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GL's Eco-System processor

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March 20, 2007, 10:42 AM
GrahamLaming
GL's Eco-System processor
Hi Ant, hope you're keeping well.

That's a very good question - one I've not considered. I believe it drops all the glycerol, but I've not made a measure of residual glycerol after distilling off the methanol. There may well be some, but I don't know for sure.

One way to tell.... I'll let you know, with as precise an experiment as I can muster.


Rover 75 + Skoda Fabia on B100
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Bicycle on G100 12,000 miles p.a. ( http://uk.virginmoneygiving.com/GrahamLaming )
March 20, 2007, 11:42 AM
Chris Farley
Graham,
I have been experimenting with methanol recovery and filtering (in an attempt to dispense with the need to water-wash), but I have not had any appreciable amount of "soap" appear in my filter. I have been scared to use the bio without washing, because of this. It does seem to be a little more emulsion resistant, though.
I use KOH. Is this the reason for the missing soap?


'93 Chevy K3500 w/6.5 turbo, 4x4. 20k miles on bio and counting.
'02 Ford F350 4 Door Short-Bed w/7.3 Powerstroke. 15k miles on bio.
March 20, 2007, 12:12 PM
GrahamLaming
Hi Chris

KOH soap seems to slip thru filters easier than NaOH soap. It needs to be filtered gently.

Are you pumping biodiesel thru the filter, or letting it gravity strain?

KOH soap seems to form a fairly thin gel, and if you put enough pressure into your filter, you can find the soap gets squeezed through.

Perhaps try less pressure on the soap filter, and filter at as low a temperature as possible so it is not as soft.

Magnesol seems to successful in removing KOH soap.

I prefer to use NaOH because it can be filtered easier, and tends to drop soap to the bottom of the tank under gravity, so I don't even filter the top volume after it's settled a few days.

Bromophenol titration can tell you if the biodiesel is sufficiently soap free. It it a very useful titration indded.

Hope that helps, let us know how you get on with gentler filtering at lower temperature.


Rover 75 + Skoda Fabia on B100
http://www.graham-laming.com

Bicycle on G100 12,000 miles p.a. ( http://uk.virginmoneygiving.com/GrahamLaming )
March 21, 2007, 10:15 AM
Chris Farley
Ahhh....

.....so KOH soap = dawn dish detergent
...and NaOH soap = cascade dishwasher detergent

(I dont know if these are common brands in the UK, but I thought it was a great analogy!)

And, yes, I have been filtering at high temp and pressure. No wonder!


'93 Chevy K3500 w/6.5 turbo, 4x4. 20k miles on bio and counting.
'02 Ford F350 4 Door Short-Bed w/7.3 Powerstroke. 15k miles on bio.
March 21, 2007, 12:19 PM
fatkid
Hi Graham and other smarter folks than I!
Some of your technical expertise please?! My first attempt at a home-made venturi was less than successful. Instead of 'sucking' my venturi was 'blowing'. I tried it in both directions. My thoughts on this were my smaller side port had extended into the stream and should probably be pulled back and/or a smaller side port.
I was attempting to pound a 3/4" copper pipe down to 1/2" and my side port was 1/2".
March 21, 2007, 03:32 PM
GrahamLaming
Hi Fatkid

If you look down the tube you are blowing into, you shouldn't be able to see the side port. It should just look like a nice round hole.

If that fluid going down the tube can 'see' the side port before it gets there, it will head for it and go down it.

You need a shape something like this ...



The main flow goes in the left side, out the right side.

The suction port is at the bottom.

I placed the hole just where the tube sarts getting wider - JUUUUUST after the narrowest part.

It is a hole in the side, nothing is poking into the flow - like I say, surprise the flow, it shouldn't even know there's a side port till it gets there.

If you do it just before the narrowest part (too far to the left) it won't work well.

Hope that makes sense.

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


Rover 75 + Skoda Fabia on B100
http://www.graham-laming.com

Bicycle on G100 12,000 miles p.a. ( http://uk.virginmoneygiving.com/GrahamLaming )
March 21, 2007, 05:50 PM
jamesrl
Hi, I've made and tested my own venturi to the suggested design but with a small difference. It has 8 x 3mm holes around the throat which is 13mm and a jacket with a single 5/16 feed. the suction is incredible, haven't tried total lift yet but I expect 10 ft plus. See photo

This message has been edited. Last edited by: Shaun,
March 21, 2007, 05:54 PM
jamesrl
Forgot to mention my dual soon to be triple inline mixer another photo maybe two if I can make it work

This message has been edited. Last edited by: Shaun,
March 21, 2007, 05:57 PM
jamesrl
Couldn't do it in one so here's another, by the way the mixers are made from a single piece of tube.

This message has been edited. Last edited by: Shaun,
March 22, 2007, 02:12 AM
fatkid
Hi jamesrl;
[QUOTE]Originally posted by jamesrl:
...It has 8 3mm hole around the throat which is 13mm and a jacket with a single 5/16 feed. /QUOTE]

You wouldn't be able to have any pics of this thing disassembled would you?
March 22, 2007, 02:19 AM
fatkid
Graham,
Thanks, for the 'SCHHLUUUURPPPP' that was a good chuckle. I definitely had that designed wrong, so it needs to 'sneak' up on the port. Is your copper pipe there in the UK softer than on this side of the pond, I had a dickens of a time trying to form it?
Thanks for all of your tinkering.
March 22, 2007, 02:30 AM
ONADAY
quote:
Originally posted by jamesrl:
Hi, I've made and tested my own venturi to the suggested design but with a small difference. It has 8 3mm hole around the throat which is 13mm and a jacket with a single 5/16 feed. the suction is incredable, haven't tried total lift yet but I expect 10 ft plus. See photo


jamesrl.. a couple of comments .. I'm sure you mean a 8 mm hole? Does the tapered feed tube end at the larger tube or extend slightly into it?? It looks to me like more vacuum would be produced if you moved your feed tube closer to the end of the narrowd tube and angled your feed tube about 60 degrees instead of 90 degrees .. just my two bits worth...
March 22, 2007, 04:06 AM
GrahamLaming
Hi Jamesrl

Really neat! Which parts did you use for the jacket - that's exactly what I'd like to try.
How did you crimp the pipe in your mixer?

----------------

Hi fatkid,

The pipe here is pretty hard - there are several things to prepare yourself for when doing this ...

1. Be patient. The shape seems to take forever to start, but it does form faster as you progress - as the tube narrows, each hit has more effect.

2. Be gentle. Don't try and create a venturi shape in 10 enormous hits! Many medium force hits, where you can barely see the indent you've made, will ensure the shape develops evenly and without too much stress to your arm.

3. Concentrate on forming the narrowest part first, angling the tube against the anvil as in my video, and the shape will naturally form a venturi with one sharp taper, one smooth.


--------------------

Hi Onaday,

I think jamesrl has 8x 3mm diameter holes around the neck of the tube.

Hope that helps,


Rover 75 + Skoda Fabia on B100
http://www.graham-laming.com

Bicycle on G100 12,000 miles p.a. ( http://uk.virginmoneygiving.com/GrahamLaming )
March 22, 2007, 06:25 AM
jamesrl
Hi all,
Fisrt things fisrt, to make it clear, around the throat just and only just on the outlet side (long taper) there are 8 eqally spaced 3mm or 1/8 holes. The first attempt had 12 x 2mm, that worked well also.

For all those wishing to make a venturi, heat area to be worked to bright red with blow lamp, when that has been done quench in cold water this will soften the copper, it's called annealing, work the tube it will form very easily so be gentle with the blows. As you work the copper will get harder again, thats work hardening, so soften it again and carry on working. You can keep annealing as often as you wish but remember that if you anneal close to the finished shape the tube will be very soft.

Graham to answer your question, the jacket is made from an end feed 22mm coupling slide over the venturi and shaped in position. The inlet tube was fitted first using copper to copper brazing rods and drilled through after attachment. I hope that makes it clear.

Got to go now but back later with info on mixers

This message has been edited. Last edited by: jamesrl,
March 22, 2007, 09:10 AM
Logan Vilas
I've seen several venturi suction pumps and air amplifyers that were designed like this. has anyone tried it? I think the key to this is if you have flow through the system then it should never backup and push down the suction hole. it would probably be best installed with the outlet pointing down into your processor so unless you overfill the processor it should never go back down the suction tube.

for some reason my picture is not posting correctly when I looked at it. the inlet should have a tube moving completely past the suction port. for some reason the line on the bottom does not show up when I opened it.

now it's showing correctly

Logan Vilas


March 22, 2007, 10:08 AM
Cover
Just letting you guys know that know that a venturi pump can significantly reduce your pump flow rate because of the backpressure it creates.

This is due to the reduction of the pipe diameter in the throat (nozzle)

Graham:
Wouldn't it be possible to plump the suction from the venturi to the base of the methanol condensate tank to collect and mix back in methanol while processing. This system would then be come a reflux (or some thing to that name) reactor and you can process at higher temperatures or possible use even less methanol

By using a diverter valve system you could change the suction between the top or bottom of the tank depending of where you want to remove methanol of mix it back in.


"Learn from yesterday, live for today, hope for tomorrow. The important thing is not to stop questioning."
March 22, 2007, 11:42 AM
GrahamLaming
Hi Cover,

That's a very interesting suggestion - thanks.

I've not tried processing above 60C, so don't get much condensate during the period, but it would be interesting to see how the process time is affected by running say at 65C and returning condensate.

I have a sneaking feeling may not be feasible to go much hotter than that, because the vapourisation of the methanol will tend to keep the temperature down.

Here's an analogy...

Imagine trying to boil a kettle of water, and you want to get the temperature above boiling point - it's just not going to happen - unless you pressurise the system.

I would be very reluctant to pressurise my system, as it is not rated for running at more than a few psi.

There may also be an efficieny tradeoff, as you'd need to keep condensing vapour, and your condenser may lose heat energy to the environment.


The venturi should be fairly free flowing if well made, because although there is a restriction, is is not impeding flow by much at all whilst not pumping, and even when it is pumping, we are moving fairly low flow-rates.

I have hydrostatic indicators (manometers) on the test system, so I can see backpressure and so on.

Sounds wrong, you'd expect a narrowing from 22mm to 8mm to have an eneormous effect, but here's why it is less than you'd expect ...

We are not really blocking the pipe, we are gradually encouraging the flow to speed up in one section, and gradually then slowing it down.

'Gradually' is important - the tapers control the gradual acceleration and deceleration.

So the flow rate is not affected nearly as much as if we had a classical sudden restriction in the pipe, like from a valve.

A really good venturi mat reduce flow rate by only 10% or so.

The back pressure does increase when the venturi is sucking a flow of liquid or gas into it, but this is only during dosing and dewatering and distilling, and we can turn the suction flow rate down to quite low levels during these processes. The back pressure reduces as you reduce the speed of drawn-in material.

Best regards,


Rover 75 + Skoda Fabia on B100
http://www.graham-laming.com

Bicycle on G100 12,000 miles p.a. ( http://uk.virginmoneygiving.com/GrahamLaming )
March 22, 2007, 12:04 PM
Twenty4Seven
quote:
Originally posted by jamesrl:
Hi, I've made and tested my own venturi to the suggested design but with a small difference. It has 8 3mm hole around the throat which is 13mm and a jacket with a single 5/16 feed. the suction is incredable, haven't tried total lift yet but I expect 10 ft plus. See photo



Congratulations on a very tidy job - I wish I had the knack. My kitchen table is covered in the world's supply of reducers, T pieces and various offcuts of pipe as I try to figure a way to make a venturi without recourse to "copper bashing"

Cheers

Nick


Free collection of waste cooking oil in the Nottingahm area http://wastevegoil.co.uk
March 22, 2007, 01:00 PM
Cover
Your are so right Graham
It wouldn't make much sense to go over the boiling point of methanol if your not working with a presured reactor and the whole ventur setup wouldn't be need as it would be a closed system.

But there will always be vapour that can be reclaimed even at 65C. So if there is no point on going higher temps, there is always the possibility of using less methanol.


"Learn from yesterday, live for today, hope for tomorrow. The important thing is not to stop questioning."
March 22, 2007, 01:08 PM
duramadmax
Hi everyone. Been a long time lurker and have built my equipment (processor built like Graham's)but have not actually used it yet. I have been doing small batches. I am reading it right that you have done your 3/27 test before settling as stated in your writeup? I see others doing the test after settling. Please clarify.