Burning rape straw compared to wood

[humblefarmer]

You are basically baling chaff.

Our old baler (NH835) used to do it ok (we used to use it for bedding)

Our current baler (NH 740) has a rotor feed and short stuff just stalls between the pick up and rotor and won't feed. Also had problems with short wheat straw. Rotor can't get a hold of it as it is too short and brittle.

Other balers may be better but most modern round balers have rotor feeds.

I think a lot depends on the combine. Our old JD STS trashed the straw but the new one seems to leave sensible rows which bailed fine and left clean stubles for min till cultivations to follow.

 

[Cowcalf]

Two 5' round bales of Rape straw should produce and equivalent amount of heat to 400kg wet wood. If the straw is dry there shouldn't be too much ash but there will be more than if you were burning wood. With wet Rape straw the biggest problem is getting the fire started. Once underway it should burn fine. Wet wheat straw is hopeless even if you already have a bed of embers. I'm not qualified to comment on the acid corrosion risk burning straw but believe that if a high flue gas temperature is maintained the risk is reduced because the acidic moisture in the smoke cannot condense in the flue.

that would be like buying wood for region of thirty pounds a ton and no processing, sounds ok to me

 

[KennyO]

I think a lot depends on the combine. Our old JD STS trashed the straw but the new one seems to leave sensible rows which bailed fine and left clean stubles for min till cultivations to follow.

If our combine is leaving long rape straw the straw ain't dry enough for burning.

What baler were you using?

 

[humblefarmer]

that would be like buying wood for region of thirty pounds a ton and no processing, sounds ok to me

How did you come to this figure?

If our combine is leaving long rape straw the straw ain't dry enough for burning.

What baler were you using?

Contracted out so not certain but it was a new JD baler last year set To about 40% density. It the driest crop we have bailed so far, between about 8 and 12%.

Maybe we just hit luck last season though? Focus is on linseed and bean straw too.

 

[Cowcalf]

How did you come to this figure?



5 bales would give equivalent heat to one ton of wood according to above and that allows 6 pounds per bale including haulage

 

[woodworm]

I agree with cow calf on this but still plan on burning it, have heard that to though.

How much heat does 400 kg of wood give, assume it's at 35%?

Linseed is the best I have found, burnt 5 round bales in 25 hrs this week, approx 4500 kW from it.

@humblefarmer Your 400kg of wood at 35% mc will give you 1280kWh

 

[glasshouse]

soft centre round bales burn the best

 

[humblefarmer]

@humblefarmer Your 400kg of wood at 35% mc will give you 1280kWh

On that calculation that's 3200 kWh / ton of straw? On the light side perhaps but I suppose 35% MC would reduce this, as you are the wood man round here what would this figure change to if it was drier, maybe 15%?

Bales are bulky and I have and may want to look again at burning other wood based products like shredded pallets etc. Instead. I can dry to the best moisture needed for optimum heat but I don't think the amount of heat by volume will change much though, do you agree!?

 

[woodworm]

At 15% it would be 1755kWh

 

[humblefarmer]

Interesting.

What's the optimum wood based product which gives the most output per volume, which is unprocessed?

Have you anybexperiance in shredded pallets?

Thanks

 

[woodworm]

Torrefied wood pellets would be 2780kWh for your 400kg. Pure energy!

 

[woodworm]

Interesting.

What's the optimum wood based product which gives the most output per volume, which is unprocessed?

Have you anybexperiance in shredded pallets?

Thanks

If its unprocessed, then it has to be logs, and the driest you can get the (on average) will be about 17/18%mc which is similar to the 15%mc chips

 

[humblefarmer]

I like to work by the ton, easier for my little mind, so that's 6950 kW/t - wow!

Cost per ton though? If plans come to fruition I will need to make the decison of cheap fuel which is more time intensive or more expensive which is easier to burn. Not sure how easy it would be to batch burn pellets though as obviously not designed for this.

 

[woodworm]

Torrefied pellets about £250/tonne

 

[humblefarmer]

If its unprocessed, then it has to be logs, and the driest you can get the (on average) will be about 17/18%mc which is similar to the 15%mc chips

So about 4380 kWh / ton? Logs are tricky for me to handle though, even if I might be able to force dry them down a bit

 

[woodworm]

Probably about 4200kWh but there abouts

 

[humblefarmer]

Torrefied pellets about £250/tonne

Ok thanks, 3.5 p / kWh that about ten times more than current fuel source, in a good year.

Was never going to be this easy though was it!

I tried shredded pallets last year @ £15/ t but heat output wasn't worth it. Best stick to straw and keep the arsonists away!

 

[e3120]

You are basically baling chaff.

Our old baler (NH835) used to do it ok (we used to use it for bedding)

Our current baler (NH 740) has a rotor feed and short stuff just stalls between the pick up and rotor and won't feed. Also had problems with short wheat straw. Rotor can't get a hold of it as it is too short and brittle.

Other balers may be better but most modern round balers have rotor feeds.

Ditto the welger, which gobbles everything else up. Also, if it's really dry (=short) it finds all sorts of new corners to collect and obstruct net etc. Did some 2m ones for a burner a couple of seasons ago. Huge amount of stuff in them but if you touched the net they just exploded. I thought it was hard on the baler - had a bearing go and had to deploy the fire extinguisher (AKA juice bottle) PDQ.

 

[humblefarmer]

Ditto the welger, which gobbles everything else up. Also, if it's really dry (=short) it finds all sorts of new corners to collect and obstruct net etc. Did some 2m ones for a burner a couple of seasons ago. Huge amount of stuff in them but if you touched the net they just exploded. I thought it was hard on the baler - had a bearing go and had to deploy the fire extinguisher (AKA juice bottle) PDQ.

When the juice bottle is called upon things can't be going well!

We managed about 150 round bales this season which I will soon find in the straw shed, will see how they are the. But the test bales burnt seemed fine.

It hasn't occurred to me that hestons may be harder to bale up as strings not nets? Bugger.

 

[KennyO]

Need one of these bad boys from oz. baler fed by conveyor out of combine.