New GL processor problem

[Mickindashed]

Hello everyone. I built a GL processor recently and made my third batch over the weekend. It's basically the standard design with a dickjotec venturi, but I used a car radiator fan and header tank to cool the condensor, a pid for the heater and a settling tank for the wvo with a floating pick up. The floating pick up works a treat - the oil settles for a month or so between batches and by the time I draw off a batch of oil to process it's light coloured and clear.

My demething seems a bit slow, but I'd be grateful for other peoples' views. When I had the bio at 90c the pd condensor was at 22c, which is as cool as I can get it with the fan running at full speed. It took an hour to distil the first 2L from a 90L batch. I use a 2 stage reaction and a 5% prewash.

Also, I bought a 1997 Peugeot 106 to use as a test vehicle while I get the process worked out. After running 1000 miles or so on my first 2 batches ( admittedly they were not full conversions and probably a bit soapy too ) it started to die if left at idle for 5 mins or so. I've changed the filter and had the pump bench tested. The pump is functioning fine. My next step is to refit the pump, drain the tank and see if it runs ok on diesel. If it does I'll try 50/50 with my new clean and fully converted bio and take it from there. Anyone got any ideas what the idling problem might be?

Admin edit: moved this post to its own thread

[Tony]

Welcome to the forum

Demething can take a time, depends a lot on how much Methanol is left, the energy dumped into the mix, the surface area and dwell time of the condenser... many variables.

The car problem - more often than not caused by a blocked filter (is there a pickup mesh in the tank?) or pipework letting in air.  Have you got some clear pipe you can put between main filter and fuel pump to check for bubbles?  Better still one on the return feed to the tank, if it's creamy/bubbly then the pump itself could be drawing in air somewhere (input shaft seal, throttle shaft seal - all popular places!)

[Rossey]

With the car.

There's no gauze filter in the tank.

The first thing to do would be to fit a clear pipe between the filter and pump.
As you may the have the same problem I do, the fuel filter assembly is prone to cracking on these and letting.

What make is your fuel pump?

[Mickindashed]

I've got a bit of clear pipe between the pump and the filter. Just before it dies you see a load of little bubbles going down the pipe. The mechanic who's got the car says that's not the problem - not sure I believe him!

[Mickindashed]

Thanks everyone, it's a Lucas pump.

[greasemonkey]

I used a fan and car rad to cool my condenser. With the amount of methanol fumes hanging around, I was to scared to turn it on..........
How do you get on with it?

You might have to change the filter more than once. I ended up having to drain the tank after my first use of bio. Blocked three or four filters in a row, at about 300 mile intervals. Been fine since I drained the tank.

[Mickindashed]

I started off using a rad without a fan but it was useless. The condensor temp went to about 45c during demething. The fan reduces the temp to about 4c above the ambient temp. I take your point about the risk of running a fan where there might be meth vapour, but I convinced myself the risk isn't a problem since the processor is a closed loop and there are already two pumps running anyway. Plus my shed doors basically open up the whole end of the shed and the eves are open so hopefully the ventilation will be ok.

[Jamesrl]

Unfortunately the standard PD condenser seriously struggles with demeth, you need a multi-cored condenser.

Using a stillhead heat exchanger considerably reduces the load on the condenser.

So a SHEE and a Quad cored condenser will vastly reduce your demeth time and make keeping the coolant temperature down easier.

[Rossey]

Unfortunately the standard PD condenser seriously struggles with demeth, you need a multi-cored condenser.

Using a stillhead heat exchanger considerably reduces the load on the condenser.

So a SHEE and a Quad cored condenser will vastly reduce your demeth time and make keeping the coolant temperature down easier.

Is a SHEE just a standard fphe?

[Mickindashed]

How would I go about fitting a SHEE? The reactor is built around a copper hot water tank. It would be easy enought to make another pd condensor and fit it next to the existing one as a first step towards a quad cored condensor. Food for thought...

Meanwhile I'm running my cdti vectra, which has a dpf, on 15% bio and keeping an eye on the oil level.

[Rossey]

The SHEE is fitted on the vent of the processor before the pd.

Have a look on the wiki there's some pics on there.

[Jamesrl]

It would be easy enought to make another pd condensor and fit it next to the existing one as a first step towards a quad cored condensor. Food for thought...

The multi PD idea has been tried before sadly they don't work particularly well, 4 cores with a common plenum is the way to go.

A SHEE is fitted between the reactor outlet and the condenser input.

[Mickindashed]

Interesting idea to use a heat exchanger, but wouldn't it be more efficient to use the coolant rather than the air in the vapour circuit for the cold side of the heat exchanger? And for that matter, How about just using a heat exchanger as a condensor? Has it been tried?

[oakwoodtv]

I use FPHEs as my condenser three in series its very over kill the middle and bottom
ones never get warm

 

[Jamesrl]

Interesting idea to use a heat exchanger, but wouldn't it be more efficient to use the coolant rather than the air in the vapour circuit for the cold side of the heat exchanger? And for that matter, How about just using a heat exchanger as a condensor? Has it been tried?

You may have missed the point of a SHEE, it's used to heat the returning air/vapour thus reducing the energy required to drive the evaporation process.