hi im new to the site and was wondering if there is anyone that has pictures or helpful instructions on making my own dry wash processor. it would be helpful as to what would be a good process to clean the bio diesel because ive been water washing my BD for about a year and a half and that process takes to long. every time i mist wash it emulsifys.
so my question is does anybody have a step by step instruction manual to making a dry wash processor?
[quote]does anybody have a step by step instruction manual to making a dry wash processor?/quote]
I don't remember seeing any vendor on the forum with step by step instructions; however, there have been many threads on the topic and many photographs of tower construction in progress. You just need to do a little research in this section of the forum.
First, you need to know what kind of dry washing/filtering medium you plan to use. Dry washing has progressed from magnesol to resin and now hardwood shavings. I currently am setup to run my settled BD through a PVC column of shavings and then through my resin columns. If I didn't already own the resin, I would simply use the wood shavings.
A lot of people on the forum will tell you that you can't use PVC for the column. That is not my experience. I have been using PVC for the last 18 months without a hitch. The problems that I have seen with PVC appears to have been caused by the expansion of the resin within the columns. Some have said that it is due to a chemical reaction of the PVC, resin & biodiesel which causes fissures. Again I haven't seen that happen. I use Thermax macroporous type resin which doesn't expand nearly as much as the gel type resins. Again I could be wrong about the PVC, but I am reporting my actual experience and I don't sell PVC or Steel columns or (as far as that goes) anything on this forum.
Many experiments have been conducted with wood shavings. The kind you want to use are hardwood shavings from a cabinet shop, millwork manufacturer, staircase company., et.al. These shavings will be produced from kiln dried furniture grade hardwood lumber using a jointer, planer, router, shaper or moulder.
One of the forum members, Jehu, says that sawdust is better than the shavings. One problem with sawdust is that it is hard to identify what type of wood or board it came from. Typically sawdust in a cabinet shop will come from many sources e.g. plywood, medium density fiberboard, melamine coated board, chipboard, et.al. You don't want any dust from those boards due to the chemicals and glues used in their production. You also don't want dust from softwoods as they contain compounds which could add something to the biodiesel.
If you go the wood shavings route there are some good discussions in this section of the frorum from last year that you might want to look up. The design of a wood shavings tower is simple for the homebrewer. You can take a 55 gallon drum, cutout the bottom, plug the bung hole, attach a 3/4" nipple to the vent hole, attach a valve to the nipple, flip the drum back over and support on a stand or table, fill about 1/3 to 1/2 full of wood shavings, pump biodiesel slowly into the drum, allow the biodiesel to sit for a while in the shavings and trickle drain the biodiesel out into a container. You might want to put some screen material over the inside of the vent hole to keep the shavings inside the drum. You continue using the same shavings until you determine that they are not effective at removing soap anymore. You take the drained waste shavings and put them in paper bags and burn in your wood stove. You could also get to know your local hardware guy and have him help you configure a PVC tower, if you don't have a good plan in mind.
My sawdust is all mahogany. Any hardwood seems to be fine - I even got some amazonian purpleheart wood once which worked fine. You people across the pond swear by red oak, but we dont have that here. I used english (or scottish?) oak shavings from a whisky cooper which worked well until they started selling it to fish smokers. But sawdust was better - did a complete job with no lag time whereas shavings had to pass thru slowly.
Heres my set up, which costs very little - no need for resin towers, which I have but no longer use:
You need three tanks:
1 200L garden water butt with tap, on a stand, 3/4 filled with sawdust
2 200L long low rectangular domestic loft cold water tank
3 storage tank for finished biodiesel - I use another 200L garden water butt
1 leave the raw biodiesel in the processor overnight to make sure glycerol has dropped out
2 pump/decant the raw biodiesel into the sawdust drum, and wait until the bubbling stops
3 turn on the tap and allow to drain by gravity into the low tank
4 pump from low tank into storage tank via RO filter
The butt containing the resin needs some kind of filter at the bottom to catch the sawdust. At first some very fine dust comes thru in the biodiesel, but the RO filter should catch this.
The sawdust will last for months before changing.
New sawdust contains resins which are extracted by the first batch biodiesel. This resin is soluble in biodiesel and burns very well. I've no idea if the resin burns completely in an engine or varnishes injectors and whatnot but Ive had no problem with it. Otherwise the resin precipitates out of the biodiesel with a water wash, and only needs to be done on the first batch - a very small inconvenience.
Demething doesnt affect the performance of the sawdust - I dont demeth.
I get my sawdust for nothing - actually I give the guy a crate of beer and I can fill a trailer with binliners of sawdust which lasts me a year. It gives biodiesel which is very bright and clean.
And one last thing - the spent sawdust is fantastic for burning; I use it in a sawdust burner to heat my 200L stainless steel reactor - free filter medium, free heating.
PS - no more jokes about 'butts' please - over here a butt is a barrel, not a fat arse
Are you removing the methanol, or going directly to the sawdust following glycerin drop out?
Thanks, I guess I missed that. Very interesting.
After a while theres a smell of methanol from the sawdust, which shows its being absorbed, although I think some is still retained in the biodiesel. As for the fumes, a lid takes care of that.
I have been reading about the dry wash method with wood chips and I have just a couple of questions.
Lets start with a batch of 3/27 passed unwashed raw biodiesel that has settled overnite and the glycerin has been drained off.
What is my next step?
Do I need to prewash before settling or can I just filter the straight settled bio through the wood chips? If you prewash how would you remove the water?
Using a 55 gallon drum with oak chips, what would be the rate at which I would filter? Would it be beneficial to circulate it for a period of time through the chips? Or would gravity feed be fine?
I make 2 batches of 30-35 gal of raw bio in each run.
The wood chip dry washing method seems almost too good to be true.It just seems that there should be something else>
Please forgive my ignorance.
Regards to all!
You first need to make sure that all the methanol is removed from the BD. This enables the soap to drop out of solution. I prefer to allow the BD to settle for a couple of weeks prior to running through the wood shavings. Most of the soap will have fallen to the bottom of my settling drum within that time frame. This increases the useful life of the shavings.
Some are having good success at removing the soap after settling overnight. The problem for me with that is you have a larger waste stream to deal with. The wood shavings are great as a fire starter or to just burn in a stove. I just prefer to conserve them.
Water washing removes methanol as well as soap. If you are recovering your methanol, I don't see how water washing would be better than dry washing.
I like to circulate my BD through the wood shavings for some time prior to gravity feeding through my column. The benefit of that is if there is methanol still present, it will gas off while circulating.
Bear in mind that this method of filtering or drywashing BD is relatively new. We just started experimenting with this less than 2 years ago. Nobody has reported any problems with their vehicles yet.
Welcome to the home of the unwashed.
I cant agree with you there Euro. Why would you want the soap to drop out of solution? I dont demeth and have no problems. The sawdust takes care of the soap whether youve demethed or not. On the other hand people who do demeth report that the resultant soap drop out is clogging their filters.
So does drywashing with woodchips/sawdust remove methanol?
Well from what I have learned on this forum and I am not a scientist or chemist, if you remove the methanol, the soap will fall out of solution and to the bottom of your settling drum. At least that is what Graham Laiming's GL1 process is based upon.
The benefit is you don't filter as much soap through the shavings or filters.
Nothing wrong with disagreements, but have you actually had your fuel independently tested to see that you are getting the results you are claiming? Not removing the methanol completely could leave the soap in suspension and not allow removal. I am not willing to take that risk without understanding the science behind it.
There was one guy on here awhile back that claimed that you could leave the glycerin in the fuel and run it. There was an interesting thread about his process on the forum at one time. I think he used ethanol for the reaction. The trick was to keep the glycerine in suspension. The thread died and he has never been back to report his results. I bet they weren't too good.
I am not claiming that your method doesn't give you good results, I would just like to know why it works.
That could be the answer to why it works for Jehu. I just don't see how it is possible to remove the soap with sawdust without removing the methanol. Now an ion exchange resin will do it to a certain extent, but it won't hold up too long without removing the methanol and soap first.
Methanol doesnt inhibit sawdust from absorbing soap - its wood alcohol after all, and the sawdust removes most of that too. Demething is an unnecessary step unless the purpose is to reclaim the methanol. I dont remove the methanol because I dont want soap dropping out in my filters and plumbing like I used to get. I dont bother getting my biodiesel soap tested; I get no soap or glycerol fall-out settling on the bottom of my storage drum like I used to get with resin and water washing. Thats good enough for me.
I'm not saying people should or shouldnt demeth, all I'm saying is that sawdust works just as well if you demeth or not, without the problems of soap dropping out before it reaches it; maybe if the price of methanol goes up a bit I'll demeth too, but right now its not worth the trouble for me.
Has anyone had their fuel tested with this process?
Jehu, So you just run the settled bio that has had the glycerin drained off through the chips and that was it? How big was your chip filter and at what rate do you filter? Very interesting.
...And regarding glycerin in bio...Well it will weld your injectors solid. Not recommended. Not speaking from experience but from a VERY knowledgeable commercial biodiesel maker.
Yes I just pump or decant my raw biodiesel into the sawdust drum. I've a 200L plastic garden barrel holding about 100L sawdust. My batches are between 100 - 150L and they filter by gravity. I dont demeth. One thing I do is while the residual glycerol is settling out overnight I sprinkle 5% hot water into the biodiesel. Its not a wash and its not mixed in - its simply to prevent the glycerol fall out from going solid as it cools.
When I used resin it was a step up from water washing but the resin didnt last very long - in fact a couple of high titrating batches and I was getting soap and glycerol starting to appear in the bottom of my storage drum. I dont get that with sawdust, and it lasts much longer. Since using this method I've never had any problems with the cleanliness of the fuel.
I have been thinking on ways to demeth. What do you guys think of pumping the unwashed bio through a misting head over the 55gal drum of wood chips? Maybe heat it also?
What do you all think?
There's no need to have any other method in conjunction with woodchips/sawdust, its a complete and reliable method - incorporating other methods is a waste of time, effort and expense.
Oil Can Harry's Masters Formula.
It seemed to work for him for some time. I think he stoppoed posting for other reasons than bad results. People get offended by other people for various reasons. No trying it myself though...
mathematical elegance -- desired result achieved with minimal complication
As you have probably read everyone has their own idea on what is best.
I am going to throw mine in to the pot as well.
I recover some of the methanol from the bio via distillation, then pump the bio into an open top drum and bubble air through it for 2 days.
Then I let it settle for a week. Then I pump it through a wood shaving filter to get the last of the soap out.
The filter consists of 1.5m(5') of 100mm(4") pvc pipe. The inlet is from the bottom and out the top.
Experiment a bit and do shake tests to see what works and what doesn't.