Environmental Technologies and Eco-innovation in the Czech ...

simultaneously reduces ammonia emissions by at least 30% compared to stabling
with mattresses or straw.
In a plastic litter production line, solids are separated from raw cattle slurry that is
freed of pathogenic microorganisms 8 during aerobic controlled high-speed composting.
The composting process can be accelerated by adding suitable biotechnological
addtitives that increase the temperature in stowing and improve the hygienic
parameters of final products (see chapter 4.1 Biotechnological additives). Because
plastic litter complies with the required characteristics of high-grade compost, any
excess material may be used as a growing substrate.
Collective farm Krásná Hora nad Vltavou
a. s. has been making use of plastic litter
in dairy cow stables for five years. The
farmers’ coop uses plastic litter in its
farm in Petrovice by employing aerobic
high-speed composting in oblong heaps.
Throughout this entire period of using
plastic litter, microclimatic conditions
have been periodically monitored in
individual stables. It has been determined
that annual ammonia emissions per dairy
cow have decreased on average by 35%
compared to stabling with mattresses or
straw litter.
4.3.3 | Trigeneration
Controlled anaerobic fermentation 9 of biodegradable agricultural waste enables
the use of energy bound in waste for producing biogas with a methane content of
50–75%. Biogas is used in common cogeneration units for producing thermal
and electric energy (see Chapter 8.2.1 Biodegradable waste utilisation through
the anaerobic digestion process). Biogas may also be used for cooling through
trigeneration, which is a combined production of electric energy, heat and cold.
A cogeneration unit is supplemented with an absorption thermal convertor that
enables the conversion of thermal energy into cold. The main benefit of absorption
cooling is that thermal energy is used as output energy. It is cheaper than electric
energy (mainly used in classical compressor cooling). Trigeneration is especially
8 pathogenic organisms – disease-producing organisms
9 fermentation – a biotechnological process in which organic substances are gradually converted by the presence of microbial
enzymes (ferments) to more elementary substances
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