Here's some pics received today from Vinny in Enniskillen. Vinny takes used vegetable oil and recycles into biodiesel for his van. Under tax leglislation changes introduced a year or two back, this is now legal and duty free if done for personal use, provided production is under 2500L per year.
Hopefully Vinny can post up a few notes on this thread explaining what the equipment does. All I know is that he's used an obsolete stainless hot water tank, cut the bottom off it and turned it upside down. A recycled central heating pump circulates the oil, and the old immersion from the tank provides the heat. Some chemicals such as meths and potassium salts are required to convert the oil to perfectly usable diesel. The only items purchased new were a few pounds worth of plumbing fittings - Fantastic!
Vinny's also provided a pic of some spare flat panel solar water heaters he has available - if anyone's interested drop Vinny an email.
here we see the top of the tank, which had originally been the bottom of the tank with the dished based now cut off with a grinder. On the left hand side you can see the top of the 3kw immersion heater element.
Thats great, I was going to set up one of these for myself a while back, but it became a bit irrelevant when my diesel van died on me.
From what I remember of the systems I was looking at back then they had a two tank system and used some pretty aggressive chemicals, Caustic Soda I believe, or Sulphuric acid, can't remember but it was one of those melt your hand off types
Anyway its great to see someone local (well in Northern Ireland) using Bio Diesel, hes the first I've heard off, although I have come across a few people using new vegetable oil mixed with diesel, and there was one guy who used filtered oil, but I'm not really sure what he was doing with it.
I've only heard of the two tank system for people running on either unused vegetable oil or filtered used veg oil. This setup is for biodiesel. this is entirely different from veg oil, and bio-diesel is interchangeable in all respects with fossil-derived diesel.
Perhaps if we had a few people collectively interested in making their own biodiesel for 'own use', & we could persuade a few local chip shops and restaurants to donate their waste, it might be a worthwhile thing to do?
I was speaking with Vinny again recently and I gleaned some more detail on how his homemade conversion system works:
Heat the used veg oil up to ~55 degress C
Take a sample and test with a biodiesel titration test. This tells you how much potassium salt (potash) is needed. Mix in the required amount of potassium with methanol in a separate mixer tank. About 20% meths is required. Pour the meth/potassium mix into the big tank and keep the pump running. The meths and potassium is designed to remove/separate out the very fatty deposits, glycerol etc.
The temp then needs raised to about 65 degrees and, with the pump running, water is sprayed on top of the big tank. The water some how combines with the salt and will ultimately be drawn off at the bottom. A fish tank type air bubbler is used too towards the end of the process but I'm not sure how exactly.
The water and fatty/glycerol waste is then taken to the local refuse centre. What's left is 100% usable biodiesel fit for any unconverted diesel engine.
The above are only rough notes and I have yet to get a proper understanding of the process. Will try and get some further detail in the next week or two.
As you say Biodiesel is pretty much interchangable with normal mineral biodiesel with a couple of points, biodiesel is generally cleaner than normal diesel and may lead to a cleaning effect on your fuel tank and pipes (cleaning out the deposits from the diesel you used previously) and can cause blocked filters after youve been using for a while. Biodiesel may also get more 'clumpy' at low temperatures, like sub zero, although it is worse in filtered and straight vegtable oil. There is also the issue of the smell, it gives off a distinct fried food smell, I must admit I kinda liked it. Whenever I stopped at the lights I would get a whiff of it, it always made me feel hungry.
If someone was setting up a biodiesel plant I'd certainly be willing to help, for what it's worth.
I was also reading about this guy that made his own biodiesel that used the glycol waste to make soap with, he was making it into bars and selling it as 'Black Soap' he said it reminded him of the old 'Carbolic' soap. His website seems to have died though.
First of all, could someone provide a link to information on the changes in taxation on bio-fuel? This is news to me and very interesting.
A few years ago I experimented with running an old Renault Laguna 2.2 on WVO with almost no modification. The fuel filter had a glow-plug at the bottom to thin the diesel in low-temperature conditions and I tricked this out with a switch and then removed the guts of the filter so that this created a well of pre-heated WVO of about half a litre. I got a fuel filter off a scrap Peugot 405 which had pre-heating provided by the hot water circuit and we left the fliter in this one and rigged it in series with the first one. That was it and the car started and ran fine in all sorts of temperatures.