Biopowered - vegetable oil and biodiesel forum
Biodiesel => Biodiesel equipment => Topic started by: Bio-boy on April 25, 2015, 10:01:49 AM
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In the process of building a bigger processor and would like some advice on what pump would be suitable.
Here is my tank:
http://www.tanks-direct.co.uk/900_litre_water_tanks/900_litre_biodiesel_tank
and this is the pump i've been thinking of purchasing but unsure of which model would be suitable:
http://www.oilybits.com/pumps-for-liquids-/ebara-cdx-fully-stainless-steel-centrifugal-pumps.html
I'm thinking the CDXHm 90/10 with a flow rate of 110LPM.
I will be using 1" piping and fittings with the intention of processing batches of 600L. Could someone with the knowledge please provide advice?
Many thanks.
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You've not linked the pump bio boy....you've linked the plastic tank twice.
If you can I would try and find a pump with a 1.5" inlet and outlet to match the cone outlet on the tank. If you cant do that then at least have the same OD pipe as the pump you select. I have 1 1/4" pipework as that's what my lowara is.
I'm sure you'll be careful but this is good advice that anybody will give you regarding plastic tanks. Don't overtighten the emersion when you fit it. The socket in that vessel is the weakest point.
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I have now altered the link. Please view.
I was going to reduce the outlet on the tank to 1" using one of these:
http://www.oilybits.com/fittings-threaded-/nipples-hex-reducing/316-stainless-reducing-hex-nipple.html
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I see you've amended your post. Just be aware of the "safe operating temperature" on that tank. Considering the batch size and the pump it may be worth buying a couple of eductors to help in the process.
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What is an eductor?
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This is a devise mounted inside the processor operating on the venturi principal and driven by the existing pump. It creates a turbulent circulation within the tank and significantly reduces processing times.
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Where can I get one from?
Are they submerged under the surface of the WVO???
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Where can I get one from?
You can get them from Uberveg on this forum of the VOD but they should be matched to the pump flow rate or you could ask Jamesrl on here if he'll make them for you. Jims are custom made whereas Uberveg's are bought in and are made from a bio compatable plastic.
This is Uberveg's website his stuff is on there somewhere:
www.oxfordwastecookingoil.co.uk
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Are they submerged under the surface of the WVO???
Ideally submerged a couple of inces below the surface of the WVO and methoxide mixing level
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You stated to fit 2 eductors. Would this be done via a tee on entry to the tank with then 2 feeds one to each eductor?
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Yeah...tee off from your main pipework. You'll need a valve to stop the flow from that and divert to your eductor matrix.
Jamesrl is probably the best guy to talk to regarding position and best fit for eductors. Apparantly he runs 3 eductors in his processor. Others just run one. I think HC used 10 but that was an industrial process.
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It is perhaps worth mentioning that, in a domestic environment, you are only allowed to process a limited amount of oil at one time - I believe it is 250 litres.
Nick
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Nick, I believe that restriction was rescinded a while back. But all the same, Bio-boy, you're planning a massive processor if it's for domestic production. Just 4 full batches will take you over your 2500 ltr per year allowance.
Also, although many folks use plastic processors, they are certainly not to be recommended ... see pictures on the wiki.
My plant, although far from perfect, uses a 80 ltr/min pump on an 80 ltr batch size (but with no eductor) and I recon the combination is about right for quick conversion. If you scale that up, for a 600ltr batch you'd be looking at an enormous pump, probably needing a 3ph supply.
As for pipe work I use a 28mm suction and 22mm discharge, I recon 1" pipe work on a plant the size you propose will be woefully inadequate.
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Nick, I believe that restriction was rescinded a while back. But all the same, Bio-boy, you're planning a massive processor if it's for domestic production. Just 4 full batches will take you over your 2500 ltr per year allowance.
Also, although many folks use plastic processors, they are certainly not to be recommended ... see pictures on the wiki.
My plant, although far from perfect, uses a 80 ltr/min pump on an 80 ltr batch size (but with no eductor) and I recon the combination is about right for quick conversion. If you scale that up, for a 600ltr batch you'd be looking at an enormous pump, probably needing a 3ph supply.
As for pipe work I use a 28mm suction and 22mm discharge, I recon 1" pipe work on a plant the size you propose will be woefully inadequate.
I am listening to what you are saying. I plan to up the pipework to 1.5". As for the pump I know someone who uses a 110LPM pump to good effect on similar batch sizes so will stick to a similar output. I don't plan to make more than 2500L I just plan to make batches less often freeing up time in what is a quite busy having a young family.
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As for pipe work I use a 28mm suction and 22mm discharge, I recon 1" pipe work on a plant the size you propose will be woefully inadequate.
Eh?
1" is the ID, whilst 28mm is the OD. (28 - 25.4) / 2 = 1.3mm which, surely, isnt too far the wall thickness?
Am i missing somthing?
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As for pipe work I use a 28mm suction and 22mm discharge, I recon 1" pipe work on a plant the size you propose will be woefully inadequate.
Eh?
1" is the ID, whilst 28mm is the OD. (28 - 25.4) / 2 = 1.3mm which, surely, isnt too far the wall thickness?
Am i missing somthing?
28mm OD = 26mm ID, on an 80 ltr/min pump ... on a pump of considerably higher flow however, 25 mm, in my humble opinion will be too small.
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The pump has 1" BSP outlets so surely it is designed to flow 110LPM through that Dia pipework???
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Which would be the better tank out of these two??? One is made from LDPE the other HDPE.
http://www.oilybits.com/conical-tanks/conical-food-grade-ldpe-polyethylene-tank-800-litre-with-stand.html
or
http://www.tanks-direct.co.uk/900_litre_water_tanks/900_litre_biodiesel_tank
Thanks
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Hi bio bill I would say the hdpe would be a much better tank I work with pe and the ldpe is much softer
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Hi bio bill I would say the hdpe would be a much better tank I work with pe and the ldpe is much softer
Thanks Dolphin.
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im not sure here as I don't do bio, im a veg runner, but isn't 55c not hot enough for reaction/dewater/demeth ? that's all a hdpe tank can handle...
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im not sure here as I don't do bio, im a veg runner, but isn't 55c not hot enough for reaction/dewater/demeth ? that's all a hdpe tank can handle...
...which is why I said what I said in post 4 of this thread.
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The pump has 1" BSP outlets so surely it is designed to flow 110LPM through that Dia pipework???
I think it rather depends on the pressure the pump is capable of, but for a tank of that size I'd be inclined to go with a high flow, lower pressure pump.
Out of interest, my 80 ltrs/min pump has 1½" connections and my Mono at only 12.5 ltrs/min has ¾" connections.
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My current processor, albeit is not plastic produces excellent biodiesel passing 10/90 tests with ease and the reaction takes place at 55deg. It also dries my biodiesel well and I demeth by water washing.
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This might shed some light on pipework sizing:
(http://www.pump-magazine.com/pump_magazine/pump_articles/article_15/article_15_files/image001.jpg)
In biodiesel manufacture, not only are we using a pump for moving fluid around, we're also using it for mixing. This is a bit of an odd requirement for a pump - they're normally designed to achieve a required pressure for pushing fluid down a pipe. In our application, pressure needs to be around ~0.2 bar to push it back to the reaction vessel - but we need a massive flow rate to get the mixing we want. This is well outside the bounds of the optimum operating point of most pumps (one of the reasons why eductors work so well in our application), but there are a few things we can do to help matters.
In the graph above, you can see how suction pressure varies with pump flow rate. To get the maximum flow, we need to minimise the pressure drop down the suction pipe. Generally speaking, this is more critical than the pressure drop in the discharge pipe because the pumps we're using have a design point with more pressure than we're putting on them.
You can also spin the pump faster than the design speed. Great if you've got a VFD driving your pump, more difficult if not. You really do need to ensure that you've got a good pressure on the inlet though - too fast and you run the risk of cavitating. I found my pump starts to cavitate at about 85Hz - it also pulls far too much current at this speed, but 60 works very well. It's hard to do a like for like comparison of flow rates without flow meters, but the pressure gauge on the discharge sits about 0.05 bar higher than at 50 Hz.
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im not sure here as I don't do bio, im a veg runner, but isn't 55c not hot enough for reaction/dewater/demeth ? that's all a hdpe tank can handle...
...which is why I said what I said in post 4 of this thread.
yes I see that just wanted to mention again, not just for here but others reading the importance of plastic tanks and the use of, there was a post somewhere about an emertion heater bending when hot and touching the side of tank and burning through...
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im not sure here as I don't do bio, im a veg runner, but isn't 55c not hot enough for reaction/dewater/demeth ? that's all a hdpe tank can handle...
...which is why I said what I said in post 4 of this thread.
yes I see that just wanted to mention again, not just for here but others reading the importance of plastic tanks and the use of, there was a post somewhere about an emertion heater bending when hot and touching the side of tank and burning through...
I agree with RM, it can't be stated too many times. This is one of the reasons ...
(http://www.biopowered.co.uk/w/images/thumb/9/98/MeltedHDPEprocessor.jpg/250px-MeltedHDPEprocessor.jpg)
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This might shed some light on pipework sizing:
(http://www.pump-magazine.com/pump_magazine/pump_articles/article_15/article_15_files/image001.jpg)
In biodiesel manufacture, not only are we using a pump for moving fluid around, we're also using it for mixing. This is a bit of an odd requirement for a pump - they're normally designed to achieve a required pressure for pushing fluid down a pipe. In our application, pressure needs to be around ~0.2 bar to push it back to the reaction vessel - but we need a massive flow rate to get the mixing we want. This is well outside the bounds of the optimum operating point of most pumps (one of the reasons why eductors work so well in our application), but there are a few things we can do to help matters.
In the graph above, you can see how suction pressure varies with pump flow rate. To get the maximum flow, we need to minimise the pressure drop down the suction pipe. Generally speaking, this is more critical than the pressure drop in the discharge pipe because the pumps we're using have a design point with more pressure than we're putting on them.
You can also spin the pump faster than the design speed. Great if you've got a VFD driving your pump, more difficult if not. You really do need to ensure that you've got a good pressure on the inlet though - too fast and you run the risk of cavitating. I found my pump starts to cavitate at about 85Hz - it also pulls far too much current at this speed, but 60 works very well. It's hard to do a like for like comparison of flow rates without flow meters, but the pressure gauge on the discharge sits about 0.05 bar higher than at 50 Hz.
Any chance of a wiki page on that, James? It would sit well with the Pump buyers guide page.
We've had people with large processors that didn't work efficiently only to find, after some detective work, they were using 15mm pipework.
I'm happy to redraw and alter any diagrams or graphs you may need.
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im not sure here as I don't do bio, im a veg runner, but isn't 55c not hot enough for reaction/dewater/demeth ? that's all a hdpe tank can handle...
...which is why I said what I said in post 4 of this thread.
I appreciate the risk and the processor will be supervised at all times.
yes I see that just wanted to mention again, not just for here but others reading the importance of plastic tanks and the use of, there was a post somewhere about an emertion heater bending when hot and touching the side of tank and burning through...
I agree with RM, it can't be stated too many times. This is one of the reasons ...
(http://www.biopowered.co.uk/w/images/thumb/9/98/MeltedHDPEprocessor.jpg/250px-MeltedHDPEprocessor.jpg)
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That picture is horrible.
Always a metal tank for me.
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Any chance of a wiki page on that, James? It would sit well with the Pump buyers guide page.
We've had people with large processors that didn't work efficiently only to find, after some detective work, they were using 15mm pipework.
I'm happy to redraw and alter any diagrams or graphs you may need.
Could do...if I get time.
Seeing as I wasn't busy enough I thought I'd take on two full time courses at the same time. I foresee a bit of a meltdown soon. Much like that reaction vessel actually!
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I'm not ashamed to say that I prefer Plastic to metal anyday. Over the years I have been careful with them and have never had a problem.
I don't de-meth as using a total of 13% methanol, I don't see the point.
With the TAM 120 I have checked the flow when filling the processor with oil at 11degs C and it is down to 34lpm. However the delivery pressure is massive.
After the methoxide is added, because methanol is not miscible with vegetable oil the resultant mix is opaque in nature. This effect will clear when the mix is about 75% converted. This to me is a good indication of the pump/processor efficiency.
In the past when I have used a weak pump this opaque nature of the mix can last 20 to 30 mins, resulting in KOH amounts of up to around 12gms/litre even on good oil.
With my present set-up even at ambient the opaque mix will clear within 5 mins and doing a 10/90 at this point in the process shows around the 85% conversion level. This is really the result of using a tam 120 with a 1/2" eductor.
The disadvantage of bio boy's very large processor as well as the pump he would use is that to heat the oil in a reasonable time he would need 2 if not 3x 3KW immersions.
It all can get too big to be practical very easily when doing things at home.
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this pump may sought him out ;D
http://www.ebay.co.uk/itm/111655226718?rmvSB=true
(http://i.ebayimg.com/00/s/MTYwMFgxMjAw/z/FLYAAOSwBahU2Sec/$_57.JPG)
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I'm not ashamed to say that I prefer Plastic to metal anyday. Over the years I have been careful with them and have never had a problem.
I don't de-meth as using a total of 13% methanol, I don't see the point.
With the TAM 120 I have checked the flow when filling the processor with oil at 11degs C and it is down to 34lpm. However the delivery pressure is massive.
After the methoxide is added, because methanol is not miscible with vegetable oil the resultant mix is opaque in nature. This effect will clear when the mix is about 75% converted. This to me is a good indication of the pump/processor efficiency.
In the past when I have used a weak pump this opaque nature of the mix can last 20 to 30 mins, resulting in KOH amounts of up to around 12gms/litre even on good oil.
With my present set-up even at ambient the opaque mix will clear within 5 mins and doing a 10/90 at this point in the process shows around the 85% conversion level. This is really the result of using a tam 120 with a 1/2" eductor.
The disadvantage of bio boy's very large processor as well as the pump he would use is that to heat the oil in a reasonable time he would need 2 if not 3x 3KW immersions.
It all can get too big to be practical very easily when doing things at home.
I have done my research and plan to run 2 36" 3KW Immersion heaters, 1.5" pipework with the flow taken car of by this pump:
http://www.oilybits.com/pumps-for-liquids-/pedrollo-pro-nga-open-impeller-316-stainless-steel-centrifugal-pump.html
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What you really need is a bio fired boiler. 24kW heats up oil pretty damned quick!
Funnily enough...I have one that needs a new home. ;)