82results about How to "Reduce nitrogen oxides" patented technology

An exhaust gas aftertreatment installment and associated exchaust gas aftertreatment method utilizes a nitrogen oxide storage catalytic converter and an SCR catalytic converter. A particulate filter is provided upstream of the nitrogen oxide storage catalytic converter or between the latter and the SCR catalytic converter or downstream of the SCR catalytic converter. The time of regeneration operating phases of the nitrogen oxide storage catalytic converter can be determined as a function of the nitrogen oxide content of the exhaust gas downstream of the nitrogen oxide storage catalytic converter or of the SCR catalytic converter and/or as a function of the ammonia loading of the latter. Moreover, a desired ammonia generation quantity can be determined for a respective regeneration operating phase. The installation and method are adopted for use for motor vehicle internal combustion engines and other engines which are operated predominantly in lean-burn mode.

Zeolite catalysts and systems and methods for preparing and using zeolite catalysts having the CHA crystal structure are disclosed. The catalysts can be used to remove nitrogen oxides from a gaseous medium across a broad temperature range and exhibit hydrothermal stable at high reaction temperatures. The zeolite catalysts include a zeolite carrier having a silica to alumina ratio from about 15:1 to about 256:1 and a copper to alumina ratio from about 0.25:1 to about 1:1.

Zeolite catalysts and systems and methods for preparing and using zeolite catalysts having the CHA crystal structure are disclosed. The catalysts can be used to remove nitrogen oxides from a gaseous medium across a broad temperature range and exhibit hydrothermal stable at high reaction temperatures. The zeolite catalysts include a zeolite carrier having a silica to alumina ratio from about 15:1 to about 256:1 and a copper to alumina ratio from about 0.25: 1 to about 1:1.

The present invention discloses a preparation method of titanium dioxide photocatalytic membrane loaged on metal surface, its main technological process includes: in the electrophoretic solution containing a certain content of titanium dioxide sol or containing binary or multi-component compounded oxide sol of titanium dioxide using the pretreated metal base body as cathode, using graphite, aluminium, stainless steel and inert metal as anode, utilizing electrophoretic mode to form a layer of titanium dioxide membrane on the metal surface under the condition of a certain voltage, drying and calcining to make the titanium dioxide membrane be fixed on the metal surface. Said membrane is high in adhesive strength, and has high photocatalytic activity.

The present invention relates to a low-nitrogen oxide biomass boiler with variable furnace arch structure, including front and rear zoned-air chambers, reciprocating grate, combined arch formed from front arch, rear arch and upper arch and zoned-air nozzles. The bottom portion of the boiler is equipped with front zone air chamber and rear zone air chamber to implement zoned-air distribution, and the reciprocating grate is arranged over the front and rear zound-air chambers, and in the interior of furnace cavity wall between upper arch and rear arch air inlaid several zoned-air nozzles whose inlets are connected with main air channel. Said boiler can extensively utilize biomass fuel, and can obtain good combustion effect.

The invention discloses a burning system of a heavy oil boiler and a method thereof. The burning system comprises an air inlet pipe, an air fan, more than one air box placed on the outer side of a hearth, burnout air spouts formed in each air box, a plurality of burners and igniters, wherein each burner comprises an atomized oil gun, a primary air pipe and a secondary air pipe which are arranged in a sleeving way from interior to exterior, the atomized oil gun comprises an oil pipe and a nozzle which are connected, and the front end of the primary air pipe is provided with a combustion stabilizer; the secondary air pipe is internally provided with a rotational flow device, the front end surface of the nozzle is concentricalally provided with two circles of nozzle holes, each circle of nozzle holes comprises a plurality of nozzle holes which are formed in an equidistant manner, the two circles of nozzle holes are formed in the periphery at intervals, and the hole diameters and spray angles of the outer circle of nozzle holes are larger than those of the inner circle of nozzle holes; and an economizer outlet of the boiler is also connected with an air inlet pipe through a flue gas recirculation pipe, and the flue gas recirculation pipe is provided with a circulating fan. As the burning system and the method are used, the generation amount of nitrogen oxide is greatly reduced, more and more environmental requirements are met, and the burning system of the heavy oil boiler and the method thereof respectively have a relatively wide market prospect.

In a process for producing an SCR catalyst for the selective reduction of NO_x in NO_x-containing exhaust gases of internal combustion engines, a support layer is applied to a substrate body. An iron salt dissolved in a liquid is applied to the support layer in such an amount that no excess of iron salt is present.

An engine block arrangement includes an engine block and an exhaust gas system. The exhaust gas system, viewed in the flow direction of an exhaust gas flow, includes an exhaust gas turbocharger, an oxidation catalytic converter, a feed device for a urea-water solution, a particle filter, and an SCR catalytic converter arranged one behind the other. The exhaust gas turbocharger, the oxidation catalytic converter, the feed device for the urea-water solution, the particle filter, and the SCR catalytic converter are situated together on the engine block along one side thereof, the side being oriented essentially perpendicularly with respect to an output side of the engine block.

A catalytic wall-flow monolith for use in an emission treatment system comprises a porous substrate and a three-way catalyst (TWC), wherein the TWC is distributed substantially throughout the porous substrate and wherein the TWC comprises:

wherein the OSC comprises ceria or one or more mixed oxides comprising cerium and is present in a ratio by weight of OSC to alumina of from 65:35 to 85:15

The invention relates to a double-channel combustor with thick pulverized coal and thin pulverized coal being separated and a use method thereof. The double-channel combustor with the thick pulverizedcoal and the thin pulverized coal being separated comprises a pulverized coal supplying mechanism, a transition channel, an internal secondary air guide duct, an external secondary air guide duct, acombustion stabilizing cavity and a rectifying cavity. The external secondary air guide duct, the combustion stabilizing cavity and the rectifying cavity are sequentially connected. The pulverized coal supplying mechanism comprises an air-pulverized coal pipe and a thick and thin pulverized coal separating device. The air-pulverized coal pipe communicates with the combustion stabilizing cavity. The thick and thin pulverized coal separating device is detachably connected to the air-pulverized coal pipe. The internal secondary air guide duct is coaxially arranged in the outer secondary air guideduct in a spaced manner. The transition channel is coaxially arranged in the internal secondary air guide duct in a spaced manner. The outlet end of the internal secondary air guide duct forms an expanded opening. The angle of the expanded opening is identical with the angle of the combustion stabilizing cavity. By the adoption of the double-channel combustor with the thick pulverized coal and the thin pulverized coal being separated, air can be divided into internal secondary air and external secondary air to respectively enter the combustor, the internal secondary air is combined with the transition channel to sufficiently mix pulverized coal and air, the external secondary air can form a cooling air layer flowing along the wall face of the combustion stabilizing cavity in the combustion stabilizing cavity, and the wall face of the combustion stabilizing cavity is protected against ash accumulation and coking.