Biodiesel Processor

[CURLY]

Hi everyone,

i'm sure this has been done to death, but i can never seem to find what i'm looking for with the search function!

does anyone have any 'blueprints' or diagrams etc on how to make a bio diesel processor for personal use?

i'm thinking of making my own and wanted to know basically what parts and tubs etc i'd need.

cheers in advance!

CURLY

[biodave]

Hi everyone,

i'm sure this has been done to death, but i can never seem to find what i'm looking for with the search function!

does anyone have any 'blueprints' or diagrams etc on how to make a bio diesel processor for personal use?

i'm thinking of making my own and wanted to know basically what parts and tubs etc i'd need.

cheers in advance!

CURLY

been there, done that, worn the t shirt and strongly recommend you don't but will if you insist

if you were going to race competitively off road, would you buy second hand bits here, there and everywhere and cobble them together and if you did would you expect to win anything at all? a proper biodiesel kit designed by someone who knows what they are doing will make much better quality biodiesel, with much higher yields, far fewer failures, use less chemicals and will save you far more money in the long run. Don't forget, if you do 10,000 miles a year in a disco you are likely to be buying 500 gallons of diesel at around £4.50 per gallon, that's well over £2000 (which is why I asume you are looking at biodiesel) Buy a decent assembled processor for £1,000 to £1,500 and you will get your money back in the first year and it will then last years and years.

But if you want to see what's in a system, try http://www.cleanercombustion.co.uk/evap_bioprocessor.html where they show a full system item by item and give advice on how to choose

all the best

biodave

[TheRecklessEngineer]

I don't think I've ever seen plans on this forum, but try this forum instead

Loads of info out there on the 'net. I've built several now from old hot water cylinders and domestic plumbing parts.

[Turbocharger]

Unless you've got a private supply of waste oil, I'd suggest you look closely at the price of buying the oil to use as feedstock. Bulk buy is 80/litre at the best rates, plus using £2k-worth of kit to turn it into biodiesel, or 103ppl for straight diesel with far fewer of the quality worries.

If you're doing it for environmental reasons, it's probably worth remembering that you're buying B5 at the pump and will be moving to B7 by September anyway.

If you run a chip shop and are only getting ~5p/litre as rebate for the waste oil, it makes sense.

I can speak with some authority; the Chipper bus is one of my projects in work.

[roguevogue]

Biodave and I are obviously at opposite ends of the scale, I make all the fuel I use in my Disco in a processor built from items from my local scrap yard, the only custom made bit is the reactor vessel itself which has a conical bottom, however, you can use a barrel inclined to allow the waste products to be seperated from the fuel.

You do not need to spend 2k on a plant and don't let anyone tell you that you do. True to say that a 2k setup will be prettier, cleaner and perhaps easier to use.

I use the recipe from Journey to Forever, which I find to be very successful.

You will need to find a supplier for chemicals etc. never mind building a processor.

[biodave]

We're not really different. I started 4 years ago with an old copper cylinder, inverted to get a conical base, I bought a small cheap pump and used bits and pieces of copper 22mm pipe lying around. I settled fuel in a 45 gallon steel drum, water washed, etc., etc. I used that for almost 2 years and made thousands of litres of biodiesel using recipes from Journey to Forever. Been there, done that. It all looked good and my cars ran on it. BUT ..... BUT .... I have moved on.

Biodiesel, by definition, is minimum 96.7% methyl esters, in other words, 96.7% of the oil you put into the processor must be changed into biodiesel. When I now test old samples of the biodiesel that I made with my old copper cylinder set up, I am ashamed to say I never actually got anywhere near that. Yes it looked good, nice and clear, and the cars ran on it, but I now know that what I was making was often as low as 60% Methyl Esters. My poorly made biodiesel contained up to 40% tri-glycerides, along with really harmful and damaging mono-glycerides, di-glycerides, soaps, excess caustic, and other assorted by-products of incomplete reaction (read how severely critical Journey to Forever is about purity). You would be better just adding 40% vegetable oil to fossil diesel, far less hassle and probably less damaging to your engine.

I now make biodiesel to European standards, with well over 98% conversion, in my new professionsl processor. What took sometimes as long as 4 hours I now do in 45 minutes. It is just so quick, efficient, effective and reliable. The fuel is good, pure and clean with no impurities. Before you say I'm a purist try this link

and you will see that I have run my Disco on 100% waste vegetable oil, straight from the chip shop, filtered and fed through a fuel pre-heater, and it ran well. But using any fuel for a few thousand miles is nothing compared to the 500,000 miles a diesel engine is good for.

I believe people looking to make biodiesel should be informed when they make their choice as to whether to use a home made system or purchase one. Having used both I would never, ever recommend anybody makes their own system unless they know exactly what they are doing.

sorry for the lengthy answer

Biodave

[biodave]

latest figures on ebay show waste oil 1000 litres at 38p per litre plus delivery and locally I can buy it for less than half that

also processors are advertised from £300 but a really good one is around £1K

you fill up a tank for £70 and give Gordon Brown and his crew £55+ in taxes if you like, it's a free world. I prefer to buy 5 tankfuls of waste veggie oil for less money and pay him nothing in duty or VAT, legally!

biodave

[GBMUD]

Whether one had made or bought a converter is academic I would have thought. As long as it is up to the job (and some people's home made hardware is far better than some bought kit!) then fuel quality (reaction % etc.) is about the quality of the chemical process not the price of the hardware. Doing proper titrations to make sure the right amount of lye/methanol goes in seems to be key.

As a matter of interest, where and how is the time saved with your current kit? Cutting a 4h process down to 45m is impressive, but where is the time saved? I assume the trans-esterification takes much the same time whatever?

Chris

[biodave]

Chris

I regularly made poor biodiesel with low percentage conversion, often in the 50% and 60% range (I'm ashamed now), even running the system for over 3 hours. I changed chemical suppliers believing they were poor quality, I changed just about everything I could think of, but the most dramatic change was when I changed the pump. The old one was 38 lpm (litres per minute) Tam 105, highly recommended on the web and most forums. I bought a 110 lpm monster. The throughput and the mixing are now what can only be described as ferocious. I now mix up my methoxide using 3.5 + titration value (X 1.4 for potassium), add it all at once to 150 litres WVO and react at 50C. After 45 minutes I turn it off, let it settle 10 minutes, then methanol test the biodiesel. Often it has already finished, sometimes, I know not why, it hasn't, so in that case I turn it back on for 15 minutes and repeat every 15 minutes until it has finished. I have never reacted longer than 1 hour 30 minutes with this pump. The last batch yesterday completely reacted after the first test at 45 minutes.

I personally believe that most people have a hugely undersized pump, meaning that the reaction is never properly agitated. People who realise it has not completely reacted (but not why) resort to adding extra caustic, using base rate of 4g or even 5g (Journey to Forever states 3.5 and I agree), or split adding the methoxide 80/20, or leave the reaction running 4 hours, or react at 60C. I don't believe any of this is necessary and I don't believe any of it results in a complete reaction. Why not? In simple terms, in theory I could heat my house by burning a single candle if I left it burning long enough. We all know it never happens. Likewise most people think if the reaction hasn't completed, just run it longer. I now don't believe it works.

I believe that an undersized pump never will complete the reaction no matter what you try to do. I believe it always leaves unused caustic, mono-glycerides, di-glycerides and tri-glycerides which will never water wash out in a month of Sundays, you just get an instant emulsion (a lot of Journey to Forever deals with emulsions and breaking them, although they do also state that if you make good biodiesel you can thrash it with a drill and paint stirrer and get almost instant separation, and I totally agree). Most people who have a problem making biodiesel try to gently wash it, even mist washing, to avoid that dreaded emulsion. Don't bother. Make good biodiesel instead.

Reaction time depends on good chemicals, but I've never actually bought bad ones. It depends on temp, I use 50C. It depends on reasonably de-watered oil. And it depends on good agitation. If you eliminate all the others, try a new pump.

Get a monster pump, thrash the mixture to death in less than an hour and sit back and watch it wash out like you've never seen before. I guarantee 2 things; a) it will make better biodiesel with higher conversion percentage in much shorter times; and B) if it doesn't, then at least you'll find out that you've made bad biodiesel after only an hour, saving you hours of wasted time.

Anyone putting together a kit on their own using their own design may not be aware of this. Any decent company should, although I still see reactors on ebay for £500 to £800 with a Tam 105 bolted to it. By the way, there's nothing wrong with the Tam, its a good pump, just undersized for a reactor pump. I now use mine for moving the finished biodiesel from storage tank to containers to car fuel tank, for which it is brilliant.

Sorry again for the lengthy reply

Biodave

[GBMUD]

Sorry again for the lengthy reply

Biodave

Dave

Just thorough!

So you use a pump to agitate the oil during reaction? I assume you pump out of the bottom and back into the top/side or vice versa? What is your opinion of a mechanical mixer - a motor driven blade rather like a plaster mixing paddle I am thinking. I have seen both systems used.

With the right plumbing, and a lot of valves, you could use one motor (and perhaps gravity) for all applications in a processor...

Do you still water wash? I was buying bio diesel locally from a professional producer but I, and another guy, started finding a problem with a very fine white powdery substance in the bio diesel. We put this down to the ion exchange tower that they were using to wash their fuel though they would never admit any problems existed - despite their suffering lots of blocked filters on their fuel pump.

Chris

[biodave]

Chris

I have never tried any other method. I run a big pump that sucks up the oil then mixes it while it is heating, then sucks up the methoxide and mixes it during the reaction, then, after settling and draining off the glycerine, it pumps the raw biodiesel into a settling tank from where it will be washed, used to water wash but I now use dry washing, usually Purolite (dearer to buy but lasts ages) or Eco2pure (cheaper, easier to get rid of (sawdust soaked in methanol and biodiesel!) but gets exhausted very quickly so more expensive per litre)

Have not looked at stirrers, but might.

The reaction time and efficiency depends on agitation, if you doubt it, try just pouring the methoxide into the hot oil and waiting. Nothing happens. The more vigorously you mix the quicker and more thorough the reaction (up to certain limits, obviously, you cannot convert more than about 99% no matter what you do)

The kit I use is on shown cleanercombustoion.co.uk products page and makes great biodiesel with little effort

let me know if you have info on mechanical stirring, I am always keen to learn

Good luck

Biodave

[white90]

Dave welcome

but please advise members that you are linked to the company you are talking about buying from so as not to appear to be advertising wares.

[biodave]

Sorry Tony

I am a director of Cleaner Combustion Ltd which supplies consultancy, surveys and tailor made biodiesel processors to local businesses within a 40 mile radius of Falmouth, so I could be seen to have a vested interest in promoting complete kits, but maybe my personal experience will help others understand that it is not for business reasons that I hold this belief.

I began over 4 years ago as a private motorist running on 100% wvo (twin tank) then 100% wvo (single tank) and began making biodiesel at the end of 2005. I began by making my own reactor out of bits I had knocking around and other bits I had to buy. The processor evolved over time, but at no time did my efforts result in running a biodiesel processor that could actually make biodiesel with a conversion efficiency of 95%. The stuff I made did go into my cars which appeared to run well, especially my Vauxhall Frontera B 2.2 TDi automatic Limited Edition. However, there were 2 hidden, but very serious problems with doing this.

According to HM Revenue and Customs for biodiesel to be biodiesel you need to have 96.7% conversion of oil to methyl esters. Below this the fuel you produce is not legally biodiesel, but is classed as a fuel substutute, and that is charged at the same rate of duty as the fuel it replaces, namely diesel where the fuel duty is 54p per litre. But, more important, you do not get the 2,500 litre duty free allowance. In other words, if you get stopped or raided at home (as I have been) and if the fuel is not 96.7% or more methyl esters (I was in the clear), you could be charged with duty evasion, which carries very serious penalties, or be made to back pay the appropriate duty.

More serious, is the quality of the fuel. I believed that having run my cars on 100% waste veggie oil, that any conversion to thin it down would be good news. But no! Breaking the initial bond of the tri-glyceride produces methyl esters (the bit that is biodiesel), but also mono-glycerides and di-glycerides which need to be further broken down. These are both very much more harmful (coking, gumming, erosion of components, etc) than burning tri-glycerides (veggie oil is nearly 100% tri-glycerides). And incomplete conversion also leaves glycerine, unreacted caustic, soaps and water that are especially harmful to engines. In plain English, making poor quality biodiesel does more damage than just bunging in cold veggie oil into the tank, which is not a good thing to do.

So, while anyone can put together a home made processor that makes a runny fuel that is called biodiesel, the vast majority are incapable of making biodiesel (96.7% and above conversion) putting you at odds with HMRC and maybe causing engine damage over a few thousand, or a few tens of thousands of miles, costing you far more than you have just saved. This lack of knowledge is why we formed the company just over 2 years ago.

For anyone who completely understands what they are doing, the chemical processes and the physics behind the reaction, please go for it, and I will offer designs and advice free of charge, as stated in my original posting on this subject. But if you are not an expert, I strongly recommend you save up and buy a decent processor ready built from a company who knows what they are doing (not us, by the way, we do not sell kits for mail order).

Sorry again for a long reply

Biodave