Measuring & Testing

Fast and reliable analysis

CFCS uses the handheld DieselProve test kits to carry out on-site tests

The growing use of liquid biofuels in stand-by generators has increased the need for effective fuel testing to confirm that bio content levels remain within the required limits.

With the introduction of new environmental standards and directives aimed at improving air quality, the low sulphur content, reduced carbon dioxide (CO2) and greenhouse gas emissions associated with biofuels have increased their use in a range of industrial and emergency power applications.

Although many different types of biofuels can be produced from a wide variety of biomass, the term biodiesel usually refers to Fatty Acid Methyl Esthers (Fame) produced from bio-oils generated from feedstocks that include rapeseed, palm oil and soya bean.

While 100 per cent biodiesel (B100) can be, and is, sometimes used as a fuel by itself, it is more commonly used as a blend component in conventional diesel.

However, genset engine tolerance of higher levels of biofuel content in diesel blends can vary enormously and most engine manufacturers set their own standards for liquid fuel use. While lower level blends may not require engine modifications or adjustments, the variations in fuel quality associated with some higher content levels of biofuels can impair engine performance and reduce power output.

In addition, the physical properties of biofuels can also cause damage to components so that the service life or the engine and manufacturers’ warranty conditions can be affected.

In the circumstances, to prevent potential reductions in power output and damage to engine filters, fuel injection systems and other components, specific biofuel content threshold limits are imposed for different power generation applications.

For example, in Europe, the quality of diesel fuel for automotive applications is specified by EN 590 which describes the physical properties that all automotive diesel fuel must meet if it is to be sold in the EU and which allows the blending of up to seven per cent Fame with conventional diesel.

In the industrial engines sector, manufacturers of gensets quote recommended biofuel limits of typically two per cent, but individual users can decide to vary the standards of fuel they prefer, in some circumstances even specifying no allowable bio content even though it may be allowed by the manufacturer.

The DieselProve test kits utilise RF technology

The DieselProve test kits utilise RF technology

All of these considerations mean that it has become essential for users of blended diesel to be able to accurately determine the biofuel content of the fuel feedstocks they are using.

One company involved in this field is the UKAS-accredited Contaminated Fuel Condition Services (CFCS). CFCS carries out a range of on-site diagnostic tests to assess fuel composition and quality for a wide range of mainly non-automotive applications – and particularly for industrial and commercial customers operating stand-by emergency power generators.

Given the importance of biofuel content in this business critical application, the company uses advanced sensor technology as a first stage screening tool to check diesel blend quality and composition.

The handheld DieselProve test kits used by CFCS utilise patented radio frequency (RF) technology to analyse the electromagnetic properties of the material under test to detect the number of particulates present.

The electronic hand held unit and integral probe provides accurate, real time in-field measurement of biodiesel content with the same accuracy as laboratory sampling methods. As well as detecting the proportion of biofuel present, other contaminants such as white spirit, petrol and water can also be detected.

Reliable and robust test results are displayed in seconds and can be downloaded to a supporting software programme for formal record keeping and reporting options.

At CFCS, the advanced RF sensor is used as a quick on the spot screening tool to determine whether further sample analysis is required. As well as testing against specific 0 per cent, 2 per cent and 7 per cent content limits for different applications, the company also uses the sensor system to detect less than 100 per cent biofuel content in those B100 applications where it is being used on its own.

Kevin Harrison, director of CFCS, said: “Blended diesel fuel quality can vary enormously and we’ve seen cases where customers have had problems with bad fuel that has caused catastrophic effects in terms of engine damage.

“Accurately assessing biofuel content is therefore a fundamental first stage requirement of assessing fuel quality. Monitoring and assessing fuel feedstock quality is therefore essential for preventative maintenance purposes.”