Biomass fuel

Anything organic will rot down after a while and be useful in the garden. If its woody stuff I'd keep it separate from other compostable material - I use builders bags for this and usually havie one with wood chippings in - takes about 18 months with those.

It depends on what they mean by "spent biomass fuel" - wood ash roughly fits into that description (too alkaline to use in large quantities)

Apparently its rape, grass and animal waste as far as I can find out from the chap selling it

What does he mean by spent? Has it been in a digester? Could be good stuff...


Digestate | Anaerobic Digestion

It’s the waste biomass fuel, that’s all I know

You could set up a few experiments...

1 grow container with any choice of veg in 100% biomass
1 grow with a 50/50 biomass soil mix
And a compost heap to see if it composts further

I have some beans germinating to see what happens

If it's the fiber from a biogas digester then it could be pretty good. Biogas digesters convert organic materials (manures, food waste, plant waste) into methane ( CH4) so it takes carbon out of the material (reducing it's percentage by volume) but leaves the nutrients in there (slightly concentrating the nutrient value).

The digester is powered by the microbes found in the stomach of cattle which is good at breaking down matter into Methane in anaerobic environment. What comes out of the digester is a sludge that looks alot like sewage (smells like it too) this is made up of the liquor (which is often recycled back to mix with new material to that it reduces water costs) and a fiber (the solid portion of the slurry containing the nutrients that aren't dissolved in the liquer, bacteria, lignin and cellulose).

You might want to find out how this slurry is treated (e.g. ultraviolet or ozone treatment) to make sure that it kills off the bacteria as the gut is not only home to the useful methane producing bacteria it can also be home to bacteria such as e-coli, salmonella, etc. so care precautions may be needed when handling (mind you, same precautions as handling fresh manure, nothing CDC level).

The fiber can be used as a soil amendment, composted down, used as animal bedding or applied as a mulch. If it's been hot composted down then the bacteria shouldn't be a concern.

Re the rape seed waste , the bigest problem rape growers in the UK are facing at the moment is Clubroot ! so it may not be any good for growing brasica.s in ? atbDal

Sounds like Triffid growing medium to me.