JP4438791B2 - Ammonia production method and apparatus - Google Patents

Description

  The present invention relates to an ammonia production method and apparatus, and in particular, ammonia can be produced with high efficiency by inexpensive process equipment using organic raw materials such as coal (including low quality coal such as lignite), biomass, and super heavy oil. The present invention relates to an ammonia production method and apparatus.

In recent years, various plants for producing ammonia have been constructed. Typically, a natural gas hydrocarbon raw material is used to produce a synthesis gas containing hydrogen and nitrogen, and the hydrogen and nitrogen are synthesized and reacted. To produce ammonia. FIG. 4 is a flow sheet showing an outline of an example. A hydrocarbon raw material a of natural gas (mainly methane CH ₄ ) is supplied to a steam reformer b, and mainly in the presence of steam, the following reaction formula I Reform.

CH ₄ + H ₂ O → CO + 3H ₂ (I)
Shift reaction (side reaction): (CO + H ₂ O ← → CO ₂ + H ₂ ) (II)

  Next, the reformed gas subjected to reforming is supplied to an autothermal reformer c (ATR = autothermal reformer), and the remaining hydrocarbons in the presence of air are reformed mainly by the following reaction formulas III and IV. Quality.

2CH ₄ + O ₂ → 2CO + 4H ₂ (exothermic reaction) (III)

CH ₄ + H ₂ O → CO + 3H ₂ (endothermic reaction) (IV)
Shift reaction (side reaction): (CO + H ₂ O ← → CO ₂ + H ₂ ) (V)

  Subsequently, the reformed gas is supplied to the shift reactor d whose temperature is controlled, and the carbon dioxide produced by the reaction of changing the carbon monoxide by the shift reaction V of the above formula to carbon dioxide is separated. As a result, most of the reformed gas is only hydrogen and nitrogen by the air supply, and ammonia is produced by supplying the hydrogen and nitrogen to the ammonia synthesis reactor e. The ammonia synthesis reactor e is generally operated so that the ratio of hydrogen to nitrogen (HN ratio) is about 3. A plant for producing ammonia using such a hydrocarbon feedstock such as natural gas is disclosed in Patent Document 1, for example.

  On the other hand, a gasified gas is produced by an oxygen gasification method (partial oxidation method) in which coal or coke is used as a raw material to react with oxygen and water vapor, and then hydrocarbons in the gasified gas are modified using a reformer. Patent Document 2 discloses a method for producing ammonia from the reformed gas thus obtained.

As a method for producing gasified gas by gasifying coal or the like, in addition to the oxidizing gasification method disclosed in Patent Document 2, a thermal decomposition method, a steam gasification method, and the like are known.
JP 09-165215 A Japanese Patent Laid-Open No. 60-011587

  When natural gas is used as the hydrocarbon raw material a for ammonia production as in the method of FIG. 4 and the method shown in Patent Document 1, the problem of natural gas depletion and natural gas are relatively expensive as raw materials. In addition, there is a problem that the apparatus becomes complicated and expensive because it is necessary to install the steam reformer b in front of the autothermal reformer c to reform the hydrocarbon.

On the other hand, in a method of first producing gasified gas by gasifying coal or the like and reforming the gasified gas to obtain a reformed gas for ammonia production, in the case of the thermal decomposition method, Since there is a problem that the gasification rate is low and the content ratio of hydrocarbon (CH ₄ ) in the gasification gas is high, a steam reformer is placed in front of the autothermal reformer c as in the case of FIG. There is a problem that it is necessary to provide b and the apparatus becomes expensive.

The present inventors conducted an experiment to measure the composition concentration of gas generated by pyrolysis gasification and steam gasification using the experimental apparatus shown in FIG. The experimental apparatus shown in FIG. 5 is charged from the upper part in a state in which the silica sand g is charged into the reaction vessel f and heated by the electric furnace h from the outside, and water vapor i or nitrogen gas j is introduced from the lower part and fluidized. A predetermined amount of coal k was charged at one time (not continuously charged), and the generated concentrations (Vol%) of various gases in the generated gasified gas l were measured.
The experiment was performed under the following conditions.
Coal: Brown coal (water 35%) 1.8g
Sand layer temperature: 830 ° C
In the case of steam gasification: steam supply rate 3.0 g / min
In the case of thermal decomposition: nitrogen gas supply amount 6 L / min

  As shown in [Table 1], the amount of hydrogen produced in pyrolysis gasification is as small as 33.28% and the total amount of hydrocarbons is as large as 17.5%, whereas the amount of hydrogen produced in steam gasification is large. Is as high as 60.37%, and the total amount of hydrocarbons is as small as 3.44%.

  As described above, in the steam gasification method, the gasification rate of the raw material is increased, and the hydrocarbon concentration in the gasification gas is lowered. In the oxygen gasification method shown in Patent Document 2, the gasification rate of the raw material is further increased. Since the hydrocarbon concentration in the gasification gas is reduced and the hydrocarbon concentration in the gasification gas is reduced, it is possible to reform the hydrocarbon in the gasification gas only by the self-thermal reformer c in FIG. It is preferable to use the steam gasification method or the oxygen gasification method because the installation of the steam reformer b provided in the front stage of the vessel c can be omitted and the productivity of ammonia production can be improved. I can say that.

  However, in the case of the oxygen gasification method shown in Patent Document 2, an air separator for producing oxygen to be supplied to the gasifier is required, but a large amount of oxygen is required for oxygen gasification. Therefore, it is necessary to install a very large air separator, which increases the installation cost of the large air separator and the operating cost of the large air separator, thereby increasing the production cost of ammonia. .

  The present invention has been made in view of the above circumstances, and provides an ammonia production method and apparatus capable of producing ammonia with high efficiency by inexpensive process equipment using organic raw materials such as coal, biomass, and super heavy oil. It is something to be offered.

According to the first aspect of the present invention, coal, biomass, superheavy oil and steam are supplied to a steam gasification furnace to generate gasification gas by steam gasification, and the generated gasification gas is mixed with steam and air. Hydrogen and nitrogen obtained by reforming hydrocarbons in the gasification gas with a thermal reformer and removing carbon components in the reformed gas from the autothermal reformer are supplied to the ammonia synthesis reactor. In the ammonia production method for producing ammonia,
The detected value of the hydrocarbon concentration of the gasification gas generated in the steam gasification furnace matches the set value of the hydrocarbon concentration that can be reformed by the autothermal reformer. It is an ammonia manufacturing method characterized by controlling supply_amount | feed_rate.

The invention of claim 2 is characterized in that the concentration of hydrocarbons in the gasification gas is controlled by the amount of steam supplied to the steam gasification furnace and the gasification temperature of the steam gasification furnace. Item 2. The method for producing ammonia according to Item 1 .

In the invention of claim 3 , the supply amount of air supplied upstream of the autothermal reformer is such that nitrogen is in a ratio of 3: 1 to hydrogen in the reformed gas introduced into the ammonia synthesis reactor. The method for producing ammonia according to claim 1 or 2 , wherein the air supply amount contains nitrogen.

According to a fourth aspect of the present invention, the air is previously separated into oxygen or oxygen-enriched air and nitrogen by an air separator, and the oxygen or oxygen-enriched air is supplied upstream of the autothermal reformer to be used for generating hydrogen. The nitrogen production method according to any one of claims 1 to 3 , wherein nitrogen is supplied upstream of an ammonia synthesis reactor to be used for ammonia synthesis.

A fifth aspect of the present invention, any claim 1-4, characterized in that the hydrocarbon concentration of the autothermal reformer with processable gasification gas is preferably 15% or less is 10% or less It is the ammonia manufacturing method as described in any one.

According to a sixth aspect of the present invention, the supply amount of steam supplied to the upstream of the autothermal reformer with respect to 1% by weight of gasification gas is 0.35 to 0.40% by weight, and the supply amount of air is 0.60 to 0.60. It is 0.70 weight%, It is an ammonia manufacturing method as described in any one of Claims 1-5 characterized by the above-mentioned.

The invention of claim 7 includes a steam gasification furnace for generating gasification gas by steaming coal, biomass, and super heavy oil , a steam supply means for supplying steam to the gasification gas, and air for the gasification gas. Supplying air supply means, self-heat reformer for reforming hydrocarbons in gasification gas in the presence of water vapor and air to generate hydrogen, and carbon removal means for removing carbon components in the reformed gas And an ammonia production apparatus comprising an ammonia synthesis reactor that produces ammonia using hydrogen and nitrogen derived from the carbon removal means ,
A hydrocarbon concentration detector for detecting the hydrocarbon concentration in the gasification gas at the outlet of the steam gasification furnace, and a hydrocarbon whose hydrocarbon concentration detection value of the hydrocarbon concentration detector can be reformed by an autothermal reformer A controller for controlling the amount of steam supplied to the steam gasifier by adjusting the steam supply means to match the concentration;
An ammonia production device characterized by comprising a.

The invention according to claim 8 is the ammonia production apparatus according to claim 7 , wherein the steam gasifier is a two-column gasifier.

The invention of claim 9, wherein the controller is to control the amount of steam supplied to the steam gasification furnace, according to claim 7 or 8, characterized in that so as to control the gasification temperature of the steam gasifier The ammonia production apparatus as described in 2. It is a manufacturing device.

The invention of claim 10 includes an air separation device for separating the air into oxygen or oxygen-enriched air and nitrogen, and supplies the oxygen or oxygen-enriched air separated by the air separation device upstream of the autothermal reformer. The ammonia production apparatus according to any one of claims 7 to 9 , wherein nitrogen separated by the air separation device is supplied upstream of the ammonia synthesis reactor.

The invention according to claim 11 is a heat exchanger in which the reformed gas at the outlet of the autothermal reformer is heat exchanged with the gasification gas at the inlet of the autothermal reformer to increase the gasification gas temperature at the inlet of the autothermal reformer. The ammonia production apparatus according to any one of claims 7 to 10 , wherein the ammonia production apparatus is provided.

The invention of claim 12, the steam gasification furnace outlet, a tar remover, and carbon dioxide remover, according to any one of claims 7 to 11 comprising the compressor sequentially It is an ammonia production apparatus.

According to the ammonia production method and apparatus according to claims 1 to 12 of the present invention, high gasification is achieved by steam gasification using relatively inexpensive organic raw materials such as coal, biomass, and super heavy oil. The steam reformer installed in the front stage of the self-heat reformer can be omitted by suppressing the hydrocarbon concentration in the gasification gas to a low level. In addition, since it is possible to omit the provision of a large air separator such as the oxygen gasification method, the equipment can be made inexpensive, and the high productivity of ammonia can be enhanced by the high gasification rate by steam gasification. Can play.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

  FIG. 1 is a flow sheet showing an outline of an example of an embodiment for carrying out the present invention. In the figure, steam is supplied together with an organic raw material M such as coal, biomass, and super heavy oil including low-grade coal such as lignite. The steam gasification furnace is configured to perform steam gasification.

  As the steam gasifier 1, a two-column gasifier 100 as shown in FIG. 2 can be used. A two-column gasification furnace 100 shown in FIG. 2 includes a fluidized bed combustion furnace 101 in which char and a fluid medium generated by gasification of the organic raw material M in the fluidized bed gasification furnace 102 are introduced from below. The fluidized bed combustion furnace 101 heats the fluidized medium by burning the char while the char and the fluidized medium are fluidized at a high speed by the air supplied to the lower wind box 103 by the air pipe 104 while moving upward. Reference numeral 105 denotes an auxiliary fuel pipe for supplying auxiliary fuel to the fluidized bed of the fluidized bed combustion furnace 101, and reference numeral 106 denotes a heat exchanger for heat recovery provided in the upper part of the fluidized bed combustion furnace 101.

  The upper part of the fluidized bed combustion furnace 101 is connected to a separator 108 made of a cyclone through a transfer pipe 107, and the separator 108 includes an outer cylinder 109 and an inner cylinder 110, and the transfer pipe 107 enters the outer cylinder 109. The exhaust gas containing the unburned char and the fluidized medium introduced in the tangential direction is centrifuged, the exhaust gas and the fine ash content are discharged from the inner cylinder 110, and the unburned char and the fluidized medium 111 having a coarse particle size are separated from the separator. The lower fluidized bed gasifier 102 is supplied to a lower fluidized bed gasifier 102 by a downcomer 112 connected to 108.

  The fluidized bed gasification furnace 102 includes an introduction unit 113 for introducing the fluidized medium 111 separated by the separator 108 and a gasification unit for gasifying the organic raw material M supplied from the raw material supply line 114 with the heat of the fluidized medium 111. 115, the introduction part 113 and the gasification part 115 are communicated in the fluidized bed 116 to transfer the fluid medium 111 from the introduction part 113 to the gasification part 115, the introduction part 113, the communication part 117 and the gas. The box portion 118 into which water vapor is formed over the lower portion of the gasification portion 115 is inserted, and the water vapor supply means 119 is connected to the box portion 118. In FIG. 2, the introduction part 113 and the gasification part 115 are separated by the communication part 117 because the increase in pressure caused by the gasification of the organic raw material M in the gasification part 115 causes a fluidized bed gasification furnace. This is to prevent the fluid medium 111 in 102 from flowing back to the separator 108.

The gasification gas 120 generated in the gasification unit 115 includes hydrogen (H ₂ ), carbon monoxide (CO), carbon dioxide (CO ₂ ), free of an inert gas such as air or nitrogen for fluidization, The gasified gas 120 is a gas in which hydrocarbons such as methane (CH ₄ ) and water vapor are mixed, and the generated gasified gas 120 is led from the discharge pipe 121 to the recovery unit 122 and is accompanied by the fine powder 123 entrained in the gasified gas 120. After being removed, it is led out from the inner tube 124. In addition, a part of the char and the fluidized medium that has not been gasified in the gasification unit 115 is circulated from the overflow pipe 125 to the fluidized bed combustion furnace 101 so that combustion and fluidization are performed again.

The gasification gas 120 generated in the steam gasification furnace 1 is led to the tar remover 2 shown in FIG. 1 and the tar is removed by water injection or the like, and then led to the carbon dioxide remover 3 to be absorbed. Thus, carbon dioxide (CO ₂ ) is removed, and then compressed by the compressor 4. At this time, carbon dioxide in the gasified gas 120 is removed by the carbon dioxide remover 3 and the volume of the gasified gas 120 is reduced, whereby the compression power by the compressor 4 is reduced.

  The gasified gas compressed by the compressor 4 is removed from the sulfur by the sulfur remover 5 and then heated to, for example, around 750 ° C. by the external heat type burner 7 through the heat exchanger 6 and the self-heat reformer 8 ( ATR = autothermal reformer).

  On the upstream side of the autothermal reformer 8, for example, at the outlet of the sulfur remover 5, there is provided a steam supply means 9 for supplying steam to the gasification gas, and at the outlet of the external heating burner 7, the gasification gas is supplied. An air supply means 10 for supplying air is provided, and the autothermal reformer 8 generates hydrogen from hydrocarbons in the gasification gas in the presence of water vapor and air. A VI (endothermic reaction) reaction is performed, whereby a reformed gas 11 mainly composed of hydrogen and nitrogen and partially containing carbon monoxide and carbon dioxide is generated.

The temperature of the reformed gas 11 at the outlet of the self-heat reformer 8 is increased to, for example, about 1000 ° C., and the high-temperature reformed gas 11 heats the gasified gas supplied with the water vapor by the heat exchanger 6. After that, it is supplied to the carbon component removing means 14. The carbon component removing means 14 has a high temperature / low temperature shift reactor 12 composed of a high temperature shift section 12a and a low temperature shift section 12c after being cooled by the cooler 12b, and converts carbon monoxide in the reformed gas into carbon dioxide. The carbon dioxide is converted into carbon, and further, the generated carbon dioxide (CO ₂ ) is removed by an absorption method or the like by a carbon dioxide remover 13 provided at the subsequent stage of the high temperature / low temperature shift reactor 12. ing.

Since the reformed gas exiting the carbon component removing means 14 still contains a small amount of carbon monoxide (CO), the reformed gas is supplied to the methane generation reactor 15 to generate methane from the carbon monoxide. Is done. Most of the reformed gas from the methane production reactor 15 is hydrogen and nitrogen, and is supplied to the ammonia synthesis reactor 16 to produce ammonia (NH ₃ ). The amount of methane produced in the methane production reactor 15 is very small and does not adversely affect the production of ammonia, but may be removed from the reformed gas if necessary.

  A hydrocarbon concentration detector 17 for detecting the hydrocarbon concentration in the gasification gas 120 is provided at the outlet of the steam gasification furnace 1, and the detected hydrocarbon concentration value 18 of the hydrocarbon concentration detector 17 is a controller 19. The controller 19 controls the steam supply amount supplied to the steam gasifier 1 by adjusting the steam supply valve 20 provided in the steam supply means 119. The controller 19 is preliminarily input with a hydrocarbon concentration 21 obtained by performing a test for obtaining a hydrocarbon concentration that can be reformed by the autothermal reformer 8. The hydrocarbon concentration detection value 18 from the hydrocarbon concentration detector 17 matches the set hydrocarbon concentration 21, that is, the hydrocarbon concentration 21 that can be reformed by the autothermal reformer 8 is maintained. The steam supply amount supplied to the steam gasification furnace 1 is controlled.

  The controller 19 may control the amount of steam supplied to the steam gasifier 1 and adjust the gasification temperature of the steam gasifier 1. As a method for adjusting the gasification temperature, the method for controlling the circulation amount of the fluidized medium circulating from the fluidized bed combustion furnace 101 to the fluidized bed gasification furnace 102 in FIG. A method of adjusting the amount of auxiliary fuel to be supplied can be used.

  Next, the operation of the illustrated example will be described.

  As shown in FIGS. 1 and 2, the steam gasifier 1 is supplied with an organic raw material M such as coal (including lower coal such as lignite) and biomass, and is also supplied with steam by a steam supply means 119. The steam gasification furnace 1 generates the gasified gas 120 by steaming the organic raw material M.

  The gasified gas 120 is led to the tar remover 2 to remove tar, and then led to the carbon dioxide remover 3 to remove the carbon dioxide, and then compressed by the compressor 4. At this time, carbon dioxide in the gasified gas 120 is removed by the carbon dioxide remover 3 and the volume of the gasified gas 120 is reduced, whereby the compression power by the compressor 4 is reduced.

  The gasified gas compressed by the compressor 4 is heated by an external heat burner 7 through a heat exchanger 6 after sulfur is removed by a sulfur remover 5 and supplied to an autothermal reformer 8 (ATR). The

  At this time, steam is supplied to the gasification gas at the outlet of the sulfur remover 5 upstream of the self-heat reformer 8 by the steam supply means 9, and air is supplied to the gasification gas at the outlet of the external heating burner 7. Since the air is supplied by the supply means 10, the autothermal reformer 8 generates hydrogen from hydrocarbons in the gasification gas in the presence of water vapor and air. Is done. Thereby, the reformed gas 11 mainly containing hydrogen and nitrogen and partially containing carbon monoxide and carbon dioxide is generated.

  The reformed gas 11 is supplied to the high temperature / low temperature shift reactor 12 through the heat exchanger 6. At this time, since the gasification gas 120 supplied to the self-heat reformer 8 is heated by the high-temperature reformed gas 11 (for example, 1000 ° C.) at the outlet of the self-heat reformer 8, the self-heat reforming is performed. The fuel consumption of the external heating burner 7 for heating to the required temperature (for example, 750 ° C.) of the gasification gas 120 supplied to the vessel 8 can be reduced.

The reformed gas 11 cooled by the heat exchanger 6 is temperature-adjusted to, for example, about 350 ° C. and supplied to the high-temperature shift unit 12a of the high-temperature / low-temperature shift reactor 12, and then, for example, about 200 ° C. in the cooler 12b. And is supplied to the low temperature shift unit 12c. At this time, the reaction of the left term of the shift reaction V is performed in the high temperature shift unit 12a, and the carbon monoxide in the reformed gas is converted to carbon dioxide by the reaction of the right term in the low temperature shift unit 12c. . Subsequently, the reformed gas is guided to the carbon component removing means 14 and carbon dioxide is removed by an absorption method or the like. Since a small amount of carbon monoxide remains in the reformed gas that has passed through the carbon component removing means 14, the reformed gas is supplied to the methane generation reactor 15 to generate methane from the carbon monoxide. Since the reformed gas taken out from the methane production reactor 15 is mostly hydrogen and nitrogen, it is supplied to the ammonia synthesis reactor 16 to produce ammonia (NH ₃ ).

  As described above, the autothermal reformer 8 performs reforming to generate hydrogen from hydrocarbons in the gasification gas in the presence of water vapor and air, but is contained in the gasification gas 120 that can be processed. There is a limit to the concentration of hydrocarbons. Therefore, the components of the gasification gas 120 produced in the steam gasification furnace 1 can be adjusted so that the concentration range of hydrocarbons that can be processed by the autothermal reformer 8 is shown in FIG. It can be omitted to install the steam reformer b before the self-heat reformer c.

  For this reason, the hydrocarbon concentration in the gasification gas 120 at the outlet of the steam gasification furnace 1 is detected by the hydrocarbon concentration detector 17, and the hydrocarbon concentration detection value 18 of the hydrocarbon concentration detector 17 is converted into the self-thermal reforming. A hydrocarbon concentration 21 obtained by conducting a test for obtaining a reformable hydrocarbon concentration in the vessel 8 is inputted to the controller 19 which has been inputted in advance. Therefore, the controller 19 is a hydrocarbon that can be reformed so that the detected hydrocarbon concentration value 18 from the hydrocarbon concentration detector 17 coincides with the set hydrocarbon concentration 21, that is, the autothermal reformer 8. The amount of steam supplied to the steam gasifier 1 is controlled so that the concentration 21 is maintained. Control is performed by increasing the water vapor supply amount to decrease the hydrocarbon concentration and decreasing the water vapor supply amount to increase the hydrocarbon concentration.

  The hydrocarbon concentration in the gasification gas that can be processed by the autothermal reformer 8 varies depending on the performance of the autothermal reformer 8, various external conditions, etc., but stable operation can be performed in this type of plant. Since the possible hydrocarbon concentration is usually 15% or less, the hydrocarbon concentration 21 set in the controller 19 is 15% or less, preferably 10% or less. Here, when the amount of steam supplied to the steam gasification furnace 1 is increased, the loss of heat energy for heating the steam to the reaction temperature of, for example, 830 ° C. in the steam gasification furnace 1 is increased. The hydrocarbon concentration in 120 is preferably set to a value close to the upper limit of the hydrocarbon concentration that can be processed by the autothermal reformer 8.

  The controller 19 controls the amount of steam supplied to the steam gasification furnace 1 and the circulation amount of the fluidized medium circulating from the fluidized bed combustion furnace 101 to the fluidized bed gasification furnace 102 in FIG. The gasification temperature may be adjusted using a method or a method of adjusting the amount of auxiliary fuel supplied to the fluidized bed combustion furnace 101 by the auxiliary fuel pipe 105.

  The amount of air supplied by the air supply means upstream of the autothermal reformer 8 is such that the ratio of nitrogen to hydrogen in the reformed gas 11 introduced into the ammonia synthesis reactor 16 is 3: 1. Adjust to an air supply containing nitrogen. Thus, stable ammonia production is performed in the ammonia synthesis reactor 16.

When the present inventors tested the case where the hydrocarbon concentration in the gasification gas 120 was adjusted to 6%, 1 wt% of the gasification gas was supplied upstream of the autothermal reformer 8. A reformed gas of H ₂ / N ₂ = 3 suitable for ammonia synthesis when the supply amount of water vapor is 0.35 to 0.40 wt% and the supply amount of air is 0.60 to 0.70 wt% Could be obtained stably.

FIG. 3 shows another embodiment of the present invention. In the configuration shown in FIG. 1, the air supplied upstream of the autothermal reformer 8 is supplied to the air separator 22 in advance to supply oxygen (O ₂ ) or oxygen-enriched air and nitrogen (N ₂ ) are separated, and oxygen or oxygen-enriched air is supplied to the upstream of the autothermal reformer 8 to generate hydrogen, and nitrogen is an ammonia synthesis reaction. By supplying it upstream of the vessel 16 or upstream of the methanation reactor 15, it is used for the synthesis of ammonia.

  In the form of FIG. 3, air is separated into oxygen or oxygen-enriched air and nitrogen by the air separator 22 and supplied, so that the ratio of hydrogen and nitrogen supplied to the ammonia synthesis reactor 16 is adjusted. Therefore, the degree of freedom of adjustment can be increased.

  Note that the air separator 22 used here may be a small-scale apparatus capable of generating nitrogen necessary for ammonia synthesis in the ammonia synthesis reactor 16, and therefore, oxygen gasification as shown in Patent Document 2 described above. The size of the equipment can be reduced to about 1/4 to 1/5 that of the air separator in the case of the law, and thus can be implemented at low cost.

  As described above, in the ammonia production method and apparatus of the present invention, gasification gas is produced at a high gasification rate by steam gasification using relatively inexpensive organic raw materials such as coal, biomass, and super heavy oil. The steam reformer installed in the front stage of the self-thermal reformer can be omitted by suppressing the hydrocarbon concentration in the gasification gas to be low, and the oxygen gasification method Since it is possible to omit the provision of a large air separator such as the above, the equipment becomes inexpensive, and the productivity of ammonia is increased by using a device with a high gasification rate such as the two-column gasifier 100. be able to.

  Note that the ammonia production method and apparatus of the present invention are not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the present invention.

It is a flow sheet which shows an outline of an example of an embodiment which carries out the present invention. It is a schematic side view of the two tower type gasifier used as a steam gasifier of the present invention. It is a flow sheet which shows the outline of other examples of the form which carries out the present invention. It is a flow sheet which shows the outline of an example of the conventional which manufactures ammonia using natural gas. It is a schematic diagram of the experimental apparatus used for the experiment which measures the composition density | concentration of the gas which generate | occur | produces by the pyrolysis gasification and water vapor | steam gasification which the present inventors performed.

Explanation of symbols

1 Steam Gasification Furnace 2 Tar Remover 3 Carbon Dioxide Remover 4 Compressor 6 Heat Exchanger 8 Autothermal Reformer (ATR)
DESCRIPTION OF SYMBOLS 9 Steam supply means 10 Air supply means 11 Reformed gas 14 Carbon component removal means 16 Ammonia synthesis reactor 17 Hydrocarbon concentration detector 18 Hydrocarbon concentration detection value 19 Controller 21 Hydrocarbon concentration (setting)
22 Air Separator 100 Two-column Gasification Furnace 119 Water Vapor Supply Means 120 Gasification Gas

Claims (12)

Coal, biomass, super heavy oil and steam are supplied to a steam gasification furnace to generate gasification gas by steam gasification, and the gasification gas is mixed with steam and air and gasified by an autothermal reformer. Ammonia production method for producing ammonia by reforming hydrocarbons in gas and removing hydrogen and nitrogen obtained by removing carbon components in reformed gas from autothermal reformer to ammonia synthesis reactor In
The detected value of the hydrocarbon concentration of the gasification gas generated in the steam gasification furnace matches the set value of the hydrocarbon concentration that can be reformed by the autothermal reformer. A method for producing ammonia, comprising controlling a supply amount . The ammonia production according to claim 1 , wherein the concentration of hydrocarbons in the gasification gas is controlled by a supply amount of steam supplied to the steam gasification furnace and a gasification temperature of the steam gasification furnace. Method. The supply amount of air supplied upstream of the autothermal reformer is an air supply amount containing nitrogen in which nitrogen is in a ratio of 3: 1 to hydrogen in the reformed gas introduced into the ammonia synthesis reactor. The ammonia production method according to claim 1 or 2 , wherein The air is previously separated into oxygen or oxygen-enriched air and nitrogen by an air separator, and the oxygen or oxygen-enriched air is supplied upstream of the autothermal reformer to generate hydrogen, and nitrogen is an ammonia synthesis reactor. The method for producing ammonia according to any one of claims 1 to 3 , wherein the ammonia is supplied to the upstream of the gas and used for synthesis of ammonia. The ammonia according to any one of claims 1 to 4 , wherein a hydrocarbon concentration in the gasification gas that can be treated by the autothermal reformer is 15% or less, preferably 10% or less. Production method. The supply amount of steam supplied to the upstream of the autothermal reformer with respect to 1% by weight of gasification gas is 0.35 to 0.40% by weight, and the supply amount of air is 0.60 to 0.70% by weight. The ammonia production method according to any one of claims 1 to 5 , wherein: A steam gasification furnace that generates gasified gas by steaming coal, biomass, and super heavy oil; a steam supply means that supplies steam to the gasification gas; and an air supply means that supplies air to the gasification gas; Derived from a self-thermal reformer that generates hydrogen by reforming hydrocarbons in gasification gas in the presence of water vapor and air, carbon removal means for removing carbon components in the reformed gas, and carbon removal means In an ammonia production apparatus equipped with an ammonia synthesis reactor for producing ammonia using hydrogen and nitrogen produced,
A hydrocarbon concentration detector for detecting the hydrocarbon concentration in the gasification gas at the outlet of the steam gasification furnace, and a hydrocarbon whose hydrocarbon concentration detection value of the hydrocarbon concentration detector can be reformed by an autothermal reformer A controller for controlling the amount of steam supplied to the steam gasifier by adjusting the steam supply means so as to match the concentration;
Ammonia production apparatus characterized by comprising a. 8. The ammonia production apparatus according to claim 7 , wherein the steam gasification furnace is a two-column gasification furnace. The ammonia production apparatus according to claim 7 or 8 , wherein the controller controls the amount of water vapor supplied to the steam gasification furnace and the gasification temperature of the steam gasification furnace . An air separation device that separates the air into oxygen or oxygen-enriched air and nitrogen is provided. The oxygen or oxygen-enriched air separated by the air separation device is supplied upstream of the self-heat reformer and separated by the air separation device. The ammonia production apparatus according to any one of claims 7 to 9 , wherein nitrogen is supplied upstream of the ammonia synthesis reactor. A heat exchanger is provided that heat-exchanges the reformed gas at the outlet of the autothermal reformer with the gasified gas at the inlet of the autothermal reformer to increase the gasified gas temperature at the inlet of the autothermal reformer. The ammonia production apparatus according to any one of claims 7 to 10 . The ammonia production apparatus according to any one of claims 7 to 11 , wherein a tar remover, a carbon dioxide remover, and a compressor are sequentially provided at an outlet of the steam gasification furnace.

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