the utilization of synthesis tail gas.

Detailed description of the invention

The invention provides a kind of method being produced methane coproduction low-carbon alcohols by carbonaceous material, wherein, the party Method includes: the crude synthesis gas that (1) obtains after being gasified by carbonaceous material carries out purifying to remove described thick synthesis Impurity in gas, obtains clean synthesis gas；(2) by least part of described clean synthesis gas and water and mixed catalytic Agent contacts, and the product obtained after contact is carried out gas-liquid separation, obtains gaseous product and product liquid, Described mixed catalyst contains water gas shift catalyst and converts synthesis gas to the catalyst of low-carbon alcohols； (3) under the conditions of methanation reaction, methanation gas raw material is contacted with methanation catalyst, described Methanation gas raw material contains described gaseous product, the H in described methanation gas raw material₂/ CO mole Ratio is 2.8-3.5.

With the method for the invention it is preferred to H in methanation gas raw material₂/ CO mol ratio is 2.9-3.3.

H in the present invention, in the most described methanation gas raw material₂It is 50-99 with the total content of CO Volume %, specifically can be adjusted according to needs.

In the present invention, during specifically used, can be first by water gas shift catalyst with by synthesis gas It is then charged in reactor using as beds after being converted into the catalyst mixing of low-carbon alcohols, it is possible to Water gas shift catalyst and the catalyst converting synthesis gas to low-carbon alcohols are not mixed, and two kinds are urged Agent is each directly layered in proportion or uses as beds in staggered layering loading reactor.

The method according to the invention, mainly includes CO, H in the product after step (2) described contact₂、 CO₂And carbon number less than 5 hydro carbons, carbon number be the low-carbon alcohols of 1-6, unreacted synthesis gas, carbon number Gas hydro carbons less than 5, the carbon number liquid hydrocarbon more than 4, also include other organic oxygen-containing compounds, The byproducts of reaction such as water.

The method according to the invention, step (2) described gaseous product mainly contains CO, H₂、CO₂ And the hydro carbons that carbon number is less than 5, it is the low-carbon alcohols of 1-6, carbon number that described product liquid mainly contains carbon number Hydro carbons, other organic oxygen-containing compounds and water more than 4.

The purpose of the present invention, water in described mixed catalyst can be well realized according to preceding solution Gas transformation catalyst is optional wider range with the content of the catalyst converting synthesis gas to low-carbon alcohols, permissible It is adjusted as required, such as when the less place of methane consumption such as south China or time such as non-heating Typical such as summer in season, when producing methane according to the method for the present invention, owing to methane consumption is few, this Time can increase the content of the catalyst converting synthesis gas to low-carbon alcohols and reduce water gas shift catalyst Content with coproduction low-carbon alcohols as much as possible, thus on the one hand can with coproduction low-carbon alcohols as much as possible, On the other hand, due to the H of tail gas of synthol₂/ CO mol ratio is compared to the H of clean synthesis gas₂/ CO rubs You are more suitable for carrying out methanation reaction by ratio, such that it is able to effectively save energy consumption.For above-mentioned situation, one As described mixed catalyst can contain water gas shift catalyst 60-90 weight %, convert synthesis gas to Catalyst 10-40 weight % of low-carbon alcohols.

And when the place such as northern China or time such as heating season of the methane large usage quantity typical such as winter In season, when producing methane according to the method for the present invention, owing to methane consumption is big, now can reduce step (2) The load of the reaction of middle synthesis of low-carbon alcohol, such as, can reduce the catalyst converting synthesis gas to low-carbon alcohols Content and increase the content of water gas shift catalyst with production methane as much as possible.For above-mentioned feelings Condition, general described mixed catalyst can be containing water gas shift catalyst more than 60 weight %, 90 weights Amount below %, for above-mentioned situation, general described mixed catalyst can be containing water more than 10 weight % Gas transformation catalyst, the catalyst of the synthesis of low-carbon alcohol below 40 weight %.

Based on foregoing description, it is generally preferable in described mixed catalyst water gas shift catalyst with by synthesis gas The weight ratio being converted into low-carbon alcohols is 1-8:1, preferably 2-6:1.Then according to needing within the above range It is adjusted.

Seen from the above description, the method for the present invention can effectively realize coproduction and can use according to methane Amount size, adjusts flexibly, and during be effectively saved energy consumption, reduce CO₂Generation, carry The utilization rate of high-carbon.

The method according to the invention, can be with the use of synthesis gas clean described in set-up procedure (2) according to needs Amount, such as, can contact described for part clean synthesis gas with mixed catalyst with water, and be remained by another part Remaining clean synthesis gas is for other purposes or carries out other process, and makes a living for the main object of the present invention Whole described clean synthesis gas are contacted in preferred steps (2) by methanogenic method with mixed catalyst, Now methanation gas raw material described in step (3) is only containing described gaseous product.

The method according to the invention, in step (2), optional wider range of the condition of described contact, The condition being capable of aforementioned claim all can realize the purpose of the present invention, for the present invention, preferred steps (2) Described in contact condition include: temperature is 150-500 DEG C, and pressure is 0.1-20MPa, gas hourly space velocity For 100-50000h^-1, water is 0.5-1.3:1 with the mol ratio of carbon monoxide.

In the present invention, water and the mol ratio of carbon monoxide refer to water and the rubbing of carbon monoxide in clean synthesis gas You compare.

The method according to the invention, described water gas shift catalyst can be the conventional selection of this area, example As can be the active component element Fe-Cr catalyst that contains Fe and Cr, in described Fe-Cr catalyst Counting the content of active component for 60-95 weight % with oxide, the content of auxiliary agent is 5-40 weight %；Again As being the active component element Cu-Zn catalyst that contains Cu and Zn, described Cu-Zn catalyst In in terms of oxide, the content of active component is 45-90 weight %, and the content of auxiliary agent is 10-55 weight %；Can be and for example the active component element Co--Mo catalyst that contains Co and Mo, described Co-Mo In catalyst in terms of oxide, the content of active component is 60-85 weight %, and the content of auxiliary agent is 15-40 Weight %.Wherein, described adjuvant component can be the conventional selection of this area, and the present invention is not carried out at this Describe in detail.

In the present invention, described in convert synthesis gas to the conventional choosing that the catalyst of low-carbon alcohols can be this area Selecting, such as, can be the active component element Zn-Cr catalyst that contains Zn and Cr, described Zn-Cr urges In agent in terms of oxide, the content of active component is generally 65-95 weight %, and the content of auxiliary agent is general For 5-35 weight %, adjuvant component element can be K, Li, Mg, Mn, Zr, Ce, La, Fe, One or more in Co, Pt and Pd；Can be and for example that active component element contains Cu, Zn and Al Cu-Zn-Al catalyst, in described Cu-Zn-Al catalyst in terms of oxide the content one of active component As be 55-97 weight %, the content of auxiliary agent is generally 3-45 weight %, adjuvant component element can be K, One or more in Li, Fe, Mn, Zr, Ce, La, Ni, Pt, Pd and Rh；Can be and for example Active component element contains the Cu-Co catalyst of Cu and Co, with oxidation in described Cu-Co catalyst Thing meter, the content of active component is generally 50-90 weight %, and the content of auxiliary agent is generally 10-50 weight %, adjuvant component element can be Cr, K, Li, Mn, Fe, Co, U, Rh, Pt, Zr, La With one or more of Nd；Can be such as MoS₂Catalyst, described MoS₂Catalyst refers to molybdenum Oxide through vulcanizing treatment, obtain the solid catalyst that S/Mo atomic ratio is 2；Can also be for living Property component element contains the Zn-Cr catalyst of Zn, Cr, in described Zn-Cr catalyst in terms of oxide, The content of active component is generally 75-99.5 weight %, and the content of auxiliary agent is generally 0.5-25 weight %, Adjuvant component element can be one or more in K, Fe, Li, Al, Mn and La.

The method according to the invention, described methanation reaction condition can be conventional selection, for the present invention, The most described methanation reaction condition includes: pressure is 0.2-5MPa, and temperature is 250-750 DEG C, gas Air speed 100-20000h^-1.The present invention to the reactor of described methanation reaction without particular/special requirement, Ke Yiwei Fixed bed, moving bed or fluid bed, preferably fixed bed or fluid bed.

The method according to the invention, described methanation catalyst can be the conventional selection of this area, wherein, The most described methanation catalyst is loaded catalyst, in described loaded catalyst, and active component unit Element is preferably Ni, carrier is preferably Al₂O₃.Described methanation catalyst can carry out chemical modification, changes Learning the modified adjuvant component element used can be selected from one or more in La, Fe, Mg and Ce.

The method according to the invention, the method for described gas-liquid separation can use the various conventional of prior art Gas-liquid separating method, for the present invention, the method for the most described gas-liquid separation is refrigerated separation, and excellent The temperature selecting described cooling is 5-40 DEG C.

The method according to the invention, the method for described cooling can be direct contact cooling or indirect heat exchange cold But, cooling medium can be water and/or petroleum distillate.

With the method for the invention it is preferred to the method for the present invention also includes: before carrying out step (3), Remove the carbon dioxide in described methanation gas raw material so that the carbon dioxide in methanation gas raw material Content is less than 2.0mol%.The method of carbon dioxide removal is referred to prior art and carries out, and the present invention exists This repeats no more.

The method according to the invention, in described crude synthesis gas, impurity typically contains tar, steam and sulfur-bearing Material etc..

The method according to the invention, the method that the crude synthesis gas obtained after being gasified by carbonaceous material carries out purifying Being referred to prior art carry out, it can select according to the dopant species in crude synthesis gas, as front Impurity in described crude synthesis gas typically contains one or more in tar, steam and sulphur-containing substance, And when the impurity in described crude synthesis gas contains tar, steam and sulphur-containing substance simultaneously, step (1) Middle carbonaceous material is gasified after the crude synthesis gas that the obtains step that carries out purifying generally comprise: by described thick conjunction Become gas to carry out successively cooling down, detar, thick desulfurization, fine de-sulfur, and the clean synthesis gas obtained contain H₂20-40 mole of %, CO15-70 mole of %, CO₂3-35 mole of %, CH₄0-15 mole of %, with And H₂S is less than 0.1 μ g/g.Wherein, described cooling, detar, thick desulfurization, fine de-sulfur method equal Can be the conventional selection of this area, the present invention to this without particular/special requirement.

The method according to the invention, described is conventional selection by the method that carbonaceous material gasifies, and generally comprises: Under the conditions of compressive reaction, being contacted with gasifying agent by carbonaceous material, described gasifying agent is selected from air, oxygen With one or more of steam, preferably oxygen and the gaseous mixture of steam.Described compressive reaction condition Select for routine, generally comprise: temperature 450-2000 DEG C, pressure 0.1-20MPa.And according to needing, Before described carbonaceous material is gasified, described carbonaceous material be dried, pulverize, slurrying, preheating, Melting and wait pretreatment, to this, those skilled in the art all know, and the present invention does not repeats them here.

According to the present invention, described gasification is typically carried out in gasification furnace, and described gasification furnace can be selected fixing The suitable operator schemes such as bed, moving bed, fluid bed, air flow bed, specifically can be according to carbonaceous material Performance selects, and this without particular/special requirement, is not described in detail by the present invention at this.

The method according to the invention, the kind of described carbonaceous material is conventional selection, including, but not limited to Coal, generally low-order coal, preferably brown coal, jet coal, broken coal, fine coal, lump coal, binding coal, One or more in mud coal and water-coal-slurry, for the present invention, the most described carbonaceous material be brown coal and/ Or jet coal.

With the method for the invention it is preferred to the method for the present invention also includes: by step (2) gained liquid Product is separated into the carbon number low-carbon alcohols less than 7, the carbon number liquid hydrocarbon more than 4, water etc..Separating obtained Water contain a certain amount of Organic substance, unit for treating water can be delivered to as sewage and process, so For device or arrange outward afterwards.

With the method for the invention it is preferred to the method for the present invention also includes: step (3) gained is contacted After product carry out cooling down to isolate moisture, obtain gas material, separate described gas material, obtain Gas and periodic off-gases rich in methane.The method according to the invention, the method for described cooling can be straight Connecing contact cooling or indirect heat exchange cooling, cooling medium can be water and/or petroleum distillate.According to the present invention Method, separate the method for described gas material and be referred to prior art and carry out, such as, can be deep cooling Partition method or pressure swing adsorption method.

The method according to the invention, the described gas rich in methane can through mediation after or be sent directly into Pipe network.Described periodic off-gases typically contains low-carbon (LC) hydrocarbons, CO and CO₂In one or more, for Improve the utilization rate of carbon, reduce periodic off-gases and discharge the atmosphere polluting problem caused, described speeding can be put Gas returns step (3) and carries out methanation reaction to recycle, it is also possible to described periodic off-gases is returned step Suddenly (1) carries out gasifying to recycle, or described periodic off-gases is delivered to heating furnace as gas alcohol.

The present invention is described further for the following examples, but not thereby limiting the invention.

Embodiment 1

The present embodiment is for illustrating the side being produced methane coproduction low-carbon alcohols by carbonaceous material that the present invention provides Method.

Brown coal fragment (chemical composition is shown in Table 1) that granular size is 5-50 millimeter are used oxygen/water steam As gasifying agent, gasifying as crude synthesis gas, gained crude synthesis gas sequentially passes through cooling, detar, slightly takes off Clean synthesis gas (composition is shown in Table 2), wherein (CO+H is obtained after sulfur, fine de-sulfur operation₂) content is 63 Volume %, H₂/ CO mol ratio is 1.59；

This clean synthesis gas is divided into G1 and G2 two strands, wherein delivers to G1 close after heat exchange heats up In becoming reactor, with mixed catalyst fixed bed haptoreaction, beds is by water-gas shift catalytic Agent and formate low-carbon alcohol catalyst mix, and the two mass ratio is 3:1, wherein, water-gas shift catalytic Agent is Co--Mo catalyst (producer is Ke Li company, trade names QCS-01), and synthesis of low-carbon alcohol is urged Consisting of of agent: 40 weight %CuO-37 weight %Co₂O₃-21 weight %MnO-2 weight %K₂O； Compound reactor inlet temperature is 228 DEG C, and outlet temperature is 266 DEG C, and pressure is 6.25MPa, gas Air speed is 5000h^-1, reacted product is cooled to 40 DEG C by indirect heat exchange, is divided into gas stream G_aWith liquid stream L_a(part by weight is shown in Table 3), gas stream G_aIn (H₂+ CO) content be 47 The content of volume %, C1-C4 hydrocarbon is 15 volume %, H₂/ CO mol ratio is 2.95, liquid stream L_a The ratio of middle MAS is 78 weight %；

By G_aCO₂It is removed to 1.55 volume %, (H in gas stream₂+ CO) content be 65 bodies Long-pending %, is then heated up by compression further, heat exchange, delivers to methanator, with nickel in terms of element The Ni/Al that content is 15 weight %₂O₃Catalyst haptoreaction, inlet temperature is 304 DEG C, outlet temperature Degree is 461 DEG C, and pressure is 3.18MPa, and gas space velocity is 2500h^-1, the product that reaction obtains is through changing Heat cooling, is cooled to 40 DEG C, isolates aqueous water, and in the gaseous product obtained, the content of methane is 74.3 Volume %.

Embodiment 2

The preparation of clean synthesis gas and form same as in Example 1.All these clean synthesis gas are divided into G1 and G2 two strands.Wherein, G1 delivers in synthesis reactor after heat exchange heats up, solid with mixed catalyst Fixed bed layer haptoreaction, beds is by water gas shift catalyst and formate low-carbon alcohol catalyst mixing Becoming, the two mass ratio is 4:1, and wherein, water gas shift catalyst is that (producer is green grass or young crops to Co--Mo catalyst Island Intertrust, Inc., trade names QDB-03), consisting of of formate low-carbon alcohol catalyst: 50 weight %ZnO-47 weight %Cr₂O₃-3 weight %K₂O；Compound reactor inlet temperature is 305 DEG C, outlet temperature Degree is 342 DEG C, and pressure is 10.33MPa, and gas space velocity is 4500h^-1, reacted product is passed through Indirect heat exchange is cooled to 40 DEG C, is divided into gas stream G_aWith liquid stream L_a(part by weight is shown in Table 3), Gas stream G_aIn (H₂+ CO) content be 56 volume %, the content of C1-C4 hydrocarbon is 13 volume %, H₂/ CO mol ratio is 5.09, liquid stream L_aThe ratio of middle MAS is 92 weight %；

By G2 and G_aMixing, by the CO in gaseous mixture₂It is removed to 1.48 volume %, now (H₂+ CO) Content be 71 volume %, H₂/ CO mol ratio is 3.02, is heated up, so by compression further, heat exchange After deliver to methanator, with the Ni/Al that nickel content in terms of element is 15 weight %₂O₃Catalyst Haptoreaction, inlet temperature is 303 DEG C, and outlet temperature is 449 DEG C, and pressure is 3.94MPa, gas Air speed is 2500h^-1, the product that reaction obtains cools down through heat exchange, is cooled to 40 DEG C and isolates aqueous water, In the gaseous product obtained, the content of methane is 90.2 volume %.

Comparative example 1

The preparation of clean synthesis gas and form same as in Example 1.The clean synthesis gas obtained is fed directly to water Gas converter unit, catalyst is Co--Mo catalyst (producer is Qingdao Intertrust, Inc., trade mark QDB-03), Reactor inlet temperature is 250-260 DEG C, and outlet temperature is 283 DEG C, and water/carbon monoxide mole ratios is 1.3:1, pressure is 3.8MPa, obtains hydrosphere transformation gas.By CO therein₂It is removed to 1.71 volume %, (H₂+ CO) content be 86 volume %, H₂/ CO mol ratio is 3.03, by compressing further, changing Heat heats up, and is then sent to methanator, is 15 weight % with nickel content in terms of element Ni/Al₂O₃Catalyst haptoreaction, inlet temperature is 304 DEG C, and outlet temperature is 461 DEG C, and pressure is 3.03MPa, gas space velocity is 2500h^-1, the product that reaction obtains cools down through heat exchange, is cooled to 40 DEG C Isolating aqueous water, in the gaseous product obtained, the content of methane is 95.3 volume %.

Table 1

Table 2

Clean synthesis gas key component	(mole %)
		H2	38.7
CO	24.3
		CO2	26.5
CH4	8.3
		N2	1.2
AR	0.6
		C2+Hydrocarbon	0.5

Table 3

Note:

(1) total amount of liquid=G1 × L_a/100

(2) total total amount of liquid of gas flow=100%-

(3) total hydrosphere transformation load decrement (Δ WGS in terms of CO2 emissions reduce), is calculated as:

Wherein, $P_t=Y_0/100\×\frac{1}{R_0+1}\×\frac{R_3-R_0}{R_3+1}\×100\%$

Y₀CO+H in unstripped gas gas₂Percentage by volume, %；

R₀H in unstripped gas gas₂/ CO mol ratio；

R₃H in methanation unstrpped gas₂/ CO mol ratio.

(4) CO₂Relative emission changes delta RCE is calculated as:

From embodiment and the result of comparative example, it is compared to comparative example 1, uses the present invention to provide Method, can be by brown coal through clean synthesis gas co-production of methane gas and low-carbon alcohols.Compared to comparative example, press According to embodiment 1, the operational approach of embodiment 2, after reaction end gas is mixed with remaining clean synthesis gas with There is methanation reaction, hydrosphere transformation load can be reduced on the whole and be respectively 17.2%, 17.0%, right CH in production unit volume₄, CO₂Discharge capacity reduce 1.7%, 1.6% respectively.Visible, the present invention Method be capable of the coproduction of methane gas and low-carbon alcohols, not only during total CO₂Discharge capacity subtracts Few, and production unit volume CH₄CO₂Discharge capacity has reduced, and illustrates that the present invention can also be effective Improve the utilization rate of carbon, reduce the discharge of process carbon.

The preferred embodiment of the present invention described in detail above, but, the present invention is not limited to above-mentioned reality Execute the detail in mode, in the technology concept of the present invention, can be to the technical side of the present invention Case carries out multiple simple variant, and these simple variant belong to protection scope of the present invention.

Claims (10)

1. the method being produced methane coproduction low-carbon alcohols by carbonaceous material, it is characterised in that the method Including:

(1) crude synthesis gas obtained after being gasified by carbonaceous material carries out purifying to remove described crude synthesis gas In impurity；

(2) at least part of described clean synthesis gas is contacted with mixed catalyst with water, and will obtain after contact To product carry out gas-liquid separation, obtain gaseous product and product liquid, described mixed catalyst contains water Gas transformation catalyst and the catalyst converting synthesis gas to low-carbon alcohols, in described mixed catalyst, aqueous vapor becomes Catalyst changeout is 1-8:1 with the weight ratio of the catalyst converting synthesis gas to low-carbon alcohols, described low-carbon alcohols It is the low-carbon alcohols of 1-6 for carbon number；

(3) under the conditions of methanation reaction, methanation gas raw material is contacted with methanation catalyst, Described methanation gas raw material contains described gaseous product, the H in described methanation gas raw material₂/ CO's Mol ratio is 2.8-3.5.

Method the most according to claim 1, wherein, described in convert synthesis gas to low-carbon alcohols Catalyst is Zn-Cr catalyst, Cu-Zn-Al catalyst, Cu-Co catalyst and MoS₂In catalyst One or more.

Method the most according to claim 1, wherein, described water gas shift catalyst is Fe-Cr One or more in catalyst, Cu-Zn catalyst and Co--Mo catalyst.

Method the most according to claim 1, wherein, in step (2), by whole described clean conjunctions Gas is become to contact with mixed catalyst；In step (3), described methanation gas raw material is that described gas produces Thing.

Method the most according to claim 1, wherein, in step (2), the condition of described contact Including: temperature is 150-500 DEG C, and pressure is 0.1-20MPa, and gas hourly space velocity is 100-50000h^-1, water It is 0.5-1.3:1 with the mol ratio of carbon monoxide.

Method the most according to claim 1, wherein, in step (2), described gas-liquid separation Method is cooling, and the temperature of described cooling is 5-40 DEG C.

Method the most according to claim 1, wherein, in step (3), described methanation gas H in raw material₂It is 50-99 volume % with the total amount of CO.

Method the most according to claim 1, wherein, in step (3), described methanation reaction Condition includes: pressure is 0.2-5MPa, and temperature is 250-750 DEG C, gas space velocity 100-20000h^-1。

Method the most according to claim 1, wherein, in step (1), gasifies carbonaceous material After the crude synthesis gas that the obtains step that carries out purifying include: carry out described crude synthesis gas successively cooling down, de- Containing H in tar, thick desulfurization and fine de-sulfur, and the clean synthesis gas obtained₂20-40 mole of %, CO 15-70 Mole %, CO₂3-35 mole of %, CH₄0-15 mole of %, and H₂S is less than 0.1 μ g/g.

Method the most according to claim 1, wherein, described carbonaceous material is brown coal and/or length Flame coal.