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By what I keep reading from jamesrl.....

They are using a venturi to introduce methoxide into the reactor/processor. I'm not sure this is absolutely necessary. I figure the methoxide could just be pumped in with the pump. If this is the case, the 10% step (half step) could probably be skipped.

Jamesrl will have to comment on this to be sure. I would like for him to try it and let us know.

The actual process seems to be pretty straight forward from what I read.

I think most of this is pretty superficial. The titration is the part I want to get ironed out. I'm wondering if we could just use the regular method of titration, and process with the AAF steps.

James L
 
Location: Central Alabama (Marion Junction) | Registered: February 20, 2010Reply With QuoteReport This Post
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I do not see any reason why it could not simply be dumped in through a port
 
Location: New Orleans | Registered: December 31, 2007Reply With QuoteReport This Post
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I to agree that should work. This is based on Paddy's video. He clearly states the methoxide is first introduced, and then the oil is mixed into it.

James L
 
Location: Central Alabama (Marion Junction) | Registered: February 20, 2010Reply With QuoteReport This Post
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I don't think there is anything magical about their use of the venturi to inject. This just standard for the GL processor. The 10% oil is only needed to get enough pump output for the venturi to work. As soon as I get a preheat tank ready to go I'll be giving this a try.

Tony


2002 Ford Excursion 7.3l
1983 Mercedes 300D
GL processor
You're not finished when you lose,
You're finished when you quit.
 
Location: Tampa, Fl | Registered: April 27, 2007Reply With QuoteReport This Post
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Tony,

The magic of their venturi in not the injecting, it is the demething.

After their process is done, the use the venturi to circulate the vapors through a condenser to remove the methanol. This is a great design, especially if we can ever get the information about the flash vaporizer.

James L
 
Location: Central Alabama (Marion Junction) | Registered: February 20, 2010Reply With QuoteReport This Post
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-10% wvo first was to get sufficient liquid in the tank so the mixing could take place and to allow the ventury to work so the methoxide could be sucked in.

-the T is another thing, using this method we will use less caustic,(this part reminds me of the ledandary fool proof method) but to me thats the reason this process requires such dry wvo. what if we carry on with our normal titration and just add the methoxide first. If this could work then the problems I read about following ae should be eliminated. Tom


" I don't know what I don't know until I know"
1994 GMC 6.5 Tubo 2005 Dodge ram 3500, 3 VW's 2000, 2002, 2005.
 
Location: Manitoba Canada | Registered: March 24, 2009Reply With QuoteReport This Post



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BUCKEYE

WHERE are you!!! we are talking sodium bentonit here!!! Big Grin Big Grin Tom


" I don't know what I don't know until I know"
1994 GMC 6.5 Tubo 2005 Dodge ram 3500, 3 VW's 2000, 2002, 2005.
 
Location: Manitoba Canada | Registered: March 24, 2009Reply With QuoteReport This Post
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quote:
Originally posted by Biotom:
-10% wvo first was to get sufficient liquid in the tank so the mixing could take place and to allow the ventury to work so the methoxide could be sucked in.

-the T is another thing, using this method we will use less caustic,(this part reminds me of the ledandary fool proof method) but to me thats the reason this process requires such dry wvo. what if we carry on with our normal titration and just add the methoxide first. If this could work then the problems I read about following ae should be eliminated. Tom


This is my point also.

The 10% in will depend on the methoxide introduction technique. If you are using the pump itself (probably not the best method....seals and what not), then it could go in first. If using an injector/venturi, then you will need some oil to start the vacuum pulling it in (probably the preferred method).

I too, wonder if we can just titrate with our normal process and continue with the AAF method. Will we save KOH/NaOH? I hope so......

I am working on laying out my GL1 version (on paper/computer first). It will be very similar to Graham's. I do want to include all the updates which are new. I would like to know more about the flash operation, but jamesrl is doing safety testing. He will probably not release any information until he has all the fail safes worked out.

James L
 
Location: Central Alabama (Marion Junction) | Registered: February 20, 2010Reply With QuoteReport This Post
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Biotom,i think you will have to get in touch with Jamesrl or Paddy if you want more info from the land of Benny hill,you seem to have most of what has been posted already,not too sure who else if anyone uses the Arse about face method over here
Keith
 
Location: OXFORDSHIRE | Registered: October 07, 2008Reply With QuoteReport This Post
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Hey Guys,

When using a true TANK eductor there must be sufficient head volume above the eductor because the additional mixing (typically 4 to 5 times the flow rate through the eductor) is gained by the suction of the tank volume into the eductor head created by the increased velocity of fluid through the nozzle and the vacuum (or suction) created in the 360 deg. space around an behind the jet/nozzle.

So it could very well be true that the adding of the 10% volume is being done to support this eductor however they may have inadvertently stumbled on to the following:

The addition of dry preheated oil to preheated catalyst and methanol mixture has been around for over 10 years. It is the standard operating practice of the high temp. pressure reactors originally designed and marketed by Dick Carlstien of Biofuels SA. He has licensed his technology to various other companies over the years - including Biofuels Canada, UK Biofuels, BioKing, Etc.

Anyway there are several reasons why this is effective but for this conversation I will focus only on the 10% initial addition of oil and then the remaining 90%.

1) In larger operations (larger than Appleseeds) it is common to mix biodiesel (off spec or otherwise) back into the batch reaction to reduce overall FFA percentage (and to reclaim off spec fuel). In doing this it has been found that biodiesel in 10% to 15% of batch volume actually can reduce catalyst requirements due to its co-solvent effects (it acts as a bridge between the immiscibilty of methanol and oil). This can significantly improve reaction kenetics and prompt methyl ester formation.

2) With adequate mixing the vast majority of the methyl ester batch reaction occurs in the first 15 minutes (@ 140 deg. R) Therefore when adding the initial 10% of oil; I going to assert, that the oil is rapidly converting to methyl ester and producing this co-solvent effect.

3)And this brings me to the final point: Methanol to oil ratio. The protocol of adding oil to the methanol catalyst mixture significantly increase this ratio for the oil initially added. This includes the 10% and then later the other oil as well which then also benefits from the co-solvent effect. This high methanol to oil ration improves reaction also -- of course this comes to an equilibrium as glycerin production increases and can begin to interfer however that is probably overcome by the use of 2 tank eductors James set-up.

Lastly an often forgotten fact is that eductors typically apply quite a bit of back pressure on a tank recirculation system. Some people might think that this back pressure and subsequent lower flow rate can be overcome by adding a second eductor or second flow path but unfortunately the eductors effectiveness is dependent of proper operating pressures (larger 1.5 inch eductors really need about 70-80 psi) So even though the second flow path will increase total flow it will unfortunately reduce overall system pressure generated by a single pump recirc. system...

GCG
 
Location: Michigan | Registered: May 08, 2007Reply With QuoteReport This Post
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GCG
-interesting post, I'm sure we're not done with you yet Big Grin Tom


" I don't know what I don't know until I know"
1994 GMC 6.5 Tubo 2005 Dodge ram 3500, 3 VW's 2000, 2002, 2005.
 
Location: Manitoba Canada | Registered: March 24, 2009Reply With QuoteReport This Post
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Just to clarify... I wasn't speaking of 2 eductors but a 2-stage eductor

Cribbed this from a Chug post... thread: 2-stage conundrum

ImageTwoStage.JPG (21 Kb, 56 downloads)
 
Location: New Orleans | Registered: December 31, 2007Reply With QuoteReport This Post



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I had a revelation while watching the video for the third time.

I think Paddy has a very interesting idea......try to follow my thoughts.....

He is using the exact materials to find the titration point. Now this is very important for a few reasons. First he doesn't care what the pH of the solution is (this may be very important for us), and he is using the catalyst which will cause the actual reaction. I personally wouldn't call this titration....for he doesn't care what the pH is. I would call it a caustic reaction percentage.

When we titrate, we are looking for a pH change. We may be looking for a pH reaction which is not necessarily the exact reaction we need to be looking for (works, but not as efficient).

Paddy is watching for a reaction which will be duplicated with a larger batch of the same material (with a corrected amount of KOH/NaOH). Because of this, his methods may show to have a better efficiency rate.

When we titrate using the standard technique, we are not converting anything, but are looking for a pH change. pH may not necessarily directly correlate to the reaction (contaminates, different catalyst, etc). We are also using isopropyl, which may not work as well as we believe.

Would someone consider using a titration solution using methanol, instead of isopropyl?

We must remember with his titration method....even though he could be (if the titration ends up being very high) using a huge amount of methanol to find the correct titration, it is irrelevant. Methanol can be used in extreme surplus for it is the catalyst not the reagent (NaOH/KOH is the reagent).

For an example I was reading on another forum......about using a technique to find a titration without a pH indicator. The result was looking for which solution created the most glycerol. That is not true. The most efficient may not produce the most amount of glycerol (better efficiency may produce more biodiesel which would use some of that glycerol).

Have I lost my mind.....or could the above be true?

James L
 
Location: Central Alabama (Marion Junction) | Registered: February 20, 2010Reply With QuoteReport This Post
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Again, I think we are over-thinking this a bit. Excellent results have been obtained by just using a pump capable of turning over the whole batch in one minute. I hope to get back in the shop next week and do some small scale testing. Why not do a 1 liter batch? Use a mechanical stirrer or just shake it for 5 minutes?
 
Location: New Orleans | Registered: December 31, 2007Reply With QuoteReport This Post
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BT,

One of the things that I am not absolutely positive about though is how much pressure increase in the recirc. system drops flow rate and when the tank eductors are rated for tank mixing - does this tank mixing increase reflect 4-5 times the original none obstructed flow rate or the new reduced flow rate???

I believe it refers to the new constricted flow rate through the eductor. So using Murphy's pump as an example: with no eductor, ~80 gpm. Then add the eductor and hypothetically reduce flow rate by 50% to 40 gpm then the eductor could potentially increase mixing inside the tank to 160-200 gpm provided it has the motive force (pressure) necessary (70-80 psi).

Talking with Murphy - he doesn't really recommend eductors to be used with his pumps, since they aren't designed to generate pressure but instead are designed to maximize flow rate. Therefore the line pressure produced isn't anywhere near 70 psi and the tank mixing increase isn't anywhere near the 4-5 times number - in fact it is quite possible that the net effect is close to zero.

Having said this though it is important to recognize that eductor mixing produces a very different tank mixing than simple recirc mixing and in my opinion (for the biodiesl reaction) better...

GCG
 
Location: Michigan | Registered: May 08, 2007Reply With QuoteReport This Post
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GCG,

I know that jamesrl was only focusing on the smaller pumps like the HF. He did say (or someone did) that an eductor for Murphy's pumps were probably unnecessary.

James L
 
Location: Central Alabama (Marion Junction) | Registered: February 20, 2010Reply With QuoteReport This Post
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Fundamentally, eductors allow the use of smaller pumps.

The clearwater pumps are too small as evident by the fact that methoxide must be added slowly (or in stages) using venturi injection to obtain acceptable conversion. The addition of an eductor adds enough turbulence inside the tank to allow a fast dump of methoxide into the tank and still have good conversion.

When you use an eductor properly sized for the clearwater pump, there is an increase in operating head pressure of about 15-30 psi. This increase in pressure requires the use of all steel circulation plumbing.

If there is enough turbulence inside the tank to prevent the concentration of raw glycerin in the bottom of the tank, there is also enough turbulence inside the tank to allow for bulk addition of the methoxide. If there is enough turbulence inside the tank, it does not matter if the oil is added to the methoxide or if the methoxide is added to the oil. The end result will be the same.
 
Location: Cowboy Country | Registered: December 06, 2004Reply With QuoteReport This Post
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Rick,

Why the use of steel. Copper should easily withstand 15-30 psi of pressure. House hole water pressure is 60 psi (although it is cold).

James L
 
Location: Central Alabama (Marion Junction) | Registered: February 20, 2010Reply With QuoteReport This Post



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Fair enough

Has anyone tried to inject methoxide into the oil in 1 minute or less?
 
Location: New Orleans | Registered: December 31, 2007Reply With QuoteReport This Post
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J Long, Copper would work as long as all the solder joints were of good quality.

dennislarock, yes, injecting too fast through a venturi style injection system creates glop.
 
Location: Cowboy Country | Registered: December 06, 2004Reply With QuoteReport This Post
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