Biopowered - vegetable oil and biodiesel forum
Biodiesel => Chemistry and process => Topic started by: nigelb on March 04, 2013, 09:02:38 PM
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Following the testing for soaps on last weeks batch I thought I'd back up the testing and claims with the testing of this weeks as well. These results have now been published on the thread. http://www.biopowered.co.uk/forum/index.php/topic,995.0/topicseen.html
With a slight difference or addition to the testing I made attempts to quantify the claim that a post reaction wash of 7% water dramatically reduces the soap content of raw biodiesel. I figured that if a titrated value could be found and backed up with some real data...something I've not seen recorded anywhere..then it could have real benefits for the natural progression of this method. We all know it works...but to what extent.
However, the testing was less than successful with little or no colour change from the test sample. I suspect that the amount of 0.01N HCl used got in the way. It got to the point where I had injected 10ml of titrant and the solution started to take on a cloudy appearance having emulsified slightly with the sample and the IPA. I made two attempts to titrate but was met with the same issue on both occasions. Too much soap!
It makes me wonder whether a stronger version of titrant would help and then use a multiplying factor to give a ppm value. I can get my hands on some 0.5N HCl from work but I suspect this may be too strong. Or could I get away using a smaller sample of bio???
I've retained a sample of bio prior to the "prewash" so I've got something to play with.
Your thoughts please.
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I had the same problem trying to quantify the soap PPM on raw bio, just too high.
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How much titrant did you add before you realised it wasn't going to work?
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Can't remember exactly but at least 1/2 of one of your little bottles.
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Do you want some more....FOC
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Do you want some more....FOC
I'm ok for it atm but thanks anyway.
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I've just done a quick experiment with results that will need backing up the next time I make fuel.
Because I was unable to get a titrated soap test result on raw bio that has not been prewashed using conventional methods I decided to reduce the sample size to 10% of normal. Normal being 12ml.
1.2ml of untreated raw bio took 4.25ml of 0.01N HCl to change the colour to yellow.
(4.25 x 10) x 304 = 12,920ppm :o
A test of bio taken after the 7% post reaction wash with this fuel was 851.2ppm. A huge reduction
Could those who have test kits please undertake some testing when you next make fuel and post up when you have results. Thankyou
If this is right then the benefit of a 7% post reaction wash can finally be quantified with figures. As stated in my OP...we know it works but to what extent.
Nige
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So a 7% pre-wash removes 93.5% of the soap in the Bio, WOW!
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So a 7% pre-wash removes 93.5% of the soap in the Bio, WOW!
It needs more data to back up the initial test. I'm making no claims yet...just posting what I've foundso far. If it's correct it truly is a WOW moment.
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That is a hell of a reduction,
these findings make me it a hard decision, do we use the (dry) gly for prewashing or forget the gly prewash and go for post reaction 7% prewash.
I'm sure the 7% prewash is key to your water washing success, as far as I know you're the only one that does this in conjunction with water washing, it's normally only settlers that do the 7% thing.
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I glyc wash and 7% prewash.
Of the glyc drained down from stage one of the no tit process (18lts or so) just 4lts gets reintroduced to the reactor prior to the 7% water wash. This is to prevent the chance of any emulsion and is being reduced batch on batch. I used to pump 5lts back in.
This method means I have about 14lts of dry glyc for glyc weashing and an amount of glyc to prevent an initial emulsion when prewashing.
Best of both worlds.
I surely cant be the only water washer who has a 7% prewash as part of the process.
Don't get carried away with the initial ppm results Mark...It requires further testing before any claims can be made.
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Great idea that Nige, obviously works for you.
I've not heard of another water washer do a 7% wash, allthough it is a common practice for demeth and settle.
I'll put a post on here and VOD to find out if others are doing it.
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I think I experience the same sort of drop in post-reaction soap levels but by a different process.
I'm a recent convert to water washing due to the good results from the titrated acid wash method. My process is glyc wash, 2 stage no-titration and then I always bubble demethed.
On my first batch with water washing I didn't bother with the bubble demeth reasoning that the water washing will remove the remaining suspended glyc and methanol in the raw biodiesel. I also like to know what's going on with each batch so I always soap test before and after washing and sometimes inbetween washes.
Anyway, on this batch my pre-water wash soap levels were 4,576ppm (it may actually have been higher as I was taking samples for testing from the top of the reactor but now I make sure they're taken from the bottom). But this led me to have to do the acid wash and 5 water washes to get clean fuel which didn't seem very efficient to me. So on the following batches I reintroduced the bubble demeth stage. This is a no-effort part of the process as when I make a batch of fuel the glyc wash and 2 stage processing are all done in one day but there's never any time left to start washing. The bio is still hot so dropping in the air bubbler and letting it bubble over night allows another 1.5 to 2 litres of glyc to drop out (I do 80 litre batches). On the batch I've recently completed the post-bubble demeth soap level was 896ppm but on a previous batch it was as low as 288ppm! So including the bubble demeth stage means I only need to do the acid wash and 1 water wash to get clean fuel.
So I'd say that some sort of post-reaction process to initially drop the soap levels (whether it's bubble demeth, 7% post reaction wash or something else) is a very beneficial stage and greatly simplifies the water washing.
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I've not heard of another water washer do a 7% wash, allthough it is a common practice for demeth and settle.
I'll put a post on here and VOD to find out if others are doing it.
I demeth and settle but never do a 7% water prewash as I use the glyc for oil pre treatment, which includes a partial reaction which I understand it wont do with water in it.
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I made another batch of fuel today and performed a soap test on the raw bio prior to a 7% prewash. The results are:
Using a test sample of 1.2ml and a multiplier of 10 in the final calculation the bio titrated at 2.6ml of HCl. So 2.6 x 10 x 304 = 7904ppm
A sample of fuel taken after the post reaction wash titrated at 3.8ml of HCl. So 3.8 x 304 =1152.2ppm
The only variable this time with the process was the re-introduction of stage 1 glyc following a successful 5/45 and prior to the wash was only 2lts. A reduction of 50% on my last batch. Hopefully this will be reduced further on the next batch.
Perhapes some one could work out the percentage reduction in soaps for me.
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Around an 85% reduction son.
Soap content of batch 0.79% or 790ml of soap/100ltr
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Wow!
not too far removed from the first attempt.
This needs backing up by others who have the test kits.
Thanks Pops
Nige
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I'll test my next batch and post the results, should be next week.
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I tried 7% water prewash yesterday on a batch
300 litres of perfect pass biodiesel using two stage process and ASM
At the end of the second stage I left in the glyc from that stage and added 5 litres of glyc back from the first stage (took this from the top of the drum to capture the little bit of bio floating on it.
I then added 20 litres of water, mixed for twenty minutes the let it settle then drained. No emulsion.
After five 20 litre pump water washes and soap testing after each one, my final test was 0.025ml of HCL (or as close as I could estimate, between .45 and 0.50 on a 0.50ml syringe) which, multiplied by 304 gives 7.6ppm soap.
Got to be happy with that.
Nothing other than 120litres of water and a bit of glyc used to get 300 litres of bio with just about no soap. No acid, no acetone and really good results
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I finished a batch yesterday, much the same as you Julies, no acid wash and no emulsion.
Did you use your eductor when washing ?
I took samples from each stage and will test them and post the results later.
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I finished a batch yesterday, much the same as you Julies, no acid wash and no emulsion.
Did you use your eductor when washing ?
I took samples from each stage and will test them and post the results later.
No eductor, on the principle that I dont have one on the plant so cant use one :)
Just an 82lpm pump and 1" steel pipework throughout.
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I used my eductor, 110lpm pump, 28mm pipework, 500lpm tank turnover, 200L batch.
If I can do that without an emulsion it sure shows it works.
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I really want to pluck up the courage to not put any of the first stage glyc back and just put the water straight in at the end of the second stage with just the glyc from that stage. That would avoid a lot of faffing around.
I wonder if that will still work?
I guess if it goes belly up I could always put a bit of acid in to cure it and they proceed as per acid wash.
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Funny you say that, I used 3L of ASM for the first stage so there would be more gly in the second stage,
this way I didn't need to add any gly back in later.
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It appears that Nige's statement about the past is true.
Back to the original GL process then.
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Cool. Maybe I will try 4.5litres of ASM in my first stage then and not put any of the first stage glyc back in.
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It appears that Nige's statement about the past is true.
Back to the original GL process then.
What was the original GL process then Jim. I though he was an advocate of demething and settling not in processor water washing
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Garham always advocated a 5% post reaction water wash to massively reduce soaps in the final bubble dry and settle.
The post wash was dropped to increase the purity of the reclaimed methanol.
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Garham always advocated a 5% post reaction water wash to massively reduce soaps in the final bubble dry and settle.
The post wash was dropped to increase the purity of the reclaimed methanol.
I never dropped it for that reason ... I used to reclaim the methanol and then do a 5% wash with the remaining glycerine .. best of both worlds. I only stopped the 5% (or 7% as it later became) wash, because I started using the glycerine for Glogs.
I find acid washing without the glycerine works well for me now, and I still reclaim the methanol and recycle the glycerine.
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Well I'm shocked, I've just done the soap tests and this is what I got
Raw bio = 1428.8ppm
7% wash = 206.72ppm
wash 1 = 12.16ppm
wash 2 = 9.12ppm
wash 3 = 9.12ppm (by now it's hard to read such small differences)
wash 4 = 6.08ppm
Each wash used 15L of water (7.5%), pumped for 1hr with eductor running.
This batch was 200L of oil, using 3L of ASM for the first stage, 1.4L for the second stage.
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Wow interesting results - now you're tempting me back to 7% prewash :o
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You've got to try this water washing lark, I'm absolutely sold on it.
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Interesting that there was no change between washes two and three. To be honest, looking at your figures, there is nothing really to be gained after doing the first water wash.
The difference between 12.1 and 6.08ppm is negligible - 6ppm or 0.019ml of HCL which could almost be a measuring error.
I really must keep samples of mine on the next batch and record the results.
I did measure them but was in a rush and didn't write them down.
I seem to recall that it was not until the third wash that the soap values really started to plummet but then I was only doing 10 minute washes.
I will try a one hour prewash and a one hour water wash and see if that gives similar results to you.
How long do you leave it to settle between the prewash to first water wash and then between washes?
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I like to leave it to settle for 2hrs, the first wash was left overnight.
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Mark..I see your raw bio sample is really low in ppm value again....almost to the same point of my fuel after the 7% wash. Your two samples are quite consistant, as are mine.....just the level of ppm that's different. Would it be possible for you to send me a sample of your raw fuel for me to test. I could do the same for you.
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I think that would be a good idea Nige,
I'd like to get it checked by someone else as I'm not convinced my readings are right,
they just seem too low, I know your testing equipment is is probably more accurate than mine.
As we both do two stage non titration with ASM it's hard to see why are results are so far apart.
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Mark is your post 7% measurement directly after the prewash or after the 2 hour settle?
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Mark is your post 7% measurement directly after the prewash or after the 2 hour settle?
I don't get what you're asking mate.
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Mark is your post 7% measurement directly after the prewash or after the 2 hour settle?
I don't get what you're asking mate.
Perhaps I'm misunderstanding your process?
Do you?
1 - add prewash water
2 - mix prewash water
3 - turn off pump
4 - settle and remove glycerol
5 - stand for two hours
6 - remove any extra settled glycerol
7 - start first wash
In which case if you sample the soap PPM after step 4 and 6 there might be a difference
Or do you leave the settling glycerol in for the whole two hours, then take a sample?
I hope you see what I mean!
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I don't do 5 & 6.
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I think that would be a good idea Nige,
I'd like to get it checked by someone else as I'm not convinced my readings are right,
they just seem too low, I know your testing equipment is is probably more accurate than mine.
As we both do two stage non titration with ASM it's hard to see why are results are so far apart.
The basic test equipment I use is no different to the kit you have. The only difference for me...assuming you don't have one... is I use a magnetic stirrer and conical flask.
The important part of our two sets of results is the consistancy. ie there have been no wild swings in the results gained and the drop in ppm's have been expected.
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How long do you leave it to settle between the prewash to first water wash and then between washes?
I like to leave it to settle for 2hrs, the first wash was left overnight.
Ah so you are only talking about between washes not prewash to first water wash?
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How long do you leave it to settle between the prewash to first water wash and then between washes?
I like to leave it to settle for 2hrs, the first wash was left overnight.
Ah so you are only talking about between washes not prewash to first water wash?
Yes, sorry mate, I didn't read your first question properly.
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I think that would be a good idea Nige,
I'd like to get it checked by someone else as I'm not convinced my readings are right,
they just seem too low, I know your testing equipment is is probably more accurate than mine.
As we both do two stage non titration with ASM it's hard to see why are results are so far apart.
The basic test equipment I use is no different to the kit you have. The only difference for me...assuming you don't have one... is I use a magnetic stirrer and conical flask.
The important part of our two sets of results is the consistancy. ie there have been no wild swings in the results gained and the drop in ppm's have been expected.
I know the results should be the same, but my results are unexpectedly low and it would be nice to have it tested independently as it were.
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Nige, u2u me your address and I'll get some samples posted off.
I'll send you the raw bio, prewashed bio and the first wash as I think they are the most important ones for reference.
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Well I did a batch of 100% palm today for the boiler.
I just left in the second stage glyc, none added from first stage and all was fine - no emulsion
The whole lot is now settling overnight - hopefully all that water in the glyc will stop it from going solid
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Well I did a batch of 100% palm today for the boiler.
I just left in the second stage glyc, none added from first stage and all was fine - no emulsion
The whole lot is now settling overnight - hopefully all that water in the glyc will stop it from going solid
I think the main test is the first wash without acid, if don't form an emulsion then you've cracked it.
It would be good to find out at what post prewash soap ppm emulsion an is likely to form,
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Nige, u2u me your address and I'll get some samples posted off.
I'll send you the raw bio, prewashed bio and the first wash as I think they are the most important ones for reference.
Cool...you have a PM
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I personally think one of the main causes of emulsions was incomplete reactions back in the days of 27/3 testing !
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Jesus I cant keep up with this, the preferred process seems to change every week. I am almost ready to do my first batch and am a bit lost and my head is spinning. The acid wash seemed to be an epiphany moment and now its out the window?
Could there be a sticky main thread that details the different types of process and what they are most suited to? eg time of year/feedstock type/catalyst type/water wash or not etc etc
Maybe a Wiki page from one of you intelligent people like a flow diagram or something?
And if someone says it depends on what you have and what you want to do I will implode :(
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Some have started doing away with the acid wash, but it's early days and only a few straight water washes have been successful ... this could yet change. I'm still adding acid. Seems like cheap insurance to me.
If you are just starting out, I'd suggest starting right from basics and working your way through the various, recent variations.
Something I found surprisingly fascinating recently was doing a Dr Pepper test. Making a tiny batch in a glass jar or a pop bottle lets you see every stage as it happens and stands you in good stead for understanding what happens out of sight in your processor.
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Something I found surprisingly fascinating recently was doing a Dr Pepper test. Making a tiny batch in a glass jar or a pop bottle lets you see every stage as it happens and stands you in good stead for understanding what happens out of sight in your processor.
Yes I am going to do that this week funnily enough. It is just as I get what my process will be in my head someone comes up with something different and my head is spinning trying to keep up.
I think I will just go back to the basic process and expand from there as I get more experience. I would have been processing by now but had to upgrade my power supply to my garage.
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Aaaagggghhhh - didn't quite work.
Water prewash worked ok but when I added the water for the first water wash it made a lovely emulsion, thankfully thin enough to pump.
I've now had to add acid to split it so am back to acid wash for this batch.
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Aaaagggghhhh - didn't quite work.
Water prewash worked ok but when I added the water for the first water wash it made a lovely emulsion, thankfully thin enough to pump.
I've now had to add acid to split it so am back to acid wash for this batch.
Some have started doing away with the acid wash, but it's early days and only a few straight water washes have been successful ... this could yet change.
I know no one likes a "told you so", but told you so.
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Bad luck Julies, at least you had acid to hand ready to break the emulsion.
As I posted before I think I've only got away with it due to seemingly very low soap levels.
Did you test for soap ppm after the prewash ?
How long did you settle the first wash for ?
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Nige, u2u me your address and I'll get some samples posted off.
I'll send you the raw bio, prewashed bio and the first wash as I think they are the most important ones for reference.
Cool...you have a PM
Thanks Nige.
I'll get them posted off in the week.
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Bad luck Julies, at least you had acid to hand ready to break the emulsion.
As I posted before I think I've only got away with it due to seemingly very low soap levels.
Did you test for soap ppm after the prewash ?
How long did you settle the first wash for ?
I didnt test for soap ppm after the prewash and I settled the prewash overnight, drained this morning, first water wash this morning mixed for 45mins then left to settle for 2hrs. When I went to drain some it was mayonaise so I had a look in the top of the processor and it all looked like the gloop coming out the bottom.
Julian, thank you for you kind and supportive comments, I would never do such a thing to you :)
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Jesus I cant keep up with this, the preferred process seems to change every week. I am almost ready to do my first batch and am a bit lost and my head is spinning. The acid wash seemed to be an epiphany moment and now its out the window?
Could there be a sticky main thread that details the different types of process and what they are most suited to? eg time of year/feedstock type/catalyst type/water wash or not etc etc
Maybe a Wiki page from one of you intelligent people like a flow diagram or something?
And if someone says it depends on what you have and what you want to do I will implode :(
Your last line is right though, even if you do implode!
You use the method that works for you, your oil and your processor, they're all different and not one single 'in vogue' process will be right for everyone, and it's a blinkered approach to even think 'Joe Bloggs is doing that then so must I'.
Try a method a few times, see how it works, then if you're not happy change something in the process so it goes right next time.
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Julian, thank you for you kind and supportive comments, I would never do such a thing to you :)
Oh, come on, it's so rare that I'm ever right about anything, at least allow me a fleeting moment of glory!
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Enjoy the moment :)
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Jules, I've tried this twice now, both times I've done a test wash, Dr. Pepper if you like, before committing to the whole batch.
These have both started to split within 10 mins.
I later did the soap tests.
What I'd really like to do is enough testing to determine what soap ppm we can get away with,
as in below lets say for arguments sake 3000ppm is fine,
3000 to 4000 is borderline and above 4000 emulsion territory.
However I'm certain it wont work with NaOH and I've only got enough ASM for another 2/3 batches,
so unless I can gather funds and get some more relayed down I can't see it to the end.
Anyone fancy taking this up.
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Jules, I've tried this twice now, both times I've done a test wash, Dr. Pepper if you like, before committing to the whole batch.
These have both started to split within 10 mins.
I later did the soap tests.
What I'd really like to do is enough testing to determine what soap ppm we can get away with,
as in below lets say for arguments sake 3000ppm is fine,
3000 to 4000 is borderline and above 4000 emulsion territory.
However I'm certain it wont work with NaOH and I've only got enough ASM for another 2/3 batches,
so unless I can gather funds and get some more relayed down I can't see it to the end.
Anyone fancy taking this up.
Very fine reasoning young Womble ... like your thinking ... a most worthwhile plan. I'd offer but I'm only making bio once every couple of months at the moment.
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I think I will just go back to the basic process and expand from there as I get more experience.
This is the best way to go, that said I have a feeling you'll take to it quickly and be up to speed in no time,
you do need to make mistakes and learn from them, so every fail is still progress.
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Jules, I've tried this twice now, both times I've done a test wash, Dr. Pepper if you like, before committing to the whole batch.
These have both started to split within 10 mins.
I later did the soap tests.
What I'd really like to do is enough testing to determine what soap ppm we can get away with,
as in below lets say for arguments sake 3000ppm is fine,
3000 to 4000 is borderline and above 4000 emulsion territory.
However I'm certain it wont work with NaOH
Mark you are certain it wont work with NaOH ! . . does this stand for KoH ? If so why ?
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What caught me out was that the prewash didn't form an emulstomn. That worked fine, settled out nicely and, I though, all was lovely.
It was the first water wash that went wrong.
Having thought a a bit more about it, I wonder if the fact that it was 100% palm had any effect.
The water prewash was at around 60C still so the palm bio would have had a viscosity similar to any other bio.
But, overnight the temps dropped quite a lot which meant that this mornings water wash was, by the time the cold water had gone in as well, at around 35C.
Whilst still perfectly liquid at that temperature, I suspect the viscosity would have been higher. Maybe that is why the water stayed entrained. Perhaps if I had reheated to 60C then all would have been fine.
Maybe this could be all wrong but it is a theory. After all, the last batch I did was with all liquid oil and that worked fine.
The palm bio is all drying now and at 15ppm soap should all be good.
What really gets my goat is that I only did this for testing. Since the bio is just for the heating system, I could easily have just dried it after the prewash and used it. The boiler really doesn't object to a bit of soap in it's fuel.
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Mark you are certain it wont work with NaOH ! . . does this stand for KoH ? If so why ?
I suspect that it's because NaOH and KOH introduce water when they react with the methanol to form methoxide.
This water then goes on to form soaps, which means higher ppm soap in the raw bio.
Anhydrous Sodium Methylate doesn't add this water which results in lower soap formation (providing one uses dry oil of course).
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Mark you are certain it wont work with NaOH ! . . does this stand for KoH ? If so why ?
I suspect that it's because NaOH and KOH introduce water when they react with the methanol to form methoxide.
This water then goes on to form soaps, which means higher ppm soap in the raw bio.
Anhydrous Sodium Methylate doesn't add this water which results in lower soap formation (providing one uses dry oil of course).
Hmmmmmm. I washed my last KoH batch in pretty much the same manner as has been posted here without any emulsions.
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Jules, I've tried this twice now, both times I've done a test wash, Dr. Pepper if you like, before committing to the whole batch.
These have both started to split within 10 mins.
I later did the soap tests.
What I'd really like to do is enough testing to determine what soap ppm we can get away with,
as in below lets say for arguments sake 3000ppm is fine,
3000 to 4000 is borderline and above 4000 emulsion territory.
However I'm certain it wont work with NaOH and I've only got enough ASM for another 2/3 batches,
so unless I can gather funds and get some more relayed down I can't see it to the end.
Anyone fancy taking this up.
Very fine reasoning young Womble ... like your thinking ... a most worthwhile plan. I'd offer but I'm only making bio once every couple of months at the moment.
I like to say that as soap rich time poor you're not the right person to take the battern,
however I have produced a higher volume of soap than your good self, and still haven't even tried to recover it.
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Jules, could the palm oil still have been damp, we know it holds on to water compeared to most oils.
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Mark you are certain it wont work with NaOH ! . . does this stand for KoH ? If so why ?
I suspect that it's because NaOH and KOH introduce water when they react with the methanol to form methoxide.
This water then goes on to form soaps, which means higher ppm soap in the raw bio.
Anhydrous Sodium Methylate doesn't add this water which results in lower soap formation (providing one uses dry oil of course).
Hmmmmmm. I washed my last KoH batch in pretty much the same manner as has been posted here without any emulsions.
Steve, Jules is spot on as to my reasoning.
But the fact that you have successfully done it blows it right out of the water.
You say "in pretty much the same manner", what part differed from mine ?
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One swallow does not a summer make!
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Mark you are certain it wont work with NaOH ! . . does this stand for KoH ? If so why ?
I suspect that it's because NaOH and KOH introduce water when they react with the methanol to form methoxide.
This water then goes on to form soaps, which means higher ppm soap in the raw bio.
Anhydrous Sodium Methylate doesn't add this water which results in lower soap formation (providing one uses dry oil of course).
Hmmmmmm. I washed my last KoH batch in pretty much the same manner as has been posted here without any emulsions.
Steve, Jules is spot on as to my reasoning.
But the fact that you have successfully done it blows it right out of the water.
You say "in pretty much the same manner", what part differed from mine ?
Probably only timings Mark, oh and I only used stage 2 glyc, and of course I don't soap test.
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Mark you are certain it wont work with NaOH ! . . does this stand for KoH ? If so why ?
I suspect that it's because NaOH and KOH introduce water when they react with the methanol to form methoxide.
This water then goes on to form soaps, which means higher ppm soap in the raw bio.
Anhydrous Sodium Methylate doesn't add this water which results in lower soap formation (providing one uses dry oil of course).
Hmmmmmm. I washed my last KoH batch in pretty much the same manner as has been posted here without any emulsions.
Steve, Jules is spot on as to my reasoning.
But the fact that you have successfully done it blows it right out of the water.
You say "in pretty much the same manner", what part differed from mine ?
Probably only timings Mark, oh and I only used stage 2 glyc, and of course I don't soap test.
I also only used stage two gly, so only timing then.
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I ditched the 7% post reaction wash from the GL method a couple of years back.
Looks like it's now worth re-examining, with the 2 stage tit-less and 'glyc wash easier / more worthwhile' than WBD...
I am not keen on introducing extras into my process but a slug 'o old skool water's not too much extra work.
I will have a mess around with the % of water that I think the 'estimated stage 2 glyc volume' can take (1:1* ?) without any undue emulsion risk. That stage 2 glyc. vol. would be based on the first stage conversion:
i.e. for a 100L batch with 70% S1 conversion, S2 should give c. 6L of glyc....= ideal *vol. P.R. wash water to add.
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This is the best way to go, that said I have a feeling you'll take to it quickly and be up to speed in no time,
you do need to make mistakes and learn from them, so every fail is still progress.
Thanks Mark I think you are giving me far to much credit for the meagre intelligence I have. :-\
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This is the best way to go, that said I have a feeling you'll take to it quickly and be up to speed in no time,
you do need to make mistakes and learn from them, so every fail is still progress.
Thanks Mark I think you are giving me far to much credit for the meagre intelligence I have. :-\
I know you've done a lot of reading, and some of your posts have shown you have a reasonable understanding of the process.
As a classic car restorer your obviously a hands on person so should get on well with bio.
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OK, I've been convinced.
I did try a 5% water wash a couple of years ago. It formed the Mother Of All Emulsions and I ended up abandoning the batch.
I'll give it another crack (although maybe on my minimum of 100 litres just in case it goes wrong.)
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OK, I've been convinced.
I did try a 5% water wash a couple of years ago. It formed the Mother Of All Emulsions and I ended up abandoning the batch.
I'll give it another crack (although maybe on my minimum of 100 litres just in case it goes wrong.)
If you do form an emulsion it's easy to fix, just add a few liters of meths and it should split quickly.
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Or a small amount of any acid of your choice.
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...or some of your glyc!
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Earlier on in this thread I said I did not think this method would work with NaOH or KOH,
Steve (I think) said it worked for him with KOH.
Well I've now done a batch with NaOH, done the 7% prewash and then went straight into pump washing,
no emulsion at all (I did have some acid to hand just in case).
I'm going to try this again on my next batch and report back.