Aug-2020

Analyser delivers fast quality checks for biorefinery (TIA)

The demand for biofuels has increased in recent years, with the EU requiring that 10% of the total transport fuel in its member countries is to come from a renewable energy source in 2020.1

Evan Thomas
XOS

Article Summary

In addition, the US Energy Information Administration anticipates between 18% and 55% growth in biofuels production over the next 30 years.² While biodiesels typically contain little sulphur, they are still required to meet compliance specifications for fuel quality, either for use in vehicles or as a blending feed for traditional refinery fuels. As such, biorefineries must measure the sulphur in their product to ensure it is below regulatory limits, typically less than 15 wtppm. In addition to this, due to the variety of feedstocks online, analysis of biofuels can be challenging due to changing sample composition.

XOS’s Sindie 6020 online total sulphur analyser uses monochromatic wavelength dispersive x-ray fluorescence (MWDXRF) to measure a sample stream continuously and non-destructively, and to deliver results at user defined intervals. The analyser uses a dynamic window module (DWM) to automatically replace the sample window, which effectively eliminates any drift and significantly reduces the frequency of required calibrations. This, in addition to the rugged design of the analyser, reduces the time and frequency of required maintenance, leading to an uptime as high as 98%.

In August 2019, a Sindie 6020 online total sulphur analyser was installed at the Malchin biofuels refinery of ecoMotion GmbH by 360KAS, XOS’s exclusive distributor in north-west Europe. This site is one of the first biodiesel pilot plants built in Germany and has been in operation since 2001. The primary feedstocks for this plant are animal fats, vegetable oils, and waste cooking oil. The site produces 10000 tonnes of biodiesel annually (see Figure 1).
The core process in biodiesel production is transesterification. In this chemical exchange reaction, the glycerine contained in the primary material is replaced with methanol. This leads to the formation of fatty acid methylester (biodiesel) and glycerine. When converting animal fats and waste frying fats, the production process has two additional steps that are not required in conventional biodiesel production. In the first step — prior to transesterification — the free fatty acids contained in the primary material are esterified. After transesterification, the product is distilled. The result is a pure, crystal-clear and almost colourless product.

The expectation was to continuously measure the sulphur concentration in the biodiesel to confirm that the site was producing a product compliant with the climate protection targets set by the European Union. Previously this required the site to send samples to a remote lab which introduced delays and uncertainty in their production. By installing Sindie 6020 online sulphur analyser, the site obtains a measurement every five minutes, enabling operators to optimise their production, be confident their product is compliant and of high quality, and reduce their gas consumption by 5%.

Almost a year after installation, the site has reported that expectations for the performance of the analyser continue to be met, the analyser continues to operate without any problems, and the measured values match laboratory cross checks.

References
1 https://ec.europa.eu/energy/topics/renewable-energy/biofuels/overview_en
2 www.eia.gov/todayinenergy/detail.php?id=43096

This short case study originally appeared in PTQ's Technology In Action feature - Q3 2020 issue.

For more information: kolmsted@xos.com