Diesel engines require clean diesel, free of water and contamination. While old generation engines were tolerant to bad fuel, fuel injection systems on new generation engines are extremely sensitive to fuel quality. Water contamination must be fully removed and diesel shall be protected from degradation for sustainable engine performance, emission compliance and long life of aggregates.
Conventional spin-on type filtration systems supplied with OEs are designed to work efficiently on diesel complying with ASTM standard. In most
This difference in performance of filtration systems is known to all in the industry. Had standard filtration systems worked efficiently in the field, there would be no fuel related operational problems. But in reality this is not the case. Greater understanding of the problem affecting fuel quality is essential for appreciating the solution.
Incomplete combustion leads to fuel wastage
When the combustion is not complete, diesel wastage is increased, meaning more fuel is burned or consumed for generating the required power. This is a universal problem, for which the only solution is for the customer to become pro active. Educating the customer on the problems of filtration and protection of diesel is an absolute must if they should get the desired and rated performance from their engines.
Getting to know the problem
Engine makers and fuel suppliers will not take the responsibility on operational problems arising from poor quality fuel. Fuel suppliers’ responsibility ends when the fuel is sold to the customer.
But the problem of contamination is something, which takes place in the tank. Engine makers are clear on their stand when they test and publish their engine’s performance data based on good quality fuel meeting with the standard.
This means, if the engine performance is not as per the makers recommended levels and premature component failures occur owing to poor quality fuel, engine makers will not own up the responsibility in normal cases.
This leaves the customer and the service personnel in a difficult situation leading to protracted claims, arguments and sometimes customers shying away from trusted brands assuming that the failures are caused by poor workmanship and materials of components used. It is with this reality in mind that we should approach the problem and look for a Filter Element of Engine not protected with Ecotech Fuelmag reliable solution.
The Problem – major factors affecting diesel quality–
1. Adulteration
2. Dissolved and free water
3. Suspended particulates, and
4. Bio degradation
Since conventional filters render inadequate to deal with all the problems affecting diesel quality, need for a reliable pre filtration and conditioning system assumes significance.
Dealing with the problem
1. Manmade adulteration could be dealt with enactment of law
2. Water could be totally removed with a high efficiency water separator
3. Particulates could be filtered using appropriate fine filters provided by engine makers.
4. Bio degradation is a natural phenomenon caused by numerous microbes thriving in diesel tank using the carbon molecules of diesel for its survival and proliferation. Conventional filtration technique will not prevent microbial activity in diesel. Hence a different approach to solution is required.
Microbial contamination and bio degradation of diesel
Bio degradation of diesel is a natural phenomenon taking place in diesel tanks, which we do not see. Diesel tanks, through its breather, always draw moisture laden air and airborne microbes into the diesel. With the presence of moisture and free water in diesel, these microbes multiply in diesel tank using the carbon molecules of diesel as its food.
Temperate climatic condition prevailing in India acts as a catalyst to this process, technically referred to as bio degradation. When diesel is degraded biologically by microbes, it becomes unfit for the engine’s consumption or we say, the diesel becomes off spec.
When the diesel is contaminated with bio degradation, the quality and chemical characteristics of diesel is altered.
Diesel becomes more acidic as a result of microbes oxidising the carbon molecules for its food requirements. This oxidation process introduces acidic substances in diesel including bio surfactants.
Bio surfactants helps diesel to emulsify with water and carries the water to engine through fuel pump and injectors.
Water molecules entrapped in diesel becomes highly abrasive under high pressure created by fuel pumps and cause erosion to fuel pump and injector components. Bio degradation will also reduce the natural lubricity of diesel. As you are aware, modern fuel pumps use diesel for lubricating its internal components built to very tight tolerance. This reduced lubricity of diesel is a major cause of fuel injection pump and injector failures.
However owing to operational requirements, cost considerations and lack of awareness of bio degradation, many customers do not have the resources for testing the quality of diesel periodically.
As a result, contamination and bio degradation process remains unchecked causing several operational problems to engine and eventually affects fleet reliability and profitability.
Adverse effects of microbial activity in diesel
- Oxidation of fuel
By products such as corrosive acids andbio surfactants
- Diesel water emulsification.
Oxidation promotes formation of Asphaltene (large lumps of black sticky substance) causes filter clogging. Black slimy filter media is an indication of oxidation of fuel.
Bio surfactants help diesel and water to emulsify. Filters present in engine’s fuel lines will not separate/remove water from diesel water emulsion. Water and corrosive acids reduces diesel’s natural lubricity causing premature wear and tear of fuel injection pump and injectors.
Water, owing to its surface tension and specific gravity difference displaces diesel from wear components and accelerate wear and tear of precision components of fuel injection system.
Degradation leads to contamination and reduced calorific value. Diesel affected with microbial activity will be cloudy and at times discolored.
Operational problems
- Filter clogging causing fuel restriction and reduced filter life.
- Inadequate filtration due to filter channeling
- Accelerated wear and tear of fuel injection system
- Injector sticking, injector tip burn out
- Corrosion in fuel system, tank and engine
- Sludge deposit in fuel tank and corrosion of tank caused by Sulphate
- Reducing Bacteria (SRB)
- Incomplete combustion resulting in increased fuel consumption and smoke.
Control measures to deal with microbial contamination and degradation
1. Enhanced house keeping
2. Frequent testing of diesel from storage tanks and engine’s tanks
3. Treating diesel with biocides
4. On line protection
Analysis of control measures
- Housekeeping shall involve plugging all loopholes in fuel supply chain such as deficiencies in fuel transportation, storage, delivery and engine’s tank. This requires a holistic approach involving all stages of fuel handling right from fuel supplier till it reaches engine’s tank and beyond. Storage tanks, wagons and tankers carrying diesel fuel, filling lines, and engine’s tank must be steam and chemical cleaned periodically to remove all sludge, sediments and free water.
Though this will minimise the incidence, it requires high investment in terms of equipment and personnel and therefore not an assured way to deal with the problem.
2 Testing diesel frequently for presence of microbes.
3. Treating affected diesel in the tank involves precise dosage of biocides.
Once treated the entire volume of diesel should be filtered to remove all slime and sediments.
Biocide treated diesel should not be mixed with other batches of diesel as it would dilute the strength of biocide and aggravate the problem Since there are practical difficulties associated with this procedure, it is not a viable solution
4. Online protection – Flow through diesel conditioner installed in the diesel suction line after the tank and before existing primary filters and fuel transfer pump. This system ensures continuous cleaning and conditioning of diesel by destroying microbial colonies. Since it is installed in the fuel suction line, it cleans and protects the entire diesel volume in the tank making use return fuel flow from Fuel pump and injectors.
This is a permanent system with no recurring expenses and intervention with a service life expectancy in excess of 20 years.
Online diesel decontaminating system
Ecotech Fuelmag diesel decontaminating unit is a flow through diesel conditioner.
As the fuel passes through the unit, the microbial colonies get severely disrupted and broken down to original plasmolised cell size of less than a micron.
These cells pass through the fuel filter and burn up in the combustion chamber. The fuel returning to the tank will contain bacteria but will be in dormant state unable to multiply. This continuous process will keep the diesel from getting contaminated and degraded.
Since microbial activity is totally controlled in the fuel system itself, the risk of contamination and by products is totally eliminated.
Benefits of Ecotech Fuelmag
- Extended fuel stability
- Clears microbial slimes and protects diesel
- Prevents diesel water emulsification
- Prevents diesel degradation
- Enhances fuel filtration and water separation
- Extends primary and secondary fuel filter life
- Extends fuel pump and injector life
- Unrestricted fuel flow
- Helps total combustion and optimum utilization of fuel, and
- Reduces smoke and engine vibration
Water contamination
Water in diesel is referred to as “water bomb”. The damage water could cause to fuel injection systems and engine is well known to the industry. Even a tiny water droplet is sufficient to cause injector damage if it reached the combustion zone. Though water separators are available dime a dozen, for total water removal a high efficiency water separator is absolutely necessary. Most common water separators are either gravity type, spin on type with a water absorbing media. The spin on types have an efficiency of about 95%. This means, 5% of water could still find its way to FIP and engine causing operational problems.
Water being heavier and also owing to its surface tension difference, displaces diesel from wear components of FIP and injectors, promoting accelerated wear, and cavitation damages, greatly reducing the effective service life of FIP and injectors. The cumulative losses from premature wear and tear is a critical issue many operators face today with rotary pumps and common rail pumps.
The answer to this problem is a high efficiency water separator and pre-filtration system that effectively removes water and particulates up to 30 microns from diesel. This will in turn reduces the load on OE fitted essential secondary filters and help them to work efficiently without causing fuel restriction.
Without a high efficiency pre-filtration system, the standard filters come with engine must work hard to remove all the contaminants. Secondary filters on most engines are fine filters with small pores of 5 micron or less. Therefore its efficiency and service life depends on the quality of diesel. It is in this context that one should look at an effective pre filtration system. Low restriction pre filter reduces overall pressure drop in the fuel system and helps improve the life and efficiency of secondary filters and FIP.
Aeration Damage
Most common problem of bio degradation is premature filter clogging, fuel injection pump malfunction or failure, injector malfunction or failure resulting in incomplete combustion. The problem with clogged filter is not as simple as commonly thought and it will not end with a usual replacement. When the filter is clogged, it creates a restriction in the fuel system causing the fuel pump to work with increased suction force; this high suction force causes tiny air bubbles to form. Air bubbles so formed become highly abrasive under pressure and causes irreparable damages to fuel injection pump and injectors.
Both Ecotech Fuelmag and SEPAR diesel water separator will help solve this problem thought to be impossible to solve. Both units are independent and work differently for protecting diesel.
These can be used in combination or independently as the situation warrants.
Based in informed opinion and field experience, both units installed in combination offer ideal protection of diesel engines against unpredictable fuel problems.
Clean, contamination free diesel would help reduce fuel injection system break down and enhance combustion
( For more information on Ecotech, Fuelmag and SEPAR 2000 , visit thewebsite www.ecotecindia.com. It has agraphical product demo to help understand its function or email pgt@ecotecindia.com)
