Green Dragon Sustainable Fuel

[Neil WyattModerator @neilwyatt]

Following on from the ecoal article…

This came up on Facebook from the North Yorks railway… ‘green dragon’, a sustainable fuel made by pressing waste from the rapeseed oil industry into briquettes.

https://fb.watch/HM7Tf7Z2XY/

Neil

[Nigel Graham 2Participant @nigelgraham2]

It certainly seems effective though I wonder if its calorific value is only about that of wood (roughly half that of good coal).

It seems rather a smokey fuel but that might reflect the combustion conditions in a vertical boiler. Have they tried it on the larger locomotives with brick arches in the fireboxes?

To be fair I didn’t get the best out of the video because my PC no longer plays the soundtracks, and the text below the images ended in mid-sentence.

[Michael GilliganParticipant @michaelgilligan61133]

https://sunderlandheritage.org/projects/green-steam-at-ryhope-engines-museum

MichaelG.

.

Ref. https://ryhopeengines.org.uk/history

[Nigel Graham 2]

On Nigel Graham 2 Said:

It certainly seems effective though I wonder if its calorific value is only about that of wood (roughly half that of good coal).

I think for the Heritage steam railways, pumping stations etc calorific value may be less of a problem if the cost and availability of the fuel is more beneficial. More of a problem would be storage of the large quantities needed as I would imagine it has to be kept dry.

Andy

[Michael GilliganParticipant @michaelgilligan61133]

Ferinfo.

https://greendragonfuel.co.uk/our-solid-biofuel-briquettes/

 

MichaelG.

[noel shelleyParticipant @noelshelley55608]

Interesting but the smallest size is 2″ square and 3″ long so it won’t even go in my 7.25″ engine. If firing with a normal shovel then it’s an option that may work once experimentation has arrived at the best way to use it – provided the boiler design can efficiently burn it. Rape oil is a good fuel for certain OLDER diesel engines and was a fuel experimented with by Herr Diesel in the late 18th century, though some concessions must be made.

Does the the smoke smell of barbecue ?   Noel.

[duncan webster 1Participant @duncanwebster1]

Pedant alert, Rudolph Diesel was late 19th century.

Chap in our club ran his van on cooking oil. It smelled like a chip shop if you were following. Not to be attempted on modern diesels. Mine even had a warning not to use bio diesel. When the big stand-by diesels at a place I worked at were taken out they were converted to run on chip oil. They were old, but had done very few hours.

[Martin Johnson 1Participant @martinjohnson1]

The ASTT has done quite a lot of work in evaluating coal alternatives for steam engine use.  Green Dragon Mk1 had major problems in producing poisonous smoke with fantastic headache inducing properties.  I believe the blend has been tweeked to eliminate that problem.

However, current state of the art is that nothing equals good coal, generally needing requiring more of a more expensive fuel.  Feasible for hobby use but a problem when trying to run heritage railways already on tight financial margins.

Like all good research projects, “Further work required”.

Martin

[not done it yetParticipant @notdoneityet]

Did I read 17% rape seed oil?  That is not usual – it’s a bit more than twice the residual oil after hot pressing, I believe.

Cold pressing would be wasteful on oil extraction, but also leave behind the less combustible triglycerides.

The advertising hype (of not much more needed than burning coal) seems a bit off.

Buying a lorry load in 1.25 tonne bags/pallets would depend on how large the lorry was, wouldn’t it?  Appears to be 20% VAT for most?

[duncan webster 1Participant @duncanwebster1]

Son in law drives on the TR. They have experimented with ecoal and experienced the toxic smoke issue as well, not sure which brand.  They now use a mix of real and ecoal, as ecoal on its own didn’t produce enough heat.

The whole thing is a government created farce, unless of course imported coal produces less CO2 than Welsh coal. The heritage sector uses 20,000 tons a year, not trivial, and digging it up (opencast) would keep some people in a job, which means they would pay tax as well as helping balance of payments.

[duncan webster 1]

On duncan webster 1 Said:

The whole thing is a government created farce, unless of course imported coal produces less CO2 than Welsh coal. The heritage sector uses 20,000 tons a year, not trivial, and digging it up (opencast) would keep some people in a job, which means they would pay tax as well as helping balance of payments.

I’m conflicted on this, given my professional background. I can see both sides of the argument and I honestly don’t know what the right balance is.

Obviously the ideal solutions is if some sort of biowaste based product can be devised that truly delivers a satisfactory performance.

[howardbParticipant @howardb]

The killer for this biofuel is that it more expensive than steam coal, and it’s just a waste product.

“Steam coal is still available and although it is expensive it is currently cheaper than Green Dragon”

 

[martin haysomParticipant @martinhaysom48469]

just another eco con. it cost more and its not as good.

[noel shelleyParticipant @noelshelley55608]

• Like most alternative fuels they will be more costly and not work as well, the more so when you factor in things like transport and all the other things involved in it’s production or disposal of waste generated.  Noel.

[howardbParticipant @howardb]

When we moved to France in 2009 we didn’t have local contacts for seasoned firewood,  so with two woodstoves to heat the house we ordered a pallet of compressed wood logs, made from sawmill and wood manufacturing industry waste – like these.

https://www.boisbuchemolinario.fr/product-category/bois-compresse/

Widely promoted as being ecologically superior etc.

We found that to keep the house anything like habitable in early 2010 when we had 12″ of snow, we had to be constantly stoking the stoves with these and ended up using up the  tonne pallet and had to order more.

I don’t know if this type of fuel is on sale in the UK or if anyone on here is using them.

[Nigel Graham 2Participant @nigelgraham2]

Note that they produce rapeseed oil as boiler fuel itself, claiming similar calorific value to coal.

The company’s web-site does not tell us the briquette’s calorific value, but recommends using those 2 – 3 times the average size of the coal your would normally use.

For a full-size railway locomotive the recommended* size of the coal was man’s clenched fist; so ‘Green Dragon’ briquettes about the size of a house-brick. In a full-size locomotive boiler (I’d include traction-engines in that.)

Note that is lump size and not a guide to performance; but lump size governs ignition and combustion efficiency.

For a miniature clearly we’d need break or cut the blocks to suit the engine; but I’ve not noticed much talk among model-engineers about ideal lump size, even of coal. Some I know imagine that as long as it goes through the firehole it’s right! So are these ‘Green Dragon’ briquettes amenable to being cut or broken or would they just crumble into “sustainable slack”?

We might also consider the safety of its fumes, as driving a miniature engine puts us close to its exhaust. Though coal is not exactly healthy, with at least CO2 and if not burnt fully, some CO as by-products; and sometimes SO2.

 

As an experimental alternative to coal for our miniatures, what of charcoal?. Readily obtainable as barbeque fuel, mainly carbon, it produces a fair amount of ash but not clinker, and if I understand the tables ** correctly is comparable with coal in heating value. It was used for smelting iron until the development of coke.

A miniature burning low-density charcoal might be more prone to ember-throwing, needing attention to spark-arrestors.

 

Critical to trying anything other than coal, and this is made on Green Dragon’s site for its own fuel, is having to modify firing technique to obtain the best from it. It could even be that those who, as Doug Hewson shows us, build their locomotives with properly-sealed, damper-fitted ashpans below rocking grates, have the advantage because they can control the firebox conditions closely.

(A traction-engine’s firebox is similar in this regard, and a damper is normal on a model TE if only because it is visible, but fitting dampers to miniature locomotives seems a recent development.)

 

*By the BR-issued, Transport Commission’s handbook for steam locomotive operation.

** http://www.engineeringtoolbox.com

[noel shelleyParticipant @noelshelley55608]

A steam generating boiler will be designed to burn a given fuel, be it coal, oil, wood, gas, sugar cane waste or even straw. If one wants to use a fuel for which it was not built there will be consequences which may be just poor steaming Etc but could damage or destroy the boiler. If one is building a scale model then the design may well be unable to accommodate a different design of boiler, then what does one do ?

The amount of fuel burnt by both the heritage and model fraternities will make not a jots worth of difference to any climate change, is it just good PR ?  Ah well.  Noel.

[Nigel Graham 2Participant @nigelgraham2]

For solid fuels the main differences for different fuels seem only in grate proportions.

Studying an engraving of a portable-engine fitted for straw-burning the only significant difference from the more standard coal-burning engine was a special chute arrangement for feeding the straw into the firebox.

Locomotives have been converted from coal to oil-burning without major structural alterations. I think that is so on some of the Welsh narrow-gauge lines.

Sherborne Water-works Museum’s sizeable vertical boiler is seems happy enough with scrap wood as fuel; same with the portable-engine used at Weston Zoyland purely as a steam-generator to power that museum’s assorted steam-engines.  These two boilers would have been designed primarily to use coal. Although of course none of the engines are worked hard.

I can’t see how changing the choice of fuel could damage or destroy a boiler. The most I would expect would be poor steaming; though some might be more efficient. Solid fuel boilers are not very efficient at the best of times.

 

Using a different fuel in a miniature may be more difficult thanks to the small size of the firebox, and on many locomotives open ash-pans without dampers. It would be a matter of experimenting – as it is in full-size in fact. I think a few model-engineers have used bottled-gas or oil, needing more extensive modifications but not to the shell, and not completely new boilers!

It should make no difference to the boiler tests, if the only changes are to the grate and ashpan, and perhaps replacing the firedoor with a plate holding oil or gas jets. It’s still the same pressure-vessel.

[BazyleParticipant @bazyle]

I have seen a member of St Albans running his 040 on briquettes but only down his garden not pulling passengers.
For a 5in loco I recommend nothing smaller than a marble as even that burns down to dust that clogs the firebars. However for some time normal coal-merchant domestic supply has been smaller as it is designed for auger feed boilers, not open fires and engines. ‘Coalite’ and similar processed coal for smokeless zones is better because the coking process produces good sized lumps – about tangerine to apple size.
Charcoal is no good as it has no ‘body’. I always suggest people starting their loco fire go from wood straight to coal forgetting the charcoal stage that seemed to be popularised in the first century of model engineering as a hobby.

[Andy StopfordParticipant @andystopford50521]

I saw a recommendation here (a couple of years ago at least) that due to its tiny firebox, Len Mason’s ‘Minnie’ traction engine was near impossible to fire with coal, and most people used charcoal.

When the time came to light a fire in mine, it did, indeed, perform badly with coal.

I swapped the grate for a rosebud-type (and changed to a smaller blast pipe nozzle) and it now works well on coal*, though it certainly needs a combination of wood and charcoal to get it hot enough for the coal to ignite properly.

There are some photos of Fowler straw-fired traction- and ploughing engines in “The Story of the Steam Plough Works” by Michael Lane. Some of these had, apparently, a mechanical straw feeding apparatus to keep up with their insatiable appetite for fuel, spark arresting chimneys, and modifications to prevent the grates clogging up.

The same book mentions an engine destined for export to Patagonia which was designed to burn llama dung.

Perhaps this is the future.

 

* Welsh Steam grains

[Nigel Graham 2Participant @nigelgraham2]

Llama dung… Not sure I’d want to try driving miniature engine burning llama by-products, or common-or-rose-garden ‘oss muck come to that, for obvious reasons!

 

O.V.S. Bulleid designed a peat-fuelled locomotive for the Irish railways. I don’t know how efficient it was.

[duncan webster 1Participant @duncanwebster1]

Burning llama dung sounds dangerous, likely to be attacked by militant vegans

😜

[NealebParticipant @nealeb]

There is a field near me with a couple of llamas in it. Maybe a quick visit with scoop and sack is called for…

[Nigel Graham 2]

On Nigel Graham 2 Said:

 

I can’t see how changing the choice of fuel could damage or destroy a boiler. The most I would expect would be poor steaming; though some might be more efficient. Solid fuel boilers are not very efficient at the best of time

Devil’s advocate:- At a power station steam turbine testing job I was in India, the customer had supplied samples, at tender stage, to the boiler contractor (ICL) which were 10% ash. When I got there to do the turbine testing, ICL were there, rebuilding the boiler. The water walls had been eroded away in places. Turns out that the customer was running coal with 40% ash (probably higher than specified moisture as well). The result was more fuel, higher velocities in the boiler and greatly increased erosion, leading to boiler leaks after less than two years of operation.

Hopefully that’s unlikely in the modelling fraternity, but moving to a less energy dense fuel probably does need thinking about and experimentation.

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