Method of nitric acid production and an installation for production of nitric acid

IPC classes for russian patent Method of nitric acid production and an installation for production of nitric acid (RU 2248322):

C01B21/40 - Preparation by absorption of oxides of nitrogen

C01B21/26 - Preparation by catalytic oxidation of ammonia

Another patents in same IPC classes:

Method of nitric acid production and an installation for production of nitric acid / 2248322
The invention is dealt with production of nitric acid with the help of oxidation of ammonia by oxygen of the air and absorption of nitrogen oxides by water in installations with uniform pressure at the stages of oxidation of ammonia and absorption of nitrogen oxides. The method of production of nitric acid in the installations with uniform pressure at the stages of oxidation of ammonia and absorption of nitrogen oxides provides, that compression of the air up to a uniform terminal pressure is conducted continuously within one stage without intermediate cooling and after that the compressed and so heated air is divided into two streams, one of which intended for production of nitric acid is directed to be cooled with further mixing with ammonia, and another is fed directly into a fuel combustion chamber connected with a recuperation turbine. The design embodiment of the installation for production of nitric acid provides for usage in the gas-turbine plant as an air engine for compression of air of an axial-flow compressor mounted directly on a common shaft with the recuperation turbine, at which near the outlet of the air engine the line of a compressed air stream is divided into two parts, one of which intended for production of nitric acid is first connected with a compressed air cooler and then with a mixer of ammonia with air, and the second intended for incineration of fuel is directly connected with the recuperation turbine combustion chamber. Besides in the capacity of a the compressed air cooler they use a "boiling" economizer connected to a line of a feed water for a boiler-utilizer and with a vapor collector of the boiler-utilizer by a line of steam-and-water mixture. The line of the air intended for production of nitric acid is also connected through the reheater of ammonia with a nitric acid blowing column. The technical result is simplification of the method, decreased investments and specific consumption of fuel.

Catalyst and a method of conversion of ammonia / 2251452
The invention is pertinent to the field of chemical industry, in particular to production of a catalysts and processes of oxidation of ammonia in production of a weak nitric acid. The invention offers an ammonia conversion catalyst on the basis of the mixture of oxides of unitized structure and a method oxidation of ammonia in production of weak nitric acid. The catalyst represents a mixture of oxides of the over-all formula (A_xB_yO_3Z)_k (M_mO_n)_f, (N_wP_gvO_v)_r where: A - cation of Ca, Sr, Ba, Mg, Be, Ln or their mixtures; B - cations of Mn, Fe, Ni, Co, Cr, Cu, V, A1 or their mixtures; x=0-2, y=1-2, z=0.8-l.7; M - A1, Si, Zr, Cr, Ln, Mn, Fe, Co, Cu, V, Ca, Sr, Ba, Mg, Be or their mixtures; m=l-3, n=l-2; N - Ti, Al, Si, Zr, Ca, Mg, Ln, W, Mo or their mixtures, P - phosphorus, O - oxygen; w=0-2, g=0-2, v=l-3; k, f and r - mass %, at a ratio (k+f)/r=0-l, f/r=0-l, k/f = 0-100. The catalyst is intended for use in a composition of a two-stage catalytic system generated by different methods, also in a set with the trapping platinoid screens and-or inert nozzles. The technical result ensures activity, selectivity and stability of the catalyst to thermocycles at its use in two-stage catalytic system with a decreased loading of platinoid screens.

Method of initiating ammonia conversion reaction / 2253613
Proposed method is performed on reticular platinoid catalyst by passing the ammonia-containing gas mixture and oxygen-containing gas through it; local sections of catalyst surfaces are periodically heated to reaction initiating temperature by means of linear electric heating elements located directly on catalyst surface. Equivalent diameters of local sections of catalyst surface are selected between 1-5 of magnitude of external equivalent diameter of separate electric heating element; linear electric heating elements are connected to electric power source at duty factor from 20 to 1 s. Used as material for reticular platinoid catalyst are the following alloys: Pt-81, Pd-15, Rh-3.5 and Ru-0.5 mass-%; Pt-92,5, Pd -4.0 and Rh -3.5 mass-%; Pt-95 and Rh-5 mass-%; Pt-92.5 and Rh-7.5 mass-%. Initiating the ammonia conversion reaction by this method is performed in reactors for production of nitric and hydrocyanic acids and hydroxylamine sulfate.

Ammonia conversion process / 2276098
Invention relates to ammonia conversion processes based on two-step catalytic system, which can be employed in production of nitric and hydrocyanic acids and in hydroxylamine sulfate production. Process according to invention comprises passing gaseous ammonia- and oxygen-containing mixture through two-step catalytic system, wherein first downstream step is embodied in a wire catalytic grate stack and second step in one or several layers of block honeycomb material, ratio of second-step hydraulic resistance value to the first-step one exceeding 4. Catalytic system steps are spaced from each other by distance equal to at most 10 and preferably 0.5 to 2 effective thickness of block channel σ calculated in terms of formula σ=2(S/(πn)^1/2 (1-ε^1/2), wherein S represents honeycomb block cross-section area, n number of channels in block, and ε open surface of block. Spacing between the steps is achieved by positioning between them spacing layer of gas-permeable chemically inactive material having hydraulic resistance coefficient below 100, hydraulic resistance of the second step being calculated as summary value of hydraulic resistances of honeycomb and spacing layers.

Method and the device for supporting of the catalytic meshes in the burners for oxygenation of ammonia / 2284291
The invention is pertaining to the support system for catalytic meshes in the burners for oxygenation of ammonia and to the method of reduction of movement of the particulates of the ceramic substance caused by the thermal expansion. The support system consists of the catalytic meshes (1) and possibly, of the support sieves (2) which are supported by the ceramic filling agents placed in the burner box with metallic walls and the perforated bottom. The support structure (9) is attached to the metallic wall (4) and-or the outer part of the periphery of the bottom (5). The technical result of the invention is development of the support structure, which does not cause damage of the packet from the catalyzer during operation of the burner, and the development of the system preventing movement of the of the particulates of the ceramic substance.

Method of intensification of the installation for production of nitric acid / 2286943
The invention is pertaining to the method of intensification of the installations for production of the non-concentrated nitric acid and may be used for raising productivity of the installations for production of the non-concentrated nitric acid under pressure. The invention provides for creation of the excess pressure on the inlet of the air compressor by preliminary compression of the atmospheric air in the high-pressure fan. At that the heat of the compression process in the warm season of the year is withdrawn by the direct contact with the water at the inlet of the fan, and in the cold season the heat is used for heating, at that in full or partially excluding heating of the air in the preheater mounted to prevent the icing up of the guiding apparatuses of the air compressor. At the enterprises with the high degree of the air dusting or chemical pollution for the contact cooling of the air by water it is possible to use scrubbers-washers, which combine the functions of the air cooler and the purification device. The method is effective for the operating installations, in which as a result of the wear-out of the flow-through section of the air compressors and the gas turbines decreases not only productivity, but also the pressure in the system, and as the result of it the concentration of the nitric acid. The method allows to realize the intensification of the installations using already existed equipment due to the increased pressure in the system. Concentration of the nitric acid is not lowered, the degree of purification of the tailing gases is preserved, production cost and the specific consumption of the steam and the natural gas are reduced.

Platinoid mesh catalytic agent / 2294239
The invention is pertaining to the field of the chemical industry, in particular, to production of the nitric acid, nitric fertilizers, the cyanhydric acid, the nitrites and nitrates and to other productions of chemical products, where the flow sheet of production provides for the catalytic conversion of ammonia up to the nitrogen oxides with usage of the platinoid mesh catalytic agents. The platinoid mesh catalytic agent formed in the form of the catalytic package produced out of the layer-by-layer stacked wire catalytic meshes and weaved out of the wires with the diameter of 0.06-0.1 mm consisting of the alloys of platinum with rhodium, palladium, ruthenium and other metals of the platinum group differs that the catalytic package consists of two different in the geometry of the braiding types of the meshes sequentially alternating in the height of the package. At that the geometry of the braiding of the first type of the catalytic meshes is characterized by the number of the wires interlacing per 1 cm² in the interval of 1024-450, and the geometry of the braiding of the second type of the catalytic meshes is characterized by the number of the wires interlacing per 1 cm² in the interval of 400-200. The technical result of the invention is the increased conversion of ammonia and the decreased share of the platinoids included in the mesh catalytic agent production processes providing for the catalytic conversion of ammonia in the flow sheet of the chemical goods production.

N₂o decomposition catalyst in ostwald process / 2304465
Decomposition if N₂O under Ostwald process conditions at 750-1000°C and pressure 0.9-15 bar is conducted on catalyst, which comprises (A) support composed of α-Al₂O₃, ZrO₂, SeO₂, or mixture thereof and (B) supported coating composed of rhodium or rhodium oxide, or mixed Pd-Rh catalyst. Apparatus wherein N₂O is decomposed under Ostwald process conditions on the above-defined catalyst is also described. Catalyst is disposed successively downstream of catalyst grids in direction of stream of NH₃ to be oxidized.

Catalytic element for heterogeneous high-temperature reactions / 2318596
Invention relates to catalytic elements including ceramic contact of regular honeycomb structure for heterogeneous high-temperature reactions, e.g. ammonia conversion, and can be used in production of nitric acid, hydrocyanic acid, and hydroxylamine sulfate. Described is catalytic element for heterogeneous high-temperature reactions comprising two-step catalytic system consisting of ceramic contact of regular honeycomb structure made in the form of at least one bed constituted by (i) separate prisms with honeycomb canals connected by side faces with gap and (ii) platinoid grids, ratio of diameter of unit honeycomb canal to diameter of wire, from which platinoid grids are made, being below 20.

Method of obtaining oxide catalysts on a substrate / 2329100
Invention pertains to the method of obtaining porous substances on a substrate for catalytic applications, to the method of obtaining porous catalysts for decomposition of N₂O and their use in decomposing N₂O, oxidising ammonia and reforming methane with water vapour. Description is given of the method of obtaining porous substances on a substrate for catalytic applications, in which one or more soluble precursor(s) metal of the active phase is added to a suspension, consisting of an insoluble phase of a substrate in water or an organic solvent. The suspension undergoes wet grinding so as to reduce the size of the particles of the substrate phase to less than 50 mcm. The additive is added, which promotes treatment before or after grinding. A pore-forming substance is added and the suspension, viscosity of which is maintained at 100-5000 cP, undergoes spray drying, is pressed and undergoes thermal treatment so as to remove the pore-forming substance, and is then baked. Description is also given of the method of obtaining porous catalysts on a substrate for decomposing N₂O, in which a soluble cobalt precursor is added to a suspension of cerium oxide and an additive, promoting treatment, in water. The suspension is ground to particle size of less than 10 mcm. A pore-forming substance, viscosity of which is regulated to approximately 1000 cP, is added before the suspension undergoes spray drying with subsequent pressing. The pore-forming substance is removed and the product is baked. Description is given of the use of the substances obtained above as catalysts for decomposition of N₂O, oxidation of ammonia and reforming of methane with water vapour.

Method for production of nitric acid / 2248936
Claimed method includes ammonia catalyst oxidation and nitrogen oxides absorption from nitrous gas with water and nitric acid, wherein nitrogen oxides absorption in absorption unit is carried out by using mass-exchange elements having several absorbing zones with different surfaces. Ratio (n) of oxidized nitrogen monoxide (NO) and absorbed nitrogen dioxide (NO₂) in determined according to equation: lg n = (0.22-0.29)-0.0626 lg PNO_x, wherein PNO_x is partial pressure of nitrogen oxides in nitrous gas. According the invention it is made possible to increase absorption ratio and reduce nitrogen oxide content in exhaust gas up to 0.005 vol.%.

Method of modernization of an installation for production of nitric acid with its increased productivity / 2253614
The invention is pertaining to the field of chemical industry, in particular, to the method of modernization of installations of nitric acid production. The method of modernizing of installation of production of the nitric acid providing for oxidation of ammonia with the help of air under a rarefaction, compression of the cooled nitrous gases in a nitrose supercharger, an absorption of nitric oxides in a tower absorber under pressure of 3.5-4.0 kg / cm², expansion of the waste tail gases in the turbo-expander, consists in the fact that they increase the pressure of the nitrous gases at the inlet of the supercharger in the range from rarefaction up to the pressure of 1.02-1.05 kg / cm², by installing a new or an additional gas blowers on the lines of the ammonia - air mixture or the nitrous gases or by decrease of hydraulic resistance of apparatuses and devices of pipelines at absorption inlet of the nitrose supercharger. At a pressure increase at the inlet of absorption of the nitrose gasses supercharger by decrease of the hydraulic resistance of the apparatuses and pipelines before absorption of the nitrose supercharger the increase of productivity of the installation will be much lower (~ up to 8 %). The method ensures an increase of productivity of the installation using the existing equipment at addition of small investments, which pay off less than for 1 year (from 0.6 up to 0.8 of a year) due to decrease of specific consumptions of raw material and power and a significant decrease of the conditionally-permanent expenses. Simultaneously the method allows to increase concentration of nitric acid and a degree of absorption, that may achieve its maximum at addition of pressure systems.

Method of removing no<sub>x</sub> and n<sub>2</sub>o from nitric acid production residual gas

Method of removing no_x and n₂o from nitric acid production residual gas / 2259227
Invention aims at reducing concentration of NO_x and N₂O in residual gas and provides a method wherein residual gas escaping absorption column, prior to enter turbine, is passed through two consecutive steps first reducing NO_x content by catalytic reduction and then reducing N₂O content by decomposing it into nitrogen and oxygen on catalyst containing one or more iron-loaded zeolites at working pressure 4-12 bar. Molar ratio NO_x/N₂O in residual gas before second step lies within a range of 0.001 to 0.5.

Method of the non-concentrated nitric acid production / 2296706
The invention is pertaining to the method of production of the nitric acid and may be used in chemical industry in the power-engineering operational layouts of production of the nitric acid containing the recuperation and high-temperature gas-turbine aggregate with application of the low-temperature catalytic selective purification of the exhaust gases from nitrogen oxides. The method of production of the non-concentrated nitric acid includes production of the nitrogen oxides by ammonia oxidizing, their absorption by the water, the catalytic purification of the exhaust gases after absorption by recovery of the residual nitrogen oxides by ammonia, their heating before feeding into the gaseous turbine by interaction of the methane with the oxygen on the catalytic agent ensuring decomposition of the nitrous oxide till the residual content of 5÷60ppm. As the catalytic agent use the high-temperature manganese -alumina catalytic agent with the contents of the active component - Mn₂О₃ ≥ 10 mass % on the A1₂O₃ carrier at the volumetric speed of the flow of 15000-25000 hour^-1. The oxygen content in the exhaust gases after the absorption is maintained within the range of 2.9-3.5 volumetric %, the volumetric ratio _of СН₄/O₂ at the inlet of the reactor is within the range 0.37 - 0.48. The method ensures the high level of the ecological purity of the exhaust gases, reduces the consumption of the natural gas used for heating up of the purified exhaust gases up to the temperature of no less than 730°С.

Apparatus for producing nitric acid / 2415806
Invention relates to inorganic chemistry and apparatus for producing nitric acid. The apparatus for producing nitric acid has pipes for supplying nitrogen and oxygen, a gas mixer 3, a generator 7 with gas inlet 8 and outlet 9 nozzles, a gas-water mixer 11 and a heat exchanger 12. The gas mixer 3 and the generator 7, in which a high-temperature zone with a gas phase is formed by creating nanosecond cold plasma electric arc streamer discharges, form a generator unit 1. The gas-water mixer 11, heat exchanger 12, which is a cooler and circulating pump 15 form an absorption unit 2, which is in form of a circulation loop. The absorption unit 2 also includes a surge vessel 13 in which there is a concentrator 14, which serves to maintain balance of the working solution.

Method of producing nitric acid (versions) and plant to this end / 2470856
Invention relates to nitric acid production and may be used in chemical industry. Compressed air is fed into one stage of gas turbine unit. Portion of compressed flow is cooled down and directed for cooling recuperative turbine 10. Major airflow is cooled in plate-type heat exchanger in feeding heated water to recovery boiler 6 and/or in steam generator while produced steam is directed for evaporation of liquid ammonia and/or heating and deaerating chemical cleaned water. Major flow is divided into two flows. First flow is fed to mixing with heated gaseous ammonia while second flow is fed into vent column16. Ammonia is oxidised by air of first flow at catalyst. Nitrose gas is cooled in recovery boiler 6 with bypass adjustment of its feed for heating end gases in two stages. Nitrose gas is aftercooled by water to condense reaction moisture in two stages. Nitrose gas is absorbed by steam condensate or desalted water. Nitric acid is blown by second pre-cooled airflow and divided into two flow, one to be fed for nitrose gas oxidation and second one to be fed into vent column 16. End gases are heated, cleaned of nitrogen oxides at catalyst, heated in gar turbine combustion chamber 19 to recover energy of off-gases in recuperative turbine 10.

FIELD: chemical industry; production of nitric acid.

SUBSTANCE: the invention is dealt with production of nitric acid with the help of oxidation of ammonia by oxygen of the air and absorption of nitrogen oxides by water in installations with uniform pressure at the stages of oxidation of ammonia and absorption of nitrogen oxides. The method of production of nitric acid in the installations with uniform pressure at the stages of oxidation of ammonia and absorption of nitrogen oxides provides, that compression of the air up to a uniform terminal pressure is conducted continuously within one stage without intermediate cooling and after that the compressed and so heated air is divided into two streams, one of which intended for production of nitric acid is directed to be cooled with further mixing with ammonia, and another is fed directly into a fuel combustion chamber connected with a recuperation turbine. The design embodiment of the installation for production of nitric acid provides for usage in the gas-turbine plant as an air engine for compression of air of an axial-flow compressor mounted directly on a common shaft with the recuperation turbine, at which near the outlet of the air engine the line of a compressed air stream is divided into two parts, one of which intended for production of nitric acid is first connected with a compressed air cooler and then with a mixer of ammonia with air, and the second intended for incineration of fuel is directly connected with the recuperation turbine combustion chamber. Besides in the capacity of a the compressed air cooler they use a "boiling" economizer connected to a line of a feed water for a boiler-utilizer and with a vapor collector of the boiler-utilizer by a line of steam-and-water mixture. The line of the air intended for production of nitric acid is also connected through the reheater of ammonia with a nitric acid blowing column. The technical result is simplification of the method, decreased investments and specific consumption of fuel.

EFFECT: the invention ensures simplification of the method, decreased investments and specific consumption of fuel.

4 cl, 1 dwg

The invention relates to the production of nitric acid obtained by the oxidation of ammonia by oxygen and absorption (absorption) of nitrogen oxides with water in aggregates with uniform pressure on the stages of the oxidation of ammonia and absorption of nitrogen oxides. The scope of the invention are units with uniform pressure of 0.7-1.0 MPa and the compression of air in the compressor part of the gas turbine installation. In the gas turbine installation engine air compressor is the recuperation of the gas turbine, in which the expanding heated to high temperature exhaust tail gases after the stage of absorption, and heating is provided by burning fuel, mainly natural gas in the combustion chamber of the turbine by mixing the tail gas with flue gases from a combustion chamber of the turbine.

A method of producing nitric acid under the same pressure (see, for example, the monograph “the Production of nitric acid in the units of great power” edited Vmelilo, M.: Chemistry, 1985, p.94-208), in which atmospheric air is compressed to the final pressure 0,716 MPa in two stages of compression. Atmospheric air at the first stage of compression is compressed in the axial compressor to pressure 0,343 MPa and temperature 174°, then cooled to 42° in the water heat exchanger, after which it goes to the 2nd stage compression in Central iny compressor, where is compressed to 0,716 MPa, heated up to 135°. The compressed air is separated into two streams: the main production of nitric acid, not primary - for own needs.

A large part of the primary air flow is directed to the mixture with gaseous ammonia, the other, smaller part is used for purging of nitric acid and as an additional air absorption. In accordance with the balance of primary air flow to maintain the stage of oxidation of ammonia optimal temperature (900° (C)the air before mixing with ammonia fuel from 135 to 180-230°With nitrous gases. The air in the starting the combustion turbine is supplied at a temperature of 135°C.

A prototype of the proposed method of production of nitric acid obtained by the oxidation of ammonia by oxygen and absorption of nitrogen oxides with water in aggregates with uniform pressure on the stages of the oxidation of ammonia and absorption of nitrogen oxides, is the method described in “Handbook apothica”, ed. 2nd, book 2-I, M.: Chemistry, 1987, p.66-73.

The disadvantages of the known methods can be attributed to the presence of two stages of compression of the air, resulting in additional hardware required to implement the second stage of compression and intermediate cooling.

In the same sources of information (see “the nitric acid unit is x high power” Ed. Vmelilo, M.: Chemistry, 1985, p.94-208 and the Directory of apothica”, ed. 2nd, book 2-I, M.: Chemistry, 1987, p.66-73) describes the units for the production of nitric acid obtained by the oxidation of ammonia by oxygen and absorption of nitrogen oxides with water in aggregates with uniform pressure on the stages of the oxidation of ammonia and absorption of nitrogen oxides, comprising a gas turbine installation with an axial air compressor and gas turbine on the same shaft, the cooling coil, centrifugal blower, starting motor-generator and a multi-stage gearbox that transmits the power from the gas turbine for rotation of the centrifugal blower and the energy from the motor-generator with a capacity of 800 kW at the start and to the motor-generator in a stationary mode.

Complex design of the gas turbine installation dramatically complicates the operation of the unit especially because of the frequent failure of the cooler, gearbox. In addition, increases the cost of the resulting nitric acid due to the cost of repairs and spare parts and a long period of start gas turbines leads to excessive fuel consumption - natural gas.

The proposed invention solves the problem of considerable simplification of the received compressed air to the desired pressure due to the exclusion of the air cooler, centrifugal compressor, multistage re is octora, and thereby simplify the whole method and installation nitric acid production, reducing capital investment, improve equipment reliability, in addition, reduction in the consumption of cooling water and, as a consequence, the water cycle, as well as a reduction in specific fuel consumption.

To solve this problem and obtain such technical result in the proposed method of production of nitric acid obtained by the oxidation of ammonia by oxygen and absorption of nitrogen oxides with water in aggregates with uniform pressure on the stages of the oxidation of ammonia and absorption of nitrogen oxides in the air is compressed to a single final pressure carried out continuously in a single stage without intermediate cooling, and then compressed and thus heated air is divided into two streams, one of which is designed to produce nitric acid, direct the cooled and then mixed with ammonia, and the other is fed directly into the combustion chamber of the fuel associated with recovery turbine.

Distinctive features of the proposed method lies in the implementation of the compression of the air in one step without intermediate cooling and subsequent separation of compressed air into two streams, one of which is designed to produce nitric acid, direct the cooled and then mixed with ammonia, and the other is fed directly into the combustion chamber of the fuel, associated with recovery turbine.

The essential features of the claimed method can significantly simplify the process of obtaining compressed air, and the subsequent cooling of the main flow of the compressed air expands the supply of air for mixture with ammonia at the optimum temperature (above 180-230°C), especially at a pressure of 0.8-1.0 MPa with lower capital costs and with the best rates on specific steam production.

To solve this problem and achieve the mentioned technical result of the proposed design solution unit with the apparatus of the oxidation of ammonia by air, the absorption of nitrogen oxides, the gas turbine installation including a compressor for compressing air and heat recovery turbine for expansion of the tail gas, the heated gases from the combustion of fuel, as well as the heater and mixer ammonia, line feed water for a boiler having parosbornoj, and purge the column of nitric acid, in which the gas turbine installation as a compressor for compressing air used axial compressor mounted directly on the same shaft with recovery turbine, and whose output from the compressor line to the compressed air stream is divided into two parts, one of which is designed to produce nitric acid, include the first and with the cooler compressed air and then with a mixer of ammonia with air, and the second is designed to burn fuel directly to the combustor recuperator turbine. In addition, as the cooler compressed air used “boiling” economizer connected to the line of feed water for boiler and paromomycin boiler line steam-water mixture, and the air line designed to produce nitric acid, is connected to the purge column nitric acid through the heater ammonia.

In contrast to the known constructive solutions offers claimed as a compressor for compressing air to use axial compressor mounted directly on the same shaft with the recuperation turbine with the compressor outlet line of the compressed air stream is divided into two parts, one of which is designed to produce nitric acid, associated first with the cooler compressed air and then with a mixer of ammonia with air, and the second designed for burning fuel directly to the combustion chamber of the regenerative turbine. In addition, as the cooler compressed air is suggested to use the “boiling” economizer connected to the line of feed water for boiler and paromomycin boiler line steam-water mixture, and also the line, intended for the floor the treatment of nitric acid, to connect with the purge column nitric acid through the heater ammonia. As “boiling” of the economizer can be used in the economizer, is given in the publication, for example, “New Polytechnical dictionary”, edited by Wailing, M., 2000, p.80.

The essential features of the claimed design solutions unit can simplify the design. The use of “boiling” economizer allows you to utilize low-grade heat hot air in the unit of nitric acid with the greatest efficiency, as it provides an increase steam generation.

Thus, the technical solution according to the invention allow not only to compensate for the increased energy consumption for air compression in one step, but to get some reduction in fuel consumption per ton of nitric acid, also taking into account the exception of the coolant water flow of cooling air between steps.

The invention is illustrated in the drawing, which schematically shows the aggregate production of nitric acid.

A unit for the production of nitric acid includes filter atmospheric air 1, the axial air compressor 2, “boiling” economizer 3, the mixer 4, the contact device 5, boiler 6, with parosbornoj 7, the combustion of the fuel 8, associated with PE is operacionnoi turbine 9, the tail gas heater 10, the catalytic purification reactor 11, the cooler-condenser 12, an absorption column 13, the purge column 14, the ammonia gas heater 15, the starter motor 16 to start the recuperation turbine 9.

The proposed method is carried out in the following sequence: the air, such as air, passing through the filter 1, is fed to the absorption axis of the air compressor 2, where it is compressed, and the compression to the end of the single pressure carried out continuously in a single stage of compression, and then compressed and thus heated air is divided into two streams, one of which is designed to produce nitric acid, direct cooling, for example, in “boiling” economizer 3 and then mixed with ammonia in the mixer 4, and the other is fed directly into the combustion chamber fuel 8 associated with recuperation turbine 9.

Thus the unit with a uniform pressure on the stages of the oxidation of ammonia and absorption of nitrogen oxides to nitric acid obtained by oxidation of ammonia with oxygen and absorption (absorption) of nitrogen oxides with water, works as follows. Atmospheric air passing through the filter 1, is fed to the suction of the air compressor 2, where the compression process. Compressed to the final uniform pressure of 0.7-1.0 MPa air, when heated is gatii to 280-360° With, is divided into two threads: the main thread that is designed to produce nitric acid enters the “boiling” economizer 3, which is cooled to 200-240°feed water with an initial temperature of 104°it is heated to the boiling temperature corresponding to the pressure of the steam generated in the HRSG 6, and boil the contents of the steam in the steam emulsion is discharged into parosbornoj 7 boiler 6 is not higher than 25%. The second stream (up to 15% of the total) without cooling flows into the combustion chamber 8, in which the tail gases are heated up to 500-750°due to the heat of combustion of natural gas and fed to the heat recovery turbine 9. The main stream of air after cooling is supplied to the mixer 4, which is heated in the heater 15 ammonia, ammonia-air mixture in the contact device 5, where the temperature 900-930°With ammonia is oxidized to nitrogen oxides. Nitrous gases are cooled in the exhaust-heat boiler 6 to 390-350°and act in the tail gas heater 10, which is heated to 260-280°and then the catalytic purification reactor 11; purified from nitrogen oxides in the tail gases are in recuperation turbine 9, the pre-heated in the combustion chamber fuel 8. Oxides of nitrogen, cooled to 150-180°come in the cooler-condenser 12 and then in the absorption column 13. Products : the traditional nitric acid rap from dissolved nitrogen oxides in the purge column 14, which is air cooled from 200-230°With up to 130-160°With the ammonia gas heater 15. To start the gas turbine installation is the starter 16.

1. Method for the production of nitric acid from ammonia by oxidation of ammonia with oxygen and absorption of nitrogen oxides with water in the unit with a single pressure stages of the oxidation of ammonia and absorption of nitrogen oxides using compressible in the production process of the air and products of combustion generated in the combustion chamber associated with recovery turbine, characterized in that the air is compressed to a single final pressure carried out continuously in a single stage of compression, and then compressed and thus heated air is divided into two streams, one of which is designed to produce nitric acid, direct the cooled and then mixed with ammonia, and the other is fed directly into the combustion chamber associated with recovery turbine.

2. A unit for the production of nitric acid from ammonia by oxidation of ammonia with oxygen and absorption of nitrogen oxides with water in the unit with a single pressure stages of the oxidation of ammonia and absorption of nitrogen oxides containing apparatus oxidation of ammonia by air, the absorption of nitrogen oxides, the gas turbine installation including a compressor for compressing air, the heat recovery turbine for expansion of the tail gas, the heated gases from the combustion chamber, fuel and air mixer of ammonia and its heater, the line of feed water for a boiler having parosbornoj, and the purge column nitric acid, characterized in that the gas turbine installation as a compressor for compressing air using axial compressor mounted directly on the same shaft with the recuperation turbine and the compressor outlet line of the compressed air stream is divided into two parts, one of which is designed to produce nitric acid, associated first with the cooler compressed air and then with mixer ammonia, and the second, designed for burning fuel directly to the combustion chamber of the regenerative turbine.

3. A unit for the production of nitric acid from ammonia according to claim 2, characterized in that as the cooler compressed air use "boiling" economizer connected to the line of feed water for boiler and paromomycin boiler line steam-water emulsion.

4. A unit for the production of nitric acid from ammonia according to claim 2, characterized in that the air line designed to produce nitric acid, is connected to the purge column nitric acid through the heater ammonia.