Biopowered - vegetable oil and biodiesel forum
Biodiesel => Biodiesel equipment => Topic started by: BANDIT2 on January 07, 2022, 01:34:53 PM
-
I've never done it, in fact, I even stopped doing the 5% pre wash years ago, stopped meth recovery as well. I do glyc wash though and also bubble the raw bio overnight with a copper bubbling ring then just settle. This has served me well over the years even though the bio can take an age to clear (Koh) especially in the winter, I'm usually well in front with bio production so it's never been an issue. However, I've been caught out twice in the last 12 months with illness and not being well enough to make it but still using it so the wife can get to work. I've even had to buy Dino on a couple of occasions ( that was a shock at 22mpg!)
Water washing is a way to get better fuel and quicker so that's what I want to do.
I've been looking at misting nozzles and also bubble washing using a pond stone and I think the ceramic stone bubble washing is the easiest with my set up.
Couple of questions though..
I've seen stones with top and side air entery, the top entery ones would be easier to install, they are like Christmas puds in shape but sizes vary, any tips on what size to get?
What tube should I use to run from the stone and out of the top of my 205 drum? Special bio proof stuff?
On the wiki it says to add 10% water to the bio, this would be 18ltrs in my case, can this be just poured in via a bucket or would a watering can with a rose be preferable to avoid an emulsion?
My settling tank, soon to be wash tank has provision for an immersion element so drying shouldn't need to many mods to my drum.
TIA.
-
I'm so sick of this Forum logging me out! I've just typed a really comprehensive reply to Bandits post only to find I've been logged out whilst doing it and lost the bloody lot. I have to log in every 24 hours, bloody stupid!
-
I'm so sick of this Forum logging me out! I've just typed a really comprehensive reply to Bandits post only to find I've been logged out whilst doing it and lost the bloody lot. I have to log in every 24 hours, bloody stupid!
When you log in, do you use the screen attached? and if so do you tick the "always stay logged in" box?
-
I use nylon pipe and a ceramic, cylindrical stone and a control valve.
I chuck in about 10lts of water for the post reaction wash. Never had an emulsion and its pump washed.
Plenty of folk pump washing instead of bubble washing. Not me though. Properly old school. Two days from post reaction wash to filtering the finished bio and putting it into storage.
-
I'm so sick of this Forum logging me out! I've just typed a really comprehensive reply to Bandits post only to find I've been logged out whilst doing it and lost the bloody lot. I have to log in every 24 hours, bloody stupid!
When you log in, do you use the screen attached? and if so do you tick the "always stay logged in" box?
I do indeed Keef, makes no difference.
-
I use nylon pipe and a ceramic, cylindrical stone and a control valve.
I chuck in about 10lts of water for the post reaction wash. Never had an emulsion and its pump washed.
Plenty of folk pump washing instead of bubble washing. Not me though. Properly old school. Two days from post reaction wash to filtering the finished bio and putting it into storage.
Not quite sure what you are saying here, Nigel.
If you are bubble washing, where does the pump come in ?
Dave.
-
I assumed he meant the 5% prewash carried out in the processor before moving the bio across to the wash tank for bubble washing?
-
Another question guys.
Do the ceramic stones clog up with soap etc and, if so, can they be cleaned by, say, 150psi up the inlet? Or would it be advisable to get a couple for spares?
-
Dgs...what bandit said in #6. Post reaction wash or prewash as some like to call it is 10lts venturied in and pumped around for 10-15mins. Brings the soap ppm's down loads before the transfer to the wash tank ;)
-
Chris..the ceramic stones never block up. They sit in the water layer quite happily.
-
Dgs...what bandit said in #6. Post reaction wash or prewash as some like to call it is 10lts venturied in and pumped around for 10-15mins. Brings the soap ppm's down loads before the transfer to the wash tank ;)
It was me who posed that question, not dgs.
Thanks for the response.
-
So it was. Apologies all round me thinks :-[....didn't read the post properly.
Hope my methods and posts have cleared a few things up DavidA
-
Dgs...what bandit said in #6. Post reaction wash or prewash as some like to call it is 10lts venturied in and pumped around for 10-15mins. Brings the soap ppm's down loads before the transfer to the wash tank ;)
Indeed, I always do it(or at least my version) If all goes well soap is about spec level (around 70ppm) after doing this and before water washing.
-
Wow! Down to 70ppm. That is very impressive.
When I conducted tests I went from 13000 to 1300ppm using the prewash/post reaction wash method. Catalyst used will have a direct coraltion to results. The top and bottom is its a no brainer.
-
Wow! Down to 70ppm. That is very impressive.
When I conducted tests I went from 13000 to 1300ppm using the prewash/post reaction wash method. Catalyst used will have a direct coraltion to results. The top and bottom is its a no brainer.
I went through a spell of getting the soap down to <66ppm after the pre-wash by settling and bubbling. The bubbler was 10" off the cone bottom so the wet glyc could still settle. It was as if the vibration of the bubbles were encouraging more glyc to fall.
I don't bother with that any more as the soap cut off level as to emulsion/no emulsion is roughly 500ppm and as using the method leaves the bio so low in soap its not worth the effort to switch the bubbler on and off so I just let it settle.
Over on the Facebook forum it seems some of the bubble and settle guys are having trouble with the present high r/h levels adding moisture to the bio and leaving it cloudy. I've been telling them about the benefits of drying air through silica gel.
-
Just re read your post Dave
..still no idea what r/h.means. But, I too got results below the recommended ppm of soap but only after a few washes with water......never after a prewash. Only ever settled once..
slow, (NaOH)....never again.
-
Nige - r/h - relative humidity
-
It was as if the vibration of the bubbles were encouraging more glyc to fall.
Having seen how bouncing some bio around in a container in the boot seems to encourage a little extra soap to drop, I have long pondered sticking a speaker in a plastic bag, dangling it into the bio and playing some "phat beats" to encourage it to drop faster.
-
Bit of Flat Eric.
That's going back a bit. ;D
-
I have never used any other method than water washing in my BD making process. Now it takes a 7-ish% pre-wash & 4 more 15 litre water washes (v. occasionally 5) to get a clear pass on 140L of BD. I use one machine for the entire process from beginning to end. I always use cold water for all water washing. You can do this ww process at any temperature & I usually do it at ambient.
What I've learned:
I suppose it's obvious but always bear in mind it's the process that creates the problems, so be scrupulous in following the basic rules & you will eliminate many of the problems rather than create them.
I used to try to make a batch of BD too quickly, sometimes in one long day. Now I have broken the process up into several days.
Day 1 - Drying the oil is very important. I get my oil from 2 sources & they decant from their fryers the morning after they used the oil for the last time the night before so it's pretty water free. I crank the machine with 140L of WVO up to about 70 degrees & leave it for 2 hours then drain off what little water there is. I then turn on the pump to get the WVO in the pipes, pump etc into the body of the machine & leave it for another 2 hours, then drain. There's usually no water coming out at this stage.
Then Stage 1 followed by Stage 2
DO NOT over dose with chemicals, if anything be conservative on Stage 1 & accurate in your calculations for Stage 2. Doing this will save on chemicals & save an enormous amount of time & frustration in sorting out overdoses, emulsions etc. Ask me how I know this.
I do the 7% pre-wash & I usually do it immediately after stage 2 without stopping or checking my BD is fully converted. I've done this process so many times I know it's 100% (or as near as dammit) converted. The thing to be careful of here to avoid an emulsion is the speed in which the pre-wash water is introduced. Too quickly & you risk an emulsion so take your time. I introduce the water for the pre-wash slowly through the venturi, the same way & speed I introduce methoxide, & once it's safely in I open all the valves & pump wash with the same ferocity as I use when converting feedstock to BD. It can take 7 or 8 minutes to add 15L of water. I run the pre-wash for 15ish minutes full blast & then shut the thing down for the night.
Day 2 - Water washing day. After sitting overnight following the pre-wash I drain away a lot of potential issues when I drain the pre-wash water. In the next wash I pour the 15 litres in the top of the machine at a gentle rate (not just dumping it as fast as I can) while it runs at about 40% speed, then when it's all in I close the lid & crank it up to max. After that the risk of emulsion seems to be eliminated & I can just dump 15 litres straight out of a bucket into the machine.
I run each ww for about 20-25 mins & then leave it a couple of hours to settle.
After the 3rd ww I test & can usually tell whether I'll be done with 1 or 2 more washes. When I have a pass with a clear separation & clear water in a jar after shaking vigorously & settling I let the converted & now clean BD sit in the processor for a day or 3 to allow the water to drop out, then I dry it by heat.
I've often wondered if just how dirty their BD is is a concern for people who don't water wash. Seeing the stuff that comes out in my water washes I have to say that even though it can be a time consuming PITA I wouldn't make BD any other way.
I do not make BD from about October until the beginning of May, making enough in the warmer months to last me through the colder ones. I NEVER have any glyc, soap, water or anything else in the bottom of the 25L containers I use to store made fuel, even if they've been sitting in my fuel reserve for 6-8 months.
-
Neisel, what a good post. There are a few points that I don't totally agree with but it obviously works for you, good to see a nice long technical post.
So, not being critical at all but just a couple of comments.
You don't mention glyc washing at all, just heating to remove the/some water. Suspended and dissolved water in oil can be very high, much higher than in bio. Glyc washing will reduce the dissolved water to <500ppm.
When you say you add your water for the pre-wash slowly there is no need, really there isn't. It may look as if you have made an emulsion but as long as your mix of glyc and water is roughly 50/50 it won't emulsify. For your batch size of 140 litres you need about 3 litres of glyc and the same of water. (so don't waste/wet your precious glyc that you can use for pre treating)
Pure Glycerine has a sg of 1.4 and our glycerol has a sg of 1.2 so when mixed 50/50 with water it still has a sg of 1.1 As bio has a sg of about 0.9 the wet glyc will always settle (no matter what the mix looks like when the water is just 'slung'in).
-
Bit of Flat Eric.
That's going back a bit. ;D
Haha - can you imagine the neighbours wondering why there are faint, watery tones of Flat Eric on repeat for hours at a time from the garage? :D
-
I've often wondered if just how dirty their BD is is a concern for people who don't water wash. Seeing the stuff that comes out in my water washes I have to say that even though it can be a time consuming PITA I wouldn't make BD any other way.
I'm under no illusions that my "settled only" washed bio is less than perfect and that water washing it would improve the quality.
So mine is "good enough for me", and the odd bit of red stuff in the fuel filters and whatever lines the fuel system doesn't seem to really cause any grief.
I had a Bosch VE on the Delica that got damaged by bad commercial bio from the early days (wrecked the tolerances on the lift side of the pump as far as I can tell) and after I swapped it out and took it apart, from what I remember it only showed minor discolouration of the governor mechanisms and pump innards - and that was after many years of use on unwashed bio. I do remember finding some red jelly goo in the tank though, which blocked the pickup strainer at one point (until that strainer was unceremoniously dumped in the bin).