Fitting a Heating Element

[Hamish Biofuels Forum Newbie Find all posts View Profile Close Hamish]

Hi All, I am going to fit a Heating Element to my bio-diesel proccesor.
I will wire in a switch into my control panel, with all of my other switchs
("Mix","Pump" and yes "Solar Charge" - My pump is powered by a battery which is Solar Powered). Do I need to have a thermostat wired in that will
stop when the oil gets to a certain temperature. Just to tell you I have a 60L plastic drum (which can withstand alot of heat) which is mounted on a frame which me and my dad made (it looks very professionally done). Once finished it will be on coster wheels and be able to be moved around the place. My pump is solar powered but I will still need access to mains power to operate the "Mix" and "Heat".

Thanks in advance,

Hamish - New Zealand

[gwalker Senior Member Find all posts View Profile Close gwalker]

Re: Fitting a Heating Element

Hi All, I am going to fit a Heating Element to my bio-diesel proccesor....Do I need to have a thermostat wired in that will
stop when the oil gets to a certain temperature.
Hamish - New Zealand

From my limited knowledge.

You don't want to heat the oil more than 60degC otherwise the methoxide will evaporate (65degC)...so you need a thermostat to tell you the temperature (Most people seem to process at at 55degC).
You only need to control the temperature for an hour while mixing the methoxide so you can control the heating element manually by turning the heating element on and off or you can use a thermostat wired in to not let the temp go beyond 60degC.

I'd also consider wiring the heating element in line with the pump so that you can't operate the heating element without running the pump to circulate the mixture.

Also, don't mount the heating element directly to the plastic drum cause it could melt it, but suspend it in the mixture.

my 2cents worth

G

[Hamish Biofuels Forum Newbie Find all posts View Profile Close Hamish]

Re: Fitting a Heating Element

Thank's, I will mount it under the lid with a metal pipe or something, but I will see what my dad thinks of. I might get a thermostat and set it to around
40 oC - That will mean I will have to mix it for around 2-3 hours. I will be looking into buying a fuel filter and connecting it up to my pump (the pump that pumps the finished bio-diesel into a storage container), so that way it is filtered very fine. I am mounting a drill on the drum so it mixers it - Should I have it set to a low of high speed ?.

Thanks Hamish

[quesoburgesa Senior Member Find all posts View Profile Close quesoburgesa]

Re: Fitting a Heating Element

Hamish,

Are you heating the waste oil prior to processing, in order to boil off any water that's in solution? Just curious. I pre-heat mine to about 110 degrees, which I'm led to believe is a necessary step, as the water in the oil prevents the transesterification process from completing.

Just curious.

Justin

[Hamish Biofuels Forum Newbie Find all posts View Profile Close Hamish]

Re: Fitting a Heating Element

Hi, I am not boiling the oil to get off any water because I pre do that. I am heating the water so I can mix in my chemicals. How would I go about a thermostat ? Does anybody know should I have the drill that mixers it set to a high or low speed ?

Thanks Hamish

[Chris Senior Member Find all posts View Profile Close Chris]

Re: Fitting a Heating Element

Hi, I am not boiling the oil to get off any water because I pre do that. I am heating the water so I can mix in my chemicals. How would I go about a thermostat ? Does anybody know should I have the drill that mixers it set to a high or low speed ?

Thanks Hamish

Hi Hamish
What you are using the water for? to mix your chemicals you say?
I do not understand what you mean but let me point out to you that any water in the oil or contained in the materials that you are using will stop the process dead in it's tracks
You will be making Goop not biodiesel
Even traces of it will stop the conversion
You need to have oil with no water in it all your chemicals must be water free no moisture is tolerated by the process
If you are heating the oil to drive the water off, let it cool down to below 60 C before adding your Methoxide and do not use any WATER at all
Cheers
Chris

[Hamish Biofuels Forum Newbie Find all posts View Profile Close Hamish]

Re: Fitting a Heating Element

Hi chris, BEFORE I put the oil in my bio-diesel proccessor I will be removing the water, so there will be NO traces of water. Do you think I should put my drill (which mix's it) on a high speed or low speed - Yea, it's one of those variable drills.

I am in New Zealand and Diesel is currently around NZ$1.18L and 91 Petrol is NZ$1.40L and 95 Petrol is NZ$1.48L, The prices are always changing though.

Thanks Hamish

[Jasper Free from the Majors Find all posts View Profile Close Jasper]

Re: Fitting a Heating Element

Hi.
I have used the Hot water element in my 200lt drum. I got hold of a HWS and cut the fitting out of it, kept the thermostat, fittings and the cover. The rest went to the recyclers. I purchased a new 2400w element from a plumbing supplies shop for about $38. The fitting was welded into the drum and the thermostat is used in conjunction with the new element and the original cover fitted. The thing owes me $38, looks professional and the parts are easy to replace if I have any trouble in the future. Also, if I need to up the heating I could run a 15 amp power point to the shed and increase the power to 3600w unit for another $38 (plus the cost of a new power point).
I have not yet heated a full drum of oil but I am fairly confident it will be OK.
I don't know if this will help you with a plastic tank but I reckon steel is a little more versatile.
Cheers, Chris
Ive put a pic so you can see it with out the cover before it was wired up .

[Tony From West Oz Vice Chairperson of WARFA Find all posts View Profile Close Tony From West Oz]

Re: Fitting a Heating Element

From my limited knowledge.

SNIP
I'd also consider wiring the heating element in line with the pump so that you can't operate the heating element without running the pump to circulate the mixture.
SNIP

G

gwalker,

To ensure that the heater can only operate when the pump is operating, you should have the heater wired to a pressure switch or flow switch in the pump outlet, so that pressure or flow must be present for the heater to operate. If the pump fails, this will prevent the heater from continuing to operate.

Hamish,
You should consider using solar heat to heat the oil. Use a solar water heater to supply you with hot water and pump hot water thru pipes immersed in the oil. This will avoid the need for a high wattage invertor and large batteries for it. A thermostat could be used for the water pump to prevent heating the oil above the BP of methanol.

[Truckdriver Junior Member Find all posts View Profile Close Truckdriver]

Re: Fitting a Heating Element

For those thinking of installing "in drum" heating elements - BEWARE.

As previously stated on another thread; elements have a power to surface area ratio.

Put simply: You can have a 3KW element that is 20cm long with three wraps (80 cm's total or so) or one that is a total of a number or metres.

The surface temperature of the smaller element is obviously much higher.

The higher temperatures concerned
may (will) have an effect on the oxidation and degradation of your oil.

Do NOT rely on convection alone for in-drum heaters! Have your stirrer running during heating or put your heater in-line to your pump circuit.

Td.

[Hamish Biofuels Forum Newbie Find all posts View Profile Close Hamish]

Re: Fitting a Heating Element

I don't need an inverter because the element is for New Zealand Power Supplies (240v). I might have to have the mixer going whist I have the heating element going. Does anyone know If I should have the mixer going on a high or low speed ???

Thanks Hamish

[Guest Close David]

Re: Fitting a Heating Element

To answer the question you have asked 4 times already, It dosen't matter what speed you run your drill mixer as long as it is able to agitate all the oil in the vessel you are mixing it in.

The thing to be aware of here however is because you are intending to mix for hours with a tool that was never designed for such duty cycles, I think to have any hope of the drill lasting more than 1 batch, you will have to run it on low speed. Even then you are going to be putting a lot of wear on the thing and I would budget for a replacement in a very short time. My guess is you are probably intending to use one of the cheap brands of drill so that won't do a lot for its life expectancy either.

It dosen't really make sense to use a drill for hours of mixing while you have a pump sitting there you are only going to use for a few minutes to transfer the BD out of the reactor. You would do a lot better to use your pump for the mixing as it would be designed to be run for hours at a time unlike a drill. Buy one of those cheap drill pumps and swap the components around.

If you don't have enough capacity in your solar system to run the pump that long, either add some more batteries or just plug the thing into the mains power you already have and be done with it.

I think you are going to be buying drills pretty often otherwise and chances are they are going to die in the middle of a batch and then you will have other problems to deal with.