Biodiesel - A First Reaction

Last October I wrote about my meeting with a waste vegetable oil man in Beccles, and talked about the beginnings of our Biodiesel group in Sustainable Bungay. This is an update based on a December visit to a man who makes biodiesel at home and our own first attempts at a reaction last Saturday.

But first, why am I part of a Transition Biodiesel group, when I don't even have a car at the moment? Well, for several reasons, not least the social benefits of being part of a community group that's making something useful together. But equally, at a time when oil prices are soaring through the roof and with political instability in so many oil producing countries, plus the realities of Peak Oil, it just makes sense to engage in a project that focuses my mind and gets me thinking in a really practical way about these things.

And you can use biodiesel for other purposes - oil lamps for instance. (Though there are obvious drawbacks with used chip fat - unless you're into things like scratch and sniff!).

(i)
On a very cold December day Josiah, Kris and I took a trip down to Aldeburgh to see Colin, a retired chemical engineer who has been making biodiesel at home now for three or four years. Colin welcomed us with a mug of tea and showed us around his set up, explaining the process - from collecting waste vegetable oils from food outlets through cleaning the dirty vegetable oil, reacting the clean oil with lye, separating the crude biodiesel and glycerol and washing the crude biodiesel with water to produce the final vehicle-worthy product you can see in the photos.

Throughout the visit Colin answered our questions on everything from handling lye (the caustic which is vital for the trans-esterification reaction which converts the vegetable oil to biodiesel and glycerol) to the disposal or recycling of the waste glycerol. He advised anyone making biodiesel for the first time not to rush into producing enormous amounts.
“The thing is to start small, doing the reactions with some glass or plastic bottles,” he said. “Then as you get used to handling the liquids, you can increase the amount.” This came as a great relief as I had been eyeing that caustic lye with some trepidation.

The legal limit for home biodiesel production is 2,500 litres per year, tax-free. This is what Sustainable Bungay’s Biosdiesel group will aim at initially. For the project to get underway properly we would have to wait for wamer weather. Colin meanwhile invited us to come round the next time he does a ‘reaction’.

(ii)
Last Saturday, 19^th February a dozen of us turned up at Kris and Eloise's to have a look at the set up in their garage and to make our first three litres of biodiesel. We crowded into the living room where Kris introduced the project and we discussed everything from logistics to legalities before descending on the kitchen for Eloise’s delicious soup and homebaked bread, David’s tasty flapjacks (his first ever!), Elinor's ginger cake (no comment required!) and Brenna's polenta, lemon and orange cake, also a first. I ate three slices of that!

Then we cleared all the food and utensils out of the way to do the reaction. Great care was needed (and taken) pouring the lye/methanol first into a glass measuring jug and then into plastic bottles with vegetable oil. As it was our first time (and the weather had not yet warmed up), we used clean vegetable oil, which does not go hard as lard in the winter.

Kris wore protective goggles and everyone handling the mixtures wore gloves. David and Josiah took photos. We kept the windows open to avoid suffocation by noxious fumes. My nervousness about caustic liquids was allayed both by the presence of Mike, a chemical engineer, and the fact that Kris was so calm.

We had to keep the temperature of the mixture at below 50 degrees for the reaction to take place safely (methanol is volatile and can produce an easily ignited vapour at higher temperatures), so the bottles were placed in a pan on the stove for about an hour. Meanwhile we went to look at the reaction vessel.

I had to leave shortly afterwards but here below is the result of our first biodiesel-making session.

Pics: Pouring the Oil (notice no gloves here!); Colin's Biodiesel; Pouring the Lye/Methanol mix (serious glove time!); Still in the Garage; First Bottle of Biodiesel - Photos by Josiah Meldrum, David Poston and Mark Watson