Find out what the permissible amount of diesel oil contamination is

Diesel oil is an essential fuel, used in large vehicles, industrial and agricultural machinery and in electric power generators. After its recommended period of use, diesel oil is partially deteriorated. This degradation results in the formation of oxygenated compounds, accumulation of wear metals, additives, in addition to other common contaminants, such as water, dust, among other substances.

Therefore, constant monitoring and maintenance is necessary to avoid contamination of diesel oil and the problems it causes. With proper control, we can reduce maintenance costs, increasing the useful life of the equipment. We will discuss in today’s post how to determine the permissible levels of metals and other substances responsible for the contamination of diesel oil.


Diesel oil contamination problems

Contamination of diesel oil is one of the main problems of this type of system, representing one of the most common failures in the industry. According to experts, the three most common sources of contaminants are water, suspended microparticles and the misuse of mixed fuel.

The presence of these substances brings several damages, as we can see in the list below:

  • It harms the combustion of diesel.
  • Accelerates filter saturation.
  • It can cause damage to the entire fuel system.
  • Speeds up the oil deterioration process.
  • Favors the development of bacterial colonies.
  • Causes early erosion of the parts.
  • Deregulate the engine.
  • Reduces power.
  • It requires higher consumption rates.

Therefore, performing effective monitoring and quality control of diesel oil is essential for maintaining the good condition and performance of the entire system. For this, it is very important to adopt evaluation parameters in order to determine the tolerable limits for metals and other oil contaminants.

Assessing diesel oil contamination

First, monitoring and following the trend of increasing the amount of metals and other contaminants is even more important than a measure in itself. Therefore, it is necessary to observe and compare with other results previously evaluated.

The values ​​may have as a parameter a diesel oil in a new state and still unused, but the manufacturers of the equipment and oil should also be consulted in order to determine exactly the ideal limits of each system. Through physical-chemical analyzes, it is possible to evaluate four different and important aspects: water, TAN, TBN and viscosity. All of these are more detailed below.

  • Water

Its presence in the oil prevents the action of additives and generates oxidation. Check below its tolerable limits and the respective recommendations:

– 150 ppm to 400 ppm: It is necessary to check the seals, vents and other possible entry points for contaminants, as well as paying close attention to the trend of future sampling.

– 400 ppm to 800 ppm: The source of water contamination must be checked and corrected urgently, in addition to adopting a program for efficient control and disposal.

– Greater than 800 ppm: Risks of serious damage to the equipment, requiring immediate intervention to eliminate water.

  • Viscosidade

This characteristic measures the resistance of the fluid flow. Here are your allowable limits:

– Viscosity variation greater than 10% in relation to new oil: It suggests the presence of an abnormality or more in the sample, requiring constant monitoring in order to determine its growth.

– Viscosity variation greater than 20% in relation to new oil: Risk of damage and serious imminent problems, requiring urgent intervention.

  • TAN

The TAN number indicates the amount of acids present in the diesel oil. If the quantity found is greater than that of new oil, oxidation and other types of contamination are likely to occur. If the results point to a number greater than 2, oxidation of the used oil is suggested.

  • TBN

This value is suitable for the alkalinity of oil, or its ability to neutralize acids. When your result indicates a 50% reduction in relation to the new oil reference value, you may have the presence of an abnormality or more, requiring a more attentive accompaniment.

Limits admissíveis de quantidade de metais

As seen above, aiming at the best possible interpretation of two results, it is necessary to analyze them over a long period of time, in order to assess their growth trend. The values ​​described below refer to some two main targets responsible for the contamination of diesel oil and its limits.

It is worth highlighting that these parameters are based on practical experiences; It is also necessary to consult the manufacturers of two oil equipment, seeking to determine the extent of the ideal limits of each system. Confira tabela to follow:

Aluminum (Al) 30 ppm
Lead (Pb) 100 ppm
Copper (Cu) 50 ppm
Chrome (Cr) 30 ppm
Iron (Fe) 200 ppm
Silicon (Si) 30 ppm
Take care of diesel oil contamination

All of these aspects and parameters point to the importance of constant assessment and monitoring methodologies for the good condition of equipment and systems. In this sense, the use of procedures such as filtering and microfiltration of Oil. These techniques work to control and eliminate contaminants, avoiding contamination of diesel oil.

Such methodologies can be adopted even in new oil, which may already be contaminated at the factory. Thus, you can identify and correct problems more quickly and assertively, reducing costs and the need for more frequent interventions.

You want to stay on top of everything aboutparticle count, filtration, microfiltration and how to choose the best procedure for your operation? Enter in contact with one of our experts or make a price.

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