69 results about "Selective catalytic reduction" patented technology

This invention discloses a passive adsorption-selective catalytic reduction (CCR) device for diesel vehicles, comprising an electronically controlled nozzle, a first mixing chamber, a pre-catalytic oxidation-reduction chamber, a second mixing chamber, and a post-catalytic oxidation-reduction chamber arranged sequentially. The first mixing chamber includes a first urea solution inlet, a V-shaped breaker wall, and a W-shaped bottom mixing chamber. The V-shaped breaker wall is fixed to the rear wall of the first urea solution inlet pipe. The W-shaped bottom mixing chamber includes an inner cavity and an outer cavity. The inner cavity wall has staggered array openings, and the inner and outer cavities are connected through these openings. A guide wall structure is connected to the outermost pipe at the end of the first mixing chamber. The CCR chamber is connected to the end of the guide wall, and a three-zone integrated catalyst is located inside the CCR chamber. This invention solves the problems of severe NOx escape during the cold start phase, system complexity, and low-temperature urea crystallization in existing selective catalytic reduction technologies.

The invention relates to an exhaust gas treatment system comprising, in an upstream to downstream order, a first particulate filter, a device for injecting a nitrogenous reductant and a selective catalytic reduction (SCR) assembly, wherein the system further comprises a second particulate filter arranged downstream of the device for injecting a nitrogenous reductant.

Processes and apparatuses for treating NOx from a carbon dioxide stream. Prior to separating carbon dioxide and NOx, NOx is converted to nitrogen gas in an NOx conversion zone, which may include an SCR reactor and / or CO boiler. A carbon separation zone which may include one or more fractionation columns produces a CO2 stream and an NOx stream. The NOx is passed back to the NOx conversion zone.

A non-transitory computer-readable media having computer-readable instructions stored thereon that, when executed by at least one controller, cause the at least one controller to cause a first doser to cease dosing a first reductant portion of a reductant to a first exhaust portion of exhaust upstream of a first catalyst member disposed in a first leg of a selective catalytic reduction (SCR) system. The instructions can cause the at least one controller to cause a second doser to dose a second reductant portion of the reductant to a second exhaust portion of the exhaust upstream of a second catalyst member disposed in a second leg of the SCR system. The instructions can cause the at least one controller to determine a first conversion efficiency of the first leg while the first doser is not dosing the first reductant portion and the second doser is dosing the second reductant portion.

This application relates to the field of diesel engine exhaust gas treatment technology, and provides an aftertreatment system and a diesel engine. The aftertreatment system includes a first oxidation catalytic conversion module located downstream of the diesel engine's exhaust outlet; a particulate filter module located downstream of the first oxidation catalytic conversion module; a selective catalytic reduction module located downstream of the particulate filter module for reducing nitrogen oxides in the exhaust gas discharged from the particulate filter module; an ammonia oxidation catalytic module located downstream of the selective catalytic reduction module for oxidizing ammonia in the exhaust gas discharged from the selective catalytic reduction module; and a second oxidation catalytic conversion module located downstream of the ammonia oxidation catalytic module for decomposing nitrous oxide in the exhaust gas discharged from the ammonia oxidation catalytic module. Using this system can significantly improve exhaust gas treatment efficiency.

The application provides a remote data processing method for identifying and analyzing extreme scenarios of an assisted vehicle, including: obtaining vehicle remote data; identifying abnormal data in the remote data and nullifying the identified abnormal data to form to-be-supplemented correction data, and dividing the to-be-supplemented correction data into transient parameters and slowly changing parameters; correcting a first nullification position of the corresponding transient parameters and a second nullification position of the slowly changing parameters in the to-be-supplemented correction data to obtain corrected data; inputting vehicle speed, acceleration, engine torque, and altitude in the corrected data into a load prediction model to output vehicle load; calculating engine emission flow according to engine intake volume and fuel consumption in the corrected data; inputting temperature corresponding to the selective catalytic reduction system inlet, engine emission flow, and atmospheric pressure in the corrected data into a nitrogen oxide conversion efficiency lower limit prediction model to output the nitrogen oxide conversion efficiency lower limit. The method effectively improves the quality of remote data through a parameter classification and differentiated correction mechanism, thereby solving the problem of low accuracy in determining extreme scenarios.

The present invention provides a selective catalytic reduction (SCR) catalyst, for treating a gas mixture comprising NOx, the SCR catalyst comprising 50 to 90 wt% of a metal loaded zeolite and > 5 to 35 wt% of a binder in the form of titanium dioxide or silica- stabilised titanium dioxide.

A method for exhaust aftertreatment of an internal combustion engine (10) with an exhaust system (20) in which a NOx storage catalyst (28) with a low-temperature storage component (48) made of cerium oxide and a high-temperature storage component (52) made of barium carbonate as well as an SCR catalyst (34) and / or particulate filter (30) with an SCR coating (32) arranged downstream of the NOx storage catalyst (28) in the flow direction of an exhaust gas of the internal combustion engine (10), comprising the following steps: - Modeling the loading state of the NOx storage catalyst (28), wherein - the charging of the low-temperature storage component (48) is determined by a first model for the charging of the low-temperature storage component (48), and - the loading of the high-temperature storage component (52) is determined by a second model for the loading of the high-temperature storage component (52), - Regenerating the NOx storage catalyst (28) by introducing unburned hydrocarbons into the exhaust system (20) of the combustion engine (10) when the high-temperature storage component (48) has reached a defined loading level and the SCR catalyst (34) or the particulate filter (30) with the SCR coating (32) has an operating temperature at which selective catalytic reduction of nitrogen oxides is possible, wherein - depending on whether the SCR catalyst (34) or the particulate filter (30) with the SCR coating (32) has an operating temperature at which selective catalytic reduction of nitrogen oxides is possible, at least two threshold values ​​are used, wherein - a first threshold value is provided at which a regeneration of the NOx storage catalyst (28) is carried out when the SCR catalyst (34) or the particulate filter (30) with the SCR coating (32) has reached its operating temperature and wherein - a second threshold is provided at which regeneration of the NOx storage catalyst (28) takes place independently of the temperature of the SCR catalyst (34) or the particulate filter (30) with SCR coating (32).

The present invention provides an all-active, extruded selective catalytic reduction (SCR) catalyst, comprising a metal-loaded zeolite and a binder in the form of silica-alumina, wherein the silica content of the silica-alumina is in the range of about 1% to 20% by weight. The invention further provides a method of preparing such an SCR catalyst comprising (a) forming a plastic mixture having a solids content of greater than 50 % by weight by mixing together a metal-loaded zeolite or a zeolite in an H+ or NH4+ form and an active metal precursor; an inorganic matrix component comprising silica-containing boehmite, wherein the silica content of the silica-boehmite is in the range about 1% to 20% by weight; an organic auxiliary agent, an aqueous solvent and optionally inorganic fibres; (b) moulding the plastic mixture into a shaped article; and (c) calcining the shaped article to form a solid catalyst body.

The embodiment of the present application relates to the technical field of SCR catalyst regeneration, and provides an SCR catalyst module individualized regeneration system and method, the system comprises: a pre-regeneration detection unit for detecting the key characteristics of each SCR catalyst module to be regenerated respectively, and obtaining the corresponding key detection data; an intelligent control unit for formulating the individualized regeneration scheme corresponding to each SCR catalyst module according to the key detection data; and a regeneration execution unit for calling and executing the individualized regeneration scheme corresponding to the SCR catalyst module entering the regeneration station, and completing the individualized regeneration of the SCR catalyst module in the regeneration station. The embodiment of the present application can realize the accurate regeneration of each SCR catalyst module in the same batch, improve the regeneration quality, and has economic efficiency as a whole.

This invention discloses an intelligent collaborative control system and method for mesophilic selective catalytic reduction (SCR) denitrification. The system includes a multi-dimensional full-process sensing module, a full-process operating condition prediction module, a multi-objective collaborative optimization module, a collaborative control execution module, and an execution layer module, forming a closed-loop control link for the entire process. The collaborative control execution module includes a parallel-connected flue gas temperature control module and a precise ammonia injection collaborative control module. This invention constructs a dual-channel parallel feedforward architecture, enabling flue gas temperature regulation and ammonia injection regulation to cooperate in time sequence, achieving advanced collaborative control. The flue gas temperature control module incorporates a gas consumption prediction model to achieve uninterrupted heat supply switching. The ammonia injection control module introduces a long-term and short-term self-learning mechanism, integrating minute-level mutation data and daily-level trend data to generate precise feedforward values. The multi-objective collaborative optimization module uses a particle swarm optimization algorithm to solve for the optimal combination of operating parameters. This invention effectively solves the problems of control lag, excessive ammonia escape, and high heat supply energy consumption in mesophilic SCR denitrification.

Method for controlling an internal combustion engine (10) with at least one combustion chamber (12), wherein the internal combustion engine (10) is connected on the intake side to an air supply system (20) and on the exhaust side to an exhaust system (40), wherein the exhaust system (40) is connected to the air supply system (20) via a high-pressure exhaust gas recirculation (90) and a low-pressure exhaust gas recirculation (80), comprising the following steps: - determining an ambient temperature, - determining a temperature of an exhaust aftertreatment component (50, 52) for the selective catalytic reduction of nitrogen oxides, - determining a power demand and / or a torque demand on the internal combustion engine, - determining a NOx concentration in the exhaust system (40), - temporarily enabling the low-pressure exhaust gas recirculation (80) when • the ambient temperature is below a first threshold temperature (TUS),• the power requirement and / or the torque requirement to the internal combustion engine (10) exceeds a threshold value (hp, mp), and • the conversion capability of the exhaust aftertreatment component (50, 52) for selective catalytic reduction of nitrogen oxides is below a second threshold (KNAS) or the temperature of the exhaust aftertreatment components (50, 52) for selective catalytic reduction of nitrogen oxides is below a second threshold temperature (TNAS).

A catalyst composition, which comprises a support, and catalytically active components supported on the support, including a vanadium component, an antimony component and a cerium component, wherein the cerium component is present in an amount in the range of from 0.1% to 5% by weight, preferably from 0.4% to 4 % by weight, calculated as CeO 2, based on the total weight of the catalyst composition, and wherein the cerium component and the vanadium component are present in a Ce / V molar ratio in the range of from 0.01 : 1 to 0.8 : 1, preferably from 0.05 : 1 to 0.6 : 1. It also relates to a catalytic article comprising the catalyst composition, and a method for treating an exhaust stream.

The present invention relates to a process for the preparation of a catalyst composition comprising - a support comprising TiO2, - a composite oxide comprising vanadium and antimony, having a rutile structure different from VSbO4 and V 0.92 Sb 0.92 O4 as determined by X-ray diffraction (XRD) analysis using Cu Ka radiation and - optionally, one or more selected from silicon oxide, vanadium oxide and antimony oxide; said process comprising the steps of: (i) mixing vanadium / antimony oxide and optional silicon source with the support comprising TiO2 in a solvent to obtain a suspension; (ii) optionally, applying the suspension onto a substrate; (iii) drying at a temperature in the range of 80 to 250 °C; (iv) calcination at a temperature of 600 °C to 700 °C.

A fire fighting vehicle includes a chassis, an engine configured to produce exhaust gas, and an exhaust aftertreatment system including a first housing including a first housing inlet fluidly coupled with the engine and configured to receive the exhaust gas, a diesel oxidation catalyst (DOC) disposed within the first housing, the DOC positioned to receive the exhaust gas from the first housing inlet, a diesel particulate filter (DPF) disposed within the first housing, the DPF positioned to receive the exhaust gas from the DOC, a second housing including a second housing inlet configured to receive the exhaust gas from the first housing, a selective catalytic reduction catalyst (SCR) disposed within the second housing, the SCR positioned to receive the exhaust gas from the second housing inlet, and a thermal management system including a heater coupled with at least one of the first housing or the second housing.

The application discloses a selective catalytic reduction flue gas heating device, which comprises a flue gas transmission main line and a combustion furnace chamber, the output end of the combustion furnace chamber is inserted into the flue gas transmission main line, a furnace chamber collector and a burner are arranged in the combustion furnace chamber, a control valve is arranged at the input end of the flue gas transmission main line, a main line collector is arranged in the flue gas transmission main line, and the heating device further comprises a collection system, a data analysis system, a control module and a heater. The selective catalytic reduction injection pipe is directly connected to the obliquely-inserted combustion furnace chamber, is used for direct combustion of the burner, the high-temperature flue gas generated by combustion is mixed with the flue gas of the main line of the internal combustion engine to improve the flue gas temperature of the internal combustion engine, the prepared flue gas heating device is compact in structure, convenient to arrange, simple in preparation process, low in cost, convenient to maintain, can adjust the power of the burner according to different exhaust pipe diameters, and is high in thermal efficiency and economic benefits.

This disclosure provides catalyst compositions that may be useful in general for selective catalytic reduction. The catalyst compositions may include a zeolite containing copper and at least one additional metal. The catalyst compositions described herein may be used for NO in a gaseous stream. x Methods for reducing the amount of exhaust gas and exhaust gas treatment systems are also described.

This invention belongs to the field of flue gas treatment technology and provides a process for desulfurization, denitrification, and dust removal of flue gas from waste incineration power plants. The process includes the following steps: Step 1: The flue gas from the waste incineration boiler outlet is introduced into a circulating fluidized bed reactor for desulfurization treatment. After the desulfurization reaction, the gas-solid mixture is separated by a gas-solid separator to obtain desulfurized flue gas; Step 2: The temperature of the desulfurized flue gas is adjusted using a burner, and then introduced into an integrated dust and nitrogen removal device with ceramic fiber catalytic filter tubes inside. While filtering dust, a selective catalytic reduction denitrification reaction occurs on the surface and inside of the filter tubes to obtain denitrified and dust-removed flue gas; Step 3: The denitrified and dust-removed flue gas is discharged externally by an induced draft fan. This invention simplifies the desulfurization, denitrification, and dust removal process, reduces the number of equipment and floor space required, lowers system investment and operation and maintenance costs, and simultaneously meets the stringent requirements for waste incineration flue gas emissions.

The application belongs to the technical field of waste gas treatment equipment, and particularly relates to a catalysis and denitrogenation integrated purification system and method for post-tail gas of rotary RTO, which comprises a pretreatment unit, a catalytic oxidation unit, a temperature adjusting device and a selective catalytic reduction unit connected in sequence along the flow direction of waste gas, the catalytic oxidation unit is filled with a supported noble metal catalyst, a urea solution spraying device is arranged on the gas inlet pipeline of the selective catalytic reduction unit, and the selective catalytic reduction unit is filled with an SCR catalyst, ammonia gas generated by pyrolysis of urea solution sprayed by the urea solution spraying device is mixed with the gas adjusted in temperature by the temperature adjusting device, and then selective catalytic reduction reaction occurs under the action of the SCR catalyst, so that nitrogen oxides in tail gas are converted into nitrogen and water. The application solves the core pain points in the existing rotary RTO tail gas treatment technology, such as system dispersion, temperature control mismatch, catalyst deactivation, high risk of reducing agent, high energy consumption and the like.

According to the present invention there is provided a method for producing a catalyst for the selective catalytic reduction of NOX in a gas mixture. The method comprises the steps of: (a) preparing a slurry comprising vanadium (V), antimony (Sb) and a reactive media to form a colloidal sol of VSbO4; (b) combining the colloidal sol of VSbO4 with a catalyst support material, which comprises depositing the colloidal sol of VSbO4 on the catalyst support material, to form a mixture; and (c) optionally drying and calcining the resulting mixture. The invention also relates to catalyst produced by the method, associated uses thereof.

The present invention relates to a method for preparing a catalyst for the selective catalytic reduction of nitrogen oxides, the method comprising, among other steps, preparing a second aqueous mixture comprising water and an iron salt, and disposing the second aqueous mixture on the substrate obtained according to step (ii) over y% (y in the range of 10 to x) of the axial length of the substrate from the inlet end to the outlet end of the substrate to obtain a coating comprising a zeolite material containing copper and an iron salt over y% of the axial length of the substrate in a first zone; and, if x>y, obtaining a substrate comprising a coating comprising a zeolite material containing copper in a second zone extending from y% to x% of the axial length of the substrate from the inlet end to the outlet end.

This invention provides an engine aftertreatment system, a control method, an engine, electronic equipment, and a vehicle. The aftertreatment system is configured with a redox-type exhaust aftertreatment system installed in the engine's main exhaust pipe. A nitric oxide selective oxidation chamber is provided in the bypass exhaust path. Exhaust gas generated by the hydrogen engine enters the nitric oxide selective oxidation chamber through the bypass exhaust path. The nitric oxide selective oxidation chamber converts nitric oxide in the exhaust gas into nitrogen dioxide and outputs the converted exhaust gas. The nitric oxide selective oxidation chamber is connected to the engine's main exhaust pipe via a reflux device. The converted exhaust gas is returned to the redox-type exhaust aftertreatment system through the reflux device and the engine's main exhaust pipe. This allows for the active creation of a suitable NO2 / NOx ratio on the aftertreatment system side without changing the engine's combustion parameters, thereby effectively improving the efficiency of the selective catalytic reduction reaction.

The present invention provides a selective catalytic conversion correction method and system, belonging to the field of vehicle energy conservation and emission reduction calculation. The method includes: obtaining the correction amount of the nitrogen oxide sensor according to the HC injection flow rate and the oxygen concentration at the engine outlet, taking the sum of the measured value and the correction amount as the true measured value of this nitrogen oxide sensor, taking the product of the true measured value, the exhaust gas flow rate and the conversion coefficient as the theoretical NH3 injection amount, determining the open-loop set conversion efficiency according to the space velocity and temperature of the selective catalytic conversion device, and taking the product of the open-loop set conversion efficiency, the efficiency correction coefficient based on the temperature of the selective catalytic conversion device, the correction coefficient based on the HC injection amount and the theoretical NH3 injection amount as the final NH3 injection amount; the present invention corrects the NOx sensor by the input HC amount to obtain the correct input NOx concentration, and then corrects the current set efficiency by the HC amount, ensuring the accuracy of NOx control.

The present application relates to a kind of reductant and method for inhibiting ammonia escape in SCR denitration system, the method uses the mixed reductant comprising ammonia and / or organic amine, in the presence of catalyst to the flue gas containing nitrogen oxide (NO x ) Selective catalytic reduction is carried out denitration treatment;Wherein, the organic amine has self-destruction characteristics on catalyst surface, can effectively inhibit the escape of unreacted ammonia when NO x Concentration fluctuation leads to reductant excess injection.The present application provides a kind of method for inhibiting ammonia escape in SCR denitration system, in the method, utilize the self-destruction characteristics of organic amine on catalyst surface, when NO x Concentration fluctuation in flue gas leads to reductant transient excess, organic amine is preferentially decomposed into harmless small molecules such as N2, CO2, H2O, etc., dynamically consumes excess reductant equivalent, effectively blocks the escape path of unreacted ammonia.Practical measurement shows that, under the condition of load severe fluctuation, ammonia escape concentration can be stably controlled below 3 ppm, greatly reduces the risk of secondary pollution.

This invention proposes a coaxial sleeve-type integrated ammonia cracking and selective catalytic reduction reaction device, comprising: an exhaust pipe, a reaction sleeve, an ammonia inlet pipe, and a heat exchange sleeve. The exhaust pipe is filled with an SCR catalyst. The reaction sleeve is coaxially sleeved outside the exhaust pipe, with a first annular gap between the reaction sleeve and the exhaust pipe, and the first annular gap is filled with the ammonia cracking catalyst. The ammonia inlet pipe is connected to the inlet of the reaction sleeve. The heat exchange sleeve is coaxially sleeved outside the ammonia inlet pipe, with a second annular gap between the heat exchange sleeve and the ammonia inlet pipe, and the inlet of the heat exchange sleeve is connected to the exhaust port of the reaction sleeve. This invention can fully utilize the waste heat of the internal combustion engine exhaust gas, and through the heat conduction effect of the inner and outer pipe walls, transfer the heat of the exhaust gas in the inner pipe to the ammonia cracking reaction channel in the outer pipe, reducing the energy consumption of ammonia cracking, significantly improving the system integration, and reducing the complexity of the system layout.

A work vehicle includes an exhaust gas purification device that purifies exhaust gas discharged from an engine, and a fulcrum on an upper side of the exhaust gas purification device defining a rotation fulcrum of a hood. The exhaust gas purification device includes a DPF case to collect particulate matter in exhaust gas discharged from the engine, and an SCR case to purify nitrogen oxides in the exhaust gas. The DPF case and the SCR case are positioned such that a longitudinal direction of the DPF case and the SCR case faces a front-rear direction, and are side by side in a left-right direction.

The nitrogen oxide emission reduction system according to an exemplary embodiment of the present invention provides a system that links selective catalytic reduction (SCR) and selective non-catalytic reduction (SNCR) methods. This effectively removes nitrogen oxides and nitrous oxide contained in exhaust gases generated from ammonia combustion. In particular, by optimizing the content of nitrogen oxides and reducing agents, the removal efficiency of nitrogen oxides and nitrous oxide can be further improved.

The application discloses a composite catalyst for synergistically removing CO and NO x , a preparation method and application thereof, and relates to the technical field of industrial catalysis. The catalyst is obtained by calcining a composite component CuCeM1O x and a molecular sieve component CuM2-SSZ-13 after mechanical ball milling. The CuCeM1O x is prepared by a mechanical ball milling method, and the CuM2-SSZ-13 is prepared by a hydrothermal synthesis method. After the two components are compounded, multi-component micro-uniform mixing and structural synergy are realized. By adjusting the component ratio and process parameters of the two components, the synergistic removal performance of the catalyst in the coupling reaction of CO oxidation and NH3 selective catalytic reduction is significantly improved. The catalyst is suitable for purifying industrial waste gas containing CO and NO x of a steel sintering tail gas and a non-electricity industry, has a simple preparation process, is easy to produce on a large scale, and has a wide application prospect.