Since the introduction of the China 6 emission standard, most fuel vehicle brands have been equipped with particulate traps. Because the National 6 standard began to target the treatment of PM soot, while the first few emission standards were more for the conversion of carbon oxygen and hydrocarbons, it was more of a chemical conversion process. The use of particle traps to solve soot is more like a physical means.
Starting from July 1, 2023, China 6b+RDE will enter the stage of China 6b+RDE, which means that the third stage of China 6 emissions has now begun. Compared with the previous China 6A and China 6B (non-RDE stage), China 6B+RDE is more stringent. Therefore, the vast majority of car companies now use particle traps, and even Toyota, which has not been used before, has decisively compromised. As it stands, only Mazda models don't use particle traps, but that's only a matter of time.
What are the differences between the non-RDE phase and the RDE stage in China 6b?
China 6 emissions start with a buffer period, i.e., China 6a, then enter the China 6b non-RDE stage, and finally enter the China 6BRDE stage. So what are the differences between this RDE and non-RDE stages?The difference is reflected in the fact that in the non-RDE stage, car companies only need to report vehicle emission data, which means that they can use laboratory test data to report and meet the standards. After entering the China 6B RDE stage, the actual emission data of the vehicle driving on the road is assessed. The durability must reach 200,000 kilometers to be considered a standard.
The difference between the actual data and the laboratory data is very large, and the ideal working conditions can be simulated as much as possible in the laboratory, so that the emission data can be as ideal as possible. For example, in the laboratory, the test is carried out in ideal road conditions, and the vehicle is tested at as much constant speed as possible. The internal combustion engine operates stably at a constant speed and can maintain an ideal air-fuel ratio for a long time, so that the PM soot in the emission is easier to control. Therefore, in the non-RDE stage, European and American brands are the first to be equipped with particle traps, while Japanese cars are less equipped.
In the actual road conditions, there are too many uncontrollable working conditions, such as the road is very congested, and the car idles and creeps in place for a long time. At this time, the throttle valve is in a state close to full off, the combustion is very poor, and the carbon particulate matter increases a lot. On the other hand, in the process of continuous walking and stopping, each oil supply is a fuel enrichment process, that is to say, each oil supply is accompanied by an increase in carbon particles. As a result, actual emissions data is far more difficult to meet than laboratory data. So now even Toyota has begun to use particle traps, as shown in the picture above, the author made an estimate as early as last year for those who say that Toyota does not use particle traps, not no, the time has not come.
Why can't any car company escape the particle trap starting from the national 6 emissions?This is actually the same thing as the three-way catalytic converter becoming the standard, and all gasoline vehicles are equipped with a three-way catalytic converter starting from the China 2 emission standard. The three-way catalytic converter solves harmful gases such as HC, CO, and NOX, because these exhaust gases have been valued in the early years. With the continuous improvement and strictness of environmental protection requirements, PM soot emissions have become the primary problem. To solve the problem of soot, it can be processed from the source and the end, but it takes time to deal with the source.
The ideal way is to solve the problem at the source, and no one likes to have a particle trap on the rear of the car. It's just that the source treatment takes time and needs to be solved by optimizing combustion, and these technical upgrades need to consume a lot of money and time. Directly on the particle trap is simpler and more straightforward. From a certain point of view, the continuous upgrading of emission standards is constantly promoting the upgrading of automobile technology, such as the upgrade of fuel consumption standards, which has given birth to the generation of direct injection and hybrid technology. However, once the standard upgrade span is too large, then it will lead to the technical upgrade cannot keep up.
If the solution to the soot problem is put into the future China 7 emission standard, then all fuel vehicles may not need to be equipped with particulate traps. Nowadays, the implementation of this emission standard can only bite the bullet on the particle trap, which is the case for all car companies, and the supercharged models are the first to be equipped with and the naturally aspirated models can last for a few years. But even persistence is only a matter of time, and it is still the result of reducing the intensity of the spray. And this makes many cars have the problem of power loss, and the reason is simple147. The power and fuel consumption are the most balanced in the air-fuel ratio. But only in excess of air coefficient 0Concentrated fuel at 88 is the most powerful.
At this time, the air-fuel ratio is 129 or so, but at this time, the mixture is thicker, the combustion deteriorates, and there are naturally many carbon particles. The solution of some car companies is not to let the excess coefficient drop to 088, that is, the air-fuel ratio drops to 135 is the end, the mixture under this air-fuel ratio lacks explosive power. So some of today's models have almost no peak power, but the torque has dropped a bit. This is actually a last resort, and this is the case for models that use particle traps today, and the same is true for Mazda that does not use particle traps.
Some friends may wonder why the particle trap is so easy to block, and why is ternary not blocked?In fact, the three-way catalytic converter may be blocked even if it is permanent, but it is more difficult to block than the particle trap. The three-way catalytic converter also uses the honeycomb airway to capture the harmful components in the gas, but it captures the gas. Therefore, the radius of the ternary airway is larger than that of the particle trap, so the carbon particles in the exhaust gas will be discharged from the ternary (it will also form an attachment, and the tap water can be flushed). Whereas, particle traps are specifically designed to capture these carbon particles.
It's like the filter in the faucet at home, which has a blocked day in the morning and evening. Of course, it can be cleaned up, but there are some substances that cannot be cleaned up (adhesion, rust). The same is true for particle traps = a filter that continuously intercepts carbon particles, and when the intercepted carbon particles start to affect the operation, they burn at high temperatures. This is the process of converting solid carbon particles into carbon dioxide and carbon monoxide gas. Theoretically, it is possible to reuse the particle trap over and over again through regeneration technology, but in practice it is not only carbon particles that are attached to the particle trap.
There are also calcium oxide, phosphorus pentoxide, iron oxide, silicon compounds, etc., which cannot be removed by high-temperature incineration. So sooner or later there will be blockage, it's just the difference between early and late. Therefore, Toyota's particle trap is not blocked in large quantities this time, and Toyota will also experience what other car companies have experienced. All in all, in the new energy era, emission standards will only become more and more stringent, which can be seen as helping new energy vehicles open the way.