Pics and info submitted by ECN Member Alan Belson.

Here's how I solved the unburned-oil and jet clogging I met with in my earlier machines,HERE, to make a reliable and efficient Vegetable Oil central heating burner. I’ve accepted the compromise of blending VO with diesel oil, though the fuel is no longer entirely 'free'. Features of this burner, built from a recycled pressure-jet unit, are- A dual-fuel system, rationalised electrical fuel-heating, a new exhaust gas re-circulating combustion chamber and additional electrical controls, the latter forming most of the modifications.

Alan,
Very thorough job of engineering and fabrication! In the future, you might consider increasing your heat tape wattage to accomplish the VO heating, without the lamps. Many industrial sites use this technique to maintain fluids at elevated temperatures, so it is a proven technique.

I have installed primary and backup heat trace systems to allow for future failure and easy switch-over to the secondary system. Also a variable voltage control, such as a rotary motor speed control makes it easy to adjust for the need of additional heat.

Good luck with your alternative heating system! You set a good example of recycling the earth's resources.

Homer

Just think ... the same folks here who will admire Alan's ingeneuity will sneer at a tuna-can used as a junction box, a soap bottle used to hold a device, and a wood (home-built- panel.

Where are you getting your oil?
Used cooking oil is getting hard to come buy here because so many people are using it. My wife used to have to pay to have it hauled away. Now she barters it out for services. Burger King was selling their oil as long ago as the 90s.

Alan,

Couple of questions:

1) Does the ratio mix of diesel oil to VO change with the level of the diesel in the supply tank?

2) What prevents the VO from pushing the diesel back thru the 15 u diesel filter if the Danfoss pump trips out?

The setup looks good.

Greg, my oil comes from just a couple of privately owned restaurants, who'd otherwise be paying to have it disposed of at the Commune's décheterie. It's mainly fried "fish & chips" oil, with occasional fried chicken, breadcrumbs 'n herbs debris from a pizza joint. No supply problem as yet- just the opposite - I have over a year's supply in stock now but daren't lose my good suppliers...

Larry, the diesel tank's head has no effect on flow rate, which is controlled soley by the gear-pump pressure and the nozzle's GPH rating. The GPH is constant, regulated by a relief valve in the gear-pump, which bypasses surplus fuel back to [in this case] the gear pump inlet. [I have a 'one-pipe' diesel supply, which I omitted to mention in my efforts to keep the blurb to a minimum - see last pic but one, with the existing redundant return line plugged with a spare fire-valve]. The peristaltic pump has a constant flow rate once set, of about 1 liter per hour. It is only a 3.5 watt motor but [tip] it flipping hurts if you stick your finger in the rotor like wot I did!

Gear-pump failure scenario. Good point, thanks and a new note added to the instructions! No fuel then flows to the burner, which would 'flame out'. The Protek valve shuts at 135 psi, so there is a minimum oil pressure. The trachoidal gear set is virtually oiltight unless rotating, so VO would then be pumped toward the diesel tank. But a 'flame out' will be seen by the photo-resistance flame monitor, which will lock-out the LOA Controller, shut down the burner and wait for a manual reset. A lock out also shuts off the peristaltic pump and its solenoid valve. This usually takes a few seconds, but in this case, worst scenario, the photo-cell might 'see' the combustion chamber for half a minute or so while it cools down. Half a minute is only 8cc of VO, [ 2 teaspoons ], but it's enough to warrant a manual flush-out, which would be my normal reaction to a power outage. Flushing out is easy. I have a spare 3-pin Danfoss LE pump plug and can spin up the gearpump independantly to run diesel out of the finger tightened air-bleed nipple at the 'Y' manifold which is just visible under the pressure gauge, [a necessary chore with 'one-pipes', which don't auto-bleed.]

A non-return valve in the diesel line would risk damaging the peristaltic pump gearing &/or its motor windings - or a blown-off VO pipe- [it's only push fit tube] if it has 'nowhere to go', so that option is out.

It sounds like you need a diesel truck
That is what the guys use the oil in around here.
They have some kind of filter and conditioner system in their garage.

Is the diesel over in France close enough to kerosene that you could use kero in a pinch?

Doesn't diesel fuel support fungus or mold? How do you prevent plant life from growing in both the diesel and VO?

Larry

There's a slight difference between kerosene [petrole] and 6 cst heating oil [fouil or mazout] here. For the burner, the problem is kero's poor lube qualities in the pump, so long-term it's not good but it will work. For a car, same problem. I have a full 1500 liter tank of diesel for the burner, but it's not road-duty paid stuff and it's dyed red. Big, big, fines if you get caught with 'red' in your car, strike or not and the 'bloaters' [gendarmes] can detect 1 part in 50,000! I have a nearly full tank of gazoil in the car and an emergency supply stashed in the tractor, so no immediate problem. I'm using my new electric bike to go to the farm for eggs and milk. 15mph - Zooooooom!!
As to bacteria, yes they can be a problem [or a boon, as in the Gulf off Louisiana], choking the filters. But they can't grow if there is no water in the fuel, so I try to take care to make sure its 'dry'.

Kerosene is a lot more expensive here than diesel or home heating oil.

An electric bike, eh?
I'd like to see that!

Alan,

How do you remove the water from the VO? Does the centifuge perform that task?

that's neat!

~S~

Short answer Larry, is yes, in theory! I've learned a lot in the last few months running this burner for real, especially since it's been absolutely freezing and snow-bound here since early November last despite the Gulf Stream. We have now burned about 600 litres [US $700 worth] of fuel at 50% VO. This success has prompted the Accounts Dept [aka Her Indoors ] to release more funds for the next phase of fun!

My routine is to use natural gravity settlement, for two or three weeks minimum, in 20 litre plastic jugs kept outside. These are then wiped clean & kept on the warm floor of the ute room for a week to warm the oil so it pours nicely. The crud and water are mostly then at the bottom. The jugs are decanted carefully into the separator pan, trying not to introduce any crud, water or crystals of fat. Spun oil is 'dry', as most water separates from the oil and is then pumped through a 20 micron cotton wound filter directly into the heated oil vat. This removes floating debris that a separator won't remove. 20 microns is about 0.0008" [8 tenths of a thou' inch] which is plenty ok for a pressure jet nozzle, but as belt 'n braces, I have a 10 micron paper element filter fitted just after the VO and diesel are mixed.
All this work is my weekly chore and takes about an hour or two to refil my oil tank. Mostly, I'm just watching the pumps run, swilling coffee and smoking some baccy while H.I. listens to The Archers on the BBC Steam Wireless!

Water is not a serious problem in small amounts. Actually, a 30% water/oil emulsion will burn nicely! In a burner, it improves combustion and reduces pollutants, provided it's emulsified.

In fact, This Years Project is to switch to an emulsion of oil and water as fuel instead of a diesel/vo mix. I'm thinking of switching to Used Engine oil, as it will be far easier to filter than VO and can be stored 'cold'. A 30% water emulsion will have a viscosity less than diesel oil at ambient t, so preheating may be not needed. My garagiste is keen- he's got a couple of thousand litres in stock which costs him $$$$ to have removed. All the fuel is then free, except for a few teaspoonfuls for ignition and flushing. To this end, I just imported a new German Hansa Blaubrenner burner from Hamburg, which is similar to my 'homebrew', but it's not only beautifully built and more controllable, it runs at 360 psi [!]- & it also has a CE mark so my fire insurance will be valid ! I also now have a new exhaust-gas analyser, so I can set up burners accurately. It's an earner too!

More anon hopefully in the summer after some experiments if that's ok with the forum? I know this is not strictly core electrical.

2 fr-r-r-r-rostbitten thumbs up Al

this 'ol sparky's freezing his tookers off , and loves to come home to a hot story

I burn wood btw

.....but as efficently as i can

~S~

Old post but it seems it's the same everywhere,State of California was stopping all diesel fueled trucks & pickups at roadblocks to check for off road fuel & have heard it's a $10,000 fine if you have the misfortune of getting caught w/ red dyed fuel in your tank.

Please keep posting on the progress as it has been quite informative & enjoy reading it.

Alan,
Thanks for sharing this project with us. As you solve problems and move to the next phase it becomes a continuing story that may enable someone else to install a similar heat source for their home or business. It is interesting to see each step that you take.

You mentioned a concern about fire insurance. I have dealt with that by installing my remote controlled pellet burner outside in an insulated shed with non flammable siding and a metal roof. I pump hot water through insulated piping underground to a coil that sits in my interior air handler which is also connected to a heat pump. If the pellet stove fails the heat pump takes over. Different installation but similar concern about insurance.