RU2189464C2 - Internal combustion engine exhaust gas catalyst converter with regeneration of cleaning - Google Patents

Abstract

FIELD: mechanical engineering; internal combustion engines. SUBSTANCE: external steel and internal cermet walls of housing of catalyst converter are installed with clearance in between which serves as heat insulation. The following devices are installed in housing in tandem relative to inlet branch pipe: soot filter, porous cermet oxidizing and reducing catalytic units, and outlet branch pipe. Housing is divided by blind partition installed between oxidizing and reducing catalytic units. Soot filter and porous cermet oxidizing and reducing catalytic units, each provided with separate end face cover with remover, are installed across housing. Soot filter is provided with crosswise winding of carbon threads and steel wire. Inner spaces of catalytic units are connected by gas bypass collector equipped with nozzle to supply additional gas, mainly, ammonia gas, or ammonia solution or carbamide solution. EFFECT: improved convenience in operation, reduced fuel consumption and improved quality of exhaust gas cleaning. 1 dwg

Description

 The invention relates to mechanical engineering, namely to engine building, and can be used for cleaning exhaust gases of internal combustion engines, in particular diesel ones.

 Known catalytic converter for exhaust gases of an internal combustion engine, comprising a housing with coaxially installed with the formation of a cavity between them porous metal-ceramic oxidizing and reducing catalytic blocks, inlet and outlet pipes with flanges, a channel for supplying auxiliary gas. The auxiliary gas supply channel is connected to interconnected cavities formed between the inner surface of the housing and the outer surfaces of the oxidative porous cermet catalytic blocks (see RF patent 2120554, IPC 6 F 01 N 3/28).

 The disadvantages of the known catalyst is, firstly, that the exhaust gases flow directly to the catalytic blocks, do not have a preliminary purification of solid particles, the blocks become clogged or deactivated; secondly, separate sequential installation of catalytic units for cleaning various components leads to an increase in the total hydraulic resistance of the converter, which ultimately leads to a decrease in engine power and an increase in specific fuel consumption; thirdly, the catalytic blocks, as a rule, have an average pore size in the range from 100 to 200 microns to ensure acceptable dimensions and allowable backpressures, and with this design, part of the solid particles, including soot, with sizes 1.. . 30 microns has the ability to penetrate through the porous walls of the blocks of the Converter.

 Closest to the proposed invention in technical essence (prototype) is a catalytic converter of exhaust gases of an internal combustion engine, comprising a housing with external and internal walls, heat insulation between them, end caps, inlet and outlet pipes, sequentially located relative to the inlet pipe with a particulate filter, porous cermet oxidizing and reducing catalytic blocks, a reactor separated by catalytic blocks and partitions and on individual cavities (see patent of the Russian Federation 2023179, IPC 5 F 01 N 3/28).

 However, when using the known catalytic converter, sufficient operating convenience is not ensured, since during periodic regeneration, all filters and catalytic units are subjected to thermal or thermochemical influence, regardless of their condition. When the catalytic units are deactivated or the particulate filter fails, it is necessary to remove the converter from the exhaust system and completely disassemble the converter. At the same time, a simple diesel engine is inevitable.

 The essence of the invention lies in the fact that in the known catalytic converter of exhaust gases of an internal combustion engine with a cleaning regeneration comprising a housing with external and internal walls, thermal insulation between them, end caps, inlet and outlet pipes, sequentially arranged relative to the inlet pipe with a particulate filter, porous cermet oxidizing and reducing catalytic blocks, a partition dividing the housing into separate cavities, the aforementioned soot th filter and separated by a partition porous cermet oxidation and reduction catalyst units each of which is equipped with individual end cap remover, mounted transversely of the housing. A gas bypass collector located between the internal cavities of the porous metal-ceramic oxidizing and reducing catalytic blocks is additionally introduced into the converter. The gas bypass manifold is equipped with a nozzle for supplying additional gas, mainly ammonia, or an ammonia solution, or a urea solution.

 Porous permeable cermet catalytic blocks can be made using self-propagating high temperature synthesis technology. Like the particulate filter, they are made in the form of glasses, in the bottom of which pullers are screwed onto the threads through the end caps.

 Comparative analysis with the prototype shows that the claimed device is distinguished by the installation of a filter and catalytic units transverse to the housing axis, the presence of individual end caps with pullers, the introduction of a gas bypass manifold between the internal cavities of the oxidizing and reducing catalytic blocks, equipped with an nozzle for supplying additional gas, mainly ammonia, or ammonia solution, or urea solution. Thus, the claimed device meets the criteria of the invention of "novelty."

 In the known technical solutions, no combination of distinctive features was found characterizing the proposed technical solution and used to solve the environmental problem, therefore, the technical solution meets the criterion of "inventive step".

 The technical result is to increase the convenience of operation by ensuring the replacement of failed catalytic units and particulate filters without removing the converter from its installation and completely disassembling it. This leads to a reduction in the downtime of equipment with a diesel drive, to the possibility of organizing the regeneration of catalytic units and filter elements without stopping the equipment in stationary conditions by supplying additional gas, mainly ammonia, or an ammonia solution, or a urea solution, until the exhaust gas reaches the recovery unit, binding of free oxygen occurs, therefore, with a lack of the latter, the recovery processes are more intense and better cleaning takes place from nitrogen oxides.

 The invention is illustrated in the drawing, which shows a longitudinal axial section of a catalytic converter of an exhaust gas of an internal combustion engine with a cleaning regeneration.

 The exhaust gas catalytic converter comprises a housing 1 with an external steel 2 and an internal ceramic-metal 3 walls installed with a gap 4 in the protrusions 5 and 6 on the end caps 7 and 8, mounted on the flanges 9 and 10 of the housing. The gap 4 is also thermal insulation. End caps 7 and 8 are covered with layers 11 and 12 of cermets. In the transverse guides 13,14,15, a diesel particulate filter 16 with crosswise winding 17 made of carbon filaments and steel wire was installed sequentially, transversely to the axis of the housing 1, porous cermet catalytic blocks: 18 - oxidative, 19 - recovery.

 Transverse guides 13,14,15 are equipped with mounting flanges 20,21,22, on which individual end caps 23,24,25 with pullers 26,27,28 are installed. The converter has an inlet pipe 29 with a flange 30 and an outlet pipe 31 with a flange 32. The converter has a blind transverse baffle 33 between blocks 18 and 19. Catalytic blocks, a filter 16 and a baffle 33 divide the reactor into several cavities: the inner cavity 34 of the particulate filter, the intermediate cavity 35 between the surfaces of the particulate filter 16 and the oxidizing unit 18, the internal cavity 36 of the oxidizing unit 18, the cavity 37 of the gas bypass collector 38, the internal cavity 39 of the reducing unit 19, the purified gas cavity 40. In the manifold 38, the cavity of which is connected to the cavities 36 and 39 of the blocks 18 and 19, a nozzle 41 is introduced to supply additional gas, mainly ammonia, or an ammonia solution, or a urea solution. A temperature sensor 42 is installed in the inlet pipe 29. A pressure sensor 43 is placed in the end cap 7 on the particulate filter 16 side. An oxygen sensor 44 is located in the output pipe 31.

 The catalytic converter operates as follows. The exhaust gases flow through the pipe 29 into the inner cavity 34 of the particulate filter 16, are cleaned on the surface of the particulate filter and exit into the cavity 35. Then the gases pass through the walls of the porous cermet oxidizing block 18 and are freed from products of incomplete combustion, enter the inner cavity of the oxidizing block 18, followed by along the manifold 38 into the inner cavity 39 of the reduction block 19. Passing through the porous permeable catalytic structures of the block 19, the gases are oxidized from nitrogen oxides and exit into the cavity 40 gases, and then through the pipe 31 exit the converter. The counter pressure generated by the converter from the sensor 43 and the temperature from the sensor 42 serve as a signal to replace the filter 16. The sensor 44 readings serve as a signal to turn on the supply system through the nozzle 41 for additional gas or solutions to the manifold 38.

 To replace the filter 16 and the catalytic units 18 and 19, their individual covers 23,24,25 are released from the fasteners and a notch is made for the strippers 26,27,28.

 In comparison with the known technical solutions, such a catalytic converter improves the performance of the latter, leads to fuel economy due to the timely replacement of filters and improves the quality of gas purification by supplying additional gas, mainly ammonia, or ammonia solution, or urea solution.

 Comparative analysis with the prototype shows that the claimed exhaust gas neutralizer will have the quality of non-stop operation and a high degree of purification of diesel gases.

Claims (1)

 A catalytic converter for exhaust gases of an internal combustion engine with a cleaning regeneration, comprising a housing with external and internal walls, heat insulation between them, end caps, inlet and outlet pipes, a sequentially arranged particle filter in relation to the inlet pipe, porous cermet oxidation and reduction catalytic blocks, a partition, separating the housing into separate cavities, characterized in that the particulate filter and porous meta separated by a partition lokeramic oxidizing and reducing catalytic blocks, each of which is equipped with an individual end cap with a stripper, are installed across the body, and a gas bypass manifold is additionally introduced into the neutralizer, located between the internal cavities of porous metal-ceramic oxidizing and reducing catalytic blocks, which is equipped with a nozzle for supplying additional gas, predominantly ammonia, or a solution of ammonia, or a solution of urea.