Hi,

After successful results with small batches, I've built a larger processor from a 100L water heater.

I used it to process 40L of WVO with methanol and NaOH, with no particular problem except the byproduct went solid and clogged my processor I will use KOH next time.

I've then tried to bulk wash a 10L sample in a jug (I dont have an air bubbler yet). It worked quite great, with a quick separation of the biodiesel and water layers.

However, I'm now running into a big problem, the washed biodiesel won't dry. I've let it settle for 10 days in an open container, it's still cloudy.

I've tried heating a 1L sample to about 70°C, it went clear for about 6 hours with a small quantity of white liquid settling at the bottom, but then it begun to get cloudy again.

I've had much better results with a very small sample (about 10cL) that I heated a lot, it went extremely clear like good quality fuel and did not get cloudy after 3 days.

But heating the 40L as much as I heated the 10cL sample means wasting a lot of electricity. Any suggestion? How long does your biodiesel takes to dry when you don't heat it ?

Thanks.

By the way, the oil titration result was very low, I used 1mL of the NaOH titration solution (tried 3 times, same result).
I got the WVO from a school restaurant, I believe they have strict rules about how they should use their oil.

lk: do you have a means to circulate the bd? It won't dry by just sitting - the water-laden part sinks to the bottom, away from the air. It can be "bubble-dried". Is the container wide-open to the air? I've proven to myself that a 1-gallon glass jug won't dry bd without a bubbler. Even an open top 55-gallon drum won't dry a load of wet bd without circulation.

Well, I've read somewhere that settling washed biodiesel in an open container should dry it in a week or so. Apparently, this was wrong.

To circulate I could use my mixing pump, but 800W electrical consumption and 3600L/h are a bit violent and energy-consuming (it's otherwise very good at mixing methoxide within a dozen minutes ). And I dont want to leave it unattended - what a mess it would be if the output pipe leaks and squirts biodiesel everywhere.
So I think the best thing to do then is to get myself an aquarium air bubbler, which I need for easy washing anyway.

glycerol solidifying in the processor is a nightmare ive encountered twice and now take steps to avoid. Make sure you drain it before it gets cold. there will always be some residual glycerol dropping out for 12 hours or so afterwards, but that hasnt bothered me so far.. the heat in the biodiesel seems to stop it from going solid. If all the glycerol is left the stuff sitting in the pipes and at the bottom of the tank will go cold and harden into something like rubber.

Hi, I use two air bubblers to dry my 80 litre batchs of Bio, usually takes two days then its crystal clear.

This message has been edited. Last edited by: Shaun,

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You guys are well behind. I use a clear water pump and spray dry my Biodiesel and I can usually get it dried in about 8-10 hours or less depending on Humidity. I am looking into using a dehumidifier on high humidity days. Also, I have bubbled it all day and this helps cut time off the spraying. I am going to try to attach an image of my sprayer.

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Here is another image. Wish there was a way to attach multiple images.

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Nevertheless, I gave my batch one more wash and then used an air bubbler I bought for 10 euros on Ebay - after a dozen hours, it went crystal clear

You're certainly right about spraying, but it requires more room, equipment and energy.

Thanks !

quote:

How long does your biodiesel takes to dry when you don't heat it ?

I circulate with a 1 gpm 12v pump onto the side of the drum, with a fan pointed at it. If the fuel is well washed, it will dry in a few hours this way, depending on humidity.

More complete washing = easier drying.