[Stoves] locally produced pellet

[Crispin Pembert-Pigott]

Dear Andrew

>...and I have read about Shimada screw presses but I am not familiar with
mechanical piston presses other than one which made 50mm pucks from sawdust.


The first machine I worked with was in the early 80's and it made 60mm
extruded cylinders that were broken off at about 12" length. As you said,
they were distinctly layered and lignin bound and quite strong. They
collapsed if allowed to get wet but burned reasonably like wood if kept dry.

The piston was connected to a large steel flywheel which ran at perhaps 240
RPM. Its cavity was side-fed by a screw feeder perhaps 150mm in diameter.
The single motor was 60 kW.

The raw material was planer shavings and sawdust from a clothes peg and
match making factory. It turned out to be sensitive to the amount of fines
in the mix and highly sensitive to the moisture content. It was much more
difficult to run successfully that anticipated.

It was run as a social development project with the intention that the
product would be given away as a firewood substitute. The impacted the
enthusiasm. I think for a while they tried unsuccessfully to sell 50 kg bags
of the stuff at a low price.

Regards
Crispin