BIODIESEL & SVO DISCUSSION FORUMS





Sponsors    Biodiesel and SVO Forums Home    Forums  Hop To Forum Categories  Biodiesel Connections  Hop To Forums  Ireland Biodiesel    Caustic stripping.
Page 1 ... 8 9 10 11

Moderators: Shaun, The Trouts
Go
New
Find
Notify
Tools
Reply
  
Caustic stripping.
 Login/Join
 
Member
posted Hide Post
Good Point IMB.

I have only been stopped once since making bio. The fuel was checked for kerosene (similar colour in the U K with it's yellow marker) and I was respectfully reminded that I could only make 2500 litres per year (before duty was payable) which of course I knew.

Just imagine the explainations if the colour was very dark or at worst using black diesel (derived from WMO)!
 
Location: YORK UK | Registered: April 27, 2014Reply With QuoteReport This Post
Member
posted Hide Post
Driving a vehicle on black diesel (WMO) here is a criminal offence carrying a fine of up to €2700. A very dark coloured fuel would be viewed as suspicious by the revenue and your vehicle is likely to be impounded while you prove that you were not driving on black diesel.
 
Location: Lismore Ireland | Registered: November 25, 2007Reply With QuoteReport This Post
Member
posted Hide Post
Really! My goodness, they do seem to be keen over there.

I think here the black diesel limit is the 2500litres/annum, same as bio.

When you perfect your method of biodiesel from lard, I'll have a go at it. There seems to be a minimum of colour, I like that.
 
Location: YORK UK | Registered: April 27, 2014Reply With QuoteReport This Post
Member
posted Hide Post
DGS, if your oil only titrates at 5 why would you bother with stripping or AE?
They dip tanks here looking for coloured fuel too, I hear they are putting some kind of radio active marker in it now too, with that they just hold a sniffer up to your fill pipe, or so I am told.
So far we have been lucky here in Ontario with no limit or taxes on homebrew... I hope it lasts as I know other provinces are taxing and/or limiting its use on road.
I really cant see the dark bio being a problem with the law though, just tell em to smell your exhaust! Smile
What do you want to know about processing lard? I have processed it a few times, makes beautiful bio!
Just dont use it when its going to get down <15C or your filter will plug with snowflakes...
You process it the same way as any other WVO, you just need to keep it hot to keep it flowing, I used a hot plate to warm the alcohol and lard for the titration.
If your not set up to vacuum dewater I would recommend a glycerin pre-treatment to get it good and dry as the hydrogenated stuff holds the water a little more stubbornly.
Another warning, if your using NaOH beware as the glycerin setts up very quickly when processing lard, its quite solid too...
Cheers,
Jon
 
Location: Wellington County, Ontario Canada | Registered: February 07, 2008Reply With QuoteReport This Post
Member
posted Hide Post
Hi Jon
Ive been making small batches of tallow biodiesel this summer and as you say it makes beautiful bio but starts to give problems below 15°C. I experimented with a process called fractional crystalization where the temperature of the bio is reduced very gradually and the snow flakes are filtered out as they form. This worked well and I was able to get the cloud point down to 7°C.
I want to restart the project because our night time temps have fallen to close to 0°C now and I can continue without refridgeration. However this is getting a bit off topic so Ill post on the biodiesel from lard thread when I get going again.
 
Location: Lismore Ireland | Registered: November 25, 2007Reply With QuoteReport This Post
Member
posted Hide Post
Sorry to drag it off topic, I just noticed your lard thread and I posted my filtering method there.
Cheers,
Jon
 
Location: Wellington County, Ontario Canada | Registered: February 07, 2008Reply With QuoteReport This Post



Member
posted Hide Post
[QUOTE]Originally posted by Jon Heron:
DGS, if your oil only titrates at 5 why would you bother with stripping or AE?


Jon, thats an easy one, my oil used to be badly contaminated with water, I thought it was my process, so went over to AE.

The other simple answer to your question is that for my first 2 years of making bio I was fudging around in the dark.
Should have read this forum earlier!
 
Location: YORK UK | Registered: April 27, 2014Reply With QuoteReport This Post
Member
posted Hide Post
If your oil was contaminated with water Im not suprised you found AE a pain in the ass. I did AE for a couple of years and the two golden rules were a scrupulously clean processor ( or a processor for acid only) and bone dry oil. But even then occasionally it would not reach the target titration in one go and sometimes had to be reheated and remixed.
Again I want to stress Im not an opponent of AE, there are pros and con to both methods.

A customer of mine caustic stripped a 150litre batch of oil titrating at 10ml KOH this week. He heated up the oil to 60°C and added the NaOH solution. Mixed with the paint mixer for 10 minutes, added 30 litres of glycerol, turned on the pump and went off for 20 minutes. Came back later turned off the pump and left it to stand overnight.
Unfortunately he had not noticed that his pump was not working. Instead of mixing with the oil the glycerol just sat as a layer below the oil. The oil water and NaOH went into full saponification mode and the following morning he had a processor full of white soapy jelly.
If I ever needed a demonstration of the role of glycerol in stopping the soap reaction that was it.
Poor Des had a horrible time cleaning out his processor.
 
Location: Lismore Ireland | Registered: November 25, 2007Reply With QuoteReport This Post
Member
posted Hide Post
Hi All,

Thought I would weigh in with some more information.

Been working on my process and its been a 2 step forward one step back saga.
Been fun, to do new work on making BD, so far the results have been less than stellar.
Hopefully I am getting closer.

Decided to use the Waterless stripping method for my last batch.

Dried 225Ltrs of 8 NAOH oil to <500 PPM

(Pulling Silica Gel dried air thru my processor with a vacuum pump worked very well in drying
4000 PPM oil).

Trouble started when I added My Methoxide ( 4G/Litre 900GMS NAOH) mixture to the room temperature Glycering ( 40 Litres). The Gly immediately started forming a solid soap. I plugged my processor pump trying to move it into the reactor.

A transferred the oil and chunky Glycerine to a COne bottom tank and mixed it with a drill
paddle stirrer and broke everything up as best as I could. After settling off the chunks,
I was able to move the mixture into the processor and separate out the
Gly and Oil.

Following that process the titration fell from 8 to 4 NAOH.
Marginal result, but I proceeded with processing as I had no more GLY to try again.

Dried the oil from 3-4K PPM down to 500PPM.

Processed with 80/20 ( 22% Meth and 9Gms/litre NAOH).

The second stage didnt create any additional glycerine, which was wierd. Unfortunately I didnt run a 3/27 test between Stage 1 and stage 2, Perhaps I had a complete conversion after stage 1.

Following stage 2, the fuel passed a 3/27 just fine, so I demethed and moved the output to
my settling tank. Immediately I started seeing soap on the surface of the tank.

The result has been a quantity of floating soap that I have never experienced before.
I am scooping it now. Probably will be 20-30 litres of soap when I get it all out.
SInce its floating, I am chasing it around the top of the tank!

Yikes!


Not sure how to avoid the hard soap in the GLY
also
need to avoid the massive soap production in the finished BD.

Thoughts?

Thanks all,
JOhn
 
Location: Georgetown, KY | Registered: July 31, 2007Reply With QuoteReport This Post
Member
posted Hide Post
Its worse than I thought. After scooping soap for a while the volume wasnt diminishing.

I reach down into the settling tank and its soap chunks down to my elbow. Massive.


Im thinking that this is because I had fully converted fuel prior to running stage 2.
Am I correct in that thought?

Thanks!
 
Location: Georgetown, KY | Registered: July 31, 2007Reply With QuoteReport This Post
Member
posted Hide Post
Jturbo68,
As you say, maybe you didn't need to do a second stage.

I have added NaOH to my glycerol, but about only 1gm/litre.
It did go a bit gloopy but nothing like the effect you describe, my glycerol was derived from KOH.

What is strange is that you dried your oil, then added your "enhanced" glycerol which reduced your titration by 4.0
This should have increased the water by 1800ppm and you say the water was 3 to 4000ppm. Strange.

Remember that when you added your methoxide to your oil that titrated at 4.0, the FFA's responsible for your titration would liberate another 1800ppm water. This amount is plus the water left in your oil, plus the water in the methoxide.

Could it have been this water that caused your excess soap, or a combination of the water and the possible unnecessary 2nd reaction.
 
Location: YORK UK | Registered: April 27, 2014Reply With QuoteReport This Post
Member
posted Hide Post
Sounds like you hit it with way too much caustic.
Check that your titration solution is fresh.
Let it sit for a couple weeks and all of the soap will form a cake on the bottom and you can pump the fuel off the top.
Cheers,
Jon
 
Location: Wellington County, Ontario Canada | Registered: February 07, 2008Reply With QuoteReport This Post



Member
posted Hide Post
I recently received 90 litres of pretty disgusting oil that came from Indian and Chinese takeaways. I was thinking of leaving it until Spring to process, but the sight of the dirty drums hanging around irritated me, so I decided to bite the bullet and load my processor.

Once it was sitting there and filling my bio room with all the exotic spices of the orient, I pondered how best to tackle it. Firstly I added some reasonable oil to make up a full load (220 litres) and then titrated. The result was 6KOH, and given that the oil was really wet (I'm sure the nasty smell is mostly down to the water bound up in WVO), I decided to reduce the titration using IMB's wet Caustic Stripping method.

I followed IMB's recipe exactly, using 2.5g/l of caustic soda I purchased from Wilkos. The result was a reduction in the titration to 0.75KOH. Fantastic!

I dried the oil for several hours using the turbo dryer, by which time it was smelling much sweeter. I then decided to try and neutralise the oil completely using the DGS enhanced glycerol technique. The only problem was that I had no spare glycerol, so I reused the stuff I had just drained out following the IMB wet process. I guess this glycerol was really wet, but I went ahead anyway and added a small amount of methoxide to the cubie of glycerol (225g KOH in 2.5 litres methanol). I know this is more KOH than DGS recommends (he works on halving the titration number to give the g/l of KOH to use in the enhancement of the glycerol), but from my discussions with him, we have both agreed that these really bad quality oils take a greater chemical quantity that good oils.

I added the enhanced glycerol and mixed for one hour at 55C. All seemed to be going well, and so I
took advantage of the residual heat in the oil to dry it even more using the turbo dryer for a further 12 hours.

When I removed the turbo dryer, the glycerol was still mostly in suspension (not surprising given all the agitation from the bubbles). In fact it took about three days for all the glycerol to drop out, leaving lovely clean oil in the processor that titrated at just over 0KOH.

I processed at the weekend, and the batch has converted remarkably well. For my first stage I used 9g/l, which resulted in a dropout of 0.5ml on the 10/90 test. For the second stage I added a further 1g/l, and this gave me an immediate clear pass. I normally use around 12g/l in total, so this was a good result (although I realise that in the course of caustic stripping I had used a further 1g/l to enhance the glycerol and 2.5g/l of caustic soda for the initial IMB wet stripping stage).



I am currently in the process of pumpwashing the batch, but I am more than happy at how it has turned out.

I like the IMB technique, as it quickly cleans up and neutralises even nasty wet oil, using a base (caustic soda) that is cheap and readily available. The result is even better when the titration can be further reduced using the DGS enhanced glycerol method. I don't have unlimited amounts of fresh glycerol hanging about, but my own experimentation over the weekend has shown that it is perfectly possible to use the glycerol drained out after the IMB wet stripping to carry out the DGS enhanced method.

Thank you both.
 
Location: Leeds, UK | Registered: April 13, 2014Reply With QuoteReport This Post
Member
posted Hide Post
Hi David,
a few thoughts and questions

quote:
Originally posted by David Shinn:
I added the enhanced glycerol and mixed for one hour at 55C. All seemed to be going well, and so I
took advantage of the residual heat in the oil to dry it even more using the turbo dryer for a further 12 hours.

When I removed the turbo dryer, the glycerol was still mostly in suspension (not surprising given all the agitation from the bubbles). In fact it took about three days for all the glycerol to drop out, leaving lovely clean oil in the processor that titrated at just over 0KOH.
I doubt that the "enhanced" method will be of much use if the glycerine is wet.
You added 1g KOH per litre WVO in the "enhanced" wash and achieved less than a 1 point drop in the titration number and then had to wait 3 days more for the glycerine to all settle out.
I think you would have been better off just putting that extra gram of KOH into the first stage reaction and saved the three days of settling.



quote:
I processed at the weekend, and the batch has converted remarkably well. For my first stage I used 9g/l, which resulted in a dropout of 0.5ml on the 10/90 test. For the second stage I added a further 1g/l, and this gave me an immediate clear pass.
How much methanol was in the first stage and the second stage.


quote:
I normally use around 12g/l in total, so this was a good result (although I realise that in the course of caustic stripping I had used a further 1g/l to enhance the glycerol and 2.5g/l of caustic soda for the initial IMB wet stripping stage).
Do yo mean that you normally use about 12g KOH per litre of WVO titrating around 0

This message has been edited. Last edited by: Tilly,






 
Location: ลึก ประเทศอินเดีย | Registered: March 03, 2001Reply With QuoteReport This Post
Member
posted Hide Post
Very good report David, I'm pleased it turned out so well.

Just a thought, next time you need to report, just go onto the caustic stripping thread on the PM posts.
 
Location: YORK UK | Registered: April 27, 2014Reply With QuoteReport This Post
Member
posted Hide Post
Hi David, Im glad that using the glycerol twice worked ok for you but in some circumstances it might not. It depends on how much soap and water it has absorbed from the caustic stripping stage. If your oil had titrated at 10 or above I suspect it might not have turned out so well.
With oil that titrated at 0.75, I would have cracked on with a two stage process. Ive often tested brand new oil at above 0.75 KOH.
 
Location: Lismore Ireland | Registered: November 25, 2007Reply With QuoteReport This Post
  Powered by Social Strata Page 1 ... 8 9 10 11 
 

Sponsors    Biodiesel and SVO Forums Home    Forums  Hop To Forum Categories  Biodiesel Connections  Hop To Forums  Ireland Biodiesel    Caustic stripping.

© Maui Green Energy 2000 - 2014