|Pilot OFR biodiesel rig at Cambridge|
Kwikpower International is licensing a process developed at Cambridge University that enables the continuous production of biodiesel using a mobile refinery.
Developed by Professor Malcolm Mackley and team in the Department of Chemical Engineering, the system uses an oscillatory flow reactor and was demonstrated at the Clean Energy Technology Show in London earlier this year.
Oscillatory flow reactors (OFR) exploit the uniform and efficient vortex mixing that can be achieved when an oscillatory fluid motion interacts with orifice plate baffles in a tube.
OFRs are well-suited for performing long residence-time reactions but with a form factor much more compact than a conventional tubular reactor—in other words, a good technology for a mobile application.
Not only can use of an OFR result in a smaller reactor, it can also enable the conversion of a batch process (such as conventional biodiesel production) to a continuous process, improving the economics and even perhaps reducing the residence time.
Kwikpower’s engineering subsidiary is already at work integrating the new reactor design into a continuous production module which will fit into a 40-foot container.
This technology offers real promise to allow us to reduce the time and cost of production of bio-diesel from a variety of feedstocks, allowing bio-diesel to compete on a level playing field with crude oil derived diesel.—Dr. Jim Watkins, CEO and Chairman of Kwikpower
|Flowchart of OFR biodiesel pilot plant|
In its work on the OFR biodiesel reactor, the Cambridge team also developed a continuous settler/coalescer unit to separate the biodiesel from the glycerol major by-product.
Biodiesel produced at this stage contains excessive levels of methanol, and must be waterwashed. The team developed a continuous countercurrent oscillatory wash column. This is followed by a coalescer (a sand-bed), which forces most of the water suspended in the biodiesel from the washer to coalesce into a separate phase.
This step is followed by a salt drying bed to remove the small amounts of water remaining after the coalescer. The last two unit operations are essentially the same as those used in the petrodiesel industry to remove water.
The £1.25 million (US$2.2 million) technology transfer deal was enabled by UTEK, a company focused on matching up innovative technologies from universities and research laboratories worldwide innovative with corporate buyers.
Photos of the biodiesel rig at Cambridge
“A Mixing-Based Design Methodology for Continuous Oscillatory Flow Reactors,”Chemical Engineering Research and Design, 2002, doi: 10.1205/026387602753393204
“Process intensification of biodiesel production using a continuous oscillatory flow reactor,” Journal of Chemical Technology & Biotechnology, Volume 78, Numbers 2-3, February/March 2003, pp. 338-341(4), doi: 10.1002/jctb.782"