Is UNWASHED bio better to mix with SVO tha washed

[dagwill Senior Member Find all posts View Profile Close dagwill]

i get my wvo in 20 ltr containers,pour off the golden liquid and begin filtering, The bottom 5 or so ltrs i put aside as it will have solid crystals of fat visable in it. When i have 150 ltrs of crud i make a batch of bio with it. NOW ?? if i dont wash it any methanol will remain i think thats GOOD .Any excess caustic will remain but as i mix the bio back with my SVO wont that just neutralise some of the acids.
Any chemists out there please.

[RODEONICK Too Busy To Bio. Find all posts View Profile Close RODEONICK]

Re: Is UNWASHED bio better to mix with SVO tha washed

hey i found this post and wondered why it hadn't been answered so i'll have a go.

i was speaking to david the other day telling him about the crud in my filter that blocked. I thought that it was just a bad brew. david said that cos i wasn't doing a prewash or any water type wash ( i dry wash using a powder ) my reaction could still be taking place thus glycerine dropping out and this crud blocking the filters.
he said that he can tell when his biodiesel start tank supplier has washed or not by how long his filters last. He thiks that the reaction is continuing on through to the WVO by the return lines dumping the bio into the veg tank when switching between fuels. this seeems very probable to me. what do others think.
So the methanol in the proportion were talking shouldn't cause any harm maybe even a bit more go.
as for the neutralising of the acids it could come at the price of more frequent filter changes.
hope this helps all these years later.

[pangit Moderator Find all posts View Profile Close pangit]

Re: Is UNWASHED bio better to mix with SVO tha washed

I've never tried unwashed bio but I believe what you say is correct. I've read that th glycerin will continue to drop out in tiny quantities for weeks after the initial reaction if it's not washed. So it makes sense that the glycerin could be blocking filters.

When I asked Terry at the last BBQ about washing the bio he produces using his patented portable reactor, he said he hadn't washed for years. So maybe he can shed some more light on it but it doesn't appear to have done his engine any harm.

Anyway it certainly makes sense that the methanol still in the unwashed bio
would give you more power.

I've never had the confidence to try it unwashed myself, particularly in the Jackaroo althought I doubt the 300D would have any problems with it. I just prefer to make the best possible fuel I can, and I feel much better when I look at the crystal clear honey coloured fuel after it has been washed and dried.

[geewizztoo Senior Member Find all posts View Profile Close geewizztoo]

Re: Is UNWASHED bio better to mix with SVO tha washed

Anyway it certainly makes sense that the methanol still in the unwashed bio would give you more power.

Sean, I believe the oppopsite to be true. Methanol has about half the energy density of biodiesel (KJ per vol). By displacing some of the bio with meth you are reducing the energy contained in each squirt of the injector.

Now introducing methanol vapour into the air stream is a whole different kettle of fish and would be beneficial as you are replacing some of the air with more fuel (in diesels there is usually a surplus of air). Also the evaporative effect of the methanol will cool the incoming air.

Returning to Nick's point, I have run both washed and unwashed bio and I can concur that in my experience the filters turn chocolate brown and clog quite quickly on unwashed bio. Even though its been bubbled dryed for about 2 or 3 days and settled for a week or more before use.

And going back to Dagwill's original topic, unwashed bio will most likely be slightly alkaline due to the tiny quantities of moisture and residual by products. If this is mixed with WVO it may possibly neutralise some of the FFA with the side effect of making more soaps, salts and water as further by products. This may well be the contamination in David's filters as reported by Nick.