Water washing WVO to remove Lye and other crap

[Clay]

Well i think this is my next step. Thinking about changing out my prefilter barrel and putting an 80 gallon conical bottom tank in its place. This will allow me to pour my oil into the 80 gal. tank - up to 50 gal of oil, and wash it with 30 gal. water. Then allow water to settle and drain it off after maybe 2-3 days of sitting. Not sure how well this will work in winter but i may have to settle it for longer than 3 days when its cold...which is okay as i use about 25 gal. per week so if i can process 50 gal. every 2 weeks i will keep up with my consumption rate.
Anyone else here washing oil?
Its no secret washing is very effective in cleaning oil. I was discussing this in detail last night with a buddy who makes Bio-D and he has played with washing oil and his findings are a lower titration level on the washed oil which when making Bio-D, is a huge help. Oils that titrated at 8-9 (really nasty with lots off FFA) then titrated at 4-5 once washed.
Lye will go to the water as well so i won't have to wonder if i have tainted oil anymore.
Basically the process would work like this:
Pour incomming oil into 80 gal. tank. Turn on a heat source to begine heating and hook up a water hose to a mist tube in the top. I figure a float style shutoff valve would be a good idea so an overflow would not happen and let it go...monitor it untill its full of water and shut off heat and water.
Leave it to set maybe 24 hours - maybe longer - drain of the "snot" with a water hose off into the yard somewhere. Pump the washed oil from a point in the drum higher than the very bottom of the cone into the HWH to heat and settle overnight one more time. Then filter and use.
I will experiment with a 5 gal carboy of oil and mist it at different temps and monitor it to see how long settling will take. with a glass carboy i will be able to see very well when the oil and water have completely seperated.

Discuss...

[FastCote]

I bought the inductor tank below (55 gallon) from United States Plastic Corp:

http://www.usplastic.com/catalog/product.asp?catalog_name=usplastic&category_name=20726&product_id=33150

This one was threaded for 2" pipe threads.

for the mister, I bought fogg-it nozzles by Dramm - based on suggestions from the Bio-D guys at infopop:

http://www.utahbiodieselsupply.com/washingsupplies.php#foggit

I had a not-so-terrific first attempt at mist washing. I ended up with a great big emulsion that took tons of heat to break. I haven't been brave enough to try again.

I may give it another go when the weather gets warm but not until then.

[Clay]

Ben, when you washed your oil, was the oil hot or cold, and did you have a "gental" mist or a more agressive stream?
How long did you let it set and settle before you pumped it and created the milkshake? I assume it emulsified when you turned on a pump and it stired up?

[FastCote]

Clay,

It was mid/late summer and the oil was warm, but not HOT (maybe 100 degrees). The plastic inductor tanks have a max working temp of around 140, so that may be an issue if we need the oil to be REAL HOT. The water was cold, straight from the hose. Those FOGG-IT nozzles make a nice gentle mist.

Yes, the pump action did make a milkshake. I tried to drain the water off first, but do a poor job of it. I think that the blue Harbor Freight pump pumps so fast that it pulls the oil down the center through the layer of water in the bottom. I may be necessary to disconnect the pump to drain off the water first - PAIN.

Not sure if the oil and water both need to be hot and, if so, how hot. I welcome anyone who has had luck with this to chime in.

[Clay]

Ben, you mean you didn't drain the water off but you pumped it off instead?? A quick connect fitting to the pump would make it really easy to disconnect and drain, then when you see oil comming out of the drain, stop and pump the rest into your next filtering drum. That was your mistake i think. you must drain the water off first and then i would have a PVC pipe down through the top that would extend just a little ways into the cone portion and lift the oil from the top to assure i got no water if in fact i did not get it all drained off.
That way there is alway a few gallons of the oil in the bottom
140 is plenty hot for this...i think if it were even 120 that would be fine.
Why don't you try it again and report your findings so i don't have to

[FastCote]

...Why don't you try it again and report your findings so i don't have to

Ha!

I will happily make another milkshake if you take the first chug of it


Seriously, I will probably give it another try. It's just too farging cold right now.

[Marv]

^ is watching (or reading) and learning...

[skyskijason]

Clay, you've been reading my mind - hehehe. I'm thinking of heating the oil as you describe, then spraying HOT water using nozzles like fastcote posted. I already set up a 30gal HWH to use for water.

The 'test' I did a couple weeks ago I was using cold azz hose water and fine-mist sprinkler heads. That worked AWESOME really, considering the off-the-chart extent of nasty that oil was. The oil was clear on top immeadiately after misting 15 gals or so. It was still creamy-looking after heating! but clear after washing! The water was tan and I pumped about 10 gals off before hitting oily crap. It STUNK to hell like boil-out too! I plan to pump the oily crap - I think this is the 'snot' I've read about - into a drum and heat and settle it. If there's not much, I will donate it to the renderer.

OK, no drawings yet, but here's some thoughts.

One thing is for sure, we want the oil plenty warm - the whole time we are washing. I'm thinking about using band heater(s) or 2 WH elements. This way, when heating the oil initially, we can put heat at bottom of container - then move it up several inches when washing. We don't want to 'boil' water below the oil...

Its gotta be an unsupervised operation so here's some parts: Use toilet fill valves to control the water flow (in my case, the supply to HWH). Place the valve on side of container (I'm using a drum) and let float dip down into drum - shutting off when desired fill level is reached. You could do 2 of these in series, using the 2nd on a discharge-water drum - also shutting off when full. (The one on washing drum is in case discharge line gets plugged.)

I want to cut the bottom off of some closed-top drums I have and use them upside down for this. Using the 3/4" bung hole, I'll route a pipe up the side of drum to about 6" below top (external standpipe)- then turn 90 deg's and install a valve. From here, the pipe will allow the washwater to fall into the washwater drum - maybe another 55 gal cut a little shorter?? (I also want to be able to easily drain the bottom of both drums directly into buckets/cubies.)

Sooo, fill washing drum to 6" or so below the line where 'standpipe' turns 90 deg with oil and heat to 140-150*. Then begin 'misting' hot water over the oil. When the level reaches the 90 deg in pipe, the (hopefully) water will begin to be pushed up standpipe and into washwater drum.

The trick will be figuring out how long it takes the seperated water to accumulate at bottom of tank. Then, that determines the level of the oil. If the water falls right thru, then more oil. If it takes a 'minute', we'll need a bigger gap from top of oil to standpipe discharge - meaning more water misted before discharge begins.

If ya make an emulsion in either drum - just heat and settle the drum(s) and start over. If it works like we want, drain the wash water into the yard and 'dewater' the oil like ya always did! but use fewer filters and likely find LESS water. :chuckles:

How does that sound?? Thinking makes my head hurt... Thats why I don't do it often! (As y'all have probly figured out by now)

[Clay]

Jason,
I like the idea of heating the water but that is one more PITA of the process. Might definately be benificial but my test is going to begin with cold oil and cold water. That would be the ideal process IF it will work. IF not, i will try heating only the oil and using cold water. Then i will test using warm oil and warm water.
Not sure i like the idea of the second barrel to catch the water though. If i am understanding this right, you would always have water in that pipe even after you have turned off the water? I think it would be simple enough to just mist untill barrel is full, shut it off and let it settle a few days then come out and drain water off using a clear hose so you can see when the oil begines to flow.
Another idea we are going to work on is a homeade cone bottom barrel. Not actually a cone but let me explain.
Take a plastic drum cut top out and turn it over and sit it on a 5" length of PVC so the pipe is resting right in the center of the drum botton inside and barrel is not touching the ground. using a heat source like a torch, begin heating the barrel bottom evenly all across the entire surface. once the plastic becomes soft from the heat, the battel will start to sag under its own weigh and creat a "sump" in the bottom with a flat 5" surface in the center. When you get 2-3 inches of "sump", let it cool this way and turn it over. Now there is a "low point" in the barrel on bottom with a flat 5" circle in the middle where a 2" valve can be installed for drainage of the water. Build a stand to support the barrel and plumb in a valve and drain hose. i would then plum in a hose into the side of the barrel aprox 4-5 inches up on the side. This will be plumbed to the pump that will suck washed oil into the HWH for final processing.
So fill drum with oil to about 2/3rds full and mist with 20 or so gallons of water till barrel is full and leave to settle. The clear plastic barrel will allow me to see the layers of seperation i hope. Drain off water and pump into the HWH and heat and settle and filter.
Simple i think...

[skyskijason]

I don't think the cold oil/cold water is gonna work. Cold water, yes - but if the oil is cool, the water will not 'fall thru' very fast. This may be ok if you will be settling for extended times, but I want to expedite the process. As for the hot water, well, I have a perfectly good 30 gal WH just sitting around and will run it on 110v ('recovery time' is not an issue at this low volume of water). I know from experience washing bio-d that hot water works better/faster - ESPECIALLY in cold months! We will likely be using the same WH for bio-d wash water as well.

The 2nd drum to catch wash water is so I can 'wash' the oil in a continuous process until the water is clear. Maybe the 20 gals you are considering will be enough water? (how will you know batch to batch?), but then you are limited in how much oil you can wash each batch. I'm hoping to wash 40+ gals/batch and be able to 'set it and forget it' while washing. Also, if I make an emulsion - it does not end up on the ground and I have a chance to recover it easily (just H&S in that container).

The standpipe will have water in it - until you drain the water off the bottom of the oil (same as your plan). How is that an issue? I was more concerned about the slug of oil that will be pushed out before the water, figured I'd have to drain that off before beginning discharge into waswater container....

Ideally, my mist wash drum/container can also be my heat & settle vessel. Simply H&S after draining the water from washing... If all this works like I want, it'll take a few minutes to fire it up, then a couple hours (unattended) to wash, then drain washwater from bottom of wash drum and then reheat oil for H&S right away. If oil is still warm enough (hot water and heating oil while washing will help this!), we may be able to just come back in 12-24hrs and drain water to find DRY oil above it - no 'additional' heat and settle. Many have found mist washing to be quite effective at dewatering VO!!

Thanks for the feedback!

[Clay]

I don't think the cold oil/cold water is gonna work. Cold water, yes - but if the oil is cool, the water will not 'fall thru' very fast. This may be ok if you will be settling for extended times, but I want to expedite the process. As for the hot water, well, I have a perfectly good 30 gal WH just sitting around and will run it on 110v ('recovery time' is not an issue at this low volume of water). I know from experience washing bio-d that hot water works better/faster - ESPECIALLY in cold months! We will likely be using the same WH for bio-d wash water as well.

Oh i am almost certain in my mind that cold VO won't wash well, but my partner wants to see it for himself and I am curious as to what min. temp is optimal for washing.

The 2nd drum to catch wash water is so I can 'wash' the oil in a continuous process until the water is clear. Maybe the 20 gals you are considering will be enough water? (how will you know batch to batch?), but then you are limited in how much oil you can wash each batch.

Not really limited, i will be able to drain water off while the wash process is still going, in fact thats my plan and once i see the water cleaing up, i can choose to stop the wash and let the remaining water settle out then drain it off. There is no way i will leave this operation completely unnattended...just can't make myself do that when i picture the mess i will find if something goes wrong. So i can start the wash, go make a few laps around the yard on the mower and stop in and check it (drink a beer) drain some water, and return to mowing another lap or 3 so partial attendance at a min. This way i am not limited to how much water i can wash with.

The standpipe will have water in it - until you drain the water off the bottom of the oil (same as your plan). How is that an issue? I was more concerned about the slug of oil that will be pushed out before the water, figured I'd have to drain that off before beginning discharge into waswater container....

I guess i am not visualizing this standpipe design properly.

Ideally, my mist wash drum/container can also be my heat & settle vessel. Simply H&S after draining the water from washing... If all this works like I want, it'll take a few minutes to fire it up, then a couple hours (unattended) to wash, then drain washwater from bottom of wash drum and then reheat oil for H&S right away. If oil is still warm enough (hot water and heating oil while washing will help this!), we may be able to just come back in 12-24hrs and drain water to find DRY oil above it - no 'additional' heat and settle. Many have found mist washing to be quite effective at dewatering VO!!

Sounds good, let us know and take some pics!

[skyskijason]

I guess i am not visualizing this standpipe design properly.

The standpipe is what allows continuous washing. It empties the bottom of the tank, but not until the level in the tank reaches the height of the standpipe. So the piping comes out of bottom of tank and runs up beside the tank. The tank will 'overflow' thru the standpipe, but from the bottom... Same way a fitting near the top of the tank would allow product to escape at that level, except this will allow (actually push) the water out of the tank. As soon as I get my scanner set up here I'll scratch out a sketch. Then my (lack of) brilliance should become clear.

The more I think about it, a conical tank sure would be more efficient! Maybe just suspend 2 WH elements at different levels for heating...

THIS combined with second drum (and auto shut-offs/timer) is what will make safely 'unattended' washing possible - eventually.

[FastCote]

The only down side the to cone bottom tank was the cost. I looked all over trying to find mine.

I would worry about Clay's idea of heat-welding a regular poly drum and then heating the oil over and over again. Not sure what would happen over time.

[Clay]

The only down side the to cone bottom tank was the cost. I looked all over trying to find mine.

I would worry about Clay's idea of heat-welding a regular poly drum and then heating the oil over and over again. Not sure what would happen over time.

Not going to heat weld it, rather heat deform it and then when heating the oil i will likely not heat it more than 100* which should be fine.

[greasedltn]

Make sure you have a large standpipe. I've seen the same design on other systems and the crud don't want to co-operate and will stop up the standpipe sometimes. Just my .02. I do like the idea you have and wish you all the luck. Let us know how it turns out.