Finishing methods

[Bill]

The problem is not so much what finishing method, it is that a finishing method is needed. If the conversion process didn't produce contaminated bio a finshing stage would not be necessary.
Not a solution but perhaps a different point of view.

[Tony]

Brian has raised a very interesting point on Daves thread regarding his issues.

So here are the two popular scenario's:

1.Water washing
2. Demething/recovery and then bubbling the balance of meth to atmosphere.

There maybe an additional process step with drywash towers.

Brian has said that water washing is wasteful...even if using harvested rain water?!.. and is looking via the forum for a "non wasteful way" of finishing fuel.

The question is....what are the alternatives?

Are there any alternatives?

Water washing uses water.....bubbling after demeth liberates methanol to atmosphere. Both could be seen as wasteful.

What, if anything is the answer?

I didn't mean to raise a point,I thought I asked how is a good way of removing the waxy flakey stuff,
It don't seem to settle but clings to the sides of the settling drum.
When this stuff is present it blocks my 1 micron filters I use.I do put jay cloths around filters but its a pain to have to keep changing cloths.
Perhaps it would be better to filter the fuel from the top of the settling drum via an anti siphon tube set near the bottom.
Leaving the flakey stuff"whatever it is"on the sides.
So how do you remove the waxy flakey stuff?

Right so my setup has a 12mm copper pipe bent into a J shape.  When I'm pumping out through the drywash tower to storage I have some wire that is attached to a nail in the shed above it which I use to progressively lower this J shaped bit of pipe into the settled bio.  When it's getting to the bottom it's pretty clear where any wax sits so I'm just careful not to disturb that.

[Tony]

The problem is not so much what finishing method, it is that a finishing method is needed. If the conversion process didn't produce contaminated bio a finshing stage would not be necessary.
Not a solution but perhaps a different point of view.

The way I see it there are two problems:

- the production of soap from water and free fatty acids; without water and free fatty acids this could be avoided (IE use ASM which doesn't contain water, and fresh oil)

- leaving methanol in the final fuel may potentially lead to further reaction in the fuel tank (producing glycerol); maybe this could be avoided by assuring a complete reaction?

So if you use fresh oil, ASM and ensure complete reaction, maybe you don't need to finish the fuel.

However that use of fresh oil is bit of a killer from our point of view.

[Bill]

Well, glad to see Tony's picked up the ball and running with it.
The only thing I can think of at the moment is some sort of pixie dust (yet to be discovered) which is added at the end of the reaction to kill all the excess methanol and catalyst and put it on the glycerol to drain off. Leaving clean biodiesel on top of course.

[Tony]

Well the old school method was ion exchange resin, which turned the soaps in the fuel back to free fatty acids.  But none of us are convinced that's a good thing to do to your fuel.  That said, from what I understand Carrington is running vehicles on high ratios of free fatty acids, so perhaps we are mistaken.

[Tony]

The table here states that free fatty acid is bad for injection pumps:

http://www.biopowered.co.uk/wiki/Effect_of_biodiesel_on_fuel_injection_systems

[nigelb]

I didn't mean to raise a point,I thought I asked how is a good way of removing the waxy flakey stuff,
It don't seem to settle but clings to the sides of the settling drum.
When this stuff is present it blocks my 1 micron filters I use.I do put jay cloths around filters but its a pain to have to keep changing cloths.
Perhaps it would be better to filter the fuel from the top of the settling drum via an anti siphon tube set near the bottom.
Leaving the flakey stuff"whatever it is"on the sides.
So how do you remove the waxy flakey stuff?

Brian, you were raising issues regarding wasteful practices on "Daves Flakey issues" thread. This is the reason I posted this thread.

Personally, unless anybody can come up with an alternative, economical and efficent way of finishing fuel that does not produce waxy & flakey deposits then any method of water washing is the answer.

In all the years and all the batches of fuel I've produced I've never seen any sort of post or after filter waxy deposit issues....apart from when I dipped my toes into demething.

Brian....have you done a search into my methods yet?

[whatarascal]

I didn't mean to raise a point,I thought I asked how is a good way of removing the waxy flakey stuff,
It don't seem to settle but clings to the sides of the settling drum.
When this stuff is present it blocks my 1 micron filters I use.I do put jay cloths around filters but its a pain to have to keep changing cloths.
Perhaps it would be better to filter the fuel from the top of the settling drum via an anti siphon tube set near the bottom.
Leaving the flakey stuff"whatever it is"on the sides.
So how do you remove the waxy flakey stuff?

Brian, you were raising issues regarding wasteful practices on "Daves Flakey issues" thread. This is the reason I posted this thread.

Personally, unless anybody can come up with an alternative, economical and efficent way of finishing fuel that does not produce waxy & flakey deposits then any method of water washing is the answer.

In all the years and all the batches of fuel I've produced I've never seen any sort of post or after filter waxy deposit issues....apart from when I dipped my toes into demething.

Brian....have you done a search into my methods yet?

No I have not Nige.,I am sure its probably the best way to produce and finish fuel.
As I wont be water washing,apart perhaps from a prewash  cant see the point in trawling through stuff that is of no use to me.
There are others on here who wont be water washing either,for all kinds of reasons,so even if we cant find an answer to the flakey waxy stuff we may find an easy way of filtering it out.

[nigelb]

Makes me wonder why you asked for details of my process Brian!

It strikes me that the way to avoid having to go through the efforts of having to filter it out...or drop the contents of the fuel tank when it really catches you out is to avoid producing them in the first place. ie having a water wash within the process.......and possibly to avoid any sort of demeth.

The demeth part may well be the common denominator. As previously said it may be feed stock related as well.

[nigelb]

Bill...I do like your way of thinking

[julesandtash]

I'm happy with my acid water washing.
20 litres of acid with a slug of concentrated sulphuric acid for the first wash then two 40 litre water washes then dry.

100 litres of water and 100ml or so of acid to wash 300 litres of bio doesn't seem that wasteful in my book.

Being water based it certainly seems to work with taking out any strange products in the fuel as I haven't seen any flakey stuff settling out anywhere.

[1958steveflying]

I'm happy with my acid water washing.
20 litres of acid with a slug of concentrated sulphuric acid for the first wash then two 40 litre water washes then dry.

100 litres of water and 100ml or so of acid to wash 300 litres of bio doesn't seem that wasteful in my book.

Being water based it certainly seems to work with taking out any strange products in the fuel as I haven't seen any flakey stuff settling out anywhere.

Do you test the Ph of your finished Bio ?

[Julian]

I'm happy with my acid water washing.
20 litres of acid with a slug of concentrated sulphuric acid for the first wash then two 40 litre water washes then dry.

100 litres of water and 100ml or so of acid to wash 300 litres of bio doesn't seem that wasteful in my book.

Being water based it certainly seems to work with taking out any strange products in the fuel as I haven't seen any flakey stuff settling out anywhere.

Do you test the Ph of your finished Bio ?

I also do a titrated acid wash and, like Jules find it pretty good.  Most times I'll test the pH of the final wash water and so far every one has come up neutral.

[Head Womble]

[Have you ever tried to clean a greasy surface with cold water ...

That's got to be the joke of the century, surely?

You've just asked Womble if he's ever tried to clean a surface ... have you seen the state of his shed?

I would take exception to that comment if it wasn't true.

[julesandtash]

Do you test the Ph of your finished Bio ?

I'm pretty sure you cant test the ph of biodiesel as it doesn't contain any water  (or shouldn't do any way).
This is why we titrate veg oil and partially converted biodiesel to ascertain an acid value as opposed to using a pH tester