Monday, July 8, 2019

Ecofest at Ulverstone: The Case for Biofuels in Transport and Power Generation



Renewables are the flavour of the month with a broad consensus in the scientific community that our continual reliance on burning of fossil fuels is the road to perdition. Resulting climate changes through increased levels of greenhouse gases will probably destroy civilisation within the projected lifetimes of many people alive today and set in motion unstoppable, drastic changes endangering or exterminating most life on earth in the longer term.

We understand the mechanisms, some of which are not rocket science. You can check out the behaviour of salt water at the poles in your own freezer with a thermometer. Sea ice is fresh because salt water freezes at a lower temperature, separating out the salt which falls as super saline, super cold and oxygenated water into the ocean deeps and makes its way around the world ever so slowly, stabilizing temperatures on the planet and allowing marine life in the ocean depths. It takes no great leap of imagination to work out what will happen in the deep ocean should the sea ice and polar currents be disrupted by fresh, light meltwater and fail.

The major engine of heat transfer becomes the atmosphere with super cyclones and a 'storm of the century' on a weekly basis. As for marine life think of an aerobic biology shifting to an anaerobic one. Fish can live only in the surface waters aerated by wave action. And in the depths without oxygen the element of choice for metabolic activity goes to the next line on the periodic table, which is sulfur and that implies a whole different set of organisms. Think rotten eggs but hydrogen sulfide only stinks in low concentrations. At higher ones it is undetectable, other than by falling over dead like the coal miner's canary. Sulphur being much in demand, the concentration in water drops steeply.

A biodieseler I know applied to the government for $300 thousand to set up and produce biodiesel from algae. They were intrigued and offered to match his own contribution of $150 thou and he was highly offended. I have no idea where he intended to grow algae in quantities – it would take large networks of channels of wastewater and stagnant lakes, none of which are available in Tasmania. His plan was motivated by a figure for oil production in algae which can produce up to 45% oil by weight of dry matter. This is far better than a crop like canola. I argued that he would never be able to grow and maintain a pure strain outdoors that would match up with a figure like that – algae is like any other plant and it is in the interest of the organism to put its efforts into cellulose, starch and sugars. But it seems I was wrong, research suggests the only criterion is maintaining a low sulphur level, which may be difficult in our world but is the rule in seven dead oceans like in Bob Dylan's song 'A Hard Rain's Gonna Fall'.

So this is the reset button. The plankton have gone and been replaced by massive blooms of algae fertilised by the rain-eroded topsoils of the planet and they will fix the CO2 we have so thoughtfully liberated from fossil fuels. When the algae dies it sinks into the dead zone and falls to the bottom unprocessed by bacteria or any living thing to be once again sequestered as oil shales which cannot be laid down in our familiar world which sequesters CO2 as limestone via coral polyps in oceans and vegetation on land. (The reefs are coming to an end too as we saturate and thereby acidify the oceans with CO2.) But the shales are here now, a relic of the great Permian die-off, proof positive it has happened before. So go for it kiddies, there are these fossil fuels laying around; free energy for the taking. So why should we consider 'renewables' like vegetable oil and ethanol as motor fuel?

The short answer is that we shouldn't. During the big global oil price shock President Bush worked to make America independent of the gouging Saudis. To this end ethanol plants were built, midwest maize growers subsidised and ethanol content mandated in petrol. The price of maize rose with the increased demand and even the Mexicans got into the act shipping their local staple northwards which led to food shortages and riots in Mexico City. Fermenting maize into ethanol returns about 30% by weight and if an SUV takes 70 litres in the tank, that has required about 200 kilos of maize which is a year's ration for a poor Mexican family, all for your one wind-in-the-hair long holiday weekend. Truly these things are the cars that are eating the world.

And there are other options that become useful in times of crisis. My neighbour during WW II was too young to enlist, but worked on the home front growing and delivering potatoes to the dock in Burnie. The truck had a petrol tank but as much of the driving as possible was done on producer gas. Silver wattle charcoal was burned in a vessel behind the cab with restricted air supply and water sprayed into the flames. Carbon monoxide and hydrogen were produced as the oxygen was stripped from the water and along with CO2 was sucked into the manifold giving just about enough power to help the heavily laden vehicle get to the coast, freewheeling as much as possible. When he came to a hill he would give it a judicious dose of petrol to get to the crest and of course the return trip uphill was made with an empty vehicle. But never underestimate the insanity of our leadership, this is not dead. 'Blue Hydrogen' is now on the lips of coal enthusiasts. We can keep mining and burning brown coal and similarly separate the combustion products with special membranes, converting it to clean hydrogen fuel which the Japanese want to buy as long as it is made somewhere else. Unfortunately the atmosphere is common property and 'somewhere else' doesn't exist anymore.


Biodiesel from waste restaurant oil(which is what this is all about)

Biodiesel is made from vegetable oil heated with methanol and a catalyst in a simple process – a colorimetric titration is done to work out how much fatty acid has been produced by oxidation in the fryers. A calculated amount of Potassium hydroxide, (usually 13 grams per litre of oil) is mixed with methanol (20% of the oil volume) to produce a poisonous liquid called methoxide. Added to dry 60 degree C veg oil in a processing tank with a conical bottom it raises the pH of the mix to 8.3 which is where the reaction takes place. In an hour of stirring the heavy glycerol fraction is stripped from the fat molecule (triglycerides) and replaced by the methanol. Next day the byproduct, a brown syrupy mix of glycerol, excess methanol and potassium is removed through a valve on the bottom of the processor. The biodiesel is clear yellow, about as thin as diesel or sewing machine oil and has a sweet smell. It is then washed with water three times and dried with a heating element and I add a biocide because it is quite digestable by a number of different organisms that can turn it (over years) into asphalt and acids which destroy fuel systems. Compared to dino diesel it is quite palatable, smells a bit like fish and chips and the dog needs to be restrained or he will drink the stuff.

Animal fat may also be used. I don't get this any more because everyone has gone into blends of canola with palm oil. Bio produced from fat has a couple percent more energy but starts to coagulate at about 5 degrees as opposed to 3 degrees for oil based fuel. It is also rich in stearates which are a fatty chemical with a very high melting point that coagulates on metal surfaces and in fuel filters and is relatively difficult to shift.


The Economics of Biodiesel

This doesn't come close to being a viable candidate to save the world. Do-gooders in the European parliament mandated a couple of percent biodiesel at the European pump which didn't do much more than motivate the destruction of rainforest in Malaysia, Borneo and Indonesia for oil palm plantations. That's not to say they weren't already motivated, logging companies were happy to flatten the country and ship the valuable timbers worldwide. If you want some moral order and a few jobs now you have to pay for it, and we here in Tasmania host one of the culprits; Ta An, subsidising their veneer peeling operations of supposedly regenerating sawlogs to the tune of 20 to 30 million dollars a year. It is an odd situation when you have to pay outsiders to take your natural resources, locals had actually been paying out for them for decades. It is also odd that our desperation co-exists with plenty like ….Free Energy. Used vegetable oil is a liability for restaurants and they are happy to give it away but even if it all went into the insatiable guts of the Cars That Eat the World it wouldn't provide transport for very many families. And since manufacturer's guarantees on modern diesel cars are void if you fuel them with biodiesel, popularity has dropped off and repairs to common rail fuel systems are exorbitant. Should you be so foolish as to try and start such a vehicle on a freezing morning with a tankful of coagulated biofuel the repairs may well cost more than the value of your car.

But I use it in a little common rail Fiesta with no problems, simply by fueling it 50/50 with ordinary diesel in cold weather. Recently I checked the EGR valve while working through some computer generated error messages/limp modes etc. The EGR was pristine after 100 thousand k's on biodiesel, no coking at all which is better than any dino powered engine I have seen. The error message read 'Low fuel pressure stop engine immediately' and 'Massive Fuel Leak seek help from your friendly dealer' who charged $130 to just to read the computer, deleted fault messages and sent my wife home with the admonition to bring it back in if the message comes up again. I bought an interface on the net for $40, downloaded a free Ford software program (not Ford's) and started replacing random parts, still cheaper and far more effective and certain than another trip to the dealer. The messages should have read 'Change Fuel Filter'.

Naturally the reader wants to know how much does this stuff cost to produce. It used to cost 30 cents a litre and now it is closer to 40 cents. If there was road tax payable it wouldn't be worth your time. So it is only a freebie in our affluent society. Everywhere else in the world people cook like we do at home, just enough oil to grease the pot or pan and it all disappears. In Asia biofuel is made from waste oil which costs to obtain. After all, it could very well be cleaned and filtered and sold back out on the streets to the food industry. Furthermore you can burn uncatalysed clean dry vegetable oil in your vehicle, the hitch being that you have to have a separate diesel tank as the veg. oil tank has to be heated to 80 degrees with a heat exchanger from the cooling system before you can shift the engine away from diesel fuel and similarly you have to purge the pumps and lines with diesel before you shut the motor down. And you have to do your own mechanical work because professionals don't want to deal with sticky and incomprehensible 'grease cars.'






The unified processor/washer dryer during construction complete with agitator on top. The next image is my Mark 1 processor with all the supporting supporting gear, methoxide mixer on bottom right, wash/dry tank and in foreground the little blue primary oil filter on left. For a final filter I use a water filter with cleanable element.


There is no point in my going into the details of a processing system. You can buy a new one made of plastic for 10 thousand dollars or make it in an old converted oil drum or discarded hot water cylinder for some hours of your time and a few welding rods. Plans are everywhere on the net, try Journey to Forever and Biofuels Forum is an Australian site that will answer all your questions although it is peopled to some extent by rank amateurs who have been sold some pup – like there might be a shortcut that omits the water wash by throwing plaster of Paris into the mix or a zeolite filter. Anyone who has tried unwashed bio generally loses in the end as caustic soda is very hard on your expensive (aluminium) injection pump, while water if not completely removed will destroy the moving parts of case- hardened superclose tolerance steel and there is an old appropriate adage “If it ain't broke, don't fix it.”

This and more is published on georgesmileyblog.blogspot.com

Best wishes

GS