CN1043291A - Prepare ammonia by hydrocarbon-containing feedstock - Google Patents

Abstract

Adopt the part catalysed oxidn to produce ammonia by hydrocarbonaceous feed, its temperature and steam condition can produce synthetic gas and not have uncombined carbon; Adopt a kind of water-gas shift reaction that the carbon monoxide in the synthetic gas is converted to carbonic acid gas; Remove carbonic acid gas; Adjust hydrogen/nitrogen mol ratio between 2: 1 to 4: 1; Under the condition that produces ammonia, make the reaction of hydrogen and nitrogen.

Description

Prepare ammonia by hydrocarbon-containing feedstock

The present invention relates to prepare ammonia, comprise by one the method for raw material partial oxidation is made hydrogen-rich synthetic gas, then it is further handled and sends in the ammonia synthesis ring by hydrocarbon-containing feedstock.

Ammonia can prepared according to following reaction equation reaction in a so-called ammonia synthesis ring under the ammonia formation condition by hydrogen, nitrogen:

Hydrocarbon-containing feedstock is the hydrogen source that makes things convenient for that is used for ammonia synthesis such as the Sweet natural gas near the on-the-spot recovery oil field.Particularly, Sweet natural gas also has a small amount of ethane, propane and butane except containing main component methane, can also be the lower boiling liquid hydrocarbon in this external some conversion process.

For hydrocarbon-containing feedstock being changed into the hydrogeneous steam that can import in the ammonia synthesis ring, raw material at first is converted to the synthetic gas that contains a large amount of hydrogen and a small amount of carbon monoxide, carbonic acid gas and methane, the following endothermic side formula of the steam reforming process of methane:

Carry out the following Newton relation formula of the partial oxidation process of methane:

Carry out.The combination of another steam reforming and oxidation has been used to prepare synthetic gas.The steam reforming process reaction formula is compared fecund and is given birth to a moles of hydrogen with the partial oxidation process reaction formula.Steam reforming and/or partial oxidation produce synthetic gas can use a water-gas shift reaction

And the method for removing carbonoxide is handled with the hydrogen in the preparation input ammonia synthesis ring.

Usually comprise that in order to hydrocarbon-containing feedstock is changed into the method that synthetic gas adopts catalytic steam transforms, as above-mentioned reaction equation (2).In this process, hydrocarbon-containing feedstock is at catalyzer, normally under the existence of nickel-containing catalyst under the temperature between 1200 (650 ℃)-1900 (1040 ℃) and steam reaction.This is reflected in the furnace tubing that fills catalyzer and carries out.Hydrocarbon and steam react under these conditions and generate carbon monoxide and hydrogen.Catalytic steam conversion implementation cost is quite high, and not only nickel-containing catalyst is very expensive, and a large amount of heat absorptions of reaction, and therefore will carry out this reaction must provide big energy.

Thereby conversion reaction usually needs to provide air to provide energy to reduce the external heat demand with the partial oxidation by hydrocarbon in addition.The air conversion also can be used as second step of converting to be carried out, so that unreacted methane (methane " escape ") is reduced to one of percentage of volume ratio.After elementary steam converter flowed out, unreacted methane was transformed by the injection of air in the second steam convertor, this moment reaction heat by methane, the burning of hydrogen and carbon monoxide provides.Make it satisfy nitrogen demand in the ammonia synthesis ring by the combustion air input.Must from the output gas of secondary convertor, remove before entering ammonia synthesis ring the virose carbonoxide of ammonia synthesis catalyst.

Also can in an autothermic reactor, join autothermal reaction in steam and the hydrocarbon gas mixture and obtain in order to the synthesis gas preparation of ammonia synthesis with oxygenant (as: air).The heat that reaction is absorbed is provided by following thermopositive reaction:

The autothermal reaction implement body is made up of two catalyst beds, and first provides a sufficiently high temperature out for the steam reforming in second.In addition, reactant also can part transform in a steam reforming stove, enough enters autothermic reactor with the high-temperature that enters the oxygen spontaneous combustion with one then, thereby produce a high enough temp to transform in the adverse current catalytic bed.After thermal transition, carbonoxide is removed, thereby synthetic gas can be provided to ammonia synthesis ring, is generally carrying out under low through-put from thermal transition, and this process is to realize under 8000/ hour-12000/ hour the situation at space velocity." space velocity " may be defined as the volume of every catalyzer unit volume/hour (volume/hour) through-put rate.Here all numerals of being quoted are referring to the volume under the standard temperature and pressure condition/hour speed.

Above-mentioned can have following shortcoming in order to the synthetic gas production process of preparation ammonia: need expensive catalyzer, catalyst volume is big, and the speed of through-put is lower, and apparatus expensive needs space, excessive place under some situation; Need big energy again for making reaction carry out some situation.

The partial oxidation of hydrocarbon-containing feedstock is represented the another kind of method of steam reforming in the synthetic gas production.The commercial partial oxidation process of great majority all is a non-catalytic process.Yet the non-catalytic partial oxidation reaction effect is relatively poor.They must promptly need a large amount of oxygen at high-temperature under the temperature of 2200 (1200 ℃)-2800 (1500 ℃).Specifically, the ratio of oxygen and carbon was greater than 0.8: 1 in the non-catalytic partial oxidation reaction, and usually greater than 1: 1, partial oxidation also produces uncombined carbon in addition.

U.S. Pat .4390347(Dille at al.) disclosed the method that a kind of non-catalytic partial oxidation that utilizes liquid hydrocarbon containing fuels prepares synthetic gas.This hydrocarbon-containing feedstock is in the natural holding temperature that is in 1700 (930 ℃)-3000 (1650 ℃).There is down and contains the reaction of oxygen free gas in steam under the pressure of about 1-23 bar absolute pressure (1-23 crust).Described before the oxygen carbon mole ratio is from 0.7: 1-1.5: 1, and steam mixes with hydrocarbon stream with gentle temperature, and the carbon black of generation prevents to damage the refractory materials lining of producer, and also washs to remove uncombined carbon with water cooling.

U.S. Pat .No.3890123(Child at al.) disclose a kind of preparation method who is rich in steam methane in, wherein the non-catalytic partial oxidation of hydrocarbon-containing feedstock carries out when steam and oxygen exist.In the oxide compound in free oxygen and the raw material ratio number of carbon be 0.8: 1-1.5: 1.Carbon granule is removed from exhaust steam stream in the gas sweetening district.The synthetic gas of preparation carries out the water gas shift reaction again to increase the content of hydrogen in the gas.

U.S. Pat .No.3927998(Child et al.) relates to a kind of preparation method who is rich in methane stream, it is by the partial oxidation of hydrocarbon containing fuels, the weight ratio of steam and fuel is 2.2: 1-2.9: 1, and the mol ratio of oxygen and carbon is 0.8: 1-0.84: 1.Partial oxidation carries out in the presence of catalyst-free.This synthetic gas is cooled, and water, carbonoxide, carbon granule and other impurity all are removed.Hydrogen in the gas and carbon monoxide react the air-flow that is rich in methane with generation in a catalytic production of methane zone of action.

The transformation ratio of oxidising process generally can be improved by adopting catalyzer, but when oxidising process only part carry out, when promptly using insufficient oxygen complete oxidation hydrogen, catalyzer then is subject to the deposition and the blanking cover of carbon.

Yet, U.S. Pat, No.4087259(Fujitani et al) is disclosed in the method in and adopts rhodium catalyst, this method is vaporized liquid hydrocarbon-containing feedstock, then 690 °-900 ℃ temperature range, add selectively under the condition of steam as refrigerant with the speed that is not more than to wait 0.5 times of liquid hydrocarbon volume that water gauge shows, contact and partial oxidation with rhodium catalyst.Rhodium catalyst makes and carries out partial oxidation and do not produce carbon deposition, but in temperature during greater than 900 ℃, pyrolysis takes place and causes generating ethene or acetylene impurity.When steam adds fashionablely, make the hydrogen amount of generation increase simultaneously CO content and keep constant because of steam pyrolysis Cheng Qing and oxygen." LHSV " (liquid/hour space velocity) be the 0.5-25 liter/hour, particularly, is that 725 ℃ and LHSV 20 carry out at the gasoline vapour partial oxidation reaction of no steam in temperature, and the partial oxidation of carrying vapour is to be that 700 ℃ and 800 ℃ and LHSV carried out all can obtaining high hydrogen amount at 2 o'clock in temperature.

During catalysis conversion method in adopting prior art,, generally must adopt to be lower than 12000hr for obtaining a suitable conversion values ^-1Space velocity.U.S. Patent No. 4522894(Hwang et al for example) that has revealed a kind of preparation method of the hydrogen-rich gas as fuel-cell fuel in.This method makes to be imported one in the lump together with steam and oxide compound and uses in the autothermal reformer of two catalytic domains and react.This total per hour space velocity is between 1960hr ^-1-18000hr ^-1Between.Because the prior art method must be implemented under low spatial speed, existing catalyticreactor has to have a big catalytic bed to reach the required through-put of lot production.This has just increased the size and the expense of reactor.

A purpose of the present invention provides and a kind ofly prepares the method for ammonia by hydrocarbon-containing feedstock, and its energy-saving efficiency height can adopt low-cost catalyzer and less equipment volume and reaches enough large quantities of through-puts.

Another object of the present invention provides and a kind ofly prepares the method for ammonia by the meeting hydrocarbon feed, thereby only needs a less oxygen input to increase the flow of hydrocarbon-containing feedstock.

These and other purpose of the present invention can be achieved by the method for following narration.

The invention provides a kind of method for preparing ammonia, its rich hydrogenous synthetic gas is by hydrocarbon-containing feedstock, as Sweet natural gas, by oxygenant steam under the temperature and steam condition that do not produce uncombined carbon basically, with 20000hr ^-1-500,000hr ^-1Space velocity carry out the part catalyzed oxidation; The gained synthetic gas is handled with other composition except that dehydrogenation, nitrogen; Adjust the nitrogen amount of oxygen flow; And make hydrogen and nitrogen reaction generate ammonia.

In one embodiment, the invention provides a method for preparing ammonia by hydrocarbon-containing feedstock comprises:

(a) with hydrocarbon-containing feedstock, oxygen or oxygen-containing gas and in case of necessity steam elementary mixing completely gas mixture import in a part of catalyzed oxidation district, wherein the mol ratio number of steam and carbon is 0: 1-3.0: 1, the mol ratio number of oxygen and carbon is 0.3: 1-0.8: 1, described gas mixture to be lower than its spontaneous ignition temperature point but the temperature that is not less than 200 (93 ℃) input in the part catalyzed oxidation district.

(b) with hydrocarbon-containing feedstock in part catalyzed oxidation district, with be equal to or greater than the scope of being selected under the minimum non-carbonization temperature of 1600 (870 ℃)-1900 (1030 ℃), mutually should steam and the mol ratio number of carbon be equal to or greater than 0.4: 1-0: carry out partial oxidation by gas mixture by the catalyzer that can make hydrocarbon oxidation catalyst during 1 linear function, and generating the synthetic gas of hydrogeneous, carbon monoxide and carbonic acid gas, described gas mixture can 20000hr ^-1-500000hr ^-1Space velocity carry out partial oxidation catalysis, the geometrical surface of catalyzer is at least 5cm with the ratio of volume ²/ cm ³;

(c) synthetic gas is contacted under the aqueous vapor switch condition with a conversion catalyst and make carbon monoxide change into carbonic acid gas and hydrogen;

(d) remove carbonic acid gas in the air-flow;

(e) content of adjusting nitrogen in the above-mentioned not carbonated air-flow is to obtain between about 2: 1-4: the hydrogen nitrogen mol ratio number between 1;

(f) hydrogen in the adjusted air-flow and nitrogen are reacted under the ammonia formation condition and generate ammonia.

Below in conjunction with accompanying drawing the present invention is described in detail, wherein:

Fig. 1 is the partial oxidation reactor sectional view, and it has a mixing tank and a divider reactant can be transported to the catalytic bed that is used for the inventive method in the ingress;

Fig. 2 is the local amplification view of mixing tank and divider among Fig. 1;

Fig. 3 is the vertical view that mixing tank and divider 1/4th are cut open among Fig. 1;

Fig. 4 is the upward view that mixing tank and divider 1/4th are cut open among Fig. 1;

Fig. 5 shows the mixing tank of typical section and the constructed profile of feeder among Fig. 1-2, represented the part of cutting open of this mixing tank and feeder.

Fig. 6 is an embodiment schema of ammonia method produced according to the present invention, and this method adopts air to remove denitrification as the oxygenant in the part catalyzed oxidation and before ammonia synthesis ring with low temperature process;

Fig. 7 is the schema that improves embodiment of similar Fig. 6, but it adopts pressure oscillating (swing) absorption method, adjusts nitrogen content before ammonia synthesis ring;

Fig. 8 is the another conversion embodiment of similar Fig. 6, but it adopts the oxygenation air in part catalyzed oxidation step, and does not adjust nitrogen content before ammonia synthesis ring;

Fig. 9 still prepares the schema of the another conversion embodiment of ammonia method for the present invention, adopt oxygen or oxygen rich gas as oxygenant in part catalyzed oxidation step to reduce cost;

Figure 10 is still the another conversion embodiment of similar Fig. 9, and design cuts down the consumption of energy;

Figure 11 is to be 400psig(2760kpa at pressure) time oxygen carbon mol ratio number of three different operating temperature and the graphic representation of steam-carbon mol ratio number;

Figure 12 is that pressure is 400psig.(2760kpa) time three different operating temperature the graphic representation of hydrogen-oxygen carbon mol ratio number (in the part catalytic oxidation product) and steam-carbon mol ratio number;

Figure 13 is that pressure is 400psig(2760kpa) time part catalyzed oxidation product in the graphic representation of methane volume % and steam-carbon mol ratio number;

Figure 14 is that pressure is 400psig(2760kpa) time part catalyzed oxidation product in the graphic representation of carbon volume % and steam-carbon mol ratio number;

Figure 15 is that pressure is 400psig(2760kpa) in product during three different operating temperature in hydrogen carbon monoxide total amount and the raw material mol ratio number of hydrogen, carbon total amount to the mol ratio number of steam-carbon;

Figure 16 is the detail flowchart according to the inventive method first part;

Figure 17 is the detail flowchart of the second section of Figure 16 method;

Method of the present invention can be in order to prepare ammonia by any gaseous state or low boiling hydrocarbon-containing feedstock. Particularly,, wherein mainly formed by following approximately: methane 93%, ethane 5%, propane 1.5%, butane and higher hydrocarbon 0.5% for mainly containing gas such as the natural gas of methane for the preparation of the gaseous state hydrocarbon-containing feedstock of synthesis gas.

Generally, the contained step of the inventive method is, with hydrocarbon-containing feedstock Partial Oxidation and generate synthesis gas without free carbon under temperature and aqueous conditions, processed the gained synthesis gas with the component except dehydrogenation, nitrogen (such as carbonoxide) and reclaimed carbon dioxide; Adjust the content of nitrogen in the hydrogen-containing gas streams and make the reaction of hydrogen nitrogen generate ammonia.

A concrete aspect of the present invention is to realize the reduction of cost and the minimizing of energy consumption by adopting Partial Oxidation to generate the initial forming gas that is used for the ammonia production process, this becomes possibility after finding following situation, it is Partial Oxidation, one be selected under the temperature of minimum non-carbon formation temperature of 1600 °F (870 ℃)-1900 °F of (1040 ℃) scopes when it is being equal to or greater than, as the linear function corresponding to the mol ratio number of steam/carbon, be equal to or greater than 0.4: 1-0: 1 than number scope in, and take space velocity as 20000hr^-1-50000hr ^-1When carrying out, on catalyst, basically do not produce the carbon deposition. The product of finding in addition the inventive method catalytic partial oxidation is hydrogeneous, CO and CO mainly₂; When oxidizing temperature is equal to or greater than this minimum temperature, need not to prevent as catalyst with rhodium the formation of blocking. For example dotted line 25 represents a linear function in Figure 11, the minimum partial oxidation temperature of corresponding expression is about 1900 °F (1040 ℃) when a steam/carbon mol ratio number is zero, and, ratio in steam/carbon is 0.4 o'clock, and corresponding lowermost portion catalytic oxidation temperature is about 1600 °F (870 ℃). Partial Oxidation and the situation that do not generate free carbon are in temperature and steam/carbon mol ratio number equals into or produce during greater than some point on this straight line preferably. In addition, lower minimum temperature can be known by inference by the linear function of straight line 25 expressions greater than 0.4 o'clock than number in corresponding steam/carbon.

In Partial Oxidation step of the present invention, be lower than feeding gaseous mixture autoignition temperature but be not less than under the inlet temperature of 200 °F (90 ℃) one, reactant gas is imported into the Partial Oxidation district, be in the catalytic bed, best, reactant gas is inputted with a temperature that is equal to or higher than gaseous mixture catalysis autoignition temperature. Reactant should mix before reaction fully. The reactant gas that mixes fully with proper temperature input will guarantee that partial oxidation reaction controlled by material Transfer, and therefore, reaction rate does not depend on the activity of catalyst very much, but depends on the surface to volume ratio rate of catalyst. People can adopt multiple material as catalyst, as long as these catalyst have required surface to volume ratio rate. Catalyst there is no need to have the special catalytic activity in order to steam-reforming. Even when its as one have suitable gabarit catalyst the time general consider that the material as catalyst also can impel the generation of synthesis gas, used " catalyst " word comprises this material here.

Can be understood the Partial Oxidation step by accompanying drawing. The Partial Oxidation district is the catalytic bed of reactor shown in " 28 " among Fig. 1 specifically. Reactor 28 comprises that an entrance mixes and dispenser 30, and it mixes raw material and distributes this mixture to the entrance of catalytic reactor section 32 with oxidant. In catalytic reactor section 32, raw material partial oxidation and generate a product, then the latter passes export department 34.

Reactor comprises a shell 40, it is made by structural metal and carbon steel, and fixing top 42, one insulating barriers 44 such as a usefulness bolt (not shown), for example be 2300 °F of (1260 ℃) BPCF ceramic fiber insulation layers, be fixed within shell 40 tops that comprise with top 42. The bottom of mixing section 30 in reactor section 32 and export department 34, is fixed with insulating barrier 46,48 and 50 inside the shell. Layer 46 is that a cast or suitable insulating materials are such as 2000 °F of (1090 ℃) ceramic insulation things. Layer 48 also is a pourable or suitable insulating barrier but contains 60% aluminium oxide to resist 3000 °F of (1650 ℃) high temperature. Internal layer 50 be a refractory material or suitable material layer such as with the alumina brick of 97% aluminium oxide of ceramic fixator or 97% to resist the interior environment of reactor.

One or more catalysis dishes 54 are contained in catalytic reactor section 32, and as shown in the figure, reactor comprises one and inserts in a series of dishes between the adjacent disc of two-phase by 58 on high-alumina ring. This Pan Duo is supported by a grid with high-alumina bar 56. One sample port 60 is opened in the lower end of reactive moieties and a pipe is arranged, and for example 309 type stainless steel tubes 62 extend in firing tray 54 bottoms to extract the product sample out.

Export department's 34 formations link to each other with a downstream thimble-tube boiler (not shown) and/or other process equipment links to each other.

Catalyst comprises high surface area material, but the catalysis hydrocarbon-containing feedstock makes it partial oxidation. The gabarit of catalyst provides a surface to volume ratio to be at least 5cm²/cm ³ Catalyst preferably has a geometric jacquard patterning unit surface and the ratio of volume to be at least 20cm²/cm ³ Although surface-to-volume ratio without strict upper bound, does not generally exceed about 40cm²/cm ³ If the catalyst gabarit has required surface to volume ratio, then the capable of choosing multiple material comprises the material that those general considerations have catalytic activity as catalyst.

Catalysis dish 54 can be to have the overall structure of honeycomb type cross-sectional configuration such as one, such suitable overall structure has industrial production, size is used less than the present invention, is used for the catalytic oxidation that the vehicle exhaust catalyzed conversion also is used as the catalytic combustion part of gas turbine or is used as waste vapour as structural substrates. Overall structure is an extrded material specifically, contains some closed channels along the structure length direction and consists of honeycomb. This passage generally is square and can be pressed into density up to 1200 passages/square inch cross section. Overall structure can be designed to by multiple material, comprising cordierite (Mg O/Al₂O ₃/SiO ₂), Mn/Mg O-cordierite (Mn-Mg OAl₂O ₃SiO ₂), mullite (Al₂O ₃/SiO ₂) mullite-aluminium titanate (Mullite aluminium titanate) (Al₂O ₃/SiO ₂-（Al，Fe） ₂O ₃/TiO ₂), zirconia-spinelle Zirconia Spinel(ZrO₂/MgO/Al ₂O ₃), spinelle Spinel(MgO/Al₂O ₃), aluminium oxide (Al₂O ₃) and Langaloy. Integer catalyzer can singly be comprised of above arbitrary material, although these materials itself do not have catalytic activity. Utilize honeycomb substrates, can obtain surface-to-volume ratio and reach 40cm²/cm ³Or higher. In addition, whole substrate can be with any known metal or metal oxide coated with oxidation catalyst activity. These metals comprise, for example, and palladium, platinum, rhodium, iridium, osmium, ruthenium, nickel, chromium, cobalt, cerium, lanthanum and their mixing. Other can also comprise in order to the metal that applies catalysis dish 54 metal of I A, II A, III, IV, V B, VI B or VII B family in noble metal (noble metal) and the periodic table of elements.

Catalysis dish 54 also structural filler material as being used for filling the material of adsorption tower. These packing materials generally comprise the ripple foil and closely twist in and form together self long and narrow conduit. Structural filler material can comprise corrugated metal sheet such as high-melting-point alloy, stainless steel, chromium, manganese, molybdenum and high-temperature material. These materials are available knownly apply the activated metal of oxidation reaction or metal oxide if required, as applying with palladium, platinum, rhodium, iridium, osmium, ruthenium, nickel, chromium, cobalt, cerium, lanthanum and mixing thereof.

Catalysis dish 54 also can be comprised of such as high-melting-point alloy or platinum guaze the woven wire of densification. If required, wire netting also available to the activated metal of oxidation reaction or metal oxide coated as applying with palladium, platinum, rhodium, iridium, osmium, ruthenium, nickel, chromium, cobalt, cerium, lanthanum and mixing thereof.

The surface-area of above-mentioned any catalyzer gabarit and volume ratio can be increased by following means; at first water-based soup compound (slurry) is applied its surface; this soup compound contains have an appointment 1wt% or metal still less or metal oxide particle; such as alumina particle or I A, II A, III, IV, V B, VI B or VII B family metal; and the coated surface high-temperature heat treatment adhered on the surface, but temperature is not high to making this surface sintering.Particles used a BET(Brunnauer-Emmett-Teller should be arranged) surface-area is greater than about 10m ²/ g is more preferably greater than about 200m ²/ g.

In the invention process process, hydrocarbon-containing feedstock, oxygen or oxygen-containing gas such as oxygenation air or other oxygen rich gas and in case of necessity steam three's gaseous mixture be transfused in the catalytic portions oxidation zone, the temperature during input is not less than 700 °F (93 ℃) but is lower than its catalysis spontaneous ignition temperature.And gaseous mixture preferably enters in the catalytic portions oxidation zone with a temperature that is equal to or greater than its catalysis spontaneous ignition temperature.The heat that reaction produces might the control response device reactant be entered and is in the reaction zone of the temperature that is lower than spontaneous ignition temperature slightly, because will provide essential energy with temperature of charge in the rising reaction zone with a substance transfer controlled way (mass transfer controlled mode).Yet in the case, generally need provide heat input in the reaction zone ingress, a for example available spark device or before the input reactant with reactor in contained thing comprise that catalyzer is preheated to a temperature that surpasses spontaneous ignition temperature together, with provocative reaction.When being away from 200 °F (93 ℃) if the temperature of charge of reaction zone ingress is lower than spontaneous ignition temperature, it is very unstable that reaction can become.

When reaction mixture enters the catalytic portions oxidation zone to surpass one of its spontaneous ignition temperature temperature, mixture is mixed transport to catalytic bed afterwards immediately, in other words, the mixture of hydrocarbon-containing feedstock and oxygen is preferably in the time that spontaneous combustion can postpone and transported to catalytic bed in the past.Certainly gaseous reactant is answered thorough mixing.In case reactant undercompounding then can reduce product quality and can cause overheated.Thereby one mixes and the reacting by heating thing has been delivered to reaction zone in enough short period of time appropriate device is drawn in Fig. 1-5 and in the patent application of awaiting the reply jointly (serial No.085159, applying date 1987.8.14. applicant J.D.Korchak.M.Munskr and J.H.Marfen) detailed description arranged fully in order to raw material and oxygen or oxygen-containing gas are mixed, distribute to provide.

Referring to Fig. 1, one of feeding gas promptly contains the hydrocarbon gas or oxygenous, by first inlet 66, passes top cover 42, and the latter and the charging awl that constitutes first Room tins 68 is communicated with and is admitted to inlet portion 30.Awl tube 68 supports 69 and is fixed in the top 42.Other air inlet then 70 is sent into inlet portion Room 72 30, the second between the inlet of upper chambers 68 and catalyzed reaction portion 32 by extend through shell 40 side openings and second inlet that is communicated with second Room 72.One ring 73 that is installed in the upper wall 75 central part branches of chamber 72 connects the lower rim of awl tube 68 hermetically, thereby makes the public wall body of wall body 75 formation one between last chamber 68 and following chamber 72.There is on one outer portion 74(chamber 72 simultaneously referring to Fig. 2,3), be bearing in the end face of flame retardant coating 50.The tube wall 76 that extends fire-resistant sleeve 50 is once arranged at the bottom of chamber 72, and the bottom of chamber 72 is made of a foundry goods 78.

Steam be directed among hydrocarbon-containing feedstock and oxygen or oxygen-containing gas one or both of in case of necessity.Gas makes that with relative proportion feeding reactor the mol ratio number of steam/carbon is 0: 1-3.0: 1 preferably 0.3: 1-2.0: 1, and oxygen/carbon mol ratio number is 0.4: 1 to 0.8: 1, preferably 0.45: 1-0.65: 1.

Reaction mixture preferably enters in the catalyzed reaction portion 32 to be equal to or greater than its spontaneous ignition temperature.The concrete ratio of dependent reaction thing, reactor operating pressure and catalyst system therefor, this temperature are generally between 550 (290 ℃)-1100 (590 ℃).Hydrocarbon-containing feedstock and steam were preferably mixing before 70 or 66 by entering the mouth and are being heated to 650 °F (340 ℃)-1200 °F (650 ℃).Oxygen or oxygen-containing gas such as air heating to 150 (℃)-1000 °F (650 ℃) and enter by another inlet 66 or 70.

Referring to Fig. 2,3 and 4, mixing and distribution device comprise some long tubes 80, and they have the upper end that is installed on chamber 72 upper walls 75.The upper end of tube chamber is communicated with last chamber 68.Manage 80 lower ends and be fixed on the member 78, hold on its tube chamber and the passage 84 that passes member 78 vertical formations to be communicated with.Aperture 86 be formed on pipe 80 the wall body with air-flow among the 72 guiding tube chambers 80 of chamber.Inlet 66 and 70 awl tubes 68, support 69 and make, and chamber 72, pipe 80 and chamber 78 are made by conventional high-temperature alloy or high temperature material by the protection against corrosion heating resisting metal of routine.

Pipe 80 number, internal diameter 90(see Fig. 5), the size and the quantity of aperture 86 in every pipe, thus be to select to make in pipe 80 according to the gas ingress rate and by 66,70 the pressure of entering the mouth to generate turbulent flow, its speed surpasses the backfire speed of gas mixture.Aperture 86 and pipe 80 bottoms are chosen as to be equal to or greater than to providing in the minor increment 92 of the opening part that enters branched bottom 84 and make enough from the chamber that 68 air-flows of Room 72 under turbulent-flow conditions mix required size fully.The size and the pipe range 94 of managing 80 internal diameters 90 are designed to generate enough pressure drops the gas that flow to reaction chamber from chamber 68, thereby the 68 enough even equal air-flows that flow by pipe 80 from the chamber are provided.Equally, the size of aperture 86 also select between making it to provide chamber 72 and managing in 80 relatively gas enter pressure in the inlet 70 and speed with enough pressure drops, flow through aperture to enter the airshed of pipe 80 enough even thereby make.

The generation type of the branched bottom 84 in the chamber 78 will make supplied gas speed reduce and produce along the uniform gas of catalyst inlet distributes.The cross section of branched bottom 84 increases downwards with it, i.e. angle 98(passage 84 wall bodies and pipe 80 straight wall angle) generally be equal to or less than about 15 °, and preferably be equal to or less than 7 ° so that reduce to greatest extent or avoid in shunting 84, generating vortex.This just guarantee the complete gas of elementary mixing with one near or surpass its spontaneous ignition temperature, but preferably be illustrated in figure 4 as annular, but other shape such as hexagonal, square etc. also be fine less than the shape that enters catalytic bed, branched bottom bottom within its spontaneous combustion time of lag.

The part catalytic oxidation is preferably in the catalyzed reaction portion 32 and carries out, and pressure is greater than 100Psig(690KPa) more preferably greater than 250Psig(1720Kpa).The part catalytic oxidation carries out with 1400 (760 ℃)-2000 (1090 ℃) temperature.

From the product gas of export department's 34 discharges contain hydrogen substantially, carbonoxide is CO and CO ₂, methane, water vapour and inert fraction (as nitrogen or argon) any and that raw material is imported in the lump.Trace C ₂-reach higher hydrocarbon may in product, occur.Here used " trace " means weight less than 0.1wt%.

Removing of carbonoxide

Because carbonoxide is CO and CO ₂Appear in the synthetic gas, they are deleterious to ammonia synthesis catalyst, so will be removed before synthetic gas enters ammonia synthesis ring.

The synthetic gas of discharging from part catalyzed oxidation district is cooled to 350 °F (170 ℃)-750 °F (400 ℃) with conventional heat change method

In the temperature, or in order to heat hydrocarbon and steam feed, heated oxidant air-flow, superheated vapour, in boiler, improve vapour stream temperature, preboiler water inlet or fully utilize it.

The first step of removing carbonoxide is that water-cyclostrophic moves reaction CO is changed into CO, and CO and water reaction generate carbonic acid gas and hydrogen.The water gas shift reaction is known, and also can purchase the suitable equipment of implementing this reaction on the market.The water gas shift reaction can divide two stages to carry out, and promptly a high temperature shifts and a low temperature shift.In this process, synthetic gas at first reacts with steam, temperature is 580 °F (300 ℃)-750 °F (400 ℃), pressure is about 15atm, (1520kpa)-40atm(4050kpa), then carry out low temperature shift, temperature is about 350 (175 ℃)-500 (260 ℃), pressure and is about 15atm(1520kpa)-40atm(4050kpa).In addition, water gas shift reaction also can one step, shifts in the still at low temperature ring-type, steam temperature reaction device and carries out.In this process, steam and synthetic gas are with about 350 (175 ℃)-500 (260 ℃) temperature, about 15atm(1520kpa)-40atm(4050kpa) pressure reaction down.Contain the carbon monoxide that is less than 0.5% volume by the air-flow of discharging in the water gas shift reaction zone.

By catalytic selective oxidation, the CO of all retentions can be converted into CO basically ₂In this process, air-flow by the discharge of water gas shift reaction zone is reduced to 100 (35 ℃)-250 (120 ℃) afterwards dispelling the heat with its temperature, react under catalyst action with air, this selected catalyzer can or not have under the oxidized condition of hydrogen the CO oxidation at a small amount of hydrogen.The catalytic selective oxidation process is being known in the art, and describes in detail in U.S. Patent No. 3210782 and No.3631073.On sale on the suitable equipment market of enforcement this method, be the equipment of " Selectoxo " as trade mark.

For the catalytic selective oxidation process, the CO of retention can use the known method methanation in addition.Yet every mole of CO will consume three mol of hydrogen because of methanation reaction, otherwise the hydrogen of this process consumption can be used in the ammonia synthesis ring.Moreover,, enter the cleaning requirement of methane content increase ammonia synthesis ring in the ammonia synthesis ring although methane is inertia in ammonia synthesis ring.

Any other all can be used for removing micro CO in order to the known method of removing CO from air-flow.

Change into CO at CO ₂Afterwards, CO ₂From air-flow, removed and reclaimed, for example gas is passed through a liquid adsorption medium adverse current, for example absorbed CO with known method ₂Salt of wormwood.Removing the commercial processing unit of carbonic acid gas can purchase, and for example trade mark is the product of Selexol Amine Guard and Benfield.These methods are that carbonic acid gas is higher at pressure, temperature makes other gas pass through substantially steadily than being absorbed under the low condition in a chemistry or the physical adsorption medium simultaneously.This chemistry or physical absorbent are introduced step-down regeneration in the low pressure still then.If the employing chemosorbent, carbonic acid gas is with a contrary vapour stream desorb.This carbon dioxide is got rid of from the top of revivifier and sorbent material is returned to adsorber to reclaim more carbon dioxide.

Adjust a nitrogen content

After carbonic acid gas was removed from air-flow, the nitrogen amount of then adjusting air-flow compared number so that a hydrogen/nitrogen that is fit to ammonia synthesis to be provided.The mol ratio number of general hydrogen/nitrogen is adjusted at 2: 1-4: between 1, be preferably 2.5: 1-3.5: 1 with synthetic ammonia.The appropriate device of any adjustment nitrogen content all can adopt.

When air or rich oxygen containing air during as the oxygenant in the part catalyzed oxidation step, the nitrogen amount from the synthetic gas that part catalytic oxidation district discharges generally is greater than the required molal quantity of ammonia synthesis, so nitrogen must be removed from air-flow.When oxygen or the gas that is rich in oxygen (770mole%) during as the oxygenant in the part catalyzed oxidation step, the synthetic gas of discharging from part catalyzed oxidation district just requires extra nitrogen amount synthetic in order to ammonia usually.

One of method of adjusting the air-flow nitrogen content is with low temperature separation process and removes denitrification.The gas low temperature separation process is a known method, and this moment, gas was according to its liquefaction temperature and separated.Market cryogenic separator on sale can be removed denitrification from air-flow.

In addition, the nitrogen amount in the air-flow can be adjusted in pressure oscillating absorption.Pressure oscillating absorption comprises under the high pressure adsorbs desiring to remove composition, then under low pressure carries out desorb.This method is to have two basic steps and promptly adsorb and the recirculation of desorb and carry out work.Because of some hydrogen is lost in the waste gas in regeneration stage, so be not that all hydrogen all are recovered.Yet, when the frequency of step in the selected above-mentioned circulation and order, hydrogen just can be reclaimed to greatest extent and product gas in the ratio of nitrogen/hydrogen can be controlled to provide a required ratio by strictness.

The regeneration of sorbent material is carried out with three basic steps: (a) adsorber is reduced to low pressure, the useless composition of some dischargings in this step by desorb; (b) sorbent material is cleaned to remove remaining component with product hydrogen under the low pressure condition; (c) adsorber is forced into standby adsorptive pressure again.The waste gas that adsorbs gradually during regeneration is collected in the waste discharge gas buffer cylinder then, just can make the usefulness of fuel then.

Pressure oscillating absorption also can be used for removing CO ₂, methane, steam and other trace impurity such as H ₂S.Therefore, the pressure oscillating adsorption unit can be used for both removing CO ₂Adjust the nitrogen amount of air-flow again.Low temperature separation process can be used to remove methane, but steam and final carbonic acid gas trace still must be removed with the step of separating.Be used for before ammonia synthesis, removing steam and CO ₂Appropriate method be that air communication is crossed market any molecular screen material on sale.

Ammonia synthesis

As previously mentioned, it is random removing methane, because methane is inert in ammonia synthesis ring, but preferably removes methane from air-flow.When other component outside hydrogen, the nitrogen removed and hydrogen/nitrogen than adjusted after, air-flow has been ready to enter ammonia synthesis ring.Any suitable usefulness so that hydrogen nitrogen reaction all can adopt with the method that obtains ammonia.Used basic ammonia synthesis derives from from so-called " Haber Bosch " method.In this method, air-flow circulates under pressure in system.Air-flow feeds in the reaction chamber that has heated in this circulation, contact with ammonia synthesis catalyst and reacts, and the gas that contains the ammonia product leaves reaction chamber then, and makes the ammonia condensing recovery.Unreacted gas is by a compressor recirculation and mix with air inlet before reentering reaction chamber.Ammonia synthesis reaction is at about 650 (340 ℃)-770 (410 ℃) temperature and about 80atm(8100kpa)-150atm(15200kpa) carry out under the pressure.

Hydrogen, nitrogen contact with traditional ammonia synthesis catalyst in ammonia synthesis ring and react, and suitable catalyzer comprises such as once or the iron catalyst of double excitation.The catalyzer reinforcer comprises Al ₂O ₃Separately or and K ₂The O combination; ZrO ₂Separately or and K ₂The O combination; Or SiO ₂Separately or and K ₂The O combination.

The various alternate embodiment of the inventive method also can be referring to Fig. 6-10 with further understanding.

Fig. 6,7,8 has represented three embodiment of the present invention, and the air that all adopts air or oxygen enrichment is to transform ammonification with hydrocarbon-containing feedstock.

According to the method shown in 6, hydrocarbon-containing feedstock at first can optionally be handled in sulfur removal step 100, so that sulfide is removed from raw material.Removing sulfide can be with any appropriate device as with zinc oxide absorption etc.Removed sulfide before the part catalyzed oxidation, this all is arbitrarily to carry out in arbitrary embodiment, exists because the part catalysed oxidation processes allows sulfide.Such as removing steps such as acid gas or pressure oscillating absorption, also can be used for removing the gasiform sulphur compound.

After the sulphur removal, raw material is in air, steam entering part catalyzed oxidation district, and the part catalytic oxidation just takes place in step 102.The discharge gas of hydrogeneous, methane, carbonoxide and nitrogen flows out this part catalyzed oxidation district and passes heat exchanger its temperature is reduced between 350 (175 ℃)-750 (400 ℃) at step 104 place with the temperature of about 1650 (900 ℃).

This gas is then changed into CO at this CO with water gas shift reactions steps 106 as previously mentioned through a water gas shift reactor ₂

Effusive air-flow to a heat exchanger 108 from the shift reaction district is reduced between 100 (38 ℃)-250 (120 ℃) at this gas temperature.This gas is then through a selective oxidation district, and the CO that retain this moment is changed into CO with aforementioned selective oxidation method at step 110 place ₂

Afterwards, this gas is removed CO ₂Step, air-flow contacts with adverse current liquid, and this liquid flows in step 112 CO ₂From said flow, remove.This CO ₂Recyclable and as commodity selling.From CO ₂The gas that flows out in the adsorber contains minor amount of water and CO ₂, can be in step 116 by air flow stream being crossed molecular sieve and removing.

After removing oxycarbide, the nitrogen content of gas is adjusted to the mol ratio of hydrogen and nitrogen between 2: 1 to 4: 1, preferably from about 2.5: 1 to 3.5: 1.Because among the embodiment of Fig. 6 explanation, application of air is an oxygenant in the step of part catalysed oxidn, nitrogen is removed from air-flow to obtain the ratio of needed hydrogen and nitrogen.Removing in the low-temperature separator of step 128 of nitrogen carried out.Methane all in the air-flow are also removed in this step basically.

Then air-flow be compressed (undeclared) to about 80 normal atmosphere (8100kpa) between 150 normal atmosphere (15200kpa) and enter ammonia synthesis ring 126, here hydrogen and nitrogen react in the presence of a kind of catalyzer to produce ammonia under system ammonia condition.

Fig. 7 has illustrated a kind of differentiation of Fig. 6 program with schematic form: after step 106 and 110 carbon monoxide change into carbonic acid gas, in the air-flow withstanding pressure swing adsorption of step 118 to remove the nitrogen of carbonic acid gas, methane, water vapour and a part.The air-flow that comes out from pressure oscillating absorption directly enters ammonia synthesis ring 126.Because the pressure oscillating adsorption can be removed carbonic acid gas all in the air-flow and water vapor basically, therefore needn't use co 2 removal step 112 or molecular sieve step 116 among this embodiment of the present invention.

Fig. 8 has illustrated one embodiment of the present of invention with schematic form, its use oxygen-rich air in catalyzing part oxidation step 102 as oxygenant.By the ratio of oxygen and air in the correct adjustment oxidant feed, thereby also adjust the quantity that enters the nitrogen in this program, just may not need to adjust the nitrogen content in the downstream.In order to obtain the required hydrogen and the ratio of nitrogen of producing ammonia, the air that is adopted in the part catalyzed oxidation step in the embodiments of the invention program that Fig. 8 illustrates with schematic form and the mol ratio of oxygen are between about 0.2 to 0.3.Owing to need in the downstream, not adjust the content of nitrogen during Fig. 8 implements, had better not swing adsorption by applying pressure, and remove the same sequential steps of carbonic acid gas and water vapor among application drawing 6 embodiment, just, applying step 112 sponges carbonic acid gas in a counter-current absorber, then remove the carbonic acid gas and the water vapour of trace in step 116 with molecular sieve.

Fig. 9 and 10 has illustrated the present invention two embodiment preferably with schematic form, they in the part catalysed oxidn of hydrogen carbon charging with oxygen or oxygen rich gas as oxygenant.These embodiment are favourable economically, because they reduce facility expense and/or the energy requirement that drops into.Referring to a kind of oxygen level at least as the what is called " oxygen rich gas " that is at this moment adopted is 70% gas, and best minimum oxygen level reaches 90%.Owing in part catalysed oxidn program, use the lotus amount that program front end nitrogen was removed or reduced widely to oxygen or oxygen rich air physical efficiency, thereby greatly reduced the volume of synthetic gas generation equipment and downstream adjustment equipment.And, the energy requirement condition of nitrogen importation catalyst oxidation reactor is also reduced or eliminated.Oxygen or oxygen rich gas (being applied in the part catalyzed oxidation program) also can take known technology to produce, as the low-temperature fractionation effect of air.

Fig. 9 can quite reduce the investment of equipment with graphic extension one embodiment of the present of invention.In this embodiment, sulphur preferably can be removed from hydrocarbonaceous feed in step 100, and after this, charging and steam and oxygen or oxygen rich gas enter foregoing part catalyzed oxidation district.The part catalysed oxidn takes place in step 102, produce hydrogeneous, carbon monoxide, carbonic acid gas, methane, a little or do not have the synthetic gas of nitrogen, promptly nitrogen content is less than 30%, most preferably less than 10%.

Behind heat exchanger 104, conversion gas reaction 106 and heat exchange 108, as previously mentioned, adjust nitrogen content in the air-flow with the mol ratio that reaches hydrogen and nitrogen from about 2: 1 to 4: 1, preferably from about 2.5: 1 to 3.5: 1, adopt the method for adding nitrogen.

Impurity comprises methane, carbonic acid gas, carbon monoxide and H ₂S removes in pressure oscillating absorbing unit 118.Adsorption bed removes pressure and uses these hydrogen that can improve to a certain extent at pressure oscillating adsorption step 118 of nitrogen desorb and reclaim.Part absorbed nitrogen and product hydrogen are with together and are gone forth.

From pressure oscillating adsorption step 118 tail gas discharged, contain carbon monoxide, carbonic acid gas, hydrogen, nitrogen, methane and water vapor, be admitted to the catalytic combustion unit of step 122.The temperature that enters catalytic combustion unit tail gas is that about 570 °F (300 ℃) are to 1100 °F (590 ℃).Catalyticcombustion carries out to 2 normal atmosphere (200kpa) at about 600 (316 ℃) to 1800 (980 ℃) and a normal atmosphere (100kpa), can reach about 8000hr ^-2To 500,000hr ^-1Space velocity.The main carbonated of gas and the water that come out from catalyticcombustion step 122, and a spot of nitrogen, methane and other inert substance, as argon.By a heat exchanger thereby gas cooling water is condensed from give vent to anger in step 124, thus recyclable carbonic acid gas in the air-flow, and as a kind of commodity selling of preciousness.

Mix the mol ratio that makes hydrogen and nitrogen from the product of giving vent to anger of pressure oscillating adsorption step 118 with the nitrogen of capacity and be raised to 4: 1 from about 2.1, preferably from about 2.5: 1 to 3.5: 1.Basically the gas compression of being made up of hydrogen and nitrogen is reacted under system ammonia condition at this hydrogen and nitrogen to greatly about 80 normal atmosphere (8100kpa) and 150 normal atmosphere (15200kpa) and enter ammonia synthesis ring 126, as previously mentioned, and to produce ammonia.

The one embodiment of the present of invention that illustrate Figure 10 adopt the embodiment of the suitable a small amount of of a utilization energy among the present invention to make hydrocarbonaceous feed transform ammonification.

After best sweetening process 100, hydrocarbonaceous feed and steam, oxygen or oxygen rich gas entering part catalyzed oxidation district 102, here they carry out the part catalysed oxidn, as previously mentioned,, carbonic acid gas, carbon monoxide, methane, a little nitrogen hydrogeneous in the synthetic gas or do not have nitrogen to produce.After heat exchange 104, reformed gas reaction 106 and heat exchange 108, as previously mentioned, thereby carbonic acid gas is removed at step 112 place, rely on and to sponge carbonic acid gas such as contact with a kind of reverse direction flow that contains liquid-absorbant, says when narrating the relevant situation of Fig. 6 as preceding.Carbonic acid gas from co 2 removal step 112 can reclaim and sell as a kind of costly commodity.

Put into the pressure oscillating resorber remove the product air-flow that step 112 comes out from carbonic acid gas, here remove and comprise methane, carbonic acid gas, carbon monoxide and H ₂The impurity of S.To adsorption bed decompression and the desorb of employing nitrogen, these hydrogen that can improve pressure oscillating adsorption step 118 reclaim, and a part of absorbed nitrogen is along with product hydrogen band goes forth.

In embodiment 10, a part is recycled to the catalyzing part oxidation district from the waste gas (tail gas) of pressure oscillating absorbing unit, and here they provide heat for reactant.Best, the waste gas between 50% to 80% carries out recirculation from the pressure oscillating absorbing unit, and its remainder is as fuel.The product hydrogen that comes out from pressure oscillating adsorption step 118 mixes the mol ratio that makes nitrogen and hydrogen between about 2: 1 and 4: 1 with enough nitrogen, be preferably between 2.5: 1 and 3.5: 1, compress this gas then and put into ammonia synthesis ring, here hydrogen and nitrogen are the reaction of step 126 place (producing under the condition of ammonia), as previously mentioned, produce ammonia.

Figure 16 and ammonia factory that adopts production of ammonia natural gas of 17 explanations.This technology adopts the technology of a similar Fig. 9 and has catalyzed oxidation step 102, heat abstraction step 104, carbon monoxide switch process 106, heat abstraction step 108, pressure oscillating absorption step 118, combustion step 122, and ammonia synthesis ring 126, as there, narrate.Natural gas feed is accepted at circuit 200, and by saturex 202, adverse current enters one from the adding in the superheated current of circuit 204, enters the top of saturex again.The purpose of saturex 202 is to make the Sweet natural gas water saturation, thereby the reduction program is to the requirement of steam.Mix to produce the mixture of needed steam and Sweet natural gas again and from the product in a tributary 208 of a high pressure steam jar 210 from the saturated inlet air flow of saturex 202.Mixture on this circuit 212 enters in the heater coil 213 on the well heater that has caught fire 214 again and goes to think that the part catalysed oxidn provides needed temperature.This well heater that catches fire is to the waste fuel fuel supplying of small part by circuit 216.The heating of catching fire is also heated the water inlet in the circuit 218, this water joins in the vapor can 210 and goes, and heating exists in the steam of circle in 221 to produce superheated vapour in the circuit 222 from jar 210 products of branch line, and this steam is used in the program, as driving turbocompressor.

Come the hot hydrocarbon program flow of auto-ignition well heater 214 to send into part catalyst oxidation reactor 28 a kind of then, as shown in Figure 1, be mixed into the catalytic reaction zone of reactor 28 here and from the oxygen of circuit 228, thus part catalytically oxidizing natural gas and produce synthetic gas.Come the synthetic gas in autoreactor 28 circuits 230 to use the current from high pressure steam jar 210 to cool off by a heat exchanger, purpose is that part is cooled off this program flow.Program flow from heat exchanger 232 by circuit 234, here and more, form a kind of charging that enters high temperature shift reactor 240 by circuit 236 vapor supplied.This program flow comes out afterwards, enters heat exchanger 244 by circuit 242 from the high temperature shift reactor, uses the current from vapor can 210 to cool off again at this.Come the program flow product of automatic heat-exchanger 244 further to use jet of water cooling from circuit 248, purpose is to form a kind of program flow 250 to enter low temperature conversion reactor 252.This high temperature shift reactor 240 and low temperature conversion reactor 252 have carried out water conversion reaction step 106, and the carbon monoxide in the program flow is converted to carbonic acid gas.Come the program air-flow 254 of autoreactor 252 to arrive separating tank 268 then, here water is removed from program flow by heat exchanger 256, circuit 258, heat exchanger 262, circuit 263, heat exchanger 264 and circuit 266.Purge flow 270 from the ammonia circle mixes with program flow in jar 268.The program flow 272 that produces from jar 268 is admitted to a pressure oscillating absorbing unit 274, here carbon oxides and other impurity is removed from program flow.

Nitrogen on the employing circuit 276 is with the desorption in the assisting pressure swing absorbing unit 274.And nitrogen feed stream in the branch line 278 and the product air-flow of forced draft absorbing unit 280 merge to form ammonia supplies air-flow 282, to enter the ammonia circle 126 of Figure 17.

From the condensation product of branch line 286 on the separating tank 268 enter branch line 288 usefulness bid farewell in order to and enter pump 290 to form 292 and 294 parts.292 parts and a kind of water outlet from saturex 202 mix, form cooling-water flowings 298 by heat exchanger 256 by pump 295 formed recirculation current.These current 298 are by heat exchanger 256 heating, for saturex 202 provides hot water influent stream.The remainder of the product 296 of saturex 202 is by outside circuit 304 dischargers.Condensation product 294 parts are mixed the input 250 that formation jet water stream 248 is used for cooling off the low temperature conversion reactor with hot water flow 302.

In ammonia production technique 126 shown in Figure 17, circle is supplied the influent stream 284 of gas by compressor 310, flash drum 312, water-cooled heat exchanger 314 compressors 316, flash drum 318 water cooling heat exchangers 320 and circuit 322 merge to form program flow 326 with ammonia circle recirculation flow 324 then.To circuit 334, this circuit links to each other with the charging of an interior heat exchanger of ammonia converter 336 by circuit 330 and heat exchanger 332 in these program flow 326 usefulness compressors 324 recirculation.After the heating, program flow listens 336 by circuit 338 and ammonia conversion in transmodulator 336, and here hydrogen and nitrogen react in the presence of a kind of catalyzer, and the product air-flow of a part is formed ammonia.The outlet of ammonia converter is by heat exchanger 342 on the circuit 340, uses current from groove 344 to carry out heat exchange and cools off.This program air communication is crossed circuit 346 to heat exchanger 332 after coming out from heat exchanger 342, thereby influent stream 330 is heated.Program flow is used recirculation flow 356 coolings from the ammonia condensing facility here then by circuit 348, water cooling heat exchanger 350, circuit 352 and heat exchanger 354.The air-flow of coming in enters a holding tank 364 from heat exchanger 354 by circuit 358 and overcooling portion 360 and 362, collects liquefied ammonia here.From holding tank 364, uncooled overhead product forms recirculation flow 356.Gaseous purge stream 270 proposes from air-flow 356.

The liquefied ammonia that holding tank 364 comes out enters an ammonia collection unit 368 by circuit 366, from being extracted into ammonia product line 372 with pump 370 here.374 and 376 parts of ammonia receptor provide ammonia stream with the ammonia in the condensable product stream for each cooling segment 360 and 362.In the ammonia receptor 368, the gaseous product of 376 and 374 parts is by compressor 380,382 and 384 compressions enter a heat exchanger 388 and a cooling ring withdrawer 390 by circuit 386, and the liquid coolant from circuit 392 is here sent into ammonia withdrawer portion 374 again.Flashed vapour condenser 394 receives the air-flow of a part and other cooling segment is returned to receiving unit 368 by circuit 396 from circuit 392.Turbine 385 drive compression machine 380,382 and 386.

Compare with present industrial technology, this employing is a kind of to contain the stream that the surpasses 70 molar percent oxygen part catalyzed oxidation technology as oxygenant, and as narration here, technology of the present invention has following advantage.

1) when comparing, can remove expensive steam reforming furnace and two wires reformer with general-purpose industrial technology.

2) compare with general partial oxidation effect, zmount of oxygen consumption is low.

3) when comparing with steam reformation, water consumption is low.

4) when comparing with part catalyzed oxidation technology, adopt air or enriched air to produce a kind of rich nitrogen or stoichiometry synthetic gas in the outlet of part catalyst oxidation reactor, cost is low.

5) when comparing with steam reformation circuit (being suitable for offshore operations especially), usable floor area requires low.

6) when comparing with universal industrial ammonia production technique and comparing the efficient height with the part catalysed oxidn of application of air or enriched air (contain and be less than 70 molar percent oxygen).

7) lower than all present industrial technology cost investments.

Following example further specifies the present invention of narration here, and still not in office where face limits the scope of the invention.

The example I

Sweet natural gas transforms synthetic gas in a part catalyst oxidation reactor, its structure is shown in figure one, and the inside comprises nine catalysis dishes 54, and the diameter of each dish is 30 inches (0.76cm), and thickness is 10 inches (0.25m).Dish is made by a kind of honeycomb lumpy cordierite material, the geometric form surface that has, and its surface-area is approximately 25cm ²/ cm ³A kind of high surperficial alumina layer is placed on the trichroite as a kind of upholder, is expanding the catalytic metal component of fine dispersion in the above.This catalytic metal component approximately be 50%(by weight) platinum and 50%(by weight) palladium.The space velocity of this catalyzer is 97,000hr ^-1

Sweet natural gas and vapor mixing, heating is 10 inches a inlet 66 by a diameter, at 400psig(2760KPa in different steam/carbon mol ratios) pressure input down.Air heating, be 8 inches inlets 70 by a diameter, at 410psig(2830KPa) the following input of pressure.The diameter of the bottom 76 of Room 72 is 27 inches (0.68m) and the diameter on top 74 is 36 inches (0.91m).261 pipes are arranged, its internal diameter is 0.5 inch (12.7m), its length is that six diameters are arranged on 20 inches (0.51m) every pipes is 0.123 inch (3.2m) hole 86, wherein four holes are arranged on 4 inches (0.102m) above places, the pipe end, uniform ring is around pipe, other two holes are located at 6 inches (0.152m) above places, the pipe end, relative position.It is conical that bottom parts 78 thick 5 inches (0.127m), channel part 84 are, and last diameter is 0.5 inch (12.7mm), and following diameter is 1.75 inches (44.5mm).Pressure in the chamber 68 and 72 is kept the same with the ingress substantially.

The temperature of hybrid reaction gas is 1100 °F (590 ℃).The consumption of Figure 11 declaratives catalyzed oxidation program oxygen, as the function of steam to carbon mol ratio, temperature of reaction is 1,600 °F (870 ℃), 1,750 (950 ℃) and 1,900 (1040 ℃), working pressure 400psig(2700KPa).From the chart consumption of oxygen of the present invention as can be seen, with oxygen carbon mol ratio is represented, be quite low, compare with present industrial partial oxidation technology.Dotted line in Figure 11 is represented the linear function of minimum temperature and for preventing the needed steam/carbon ratio of carbon laydown.

Figure 12 illustrates hydrogen in the product, as H ₂And the ratio of carbon monoxide, be 1,600 °F (870 ℃) as temperature of reaction, the function of the steam/carbon ratio of 1750 (950 ℃) and 1900 (1040).

Figure 13 and 14 illustrates the methane and the carbonic acid gas of % volume in the product respectively, is 1600 °F (870 ℃) as temperature of reaction, the function of 1750 (950 ℃) and 1900 (1040 ℃) steam/carbon ratios.

Figure 15 illustrates the effective H of this technology ₂Production, by H in the product ₂And total mol of carbon monoxide is divided by H in the charging ₂And total mol of carbon shows.

The example II

Following example narration adopts technology of the present invention (by Fig. 9 and 10 representatives) to produce ammonia from a kind of hydrocarbonaceous gaseous feed.

Use universal method hydrocarbonaceous feed is carried out desulfurization, its method depends on the type and the quantity of institute's sulfur-bearing in the charging.Desulfurization can be given heat (temperature is between 250 (120 ℃) and 750 (400 ℃)) hydrocarbonaceous feed easily earlier and absorb its sulphur compound and go into zinc oxide-be included in the one or more desulfurizers.

Adding in steam takes off over cure to this charging makes the ratio of steam/carbon be in 1.0 and 1.7 to 1.0.Steam can directly add or adopt the air inlet saturation method.The hot water of air inlet saturation method can provide with recovery heat easily, and this reclaims heat from the synthetic gas on the point in conversion reactor downstream.

In the well heater that catches fire, give hot parallel feeding to about 1100 °F (590 ℃), feed the part catalyst oxidation reactor, the oxygen of it and preheating here (contains at least 70 molar percent oxygen as oxygen-containing gas, its ratio is in charging between every carbon atom 0.5 and the 0.55 mol oxygen) mix, after this, just enter into partial oxidation catalyst and carry out above-mentioned reaction (3) and reach (4).The temperature out of partial oxidation reactor approximately is 1700 °F (930 ℃).From the giving vent to anger of reactor, reclaim heat, adopt boiler to produce steam, add more steam in the synthetic gas before, lead in the high temperature shift reactor (temperature is greatly about 700 (370 ℃)), here, according to aforesaid equation (4), more carbon monoxide has played reaction.Synthetic gas comes out and produces high-temperature steam boiler at second to be cooled to about 650 °F (340 ℃) when about 850 of the temperature from the high temperature shift reactor.Adopt a kind of quench water that the temperature of synthetic gas is reduced to 425 °F (220 ℃), it stands low temperature conversion (according to aforesaid equation (4)) to reduce carbon monoxide content and to increase hydrogen richness again at this.Employing is given hot water and is reclaimed heat in the exit of low temperature conversion reactor, in order to the vapo(u)rous hydrocarbonaceous feed.Employing is given heat and is reclaimed heat again except that mineral water, and this water feeds one and removes aerator as boiler feed water.Synthetic gas arrives about 100 °F (380 ℃) with water quench more then, and water of condensation is separated in a separating tank.

In the technology of Fig. 9 and 10, comprised two kinds of selectable operational paths, depended on that huge amount ground reduces capital investment and increases feedstock conversion.Fig. 9 has shown that huge amount ground reduces capital investment.In Fig. 9, remaining carbon monoxide, methane, water vapor and carbonic acid gas are done to remove from synthetic gas with pressure oscillating absorption, as mentioned above, and to obtain High Purity Hydrogen stream.Add the nitrogen that comes from air separation plant then to produce a kind of gas of hydrogeneous and nitrogen, its mol ratio is the molar hydrogen of every mol nitrogen 2.5-3.5.From the waste gas of pressure oscillating absorbing unit (tail gas) not only can be used as in the well heater that catches fire fuel but also can, as need the oxidizing gas stream of a carbonic acid gas (for example producing the downstream of urea) and a part to carry out catalyticcombustion, adopt a kind of oxide catalyst.Methane, carbon monoxide and oxygen change into carbonic acid gas, therefore, and water and go out air-flow just a carbonated, nitrogen and water vapor basically from catalyticcombustion.Adopt desuperheating water from this air-flow, to condense, be recovered to useful heat simultaneously again.Water is finally separated in a separating tank, obtains carbon dioxide gas stream.

Figure 10 illustrates the selection of top efficiency.At Figure 10, adopt habitual chemistry or physical adsorption technology that carbonic acid gas is reclaimed from synthetic gas, as previously mentioned.This carbonic acid gas can be made commodity selling.Utilize pressure oscillating adsorber 118 to produce a kind of flow of pure hydrogen then.The pressure oscillating absorption tail gas is mainly only hydrogeneous, carbon monoxide, nitrogen, methane and any surplus water steam and carbonic acid gas.The part of this gas is as the fuel of the well heater that catches fire, and remaining is as the charging recirculation of part catalyst oxidation reactor.Perhaps, it can be recycled to high temperature shift reactor or low temperature conversion reactor upstream certain a bit go.Go in the nitrogen adding purified hydrogen air-flow from air separation plant, every mol nitrogen adds 2.5 to 3.5 mol hydrogen, produces a kind of gas that is suitable for synthetic ammonia.

Synthetic gas must be compressed to about 100atm(10130KPa) just can be used for closing ammonia.Replenishing gas and circulation gas mixes in suction place of circle synthesis circulator.The most gas that leaves circulator gives heat at circle interchanger place, and later split gas becomes two strands.One, and injects between first and second of ammonia converter relaxing synthesis reaction temperature as quench gas.Another strand is the conversion air inlet and is preheating to temperature of reaction, adopts and leaves second give vent to anger and carry out heat exchange, at a heat exchange gas that is arranged in ammonia converter inside.

Leave giving vent to anger at a boiler internal cooling to 7 (13 ℃) of transmodulator at about 766 °F (408 ℃), this boiler improves high pressure steam, circle gas interchanger, circle cold gas, recirculating gas exchange gas and circle water cooler, feeds holding tank then.Uncooled gas takes out from the holding tank napex, gives heat in the recirculating gas interchanger, and then is recycled to the suction inlet place of circulator.From recirculating gas, take out a small amount of purge flow for fear of the quantity of in ammonia synthesis ring, piling up inert material.This purge flow is recycled to pressure oscillating absorbing unit upstream a bit, or is recycled to part catalyst oxidation reactor upstream.

Leave collector and in the ammonia receptor, pressure is reduced to normal atmosphere at the flat liquefied ammonia down of control.Ammonia flashes away with molten Jie's gas and separates with liquefied ammonia in the nitrogen susceptor, recompresses 240(psig again in three stage cooled compressed devices) (1650KPa).After leaving cooling compressor, with a large amount of ammonia of condensation, it is separated in the cooling ring receptor with the water quench flashed vapour.

Cool off flashed vapour to-14 (26 ℃) and the normal atmosphere part of getting back to receptor again with the ammonia of from the cooling ring receptor, releasing and further reduce ammonia content in the flashed vapour again.Be discharged to the high-voltage section of ammonia receptor from most of condensation ammonia of cooling ring receptor, operation press and temperature at 49psig(338KPa) and 33 °F (1 ℃).The high-voltage section of ammonia receptor is also as the flash drum of water cooler fs.Flashed vapour enters the 3rd compression stage of cooled compressed device from this position, liquid then is discharged into the middle pressure part of ammonia receptor, pressure 16psig(110KPa) and 0 of temperature (17 ℃).This part is as the flash drum of the water cooler second wound section.Entered for the second cooled compressed stage and liquid phase enters the low-pressure section of ammonia receptor, normal atmosphere ,-28 (33 ℃) from the flashed vapour at ammonia receptor middle pressure position.Product ammonia is from pumping into the normal atmosphere holder here.

The example III

The I, II, III of tabulating down list the mol of ammonia factory shown in Figure 16 and 17/hour, the parameter of molar percent and pressure, temperature, water/steam flow and heat exchange.Per hour mole number is pound-mol/hour (0.4536 kilogram mole/hour).The NH that this plant produced is 600 short ₃(544x10 ³Kg/day).

(form is seen this paper 29-34 page or leaf)

Owing to can carry out a lot of detailed change, improvement and changes for above-listed embodiment, on address by the theme of the present invention of description of drawings and can understand as described, but do not limited by them.

The table III

Parameter

The transmission of pressure and temp water/steam net heat is described

PSIG KPa °F ℃ LBS/HR KG/HR MMBTU/HR KCAL 10 ⁶/HR

Sweet natural gas 200 502 3,461 60 16

Saturation water 204 436 224 324,596 147234

Saturation water 206 350 2,413 385 196

Steam 208 1,155 524

Vapor can 210 1,550 10687

Program gas/steam 212 388 198

Heat exchanger 213 36.226 9.129

Fuel 216 5 34 105 41

Boiler Steam output 218 424 218

Heat exchanger 25.024 6.306

Super heating steam 222 1,500 10,342 900 482 97,422 44190

CPO gas opening for feed 226 330 2,275 1,100 593

Oxygen 228 570 3,930 400 204

CPO output 230 300 2,068 1,650 900

Heat exchanger 232 58.618 14.772

Program gas 234 787 419

Steam 236 37,179 16864

HT switches the feed mouthfuls 238 700 371

HT changes discharge port 242 279 1,924 850 454

Heat exchanger 244 17.056 4.298

Program gas 246 650 343

Water 248 228 109 17,186 7796

Switch the feed mouthfuls 250 425 218

Switch the feed mouthfuls 254 265 1,827 464 240

Heat exchanger 256 59.694 15.043

Program gas 258 290 143

Heat exchanger 262 23.339 5.881

Program gas 263 243 117

Heat exchanger 264 27.465 6.921

Program gas 266 105 41

Purgative gas 270 1,430 9,860 85 29

PSA opening for feed 272 255 1,758 105 41

Table III (continuing)

Parameter

The transmission of pressure and temp water/steam net heat is described

PSIG KPa °F ℃ LBS/HR KG/HR MMBTU/HR KCAL 10 ⁶/HR

Nitrogen 276 240 1,655 105 41

PSA output 280 240 1,655 105 41

Circle supplies 282 239 1648

Condensation product 288 23,828 10808

Pump 290 52,610 23863

Water 292 48,472 21986

Pump 295 276,124 125248

Water 294 4,138 1877

Water 302 267 131 13,050 5919

Water 304 480 217

Program gas 322 105 41

Program gas 326 88 31

Program gas 330 1,500 10,342 98 37

Heat exchanger 332 100.399 25.300

Sequencer 334 498 259

Transmodulator output 342 1,470 10,135 766 407

Heat exchanger 342 51.120 12.882

Program gas 346 556 291

Program gas 348 140 60

Heat exchanger 350 8.931 2.251

Program gas 352 105 41

Heat exchanger 354 15.977 4.026

Program gas 358 62 17

Cooling segment 360 15.903 4.007

Cooling segment 362 16.312 4.111

Holding tank 364 1,435 9,894 12-11

Receptor part 368 0 0-28-33

Receptor part 376 16 110 0-17

Receptor part 374 49 338 33 1

Product ammonia 372 50 345-28-33

Claims (17)

1, a kind of technology of producing ammonia from hydrocarbonaceous feed, it comprises: up hill and dale hydrocarbonaceous feed and a kind of oxygen-containing gas (its oxygen/carbon mol ratio scope be 0.3: 1 to 0.8-1) and water vapor (its steam/carbon mol ratio scope is 0: 1 to 3.0: 1) are mixed, be equal to or greater than minimum non-carbonization temperature (being chosen in 870 ℃ to the 1030 ℃ scopes) in temperature, this temperature is the linear function as steam/carbon mol ratio, to equate or greater than the ratio of the steam that is equivalent to 0.4: 1 to 0: 1 scope to carbon, space velocity is 20,000hr ^-1To 50,000hr ^-1In the scope, this mixture of part catalyzed oxidation, thereby produce a kind of hydrogen that contains, the synthetic gas of carbonic acid gas and carbon monoxide, make synthetic gas carry out a water-gas shift reaction carbon monoxide in the gas is converted to carbonic acid gas, carbonic acid gas is removed from synthetic gas, and the nitrogen content of adjusting in this gas is about 2: 1 to 4: 1 to obtain hydrogen/nitrogen mol ratio, makes the reaction of hydrogen nitrogen produce ammonia in a cover ammonia synthesis technology.

2, a kind of technology as being claimed in the claim (1), the oxygenant that wherein is used for the part catalysed oxidn includes the oxygen that surpasses 70 molar percents.

3, a kind of technology as being claimed in the claim (2), the oxygenant that wherein is used for the part catalysed oxidn includes the oxygen that surpasses 90 molar percents.

4, a kind of technology as being claimed in the claim (1), wherein water-gas shift reaction is to carry out in a tubular reactor, its reaction heat is by the regeneration vapor recovery.

5, a kind of technology as being claimed in the claim (1), wherein the removal of carbonic acid gas from synthetic gas is by air-flow and a kind of counter current contact that includes the carbon dioxide absorption medium are finished.

6, a kind of technology as being claimed in the claim (5), after wherein being to remove carbonic acid gas, thereby adopt pressure oscillating absorption to produce a kind of purified hydrogen stream, before synthetic ammonia, nitrogen is added this air-flow to obtain required hydrogen/nitrogen mol ratio with the component of removing in the air-flow.

7, a kind of technology as being claimed in the claim (5), wherein the used bed of this pressure oscillating absorption is to adopt nitrogen to carry out desorb.

8, a kind of technology as being claimed in the claim (6), wherein the part exhaust gas recirculation that produced of pressure oscillating adsorption is to part catalyzed oxidation step.

9, a kind of technology as being claimed in the claim (1), thus wherein adopt the pressure oscillating adsorption to remove the hydrogen stream that carbonic acid gas and other impurity produce a kind of purification, added nitrogen in the past to obtain required hydrogen/nitrogen mol ratio at synthetic ammonia.

10, a kind of technology as being claimed in the claim (9), the bed that is wherein adopted in the pressure oscillating adsorption comes desorb with nitrogen.

11, a kind of technology as being claimed in the claim (9), wherein the tail gas that is produced by the pressure oscillating adsorption is that catalyticcombustion falls, thereby has produced carbonic acid gas as a kind of combustion prod, and this carbonic acid gas is reclaimed.

12, a kind of technology of being claimed as claim (6), the purgative gas of wherein obtaining from ammonia synthesis technology a bit is recycled in the program flow in certain of pressure oscillating adsorption step upstream.

13, a kind of technology as being claimed in the claim (9), the purgative gas of wherein obtaining from ammonia synthesis technology a bit are recycled among the Cheng Huanliu in certain of pressure oscillating adsorption step downstream and go.

14, a kind of technology of producing ammonia from hydrocarbonaceous feed comprises:

(a) to an a kind of blended gaseous state hydrocarbon-containing mixture charging fully basically of part catalyzed oxidation district input, oxygen or a kind of gas that contains 70 molar percent oxygen at least and, randomly, steam, wherein the mol ratio of steam/carbon is 0: 1 to 3.0: 1, and oxygen/carbon mol ratio is 0.3: 1 to 0.8: 1, and this its temperature of mixture entering part catalyzed oxidation district is lower than its catalysis autogenous ignition temperature and is not less than 200 °F (93 ℃);

(b) in part catalyzed oxidation district the above-mentioned hydrocarbonaceous feed of partial oxidation producing a kind of methane that mainly contains, oxycarbide, the gas of hydrogen and steam adopts to make said mixture by a kind of catalyzer that can the catalysis hydrocarbon oxidation, this catalyzer has the 5cm of being at least ²/ cm ³The geometric jacquard patterning unit surface area and the ratio of volume, and have and be equivalent to 20,000hr ^-1And 500,000hr ^-1Between the cumulative volume of space velocity, thereby produce a kind of hydrogen that contains, the synthetic gas of carbon monoxide, carbonic acid gas,

(c) synthetic gas is contacted with a kind of conversion reaction catalyzer under conversion aqueous vapor reaction conditions, make carbon monoxide conversion carbonic acid gas;

(d) carbonic acid gas is removed from air-flow,

(e) in the high velocity air nitrogen content to obtain the hydrogen/nitrogen mol ratio between about 2: 1 to 4: 1;

(f) under production ammonia condition, hydrogen and nitrogen are reacted in air-flow.

15, a kind of technology of being claimed as claim (14), hydrogen/ammonia mol ratio was arrived between about 2.5: 1 to 3.5: 1 at a high speed before wherein hydrogen nitrogen reacted under producing the ammonia condition.

16, a kind of technology of from the hydro carbons gas that mainly contains methane, producing ammonia, this technology comprises:

(a) hydro carbons gas is mixed with steam and a kind of oxygen-containing gas, the mol ratio of steam/carbon in 0: 1 to 3.0: 1 category, oxygen/gas mol to the ratio of carbon atom in 0.3: 1 to 0.8: 1 category, provide thoroughly, under the uniform mixing condition, need not burning

(b) this hydro carbons-steam of oxidation-oxygen attitude mixture partly in a part catalyzed oxidation district with the catalyzer that can promote methane oxidation, it is 5cm at least that this catalyzer has ²/ cm ³The geometric jacquard patterning unit surface area to the ratio of volume, the volume of this catalyzer is to be enough to can produce 20,000hr ^-1To 500,000hr ^-1Space velocity in the category to be producing the synthetic gas that contains hydrogen, carbon monoxide and carbonic acid gas,

(c) contact with a kind of conversion reaction catalyzer at the following synthetic gas of water-gas shift reaction condition, make carbon monoxide and water convert carbonic acid gas and hydrogen to,

(d) from the stream that water-gas shift reaction produced, remove carbonic acid gas, and

(e) thus the hydrogen the air-flow that produces from above-mentioned co 2 removal step is produced ammonia with the nitrogen reaction producing under the ammonia condition.

17, a kind of technology as being claimed in the claim (16), wherein the partial oxidation effect is to carry out under such temperature: the temperature that is equal to or greater than a kind of minimum is selected between 870 ℃ to 1030 ℃, as steam/carbon mol ratio, be equal to or greater than the linear function in the category that is equivalent to 0.4: 1 to 0: 1.

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