阅读说明：本技术 一种烃类二氧化碳重整制取一氧化碳的方法 (Method for preparing carbon monoxide by reforming hydrocarbon carbon dioxide ) 是由 蹇守华 马磊 周君 汪涛 张新波 刘玉成 肖云山 黄晓春 杨建军 倪文龙 刘光伦 于 2021-10-15 设计创作，主要内容包括：本发明为一种烃类二氧化碳重整制取一氧化碳的方法,该方法中,补加的二氧化碳和烃类气体经过压缩、加热后进入脱硫系统脱出硫化物,然后与系统返回的二氧化碳、氢气混合,进入喷射器引射重整气循环,并与重整气混合后进入重整反应器,通入氧气进行二氧化碳与烃类重整反应,得到含一氧化碳和氢气的高温重整气,高温重整气经过多级热量回收并经冷却器冷却到常温后进入脱碳系统Ⅰ,脱碳系统Ⅰ脱出的二氧化碳与后续脱碳系统Ⅱ脱出的二氧化碳经过加压循环等。本发明采用烃类二氧化碳重整工艺,重整不配蒸汽,节省蒸汽消耗,同时得到高浓度一氧化碳重整气,系统产生的二氧化碳不仅全回收,还外补二氧化碳,实现碳减排。(The invention relates to a method for preparing carbon monoxide by reforming hydrocarbon carbon dioxide, in the method, supplemented carbon dioxide and hydrocarbon gas enter a desulfurization system to remove sulfide after being compressed and heated, then are mixed with carbon dioxide and hydrogen returned by the system, enter an ejector to inject reformed gas circulation, enter a reforming reactor after being mixed with the reformed gas, introduce oxygen to carry out carbon dioxide and hydrocarbon reforming reaction to obtain high-temperature reformed gas containing carbon monoxide and hydrogen, the high-temperature reformed gas enters a decarburization system I after being cooled to normal temperature by a cooler after being subjected to multi-stage heat recovery, and the carbon dioxide removed by the decarburization system I and the carbon dioxide removed by a subsequent decarburization system II are subjected to pressurization circulation and the like. The invention adopts hydrocarbon carbon dioxide reforming technology, steam is not matched for reforming, steam consumption is saved, high-concentration carbon monoxide reformed gas is obtained, carbon dioxide generated by the system is fully recycled, and carbon dioxide is supplemented externally, thus realizing carbon emission reduction.)

1. A method for preparing carbon monoxide by reforming hydrocarbon carbon dioxide is characterized by comprising the following steps:

1) mixing the raw material gas of hydrocarbon with carbon dioxide gas, compressing, preheating the compressed mixed gas in a preheater by using high-temperature reformed gas at the outlet of reforming reaction, purifying the preheated mixed gas in a desulfurizing device, and purifying the purified mixed gas and the subsequent CO₂Compressor, H₂After the gas preheated by the high-temperature reformed gas is pressurized and mixed by the compressor, part of the high-temperature reformed gas at the outlet of the reforming device is guided to the inlet of the reforming device by utilizing the power energy of the gas, the part of the high-temperature reformed gas comes from the outlet of the reforming reactor or the outlet of the steam generator, and meanwhile, oxygen is introduced into the reforming device to carry out hydrocarbon carbon dioxide reforming reaction with the inlet gas of the reforming device;

(2) guiding a high-temperature reformed gas part at the outlet of the reforming reactor by using an ejector to return to the step (1) to be used as circulating gas, preheating raw gas by using a preheater I, preheating carbon dioxide and hydrogen mixed gas by using a preheater II, recovering low-level heat by using a decarbonization device I and a decarbonization device II, cooling, separating steam from water to obtain low-temperature reformed gas, wherein the heat utilization sequence of the high-temperature reformed gas from the steam generator is not unique;

(3) the high-temperature reformed gas at the outlet of the reforming reactor can pass through a steam generator to produce steam by-product, then the high-temperature reformed gas is drained by an ejector and returns to the step (1), and the rest high-temperature reformed gas is the same as the step (2);

(4) the low-temperature reformed gas obtained in the step (2) or (3) firstly enters a decarbonization device I, and carbon dioxide recovered from the low-temperature reformed gas is mixed with carbon dioxide recovered from a post-process decarbonization device II and then enters CO₂The decarbonizing device preferably performs MDEA decarbonization, a reboiler heat source in the decarbonizing device is from low-level heat of reformed gas, and the decarbonized reformed gas enters a PSA carbon monoxide purification device to obtain a high-purity carbon monoxide product;

(5) the reformed gas after purifying the carbon monoxide enters a conversion device to carry out conversion reaction on the carbon monoxide which is not separated by the PSA carbon monoxide extraction device in the step (4), the converted gas enters a decarbonization device II to recover the carbon dioxide and a decarbonization device IMixing the recovered carbon dioxide; the synthesis gas without carbon dioxide enters a PSA hydrogen extraction device to extract hydrogen in the residual synthesis gas, and the hydrogen enters H₂A compressor;

(6)CO₂carbon dioxide and H pressurized by compressor₂And hydrogen pressurized by the compressor enters a preheater II, the mixed gas is subjected to heat exchange by using the high-temperature reformed gas and then is mixed with the desulfurized feed gas, and before the mixed gas returns to the ejector, part of the high-temperature circulating reformed gas can be circulated back to the inlet of the reforming device by using the kinetic energy of the mixed gas.

2. The process for producing carbon monoxide by reforming of carbon dioxide hydrocarbons according to claim 1, wherein: the hydrocarbon raw material gas in the step (1) is gaseous hydrocarbon at normal temperature or liquid hydrocarbon which is gaseous after being heated.

3. The process for producing carbon monoxide by reforming of carbon dioxide hydrocarbons according to claim 1, wherein: the volume ratio of the mixture of the hydrocarbon raw material gas and the externally-supplemented carbon dioxide is 5: 1.

4. The process for producing carbon monoxide by reforming of carbon dioxide hydrocarbons according to claim 1, wherein: in the step (1), the pressure of the gas entering the preheater I is 0.8MPa (G) to 4.5MPa (G).

5. The process for producing carbon monoxide by reforming of carbon dioxide hydrocarbons according to claim 1, wherein: in the step (1), the temperature of the purified gas entering the desulfurization device is 320-350 ℃.

6. The process for producing carbon monoxide by reforming of carbon dioxide hydrocarbons according to claim 1, wherein: in the step (3), the flow rate of the circulating gas is controlled by adjusting the flow rate of the raw material gas mixture of the ejector, so that the temperature of the mixed raw material gas and the circulating gas is controlled to be above the spontaneous combustion point of the mixed gas, the water-carbon ratio of the reforming reaction inlet is met, and the carbon is prevented from being precipitated in the reforming reaction.

7. The process for producing carbon monoxide by reforming of carbon dioxide hydrocarbons according to claim 1, wherein: the circulating gas injected and injected to return is reformed gas from the outlet of the reforming reactor or reformed gas from the outlet of the steam generator.

8. The process for producing carbon monoxide by reforming of carbon dioxide hydrocarbons according to claim 1, wherein: in the step (4), high-temperature reformed gas at the outlet of the reforming reactor firstly enters a steam generator to generate steam, then exchanges heat with a feed gas hydrocarbon raw gas and external carbon dioxide supplement mixed gas preheater I, a circulating carbon dioxide and hydrogen mixed gas preheater II, a boiler feed water preheater, a regeneration reboiler of the decarbonization device I and a regeneration reboiler of the decarbonization device II respectively, and finally is cooled to normal temperature through a cooler.

9. The process for producing carbon monoxide by reforming of carbon dioxide hydrocarbons according to claim 1, wherein: and adjusting the volume percentage of the hydrogen purified by the PSA to return to the reforming device within 0-100% according to the requirement.

10. The process for producing carbon monoxide by reforming of carbon dioxide hydrocarbons according to claim 1, wherein: the hydrocarbon raw material gas is gaseous mixed hydrocarbon gas after naphtha is heated or ocean exploitation natural gas.

Technical Field

The invention relates to the field of synthesis gas preparation, in particular to a method for preparing carbon monoxide by reforming hydrocarbon carbon dioxide.

Background

Carbon monoxide is used as an important raw material gas of an industrial device, and plays an important role in the metallurgical industry, the chemical industry, the petrochemical industry and important fields. The existing method for preparing carbon monoxide from hydrocarbons comprises two processes of hydrocarbon steam conversion and hydrocarbon steam-series pure oxygen conversion.

Hydrocarbon steam conversion process: the hydrocarbon and steam are converted in the reaction tube with conversion catalyst, and the conversion rate of hydrocarbon can be ensured only by external heating because the hydrocarbon steam conversion reaction is endothermic, because of the influence of heat transfer and material, the steam reforming reaction of the hydrocarbon is generally not over 850 ℃, and in order to prevent the high-temperature carbon deposition of the hydrocarbon and influence the service life of the catalyst, a certain water-carbon ratio (the ratio of water to the carbon contained in the hydrocarbon) must be ensured, so that a large amount of water vapor is required to be added, because the steam adding amount is large and is influenced by the balance of the conversion reaction, the content of carbon dioxide and methane in the synthesis gas obtained by the hydrocarbon steam conversion process is high, the content of carbon monoxide is low, meanwhile, the conversion adopts indirect heating to provide heat, needs to burn part of hydrocarbons, increases the consumption of raw materials, moreover, the reformer investment is high, and the investment and cost per unit quantity of carbon monoxide obtained from the hydrocarbon steam reforming process is high. The combustion of fuels produces large greenhouse gas carbon dioxide emissions that can have adverse environmental effects.

Hydrocarbon steam-series pure oxygen conversion process: firstly, a part of hydrocarbon and steam are converted in a reaction tube filled with a conversion catalyst, then the hydrocarbon and the rest of hydrocarbon are mixed and enter a pure oxygen converter filled with the conversion catalyst to be converted with the steam under the heat provided by oxygen combustion. Because the outlet temperature of the pure oxygen conversion reactor is higher than the outlet temperature of the hydrocarbon steam conversion reactor, and the water-carbon ratio of the inlet of the pure oxygen conversion furnace is lower than the water-carbon ratio of the inlet of the hydrocarbon steam conversion reactor, the content of carbon dioxide and methane in the synthetic gas obtained by the hydrocarbon steam-series pure oxygen conversion process is lower than that of the pure hydrocarbon steam conversion process, the content of carbon monoxide is high, and because the water vapor is added, the carbon dioxide is also high, and like the hydrocarbon steam conversion process, the emission of a large amount of greenhouse gas carbon dioxide generated by fuel combustion can cause adverse effects on the environment.

Disclosure of Invention

The purpose of the invention is: aiming at the problems, the method and the device for preparing the carbon monoxide by reforming the hydrocarbon carbon dioxide are provided, the problem that a reforming device needs steam is solved by adopting a mode of partial reforming outlet gas circulation, the characteristic of no power of the reforming device is achieved by utilizing a mode that high-pressure raw material gas adopts an ejector, the problem that circulating gas needs cooling when compressed is omitted, and the energy consumption is further reduced. The carbon dioxide is proportioned by hydrocarbons and the carbon dioxide removed in the subsequent process is returned to improve the content of the carbon monoxide in the reformed gas, and simultaneously, the consumption of raw material gas, the consumption of steam and the operation cost are greatly reduced. Carbon dioxide gas is not discharged in the device, and carbon neutralization of the device is realized.

In order to achieve the above purpose, the specific technical scheme of the invention is as follows:

a method for preparing carbon monoxide by reforming hydrocarbon carbon dioxide comprises the following steps:

(1) mixing the raw material gas of hydrocarbon with carbon dioxide gas, compressing, preheating the compressed mixed gas in a preheater by using high-temperature reformed gas at the outlet of reforming reaction, purifying the preheated mixed gas in a desulfurizing device, and purifying the purified mixed gas and the subsequent CO₂Compressor, H₂After the gas preheated by the high-temperature reformed gas is pressurized and mixed by the compressor, part of the high-temperature reformed gas at the outlet of the reforming device is guided to the inlet of the reforming device by utilizing the power energy of the gas, the part of the high-temperature reformed gas can come from the outlet of the reforming reactor or the outlet of the steam generator, and meanwhile, oxygen is introduced into the reforming device to carry out hydrocarbon carbon dioxide reforming reaction with the inlet gas of the reforming device;

(2) guiding a high-temperature reformed gas part at the outlet of the reforming reactor by using an ejector to return to the step (1) to be used as circulating gas, preheating raw gas by using a preheater I, preheating carbon dioxide and hydrogen mixed gas by using a preheater II, recovering low-level heat by using a decarbonization device I and a decarbonization device II, cooling, separating steam from water to obtain low-temperature reformed gas, wherein the heat utilization sequence of the high-temperature reformed gas from the steam generator is not unique;

(3) the high-temperature reformed gas at the outlet of the reforming reactor can pass through a steam generator to produce steam by-product, then the high-temperature reformed gas is drained by an ejector and returns to the step (1), and the rest high-temperature reformed gas is the same as the step (2);

(4) the low-temperature reformed gas obtained in the step (2) or (3) firstly enters a decarbonization device I, and carbon dioxide recovered from the low-temperature reformed gas is mixed with carbon dioxide recovered from a post-process decarbonization device II and then enters CO₂The compressor and the decarbonization device preferably adopt MDEA for decarbonization, a reboiler heat source in the decarbonization device is from low-level heat of the reformed gas, and the decarbonized reformed gas enters the PSA carbon monoxide purification device to obtain a high-purity carbon monoxide product.

(5) Purification ofAnd (4) the reformed gas after the carbon monoxide enters a conversion device, the carbon monoxide which is not separated by the PSA carbon monoxide extraction device in the step (4) is subjected to conversion reaction, the converted gas enters a decarburization device II, and the recovered carbon dioxide is mixed with the carbon dioxide recovered by the decarburization device I. The synthesis gas without carbon dioxide enters a PSA hydrogen extraction device to extract hydrogen in the residual synthesis gas, and the hydrogen enters H₂A compressor;

(6)CO₂carbon dioxide and H pressurized by compressor₂And hydrogen pressurized by the compressor enters a preheater II, the mixed gas is subjected to heat exchange by using the high-temperature reformed gas and then is mixed with the desulfurized feed gas, and before the mixed gas returns to the ejector, part of the high-temperature circulating reformed gas can be circulated back to the inlet of the reforming device by using the kinetic energy of the mixed gas.

In a preferred embodiment of the present invention, in the step (1), the raw material gas is a hydrocarbon gas, and the hydrocarbon gas is a hydrocarbon gas which is gaseous at normal temperature, a liquid hydrocarbon which is gaseous after heating, or a mixed hydrocarbon gas which is gaseous after heating, such as naphtha.

In a preferred embodiment of the present invention, in step (1), the gas pressure fed into the preheater I is 0.8MPa (G) to 4.5MPa (G).

In a preferred embodiment of the present invention, in the step (1), the temperature of the purge gas introduced into the desulfurization apparatus is 320 to 350 ℃.

As a preferred embodiment of the present application, the high temperature reformed gas is divided into two parts, and the high temperature reformed gas may be separated before entering the steam generator or after entering the steam generator. And (3) draining part of high-temperature reformed gas by an ejector, returning the part of the high-temperature reformed gas to the step (1) as circulating gas for adjusting the temperature, the pressure and the water-carbon ratio of the reforming device, and preheating the mixture of the raw material hydrocarbon and the carbon dioxide and the mixture of the circulating carbon dioxide and the hydrogen after the other part of the reformed outlet gas recovers high-level heat, wherein the preheating sequence is not unique. The low-level heat of the reformed gas is used for supplying heat to reboilers of the first decarbonizing device tower and the second decarbonizing device tower, and the reformed gas is cooled and separated from the gas when the low-level heat of the reformed gas is unavailable.

In a preferred embodiment of the present invention, the flow rate of the recycle gas introduced by the ejector is controlled by the temperature, water-carbon ratio, pressure, and the like at the inlet and outlet of the reformer.

As a preferred embodiment of the present invention, a two-stage decarbonization apparatus is used, and the carbon dioxide by-produced in the reforming apparatus is recovered and passed through CO₂The compressed gas is mixed with PSA hydrogen extraction device via H₂The hydrogen pressurized by the compressor is mixed, the mixture is preheated by the heat of the high-temperature reformed gas and then is mixed with the feed gas, and the carbon elimination effect of the carbon dioxide and the hydrogen in the reforming reaction is utilized, so that the reforming device does not need additional steam.

As a preferred embodiment herein, the present invention further comprises a system for carrying out the above process for producing synthesis gas by reforming hydrocarbons, said system comprising a preheater, a desulfurization unit, a heat exchanger, a reforming reactor, a steam generator, an ejector, a heat recovery unit, a decarbonization unit, a PSA purification unit, and a shift unit; the hydrocarbon preheater is connected with the desulfurization tank, the desulfurization tank is connected with a tube pass inlet of the heat exchanger, a tube pass outlet of the heat exchanger is connected with an inlet of the conversion reactor, an outlet part of the conversion reactor is connected with the ejector, the other part of the conversion reactor is connected with a heat source inlet of the steam generator, a heat source outlet of the steam generator is connected with a shell pass inlet of the heat exchanger and enters the hydrocarbon preheater to exchange heat with feed gas, and then the hydrocarbon preheater and the feed gas are sequentially connected with the heat recovery device. The synthesis gas passing through the heat recovery device enters a decarbonization device I to be decarbonized for the first time, then a carbon monoxide product is obtained through a PSA carbon monoxide extraction device, the rest part is converted into hydrogen and carbon dioxide through a conversion device, secondary decarbonization is carried out through a decarbonization device II, and the decarbonized gas is extracted into hydrogen through the PSA hydrogen extraction device.

As a preferred embodiment of the present invention, the conversion reactor may be a non-catalytic reactor or a catalytic reactor.

Compared with the prior art, the invention has the beneficial effects that:

the reforming is not matched with steam, the power of the mixed gas is directly utilized to drain and return the high-temperature reformed gas rich in water at the outlet of the reforming reactor, so that the compression power consumption and the compression investment of the returned gas are saved, and the zero steam consumption of the reforming device is realized; the steam consumption is saved.

And (II) high-temperature circulating gas is mixed with the raw material gas to reach the temperature required by the reforming reaction, and the system does not need an external heating source, so that a large amount of energy consumption is saved.

And (III) returning carbon dioxide generated in the system to the reforming device for reaction, and adding carbon dioxide through raw material hydrocarbons to realize negative carbon emission of the system.

And (IV) the hydrocarbon consumption is greatly reduced by adjusting the proportion of carbon dioxide in the fed hydrocarbons and circulating hydrogen, and is reduced by 20 percent compared with the hydrocarbon consumption in the prior art.

And (V) a hydrocarbon steam conversion reactor is cancelled, so that a large amount of investment is saved, the heating fuel quantity required by the steam conversion reaction is saved, and the negative carbon emission target in the effect 3 is realized. The carbon dioxide gas generated by the reforming reaction is recovered by the subsequent decarbonization device and returns to the reforming device, and the device has no carbon dioxide emission. Meanwhile, the carbon dioxide is added into the feed gas, so that the hydrocarbon consumption is reduced, and the yield of the carbon monoxide product is improved.

Drawings

FIG. 1 is a schematic flow chart of a process for producing carbon monoxide by reforming a hydrocarbon with carbon dioxide according to example 1 of the present invention;

FIG. 2 is a schematic flow chart of a carbon monoxide preparation technology by reforming a carbon dioxide-rich natural gas according to example 2 of the present invention;

FIG. 3 is a schematic flow chart of a carbon monoxide preparation technology by carbon dioxide-supplemented reforming of a carbon dioxide-rich natural gas according to example 3 of the present invention.

Detailed Description

A method for preparing carbon monoxide by reforming hydrocarbon carbon dioxide comprises the following steps:

(1) mixing hydrocarbon raw material gas with externally-supplemented carbon dioxide, compressing the mixture to a certain pressure, then feeding the mixture into a preheater I, preheating the mixture by utilizing reformed high-temperature gas, and then feeding the preheated mixture into a desulfurization device for purification;

(2) and (3) compressing the carbon dioxide desorbed from the decarbonizing device I and the decarbonizing device II to the pressure consistent with the mixed raw material gas through a carbon dioxide compressor, mixing the compressed carbon dioxide with the hydrogen compressed by the hydrogen compressor of the PSA hydrogen extraction device, and then entering a preheater II to preheat by utilizing reformed high-temperature gas.

(3) Uniformly mixing the desulfurized raw material mixed gas with the preheated carbon dioxide and hydrogen mixed gas, then feeding the mixture into an ejector, and draining part of reformed gas to return to an inlet of a reforming device to be used as circulating gas;

in the step, the flow rate of the circulating gas is controlled by adjusting the flow rate of the raw material gas mixture of the ejector, so that the temperature of the mixed raw material gas and the circulating gas is controlled to be above the spontaneous combustion point of the mixed gas, the water-carbon ratio of the reforming reaction inlet is met, and the carbon is prevented from being precipitated in the reforming reaction.

(4) The gas at the outlet of the ejector enters a reforming device for reforming reaction, oxygen is added into the reforming device at the same time, part of the high-temperature reformed gas at the outlet of the reforming reactor returns to the ejector in the step (3) to be used as circulating gas, the other part of the high-temperature reformed gas is utilized step by step through heat, and finally the normal-temperature reformed gas is obtained after steam-water separation;

in the step, high-temperature reformed gas at the outlet of a reforming reactor firstly enters a steam generator to generate steam, then exchanges heat with a feed gas hydrocarbon raw gas and an external carbon dioxide supplement mixed gas preheater I, a circulating carbon dioxide and hydrogen mixed gas preheater II, a boiler feed water preheater, a regeneration reboiler of a decarbonization device I and a regeneration reboiler of the decarbonization device II respectively, and is cooled to normal temperature through a cooler.

(5) And (4) allowing the normal-temperature reformed gas in the step (4) to enter a decarbonization device I, separating carbon dioxide from the reformed gas, and sending the separated carbon dioxide to the carbon dioxide compressor in the step (2). The decarbonized reformed gas enters a PSA carbon monoxide purification device, and a carbon monoxide product is obtained through PSA separation;

(6) and (3) the reformed gas from which the carbon monoxide is removed in the step (5) enters a conversion device, most of the remaining carbon monoxide is converted into hydrogen and carbon dioxide, then the hydrogen and the carbon dioxide are removed through a decarbonization device II, the carbon dioxide is sent to the carbon dioxide compressor in the step (2), the remaining gas enters a PSA hydrogen extraction device, and the extracted hydrogen enters the hydrogen compressor in the step (2).

The amount of the hydrogen gas purified by the PSA can be adjusted within 0-100% according to the requirement.

Preferably, in the step (1), the raw material gas is a hydrocarbon gas, and the hydrocarbon gas is a hydrocarbon gas which is gaseous at normal temperature, a liquid hydrocarbon which is gaseous after heating, or a mixed hydrocarbon gas which is gaseous after heating, such as naphtha.

Preferably, in step (1), the gas pressure entering the preheater I is 0.8MPa (G) to 4.5MPa (G).

Preferably, in the step (1), the temperature of the purge gas introduced into the desulfurization apparatus is 320 to 350 ℃.

Preferably, the high temperature reformed gas is divided into two parts, and the high temperature reformed gas may be separated before entering the steam generator or after the steam generator. And (3) draining part of high-temperature reformed gas by an ejector, returning the part of the high-temperature reformed gas to the step (1) as circulating gas for adjusting the temperature, the pressure and the water-carbon ratio of the reforming device, and preheating the mixture of the raw material hydrocarbon and the carbon dioxide and the mixture of the circulating carbon dioxide and the hydrogen after the other part of the reformed outlet gas recovers high-level heat, wherein the preheating sequence is not unique. The low-level heat of the reformed gas is used for supplying heat to reboilers of the first decarbonizing device tower and the second decarbonizing device tower, and the reformed gas is cooled and separated from the gas when the low-level heat of the reformed gas is unavailable.

Preferably, in the present application, the circulating gas flow rate guided by the ejector is controlled by the temperature, water-carbon ratio, pressure and the like of the inlet and the outlet of the reforming device, and the circulating gas returned by the ejector can be from the reformed gas at the outlet of the reforming reactor or from the reformed gas at the outlet of the steam generator.

Preferably, the method utilizes a two-stage decarbonization device, the byproduct carbon dioxide of the reforming device is recovered and is pressurized by a CO2 compressor, then is mixed with hydrogen pressurized by an H2 compressor of a PSA hydrogen extraction device, is preheated by the heat of high-temperature reformed gas and is then mixed with raw material gas, and the carbon elimination effect of the carbon dioxide and the hydrogen in the reforming reaction is utilized, so that the reforming device does not need additional steam.

Preferably, the invention also comprises a system for implementing the method for preparing the synthesis gas by converting the hydrocarbons, wherein the system comprises a preheater, a desulfurization device, a heat exchanger, a conversion reactor, a steam generator, an ejector, a heat recovery device, a decarburization device, a PSA purification device and a conversion device; the device comprises a hydrocarbon preheater, a desulfurization tank device, a heat exchanger, a conversion reactor, a steam generator and a heat source, wherein the hydrocarbon preheater is connected with the desulfurization tank device, the desulfurization device is connected with a tube pass inlet of the heat exchanger, a tube pass outlet of the heat exchanger is connected with an inlet of the conversion reactor, an outlet part of the conversion reactor is connected with an ejector, the other part of the conversion reactor is connected with a heat source inlet of the steam generator, a heat source outlet of the steam generator is connected with a shell pass inlet of the heat exchanger, enters the hydrocarbon preheater for exchanging heat with feed gas, and is sequentially connected with a heat recovery device. The synthesis gas passing through the heat recovery device enters a decarbonization device I to be decarbonized for the first time, then a carbon monoxide product is obtained through a PSA carbon monoxide extraction device, the rest part is converted into hydrogen and carbon dioxide through a conversion device, secondary decarbonization is carried out through a decarbonization device II, and the decarbonized gas is extracted into hydrogen through the PSA hydrogen extraction device.

Preferably, the conversion reactor may be a non-catalytic reactor or a catalytic reactor.

The working principle of the invention is as follows:

the supplemented carbon dioxide and hydrocarbon gas are compressed and heated, then enter a desulfurization system to remove sulfide, then are mixed with carbon dioxide and hydrogen returned by the system, enter an ejector to eject reformed gas circulation, and enter a reforming reactor after being mixed with the reformed gas, oxygen is introduced to carry out carbon dioxide and hydrocarbon reforming reaction to obtain high-temperature reformed gas containing carbon monoxide and hydrogen, the high-temperature reformed gas enters a decarburization system I after being subjected to multi-stage heat recovery and cooled to normal temperature by a cooler, the carbon dioxide removed from the decarburization system I and the carbon dioxide removed from a subsequent decarburization system II are subjected to pressurized circulation, the reformed gas of the removed carbon dioxide is purified by a carbon monoxide extraction device through pressure swing adsorption to obtain carbon monoxide, the removed carbon monoxide reformed gas also contains part of carbon monoxide, and enters a conversion device to convert the rest most of carbon monoxide into carbon dioxide and hydrogen, then the gas enters a decarburization system II to remove carbon dioxide, the gas from which the carbon dioxide is removed enters a pressure swing adsorption hydrogen extraction device to be purified to obtain hydrogen, and the hydrogen is compressed and then returns to the cycle.

The invention adopts hydrocarbon carbon dioxide reforming technology, steam is not matched for reforming, steam consumption is saved, high-concentration carbon monoxide reformed gas is obtained, carbon dioxide generated by the system is fully recycled, and carbon dioxide is supplemented externally, thus realizing carbon emission reduction.

The method can change the product components according to requirements, and can provide high-purity carbon monoxide and high-purity hydrogen.

Any feature disclosed in this specification may be replaced by alternative features serving equivalent or similar purposes, unless expressly stated otherwise. That is, unless expressly stated otherwise, each feature is only an example of a generic series of equivalent or similar features.

Example 1:

the flow of the synthesis gas obtained by the conversion of hydrocarbons in this example is as follows:

the flow is shown in FIG. 1. In this example, the hydrocarbon feed gas was natural gas, which came from a natural gas pipeline network at a flow rate of 3000Nm³H, temperature is normal temperature, pressure is 0.8MPa (G). Plus 600Nm³The carbon dioxide is discharged by other projects, the temperature is normal temperature, and the pressure is 0.8MPa (G). The carbon dioxide in the feed gas was 16.7% (mol%) of the amount of natural gas. Firstly, the pressure is increased to 2.5MPa (G) by a compressor. The waste gas is subjected to heat exchange with reforming outlet gas through a preheater I, heated to 350 ℃ and then enters a desulfurization device for purification. Mixing desulfurized natural gas with carbon dioxide recovered by a decarbonizing device I and a decarbonizing device II and hydrogen recovered by a PSA hydrogen extraction device, guiding partial reformed outlet gas to an inlet of a reforming device by using an ejector to obtain reformed inlet gas, mixing the reformed inlet gas with 980 ℃ high-temperature reformed outlet gas by using low-temperature mixed gas, introducing the gas into the reforming device at the temperature of 750 ℃, reacting the converted inlet gas with oxygen in the reforming device, dividing the reformed outlet gas from the reforming device into two parts at the temperature of 980 ℃, guiding and returning one part of the high-temperature reformed gas as circulating gas by using the ejector to be mixed with hydrocarbon gas, and circulating the gas by using a compressor in the embodiment compared with the conventional processThe energy consumption of the machine is about 9.7kW, and simultaneously, because the circulating gas in the embodiment is hot gas, the disadvantage that the temperature needs to be reduced in the flow of a circulating gas compressor is avoided, and the heat can be saved by about 36kW in a conversion manner. Part of the high-temperature reformed gas passes through a steam generator to recover high-level heat and is by-produced at 4.0MPa (G) for about 20 t/h. Preheating raw gas by using a high-temperature reformed gas at the outlet of the steam generator through a preheater I, then heating and circulating carbon dioxide and hydrogen mixed gas through a preheater II, then sequentially entering a boiler water preheater, a decarbonizing device II reboiler II, a decarbonizing device I reboiler I and utilizing low-level heat, then cooling and entering the decarbonizing device I to recover first-level carbon dioxide, drying and PSA purifying carbon monoxide to obtain about 3600Nm of carbon monoxide³H is used as the reference value. And (3) carbon emission of the system 0, wherein all carbon is converted into carbon monoxide products and is sent out of a battery limit. And the gas obtained after PSA carbon monoxide purification is subjected to shift and decarbonization device II and PSA hydrogen extraction device to recover hydrogen and carbon dioxide. Compared with the prior art of converting to produce gas, the theoretical conversion rate of converting natural gas into carbon monoxide is 100%, and the system can achieve zero carbon emission. Meanwhile, the carbon dioxide can be discharged from the outside, so that the carbon dioxide discharge can be reduced by 0.94 ten thousand tons every year for other devices, and the steam consumption can be reduced by 4.6 ten thousand tons every year.

Example 2:

the flow of the synthesis gas obtained by the conversion of hydrocarbons in this example is as follows:

the flow is shown in fig. 2. In this embodiment, the hydrocarbon feed gas is a carbon dioxide-rich natural gas, such as a marine-derived natural gas. The hydrocarbon feed gas flow rate is 3000Nm³At normal temperature and 50KPa (G), wherein CO₂The content of 22% (mol%) is first increased to 2.5MPa (G) by means of a compressor. The waste gas is subjected to heat exchange with reforming outlet gas through a preheater I, heated to 350 ℃ and then enters a desulfurization device for purification. Mixing the desulfurized natural gas with carbon dioxide recovered by a decarbonizing device I and a decarbonizing device II and hydrogen recovered by a PSA hydrogen extraction device, guiding part of high-temperature reformed gas at the outlet of a steam generator to the inlet of a reforming device by using an ejector to obtain reformed inlet gas, mixing the reformed inlet gas with high-temperature reformed outlet gas at 650 ℃ from low-temperature mixed gas to enter the reforming device at 500 ℃, reacting the converted inlet gas with oxygen in the reforming device, and repeating the stepsThe temperature of the reforming outlet gas from the whole device is 850 ℃, the reforming outlet gas is divided into two parts, one part of high-temperature reforming gas is used as recycle gas, and is drained by an ejector and returned to be mixed with hydrocarbon gas, compared with the prior art that a compressor is used for circulation, the energy consumption of the compressor is saved by about 8.1kW in the embodiment, meanwhile, the disadvantage that the temperature needs to be reduced in the process of the recycle gas compressor is avoided because the recycle gas is hot gas in the embodiment, and the heat can be saved by about 18kW in a conversion manner. A part of the high-temperature reformed gas passes through a steam generator to recover high-level heat and by-produce 4.0MPa (G) at about 11 t/h. Steam generator export high temperature reformed gas preheats the feed gas through I preheater and then through II heating cycle carbon dioxide of preheater, hydrogen gas mixture, again gets into boiler water preheater in proper order, II reboilers II of decarbonization device, I reboilers I of decarbonization device and low level heat utilization after, the cooling gets into decarbonization device I and carries out one-level carbon dioxide and retrieve, through drying, PSA purification carbon monoxide, obtain about 3000Nm of carbon monoxide³H is used as the reference value. And (3) carbon emission of the system 0, wherein all carbon is converted into carbon monoxide products and is sent out of a battery limit. And the gas obtained after PSA carbon monoxide purification is subjected to shift and decarbonization device II and PSA hydrogen extraction device to recover hydrogen and carbon dioxide. Compared with the prior art of converting to produce gas, the theoretical conversion rate of converting natural gas into carbon monoxide is 100%, and the system can achieve zero carbon emission. The steam consumption is reduced by 3.8 ten thousand tons every year.

Example 3:

the flow of the synthesis gas obtained by the conversion of hydrocarbons in this example is as follows:

the flow is shown in fig. 3. In this embodiment, the hydrocarbon feed gas is a carbon dioxide-rich natural gas, such as a marine-derived natural gas. The flow rate of the hydrocarbon raw material gas is 3000Nm³The temperature is normal temperature, the pressure is 50KPa (G), and the content of CO2 is 22% (mol%). Plus 600Nm³The carbon dioxide is discharged by other projects, the temperature is normal temperature, the pressure is 0.1MPa (G), and the CO in the raw material gas is obtained after the carbon dioxide-rich natural gas and the carbon dioxide are mixed₂The content was 35% (mol%). Firstly, the pressure is increased to 1.8MPa (G) by a compressor. The waste gas is subjected to heat exchange with reforming outlet gas through a preheater I, heated to 350 ℃ and then enters a desulfurization device for purification. The desulfurized natural gas is recovered by the carbon dioxide and PSA hydrogen extraction device recovered by the decarbonization device I and the decarbonization device IIAfter hydrogen is mixed, partial reformed outlet gas is guided to an inlet of a reforming device by an ejector to obtain reformed inlet gas, the reformed inlet gas is mixed with 980 ℃ high-temperature reformed outlet gas by low-temperature mixed gas, the temperature is 750 ℃ and enters the reforming device, the reformed inlet gas is converted in the reforming device to react with oxygen, the temperature of the reformed outlet gas from the reforming device is 980 ℃ and is divided into two parts, one part of high-temperature reformed gas is used as circulating gas and is guided by the ejector to return to be mixed with hydrocarbon gas, and compared with the prior art in which a compressor is used for circulation, the energy consumption of the compressor is saved by about 8.9kW in the embodiment, and meanwhile, because the circulating gas is hot gas in the embodiment, the disadvantage that the temperature needs to be reduced in the flow of the circulating gas compressor is avoided, and the heat can be saved by about 22kW in the conversion calculation. A part of the high-temperature reformed gas passes through a steam generator to recover high-level heat and is by-produced at 4.0MPa (G) at about 8.5 t/h. Steam generator export high temperature reformed gas preheats the feed gas through I preheater and then through II heating cycle carbon dioxide of preheater, hydrogen gas mixture, again boiler water preheater, export reformed gas divides two strands of entering II reboilers of decarbonization device, I reboilers of decarbonization device I and low level heat utilization after, mixed cooling gets into decarbonization device I and carries out one-level carbon dioxide and retrieve, through drying, PSA purification carbon monoxide, obtain about 3700Nm carbon monoxide of carbon monoxide³H is used as the reference value. And (3) carbon emission of the system 0, wherein all carbon is converted into carbon monoxide products and is sent out of a battery limit. And the gas obtained after PSA carbon monoxide purification is subjected to shift and decarbonization device II and PSA hydrogen extraction device to recover hydrogen and carbon dioxide. Compared with the prior art of converting to produce gas, the theoretical conversion rate of converting natural gas into carbon monoxide is 100%, and the system can achieve zero carbon emission. Meanwhile, the carbon dioxide can be discharged from the outside, so that the carbon dioxide discharge can be reduced by 0.94 ten thousand tons every year and the steam consumption can be reduced by 3.5 ten thousand tons every year for other devices.

The invention is not limited to the foregoing embodiments. The invention extends to any novel feature or any novel combination of features disclosed in this specification and any novel method or process steps or any novel combination of features disclosed.