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My vegoil cleaning procedure and experiance using baking soda in the wash water.
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Water is the cheapest filter for wvo. Water removes food particles, salt, sugar, soap and water soluble acids. Water washing at least once before making bio-d would probably lower titration. For wvo converted vehicles, coarse filtration, water washing a few times, then drying should produce good clean oil.
 
Registered: September 26, 2005Reply With QuoteReport This Post
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Pretty much agree with all of that. Just to elaborate, the titration number change would likely be due to removing water soluable acids that can cause false readings in the "titration" test, other discussions (HERE and HERE) about reducing FFA's indicate you need some amount of caustic (baking soda, washing soda, lye) to reduce FFA's (That is my reason for adding the BS).

My single-step water/BS-washed oil certainly looks clean but I would still recommend some sort of filtering. I do eventually plug up 5 micron filters so it appears that my washed oil still has some amount of small particals in.

Other web info about filtering indicate that you can only see particals that are about 40 micron or larger so "clean looking" oil can still have a lot of tiny stuff in it.
 
Location: fisher,illinois,usa | Registered: June 03, 2003Reply With QuoteReport This Post
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Yeah, you're right, I forgot to mention a second filtration. Just in case the water missed some smaller particles, it would be good to fine filter through a 5 micron (or less) filter. It makes me wonder about some of these horror stories about really bad oil that's really acidic. What I wonder is how much of the acid is water soluble verses oil soluble? Would water wash prior to reaction be worthwhile? I mean, it was already said that water would remove soaps, salts and sugars (good thing), but I've heard that cleaner oil is more susceptable to emulsions (bad thing). I guess the food particles keep the soap tied up a bit reducing the emulsion effect. To be honest, I don't think emulsions are that scary. Girl Mark mentioned using salts (other than sodium bicarbonate)to break things up. Some guys use a little flour to deprive the soap of enough water to stay emulsified, (or liquified) causing it to precipitate out of solution. One guy I know throws in a little vinegar, thereby neutralizing the lye residue that bonded with the water which is what caused the soapy emulsion in the first place. I know that I'm assuming that the presence of water prevented traces of unreacted lye from contacting traces of unreacted oil forming a soapy emulsion. He doesn't often get emulsions, but when he does, a bit of vinegar breaks it up quick. This would seem to support the theory that many emulsions are caused by water. That's why I suggested water washing the wvo to remove salts, soaps, sugar and food bits. I know that will add water to the oil, but it will not only save filters , but should also accurize titration tests before reaction. Just remember to dewater after water washing, but before reaction. It's all about control. Getting the oil as clean possible should straighten up the reacion. Remember one of the basic principals of applied chemistry? G.I.G.O. It stands for garbage in-garbage out. Big companies are making big money charging cities a large fee to clean brown grease out of the sewers. Then they make ASTM grade bio-d out of a free feedstock. Surely, if big corporations can make decent product from sewer sludge, then we can make at least as good a product from yellow grease. They have every advantage money can buy (teams of proffessionals with every gadget available). We have common sense, this forum and time (they are racing each other). G.I.G.O.
 
Registered: September 26, 2005Reply With QuoteReport This Post
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I read this thread rather quickly, but didn't see anyone mention that 'acidic' oil, and oil with high 'free fatty acides' are two different things. Acidic oil implies low pH, usually also implying water or water soluble items in your oil, which might be washed out. Free fatty acids are usually usually identified through titration, and don't wash out, which is why people make biodiesel with a catalytic reaction rather than by washing.
Ben
 
Registered: June 23, 2005Reply With QuoteReport This Post
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Ben -- True enough, but acid is acid, apparently high FFA's will do damage to metal (all official "oil directly as fuel" info that I have read recommend FFA titrations of 2 or less). For those of us that are using the oil directly as fuel the easiest way to reduce the FFA content is to use a caustic with water to convert the FFA's into soap, the soap WILL wash out of the oil. Check back through this discussion for links to FFA reduction discussions (last post on page 2) using baking soda or washing soda.
 
Location: fisher,illinois,usa | Registered: June 03, 2003Reply With QuoteReport This Post
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Tim..I believe that this is incorrect.
I have never seen any evidence that Free Fatty Acids are corrosive. Water soluble acids definately are though.

Other than corrosion I can't imagine what damage FFAs might do?

Titration is done on WVO in order to determine how much the methoxide should be provided to neutralize the effects of FFA levels on the transesterification process so it does not stop before the WVO being processes has completed its tranformation to biodiesel.

Do you have any links to info on damage that FFAs might do to a fuel system?

quote:
Originally posted by Tim c cook:
Ben -- True enough, but acid is acid, apparently high FFA's will do damage to metal (all official "oil directly as fuel" info that I have read recommend FFA titrations of 2 or less). For those of us that are using the oil directly as fuel the easiest way to reduce the FFA content is to use a caustic with water to convert the FFA's into soap, the soap WILL wash out of the oil. Check back through this discussion for links to FFA reduction discussions (last post on page 2) using baking soda or washing soda.
 
Location: Central MN..Brrrrrr! | Registered: November 06, 2001Reply With QuoteReport This Post



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Hi Tim:

Just a few thoughts:

Quote(Posted 18 June 2006 05:24 PM): "I also have sensed a bit of damage to my injection pump over the last couple years, the truck does not start on the very first compression stroke like it used to with petro diesel, it does start on the first compression stroke with a somewhat thicker blend, could be a lot of reasons but one could be that the IP has more clearance than it used to. This has happened over only the last couple of years so it has occured faster than I would attribute to normal wear, suspect it is a bit of acid damage. I would rather be safe than sorry. ..."


-- The IP does not build compression in the cylinder. The rings, wripe rings(or oil rings), and clyinder/piston clearance - all contribute to your compression. Thus, low compression poor staring, high compression good starting. The IP only pressurizes the fuel too allow the injectors to have a good spray pattern. If the engine runs good after startup, then you have good spray pattern. IP have considerable excess pressure to supply the injectors, even after long life. Starting better with thicker fuel, is also a sign of poor compression in the cylinder. Since, thicker fuel would help to seal the rings - thus giving better compression -> therefore better start ups.

-- I have followed a number of your posts. If I have this correctly, you don't heat your blends(not mods to the car). Not much studies out there with blends over B30. But with 100% SVO, studies have shown that you need mimimun 150F injection temperatures to stop cylinder damage(mostly coking). Coking damage can give lower compression as a first sign. With you running 50% WVO, that might cause problems. There are a number of studies/charts posted showing the blends needed for B100 mixed with diesel and/or kerosene to elimate clouding. SVO blending is not studied well yet. Just a thought.

-- I agree with Dana, I have not seen any posts or studies that indicate normal levels of FFA in SVO will harm the engine. Of coarse, super high FFA (like 30-50%) might be a different story. Most WVO is under 10% FFA. As long as all particles bigger than 5 microns and all water is removed, it will burn just fine in the engine.

-- Any BS left in your oil after washing, will invalidate your titration. Excessive water will throw it off also, so it would have to be dried first.

-- Washing in biodiesel production is much different from your water/BS washing of SVO. In Biodiesel production, many washing cycles are required to remove soap, and residual chemicals(mostly NaOH or Koh, Methanol, salts, and acids). Only water soluble residual chemicals can be removed by washing with water, hardwater created salts for example are not removed. The biodiesel is so much thinner, so water will mix easy and separate quickly. I don't think that the mixing you are doing once, is removing that much soap and other inpurities. Your data certainly shows that the svo is much clearer afterwards, which gives you longer filter life. BS does reduce FFA, and that will reduce the viscosity of the oil, thus allowing better settling.

With all the time your processing requires (like 2-4 weeks per barrel + your time). I know that I have processed really curdie oil, titrates at about 10-12% FFA - with lots of water, soaps, detergents, and crap, etc. Using just stardard heat(~150F), settle for 24 hours in insulated tank, drain off bottom settled crap+water, filter, then set in barrel for 2 weeks gives perfectly clear oil. That last 2 weeks will settle 3-4 inches of more crap in the bottom of the barrel, even though the oil was very clear going in. I then draw off from above 6 inches. With only about 1/2 hour of my time per barrel.

Not putting anybody down, just wondering if you are obtaining the same results with alot more work.


86 MB 300SDL
05 Jeep Liberty CRD
 
Location: Mechanicsville, MD | Registered: March 26, 2006Reply With QuoteReport This Post
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Hello Jimsveggie, Tim & Dana,

I've been reading a lot about this blending and making bio diesel stuffs.I decided what if I combine the two? Only using 10% Blending of WVO to ordinary petroleum diesel.

Recently I got very high FFA waste coconut oil 44%FFA. I boiled it around 150C to remove water, then when temp dropped to 85C I put activated carbon and spent clay to bleach it and hopefully lessen the FFA. After wards, I filtered it using ordinary filter paper.

I thinned the oil with 10% Methanol, and added 1% bio diesel. Now I got what I thought will be a good blending material to our petroleum diesel. I poured in around 2 liters of this mixture simoultaneously with 20 liters of petroleum diesel at a 10% blend.

The vehicle ran for several days and then it coked and stopped. We cleaned the fuel line and removed the blended svo/bio diesel. When we returned to straight petroleum diesel the engine went back to normal.

Does this blending really worked? I thought just 10% will do no harm? I even added only 1% bio diesel>>> What have I done wrong? The temperature in our area is 27C so the fuel should stay liquid>>>

Please advice..

rasza



I
 
Location: Philippines | Registered: July 12, 2006Reply With QuoteReport This Post
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JimmsVeggie -- Thicker fuel starting better than thin fuel in a worn IP -- My problem is not CYLINDER compression but Injection pump compression. What I was trying to convay is that the IP internal pistons are moving very slowly when being cranked by the engines starter, any excess clearance in the IP pistons will allow the thinner diesel to leak past them much more than with a thicker veg blend. since the IP pistons are moving so slowly while being cranked by the starter it takes a very small amount of leakage to affect the pressure they make in the injector supply lines, low pressure here will likely cause a poor fuel spray pattern into the cold cylinder, poor pattern and cold cylinder will likely cause a bit of harder starting, once the engine is running the IP pistons are moving at such a high speed there is little time for the fuel to leak past them so even thin fuel will make high pressures in the lines.

Filtering -- We disagree here - I dought your oil is nearly as clean as mine if you have several inches of crud in the barrel after a couple of weeks. I have oil that is well over 2 years old, nothing has settled to the bottom. If you can get away with it you are lucky, I can not, my methods of filtering have been developed out of nescessity, I have not had a plugged filter from crud in the last couple of years, Gelled oil is a different story but I have only had one of those last winter and the temps were 17 deg f, sort of expect that without heat.

No evidance that high FFA's are bad -- True, not much info available, I keep looking for info on this myself. Personally, I suspect less acid is better than more acid, acid is acid, it will attack metal. I DO find referances from those that should know (european gov testing etc) that recommend oil as fuel should not titrate to more than 2, works for me. Read through other high-FFA discussions here, here, or here.

Time -- It does not take any more of my time for my oil to settle than it takes of your time for your oil to settle, settling is done unattended so not a problem.


rasza -- Need a bit more info about your problem before it can be diagnosed. You mentioned "cleaning the fuel line", this sounds like a problem caused by either inadiquate filtering allowing the clay or carbon additive to not be removed from the fuel -or- some portion of the high FFA palm oil gelled, I have read that palm oil can easily be solid at ambient temps but have no experiance with it my self. In a blend it is possible for any one of the blended components to come out of solution and drop to the bottom of the fuel tank if the fuel temperature drops below the point needed for that particular fuel component to stay liquid, I have had this problem with animal fat. Once fat (or hydrogenated oil or whatever) turns solid it will coat a fuel filter with a very thin layer of lardlike stuff, that can be enough to stop the fuel from flowing through the filter. I have had to drop my fuel tank a couple of times because of fat clogging the fuel pickup screen, put in a much courser screen the last time.
 
Location: fisher,illinois,usa | Registered: June 03, 2003Reply With QuoteReport This Post
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quote:
acid is acid, it will attack metal.


Misconception...Free Fatty Acids are very different from water soluble acids.

Welcome to the Forum Rasza,
Fewer people have done Research and Development on blending than on heated strait VO conversion. So there is less info on this to base any conclusions on.

There are few if any on this forums that have blended waste coconut oil. I have had some experience using it but not in a blend. And I am unaware of any info of blends of methanol, biodiesel, and coconut oil. You may be the only one experimenting wit this.

Your problem may be as simple as chunks of solidified coconut oil clogging lines or filters...but any sugestions I provide will be pretty much speculation.

I suggest starting with a very low % of cocnut oil to solvent and increasing the cocnut oil % each tankful until you experience problems. This may provide more info to you to determine more closely what the problem is preventing smooth operation of the engine.

I also suggest having a comprression test done now so you can compare it to later compression test values. Even if you can get a diesel to RUN on a particular blend if it shows a lower compression reading at a laer date it probably indicates that there are other issues you need to address for long term reliability on that blend.
 
Location: Central MN..Brrrrrr! | Registered: November 06, 2001Reply With QuoteReport This Post
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Hi, I've been reading this forum for several months now before my first post. Thanks for all the invaluable experience you've imparted! I've got 6-7000 miles on my car now with wvo-10% kero, currently. I settle with 10% water for 2-3 weeks,pour the "clean looking" oil into a drum, heat the drum with a 1000 watt heater element for 24 hours (approx 250-270 degrees in top 12 inches, around 200 degrees at bottom), filter through 1 micron filter for 6-8 hours while it's hot then transfer to my "holding barrel" that I use from. This barrel is a plastic barrel tipped bottom down about 10 degrees with a hose bib screwed into it(this whole set-up in elevated off the floor 2 feet). The oil always sets 5-7 days before being used and I drain some from the bottom-most point of the barrel (a screw hole) check for settling. I frypan test and usually end up with no bubbles, only what I believe to be convection currents moving in the oil. My question pointed at this thread is- What effect on this discussion will the "spinner centrifuge" have? I bought plans and am beginning the building process. Thanks, ben
 
Location: ST LOUIS | Registered: June 17, 2006Reply With QuoteReport This Post
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mist wash, drain the free water, heat to 100 degrees and centrifuge on its way to your holding tank. (I hope) Big Grin


Though your argument is very clever, I don't think it will lead to the results you desire. gandhi
 
Location: iowa | Registered: December 19, 2005Reply With QuoteReport This Post



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Tim c cook, are you still using baking soda in your WVO filtering process? Any new findings?


S. Caxambu
 
Registered: August 11, 2005Reply With QuoteReport This Post
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Yes, still adding one pound of baking soda into a cubee of clean water, water/BS goes into the barrel first and then fill the barrel with newly collected veg, don't even bother to run the oil through a windowscreen any more, straight from the vac collection tank into the wash/settling barrel. stir it up well, turn on the heat, let settle for at least a week, turn off the heat over the last couple days so any really high-meltpoint fats have a chance to solidify and drop to the bottom of the barrel, move the mostly clean top oil into the filtering barrel, let the oil settle over night so the bulk of any free water drops to the bottom of the barrel, drain off a bit of fluid from the very bottom of the filtering barrel just in case I did pump a bit of water into this barrel, turn the heat back on and start circulating through the filters, also start circulating this oil through the flash evaporator at the same time, come back a couple days later and move the now clean dry oil off into storage.

I added a window screen strainer to the end of the intake hose used to move the oil from the wash/settling barrel over into the filter barrel, this keeps the settled chunks from clogging up the gear pump. I stop transfering the oil just before I hit the crud/water layer at the bottom of the settling barrel, the remainder of this nasty mix of solidified fats/oil/water/soap gets pumped back into empty cubees and goes off to the landfill, I use a garden hose and hard spray to wash out the very bottom of the barrel, the crud from this wash biodegrades in a few days after being dumped on my brush/burn pile.

I recently had to replace the 1.8 G/M, 12 volt, Shurflo RV pump that I use to circulate the warm oil through the filtering setup , amazed it lasted this long, I have used this pump extensively for about 5 years moving oil in general and it has been used exclusivly on the filtering setup now for about 2 years running continuously for 3-4 days at a time circulating 100 deg f oil. It has run this way almost weely. Wore it out pretty much completely, one internal rubber valve had a 1/4 inch hole in the center that caused the pump to stop making pressure (replacable), the wierd off-center off-angle excentric cam that is the mechanical heart of the pump had been warn down to the point it was no longer very excentric or off-angled so it did not move the plastic pistons hardly at all (have not yet found this part to be available seperatly), the electric motor still runs but I need to clean congealed oil out of the brushes to get it running correctly again. Not bad for a $60.00 pump.
 
Location: fisher,illinois,usa | Registered: June 03, 2003Reply With QuoteReport This Post
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Hello All,

I'm new to this forum and have been reading your posts with some interest. I think I have some experience that backs up Tim c cook's comments regarding worn IPs.

I've been working with a local mennonite farmer who has been burning WVO in a 350HP diesel genset for over 2 years. In that time, he has replaced 3 IPs and 4 sets of injectors. (it might be more, I've lost count) He burns about 5 gallons per hour and runs the genset about 10 hours a day. He uses a majority of the 3 phase power he generates to run his woodworking shop and runs his meter backwards with the rest. He uses the waste heat from the engine to process his oil and heat his building in winter. Here's a little history for those who are interested:

He began by collecting WVO from 14 restarants, heating it with the coolant from the engine and running it through a screen door. (yes, he actually used a real screen door) Then he'd let it settle for 12 hours and take the oil off the top to use directly in his engine. No additional filtering, no dewatering.

I met him after he'd replaced his first injection pump. One day, his engine just stopped working and he had no idea why? This seemed like an interesting problem and he asked me if I might help.

To make this long story a little shorter, it turned out he was switching from preheated WVO to cold diesel every night and we'd just had a really cold spell. The cold diesel caused the IP to seize. He replaced the IP and we re-plumbed the system so that everything was properly heated to 170F before hitting the IP and things worked well for 800 hours.

After that, we noticed that the engine became harder to start on diesel and would actually start best on cold WVO. (sound familiar Tim?) We were confused so I hired a diesel mechanic to pull the injectors. He found 8 of the worst injectors he ever saw. He brought his injector tester and these injectors leaked more than any he had ever seen on tractors with thousands and thousands of hours on them. We replaced the injectors and the starting situation improved somewhat.

We began filtering the WVO through filters down to 1 micron and I built a "dryer tank" from a 300 gallon stainless milk cooler. We'd heat the oil to 220F for 3 hours and then let it sit at 140F overnight. 500 hours later the same starting problem resurfaced and so we brought the mechanic back. Again, the injectors were toast but this time we had to replace the IP to get things right. Later analysis by the local company that does IP repair indicated both worn and corroded IP and injectors.

We attributed this to the time he continued to run the engine while we built the dewatering tank and filtering system. We were going to be fine from now on, right?

Well, this long tale gets worse. 700 hours later, he blew a hole through the side of the engine. John Deere said something in the IP failed and messed up the timing. Regardless, there went another IP and the engine required a short block replacement.

The supplier of the genset gave this fellow a new genset to use while they repaired the old one. (I use the term "gave" loosely) We now had a new engine to mess up and this would be the best test ever! We'd finally see if this WVO was causing all these problems.

Well, you've probably already guessed that some 800 hours later, the same symptoms returned, poor starting on diesel. Back came the mechanic and once again, the injectors needed replacing. We assumed the IP was next so I decided to pull it and get it checked out. This time, we didn't seem to have any obvious wear issues, just a dull grey corrosion on both the IP and injectors. (By wear issues, I mean visible scoring. We did get wear by means of corrosion)

Time to get more scientific. I felt sure that the oil coming out of the dryer was dry since I had tested it using the pan technique you guys talk about. I actually calculated that my friends oil had over 0.5% water after initial settling (before drying) that couldn't even be seen. The oil looked amber and clean. After drying, I titrated it and was shocked by what I found. It titrated to 10.5g of NaOH! I'm now just beginning to test the oil before we dry it to see if we're causing more FFA to form with our drying technique.

I immediately made a list of all the restaurants he collected from and vowed never to eat there again, just in case!

At this point, I'm experimenting with acid neutralizing. I'm interested in the posts where you talk about the effects of FFAs as corrosive agents. I had always assumed (oh D!@#, there's that word again!) that acid meant acid being defined as the presence of hydroxyl ions. Why should it matter where they come from? The addition of water would likely make them more effective at corroding so shouldn't they all be removed? Are there any chemists out there?

My first experiments with deacidification have yielded large amounts of stuff that looks like a McDonald's Chocolate Shake. Here's what I've done:

I titrated the oil and then dissolved that amount of NaOH in 40mL of water. I'm doing 1L test batches. I then mix this water/NaOH mixture into the oil and voila, milk shake! Maybe I'm mixing too roughly?

This post started with my wanting to comment on Tim c cook's issue and has turned into a cry for help. Any input would be appreciated.
 
Registered: June 30, 2007Reply With QuoteReport This Post
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Welcome Captain Canuk --

I know Dana does not agree, but I still think acid is acid, FFA or not, your recent experiance would seem to reinforce my opinion, baking soda is cheap insurance just in case I am correct. I can't find the link now but I read through one European testing document that stated they found etching when using high FFA oil and recomended the oil not test higher than 2, Don't know just what test they were using to get there number of "2".

There are several past discussions about lye or caustic stripping,
here is one, here is another, another.

The lye and water in your test are intended to turn all the FFA's into soap so I am not surprised at the chocolate milk result. I have not read through the "lye stripping or caustic reduction of FFA's" posts for a while but I think they indicated the soap settled over night leaving clean oil on top, don't remember for sure, but the soap should eventually settle. I add a bit of houshold flour to the oil when the emulsion does not seperate, the flour absorbes enough of the water that it somehow allows the soap to become more concentrated and heavier so it falls to the bottom, takes a couple days using 4 cups of flour well-stirred into 50 gallons of oil but it has worked every time on probably a dozen barrels of oil emulsions. The flour settles to the bottom along with all the other soap and crud.

water settling -- A good bit of my oil collection from a new place has caused me to pump a lot of settled water over into my filtering barrel, however they are using the oil it is causing my cleaning water to look just like the oil, I assume the water is leaching out soy sauce or something, anyway, I am finding that I have to let the oil cool well below your 140 degrees f before it will release the bulk of the water. The thermostats on my settling barrels are set to 100 deg f, this is still way too warm for the oil to release all the water. I now turn my settling barrel heaters off at least a full day before I transfer the oil. This does 2 things, the oil gets thick enough when cool that I can better see when I reach the water level. By the oil being cooled in the settling barrel it drops most of its water there, I leave the oil to cool and settle over another night in the filtering barrel, then drain from the vary bottom of the barrel before starting the circulation pump. I usually get another quart to half gallon of water from the bottom of this barrel after the additional overnight cooling/settling, the overnight temps are in the high 60's f here now and the oil is pretty close to that temp.

I tried only cooling over night but the oil was still up in the high 80's after only that length of time due to the insulation of the filter barrel, I ended up with the bottom of my filter housings being full of water after circulating for 2 days and I was still getting water vapor from the flash evaporator as the oil kept picking up this filter housing water every time it got passed back through the filters. By doing the extra cooling and draining I don't have enough water in the oil to end up in the filter housings.
The oil gets circulated through the flash evaporator along with the filters for another couple days, tests absolutely dry by then using the hot pan test. (The flash evaporator discussion is here)

I intend to shift over to a Dieselcraft centrifuge for filtering/dewatering some time in the future, collecting parts and money. It has proven itself to do the job in only a few hours instead of my 2-3 week process, just can't argue with success like it is showing, it can also be done as a mobile setup. Since my electicity rate jumped by 40% at the first of the year the centrifuge will save a good bit on my electric bill by not having to run heaters for the extra several days.

The Dieselcraft centrifuge discussion is HERE, it is extensive but well worth the read. The top of the first page has a link to a much condensed explination of the progress and results achieved during all the testing.

You can use the "find" button at the top of any page and search both forums with words like "FFA reduction, lye stripping, caustic stripping, baking soda, washing soda" etc. there have been more discussions about this than just the ones I show links to.
 
Location: fisher,illinois,usa | Registered: June 03, 2003Reply With QuoteReport This Post
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This may be of interest. It is from the Journal Article in Renewable Energy 28 (2003) 939-948 Some fatty acids used for latent heat storage:.

quote:
The present study includes thermal stability of some fatty acids as phase change materials
(PCMs). The selected fatty acids were stearic, palmitic, myristic and lauric acid with melting
temperatures between 40–63°C and industrial-grade with 90–95 % purity.

quote:
From the gravimetric and metallographic corrosion tests results, it can be concluded
that stainless steel (SS 304L) with chromium oxide (Cr2O3) surface layer and
aluminium (Al) metals with aluminium oxide (Al2O3) layer surface are essentially
compatible with the investigated fatty acids. Carbon steel (Steel C20) and Copper
(Cu) metals as storage container materials are preferantially compatible.


quote:
Table 6
Corrosion effects observed on the surface of metal samples by metallografic examination
Stearic Acid Palmitic Acid Myristic Acid Lauric Acid
SS 304 L Resistant Fig. 3(c)(d) Resistant Resistant Resistant
Steel C20 Resistant Slightly corroded Slightly corroded Fig. Resistant
3(g)(h)
Al Resistant Resistant Resistant Fig. 3(e)(f) Resistant
Cu Slightly corroded Fig. Slightly corroded Slightly corroded Slightly corroded
3(a)(b)


quote:
Table 5
Corrosion results obtained by gravimetric anlysis after 910 thermal cycles
Stearic Acid Palmitic Acid Myristic Acid Lauric Acid
Metal mass loss Corrosion mass loss Corrosion mass loss Corrosion mass loss Corrosion
sample (mg/cm2) rate (mg/cm2) rate (mg/cm2) rate (mg/cm2) rate
(mg/day) (mg/day) (mg/day) (mg/day)
SS 304L 0.425 4.7 10-4 0.333 3.7 10-4 0.254 2.8 10-4 0.291 3.2 10-4
Steel 9.662 1.0 10-2 28.770 3.1 10-2 44.620 4.9 10-2 14.027 1.5 10-2
C20
Al 0.654 7.1 10-4 0.909 10. 10-4 1.243 13.6 10-4 0.650 7.1 10-4
Cu 31.416 3.4 10-2 1.070 0.1 10-2 15.437 1.6 10-2 15.232 1.7 10-2
 
Location: Perth | Registered: April 17, 2007Reply With QuoteReport This Post
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Hi TroyH. That's very interesting info you posted. Got a link or did you type it out from a physical (non electric) published source? Hopefully, it will be available for everyone to assess and lead to a solid conclusion.

Thanks, man.
 
Registered: September 26, 2005Reply With QuoteReport This Post



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bump
 
Registered: September 26, 2005Reply With QuoteReport This Post
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sorry mate, I just noticed this and your pm. I'm pretty sure I downloaded it. I don't think I should post it on the forum, but if you pm me your email I'd be happy to email it to you.
Cheers,
Triy
 
Location: Perth | Registered: April 17, 2007Reply With QuoteReport This Post
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