The Tier4 standard is a regulation developed by the Ministry of the Environment, which was published in 2021 and came into force after a 24-month adaptation period. Just as there are Euro standards from 1 to 6 for vehicles circulating on roads, there is a similar one, which is Tier, and its version 4 will be required in Chile starting in October for machinery engines, including agricultural machinery.
The objective of this standard is to reduce the emission of particulate matter (PM) and nitrogen oxides (NOx) through stricter limits. To comply with these limits, engines will have to incorporate elements or technologies that allow this. What is incorporated will depend on the brand, but it can be:
- Common Rail: Electronic control technology used in diesel engines that allows precise control of fuel dosing and high injection pressures. This system stores the fuel at high pressure in a common rail, from where it is distributed to the injectors of each cylinder, even at different times during the stroke.
- Exhaust Gas Recirculation (EGR): This system takes part of the exhaust gases and mixes them with fresh air. This means that the air entering the engine has less oxygen, which lowers the combustion temperature, reducing the formation of NOx. All of this is controlled electronically.
- DPF (Diesel Particulate Filter) system: It is a filter that captures combustion soot in the exhaust. If nothing is done, the system will become saturated, so it has to be regenerated in the following way:
- Passive: When the working regime is high, suitable temperatures are generated that burn this soot.
- Active: When a sensor detects that the filter is saturated, the engine control unit (ECU) sends a signal to carry out additional injections to raise the temperature and burn the soot.
- AdBlue: It is a liquid solution composed of urea (approximately 32%) and demineralized water (the remainder). This solution is injected into the exhaust system, before the catalyst, where it decomposes into ammonia (NH3) and carbon dioxide (CO2). Ammonia (NH3) reacts with NOx, generating harmless compounds such as nitrogen (N2) and water (H2O).
Points 1, 2 and 3 incorporate computers, sensors and systems to detect faults. This can be a problem in the field, since we do not know if we will have qualified labor in all sectors. Point 4 has complications such as crystallization due to weather, which can affect the sensors, providing erroneous data and obstructing the circuits through which it circulates. In addition, contamination of AdBlue, due to improper storage or adulteration, can be a problem. AdBlue is corrosive, so its poor handling can cause problems; there is also variation in price and availability of it.
The systems described may come in one, all or others that each manufacturer has developed.
In addition, the incorporation of each of these systems increases manufacturing costs and not all brand plants manufacture machinery with these elements, forcing them to look for more distant and higher standard factories, resulting in more expensive equipment, according to some, up to 40% more expensive.
Long Term Benefits
Despite the initial costs and technical challenges, the implementation of the Tier 4 standard will bring significant long-term benefits. The reduction of particulate matter (PM) and nitrogen oxides (NOx) emissions will improve air quality, which is crucial for public health and the environment. In addition, the use of advanced technologies can increase fuel efficiency and extend the life of machinery, resulting in long-term operational savings. The adoption of these regulations also positions the Chilean agricultural industry as a leader in sustainability and environmental responsibility.
