Problem With Eco-Friendly Biogas Powered Truck

will your pigs eat rose petals?

Hello HUX

Thank you for your interesting suggestion.

I have tried your idea, but without success.

It does appear that whatever pigs eat, the aromatical value of the output is the same - offensive to anything except other pigs.

Kind Regards....

Since you've actually got this thing running (kudos) you probably already know more about it than by far the majority of us but I will throw out a couple thoughts. Can you tell where the offending smell is coming from? Maybe a less normalized nose could tell. Does the digester leak gas or have an excess pressure release? Is the smell the engine exhaust? Is there spillage on your truck as a result of charging? Narrowing down the worst offender is maybe the first step to improvement.

Hello DaveB

Thank you for your valued suggestion.

The main problem appears to be the exhaust fumes.

Whatever the input, the exhaust aroma reflects the original manure source.

It is similar in nature to the biodiesel produced from used restaurant oil, where as a vehicle drifts past, the normalised nose is able to ascertain where that oil came from, because of the particular "flavour".

On-board "spillage" is carefully minimised, and because the system is not a high-pressure one, there is no need for the usual excess pressure release.

Kind Regards....

Hi Sparkstation,

If my late good friend was still alive I would ask him for you but he died some years ago all too early.

He had a Doctorate in pig shit and I am not pulling your leg here, he really did.

My knowledge of the offending smell, or aroma noise as we call it in my household due to my frequent farting, is limited to the fore mentioned eloquent release of digestive gasses.

However I do know that if some smell is bad to people and persistent to the point it cannot be prevented, they often "mask" or "dilute" the offending smell with a "counter" smell. The idea is like noise cancelling, the smell that is used to mask is not so much of a smell itself, rather an anti-smell for the one that is bad.

Look into the theory of ester manufacturing and ester compounds. Maybe that could help you with your vehicular flatulence.

Good luck.

Greetings Sparky!!

Check out items 7-8 on this web site:

http://nationalhogfarmer.com/mag/10_steps_manage_odor/

I hope this would apply to a digester!!!

Cheers Gary

Hello messager

Thank you for your interesting link, which shows different methods of trying to "hide" offensive odours from a large piggery.

The problem for my truck appears to be in the exhaust gases, not at the digester stage, because the system is a low-pressure one, running in an on-demand gas production arrangement.

Thank you for your interest.

Kind Regards....

Hi Sparkstation

We mucked about with small diesels (Listers) way back with them running on peanut oil, then sunflower oil. My recent employment saw us fiddling and farting (oops) about with biofuel on a commercial nature in boats. One thing they all had in common was the various flavours and smells from the exhaust. Quite pleasant but off-putting. Is this your dilemma also? Can you add some bacon extract to the brew, it should improve the smell.

One good thing about it is that you are on the other side of the ditch from us and the wind is in our favour.

I have read your articles with interest for a while, please keep them coming

Hello skippy

Thank you for your much-valued observations.

It is fortunate that I live in one of the more windy countries of the world, also as you say, being rather isolated and downwind from your kind self.

As Australia has feral camels, kangaroos, plenty of sheep and rabbits, perhaps you would be interested in a kitset, once the snags of the present system are "ironed out".

I should point out that kangaroos are in short supply in these hallowed isles, and in consequence, I have not at present been able to experiment with kangaroo ordure.

Of course this could not be imported from your Country, either, due to quarantine restrictions.

Kind Regards....

I used to be the Shooting Times expert on dogshit, and with a position like that, any career move has to be down wards. Graduating to commercial cooking, we found that even the most discriminating customer who would normally frequent establishements specialising in vast bills, could be enticed by the smell of frying onions in butter, and to sell your house, the smell of roasting coffee beans is worth at least as much as an indoor heated swimming pool.

So if you went for pusher prop power, and first stage engine cooling was by twin plates one with coffee beans, and the other with onions in butter, they might start saying yeugh, but as you left, they would be in a state of olfactory joy.

Had you thought of using entire male bovids byproducts perchance.?

Sparky- Why does the digester have to be on the truck? I thought with these units the gas was captured and compressed and condensed and then put into a fuel tank like a propane powered vehicle. You must be using a lot of truck just to haul the digester. Also, try some gypsum (the white stuff in sheetrock) to mellow out the manure before you put it on the fields.

Hello mike k

Thank you for your valued suggestion.

The wasted energy, high electrical power input to run the compressor, and cost of the actual compressor needed has precluded me from using the biogas in the usual manner of compressed form in gas tanks on the truck.

I have done my sums.

Furthermore, such gas tanks/gas cylinders, being high pressure vessels, must be individually numbered and certified, along with the full installation, then all must be further certified on an on-going basis, each six months by an official Government agency, for the complete unit (Truck, plus gas tanks and pipework, controllers and all), to be allowed on public roads and highways.

The requirements are thus quite stringent, along with the associated fee structure, and my truck presently works quite OK on the principle of "on-demand" gas being supplied at low pressure from the on-board manure digester.

In this application, I truly consider that low-technology is more suited, rather than using high-level technology, plus all the Governmental restrictions which go with that.

The advantages of having highly compressed biogas stored in on-board cylinders, are useless if I run out of gas before I get back to the farm, to replenish the gas supply.

Here in New Zealand we have plenty of cows and sheep, thus in an emergency, if I run out of manure, I just collect some from the nearest field which contains grazing herbivores, shovel it in, and wait a short while for those microbes to work and produce more biogas, then, once again, I am on my way, fuelled very cheaply, but perhaps with a slightly different aroma wafting along in my wake.

All suggestions are welcomed, thank you.

Kind Regards....

"Furthermore, such gas tanks/gas cylinders, being high pressure vessels, must be individually numbered and certified, along with the full installation, then all must be further certified on an on-going basis, each six months by an official Government agency, for the complete unit (Truck, plus gas tanks and pipework, controllers and all), to be allowed on public roads and highways."

The government, anywhere, seems to be more of a roadblock to progress than a help. Politicians love control.

Perhaps an activated charcoal filter for the exhaust would help.

Gosh! I was thinking about it and what about silica grains which are also known for their odor deterrant effects too? Probably that will do it...

Allset Sparky Buddy take it easy now and we'll stay in contact later then by CR-4.

Idling Throttle,

MC

I think the problem is in the gas coming from the bio-generator. The bacteria that convert the wast matter to methane also produce other gases. If you could filter out the hydrogen sulfide and other impurities as it leaves the generator I would bet the exhaust from the engine would be much less offensive. Of course this is all gust a guess. ;)

Hi Sparkstation,

I have heard that if you pass your gas through iron scrubber it should take off the hydrogen sulfide which create the bad smell.

Good luck