Laurence Palmowski, Dr.
Johannes Müller
Institute of Mechanical Process Engineering, Technical University of Braunschweig, Postfach 3329, D-38023 Braunschweig, Germany
Abstract:
The rate-limiting step in
anaerobic digestion of organic solid waste is generally their hydrolysis. A
size reduction of the particles and the resulting enlargement of the available
specific surface can support the biological process in two ways. Firstly, in
case of substrates with a high content of fibres and a low degradability, their
comminution yields to an improved digester gas production. This leads to a
decreased amount of residues to be disposed of and to an increased quantity of
useful digester gas. The second effect of the particle size reduction observed
with all the substrates but particularly with those of low degradability is a
reduction of the technical digestion time. It enables a harmonization of the
digestion of heterogeneous inputs and the possibility to reduce the digester
volume without lost in the gas production. Furthermore, the particle size of
organic waste has an influence on the dewaterability after codigestion with
sewage sludge. The presence of organic waste residues improves the
dewaterability measured as specific resistance to filtration but this positive
effect is attenuated if the particle size of the solids is reduced.
Origin:
L. Palmowski, J. Müller
(1999). Influence of the size reduction of organic waste on their anaerobic digestion, Water Science
and Technology, 41(2000)3, pp.155-162 and IAWQ II. International Symposium on
anaerobic digestion of solid waste,15.-17. Juni 1999, Barcelona, Spain,
Preprints Vol. 1, pp. 137-144