System and method for protection of scr-catalyst and regulation of multiple emissions

FIELD: chemistry.

SUBSTANCE: invention relates to method for increasing active service term of SCR-catalyst. Method includes introduction of at least one kaolin-bearing compound into combustion zone or into furnace or boiler flue gas stream before flue gas gets into SCR-system, and realisation of spontaneous reaction of at least one kaolin-bearing compound with any gaseous compounds of potassium, and/or sodium, or potassium- and/or sodium-containing compounds, present in combustion zone or in flue gas, before flue gas gets into SCR-system. Method makes it possible to reduce poisoning and pollution of SCR-catalyst.

EFFECT: invention relates to method for increasing active service term of SCR-catalyst with simultaneous regulation of mercury in gas.

18 cl, 1 dwg

 



 

Same patents:

FIELD: chemistry.

SUBSTANCE: invention relates to a trap-type catalyst for cleaning NOx-depleted exhaust gases, containing catalytic noble metals: platinum, palladium and rhodium; inorganic oxides which support the catalytic noble metals; and at least one NOx adsorbent selected from a group consisting of magnesium, barium, sodium, potassium and caesium; wherein among said inorganic oxides, the inorganic oxide supporting palladium, contains cerium, aluminium and/or zirconium, and wherein said inorganic oxide contains 1-20 wt % cerium in terms of CeO2.The invention also relates to an exhaust gas cleaning system, containing said catalyst and an additional catalytic converter which contains a catalytic noble metal and is placed upstream of the trap-type converter for cleaning NOx-depleted exhaust gases relative to the direction flow of exhaust gases.

EFFECT: longevity of the catalyst and exhaust gas cleaning system.

5 cl, 3 tbl, 1 dwg, 17 ex

FIELD: chemistry.

SUBSTANCE: invention relates to a catalyst composition for selective catalytic reduction of exhaust gas. The catalyst composition contains a vanadate of formula XVO4/S, where XVO4 denotes a vanadate of Bi, Sb, Ga and/or Al, optionally in a mixture with one or more vanadates of rare-earth metals, or in a mixture with one or more vanadates of transition metals, or in a mixture with one or more vanadates of transition metals and one or more vanadates of rare-earth metals, and S is a support which includes TiO2. A method of producing the catalyst composition is also disclosed.

EFFECT: improved heat resistance and improved NOx conversion activity of the supported catalyst composition.

13 cl, 1 dwg, 8 tbl, 7 ex

Nox trap // 2554576

FIELD: chemistry.

SUBSTANCE: invention relates to a NOx trap, i.e. NOx adsorber catalyst, which is a part of exhaust gas aftertreatment systems for internal combustion engines. The catalyst comprises a honeycombed substrate monolith. The first layer substrate comprises components comprising at least one platinum group metal, at least one NOx storage material and bulk ceria or a bulk cerium-containing mixed oxide deposited uniformly in a first layer and a dispersion of rare earth oxides. The first layer has a first, upstream, zone and a second, downstream zone. The loading of the dispersion of rare earth oxide in the first, upstream, zone, g/l, is in the range 0-30% of the loading of the dispersion of the rare earth oxide in the second, downstream, zone. The first, upstream, zone has increased activity relative to a second, downstream zone for oxidising hydrocarbons and carbon monoxide. And a second, downstream, zone has increased activity to generate heat during a desulphation event, relative to the first, upstream, zone.

EFFECT: improved NOx reduction at lower temperatures, offering the ability to release trapped sulphur more efficiently and/or with a less demanding desulphation event.

14 cl, 2 dwg, 1 tbl, 3 ex

FIELD: chemistry.

SUBSTANCE: invention relates to the field of selective catalytic reduction of nitrogen oxides, namely to a material of a carrier for the catalyst, used in the said process. The claimed carrier material represents particles of anatase titanium dioxide, including ≥85% by dry weight of TiO2 and ≤10% by dry weight of SiO2, with (i) SiO2 being mainly in the form, selected from the group, consisting of forms with the low molecular weight, nanoparticles and their combinations; and (ii) at least 50% of silicon atoms being in states Q3, Q2, Q1 and Q0 of the coordination environment. The invention also relates to a catalytic device for the neutralisation of Diesel exhaust, including such particles, a system for Diesel exhaust regulation, including the said catalytic device, a method in which the conversion of nitrogen oxides is catalysed in the presence of the claimed particles of anatase titanium dioxide, as well as to methods of obtaining the said particles.

EFFECT: claimed particles make it possible to increase the thermal stability of the final catalyst with the preservation or increase of the catalytic activity for the selective catalytic reduction of nitrogen oxides from mobile devices, operating on lean mixtures.

44 cl, 18 dwg, 15 tbl, 18 ex

FIELD: engines and pumps.

SUBSTANCE: invention relates to a manufacturing method of a honeycomb ceramic unit for a catalytic neutraliser of exhaust gases, according to which to the ceramic unit from the main material there applied is a binding layer containing sodium silicate Na2O(SiO2)n or potassium silicate K2O(SiO2)n, or their mixture, above which there formed is at least one substrate layer for application of a catalyst, which contains a nanodispersed oxide of aluminium hydroxide (boehmite); for that purpose, a suspension layer is applied onto the second workpiece, which contains nanodispersed oxide of aluminium hydroxide; the workpiece with the applied suspension layer is dried; after that, the workpiece of the honeycomb ceramic unit with the applied substrate material is roasted, and therefore, a honeycomb ceramic unit for a catalytic neutraliser of exhaust gases is obtained. In addition, an application method of substrate onto the honeycomb ceramic unit for the catalytic neutraliser of exhaust gases, which applies this technology, is proposed.

EFFECT: improvement of passage of a gas flow through pores and channels of a substrate; increase and optimisation of a catalytic neutralisation process of substances in exhaust gases of diesel engines.

17 cl, 24 dwg, 1 ex

FIELD: engines and pumps.

SUBSTANCE: invention relates to control over amount of reducing agent fed to ICE exhaust line. Proposed device adjusts the amount of univalent nitrogen fed to exhaust line (3) of ICE (1) comprises system (8-12) to feed reducing agent to exhaust line (3), first catalyst (13) to reduce the amount of nitrogen oxides in exhaust gases in said line (3) by feed of reducing agent. Second catalyst (14) is arranged downstream said first catalyst (13) in said line (3) to convert exhaust gas ammonia into gaseous nitrogen and univalent nitrogen oxide. This device comprises univalent nitrogen oxide sensor (17) to track the amount of said oxide in said line (3) at the point located downstream of second catalyst (14). Control unit (10) executes control over system (8-12) for adjustment of the amount (q) of reducing agent fed to exhaust line (3). Adjustment is executed in response to the signal of sensor (17) generated if univalent nitrogen oxide amount fall beyond preset range (A). Invention covers also the process of control over reducing agent feed to exhaust line (3) of ICE (1) depending on the amount of univalent nitrogen oxide.

EFFECT: optimum decrease in emission of nitrogen oxides.

22 cl, 2 dwg

FIELD: chemistry.

SUBSTANCE: invention relates to catalytic purification of exhaust gases of internal combustion engines. Claimed is composition for purification of exhaust gases of internal combustion engines based on cerium oxide, containing niobium oxide, with the following weight contents: niobium oxide from 2 to 20%, the remaining part - cerium oxide. Also claimed is composition with the following weight contents: cerium oxide at least 65%, niobium oxide from 2 to 12%, zirconium oxide to 48%. After calcinations for 4 hours at 800°C compositions have acidity at least 6·10-2, with said acidity being expressed in ml of ammonia per m2 of composition, with the surface, expressed in m2, used for determination of acidity, representing specific surface after calcinations for 4 hours at 800°C and specific surface at least 15 m2/g, and after calcinations for 4 hours at 1000°C it has specific surface at least 2 m2/g, in particular at least 3 m2/g. Invention relates to catalyst, which contains said compositions, to methods of oxidising CO and hydrocarbons, N2O, decomposition, for HOx and CO2 adsorption. Said compositions and catalyst are applied in reaction of gas with water, reaction of conversion with water steam, isomeration reaction, reaction of catalytic cracking and as triple action catalyst.

EFFECT: compositions possess satisfactory reducing ability in combination with good acidity, specific surface of which remains suitable for application in catalysis.

16 cl, 1 tbl, 14 ex

FIELD: process engineering.

SUBSTANCE: invention relates to welding of metal cellular element (1) used for decreasing the toxicity of used gases. This process comprises the steps that follow: a) cellular element (1) is subjected to preliminary treatment at 400°C; b) cellular element (1) is cooled; c) cellular element (1) is subjected to welding at 1050-1100°C at barometric pressure; d) cellular element (1) is cooled. Proposed device comprises first furnace (4) to implement step a), second furnace (5) for step c) and conveyance system (6). Saud system (6) extends through both furnace (4, 5) and incorporates cooling section with temperature regulator to maintain the temperature of step b), intermittent-action drive (7) and gates (8) to isolate first furnace (4) with formation of working area (9).

EFFECT: lower toxicity of off-gases.

10 cl, 5 dwg

FIELD: chemistry.

SUBSTANCE: catalyst contains a substrate, a catalytic rhodium-containing layer and a catalytic platinum-containing layer. Described is a relationship between molar-average Pauling electronegativity X, which is calculated with respect to elements contained in the rhodium-containing catalytic layer, except platinum-group elements and oxygen, and the molar-average Pauling electronegativity Y, calculated with respect to elements contained in the platinum-containing catalytic layer, except platinum-group elements and oxygen. The following inequalities hold: 1.30≤X≤1.45 and 1.47≤Y≤2.0.

EFFECT: obtaining a catalyst for limiting spent gas emission with high efficiency of cleaning spent gases.

10 cl, 4 dwg, 3 tbl, 7 ex

FIELD: chemistry.

SUBSTANCE: invention relates to composition for purification of exhaust gases based on cerium, zirconium and tungsten. Claimed composition has the following weight contents, expressed in oxide: cerium oxide - from 5 to 30%, tungsten oxide - from 2 to 17%, the remaining part - zirconium oxide. After ageing at 750°C in air atmosphere with 10% of water it has two-phase crystallographic structure, containing tetragonal phase of zirconium oxide and monoclinic phase of zirconium oxide, without presence of crystalline tungsten-containing phase. Claimed invention also relates to method of obtaining such composition, catalytic system, containing said composition, as well as to methods of processing gas for conversion of nitrogen oxides and catalytic oxidation of carbon monoxide with application of said composition.

EFFECT: claimed composition makes it possible to effectively purify exhaust gases from nitrogen oxides and carbon monoxides.

13 cl, 2 dwg, 2 tbl, 4 ex

FIELD: process engineering.

SUBSTANCE: invention relates to hydrocarbon gas cleaning. Proposed method comprises removal of mercaptans by their oxidation to sulfur and disulfides in the presence of catalyst at increased temperature and condensation of liquid products of oxidation. Note here that gas is mixed with oxidation products to separate liquid oxidation products and separation gas therefrom. Separation gas is subjected to adsorption cleaning at adsorbent cooling to adsorption temperature but not lower than that of water freezing or hydration. Adsorbent regeneration is performed by blowing with cleaned gas at lower pressure and heating of adsorbent by heat carrier to regeneration temperature while regenerated adsorbent is cooled by coolant to adsorption temperature. Note also that regeneration gas is mixed with air at weight ratio of mercaptans to air oxygen of 2.2-3.1 to force obtained mix through oxidation catalyst at weight hour space velocity and oxidation temperature while oxidation products are forced into flow of gas being cleaned by pump by compressing it to hydrocarbon gas pressure using liquid products of oxidation as the working fluid.

EFFECT: efficient cleaning, low input of materials and power.

2 cl, 1 dwg, 1 ex

FIELD: power engineering.

SUBSTANCE: energy-saving device for cleaning of smoke gases of a group of heat generators of apartment heating systems comprises a box laid onto the upper slab of the building, made from a corrosion-resistant material, the bottom of which is equipped with holes connected with pipes of individual flues and sewage drains and connected on the opposite edges with atmosphere via flues with deflectors, besides, each flue at the rear side is equipped with a door, inside it there are rows of vertical perforated cassettes opened on top, forming vertical gas channels between each other, vertical perforated cassettes are made from a corrosion-resistant material, their cavities are filled with an adsorbent - granules of pumice made from metallurgical slags with lime factor M>1 and diameter of granules from 5 to 10 mm, the bottom of the box is made with inclination I towards sewage risers, and upper edges of pipes of individual flues are arranged above the level of the bottom of the box by the value of δ.

EFFECT: higher reliability and efficiency of an energy-saving device for cleaning of smoke gases of a group of heat generators of apartment heating systems.

5 dwg

Gas cleaning // 2477643

FIELD: process engineering.

SUBSTANCE: this invention relates to cleaning of flue gas containing solid particles entrapped by said gas. This invention relates to cleaning of flue gas containing solid particles entrapped by said gas including: heating gas bearing solid particles for their sublimation if they are not sublimated; bringing said gas in direct contact with appropriate solid reagent selected from slaked lime, quick line or commercially available limestone to remove sublimated ammonium chloride therefrom and to remove cleaned gas from the system.

EFFECT: efficient cleaning.

7 cl, 4 dwg

FIELD: process engineering.

SUBSTANCE: invention relates to sorption appliances and serves to clean air of chemically harmful substances. Absorbing filter comprises case with bottom, detachable cover with bolt-on flange joint, inlet and outlet branch pipes, axial stud with press nut, coaxial filtration element and formed sorption unit. Sorption unit consists of hollow cylinder made up of carbon-containing sorbent and thermoplastic polymer. Inlet branch pipe is rigidly jointed to cover bottom. Additionally, filter incorporates inlet branch pipe attached to case bottom and T-joints connected to inlet branch pipes and stud for tight pressure of filtration element and sorption unit to case cover and bottom. Carbon-containing sorbent is impregnated with compounds of copper, chromium, silver and triethylene amine while sorption unit incorporates chemical absorber impregnated with nickel sulphate solution.

EFFECT: higher dynamic activity, reliable seal of filtration element and sorption unit.

1 dwg

FIELD: purification systems.

SUBSTANCE: invention relates to the supporting means of chemical processes and designated for the removal of the solid matters/gas mixture from the high pressure reservoir with fluidized layer; the stated bellow effect is attained due to that the outlet system comprises the sediment tank having the conic top head, the outlet line connecting by means of the fluid medium the high-pressure reservoir with the fluidized layer to the sediment tank, the primary eduction valve regulating the flow of the fluid mixture from the high-pressure reservoir with the fluidized layer through the outlet line to the sediment tank, the by-pass tank connected by means of the fluid medium to the sediment tank, the by-pass valve installed between the sediment tank and the by-pass tank regulating the by-pass flow from the sediment tank to the by-pass tank and the primary eduction valve regulating the outgoing flow of the fluid mixture from the by-pass tank.

EFFECT: enhanced substance processing efficiency with the simultaneous safety improvement due to securing the minimal removal of gas during the solid matter removal upon the maximum fill-up of the whole volume of the sediment reservoir.

33 cl, 5 dwg

FIELD: process engineering.

SUBSTANCE: invention may be used in heat engineering. Proposed column comprises casing 1 representing rectangular box 2 with detachable front wall 3 with its top accommodating air discharge slits, and rear wall 5 with intake air slits. Said rectangular box 2 is closed from below by flat-pyramid bottom 7 with detachable cup and, from above, by prismatic cover 9 that houses damper 10 provided with inlet 11 and outlet 12 branch pipes communicated with heat generator gas duct. Casing 1 is divided by vertical baffle 13 to form opening 14 nearby bottom and to divide casing 1 into first section I accommodating first treatment stage and second section II accommodating second and third treatment stages. First, second and third treatment stages consist of vertical perforated cartridges 15, 17 and 18, respectively. First treatment stage cartridges are filled with particles of crushed lime hydrate (Ca(OH)2), second treatment stage cartridges are filled with active carbon particles, while third treatment stage is filled with metal screen coated by paraffin layer.

EFFECT: partial leaning of flue gas of nitrogen oxides, carbon oxides, carbon dioxide, organic impurities and solid suspensions.

7 dwg

FIELD: process engineering.

SUBSTANCE: invention can be used in chemical and petrochemical industries. Air fed into apparatus of reclamation of zeolite or nonzeolite molecular sieve catalyst is cleaned of metal salts. First, initial air is cooled to remove air in condenser and, then rinsed in scrubber to remove, is fact, all salts from said initial air. Preferably, water removed at cooling stage is recirculated to remove salts from initial air.

EFFECT: longer life.

10 cl, 1 ex

FIELD: mechanics; air conditioning systems.

SUBSTANCE: invention relates to the method and the device for air conditioning indoors by means of an air mixture with a reduced oxygen partial pressure compared to that of ambient air. The invention aims for developing a method of air conditioning indoors including a necessary air regeneration, particularly in premises intended for people, which would allow creating the conditions of norm barometric hypoxia in the most cost effective way. The problem of air conditioning in a single premise (38) is solved by using an air mix with a reduced partial pressure compared to that of ambient air. Here, note, one part of oxygen (O2) contained in ambient air is reduced to a reaction product in exchange reaction with a combustible substance. The air mix thus processed is fed as a plenum air into the above single premise (38) to be air conditioned. The method is implemented by using device (10) intended for air conditioning in single premise (38) by means of an air mix with a reduced partial pressure compared to that of ambient air including O2, a reducing agent (16) to reduce one part of (O2), contained in ambient air in exchange reaction with a combustible substance to form a reaction product. There is also a feeding device (37) to force thus processed air mix into single premise (38) to be conditioned.

EFFECT: availability of the device for air conditioning the premises to work in the conditions of reduced partial pressure of oxygen.

25 cl, 4 dwg

FIELD: organic chemistry, chemical technology.

SUBSTANCE: invention relates to a method for preparing poly(vinyl chloride). Method involves preparing an aqueous emulsion of poly(vinyl chloride) using (C10-C18)-saturated acid salt, drying the prepared emulsion in heated air, isolation spent gases after drying with unfavorable odor in atmosphere. Method involves a stage for diminishing unfavorable odor in spent gases wherein this odor is caused by the presence of (C10-C18)-saturated acid by spraying and spent air of an aqueous solution containing at least stoichiometric amount of a base that interacts with indicated (C10-C18)-saturated acid to form salt. In specific example of the invention realization unfavorable odor is caused by the presence of lauric acid. Invention provides elimination of unfavorable odor evolving in manufacturing polyvinyl chloride.

EFFECT: improved preparing method.

18 cl, 3 ex

The invention relates to a method of removing gaseous oxidizable components of the gas phase and is used preferably for the removal of ethylene during fruit storage, removal of mercury (vapor) from natural gas and removal of H2S at concentrations of 0.001-10 mg/m3
The invention relates to environmental protection and waste-free technologies and can be applied in all sectors of economic activity
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