Negative Impacts of Free and Emulsified Water in Diesel

Diesel is one of the most widely used fuels in the automotive industry, power generation, and other sectors. However, the presence of free and emulsified water in diesel can have significant consequences on fuel performance, injection systems, engines, and emissions. Below, we explore the negative impacts of water contamination in diesel, as well as research conducted by companies specialized in this field.

According to a study by NORIA CORPORATE titled “The Four States of Water in Oil,” water is a destructive contaminant that affects both oil and the machines and systems it lubricates.

Historically, oil contaminated with water was understood to have two states: dissolved water (molecularly bonded with the oil) and free water (unbonded and separate). In the last 30 years, a third state has been recognized: emulsified water, which remains suspended in micro-droplets within the oil and does not separate easily due to the polarity and interaction between oil, water, and additives. These micro-droplets increase the turbidity and viscosity of the oil. Emulsification can occur due to colloidal condensation or mechanical agitation, which increases the contact surface between oil and water, trapping water inside the oil.

This emulsified water can negatively affect diesel engine performance, as water-emulsified fuels have a lower energy content than conventional No. 2 diesel. Customers should expect a power reduction of at least 15% and a 15% increase in fuel consumption when using fuels emulsified with water. Due to the lower energy content of these fuels, engines may require idle governor adjustments to prevent stalling—this is noted in one of CUMMINS’ technical bulletins.

In a fourth state, water can reverse its relationship with oil, becoming the continuous phase, with oil becoming the dispersed phase. This phenomenon occurs when water exceeds oil volume, such as in certain fire-resistant hydraulic fluids. Emulsified water in oil can be especially destructive due to its ability to cause both physical and chemical damage to oil and machinery. It is critical to detect and remove water promptly, as its presence can lead to long-term damage.

IMPACTS

Impacts on the
Fuel System

Impacts on
the Engine

Microorganism Growth

Impact on
Emissions

Impacts on the
Fuel System

The presence of water in diesel fuel can lead to the formation of sediments and the corrosion of tanks, pipelines, and fuel system components. This phenomenon can result in blockages, pressure loss, and damage to injection pumps, leading to costly repairs and equipment downtime.

Impacts on
the Engine

Water present in diesel fuel can have damaging effects on engines. Fuel lubricity may decrease, leading to increased wear of engine components. Additionally, the presence of water in the cylinders can cause damage to injection systems and irregular diesel combustion, resulting in power loss and reduced efficiency. All of this is caused by the chemical reaction between the sulfur in the fuel and the water, which leads to the formation of acids that not only cause internal engine corrosion but also degrade the lubricating oil.

Microorganism
Growth

Free and emulsified water in diesel creates a favorable environment for the growth of microorganisms, such as bacteria and fungi. These microorganisms can clog fuel filters, form biofilms on metal surfaces, and accelerate diesel degradation, ultimately affecting the fuel’s quality and stability.

Impact on
Emissions

The presence of water in diesel fuel can affect diesel engine emissions, contributing to incomplete combustion and undesired emissions. Microorganisms present in the fuel can also generate volatile organic compounds and acids that impact emission quality.

Studies Conducted by Industry Experts

  1. ExxonMobil Research and Engineering Company: ExxonMobil has conducted extensive research on the presence of water in diesel fuel and its impacts on fuel systems and engines. Their studies have provided detailed insights into the mechanisms of corrosion, sediment formation, and fuel degradation caused by water contamination.

  2. CUMMINS: Cummins reports that emulsified water can cause up to a 15% loss of engine power, which may also lead to a similar increase in fuel consumption.

  3. Bosch Automotive Diesel Systems*: Recognized as a leader in diesel injection systems, Bosch has conducted research on the influence of water on injection components and its effects on engine efficiency and emissions.

  4. Repsol Research and Development Center*: Repsol, a leading company in the fuels sector, has investigated the effects of water contamination in diesel on fuel stability and its implications for diesel engines.

  5. Chevron Fuel Research Lab*: Chevron has studied the formation of microorganisms in diesel fuel due to the presence of water, as well as their impact on filtration systems and engine performance.

Conclusion

In conclusion, the presence of free and emulsified water in diesel can have significant negative impacts on fuel systems, engines, and emissions. Research conducted by expert companies has revealed the complex mechanisms and consequences associated with water contamination in diesel, highlighting the importance of preventive measures and monitoring systems to ensure optimal diesel fuel quality and performance.

The use of coalescing filters is recommended when water contamination is severe or fuel consumption is high. For fuel usage up to 200,000 gallons per year, the use of water-absorbing solutions may be a viable alternative.

References

  • Free Water in Diesel Fuel: Challenges and Solutions, ExxonMobil Research and Engineering Company.
  • Influence of Water Contamination on Diesel Fuel Injection Systems, Bosch Automotive Diesel Systems.
  • Impact of Water Contamination on Diesel Fuel Stability, Repsol Research and Development Center.
  • Microbial Contamination in Diesel Fuel: Implications for Filtration and Engine Performance, Chevron Fuel Research Lab.

Negative Impacts of Contaminated Diesel

Negative Impacts of Diesel Contaminated

by Particles According to ISO 4406*

Diesel contaminated by particles represents a significant issue for any operation involving internal combustion engines. ISO 4406 sets standards for classifying particle contamination in oil-based fluids, but its relevance extends to diesel fuel, as the presence of particles can have negative impacts on:

  • Operational efficiency (Higher Fuel Consumption)

  • Energy efficiency and engine power

  • Service life of the injection system, engine, and lubricant

  • Environmental pollution

  • Health impacts on the community

IMPACTS

ON OPERATIONAL EFFICIENCY

ON ENGINE
LIFESPAN

ON THE
ENVIRONMENT

ON
HEALTH

IMPACTS ON
OPERATING EFFICIENCY

INCREASED FUEL CONSUMPTION

Contaminated diesel due to particles can have a direct impact on the operational efficiency of diesel engines. Particles present in the fuel can clog filters, injectors, and other components of the fuel system, resulting in decreased engine performance and increased fuel consumption. This clogging can lead to incomplete combustion, causing soot buildup and reduced engine power. Therefore, particle-contaminated diesel, according to ISO 4406 standards, can lead to a significant decrease in the operational efficiency of diesel vehicles, which in turn results in higher operating and maintenance costs.

THE 4 STEPS OF POWER LOSS

POOR
DOSING

POOR DOSING

Injection systems require ISO 11/8/7 diesel to optimally dose the fuel. Poor injector dosing due to the presence of particles results in power loss and consequently up to 5% higher fuel consumption.

LOSS OF COMPRESSION

LOSS OF COMPRESSION

Particles in the combustion chamber cause premature wear on the cylinders, leading to early compression loss—synonymous with power loss and increased fuel consumption throughout the engine’s service life, by up to 7%.

CONTAMINATED LUBRICANT

CONTAMINATED LUBRICANT

Particle-contaminated lubricant increases friction and temperature, causing up to 2–3% power loss and higher fuel consumption.

PREMATURE DPF SATURATION

PREMATURE DPF SATURATION

Pressure drop in diesel particulate filters (DPFs) causes up to 2% power loss and increased fuel consumption due to combusted particles.

IMPACTS ON
ENGINE LIFESPAN

The presence of particles in diesel fuel can also have direct consequences on engine performance. abrasive particles can cause accelerated wear on components such as cylinders, pistons, and rings, resulting in reduced engine lifespan and increased repair and replacement costs. additionally, particles in diesel can interfere with engine lubrication, leading to greater wear and damage to internal components, and even degrading lubricant additives—reducing oil change intervals. in summary, particle-contaminated diesel, as classified under iso 4406, can significantly decrease the performance and lifespan of diesel engines, affecting the reliability and durability of vehicles and machinery.

Impacts on the
Environment

In addition to impacts on operational efficiency and engine performance, particle-contaminated diesel also has significant environmental consequences. particles present in diesel can contribute to the release of pollutants into the atmosphere, affecting air quality and posing public health risks. incomplete combustion caused by the presence of particles can lead to increased emissions of exhaust gases, including nitrogen oxides (nox) and soot particles, both known for their harmful effects on human health and the environment. therefore, particle-contaminated diesel represents a serious environmental concern, and compliance with the iso 4406 standard is essential to minimize these impacts.

IMPACTS
ON HEALTH

Diesel contaminated with particles poses a serious threat to human health, as the microscopic particles present in this fuel can penetrate deep into the lungs when inhaled. The World Health Organization (WHO) reports that premature deaths caused by particulate matter emitted by engines reach 4.2 million annually. Chronic exposure to the particles found in contaminated diesel can lead to various respiratory issues such as chronic bronchitis, asthma, and even an increased risk of developing lung cancer. Additionally, these particles can travel through the bloodstream and affect other organs, contributing to cardiovascular diseases and nervous system complications.

The most vulnerable groups to these impacts include children, the elderly, and individuals with preexisting respiratory conditions. Therefore, it is crucial to implement strict diesel quality control measures to ensure compliance with the standards set by ISO 4406, in order to protect public health from the harmful effects associated with particle contamination.

COMPLIANCE WITH ISO 4406 STANDARD

The ISO 4406 standard establishes a method for classifying particle contamination in fluids, including diesel fuel. It defines the size and quantity of particles allowed in the fuel, providing a clear guideline to ensure the quality and cleanliness of diesel used in diesel engines. Compliance with this standard is essential to prevent the negative impacts of particle-contaminated diesel, as it sets clear benchmarks for fuel quality and contributes to engine protection, operational efficiency, and environmental preservation.

Recommendations and Conclusions

To mitigate the negative impacts of particle-contaminated diesel according to ISO 4406, careful attention must be given to the quality of the diesel fuel used in engines, along with the proper selection of ultrafiltration systems that meet high-efficiency standards such as THETA 4 > 4000 (in a single pass) and BETA 4 > 4000 (in recirculation). Additionally, when selecting filtration systems, it is essential to include filters that comply with SAE J1488 standards to effectively mitigate the presence of water in oil-based fluids.

It is recommended to perform regular diesel quality testing in accordance with ISO 4406 to ensure compliance with cleanliness and purity standards. Moreover, maintaining a preventive maintenance program—including the inspection and replacement of filters and fuel system components—is critical to avoiding particle contamination. The use of advanced fuel filtration and purification technologies can also play a significant role in preventing particle contamination and protecting diesel engines.

In conclusion, diesel contaminated by particles as defined by ISO 4406 represents a serious threat to operational efficiency, engine performance, and the environment. Adhering to the standards established by ISO 4406 is essential for minimizing these impacts and ensuring optimal performance of diesel engines. By adopting effective maintenance and quality control practices, it is possible to mitigate the negative impacts of contaminated diesel and promote reliable, sustainable performance in diesel engines across various industrial sectors.

OEMs have established ISO 18/16/13 as the MAXIMUM LIMIT and ISO 11/8/7 as the OPTIMAL standard, while in Latin America, the average diesel fuel consumed has a cleanliness level of ISO 22/20/17—between 1,000 and 2,000 times more contaminated than the established optimal level.