298 94 307/02 Untersuchungen zum Stand der Umsetzung des ...

Teil 3 Seite 10-10
largely converted into the energy carrier biogas in a subsequent biogas reactor This is
converted into electricity, and the fermentation remnant is dried after mechanical dehydra-
tion. The resultant process water is re-used for slurrying. . In principle, the process forms
a unit, after completion of which all products are incinerated completely (and is therefore
not comparable to an agricultural biogas plant, as I already outlined in my initial e-mail).
deli-
commi-
Dump
High-
pressure-
t t
process
water
Achieved environmental benefits
Waste
water
heat
heat
Cooling
purifi-
cation
block heat
d
Bio-
gasplant
Dewatering
residualmat
i l
ashes
Through lower consumption, re-use for slurrying and the discharge from the ammonia
stripper, the volume of water to be transported outside is significantly lower in comparison
to animal flour production. Combined, the effluent is analogous to that of conventional
waste fermentation plants. As a result of the conditioning required for the operation of the
dehydration device and ammonia stripper, COD concentrations reach 5 to 7 kg/m³ during
outflow.
The energy required for high pressure hydrolysis is obtained through power-heat cou-
pling on the basis of the biogas produced.
Cross media effects
With the exception of the effluent, which corresponds to that of a typical waste fermenta-
tion plant in terms of composition, all other material streams are channelled into thermal
conversion. The organic component of the animal by-products, which is converted into
biogas, is incinerated in a block-type thermal power station. The fermentation remnant
energy
biogas