Converting Waste Agricultural Biomass into a Resource - UNEP

In mechanical terms, the reactor technology is remarkably simple and robust.
The rotational speed of the cone is only 300 rpm and after more than 1000
hours of operation in the current 250 kg/h pilot plant signs of abrasion or wear
are absent
Scaling up of the rotating cone reactor is possible by increasing its diameter.
For capacities, which require a cone diameter larger than 2 meters, stacking
of multiply cones on a single axis leads to the lowest investment costs. This
conventional approach is also encountered in centrifugal disk separators or
rotating disks contactors. With these options all pilot plant capacities between
2 and 100 ton/hr can be served.
Detailed Process Description
Biomass particles are fed near the bottom of the pyrolysis reactor together
with an excess flow of hot heat carrier material such as sand, where it is being
pyrolysed. The produced vapours pass through several cyclones (not shown)
before entering the condenser, in which the vapours are quenched by recirculated
oil. The pyrolysis reactor is integrated in a circulating sand system
composed of a riser, a fluidized bed char combustor, the pyrolysis reactor,
and a down-comer. In this concept, char is burned with air to provide the heat
required for the pyrolysis process. In this case the plant is self-sustaining. Oil
is the main product; non-condensable pyrolysis gases are currently flared-off,
but application in a gas engine is foreseen. Excess heat can be used for
drying the feedstock.
Main Products
Gas, bio-oil and char
Operation and Maintenance Requirements
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