Diesel Fuel Purifier | Large Scale Application | Alfa Laval Centrifuge


Table of Contents

The Source of Contaminated Diesel

Crude Oil transporting rail cars need periodic cleaning. This is to remove accumulated sludge, waxes etc.
Diesel fuel is often used as the washing fluid for rail car cleaning. One facility used approximately 10,000 gallons of fresh diesel everyday. Reuse of the spent black diesel was desirable but not workable. This was due the water and sludge contamination of the diesel.
The facility owner was familiar with Alfa Laval centrifuges for diesel purification from his service in the navy.
The owner contacted Dolphin Centrifuge. He wanted explore the possibility of using on of our industrial centrifuges. He wanted to purify the diesel and reuse it.

Customer’s Old Process to Purify Black Diesel

The customer had sourced a chemical additive. This additive would drop out some of the impurities into a heavy ‘black phase’. The heavy phase would drop out over time. Finally, they removed this separated phase by decanting.
This was a time consuming process. It required manual labor and considerable tank capacity for decanting.

Pilot Scale Testing at Dolphin Centrifuge

Dolphin Centrifuge recommended pilot scale testing of the chemical diesel mix. We tested the mix in our in-house testing facility with our pilot scale disc centrifuge.
We mixed the desired ratio of the customer provided chemical into the black diesel. The mixed fluids were then processed through our pilot scale, disc-stack centrifuge.

Pilot Scale Test Results

The diesel purifier was able to separate the heavy phase and produced a stream of clear diesel. The separated heavy phase was flowing out the heavy phase outlet.
The customer got the purified diesel analyzed for impurities and water. The analysis results showed diesel with less than 0.5% impurities. This was definitely re-usable to clean out rail cars!
The customer awarded Dolphin a contract to build a 40 GPM diesel fuel purifier system.

Large Scale Diesel Fuel Purifier – System Details

The featured image on the top shows the system manufactured by us. The system included a chemical injecting port designed by Dolphin. We also integrated a dynamic mixing system on the inlet feed line to the centrifuge. Integration included electrical and mechanical aspects of the mixer.
We also integrated Flow-meters into the diesel and chemical lines. We used a PID loop to control both pumps to check and ensure a consistent diesel to chemical mix.
Dolphin Centrifuge’s engineering team did the site installation and commissioning . The system recovered the daily volume of used diesel during the night shift.

Reclaiming Used Black Diesel – Verified Field Results

The customer is reusing the diesel 2~3 times before refreshing the wash diesel stock. This resulted in annual savings of over $2M! The diesel purifier module paid for itself within the first month!

Technical Specifications of the Large Scale Diesel Centrifuge System


Contact Dolphin Centrifuge for pricing information or to discuss your specific application. We have a large inventory of diesel fuel centrifuges for sale.