Experienced motorists look at the particulate filter (DPF) as an absolutely unnecessary element. Its function is to reduce harmful emissions V environment. Drivers treat the component indulgently, as specifications It doesn't improve the engine. Passing through the filter, the exhaust gases encounter serious resistance, to overcome which the motor must spend a certain amount of power. This is just one of the reasons why drivers do not like soots.
What is a particulate filter on a car?
The DPF traps soot particles, which contain diesel engine exhaust gases. Since 2009, filters have become mandatory for use, before that they were used only on heavy trucks. They reduce the content of harmful substances in the exhaust by 90%. Soot settles on the walls of the component, which eventually leads to clogging - there is a need for cleaning (regeneration). The method of cleaning depends on the type of element. The following types of filters are common:
- with a catalytic coating (consists of a ceramic matrix with channels that filter the exhaust);
- with active recovery (contains an additive that is automatically injected into the fuel when electronic system determine the presence of contamination).
The additive of the self-cleaning element contains cerium, a chemical element that contributes to the destruction of soot deposits. Additive reserves must be replenished every 80,000 km. The additive is consumed faster if low-quality fuel is used.
Particulate filter: principle of operation and device
The size of soot particles is very small. They are 90% carbon, and it is almost impossible to retain them by conventional means, so diffusion is used in the filter device. The matrix consists of a network of tubes, the ends of which are closed on different sides. Soot comes from the engine side. Its particles cannot pass further - they penetrate into neighboring channels through the filter walls, after which they leave the matrix. During the passage from one channel to another, even very small particles are retained.
The Sazhevik looks quite simple, although its device can hardly be called such. It looks like a metal cylinder. To connect the cylinder to the cleaning system, pipes are located on both sides of it. Matrix inside the cylinder. Sazhevik also contains:
- pressure meter;
- temperature sensor.
Methods for installing a soot planter are different - it depends on the design of the component. Both matrices with a catalytic coating inside and conventional ones are used. In the second case, you have to put a catalyst on the engine.
Where is the particulate filter located?
particulate filter on a diesel it is in the exhaust pipe. Due to the design features, the part can be placed behind the exhaust manifold. The exhaust temperature there is at the maximum level, so the device has a special coating and is connected to the catalyst.
It can also be located between the muffler and the catalyst.
Types of particulate filters
For soot regeneration, two types of filters have been developed.
Soot with catalytic coating
The device is placed next to the motor. A high temperature must be created at the inlet. This element has a ceramic matrix, consisting of many small channels, which are arranged so that through one row the ends are either open or closed to receive exhaust gases. Porous walls create a filtering effect. Passing through them, soot settles, then undergoes oxidation by a catalyst.
Soot particles are a solid matter that gradually accumulates in the filter. Therefore, the filter must be cleaned periodically. Regeneration can be passive or active. At passive regeneration soot harmful substances upon contact with oxygen, they are converted into harmless carbon dioxide. Active regeneration - difficult process followed by two sensors.
Automatic planter
It is located for catalytic converter. The use of additives allows you to increase the exhaust temperature to a maximum, as a result, soot is neutralized. The sensors are triggered as soon as the filter is filled with soot deposits. The matrix is made of a material capable of for a long time withstand elevated temperatures.
Regeneration
During regeneration, the soot particles that clog the membrane are burned. The cleaning process itself involves increasing the temperature to such a level that the pollution occurs. There are 2 types of membranes - FAP and DPF. FAP is located farther from the motor. Here, the exhaust temperature is not high enough to strongly heat up the contaminants, so a special additive containing cerium is used. It heats the gas to a critical temperature, which contributes to the destruction of the blockage. Cerium is in the additive in the form of microgranules.First, under the influence of gases, the shells of the granules evaporate, then cerium is released. Then, when it hits the membrane, ignition occurs, and the temperature of the gases rises greatly. Warming up is local, so it is safe for the system. Of course, the ceramic grating is gradually destroyed, but this process is very long.
DPF are located close to the motor. Therefore, no additional devices are required to maximize the heating of the gas. Hot gases immediately enter the filter, burning off the soot. Such a procedure can only be carried out when driving at full speed, so the car sometimes needs to be accelerated to the maximum.
It is not necessary to carry out the regeneration procedure every day - start from the intensity of the formation of soot deposits.
A clogged soot can not be used, because over time it will destroy the engine. Service centers have equipment that starts the process of forced regeneration. But this will not work if the filter is clogged beyond the norm. Here it is already necessary to flush with special means, which will remove the bulk of the deposits. Flushing can be done in one of 2 ways:
- partial flushing (element is not removed);
- deep flushing (implying the removal of the element).
Partial flushing is carried out with a spray gun, a tube and a special agent. You will also need a compressor that will create required pressure. We remove the temperature sensor, open access to the filter and clean it. One procedure takes up to a liter of cleaning fluid, which is usually used as NUNAP MP 131. Then we return the sensor to its place.
When deep flushing, remove the element completely, rinse it special tool- for example, DPF Cleaner. The active liquid neutralizes soot deposits, and they are easily removed by water supplied under pressure. Cleaning is more effective if it is carried out with a compressor. After cleaning, dry the filter element, then put it in place.
Flushing does not always completely destroy the blockage. If this fails, it is better to buy and install a new element.
Washing agents contain substances harmful to the skin, so the procedure should only be carried out with protective gloves.
Removing the particulate filter: consequences
Replacing the filter element is an expensive procedure, so some prefer to simply remove the component. What may be Negative consequences, few people stop. According to the rules, before removing the element, you need to reflash the control unit - otherwise the emergency mode will “burn”.
The flashing procedure is best done in service centers is a very responsible job. Here's what the driver wins:
- The resistance to the release of gases will be eliminated, so the motor power will increase.
- No need to constantly spend money on new filters.
- Fuel consumption will be reduced.
After removing the filter element, you can forget about driving your car to Europe - the car warranty is void. Turbine speed can increase to such a state that their whistle will be heard. At high speed, pieces of soot will fly out of the exhaust pipe - this can be observed with the naked eye. Emission indicators will also worsen due to the fact that the catalyst will have to be cut out, and illiterate flashing may well lead to burnout exhaust system.
The soot filtration system is designed to improve environmental performance. Most likely, someday for the lack of such a system in the car will be fined. So why delete it? The car will go a little faster, but there are so many negative consequences that it is clearly not worth it.
Diesel engines were invented a long time ago, but the technology continues to develop to this day. One of the latest innovations was the use of a particulate filter. Since the early 2000s, Volvo, BMW and Mercedes have been actively using it in new models. After the Euro-5 standard was adopted in the European Union, the particulate filter has become an invariable component of diesel engines.
What is a diesel particulate filter for?
The diesel particulate filter has several abbreviations. For example, in a Ford Kuga car, it will be designated DPF, in Volkswagen, Audi and Opel Astra 2.2 cars - RPF, and in Renault Megan 3 or Renault Laguna 3 - FAP. All these are abbreviations from English, French and German language. So don't be surprised if dashboard one of these symbols will appear. So the filter needs service.
This little gadget is of great importance for the environment, as it helps to reduce the amount of emissions into the environment. Engines without a particulate filter emit 99% more waste into the air.
Diesel engines, unlike gasoline analogues combustibles are not completely burned, as a result, soot is formed. Soot microparticles ranging in size from 0.1 micron to 1 micron, they include water vapor, sulfur, carbon compounds and heavy metals. A more specific composition depends on the quality of the diesel and the type of engine. If this deposit is not cleaned in time, the filter will have to be replaced with a new one. The price for it is quite “biting”: from 900 to 3000 euros, depending on the brand of the car.
Where is the particulate filter
The particulate filter is located in the exhaust pipe. In some vehicles, it may be located behind the catalytic convector or combined with it. In this case, the filter is located behind the outlet distributor. At this point, the heat of the exhaust gases reaches its maximum.
Diesel particulate filter video
What does a particulate filter look like
The most important part of the particulate filter is a ceramic matrix, it is made from carborundum. In order for the matrix to be conveniently fixed, it is placed in a metal base. If we take a closer look at the ceramic matrix, it will be seen that it consists of cells of small cross section, which are alternately closed on both sides. The design also includes end walls with a spongy structure, which act as an additional filter.
In the first versions of the matrix, the cells had rectangular shape. Now manufacturers are gradually switching to octagonal, as it is more practical. The fact is that this form gives an advantage: it becomes possible to place large quantity cells and extend the life of the filter.
The principle of operation of the particulate filter
Passing through the particulate filter, soot goes through two main stages: filtering and cleaning. During the first, soot microparticles pass through the filter and settle on its walls. The most difficult in this process is the capture of microscopic particles up to 1 micron in size. They account for only 5% of total mass exhaust gases, but they are the most undesirable for the human body. Good innovative technologies make it possible to retain even such microparticles.
The microparticles that accumulate during filtration form soot, which prevents the exhaust gases from escaping. As a result, engine thrust is lost. Therefore, the filter needs regular cleaning. There are two ways to clean these days: calm and proactive. New filters usually use both technologies.
The quiet method occurs due to the design features of the exhaust pipe. As already mentioned, the particulate filter is located in the place where the heat from gases is the strongest (it can reach 1000 ° C). Or when using special additives that are injected into the fuel. They are able to provide soot oxidation at 450-550 °C.
Such additives are necessary for light engine loads, for example, when driving in city driving conditions. Then the motor is not able to generate sufficient temperature to burn unwanted soot. In these cases, forced quiet regeneration is used.
Intensive cleaning is a little more difficult, since it needs additional steps, after which the temperature rises to 600-700 ° C. There are several ways to do this:
- delayed fuel injection
- Additional fuel injection during intake
- Application of an electric heater before the filter
- Fuel injection in front of the particulate filter
- Heating gases with microwaves
- Designers are trying to facilitate the regeneration process, so modern filters are increasingly equipped with a tank with a fuel additive.
Diesel particulate filter with catalytic converter
A number of manufacturers use for some car models (Santa Fe, Tuareg 3.0, Nissan X Trail) a particulate filter with a cataloger, which is able to provide both active and passive filter cleaning.
The operation of this system is provided by a plate with a catalyst. At the same time, a calm and intensive cleaning takes place.
Peaceful cleaning occurs continuously. The coating allows the soot to be oxidized. As a result, it burns to form carbon monoxide and carbon dioxide. The process is carried out at 300-400 °C.
Intensive cleaning occurs due to the injection of heat gases (over 600 ° C) by the diesel control mechanism. It is possible to determine when the filter needs active cleaning using special sensors. These include: an air flow meter, an exhaust gas thermometer and a pressure gauge.
When the sensors signal that it is time to clean the filter, the computer activates the intensive cleaning process. First, fuel injection inside the combustion chamber is increased. Secondly, the valve is closed, which is responsible for the amount of oxygen supply to the motor. It also turns off the exhaust recirculation process. All this makes it possible to create the necessary conditions for intensive cleaning.
Diesel particulate filter with reservoir for fuel additives
Another popular way to clean the particulate filter is to install an additional additive injection mechanism into fuel system. Such filters are also called FAP filters, since they were first proposed by French designers. The technology was later adopted by car manufacturers Ford and Toyota.
To implement the idea, the designers used a special additive - cerium. It is able to ensure the oxidation of soot even at a low temperature of 400 °C. But engines that are not exposed heavy loads, are not able to provide the required temperature, so active cleaning is carried out in parallel. When using a diesel particulate filter with additive injection, the filter is usually installed separately from the catalytic converter.
The additive is located in a special tank inside or outside the fuel tank. At each refueling, an additive is added to the fuel. One tank is enough for about 100-110 thousand km. run. The filter itself serves about the same amount. The downside of using the additive is that during its combustion, ash is deposited on the filter walls, creating additional problems.
Diesel particulate filter replacement
When the filter is completely clogged, it will have to be removed physically and programmatically. That is, you will have to additionally change the computer program, otherwise it will give an error.
If desired, a new particulate filter can be omitted. In Russia, there is no penalty for its absence. At the same time, engine thrust will improve, fuel consumption will decrease and it will be possible to fill in ash oil. However, in Europe, for such a ride, a fine shines, almost equivalent to the cost of replacing the filter.
How to extend the life of the particulate filter
After the end of the cycle of using the particulate filter, it is not so easy to buy a new one, it costs a lot. Therefore, it is important to extend the life of your own during operation. To do this, you need to clean it in a timely manner and choose the right engine oil.
Ash, low-ash and ultra-low-ash types are now produced. engine oil. Ash from the oil settles on the surface of the combustion chamber, and then collects inside the particulate filter. This means that the ash content of the oil has a direct effect on the life of the filter. So good oil and timely service can help extend the life of the particulate filter by several tens of thousands of kilometers.
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In every diesel car there is a particulate filter. If it is not cleaned, this will lead to serious consequences for the machine.
Its clogging leads to the ingress of particles into the environment, so that it is harmful to humans, and on the machine this affects problems with the electronics signal on the dashboard, a decrease in traction and dynamic characteristics, interruptions in the operation of the motor, and an increase in oil level.
That is why diesel particulate filter cleaning is carried out.
What is this?
The diesel particulate filter (DPF) is a part used in the design of such engines to purify exhaust gases from unwanted impurities.
It reduces the amount of emissions into the environment by accumulating harmful substances and soot. But since it is the ultimate reservoir for their accumulation, it must be cleaned periodically in order to regenerate the DPF.
This process burns off excess soot deposited in the filter, reducing emissions and helping to prevent black smoke.
Causes
If the DPF becomes clogged with soot or an error occurs in the system, an orange light will usually appear on the dashboard.
Short trips to low speeds are the main cause of blocked filters.
That's why automakers often recommend choosing a car that runs on diesel rather than diesel (and why diesels are rare in the urban automotive sector).
The filter is able to clean itself only when driving on high revs, and if the driver drives only within the city, this becomes impossible. Any master at the service station will tell you that cleaning should be done every 150 km.
Oil can also cause contamination. Some of them contain additives that can actually block diesel particulate filters.
All this can lead to damage to the diesel particulate filter, as well as when using low-quality fuel and even when driving the car often on low fuel levels, as the car can avoid DPF regeneration to save fuel.
Cleaning methods
There are several ways to remove soot from a DPF. It is passive and active regeneration or the use of special tools.
Passive regeneration
Particulate filter? Passive regeneration occurs when the vehicle is driving high speed along the motorway. This makes it possible to raise the exhaust temperature to more high level and burn off excess soot in the filter.
However, not all drivers do this regularly - which is why manufacturers have developed an alternative form of regeneration.
Active regeneration
This method means that additional fuel is injected automatically as part of car ECU when the filter reaches a predetermined limit (usually around 45%) to raise the exhaust temperature and burn off the accumulated soot.
Problems can arise if the journey is too short, as the regeneration process may not complete completely.
If so, the warning light will continue to indicate that the device is still partially contaminated.
You will know if active regeneration is taking place, because it will be manifested by such signs:
- pungent smell of exhaust gases;
- increased idle speed;
- cooling fans not working;
- slight increase in fuel consumption.
Cleaning the device is not a problem, the main thing is to know how to do it correctly.
Does not cause the indicated problems. The motor engine runs without interruption, and there will be no other problems either.
Liquids
What to do if neither active nor passive regeneration works?
If the warning light continues to flash, cleaning is not successful. It is required to replace the part or remove it for washing with professional products.
Do not fill diesel oil until flush cleaning fluid has been used.
How to clean diesel particulate filters?
It must first be dismantled and then used special liquids. But thanks to these funds, you can do without removing it, because this is the most difficult: PRO-TEC, Luffe, Liqui Moly.
They reduce the formation of soot during fuel combustion. Cleans and regenerates blocked soot filters without dismantling.
The fuel system of a car is very sensitive to contamination. This contamination can increase engine noise, fuel consumption and reduce engine lubrication and power.
Use of fuel flushing agents on a regular basis will help keep the fuel system clean and the engine will run more efficiently, reducing fuel consumption and reducing harmful emissions.
Particulate filters are better to clean than to run and then change to new part. They are expensive. Carry out regeneration in accordance with the requirements and this problem will not affect you.
Since 2000, passenger cars with a diesel engine have been using a diesel particulate filter as part of the exhaust system. With the introduction of Euro 5 standards in January 2011, the use of a particulate filter on passenger cars with a diesel engine is mandatory.
Diesel particulate filter (in English version Diesel Particulate Filter, DPF, in the French version Filtre a Particules, FAP, in the German version RubPartikelFilter, RPF) is designed to reduce the emission of soot particles into the atmosphere with exhaust gases. The use of a filter makes it possible to reduce soot particles in exhaust gases by up to 99.9%.
In a diesel engine, soot is formed when fuel is not burned completely. Soot particles have a size of 10 nm to 1 µm. Each particle consists of a carbon core, to which hydrocarbons, metal oxides, sulfur and water are connected. The specific composition of soot is determined by the mode of operation of the engine and the composition of the fuel.
In the exhaust system, the particulate filter is located behind the catalytic converter. In some designs, the diesel particulate filter is combined with an oxidation-type catalytic converter and is located immediately after the exhaust manifold where the temperature of the exhaust gases is maximum. It's called a catalytic coated particulate filter.
Main constructive element The particulate filter is a matrix that is made of ceramic (silicon carbide). The matrix is placed in a metal case. The ceramic matrix has a cellular structure consisting of channels of small cross section, alternately closed on one side and the other. The side walls of the channels have a porous structure and play the role of a filter.
In cross section, the cells of the matrix have a square shape. More perfect are the input cells of the octagonal shape. They have a larger surface area (compared to exit cells), allow more exhaust gases to pass through and provide longer term particulate filter service.
In the work of the particulate filter, two successive stages are distinguished: filtration and regeneration of soot. During filtration, soot particles are captured and deposited on the filter walls. Small soot particles (from 0.1 to 1 µm) are the most difficult to capture. Their share is small (up to 5%), but these are the most dangerous emissions for humans. Modern particulate filters retain these particles as well.
Soot particles accumulated during filtration create an obstacle for exhaust gases, which leads to a decrease in engine power. Therefore, periodically cleaning of the filter from accumulated soot or regeneration is required. A distinction is made between passive and active regeneration of the particulate filter. IN modern filters As a rule, passive and active regeneration are used.
Passive particulate filter regeneration carried out at the expense high temperature exhaust gases (about 600 ° C), which is achieved when the engine is running with maximum load. Another way of passive regeneration is the addition of special additives to the fuel, which ensure the combustion of soot at a lower temperature (450-500°C).
Under certain engine operating conditions (light load, urban driving, etc.), the exhaust gas temperature is not high enough and passive regeneration cannot occur. In this case, active (forced) regeneration of the particulate filter is carried out.
Active particulate filter regeneration It is carried out by forcibly raising the temperature of the exhaust gases for a certain period of time. The accumulated soot is oxidized (burns out). There are several ways to increase the temperature of the exhaust gases during active regeneration:
- late fuel injection;
- additional fuel injection on the exhaust stroke;
- usage electric heater before the particulate filter;
- injection of a portion of fuel directly in front of the particulate filter;
- heating of exhaust gases by microwaves.
The design of the particulate filter and the systems that ensure its operation are constantly being improved. Currently, the most popular particulate filter with a catalytic coating and particulate filter with a system for introducing additives into the fuel.
Particulate filter with catalytic coating
Diesel particulate filter with catalytic coating applied to automobiles Volkswagen Group and a number of other manufacturers. In the operation of a catalytic coated particulate filter, a distinction is made between active and passive regeneration.
During passive regeneration, soot is continuously oxidized due to the action of the catalyst (platinum) and the high temperature of the exhaust gases (350-500°C). The chain of chemical transformations during passive regeneration is as follows:
- nitrogen oxides react with oxygen in the presence of a catalyst to form nitrogen dioxide;
- nitrogen dioxide reacts with soot particles (carbon) to form nitric oxide and carbon monoxide;
- nitric oxide and carbon monoxide react with oxygen to form nitrogen dioxide and carbon dioxide.
Active regeneration occurs at a temperature of 600-650°C, which is created using the diesel control system. The need for active regeneration is determined based on an assessment bandwidth particulate filter, which is carried out using the following sensors of the diesel control system: air flow meter; exhaust gas temperature before the particulate filter; exhaust gas temperature after the particulate filter; pressure drop across the particulate filter.
Based on the electrical signals of the sensors the electronic unit control system produces additional fuel injection into the combustion chamber, and also reduces the air supply to the engine and stops exhaust gas recirculation. In this case, the temperature of the exhaust gases rises to the value required for recirculation.
Diesel particulate filter with fuel additive system
A diesel particulate filter with a system for introducing additives into the fuel is a development PSA concern(Peuqeot-Citroen). Since the pioneers in the use of additives for regeneration are the French, the name FAP filter (from the French Filtre a Particules) has stuck to the filter. A similar approach is implemented in particulate filters from other automakers (Ford, Toyota).
The system uses an additive containing cerium, which is added to the fuel and ensures the combustion of soot at a lower temperature (450-500°C). But even this exhaust gas temperature cannot always be reached, so the system periodically performs active regeneration of the particulate filter. The diesel particulate filter is usually installed separately after the catalytic converter.
The additive is stored in a separate tank with a capacity of 3-5 liters, which is enough for 80-120 thousand kilometers (filter service life). Structurally, the tank can be located in the fuel tank or outside it. The additive level in the tank is controlled by a float-type sensor. The additive is supplied to the fuel tank by means of electric pump. Additive supply is carried out at each refueling fuel tank proportional to the amount of fuel supplied. The start and duration of the additive supply is regulated by the engine control unit (in some designs, a separate electronic unit).
A side effect of using the additive is that during combustion it settles in the form of ash on the filter walls and is not removed from it, which reduces the life of the device. The service life of a modern diesel particulate filter is 120,000 km. Manufacturers declare release in soon filter with a resource of 250,000 km.
Due to the high cost of exhausted particulate filters, car owners, as a rule, are not replaced, but removed, followed by a flashing of the engine management system.
An article about the particulate filter - what it is for, features and operation of the part. At the end of the article - a video about the device and the purpose of the particulate filter.
The content of the article:
Diesel equipment cars received since 2000 an additional part in the exhaust system - a particulate filter. The filter element is expected to reduce high performance emission of heavy particles and CO2 into the atmosphere.
According to the status of the Euro-5 standard, the installation of a filter unit on a car is mandatory. The unit really reduces the emission of soot into the environment by 90%, but at the same time it requires a full cleaning after a maximum of 20-30 thousand mileage.
Given that diesel fuel Russian production contains five times more sulfur than European diesel fuel, a cleaning procedure or complete replacement drivers are forced to make filters every 10,000 runs.
The classic purpose of the part
particulate filter for diesel engine reduces the emission of fine soot particles by filtering exhaust gases. Carbon deposits are formed when fuel is not burned properly. Chemical composition soot depends on the parameters of the fuel, most often it is heavy particles, hydrocarbon dioxide and oxide, sulfur dioxide, water, nitrogen oxide, in different proportions.
At the heart of the part is a ceramic ingot of a cellular shape, enclosed in a welded metal casing. An exhaust gas purification unit is installed immediately after the catalyst, making up a single part with it. The filter and neutralizer are located in the same bank, directly after the outlet manifold. In some models, an oxidation-type auto catalyst and a filtration element are combined into one unit. Technologically, the part is called a catalytic type filter.
The original part is quite expensive due to precious metal, which is part of the filter structure. Iridium and platinum neutralize exhaust emissions and trap soot particles.
The particulate filter cells are either square or octagonal in shape. Closed since different sides, they create a complex passage for the exhaust gas, due to which new filter according to measurements, it releases almost clean air under high pressure into the atmosphere.
The unit performs two functions during operation:
- spent fuel filtration;
- soot regeneration.
Restoration of the filter assembly
Filtering units latest generation(since 2010) have two types of soot recovery - automatic (passive) and forced (active).
IN modern foreign cars more often used passive system, burning soot using exhaust (from 500 degrees). It happens on high speeds without additional command from the ECU.
Passive regeneration method is that the manufacturer came up with the idea of adding a special additive to diesel fuel. This method is acceptable if the car is not often used for country trips. Mode of operation in the city with frequent stops most detrimental to diesel trim levels.
Active recovery involves forced temperature build-up in the node for complete oxidation (combustion) of plaque. Depending on the parameters of the engine, there are several ways of forced regeneration:
- Late fuel supply.
- When the gases are released, an additional injection occurs.
- Electrical heating
- Using microwaves to heat spent fuel.
Volkswagen engineers most often install a particulate cleaner with a catalytic shell (coating) on their models. The exception is the Transporter minibus models, which are the first in line at the car service to remove this unit. After a run of 30,000, no regeneration of the unit, cleaning, flushing, etc., help these cars. Analogues fail after 5,000 km.
The catalytic coated particulate assembly is installed immediately after the turbine compressor and constitutes one unit with a catalytic converter in a common housing. When replacing or changing to a flame arrester, both parts are knocked out. The unit is based on a ceramic porous jar, the cell walls of which are coated with a layer of platinum, iridium, cerium oxide and aluminum.
The catalytic material coated filter assembly can be passively and actively regenerated. Passive recovery occurs every minute during engine operation at high speeds due to the exhaust temperature (at least 500 degrees).
Active recovery is carried out through additional heating of the soot unit, either with additional injection at different cycles, or with the connection of additional units. Active cleaning occurs within 10 minutes after the ECU has processed the data from the exhaust system sensors. The indicators are based on:
- air flow;
- gas temperature before and after the filter unit;
- parameters of the pressure drop in the catalyst.
The developers of the design of the exhaust gas purifier is the Peugeot-Citroen concern. As a basis, the engineers took a cerium additive, which ensures the combustion of soot at medium temperatures (from 450 degrees). This design is installed after the catalyst and is a separate unit.
A fuel additive with a volume of up to five liters is located in a separate container, which is either built into the fuel tank or placed in engine compartment. A volume of 5 liters is enough for a run of 150,000 - 180,000 km. Measuring the additive level is similar to checking the level brake fluid, based on a float with a scale. The addition of the additive occurs while filling the fuel tank proportionally.
The particulate filter, like the catalyst, is certainly a necessary unit in a car, but since there are enough problems with maintenance, replacing the unit, drivers prefer to remove the regular unit after the resource is exhausted. At the same time, it is worth remembering that removing the catalyst and filter, as well as replacing it with a flame arrester, is an administratively punishable action. To risk or not is an individual choice.
Video about the device and the purpose of the particulate filter:
