Biopowered - vegetable oil and biodiesel forum
General => Chatter => Topic started by: Tony on November 11, 2011, 09:05:13 PM
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Welcome to the forum 8)
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Well thank you!
I'm just about to start construction on my processor, and it looks like you guys have a pretty good handle on how to do it.
Thanks in advance for all the help.
The nickname "joggerfogger" is what my friends used to call my old 6.5l diesel powered K5 Blazer. It would frequently belch out a thick blanket of soot on unsuspecting joggers going up the hill to my house.
-Kevin
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Ah, the kind that leaves it's own stealth fog trail up hills, I had a diesel that did that ;D
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Welcome,from the USA? yes :)
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Yes, welcome.
It will be great great to have a US perspective and input.
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Oh, by the way, how's the venturi coming along? Have you tried it in anger yet?
It would make an excellent addition to the wiki.
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Oh, by the way, how's the venturi coming along? Have you tried it in anger yet?
It would make an excellent addition to the wiki.
I will gladly post it up once it's proven to work. I just finally received my pump yesterday, and I have recently made several changes to my design. I had a great phone conversation with a guy that gave me some good ideas about my design. He also said that based on the goals I have for my processor, I really should be focusing my studies on the UK design philosophy. (that's why I'm here!)
This is my latest design, but I already know that I need to make the vapor return higher than the top input after the venturi to prevent any back-flow of oil out of the venturi. And if my venturi works as planned, I'm going to draw the methoxide with it. I just want to be able to do it both ways depending on how it works out.
(https://lh4.googleusercontent.com/-wd_B7oMR9RA/TryrK5rYgZI/AAAAAAAAYtE/Twi7nGtRC6g/s529/GLADYS%252520v2.jpg)
I'm trying to work out as many kinks in my head before they surface in practice, but at some point I have to just dive in. After visiting 4 hardware stores and going over my plans again and again, I decided that I'd rather fabricate some simple parts instead of buying 4-5 parts and screwing them together. I can see the benefit of working with copper (as it seems most of you do) but I decided in the beginning that it was going to be all steel pipe, and steel is my preferred medium.
Tonight I made 3 of these 1x3/4x1 Tees, and I now need to modify my water heater to a 1" drain on the bottom before I start building. I'm going to guess that it will be at least another 2 weeks before I try my first batch.
(https://lh5.googleusercontent.com/--_4cf1ZuK_M/TsSxB735X_I/AAAAAAAAY5k/n76RzLsjBpE/s640/1x.75x1.JPG)
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Tidy welding :) Good luck with the build!
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Welcome to the UK philosophy (perhaps that should more correctly be the GL philosophy!). If you need any advise just post on here or the VOD, there's always people willing to help.
With regard to moving the venturi, I would certainly agree with your thinking ... I did the same with my processor when I first built it. It seemed wrong for it to be located lower that the oil level in the processor. The higher position usual means the it has to be positioned horizontally which has, in the past, not been considered the ideal orientation. That said there are many who have fully operational venturies working horizontally, myself included. In fact I've had several designs of venturi all perform well when horizontal. Only one failed to establish suction and that was cured after a little research of various manufacturers websites and some experimentation. The solution was to install a jet splitter, shown at the bottom of the venturi page on the wiki.
Ironically I have a feeling that venturies which are accurately made are more prone to "jetting" through the discharge cone. Most of mine have the throat drilled to size on a lathe and hence are likely to suffer the problem. With your venturi, it may pay you to first try it as a "welded finish" and see how it performs, them drill the throat if necessary.
I've always thought that working with steel pipe must be a right pain in the backside, you have my sympathy, but your solution looks to be an excellent one, nice welding as Tony says.
Good luck with the build, as you say you'll have to bite the bullet at some point. Don't try and attain perfection ... if you are anything like most serious home brewers over here, you'll be modifying it within a couple of months as new ideas and processes come to light!
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My first processors had a horizontal venturi feeding into a spray arm (stoppered and drilled 22mm pipe). This must have given adequate back-pressure.
I've since moved to vertical with a swept 90 afterwards. This seems to cause slurp-slurp-slurp noises. Next one will be horizontal again with a jet-breaker like Julian uses.
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My current one's a four port effort ... on occasions it gives out a low whistle! Can't quite make out the tune though.
Don't install a jet breaker unless you have to. You'll only need it if the flow from the throat doesn't fill the pipe at some point down stream of the ventrui.
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Just enough to get the liquid to stick to the surface of the outlet cone as it exits, right :)
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I made little progress this weekend. But I'm almost done with the reactor. I replaced the wooden stand I made with a metal one (recycled bed frame) that's higher, stronger, and has more room. I'm to a point where I need to know what I'm going to do for a settling tank/wash tank/dry tank. It seems that there's as many ways to handle the fuel after the reactor as there are ways to build the reactor and I'm not sure how to proceed.
I need the purest biodiesel. I have a 2007 Duramax truck, and I've successfully been running commercially purchased B99 since I bought the truck in 2009. I was planning on following the procedure of a guy in a nearby town that has the same truck, but he uses a Fuelmeister that he bought 6 years ago. (it's a basic plastic cone bottomed kit that relies on pre-heating the oil). He has a wash tank that sprinkles warm water over the fuel, then he dries the fuel with a heated barrel and bubbles.
I'd like to use the best process possible for treating the fuel. Not sure what that is. Since I'm following the GL style processor, I'd like to follow suit with my post-reactor process.
-Kevin
Thanks again and in advance for any advice. Here's some pics of my progress:
(https://lh5.googleusercontent.com/-JTOJuYFi0qs/TtPPY58CEKI/AAAAAAAAZQM/i80TireC2Js/s720/IMG_3544.JPG)
(https://lh5.googleusercontent.com/-8KKi0ML54Y8/TtPPVfzYI7I/AAAAAAAAZPw/_8vOdS_7vj8/s912/IMG_3539.JPG)
Here's the core of my condenser. I ended up having to solder on the caps to keep them from leaking. Copper is super expensive here and I had some PVC pipe laying around, so the water jacket is PVC. Hopefully the effect is the same.
(https://lh5.googleusercontent.com/-vYzdlH-yYyA/Ts07fufFBVI/AAAAAAAAY_w/gt-AwHGbAa4/s912/condenser%252520core.JPG)
-Kevin
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Threaded steel - that's proper man's pipework that is - planning on trying the same on my next processor :)
It sure is looking good, with the GL you'll have the flexability to do it a number of ways - just see which process suits you the best.
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Progress is looking good so far.
Only problem you may have with a plastic outer skin on your condenser is the junction with the incoming vapour pipe. The pipe can get quite hot depending on the temperature at which you demeth. These days I rarely go much over 80°C, but some people take the temperature higher. You may well be ok if you can ensure the plastic section is totally filled with no air space.
You're right, there are many opinions on the best way to finish bio. I think it's generally accepted the water washing usually produces the cleanest bio, but many folks get very good results by demething as much as possible, doing a 7% water wash in the processor then pump to a settling tank and bubble over night and settle for as long as possible. You can then pump through a dry wash tower, filter (say 5µ) and into the car.
It's a lot less messing around and more energy efficient than water washing and the way I've made bio for several years, but then my old Disco isn't too fussy on fuel quality.
I agree with Tony, try various ways and see what suits you best.
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Only problem you may have with a plastic outer skin on your condenser is the junction with the incoming vapour pipe. The pipe can get quite hot depending on the temperature at which you demeth. These days I rarely go much over 80°C, but some people take the temperature higher. You may well be ok if you can ensure the plastic section is totally filled with no air space.
Hummm. There will be a small airspace over the upper outlet. I'll have to thread an air purge to make sure it doesn't overheat. I looked up the melting temp of PVC and it's 100-260C, but can have a "glass" point of 85C. Bummer. for some reason I assumed it could handle well over boiling temp. Well, if it fails it will be pretty obvious and it won't kill a batch, just leave some water on the floor.
I agree with Tony, try various ways and see what suits you best.
I don't know if it matters, but I believe electricity and water are pretty cheap in my area. 100 cubic feet of water (~750 gallons = ~3,000L) is $1.79 and is of better quality than most bottled water. I don't know how you measure your water, but that's about 40 pence for 1,000 liters? Is that cheap comparatively? Power is around $.09/kWh. By the math I've done, I came to the conclusion: even at 5x the power cost, it's still a fraction of the cost of pump diesel.
But at the same time, I want a design with streamlined, simple, and effective use of time/money. I'm sure that most of you that are doing this already would do it differently if you had to start over again. That's the plan that I'm looking for. I know there will be improvements, but there has to be a method that's better than the rest. No? or is that too touchy of a subject?
So I have another question: Do you save one barrel for the glycerol, then when you have a whole batch of it run it through just to demeth? Or is the glycerin that comes out of the GL about as pure as it's going to get?
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The problem is there are several variations on a theme. There's no right way of doing things, it really boils down to personal preference and what works for you with your feedstock.
I can tell you the way I prefer to do it, but someone else will inevitably say their way is better. You'll also find you start taking short cuts after you've been at it a while ... then you'll have a bad batch and go back to basics to get it right. Next thing you know you're slipping back into cutting corners again!
My way (without too many short cuts or bad habits) is ...
Filter WVO through landscaping fabric filter socks (http://www.biopowered.co.uk/wiki/Tips_and_wrinkles_1#Homemade_sock_filters) and settle for as long as possible. I believe food particles can retain moisture, so I aim for the oil to be as clean as possible.
Perform HPT and dry oil using condenser if required.
Titrate oil and mix methoxide at something less than the recommended ratio usually about 4.0 - 4.5g per litre (NaOH).
Bring oil to 67°C ish and add 80% of Methoxide. I turn the heater off while adding the Methoxide but run the rest of the reaction with the heater on and the PID set to 63-65°C.
React for about an hour, turn heater off and settle Glycerol for about an hour.
Drain Glycerol, pumps and heater on and add the balance of the Methoxide. Do a 3/27 after about half an hour. If it's OK (I never look for a "perfect" pass, clearish with no dropout is acceptable to me) I carry on to demeth, if not continue processing until a satisfactory pass is obtained. You can take a chance at this point as the initial stage of demeth is no different to processing, so you could accept a small amount of drop out and hope that the first part of the demeth finishes the reaction.
Once 3/27 is ok, add back the first stage Glycerol and start demething. I don't demeth at elevated temperatures and no longer bother controlling the still head temperature, I just set the PID to around 80°C and let the system run until the Methanol has slowed to two or three drops per minute.
Heater off, add 7% water and run for about 15 minutes.
Stop the pumps and allow the Glycerol to settle for an hour or two, or until the temperature has dropped to around 60°C.
Drain the glycerol (add any winter additives and mix for 5 minutes or so) and pump out to a settling barrel.
Bubble dry over night and allow to settle for as long as possible, but at least a week.
If the hoses serving it didn't sweat as much as they do, I'd pump through my dry wash tower and into a second settling barrel and again settle for another week or so.
Then it's pumped out through a 5µ filter and into the car.
If you check out the VOD forum, Hyfly currently has a thread running advocating no titration, instead relying on 3/27 tests to progressively add the second stage methoxide in varying concentrations, then do a couple of full water washes in the processor. Several guys have tried this with some success, my efforts sadly resulted in an emulsion that took a week to break, but have, I must admit, resulted in some of the clearest bio that's left my processor. I'll give the idea another couple of tries as it certainly seems to have it's merits, but if I need a batch in a hurry I'll go back to what works for me.
Hope that helps, but as was said previously ... ask the question of someone else and you'll get a different answer!
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The plastic problem may not be an issue because of the water contact.
A while ago I was experimenting with using a 500W immersion element to heat oil, but I was concerned it would melt through my plastic drums if just lobbed into the drum directly.
I tested a PET bottle in the sink with the immersion on, pressing the immersion into the plastic below water level. There was no way it was going to melt.
What are you using to interface the plastic to the copper? Will there be a washer or seal of some kind?
You could use RTV silicon, the kind used for making gap-filling gasket repairs on car engines - though it doesn't stick well to smooth copper (roughing it up may help?)
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The problem is there are several variations on a theme. There's no right way of doing things, it really boils down to personal preference and what works for you with your feedstock...
...Hope that helps, but as was said previously ... ask the question of someone else and you'll get a different answer!
Awesome stuff. Read it 3x. Thank you. I didn't realize that you do the 3/27 test with the glycerin still in the mix.
What are you using to interface the plastic to the copper? Will there be a washer or seal of some kind?
I bought copper pipe to 3/4" NPT threaded adapters for the core, then drilled and tapped the end caps (plugs) of the PVC. I had to quickly glue and screw the whole thing together. I used an O-ring on the inside and pipe tape for the threads. So the copper adapter is basically in direct contact with the PVC end caps. If anywhere, this is where it will fail. I think as long as I have cold water in direct contact in that area, it will not melt. I have some leftover air bleeders from motorcycle forks that I think will work perfect.
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I didn't realize that you do the 3/27 test with the glycerin still in the mix.
You need to let the glycerine in the sample settle before doing the 3/27 test.
I use this method to speed up the settling ... http://www.biopowered.co.uk/wiki/Tips_and_wrinkles_1#Human_centrifuge
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You need to let the glycerine in the sample settle before doing the 3/27 test.
I use this method to speed up the settling ... http://www.biopowered.co.uk/wiki/Tips_and_wrinkles_1#Human_centrifuge
Ah. Got it. It's all coming together now. I've read both pages of those tips, but didn't catch the accelerated glycerin settling part of that post.
If my first batch goes through without a hitch and passes all tests for purity, I think it will be a miracle.
So are there basically 5 taints that we try to avoid with the final fuel?
1. Catalyst
2. Methanol
3. Water
4. Glycerin
5. Unconverted WVO
I want to make sure I have a method and a test for each of these taints in my process.
Thanks for all your help! I hope to have my first batch going by Christmas.
-Kevin
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Catalyst and glycerine should gravity settle out.
Methanol, you should be able to remove the majority suing the condenser (even so, I air bubble my bio while it is still hot to make sure any trace Methanol is driven off - sometimes this does show up as a drop in liquid level in the drum the next day, so that must be the Methanol).
Unconverted WVO will show in the 3/27 test (will your big block engine care about a little unconverted oil? Probably not!)
Water, again removed by air bubbling - not so easy to test for though.
I don't use water in my process at all, but rely on gravity and hardwood drywash.
Certainly I can't argue that water washing the best guaranteed way to clean the fuel, as it removes all the contaminants you list (except water, of course!)
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Unconverted WVO will show in the 3/27 test (will your big block engine care about a little unconverted oil? Probably not!)
I don't use water in my process at all, but rely on gravity and hardwood drywash.
I know it's an American GMC 6.6L lump, but I think it's pretty sophisticated. The motor is actually made by Isuzu, and has a massive amount of computer controls. The injection pressure goes up to 26,000 psi and uses 3-4 pulses of fuel per cycle. I don't know much about other smaller displacement diesels because other than VW, we don't get all the killer diesel options that you guys get. I don't know, will my truck care about some unconverted oil? sweet if it doesn't.
Turns out, the only water involved in my process is the water that I take out at the beginning. :) Thanks to the advice from all of you.
Cheers!
-Kevin
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If it's electronically controlled injection with high pressure rail, then it's probably a good idea to ensure complete conversion, as you have done with your first batch - well done with that.