EA031848B1 - Purifying apparatus in the treatment of particulate-containing fluids - Google Patents

Abstract

The present invention relates to a cleaning apparatus for use in treating fluids containing a solid phase. To ensure high throughput of particles and the ability to remain essentially in the open state under operating conditions, the specified apparatus for cleaning (PUL) according to the present invention contains at least one primary particle separator (PPE) for a through flow of fluid, and with it at least one bypass particle separator (OPE) is located, with the main particle separator (PPE) having a higher relative throughput of particles and higher pressure losses than about a bypass particle separator (OPE), the bypass particle separator (OPE) is essentially less susceptible to clogging and its dimensions are chosen so that after complete blockage of the main particle separator (PPE) it is able to handle the fluids in the cleaning apparatus (PUL ), while the flow of fluid through the main particle separator (PPE) and bypass particle separator (OPE) is provided with the ability to control the relative back pressure in the separators, and the main particle separator (PPE) is located in the middle of the specified structure , and the bypass particle separator (OPE) is located around the main particle separator (PPE) design parallel to it in the direction of flow.

Description

The present invention relates to a cleaning apparatus for use in the treatment of fluids containing a solid phase. The present invention also relates to a method for manufacturing, regenerating and operating such a cleaning apparatus.

State of the art

The maximum allowable exhaust emissions for vehicles, equipment and engines are becoming more stringent from year to year, so the use of additional purification methods to maintain emissions below the limit values becomes inevitable. In the case of diesel vehicles, the most difficult task is to achieve emission standards for particles (PM = particulate matter) and NO _x , while emission standards for carbon monoxide and hydrocarbons are fairly easily achieved with oxidation catalysts. In engines reconstitution NO _x can be carried out by lowering the temperature of combustion by the methods used in engine (e.g., EGR = Exhaust Gas Recirculation), which, nevertheless, have an increasing effect on CO emissions of hydrocarbons and PM. Diesel particulate filters (DPF = diesel particulate filter) are typically used in vehicles to reduce the amount of harmful particles during conversions above 90%. Conventional filters are a type of filter with near-wall flow (forced flow through a porous wall), based on surface filtration, in which a layer of the solid phase accumulates on the wall of the flow channel and very few particles accumulate inside the porous wall after initial accumulation. The average pore size in the wall of such filters based on surface filtration is from about 8 to 25 microns, which at normal sizes is enough to remove more than 95% of the mass of the solid phase. These full-flow filters can be replaced by partial-flow filters, which are also known as POC (Partial Oxidation Catalyst) and which provide filtering efficiencies of about 40 to 70%. The advantage that partial flow filters provide is the lack of maintenance regarding unburned ash and excess particles that can be removed from the prefabricated device without using external energy, unlike full-flow filters, in which most of the ash and unburned material remain trapped in filter surface. In the case of full-flow filters, the pressure loss usually increases during operation, even if complete removal of combustible soot / carbon is achieved. The reason for this increase is just the indicated accumulation of unburned ash. With regard to cleaning efficiency, approximately between surface and incomplete filtration are filters based on depth filtering, the cleaning efficiency of which is usually from 50 to 90%, while the calculated optimum value from the point of view of practical application is from about 60 to 80%. Depth filtration filters are usually made of ceramic or metal fibers, or foam, or sintered metal. The fibers in the filter can take the form of a mattress or folded mats. By maximizing the filtration area (thin mats in a folded configuration are similar to air or oil filters), you can maximize the relationship between efficiency and pressure loss. A significant difference between partial flow filters and full-flow filters is that in full-flow filters, the fluid is forced to go all the way through the filter / trap layer, while in partial-flow filters there is also free passage through the filter. Partial flow filters often use strainers, fiber mats, or perforated plates into which particles can move due to pressure drops and turbulence in various channels. It is precisely such a working mechanism and design that distinguish depth filters and filters of incomplete flow from each other, even if nominally the same materials are used for their manufacture. A fiber mat, for example, can function like a honeycomb, forcing the flow to pass through the mat (depth filtration), or as a cell in which the main flow passes through the channels of a cell made of a corrugated and smooth fibrous mat, however, some of the particles remain on the surfaces of the walls (incomplete flow filter). In filters based on the use of fibers, filtration is based on the diameter of the fibers, suitable from the point of view of filtration. In fiber layers or mats, as a rule, there is a very high proportion of voids (porosity> 90%), whereas in conventional filters based on surface filtration (for example, cordierite, SiC or Al titanate), the porosity of the filter wall is usually from 40 to 50 % and in special filters with high porosity reaches 60-70%. In addition, in the case of depth filtration, more particles begin to accumulate on the surface of the filter downstream in the same manner as in surface filtration.

As a rule, the filtered carbonaceous matter of the particles (soot) is subjected to thermal combustion using additional heat. Soot can be oxidized by an intense combustion reaction using oxygen at temperatures above 550 ° C or slowly at lower temperatures (250-350 ° C) using NO ₂ . NO ₂ formed in the oxidation catalyst oxidizes soot at rather low temperatures (> 250-300 ° C), provided that the oxidation catalyst is quite effective.

- 1 031848

Effective oxidation catalysts are able to remove most of the hydrocarbon-containing vaporizing fraction (VOF = volatile organic fraction or SOF = soluble organic fraction) PM. Usually the VOF fraction is from 10 to 40%, but in the case of some engines and under certain driving conditions, VOF particles can be up to 70-90%. Such conditions arise, inter alia, when driving around the city, when using outdated engines and / or when using certain types of fuel. Therefore, there is no explicit way to classify an oxidation catalyst, an incomplete flow filter, or a full flow filter depending on the purification efficiency, since their purification efficiencies overlap with respect to conversion rates depending on operating conditions. In addition, the cleaning efficiency of filters, in which particles accumulate inside the filter phase (depth filtration), and not on the surfaces of the channels, strongly depends on the flow rate and linear velocity. The cleaning efficiency of depth filters usually decreases with increasing linear velocity, and the efficiency of conventional filters of incomplete flow increases with increasing linear velocity (filtering is based on increasing material transfer), which makes clear the functional difference between them. Many depth-based filters allow particles to pass through them at higher flow rates. The cleaning efficiency also depends on the particle size.

Removing the carbon fraction requires a longer residence time in the filter or catalyst. A prior art method based on the use of CRT (soot trap with continuous regeneration) includes a Pt-containing oxidation catalyst, followed by a diesel particulate filter (DPF) without coating or coated with a catalyst (EP 341832). The problems of the passive method using a traditional full-flow filter are associated with situations in which NO ₂ does not form in sufficient quantities, for example, when driving around the city under traffic congestion, while this method requires the use of fuels with very low sulfur content (S <10 ppm ) to minimize sulfate formation in an efficient and expensive Pt-containing oxidation catalyst. In the case of using a fuel with a high sulfur content, an increase in the formation of sulfates (reactions SO ₂ ^ SO ₃ ^ SO ₄ catalyzed by a Pt catalyst) negates the benefits obtained by using such a filter or the filter fills too quickly, which increases the regeneration frequency and the risk of clogging . Clogging the full flow filter (DPF) is not permitted in any case, as this will stop the movement. For this reason, most particulate filters are characterized by active regeneration, the principle of which has been practiced for several decades. Modern automatic control technology and engine management system allows for active regeneration in DPF. In new modern diesel cars, active regeneration of filters can be carried out by periodically raising the temperature, usually in the range from 600 to 650 ° C. If a sufficient amount of soot accumulates in the filter, the start of combustion provides additional heat, which contributes to the complete combustion of soot. Despite carbon regeneration, full-flow filters collect unburned ash, the amount of which should be considered when choosing sizes, lubricants, and possible maintenance operations.

Along with the traditional particulate filter based on the near-wall flow, there are prefabricated devices known from the prior art made of steel wool, ceramic foam, candle-shaped structures, fiber-coated tubular structures for electrostatic separation or the use of water scrubbers. In prior art prefabricated filters, perforated tubular structures are wrapped in fiber mat or metal wool, and one or more of these structures can be installed in a prefabricated full-flow filter. It is characteristic that the fibrous structure is homogeneous without gaps, and the flow is sent to the collecting device through the channels arbitrarily, while it avoids filaments of fibers, and the main direction is on average radial. These aspects are characteristic of depth filters, in which some of the particles accumulate inside the filter material. As a rule, the exhaust gas in these filters moves radially to the inside of the tube, which provides sufficient space for the accumulation of particles inside the collecting device located in front of the filter, on the surface and in the open space of such a device. There are also full metal filters that use, for example, sintered metal or porous metal foam.

The design of the incomplete flow filters was reconstructed from an oxidation catalyst, resulting in an improvement in particle separation by replacing a ceramic or metal cell with structures that contain various openings, teeth or protrusions in the walls and constrictions or filter elements in the flow channels of the cell. The holes or filter elements were constructed by using ceramic or metal strainers, cotton wool or porous materials instead of conventional metal or ceramic walls. Partial flow filters are usually equipped with a collection cell that contains a system of axial open channels in the main flow direction. The main stream is similar to the stream that occurs in conventional catalytic prefabricated devices, but the separation of particles has been enhanced due to the forced partial

- 2 031848 the passage of the flow in the radial direction through the strainers, fibers or sieves in the wall when regulating the flow using a differential pressure. Nevertheless, the radially directed flow of the stream is unsystematic in various directions, with the vector corresponding to the main stream being directed along the axis on average. Another basic principle is that the flow enters at one end and exits from the opposite side at the other end of the cell, which usually has a round or pointed shape.

Particulate filters were regenerated by using not only a combination of throttle control of the engine (adjusting the air / fuel ratio to conditions close to stoichiometric) and additional injection of fuel, but also using electric heating, plasma (SAE Paper 1999-01-3638) or burners, which allow you to add additional heat and burn soot (EP 0070619-1982 and Emissionminderung, Autobilabgase, Dieselmotoren, Nurnberg October 15-17, 1985, Kurzfassungen, VDI 1985). Additional fuel can be injected either into the cylinder (subsequent injection) or into the exhaust system located in front of the oxidation catalyst and / or catalyzed particulate filter. Combustion can also be improved by additives injected into the fuel and containing, for example, Ce, Fe or Sr, which, after distribution on the soot surface, reduce the combustion temperature, for example to about 500 ° C, and also enhance the regeneration that occurs under the influence of NO ₂ .

In particular, in stationary devices it is possible to use adjacent particulate filters, some of which are in the filtration mode, and some in the regeneration mode. The filter loaded with particles is transferred to the regeneration mode and returned after regeneration back to the filtration mode. The flow of fluids is controlled by valves, the use of which, however, can be problematic, and in the case of contaminated objects, malfunctions can occur. Such designs also require large additional filter volumes compared to a single-line system.

The particulate filter catalyst coating can be used to facilitate catalytic combustion of soot (SAE Paper 8500015, 1985), the formation of NO _2, or to oxidize injected fuel to increase temperature. The catalysts that are most effective in the oxidation of hydrocarbons (from fuel), carbon monoxide and NO and which are most reliable are based on the use of platinum (Pt). The formation of NO ₂ in high concentration requires, in particular, the use of Pt, although palladium (Pd) is also effective in the oxidation of hydrocarbons and CO. The catalytic combustion of soot was carried out by using various catalysts that are applied to the filter and which contain, for example, vanadium, copper, potassium, molybdenum and compounds of similar elements. These catalysts usually exhibit good mobility to the surface of solid carbon black or contain mobile oxygen.

Unlike full-flow filters, the regeneration of partial-flow filters is mainly based on passive regeneration using NO2. In addition, in the case of fuels with a high sulfur and ash content, incomplete filters can be used without clogging them, since unburned impurities and sulfates exit the incomplete filter immediately or after some time. For regeneration, it is necessary that the temperatures and the NO _x / C ratio be, on average, high enough that a sufficient amount of NO ₂ can be formed, and the NO2 + C reaction proceeds quickly enough, as a result of which it does not prevent the cumulative accumulation of particles. As regards their design and solid phase accumulation, partial flow filters are different from full-flow filters, which is why other conditions prevail during regeneration. In the early 2000s, the efficiency of the incomplete flow filters was slightly better than the efficiency of the oxidation catalysts, but subsequently it was necessary to raise the efficiency of PM cleaning of such an open filter to about 60 to 70%. Essentially, PM emissions are still 5–20 times greater in the case of full-flow filters (conversion is more than 95–98%), and these filters can be assigned to different categories. Accordingly, the conditions of clogging and the method of regeneration of the filters of incomplete flow are still completely different from the conditions and methods for full-flow filters, the action of which is based on surface filtration. Compared to these filters, very loose oxidation catalysts still provide a lower risk of clogging or lower back pressure. In full-flow filters, the increase in back pressure is significant enough to be measured using conventional pressure sensors. On the other hand, incomplete flow filters show a much smaller and slower increase in pressure loss. A significant increase in back pressure already indicates clogging.

Initially, in the early 2000s, the incomplete flow filters were fully open, while the PM conversion was only slightly higher than 30-40% than the DOC or VOF fractions. Since the incomplete flow filters were improved (PM conversion from 60 to 70%) due to the development of more closed structures, the risk of clogging increased at the same time, and there was even a need to use active regeneration methods that were not initially used in these filters. With the absolute necessity of using active regeneration methods with incomplete flow filters, some of the advantages provided by using filters are not

- 3 031848 full flow will be lost, and the threshold value achieved with full-flow filters will be lower.

Description of the invention

An object of the present invention is to provide a cleaning apparatus for use in processing fluids containing a solid phase that has a high filtration fineness during particle separation and remains in an unclosed state as much as is possible under operating conditions. To achieve this, the present invention is characterized by the features described in the independent claims. Other claims provide several preferred embodiments of the present invention.

To ensure a high throughput for the exit of particles and the ability to remain essentially unoccupied under operating conditions, the cleaning apparatus according to the present invention comprises at least one main PPE particle separator and at least one OPE bypass particle separator is adjacent to it In this case, the main PPE particle separator is characterized by a high relative fineness of filtration during particle separation and a higher pressure loss than the OPE bypass particle separator. The OPE bypass particle separator is substantially less prone to clogging and is sized so that after the PPE main particle separator is completely blocked, it is able to handle the fluids in the PUL purifier, while the fluid flow through the main particle separator and a bypass particle separator, arranged to be controlled by relative backpressures in the separators.

The specified apparatus is preferably completely passive from the point of view of flow control compared with systems known from the prior art, which may include, for example, valves. Preferably, at least one incomplete filter or catalyst is located in the cell next to the full-flow filter or the incomplete filter, which is substantially less prone to clogging and has dimensions corresponding to the capacity for processing the system fluids in the event of a complete clogging of the main unit.

Compared to ordinary full-flow filters or partial-flow filters according to the prior art, a new type of prefabricated device, method and regeneration system ensured functioning without maintenance, regeneration under all operating conditions and ensured low energy consumption during regeneration. The prefabricated device allows the use of a coating with catalytically active components for the oxidation of carbon monoxide, hydrocarbons, nitric oxide (NO) and particles. The ability of the specified cleaning apparatus to not clog and a low pressure loss in it over almost its entire life is achieved using a prefabricated device that contains at least two different filters or catalysts located adjacent to each other, so that a less dense structure operates in situations where a more efficient unit is completely clogged. The distribution of the flow as a whole is provided without adjusting the valves or other types of regulation, since the flow through the collecting devices is directed into the channels under the action of relative back pressure in the separators. Another advantage that the apparatus according to the present invention possesses is the modest expense in its manufacture and operation.

According to one object of the present invention, a catalyst is applied to the main PPE particle separator and the OPE bypass particle separator, which catalyzes the oxidation of hydrocarbons, carbon monoxide, hydrogen, nitrogen oxides, ammonia and / or particles, and / or the reduction of nitrogen oxides with hydrocarbons, ammonia and such reducing agents and / or adsorb nitrogen oxides. In front of the purification apparatus (PUL) according to one of the objectives of the present invention, there is further provided a purification catalyst that is effective for the oxidation of hydrocarbons, carbon monoxide, nitrogen oxides and / or particles and / or in the catalytic removal of nitrogen oxides.

Applications for the present invention include, but are not limited to, the use of exhaust gas, flue gas, and exhaust gas in mobile or stationary devices. In general, a gas mixture is a mixture containing an excess of oxygen continuously or on average. When burning, resulting in the formation of exhaust gas, you can use any type of gaseous (for example, methane, propane, biofuel, gases obtained in the gasification process), liquid (light distillate fuel or fuel oil, diesel fuel, gasoline or biofuel) or solid fuel .

The filter according to the present invention can be used, for example, under conditions of a completely depleted mixture (excess oxygen) or under conditions in which the ratio of components in the mixture is periodically briefly adjusted to achieve a stoichiometric ratio or a ratio corresponding to the enriched mixture. The purpose of regulating the ratio of components in the mixture and the resulting temperature increase is the complete or incomplete regeneration of the filter from particles and accumulated amounts of toxins or adsorbents. Another possible reason for controlling the ratio of components in the mixture is that the system contains other catalysts (for example, an NO _x adsorption catalyst) that periodically require regeneration conditions under which stoichiometry is observed or an enriched mixture is formed.

- 4 031848

The use of full-flow filters and partial-flow filters has been expanded to devices in which temperatures are quite low, for example, when driving around the city constantly, and in which conditions sufficient for passive regeneration are not provided, and accordingly high-performance filters may begin to clog, or in the case of filters an incomplete stream of particles slip in a larger amount into the exhaust gas. In this case, the risk of clogging is inevitable, in particular, in full-flow filters, which use regeneration based on NO ₂ . In any case, full-flow filters will inevitably become completely clogged even with active regeneration, since unburned ash cannot be removed without maintenance and cleaning. This maintenance cycle also depends on the properties of the fuel and lubricant (fly ash). In the event of a malfunction (non-standard fuel, other impurities, malfunctioning engine), clogging can also occur completely unexpectedly.

Several solutions according to the present invention are depicted in the accompanying drawings.

FIG. 1 - apparatus for cleaning, containing a main particle separator and a bypass particle separator.

FIG. 2 is a purification apparatus further comprising a purification catalyst located upstream and optionally perforated plate elements.

FIG. 3 is a prefabricated device in which a bypass particle separator is located in the middle.

FIG. 4 - prefabricated device with three nesting separators, showing a spasmodic change in relative pressure loss.

FIG. 5 is a prefabricated device in which two different separators are arranged sequentially one after another in its bypass and / or main channel.

FIG. 6 is a prefabricated device in which two structures according to the present invention are arranged sequentially one after another, so that the main cell in the first structure is located in the middle and in the second structure on the outer periphery.

FIG. 7 is a channel system formed by a pair of strainers in which the flow can also move in the transverse direction.

FIG. 8 is a partial flow filter design formed by a pair of walls or multiple walls.

FIG. 9 - regeneration of a prefabricated device according to the present invention by using passive (NO ₂ in both separators) and active regeneration (mainly particle separator).

FIG. 10 shows the effect of the particle layer thickness in an open-type particle separator on pressure loss and on the size of the bypass channel.

The abbreviations used in FIG. 1-10:

- incoming fluid

- outgoing (processed) fluid,

- main particle separator (PPE),

- bypass particle separator (OPE),

- flow through the main particle separator,

- flow through a bypass particle separator,

- perforated plate

- reactor / jacket,

- purification catalyst,

- additional energy, such as fuel or electricity, to increase the temperature, ES - energy supply.

One assembly device according to the present invention is shown in FIG. 1. Fluid (1) (usually exhaust gas) enters a reactor equipped with one or more main PPE particle separators (3) and one or more OPE bypass particle separators (4). The main particle separator has a higher fineness of particle filtration and a higher relative pressure loss than a bypass particle separator. Flow control between separators (5) and (6) is mainly determined in a completely static way based on the relative back pressure in the separators, size and degree of filling without the use of control valves. Thus, said apparatus is preferably completely passive with respect to flow control. It is also important that the bypass is defined as a separator, and not just an empty bypass. In addition, this configuration may include a perforated plate (7) located upstream and / or downstream of the separator, which serves to control / control the flow and functions as a coarse filter. The specified apparatus is placed in the reactor / casing (8) (Fig. 2). In FIG. 2 (7 a) - perforated plates upstream of the separators, (7b) - perforated plates downstream. The basic design can also be preceded by a purification catalyst (9) used for the efficient oxidation of gaseous impurities, such as carbon monoxide, hydrocarbons, carbon (particles) and NO, to water, CO ₂ and NO2, which can be used in the regeneration of an incomplete flow filter or an active purification catalyst and which are also likely to play an active role in the reduction of nitrogen oxides (adsorption reduction of NO _x (NO _x trap),

- 5 031848 SCR method (selective catalytic reagent), in which the reducing agent is ammonia and / or its derivatives and hydrocarbons).

Accordingly, the assembled device according to the present invention comprises a nesting structure of two or more cells, in which the flow is distributed through different cells based on relative back pressure. The back pressure in each cell and thereby the flow distribution will be determined based on the configuration of the main components (standard cell, POC configuration (incomplete flow filter, flat full flow filter), dimensions (outer surface area, length, number of holes, wall thickness) and the amount of soot loaded / ash: in dense and solid cells, backpressure increases faster than in open, loose cells, which remain open even under more severe conditions. of the equipment can be operated under conditions in which the full-flow filter is regenerated and filled with ash and clogging of the filter stops moving. Therefore, in this system, a small bypass through the bypass slot is a good precaution.

Therefore, the basic design contains a dense and loose separator / cell. A dense cell is a cell that has a higher particle yield (APE cell with a higher mesh number) and has a higher backpressure. A loose cell is a cell with lower particle yield and lower backpressure. Thus, the assembly device and method include a denser and less dense cell. If the dense cell is a full-flow filter, the less dense cell may be an open type particle separation (APE) structure. In the case where the denser cell is an APE design, the less dense cell is, for example, a conventional flow converter or an open direct channel cell. The flow converter is, for example, a conventional oxidation catalyst, which, when operating as a bypass cell, is preferably a metal ring element. Essentially, in this case, the flow converter accumulates fewer particles and is less prone to clogging than PPE.

If the dense cell is a regular flow converter with a mesh number of 1200 cpsi (cells per square inch), the less dense cell is, for example, a conventional flow converter with 400 cpsi. Particle separation efficiency and backpressure correlate with each other, but at the same time, clogging of the cell increases in direct proportion to cleaning efficiency and backpressure. In addition, the length of the dense and loose cells can be different.

One of the special solutions is that these cells are similar, but a loose cell is much shorter and therefore does not clog so easily, and when a longer cell becomes clogged, more and more fluid begins to flow through the shorter cell. In a shorter cell there is greater turbulence. This concept can mainly be used in open structures, since filtration efficiency and the tendency to clog full-flow filters are a consequence of a closed structure.

The cleaning device can be placed in the reactor (8) (Fig. 2), which is, for example, an ordinary lined catalytic converter, in which the cell may not be insulated or wrapped in an insulating / installation mat and / or heat shields. In addition, the reactor can be combined with a silencer, which can also include other functional units (deNO _x nitrogen oxide oxidation or decomposition catalyst (SCR, depleted NO _x trap catalyst (LNT)), a full-flow filter, and additional elements related to the operation of the above blocks). The shape of the cell can be round, oval or annular, and in all cases the flow can be axial or radial, or in some cells axial, and in other cells radial.

According to one of the objectives of the present invention, the main PPE particle separator is a full-flow filter, such as a wall flow filter, and the OPE bypass particle separator is an open type APE particle separator having a mesh structure provided with permeable walls with open channels between them. According to one of the objectives of the present invention, the main PPE particle separator is an open type particle separator and the OPE bypass particle separator is a flow converter.

According to one object of the present invention, the main PPE particle separator is dimensioned such that the through-flow is more than 70%, preferably more than 85% in the unloaded state and / or during normal particle charges.

According to one object of the present invention, the particle separation efficiency of the main PPE separator is from 50 to 100%, preferably from 60 to 99%, and the efficiency of the OPE particle bypass particle separator is from 20 to 90%, preferably from 30 to 70%. The main particle separator (PPE, 3) is, for example, a full-flow filter, a surface filter or a depth filter with high particle separation efficiency (usually in the range of 80 to 100%) or an open type particle separator whose PM separation efficiency (for example, from 50 to 80%) higher

- 6 031848 than the efficiency of the bypass particle separator (OPE, 4, PM separation efficiency from 20 to 70%).

According to one object of the present invention, the main PPE particle separator is a wall-mounted ceramic filter, and the OPE bypass particle separator is an open-type metal and / or ceramic particle separator (APE). A fully in-line filter is usually a cell filter in which a fluid, through an external force, passes through a filter wall. The material consists of cordierite, silicon carbide or aluminum titanate, or a similar ceramic material, or a mixture thereof. A full-flow filter can also be a depth filter made of ceramic foam, fiber (metal, ceramic material, metal oxides or mixtures thereof), sintered metal, or similar effective particulate filters. When the PPE is an open-type particle separator, another open-type particle separator, such as OPE, is located adjacent to it, the relative PM separation efficiency and backpressure of which are lower than the PPE parameters indicated.

The OPE bypass particle separator is generally a particle separator, the back pressure per unit volume of which is substantially lower than the back pressure of the main particle separator. This condition is realized, inter alia, in such a way that the OPE is an open type particle separator, while the PPE is, for example, a full-flow cell filter. The open type particle separator has open channels passing through the cell, which allow you to keep the specified structure unclogged even when the PPE begins to clog. Flow control in the specified device is completely passive. Since the relative OPE backpressure is lower than the PPE backpressure, an exceptionally small amount of OPE is needed to ensure that the bypass design works and to ensure that the backpressure does not become too high even with full PPE plugging. Since OPE is small in size and in its normal state only part of the fluid passes through it, the efficiency of PM separation of the entire system remains at a high general level.

The present invention differs from other bypassed systems in which the flow is usually controlled by valves. Designs that include an empty bypass channel or tube are also substantially different from the present invention because it is understood that the bypass channel has a capture efficiency / capture surface, a catalytic surface, and a particle separator / catalytic cell. Of course, the design provided with bypass channels in a minimal configuration will be such a design in which the bypass channel contains an empty tube or an annular channel, but even in this case it is important to adjust the relative backpressures by selecting the flow distribution parameters in the system, as described in the invention, so that the back pressure remains within certain limits and does not impede the continuation of the movement.

Open Type Particle Separator (APE) refers to designs that, instead of the dense porous or fibrous structure of full-flow filters, are provided with open channels, in which the adhesion of particles to the walls along which the flow is running has been accelerated by using tortuous, sometimes tapering and expanding portions of the channels, containing penetration paths through the walls, which helps to equalize the pressure drop between adjacent channels. Such conditions contribute to the adhesion of particles to the walls, which function as trapping surfaces and are preferably made of strainers, membranes or fiber mats (or combinations thereof) made of metal or ceramic. As a rule, capture efficiency is in the range from 40 to 80%, which is significantly lower than the efficiency achieved using full-flow cell filters.

One of the prefabricated devices of the present invention is depicted in FIG. 3, in which the bypass channel is located in the middle of the main cell. In this case, the main cell, characterized by high capture, is located outside, making it easier to cool, and heat more easily spreads into the external environment. In the technical sense, it may be easier to make a small loose cell located in the middle than a cell with a corresponding outer surface located on the outer periphery.

According to one object of the present invention, the main PPE particle separator is located in the middle of the structure, and the OPE metal bypass particle separator is arranged parallel to the flow direction around the main PPE separator structure. According to the present invention, it is also possible to place more than two separators in parallel (FIG. 4). In FIG. 4 6a - flow through the 1st bypass particle separator, 6b - flow through the 2nd bypass particle separator. Relative pressure loss (per volume, per length): 3> 4a> 4b. In this case, the density, separation efficiency and / or relative backpressure of the cells gradually become less intense, as a result of which most of the flow first passes through the densest separator in the unloaded state, but as the denser separators fill up, the flow deviates more and more and flows into the next a less dense cell and, finally, into the loosest separator. In addition, as a rule, the relative volumes and areas of capture also decrease as the separation efficiency decreases. This type of apparatus can be made, for example, of a structure in which

- 7 031848 the main particle separator contains a full-flow filter, the 1st bypass particle separator contains a dense APE and the 2nd bypass particle separator contains a loose APE, or a flow cell, or an empty bypass channel that remains open in any situation.

The main and / or bypass channel can also be equipped with sequentially located separators with other properties (Fig. 5). In FIG. 5 3a - 1st primary particle separator, 3b - 2nd primary particle separator, 4a - 1st bypass particle separator, 4b - 2nd bypass particle separator, 6a - flow through the 1st bypass particle separator, 6b - flow through the 2nd bypass particle separator. Relative pressure loss and separation efficiency: 3b>3a>4b> 4a. Properties 4a (3a) and 4b (3b) can also be reversed. In addition, the lengths of each block may vary. This design also allows more precise control of back pressure and flow distribution. In front, you can place, for example, a loose cell, and a denser cell can be installed downstream of such a loose cell, as a result of which a suitable backpressure is achieved, and more particles are collected in a dense section downstream. Correspondingly, the particles do not fill the separator from the front, but from the rear, as a result of which, when the section upstream is clogged, there is still space in front for collecting and storing particles. If in this design a denser cell is located upstream, more particles are collected in the portion of the cell located upstream, thereby it can be more easily regenerated with the help of external energy supplied to its front part (the heating problem is solved by electricity or by injection fuel). You can also sequentially place the APE and the full-flow filter, for example, as a PPE. Successive designs also make it possible to use a catalytically more active coating in the upstream region, which allows to obtain in the dense cell downstream, in particular in such a defined channel, more NO ₂ , or the upstream catalyst is an effective oxidizing agent for hydrocarbons in the case of active regeneration. Thus, the separator upstream can also be a flow cell. This design can be used to replace the upstream purification catalyst.

According to one solution of the present invention, the flow is guided through the channels through the cells while regulating fully static sections of the cells. Regeneration will also occur without external flow control. If the cell is in the process of clogging, a smaller flow passes through it, making it easier to heat. Along with the static state, flow control or regeneration can also be used, for example, by electric heating in a dense cell. For such a design, external heating is particularly suitable, since conventional heating carried out by fuel enrichment is more difficult to communicate through a fully clogged cell. Additional energy allows you to simultaneously heat the entire system, the main particle separator as a whole, part of the PPE or ignite the carbon-containing substance present in the main particle separator. Particles mainly consist of carbon and hydrocarbons, the ignition of which can be carried out using additional energy or a spark. Hydrocarbons can ignite locally if the temperature rises to more than 150 to 300 ° C, and the same applies to carbon if the temperature locally rises to more than 400 to 600 °, depending on the structure of soot and possible catalytic activity during carbon burning . The high concentration of NO ₂ present at the same time can also contribute to this ignition. Of course, regeneration can be based on fully or partially passive regeneration under the influence of NO2.

According to one object of the present invention, the PUL cleaning apparatus is dimensioned such that the pressure loss can increase by 5 to 50 times, preferably 10 to 20 times, while the entire flow flows through an OPE bypass particle separator compared to the cleaning apparatus A PUL that is particle free. Of course, in the apparatus for cleaning it is necessary to maintain the resulting back pressure at the lowest level, but the apparatus according to the present invention has sections whose dimensions are selected in this way taking into account relative back pressures.

The flow rates through the cells are configured so that the main stream in the normal state passes through a more efficient, denser cell, as a result of which the specified cell must be significantly larger in volume than the less dense cell. A less dense cell has smaller dimensions, but is designed in such a way that the back pressure allows the engine to work and carry out the movement of the flow, even if almost all or all of the flow must pass through the specified cell. However, in the event of clogging of the main cell, the back pressure will be several hundred mbar at normal sizes. Of course, it is impossible to provide a large soot storage capacity for a small loose cell, as a result of which the PM conversion remains at a relatively low level (30-50%) if the entire flow changes direction and passes through the bypass cell. A bypass particle separator can also be used to keep the engine / apparatus running without stopping and to carry out, for example, active regeneration when possible. Of course, flow control can be carried out by using actuators and valves, working, for example, on the basis of back pressure, in which case the system is no longer passive. In one application of the present invention, flow control will completely pass

- 8 031848 active, but PM regeneration can be carried out using either active or passive methods.

Special solutions may include those solutions for which cell sizes are more similar. One such system may contain a full-flow filter located adjacent to one line (PM conversion> 98%) and an open-type particle separator (PM conversion from 40 to 50% at such specific sizes), thereby the full PM conversion will be higher (for example, from 80 to 90%) when passing the stream mainly through a full-flow filter and lower (from 60 to 70%) when passing the stream mainly through an open particle separator. This design provides time and the possibility of regeneration or maintenance of the system without stopping the flow, and at the same time, maintenance is possible at any time. There is the possibility of using the OBD system (on-board diagnostic system), which is activated when most of the flow passes through the bypass filter, while it is impossible to regenerate under operating conditions. Thus, the described apparatus for cleaning provides the possibility of maintenance.

One of the open-type particle separators described in the examples consists of corrugated mesh filters, in which a mesh filter fold deviates from the main flow direction and adjacent / superimposed mesh filters are located at mutually different angles with respect to the main flow direction (Fig. 7 and 8). In FIG. 7 A-design gas or fluid, axial direction, B - catalytic coating on the surface of the collection device containing the strainer / foil. The crease used in the incomplete flow filter may have a height (h1 and h2) selected taking into account the design, methods of controlling backpressure and emissions (Fig. 8). In FIG. 8 B is the angle of the diagonal crease, G is the 1st direction of the crest of the corrugated foil, D is the width of the strainer, E is the 2nd direction of the crest of the corrugated foil, G is the angle of the diagonal crease relative to the flow, 3 is the wall 1 (high crest), And - wall 2 (low crest), K - non-corrugated wall. The height of the fold in different strainers can be the same or uneven. The height may vary from 0.2 to 200 mm, preferably it is from 0.8 to 3 mm. The angle of the diagonal crease can also vary from -90 to + 90 °, preferably it is from -60 to -20 and from +20 to + 60 °. Angles with a minus and plus sign refer to angles in opposite directions relative to the direction of the main stream. It is advisable to use one material for a diagonal corrugated mesh filter, to make a pair of mesh filters from it by turning one of the mesh filters inside out so that the crests of the folds extend in different directions and provide support to each other. This design preferably allows you to get APE made of the same strainer. The ratio of the height and width of the folds can be changed in a very wide range by using either low and wide folds, or high and narrow crests of the folds. These diagonally pleated mesh filters are made by running a straight mesh filter through gears with spiral teeth, which makes it possible to obtain the pleated texture used in the present invention as PPE or OPE. A non-pleated mesh filter or permeable wall may also be located between two diagonally pleated mesh filters, whereby a reduction in channel size increases material transfer and particle capture. Between the permeable walls, there may also be an impermeable foil or wall for enclosing the components in a shell in order to prevent them from mixing with each other. This allows you to regulate active or passive regeneration. You can optimize the height of the fold depending on the object: very dirty objects have a large fold height, very clean objects have a lower fold height.

In the APE depicted in FIG. 7 and 8, the thickness of the filter screen is from 0.01 to 5 mm, preferably from 0.1 to 1 mm. The size of the holes in the strainer is from 0.05 to 10 mm, preferably from 0.1 to 2 mm.

The strainer may be woven or may be otherwise knitted. A wide range is due to the presence of very diverse objects or goals. For very dirty objects, the strainer is less dense and the crease has a higher height, for clean objects the strainer is denser and the crease height is small. You can use a mesh filter with a very fine thread and / or with large hole sizes in the case of a corrugated mesh filter and a very dense mesh filter in the case of a flat mesh filter, which makes it possible to fold the mesh filter even at a rather large fold angle (40-80 °). Instead of or in conjunction with a strainer, fiberboards or membranes can also be used that are processed to form an appropriate structure, the walls of which have corresponding holes / thickness, and which is partially permeable to the fluid. The assembly device shown in FIG. 7 and 8 may also contain additional or optional flow barriers, narrowing / expansion or protrusions / blades, which increase material transfer and capture efficiency and form an assembly device for separating open-type particles.

- 9 031848

If the PPE is made of a ceramic material (cordierite, SiC, silicon nitride, aluminum titanate or the like), the OPE may be a metal APE; Thus, in the indicated design, a more efficient ceramic and less efficient metal particle separator are arranged side by side on one line, while the flow passing through it is controlled mainly in a static way, without active regulation, based on pressure loss. The ceramic cell is preferably located in the middle, and around it is an annular metal OPE, which can be made, as described in the previous paragraphs, of corrugated metal structures (mesh filters). Ceramic particulate filter is not easy to produce in the form of a ring structure, while in the form of a thin ring structure it also does not have good strength. This allows you to use the good properties of each structure. This structure also allows different regeneration methods to be used for different separators. PPE can be subjected to active regeneration, which is based on fuel injection and / or temperature increase through the use of electricity. In this case, you can also set the A / F ratio at a lower level, which will also allow to increase the temperature.

PPE and OPE can be completely or partially coated in the flow direction with a porous substrate that functions as a primer for active compounds that oxidize CO, hydrocarbons, hydrogen, ammonia or carbon. Hydrocarbons may also include functional groups containing oxygen, nitrogen or halogens. The coating on the APE is preferably carried out so that the openings of the strainer remain at least partially open in at least one of the strainers. Alternatively, there is no coating at all in this design, therefore it serves only as an APE and a silencer. Additionally or optionally, the catalyst can catalyze the reduction of NO _x with hydrocarbon or ammonia, absorb nitrogen oxides (reduction under enrichment conditions) or oxidize ammonia. Typically, the catalyst contains oxides of aluminum, silicon, titanium and / or zeolites in the substrate. The coating thickness is from 1 to 500 microns, preferably from 5 to 40 microns. The surface area of the coating is determined by the starting materials used and ranges from 1 to 1000 m ² / g, usually from 20 to 300 m ² / g. The coating can be applied to the separators using various suspensions, sols and / or solutions by immersion, pumping, soaking and / or spraying. Open filters can be sprayed onto open screens, the screens from a pair of screens being separated from each other and only then rolled up to form a screen filter and an APE prefabricated using APE. This ensures that the openings of the strainer remain open. As for the APE, it provides a mechanically strong coating that still leaves the openings of the strainer open. The coating can also be fully or partially carried out using evaporated starting materials (chemical vapor deposition from gas or vapor, Ale methods).

Active metals used in catalytic coatings include, for example, noble metals such as platinum (Pt), palladium (Pd), iridium (Ir), and / or rhodium (Rh), and / or iridium (Ir), and / or ruthenium (Ru). The active components can be added to the catalytic composition of the coating by absorption (dry, wet or chemisorption methods) or by mixing them with a suspension, solution or sol used for coating. Before mixing and applying the suspension, the active components can be pre-absorbed by the starting catalyst particles. Methods of coating and / or absorption include the use of water or other solvents or mixtures thereof, mainly in the liquid phase.

The amount of active metal, for example a noble metal, is from 0.01 to 10 g / dm ³ , preferably from 0.1 to 3 g / dm ³ . If there are several structures in series, the amount of active metal in the first structure upstream may preferably be from 0.8 to 2 g / dm ³ and in the next structure / structures downstream from 0 to 0.8 g / dm ³ . The task in this case is to provide the same design, for example, with a large amount of Pt from the side on which the inlet side is in the flow direction, which, thus, allows to obtain a larger amount of NO ₂ in this section. On the output side, there is not enough time for equally intense Pt catalysis of NO oxidation in the case of passive regeneration, as a result of which the load is lower. On the output side, other active components, such as Pd, may also be present. This design can be used in conjunction with a purification (oxidation) catalyst located upstream.

The active component is selected taking into account the application. Catalytic platinum coatings with a suitable support can be used to activate the formation of NO2, which activates particle combustion and purification regeneration, for example, in diesel-powered devices. All Pt-containing catalysts do not provide a high NO ₂ content, since the use of suitable additives (for example, vanadium) in the substrate prevents the formation of NO 2 and thereby sulfates. Reducing the formation of NO2 used for devices in which the regeneration is carried out fully active method (by injection of fuel and / or engine throttle) and when necessary to minimize emissions of NO _2. Pd can be used as active

- 10 031848 component, when the catalytic coating is designed to catalyze the oxidation of CO and hydrocarbons without the formation of NO2 and at high temperatures under operating or regeneration conditions.

Activators used in the substrate may include, for example, vanadium (V), tungsten (W), iron (Fe), zirconium (Zr), cerium (Ce), lanthanum (La), manganese (Mn), cobalt (Co) , barium (Ba), strontium (Sr) and / or nickel (Ni). The substrate may also consist mainly of compounds of these activators. For example, by absorption, conventional NO _x adsorbing compounds can be added to the coating to adsorb nitrogen oxides in the lean mixture and reduce their content in the rich mixture.

In full-flow filters according to the present invention, it is possible to use coatings of a similar type as in APE, or coatings, preferably applied in the form of a sol, which covers the fibers or pores of the capture unit with a thin layer of catalyst, without clogging the channels or increasing back pressure in this area. A sol is a liquid in which small particles are dispersed, the average diameter of which is from 5 to 1000 nm, preferably from 15 to 100 nm, and the particle size evenly covers even small pores and fibers. Particles can be, for example, oxides of Al, Si, Ti, Zr, Ce, Mn, V, Cr, Co, Sr, La, Y, Pr. The amount of coating is usually from 0.1 to 30% based on the weight of the full-flow filter, and the active component is usually a noble metal, such as Pt, Pd, Rh, or a mixture thereof. In other cases, you can use the same activators, active metal loading / methods of introducing additives and processing methods that are used for coating other catalysts.

Compounds (V, Cr, Mn, Co, Sr), activating catalytic combustion / ignition of soot, and thermally stable oxides (La, Y, Zr) protecting the separators from thermal stress can be used in separators. One application of the present invention is that a full-flow filter is coated with sol, and APE is coated with a suspension of a conventional catalyst containing larger particles (>> 100 μm). This operation results in optimal coverage on both separators. For example, a suspension containing large particles clogs full-flow filters with small pores, or, which is undesirable, the coating is filtered only on the surface of the separator. The use of a suspension of a conventional catalyst (for example, an oxidation catalyst) allows to obtain a thicker catalyst layer on the surface of the flow cell.

One of the coating strategies of the present invention is that a heat-resistant coating and / or coating that directly or indirectly (by the formation of NO2) catalyzes the combustion of soot is applied to the separators. The main and bypass particle separators can also be provided with various coatings. For example, a thermally durable coating (containing, for example, La and / or Zr) may be located on the main particle separator, since when the particles become clogged and subsequently burned, this separator heats up more than the bypass particle separator. At the same time, a bypass particle separator can be provided with a coating that directly or indirectly (using NO2, a higher Pt content, and also due to the absence of compounds that prevent the formation of NO2) catalyzes the combustion of soot.

The upstream purification catalyst includes the use of coating compositions similar to those used in APE. Typically, the purification catalyst differs from APE in that the amount of coating used is usually greater, i.e. from about 50 to 500 g / l, and the amount of active metal is also greater, usually from 1 to 5 g / l. The bulk of the purification catalyst is a ceramic or metal cell with a mesh number of from 1 to 2000 cpsi, preferably from 50 to 600 cpsi.

Blocks coated with catalysts can be processed during the production process under static or dynamic conditions using oxidizing and / or reducing gas mixtures, which may include air, oxygen, hydrogen, carbon monoxide, ammonia, exhaust gas, hydrocarbons, water or any inert gas. This treatment can also be used to obtain various mixed oxides formed between the compounds for coating by applying suitable starting materials, particle sizes and finishing conditions.

The APE contains a strainer fixed by welding, soldering, or a metal nail or spike is inserted around the mesh screen that can be connected to the inner tube. Heat sources (electric heating systems or devices) associated with active regeneration can also be combined with these structural elements responsible for the mechanical connection. If the PPE contains a ceramic full-flow filter, it rests on a film or sheath using a flexible mounting mat that can withstand high temperatures. Thus, around the cell in the middle is the installation mat and casing, and the APE located around the cell does not need a separate bulky installation mat, which thus facilitates the production process of this design.

Thus, the apparatus according to the present invention allows, in particular, to reduce the amount of emissions of solid particles contained in the exhaust gases. The prefabricated device is a separation apparatus designed, inter alia, for diesel fuel

- 11 031848 devices in which a favorable outcome of passive or active regeneration is ensured by the large use of a bypass particle separator whenever conditions are unsuitable for regeneration. This design is particularly well suited for devices with low temperatures, for example when driving around the city, and also when it is impossible to provide regeneration all the time in the case of passive or even in the case of active regeneration. In order to optimize fuel efficiency, the regeneration of the separators (main and / or bypass particle separator) is preferably carried out by using as much passive regeneration as possible. Cleaning, or part of it, can also replace some of the common elements used in jamming. Cleaning can be carried out in a silencer, similar to those used for conventional oxidation catalysts and particle separators.

Thus, particles collected on separators regenerate passively and / or actively by using external energy (fuel, electricity, etc.). In the case of exhaust gases containing excess oxygen, a purification catalyst (e.g. DOC = diesel oxidation catalyst) that oxidizes CO, hydrocarbons and NO can be installed upstream of the apparatus. The resulting NO ₂ slowly oxidizes carbon-based particles. DOC can be located in the same container or as a separate unit upstream of the reactor. DOC can also be placed inside the inlet tube. The temperature of the separators can be raised using external sources by burning hydrocarbons or by using other exothermic (heat generating) reactions that occur in the catalyzed separators or in the purification catalyst. Additional heat is generated by supplying fuel to the exhaust gas and / or by subsequent injection into the engine. At the same time, the amount of combustion air can also be reduced by reducing the A / F ratio. Additional heat to regenerate the catalyst structure can be obtained by electric heating, burners and / or plasma and / or by some other method that allows you to heat the specified structure and / or soot. Particle accumulation can also be enhanced by electrostatic methods, by using pairs of strainers in a charged state, acting as trapping strainers, and by isolating the strainers from the rest of the structure and from each other. Particle regeneration using a prefabricated device according to the present invention can also be improved by the use of additives that promote soot combustion (FBC = fuel catalyst) and which contain, for example, compounds based on Fe, Sr and / or Ce. Due to the loading of additives and the simultaneous use of active regeneration, carbon particles can ignite more easily.

When burning particles, it is necessary to obtain such an amount of heat that the temperature of the separator instantly rises to a temperature of more than 500-600 ^o C, sufficient for thermal combustion, which can also contribute to the catalyst present in the separators or entrained in the exhaust gas. If it is necessary to use the thermal energy of the particles present in the separator, it is important that the separators capture the particles in an amount sufficient to heat and maintain combustion for as long as it takes to regenerate the separator completely or a sufficient part thereof.

One of the advantages of the present invention is achieved by a design in which a denser separator (cell) is installed in the middle, and a bypass separator is located around it outside. In this case, the heat loss is small, since the external cell functions as an insulator, and the oxidation of particles present in the middle separator can begin with minimal additional energy, unlike systems that contain only a particulate filter that directly communicates with the surrounding air through the surface. Thus, regeneration using external energy can be applied to a middle separator, as a result of which external energy and heat of combustion are distributed and collected in concentrated form to enhance regeneration.

Of course, the described construction can be implemented not only in a nested configuration, but also when using adjacent separators, which are, for example, round or pointed and in which the flow can be axial and / or radial.

Accordingly, the idea is that separators that differ from each other in particle output (filtering capacity) will be installed side by side on the same line so that when a more efficient separator becomes clogged, the flow is directed through a less efficient separator under the action of natural changes in pressure loss as described above. Thus, blocks that can be placed side by side on the same line in decreasing order of cleaning efficiency are 1) filters based on near-wall flow, 2) depth filters made of fibers, sintered metal, ceramic / metal foam, 3) open-type particle separators (APE) and / or 4) traditional catalytic cells (ceramic or metal, flow). A fifth unit may also be present in the form of an empty bypass tube and channel. In addition, constructions of a similar type can be installed in parallel, but the cleaning efficiency is controlled by the cell length, pore size of the wall, size / shape of the channels, or other variables that affect filtration.

- 12 031848

The relative cleaning efficiency is the efficiency that can be obtained with appropriate designs or the size of the separator, filtration area and / or weight. Within each category, cleaning efficiencies can be evaluated as described above, or even more accurately. For example, in filters with near-wall flow, the cleaning efficiency increases with increasing wall thickness and decreasing pore size of the wall. In APE, the cleaning efficiency can be adjusted using the size / shape / material and volume of the channel. The efficiency of cleaning from the solid phase for filters with near-wall flow is high, i.e. from 90 to 100%, usually from about 97 to 99.8%. In depth filters, PM cleaning efficiency is from about 50 to 95%, usually from 70 to 90%. In open-type particle separators, PM cleaning efficiency ranges from 30 to 80%, usually from 40 to 70%. In conventional catalytic cells, PM conversion is determined by the VOF content and is from about 10 to 60%, usually from about 20 to 40%. Accordingly, the assembled device according to the present invention can be characterized based on the indicated ranges of PM conversion and relative back pressure.

The linear velocities in different separators are usually not the same: in full-flow filters, the relative pressure loss is higher and thus the linear velocity is lower than in open-type separators or catalytic cells. In the present invention, all blocks were defined as particle separators, since even a fully open catalytic cell exhibits some oxidative activity, which helps to remove hydrocarbons and thereby the VOF fractions from the particles. If the bypass cell would simply be an empty tube without catalytic material, under normal operating conditions it would be impossible to remove even this VOF fraction, resulting in a system that is different from the solution according to the present invention. The VOF fraction can be quite significant and varies over a wide range, from about 10 to 85%, usually from about 15 to 40%, which leads to a difference in particle separation efficiency.

The apparatus according to the present invention is preferably designed for conditions that are characterized by low temperatures for sufficiently long periods of time, as a result of which the passive regeneration of the separators is insufficient. Such a condition, for example, in the case of vehicles, takes place with constant driving around the city or with some other type of driving at low speeds. Unlike a full-flow filter, a properly designed open-type filter does not clog even under the indicated conditions, but the ability to trap particles decreases and more particles leak out as the flow deviates more and more towards the bypass channel. The use of a bypass particle separator allows periodic regeneration of the main particle separator even at constantly low speeds.

Passive regeneration of separators requires the use of high Pt loads with a suitable substrate composition in a large oxidation catalyst located upstream and in the separators. Since clogging of the entire apparatus can be prevented by using a bypass element, the amount of expensive precious metal can be reduced to some extent, which provides great commercial benefits achieved by saving strategically important starting materials. Most Pt is needed to increase the NO ₂ content in the temperature range from 200 to 300 ° C. The use of slightly lower Pt charges additionally makes it possible to regenerate separators at temperatures above 300 ° C, since the bypass channel can compensate for the effects of these conditions. It also helps to reduce NO ₂ emissions, while a smaller amount of oxidation catalyst provides less back pressure to provide an additional reduction in fuel consumption. One of the tasks is to combine the advantages of using a passive method and a filter bypass element in the apparatus according to the present invention. When working, when possible, passive regeneration ensures that the back pressure is kept at a low level and also does not consume external energy.

Although APE is not as sensitive to sulfur contained in the fuel (<10 ppm S) as full-flow filters, and in particular CRT systems, it is advisable for the fuel to contain as little sulfur as possible. However, this is not possible in all intended devices. The use of a bypass particle separator reduces the activity of the oxidation catalyst (lower Pt loading), thereby simultaneously reducing the formation of sulfates. Accordingly, the apparatus according to the present invention is also applicable to fuels with a higher sulfur content, since PPE can be dense and efficient, however, while OPE serves to ensure the passage of fluid and limit back pressure, even in the case when particles will quickly accumulate in PPE and its back pressure will increase. A regulatory strategy should be developed depending on driving (operating) and fuel conditions.

Active regeneration in full-flow filters is regulated by using pressure sensors located upstream and downstream of the filter, as well as using temperature sensors. Combining the data on the pressure drops with the data of the three-dimensional characteristics of the engine allows you to start active regeneration at a time when it is most easily implemented and when it is the most energy efficient. Of course, such methods can be used.

- 13 031848 also with an apparatus according to the present invention or with parts thereof. In the case of a full-flow filter (PPE), this is natural, but in the case of APE, a fairly low backpressure is observed even at high solids contents, as a result of which the accuracy of pressure sensors can become a limiting factor. Therefore, the apparatus can be equipped with back pressure sensors installed throughout the system or throughout the main particle separator, which in practice is one and the same. The use of active regeneration in conjunction with a full-flow filter is most reasonable to implement using a previously developed strategy. Pressure and temperature sensors can also be used for OBD purposes to warn if the device is in the process of clogging or overheating and requires maintenance.

Upstream of the purification apparatus, it is also possible to supply not only hydrocarbons and known fuels, but also other oxidizing and reducing compounds such as ammonia, urea, ozone, hydrogen peroxide, air, oxygen and / or water, pure or in mixtures. This allows you to activate the reaction of NO _x and / or particles, to ensure purification and to regulate the stoichiometry of the reactions. The structure according to the present invention can undergo passive and / or active regeneration (Fig. 9). In FIG. 9 7a - 1st perforated plate, 7b - 2nd perforated plate, 10 additional energy (fuel or electricity) to increase the temperature. In the main filter, which is characterized by a greater predisposition to clogging and a greater need for regeneration, you can use active regeneration, which is based on the use of external energy (fuel or electricity). When the main particle separator is clogged, less and less fluid passes through it, and less heat is required to heat the separator and the fluid compared to the state in which most of the fluid passes through the separator and cools it during regeneration. In this case, in the case of using external energy in engines running on a lean mixture, the A / F ratio can be changed to a value of λ, approximately 1, so that the temperature of the exhaust gas rises. Thus, the regeneration of the main particle separator will be based on the regulation of the A / F ratio and at the same time additional heating, while the regeneration of the bypass particle separator will be improved by regulating the A / F ratio and increasing the temperature caused by this regulation. In other cases, the regeneration of both separators occurs passively whenever the NO2 / C ratio and temperature are suitable (> 250 ° C) for the reaction of NO2 + C.

Examples.

Typical prefabricated devices and flow distribution can be modeled based on data known from prior art cell backpressures. For each type of cell, there are parameters defined in the calculation equations in which the pressure loss experienced by the exhaust gas depends on the configuration of the cell, the size of the cell, the number of mesh, the amount of substrate, temperature and flow rate. Such equations describing the pressure loss in the catalyzed cells are well known. Typical calculations include iterating flow rates to establish the same pressure loss across all adjacent cells, an effect that by its nature equalizes the flow in these structures. In such equations, clogging can be determined solely from the point of view of geometry by treating soot in the same way as with the substrate, and varying the thickness of the substrate. The last equation is probably only suitable for small PM downloads. Iterative calculation for neighboring cells was carried out using spreadsheets based on Excel, including equations describing pressure loss for each type of cell.

In a typical calculation, the amount of exhaust gas emitted from this engine is 770 kg / h. The maximum exhaust gas temperature is 500 ° C, and operating conditions vary from the outdoor temperature to the indicated maximum temperature at which pressure loss calculations were performed.

Example 1. The main cell was an open type particle separator made of diagonally pleated metal strainers with a fold height corresponding to the mesh number of 400 cpsi, the thread thickness was 110 μm and the amount of substrate was 10 g / m ² . The bypass cell was a metal cell in the form of a direct channel with a mesh number of 400 cpsi, the foil thickness of which was 50 μm and the amount of substrate was 40 g / m ² . A preliminary calculation and iteration were carried out with respect to the sizes of the main cell and the bypass cell. The pressure loss for the annular bypass cell can be calculated based on the fact that the cell is round by adjusting the outer surface. The diameter of the main cell was set at 230 mm, as a result of which the use of 10.4 mm (70 mm round equivalent) of an annular bypass cell around the main cell first leads to a flow distribution in which 90.8% of the flow passes through the main cell and 9.2 % of the flow passes through the bypass cell (pressure loss 16.9 mbar). In the case where the entire flow should be directed in the other direction so as to pass through the bypass cell, the pressure loss will be 543 mbar, which, therefore, is the worst case. When the bypass cell size was smaller than the indicated value (<70 mm equivalent), the pressure loss in the case of the entire flow increased to an excessive value of 7366 mbar with the use of the bypass equivalent

- 14 031848 tape with a diameter of D30 mm, 1662 mbar when applying a bypass equivalent with a diameter of D50 mm. Even such structures (narrower channels) can probably be used as long as there is confidence that the main particle separator will never be completely clogged, so such an extreme worst-case scenario will never happen.

Example 2. Conditions, as in example 1, but the bypass cell used is an Ecocat ™ cell (50 μm foil, substrate 40 g / m ² ) containing tortuous channels. The outer surface of the bypass channel was maintained, as before (D70 mm), while the main flow was 90.3%, and 9.7% passed through the bypass cell (pressure loss 16.7 mbar). If the flow passes completely through the bypass cell, the pressure loss will be 501 mbar. If the amount of substrate in the bypass cell drops by 50%, i.e. up to 20 g / m ² , the flow distribution will be 89.3% / 10.7% (16.4 mbar and max. 424 mbar).

Example 3. Modeling particle accumulation under the assumption that their effect is similar to adding a substrate in Example 2. It is assumed that an open bypass cell does not capture particles at all. When the APE accumulated a 40 μm layer of particles, the flow distribution changed to 88.3% / 11.7% (21.9 mbar, max. 501 mbar). Accordingly, with a 100 μm solid phase layer, the flow distribution will be 85% / 15% (31.5 mbar, the maximum value remains the same, i.e. 501 mbar).

Example 4. The conditions for example 3 were also calculated for the direct channel bypass cell (400 cpsi, foil thickness 50 μm, the amount of substrate 40 g / m ² ). Based on the calculation, a correlation was obtained between the thickness of the particle layer relative to the size of the bypass channel,% and the pressure loss in the system (Fig. 10). When the entire flow passes through the bypass cell, the pressure loss is 543 mbar. The correlation obtained clearly indicates that the main flow, and thus the PM cleaning efficiency, remains on the side of the main particle separator up to layers of particles of medium thickness. The bypass channel is approximately 40% with a 500 μm layer of particles.

The corresponding method can be used for modeling and sizing from the point of view of pressure loss and flow distribution, as well as designs in which the main particle separator is a full-flow filter of the cell type and the bypass particle separator is, for example, an open type particle separator described in previous examples.

Bypass cell D70 is suitable for practical applications: 9.2% of the flow through the bypass cell, max. Δρ 543 mbar. Thus, the main part of the stream, i.e. approximately 80-91% of the flow will pass through the main cell, which has dimensions suitable for PM conversion of about 50 to 70%. When the clogging process begins, the back pressure across the bypass cell from the beginning to the end will be of the same order as the maximum Δρ value, often observed in DPF objects. In addition, the same principle can be applied when sizing for slightly different backpressures or flow distribution. In addition, when modeling and designing, it may be appropriate to consider a situation in which the back pressure of the bypass cell also increased slightly as a result of clogging.

Claims (10)

CLAIM 1. The apparatus for cleaning when processing fluids containing a solid phase, characterized in that it contains at least one main separator (3) of particles located in the middle part of the design of the apparatus for cleaning for the through flow (5) of the fluid, and at least one bypass particle separator (4) located around the main particle separator (3) parallel to it in the direction of flow, while the relative particle yield and pressure loss of the main particle separator (3) are higher than particle throughput and pressure loss of the bypass particle separator (4), while the bypass particle separator (4) is substantially less prone to clogging than the main particle separator (3), while the cleaning apparatus is arranged to process fluids by completely plugging the main particle separator (3), while it is possible to control the flow (5, 6) of fluid through the main particle separator (3) and the bypass particle separator (4) by means of relative backpressure in the main particle separator (3) and the bypass particle separator (4) in the absence of valves, and the main particle separator (3) or the bypass particle separator (4) is an open type particle separator consisting of at least two corrugated strainers, in which the fold of the strainer deviates from the direction of the main stream and the neighboring / superimposed strainers are located at mutually different angles relative to the direction of the main stream, while the height of the fold is selected based on the level of pure you are specified fluid. 2. The cleaning device (PUL) according to claim 1, characterized in that between the at least two pleated filters, there is one of the following groups: non-pleated - 15 031848 strainer, permeable wall, impermeable foil, wall for enclosing components in a shell in order to prevent them from mixing with each other. 3. The cleaning apparatus according to claim 1, characterized in that the ability to control the through flow (5, 6) of fluid between the separators, the main particle separator (3) and the bypass particle separator (4) is mainly provided by a fully static method based on relative back pressure , size and degree of filling of the separators without the use of control valves. 4. The cleaning apparatus according to claim 1 or 2, characterized in that if the main particle separator (3) is an open type particle separator, then the bypass particle separator (4) is a flow cell, and if the main particle separator (3) is a full-flow filter, such as a wall-flow filter, the bypass particle separator (4) is an open type particle separator that has permeable walls in the cell structure and open channels between these walls. 5. The cleaning apparatus according to any one of claims 1 to 4, characterized in that the main particle separator (3) is such that the through flow is more than 70%, preferably more than 85% in the unloaded state and / or during normal particle loads . 6. The cleaning apparatus according to any one of claims 1 to 5, characterized in that said cleaning apparatus is dimensioned such that when the entire flow passes through a bypass particle separator (4), an increase in pressure loss of 5-50 times is achieved, preferably 10-20 times compared to a particle-free cleaning apparatus. 7. The cleaning apparatus according to any one of claims 1 to 6, characterized in that the main particle separator (3) and the bypass particle separator (4) are coated with a catalyst configured to catalyze the oxidation of hydrocarbons, carbon monoxide, hydrogen, nitrogen oxides, ammonia and / or particles and / or reduction of nitrogen oxides with hydrocarbons, ammonia and the like reducing agents, and / or adsorption of nitrogen oxides. 8. The cleaning apparatus according to any one of claims 1 to 7, characterized in that the separation efficiency of the particles of the main particle separator (3) is from 50 to 100%, preferably from 60 to 99%, while the efficiency of the bypass particle separator (4) is from 20 to 90%, preferably from 30 to 70%. 9. The cleaning apparatus according to any one of claims 1 to 8, characterized in that the main particle separator (3) is a ceramic filter with a wall flow and the bypass particle separator (4) is an open type metal and / or ceramic particle separator. 10. The purification apparatus according to any one of claims 1 to 9, characterized in that an upstream purification catalyst (9) is additionally installed upstream of the collection device for purification, which plays an active role in the oxidation of hydrocarbons, carbon monoxide, nitrogen oxides and / or particles and / or catalytic removal of nitrogen oxides.