CN1702039A - Process for preparing CO and synthetic gas and methanol by steam combination conversion of hydrocarbons - Google Patents

Abstract

The invention relates to a method of built-up hydrocarbon steam conversion to produce CO, synthetic gas and methanol. The invention adopts two series. In one of the series, second reformed gas is separated with part CO and residue gas is mixed with second reformed gas generated in the other series to produce synthetic gas. Said CO is used to compound acetate by carbonylation of methanol and synthetic gas is used in methanol synthesis. High-heat second reformed gas from second converter is used to heat logistics in heat-exchanger type first converter tube, so the invention saves consumption of fuel gas greatly. The invention can realize cogeneration of methanol and acetic acid and cycle natural gas sauce to be used.

Description

A kind of hydrocarbon vapours built-up type transforms the method for preparing CO and synthetic gas and methyl alcohol

Technical field

The present invention relates to a kind of hydrocarbon vapours built-up type and transform the method for preparing CO and synthetic gas and methyl alcohol.

Background technology

Adopting hydrocarbon gas is the feedstock production ammonia-synthesizing material gas, industrialized the earliest technological process is the normal pressure partial oxidation, development along with the metallurgical technology technology, the processing and fabricating of high temperature alloy conversion tube (as HK-40, HP-Nb) has obtained solution, and hydrocarbon gas steam under pressure conversion process has just replaced the normal pressure partial oxidation technology.Up to now, transfer pressure is brought up to 3.0～4.3MPa from normal pressure, and industrial scale also maximizes day by day, and single series synthetic ammonia maximum-norm is 1700MTPD in the world today, and single series methyl alcohol maximum-norm is more than the 2540MTPD.Tradition synthesis gas preparation technology, no matter be the normal pressure partial oxidation process, the continuous conversion process that perhaps pressurizes all be two sections reforming gas of high temperature directly to be imported waste heat boiler produce high-parameters steam, and the required heat of hydrocarbon gas steam reforming has to solve by a part of hydrocarbons that burns.

The core of energy-saving technique is exactly to reduce the consumption of burning with hydrocarbons as far as possible, thereby realize the autothermal balance or the half autothermal balance (the former transforms two sections conversion process of string oxygen-rich air for a section as LCA technology and heat exchange, the latter such as hydrocarbon vapours heat exchange type series connection conversion process and this technology) of conversion process process.

For autothermal balance or the half autothermal balance that realizes conversion process, just set about developing heat exchange type abroad since the eighties in last century and transform gas-making process.Realizing industrialized the earliest is the LCA technology of Britain I.C.I company, and its industrial scale is 300～450MTPD.This process using heat-exchanged reformer replaces traditional external-heat one-stage converter, and with the portion C H of one-stage converter ₄The steam reforming load is shifted to secondary reformer, in secondary reformer, add excess air, to keep the autothermal balance of system, be used to simultaneously carry out heat exchange outside the heat exchange type primary reformer tubes and between the inner reaction tube thing, so that the required heat of hydrocarbons steam reforming reaction in the pipe to be provided from two sections reforming gas of high temperature of secondary reformer.In order to satisfy ammonia synthesis reaction to H in the unstripped gas ₂/ N ₂Requirement, be provided with the PSA device, removing the excess nitrogen of the system that brings into excess air, also remove CO simultaneously ₂Gas.LCA technology is removing excessive N ₂Process in, caused certain amount of H ₂Loss, in order to overcome this shortcoming, lattice sieve De-Nol nitrogen synthesis of Byelorussia adopts two sections conversion process of string oxygen-rich air behind the heat exchange type one-stage converter, thereby has both reached system's autothermal equilibrated purpose, does not have H again ₂The loss problem just need be provided with cover PSA air separation (or empty branch) device in addition.

In last century end, I.C.I has succeeded in developing the LCM technology that is used to produce methyl methanol syngas on LCA technology basis, promptly uses to add pure oxygen to replace excess air in secondary reformer.Meanwhile, also succeed in developing the heat exchange type oxygen-rich air at home in succession and transformed the system ammonia-synthesizing material gas, the heat-exchanging type parallel conversion is connected with heat exchange type and is transformed preparation ammonia synthesis gas technology, and heat exchange type pure oxygen two sections conversion process system methyl alcohol synthetic raw gas and two sections conversion systems of heat-exchanging type parallel conversion string pure oxygen methyl alcohol synthetic raw gas.

But all exist natural gas source not to be fully used in the above technology, methanol production and carbonylation of methanol acetic acid production can not be united and carry out, the shortcoming of a large amount of combustion fuel gas, and can not fundamentally solve hydrogen and the unbalanced problem of carbon.

Summary of the invention

Main purpose of the present invention is to make full use of natural gas source, methanol production and carbonylation of methanol acetic acid production can be united and carry out, fundamentally solve the unbalanced problem of hydrogen and carbon, and can realize the resources circulation use, reduce fuel gas consumption, energy-saving and cost-reducing, minimizing is invested and the reduction of erection time.

In order to achieve the above object, the invention provides a kind of hydrocarbon vapours built-up type and transform the method for preparing CO and synthetic gas, the unstripped gas that contains hydrocarbons that this method adopts is Sweet natural gas, liquefied petroleum gas (LPG) or coal mine gas, and its technological process is as follows:

1), adopt A, two series of B, in the A series, an external-heat one-stage converter that enters respectively after the unstripped gas of hydrocarbon-containifirst material and the vapor mixing and a heat exchange type one-stage converter, described external-heat one-stage converter and heat exchange type one-stage converter are finished one section steam reforming reaction of hydrocarbons jointly, steam reforming reaction institute heat requirement is from the high level heat of two sections reforming gas of high temperature of secondary reformer generation in the described heat exchange type one-stage converter, this heat obtains by the indirect heat exchange between two sections reforming gas of described high temperature and the described heat exchange type one-stage converter inner reaction tube thing, described external-heat one-stage converter is chewed combustion fuel gas by burning, for the hydrocarbon steam conversion reaction provides heat, enter described secondary reformer after one section reforming gas that reaction generates in described heat exchange type one-stage converter and the external-heat one-stage converter mixes and carry out CH ₄Degree of depth conversion reaction; In the B series, the unstripped gas of hydrocarbon-containifirst material and vapor mixing are after after the import/export interchanger preheating, enter a heat exchange type one-stage converter and carry out one section steam reforming reaction, steam reforming reaction institute heat requirement is from the high level heat of two sections reforming gas of high temperature of secondary reformer generation in the described heat exchange type one-stage converter, this heat obtains by the indirect heat exchange between two sections reforming gas of described high temperature and the described heat exchange type one-stage converter inner reaction tube thing, and one section reforming gas that reaction generates in the described heat exchange type one-stage converter enters described secondary reformer and carries out CH ₄Degree of depth conversion reaction; Two secondary reformers in described A, B two series add CO respectively ₂Gas is in order to regulate the H of the two sections reforming gas of high temperature that generate ₂/ C ratio, or add pure oxygen in two secondary reformers in described A, B two series, in order to keep minimum N in two sections reforming gas of system's thermal equilibrium and high temperature ₂Content, or add the unstripped gas contain hydrocarbons in two secondary reformers in described A, B two series is in order to the content that increases CO in two sections reforming gas of high temperature and can be energy-conservation;

2), after two sections reforming gas of high temperature of generating of the secondary reformer described in the B series offer described heat exchange type one-stage converter with heat, after reducing temperature, heat recovery equipment enters the CO tripping device again, cutting out partial CO; After two sections reforming gas of high temperature that secondary reformer described in the A series generates offer described heat exchange type one-stage converter with heat, through heat recovery equipment, mixes with the tail gas behind two sections reforming gas separate part CO of the described secondary reformer of B series, be used as synthetic gas.

The unstripped gas described in two series of A, B is separate in the aforesaid method, the mol ratio of total carbon is 1.8～4.5 for A series in steam and the raw material hydrocarbon, for B series is 1.0～4, the pressure that enters the gas mixture of interior unstripped gas of heat exchange type primary reformer tubes described in heat exchange type one-stage converter described in the A series and described external-heat one-stage converter and the B series and steam is 0.2～4MPa, and temperature is 400～600 ℃; The temperature of one section reforming gas in the exit of heat exchange type one-stage converter is 500～750 ℃ described in heat exchange type one-stage converter described in the A series and the B series, CH ₄Butt volume ratio therein is 12～26%; The temperature of one of the exit of external-heat primary reformer tubes section reforming gas is 700～800 ℃ described in the A series, CH ₄Butt volume ratio therein is 3～12%; The temperature of two sections reforming gas in the exit of secondary reformer is 800～1050 ℃ described in secondary reformer described in the A series and the B series.

The CO that in described secondary reformer, adds in the A series in the aforesaid method ₂Mole number be 0～25% of A series raw material gas total carbon mole number, the CO that in described secondary reformer, adds in the B series ₂Mole number be unstripped gas total carbon mole number 0～45%; The mole number of the unstripped gas of the hydrocarbon-containifirst material that adds in described secondary reformer in the A series is 0～28% of an A series raw material gas total carbon mole number, and the mole number of the unstripped gas of the hydrocarbon-containifirst material that adds in described secondary reformer in the B series is 0～35% of a unstripped gas total carbon mole number; The pure oxygen amount that adds in described secondary reformer in the B series is wanted to keep system's thermal equilibrium, and is guaranteed CH in its two sections reforming gas ₄The butt volume ratio be 2～0.3%.

CO in the aforesaid method described in the step 1) ₂Be from the combustion product gases of external-heat one-stage converter described in the A series, to reclaim.Described combustion product gases is reclaiming CO ₂Before, the CO that is provided with the convection zone of described external-heat one-stage converter ₂Preheat coil, hydro carbons gas/steam preheating coil pipe, hydro carbons gas preheat coil, oxygen preheat coil pipe and the heat exchange of combustion air preheat coil after self temperature reduces, just enter stack gas recovery CO ₂Device.

The gas composition that above-mentioned preparation method obtains synthetic gas can meet the following conditions, and can be used for the low pressure methanol synthesis technique:

$f=\frac{H_2-{\mathrm{CO}}_2}{\mathrm{CO}+{\mathrm{CO}}_2}$ $=2.05~2.15$

In the formula: f-ratio, no unit,

H ₂The molar flow of-hydrogen, kmol/h,

CO ₂The molar flow of-carbonic acid gas, kmol/h,

The molar flow of CO-carbon monoxide, kmol/h.

The CO that above-mentioned preparation method prepares can be used as the methanol carbonyl synthesized acetic acid unstripped gas, and the synthetic gas of acquisition can be used as the methyl alcohol synthetic raw gas.

The present invention also provides a kind of method of utilizing synthesis gas preparation methyl alcohol, the H that the off-gas that produces in the described synthesis gas preparation methanol process obtains through separation ₂, rich CO ₂Gas and tail gas turn back to again in the synthesis gas preparation process, realize resource circulation utilization.The technological process of this method is as follows:

1), adopt two series of A, B, in the A series, the off-gas that produces in the unstripped gas of hydrocarbon-containifirst material and the methyl alcohol building-up process is through separating the H that obtains ₂After the mixing again with vapor mixing after the external-heat one-stage converter and the heat exchange type one-stage converter that enter respectively, described external-heat one-stage converter and heat exchange type one-stage converter are finished one section steam reforming reaction of hydrocarbons jointly, steam reforming reaction institute heat requirement is from the high level heat of two sections reforming gas of high temperature of secondary reformer generation in the described heat exchange type one-stage converter, this heat obtains by the indirect heat exchange between two sections reforming gas of described high temperature and the described heat exchange type one-stage converter inner reaction tube thing, described external-heat one-stage converter is chewed combustion fuel gas by burning and is provided heat for hydrocarbon steam conversion reaction, the part of described fuel gas from the off-gas that produces in the methyl alcohol building-up process through separating H ₂And CO ₂After tail gas; Enter described secondary reformer after one section reforming gas that reaction generates in described heat exchange type one-stage converter and the external-heat one-stage converter mixes and carry out CH ₄Degree of depth conversion reaction; In the B series, the unstripped gas of hydrocarbon-containifirst material and vapor mixing are after after the import/export interchanger preheating, enter a heat exchange type one-stage converter and carry out one section steam reforming reaction, steam reforming reaction institute heat requirement is from the high level heat of two sections reforming gas of high temperature of secondary reformer generation in the described heat exchange type one-stage converter, this heat obtains by the indirect heat exchange between two sections reforming gas of described high temperature and the described heat exchange type one-stage converter inner reaction tube thing, and one section reforming gas that reaction generates in the described heat exchange type one-stage converter enters described secondary reformer and carries out CH ₄Degree of depth conversion reaction; Secondary reformer in described A, B two series adds the CO that the off-gas that produces in the methyl alcohol building-up process obtains through separation respectively ₂Gas is in order to regulate the H of the two sections reforming gas of high temperature that generate ₂/ C ratio, or add pure oxygen in the secondary reformer in described A, B two series, in order to keep minimum N in two sections reforming gas of system's thermal equilibrium and high temperature ₂Content, or add the unstripped gas contain hydrocarbons in the secondary reformer in described A, B two series is in order to the content that increases CO in two sections reforming gas of high temperature and can be energy-conservation;

2), after two sections reforming gas of high temperature of generating of the secondary reformer described in the B series offer described heat exchange type one-stage converter with heat, after reducing temperature, heat recovery equipment enters the CO tripping device again, cutting out partial CO; After two sections reforming gas of high temperature that secondary reformer described in the A series generates offer described heat exchange type one-stage converter with heat, through heat recovery equipment, mixes with the tail gas behind two sections reforming gas separate part CO of the described secondary reformer of B series, be used as synthetic gas.

The adoptable device (or method) of separation of C O that is used for from cooled second stage exit gas comprises that PSA separates adsorption unit among the above-mentioned preparation method, and Deep Cooling Method separation of C O, or complexed absorption separation of C O recommend to use PSA to separate adsorption unit.

Among this preparation method in the heat exchange type primary reformer tubes and in traditional external-heat primary reformer tubes hydrocarbons steam reforming reaction such as methane be:

In secondary reformer, owing to added pure oxygen to secondary reformer, CO ₂Hydrocarbons such as gas and methane, so its steam reforming reaction is:

The synthetic gas that this preparation method obtained can be used for the unstripped gas of methyl alcohol and acetic acid process for combination producing process, also can produce methyl alcohol separately, and providing purity to other user simultaneously is 99.8% high-purity CO product gas, and the present invention has following characteristics:

1. this preparation method is better than traditional external-heat steam reforming technology, it can utilize the high level heat of secondary reformer exit gas to add the interior reactant of heat exchange type primary reformer tubes, for its steam reforming reaction provides essential heat, the fuel natural gas consumption and the smoke discharge amount of external-heat converter have been significantly reduced, certainly, also reduce the thermosteresis that causes with fume emission, for A series, realized half autothermal balance of hydrocarbon steam conversion reaction process substantially; For B series, except energy-saving effect that the heat exchange type one-stage converter brought and, the technology waste heat that can also utilize out two sections reforming gas between the heat exchange type primary reformer tubes simultaneously with Sweet natural gas/process steam charge heating to the heat exchange type temp at entrance of stage-one converter.As raw material hydrocarbon gas and technology oxygen and CO ₂The process furnace of preheating, its thermal load is extremely low, and its fuel gas both can be a spot of hydrocarbons, also can be methanol synthetic discharged gas delayed through H ₂And CO ₂Tail gas after the recovery, perhaps both gas mixtures, the production scene is difficult to the naked eye watch fume emission.Therefore B series has realized the autothermal balance of hydrocarbon steam conversion reaction process basically.

2. but owing to material quantity and other production control parameter independent regulation in A, B two each and every one converters of series, separation of C O ₂Amount also can control, therefore fundamentally solve hydrogen and the unbalanced problem of carbon.

3. thermo-efficiency height

This preparation method is with portion C H ₄Steam reforming is transferred to thermo-efficiency near two sections conversions of heat-insulating of 100% from one-stage converter.

4. can realize methyl alcohol and acetic acid combination producing, realize the resources circulation use.

5. risk is little, stable and reliable operation.A, B two series can be produced separately, also can adopt different production control parameters to produce separately.

Description of drawings

Fig. 1 prepares the system and the process flow sheet of CO and synthetic gas and methyl alcohol for the inventive method.

Embodiment

Referring to Fig. 1, unstripped gas through pipeline 1a (or with methanol synthetic discharged gas delayed isolating H from pipeline 3a ₂After the mixing) the unstripped gas preheat coil that enters in the convection zone of external-heat one-stage converter 9a is preheated to 250～430 ℃, enters hydrodesulphurisatioreactors reactors 6a through pipeline 5a then, to remove the deleterious sulphur of follow-up operation, catalyzer is housed in the reactor.The qualified gas of desulfurization is flowed out by pipeline 7a and with (pressure is 0.3～4.5MPa) to mix from the technological process steam of pipeline 23, be process feed gas, enter convection zone Sweet natural gas/steam preheating coil pipe of external-heat one-stage converter 9a, make temperature rise to 400～600 ℃, pressure is 0.2-4Mpa, enter respectively in the conversion tube of external-heat one-stage converter 9a and heat exchange type one-stage converter 10a through pipeline 8a, catalyzer all is housed in these conversion tubes.In heat exchange type one-stage converter 10a,, make raw material hydrocarbon and water vapor generation chemical reaction and generate CO and H by means of two sections heats that reforming gas provided of the high temperature that comes from secondary reformer 14a between conversion tube ₂, in external-heat one-stage converter 9a, the raw material hydrocarbon in the conversion tube still goes up the burning that is provided with by means of furnace roof (or furnace wall) and chews, and a certain amount of combustion heat by the next fuel gas of pipeline 25a that burn is kept itself and the required heat of steam reforming reaction.After two one-stage converter 9a and 10a conversion reaction separately proceed to a certain degree, flow out merging by outlet pipe 11a and enter secondary reformer 14a through pipeline 12a and 13a, catalyzer is housed in the secondary reformer, wherein the temperature of one section reforming gas of heat exchange type one-stage converter 10a outlet is 500～750 ℃, CH ₄Butt volume ratio in this section reforming gas is 12～16%; The temperature of one section reforming gas of external-heat one-stage converter 9a outlet is 700～800 ℃, CH ₄Butt volume ratio in this section reforming gas is 3～12%.Technology with oxygen through pipeline 2a with mix from the small amount of steam of pipeline 23 after, the convection zone that enters external-heat converter 9a is preheated to 250～350 ℃, enter secondary reformer 14a through pipeline 15a, with from one section reforming gas of pipeline 13a after fierce turbulence mixes, at first in the combustion reactions of furnace roof generation hydrogen and oxygen, for continue after the conversion reaction of the methane degree of depth essential heat is provided.The CO that retrieves from the stack gas of external-heat one-stage converter 9a ₂Through pipeline 4a with mix from the small amount of steam of pipeline 23 after enter external-heat converter 9a convection zone be preheated to 300～450 ℃ after, mix to enter secondary reformer again with the one section reforming gas that comes through pipeline 13a through pipeline 27a.The unstripped gas of handling through desulfurization without the part of one-stage converter carries out turbulence with one section reforming gas and technology with oxygen simultaneously and mixes, and carry out partial oxidation reaction in on-catalytic conversion reaction space through the burner that pipeline 22a enters secondary reformer.When two sections conversion reactions proceed to a certain degree, be that temperature out is when reaching 800～1050 ℃, secondary reformer is worked off one's feeling vent one's spleen and is entered between the pipe of heat exchange type one-stage converter 10a through pipeline 16a, high-order technology waste heat is passed to the interior reactant of pipe, self temperature is reduced to 500～750 ℃, enter the A end of reforming gas waste-heat boiler 24 through pipeline 17a and 18a, further reclaim heat in the reforming gas with the byproduct steam form, then through BFW preheater 20a and water cooler 21a, temperature is reduced to about 40 ℃ to send to through pipeline 28 and is made the methyl alcohol synthetic raw gas.

The raw material hydrocarbon gas through pipeline 1b (or with from isolating H in pipeline 3b methanol synthetic discharged gas delayed ₂Mix the back), enter process furnace 9b and be preheated to 330～410 ℃, hydrocarbon gas enters hydrogenating desulfurization groove 6b to remove the deleterious sulphur of follow-up operation through pipe 5b, and catalyzer is housed in the reactor.The qualified gas of desulfurization flows out and mixes with process steam from pipeline 23 that (vapor pressure is 0.3～4.5MPa) through pipeline 7b, be process feed gas, enter import/export interchanger 19 and be preheated to 400～600 ℃, pressure is 0.2～4Mpa, enter by pipeline 8b in the conversion tube of heat exchange type one-stage converter 10b, catalyzer is housed in the conversion tube, in the heat exchange type primary reformer tubes, by means of between pipe from two sections heats that reforming gas provided of high temperature of secondary reformer 14b, make raw material hydrocarbon and water vapor generation chemical reaction and generate CO and H ₂After the conversion reaction of heat exchange type one-stage converter 10b proceeds to a certain degree, flow out through outlet pipe 11b, enter heat-insulating secondary reformer 14b through pipeline 12b and 13b, be filled with catalyzer in the secondary reformer 14b, wherein the temperature at one section reforming gas in the exit of heat exchange type one-stage converter 10b is 500～750 ℃, CH ₄Butt volume ratio in this section reforming gas is 12～16%.Technology enters process furnace 9b with oxygen through pipe 2b, it is preheated to 250～350 ℃, enter the top of secondary reformer 14b through pipeline 15b, with from one section reforming gas of pipeline 13b at this after turbulence mixes, the combustion reactions of hydrogen and oxygen at first takes place at the top, for continue after the conversion reaction of the methane degree of depth needed heat is provided, the part of being come by pipeline 22b enters secondary reformer through the unstripped gas of desulfurization processing, carry out partial oxidation reaction in its uncatalyzed reaction space, the CO that retrieves from the stack gas of external-heat one-stage converter 9a ₂Gas by pipeline 4b enter process furnace 9b be preheated to 100～200 ℃ through pipeline 27b with enter secondary reformer 14b after one section reforming gas from pipeline 13b mixes and carry out CH ₄+ CO ₂Steam reforming reaction.Be preheated to 250～350 ℃ from the pure oxygen (mixing with small amount of steam) of pipeline 2b in process furnace 9b and enter secondary reformer through pipe 15b, at its top, oxygen carries out turbulence with one section reforming gas and Sweet natural gas to be mixed, the generation combustion reactions.Conversion reaction proceeds to a certain degree in secondary reformer, be that temperature out is when reaching 800～1050 ℃, secondary reformer 14b works off one's feeling vent one's spleen and enters between the pipe of heat exchange type one-stage converter 10b through pipeline 16b, high-order technology waste heat is passed to the interior reactant of pipe, self temperature is reduced to 500～750 ℃ and is entered the import/export interchanger through pipeline 17b unstripped gas is preheated to 400～600 ℃, self temperature reduces once again after pipeline 18b enters the B end of reforming gas waste-heat boiler 24, further reclaim heat in the reforming gas with the form of byproduct steam, then through feedwater preheater 20b and watercooler 21b, water is cooled to reforming gas and enters PSA transformation adsorption separation device 29 about 40 ℃, part CO in the reforming gas is separated, send to the unstripped gas of making methanol carbonyl synthesized acetic acid, the tail gas behind the separation of C O is because of containing a large amount of H ₂, CO ₂And active principle such as CO, mix with reforming gas through pipeline 32 by pipeline 28, send to and make methyl methanol syngas.Control the output of methyl alcohol with the size of regulating PSA by-pass valve.The steam of reforming gas waste-heat boiler 24 by-products divides through drum and to send to house steward by pipeline 23 after dried up.

The CO that in above-mentioned technological process, in secondary reformer 14a, adds ₂Be respectively 0～25% and 0～28% of the unstripped gas total carbon mole number that enters through pipeline 1a with the mole number of the unstripped gas of hydrocarbon-containifirst material; The CO that in secondary reformer 14b, adds ₂Be respectively 0～45% and 0～35% of the unstripped gas total carbon mole number that enters through pipeline 1b with the mole number of the unstripped gas of hydrocarbon-containifirst material; The pure oxygen amount that adds in the 14b in secondary reformer is wanted to keep system's thermal equilibrium, and is guaranteed CH in two sections reforming gas ₄The butt volume ratio be 2～0.3%.

Mix the synthetic gas that obtains with reforming gas in the process of synthesizing methanol from the tail gas behind the PSA tripping device cutting out partial CO, from the off-gas that produces, separate the H that obtains by pipeline 28 ₂, rich CO ₂Gas and tail gas are got back to pipeline 3a and 3b (H again respectively ₂), pipeline 4a and 4b (CO ₂) and 25a and 25b (tail gas act as a fuel gas) position, realize that resources circulation uses.

But since material quantity and other production control parameter independent regulation in each converter in this technological process, separation of C O ₂Amount also can control, therefore can guarantee that the synthetic gas that obtains can be used in the low pressure methanol synthesis technique.

It should be noted last that: above embodiment is the unrestricted technical scheme of the present invention in order to explanation only, although the present invention is had been described in detail with reference to the foregoing description, those of ordinary skill in the art is to be understood that, still can to the present invention make amendment and or be equal to replacement, and do not break away from the spirit and scope of the present invention.

Claims (10)

1, a kind of hydrocarbon vapours built-up type transforms the method for preparing CO and synthetic gas, it is characterized in that:

1), adopt A, two series of B, in the A series, an external-heat one-stage converter that enters respectively after the unstripped gas of hydrocarbon-containifirst material and the vapor mixing and a heat exchange type one-stage converter, described external-heat one-stage converter and heat exchange type one-stage converter are finished one section steam reforming reaction of hydrocarbons jointly, steam reforming reaction institute heat requirement is from the high level heat of two sections reforming gas of high temperature of secondary reformer generation in the described heat exchange type one-stage converter, this heat obtains by the indirect heat exchange between two sections reforming gas of described high temperature and the described heat exchange type one-stage converter inner reaction tube thing, described external-heat one-stage converter is chewed combustion fuel gas by burning, for the hydrocarbon steam conversion reaction provides heat, enter described secondary reformer after one section reforming gas that reaction generates in described heat exchange type one-stage converter and the external-heat one-stage converter mixes and carry out CH ₄Degree of depth conversion reaction; In the B series, the unstripped gas of hydrocarbon-containifirst material and vapor mixing are after after the import/export interchanger preheating, enter a heat exchange type one-stage converter and carry out one section steam reforming reaction, steam reforming reaction institute heat requirement is from the high level heat of two sections reforming gas of high temperature of secondary reformer generation in the described heat exchange type one-stage converter, this heat obtains by the indirect heat exchange between two sections reforming gas of described high temperature and the described heat exchange type one-stage converter inner reaction tube thing, and one section reforming gas that reaction generates in the described heat exchange type one-stage converter enters described secondary reformer and carries out CH ₄Degree of depth conversion reaction; Secondary reformer in described A, B two series adds CO respectively ₂Gas is in order to regulate the H of the two sections reforming gas of high temperature that generate ₂/ C ratio, or add pure oxygen in the secondary reformer in described A, B two series, in order to keep minimum N in two sections reforming gas of system's thermal equilibrium and high temperature ₂Content, or add the unstripped gas contain hydrocarbons in the secondary reformer in described A, B two series is in order to the content that increases CO in two sections reforming gas of high temperature and can be energy-conservation;

2), after two sections reforming gas of high temperature of generating of the secondary reformer described in the B series offer described heat exchange type one-stage converter with heat, after reducing temperature, heat recovery equipment enters the CO tripping device again, cutting out partial CO; After two sections reforming gas of high temperature that secondary reformer described in the A series generates offer described heat exchange type one-stage converter with heat, through heat recovery equipment, mixes with the tail gas behind two sections reforming gas separate part CO of the described secondary reformer of B series, be used as synthetic gas.

2, hydrocarbon vapours built-up type according to claim 1 transforms the method for preparing CO and synthetic gas, it is characterized in that the unstripped gas described in two series of A, B is separate, the mol ratio of total carbon is 1.8～4.5 for A series in steam and the unstripped gas, for B series is 1.0～4, the pressure that enters the gas mixture of interior unstripped gas of heat exchange type primary reformer tubes described in heat exchange type one-stage converter described in the A series and described external-heat one-stage converter and the B series and steam is 0.2～4MPa, and temperature is 400～600 ℃; The temperature of one section reforming gas in the exit of heat exchange type one-stage converter is 500～750 ℃ described in heat exchange type one-stage converter described in the A series and the B series, CH ₄Butt volume ratio therein is 12～26%; The temperature of one of the exit of external-heat primary reformer tubes section reforming gas is 700～800 ℃ described in the A series, CH ₄Butt volume ratio therein is 3～12%; The temperature of two sections reforming gas in the exit of secondary reformer is 800～1050 ℃ described in secondary reformer described in the A series and the B series.

3, hydrocarbon vapours built-up type according to claim 1 and 2 transforms the method for preparing CO and synthetic gas, it is characterized in that the CO that adds in described secondary reformer in the A series ₂Mole number be 0～25% of A series raw material gas total carbon mole number, the CO that in described secondary reformer, adds in the B series ₂Mole number be unstripped gas total carbon mole number 0～45%; The mole number of the unstripped gas of the hydrocarbon-containifirst material that adds in described secondary reformer in the A series is 0～28% of an A series raw material gas total carbon mole number, and the mole number of the unstripped gas of the hydrocarbon-containifirst material that adds in described secondary reformer in the B series is 0～35% of a unstripped gas total carbon mole number; The pure oxygen amount that adds in described secondary reformer in the B series is wanted to keep system's thermal equilibrium, and is guaranteed CH in its two sections reforming gas ₄The butt volume ratio be 2～0.3%.

4, hydrocarbon vapours built-up type according to claim 1 and 2 transforms the method for preparing CO and synthetic gas, it is characterized in that the CO described in the step 1) ₂Be from the combustion product gases of external-heat one-stage converter described in the A series, to reclaim.

5, hydrocarbon vapours built-up type according to claim 4 transforms the method for preparing CO and synthetic gas, it is characterized in that described combustion product gases is reclaiming CO ₂Before, the CO that is provided with the convection zone of described external-heat one-stage converter ₂Preheat coil, hydro carbons gas/steam preheating coil pipe, hydro carbons gas preheat coil, oxygen preheat coil pipe and the heat exchange of combustion air preheat coil enter stack gas after self temperature reduces and reclaim CO ₂Device.

6, hydrocarbon vapours built-up type according to claim 1 and 2 transforms the method for preparing CO and synthetic gas, it is characterized in that the H in the described synthetic gas ₂, CO and CO ₂Gas composition meets the following conditions, and is used for the low pressure methanol synthesis technique:

$f=\frac{H_2-{\mathrm{CO}}_2}{\mathrm{CO}+{\mathrm{CO}}_2}=2.05~2.15$

In the formula: f-ratio, no unit,

H ₂The molar flow of-hydrogen, kmol/h,

CO ₂The molar flow of-carbonic acid gas, kmol/h,

The molar flow of CO-carbon monoxide, kmol/h.

7, the CO of the described method preparation of a kind of claim 1 is as the methanol carbonyl synthesized acetic acid unstripped gas.

8, the synthetic gas of the described method preparation of a kind of claim 1 is as the methyl alcohol synthetic raw gas.

9, a kind of method of utilizing synthesis gas preparation methyl alcohol, the H that the off-gas that it is characterized in that producing in the synthesis gas preparation methanol process obtains through separation ₂, rich CO ₂Gas and tail gas turn back in the synthesis gas preparation process, realize resource circulation utilization.

10, the method for utilizing synthesis gas preparation methyl alcohol according to claim 9 is characterized in that the preparation method of described synthetic gas is as follows:

1), adopt two series of A, B, in the A series, the off-gas that produces in the unstripped gas of hydrocarbon-containifirst material and the methyl alcohol building-up process is through separating the H that obtains ₂After the mixing again with vapor mixing after the external-heat one-stage converter and the heat exchange type one-stage converter that enter respectively, described external-heat one-stage converter and heat exchange type one-stage converter are finished one section steam reforming reaction of hydrocarbons jointly, steam reforming reaction institute heat requirement is from the high level heat of two sections reforming gas of high temperature of secondary reformer generation in the described heat exchange type one-stage converter, this heat obtains by the indirect heat exchange between two sections reforming gas of described high temperature and the described heat exchange type one-stage converter inner reaction tube thing, described external-heat one-stage converter is chewed combustion fuel gas by burning and is provided heat for hydrocarbon steam conversion reaction, the part of described fuel gas from the off-gas that produces in the methyl alcohol building-up process through separating H ₂And CO ₂After tail gas; Enter described secondary reformer after one section reforming gas that reaction generates in described heat exchange type one-stage converter and the external-heat one-stage converter mixes and carry out CH ₄Degree of depth conversion reaction; In the B series, the unstripped gas of hydrocarbon-containifirst material and vapor mixing are after after the import/export interchanger preheating, enter a heat exchange type one-stage converter and carry out one section steam reforming reaction, steam reforming reaction institute heat requirement is from the high level heat of two sections reforming gas of high temperature of secondary reformer generation in the described heat exchange type one-stage converter, this heat obtains by the indirect heat exchange between two sections reforming gas of described high temperature and the described heat exchange type one-stage converter inner reaction tube thing, and one section reforming gas that reaction generates in the described heat exchange type one-stage converter enters described secondary reformer and carries out CH ₄Degree of depth conversion reaction; Secondary reformer in described A, B two series adds the CO that the off-gas that produces in the methyl alcohol building-up process obtains through separation respectively ₂Gas is in order to regulate the H of the two sections reforming gas of high temperature that generate ₂/ C ratio, or add pure oxygen in the secondary reformer in described A, B two series, in order to keep minimum N in two sections reforming gas of system's thermal equilibrium and high temperature ₂Content, or add the unstripped gas contain hydrocarbons in the secondary reformer in described A, B two series is in order to the content that increases CO in two sections reforming gas of high temperature and can be energy-conservation;

2), after two sections reforming gas of high temperature of generating of the secondary reformer described in the B series offer described heat exchange type one-stage converter with heat, after reducing temperature, heat recovery equipment enters the CO tripping device again, cutting out partial CO; After two sections reforming gas of high temperature that secondary reformer described in the A series generates offer described heat exchange type one-stage converter with heat, through heat recovery equipment, mixes with the tail gas behind two sections reforming gas separate part CO of the described secondary reformer of B series, be used as synthetic gas.