MOROCOMP (LIFE TCY05/MA000141) - Unit of Environmental ...

Summary
Within the framework of MOROCOMP project, an innovative composting system for
the effective treatment of sludge and other biodegradable organic waste was designed,
constructed, set up and operated at the experimental station SEMVA (Station
Expérimentale de Mise en Valeur Agricole) in Zemamra in the greater area of
Doukkala region in Morocco. This report aims to develop sludge composting and cocomposting
processes using various waste streams and to optimise the operation of
the system.
To determine the optimal course of composting four different composting trials have
been performed using a variety of waste such as primary and secondary sludge from
the WWTP of El Jadida city in Morocco, sugar beet leaves, straw residues, sheep and
cow manures in various ratios and under different operational conditions. Composting
trials have also been performed using effective additives such as zeolite and perlite for
the treatment of the aforementioned waste in order is to assist composting process
without partcipating in the biodegradation process. The selection of the experimental
set-up was determined according to the feedstock material and its characteristics
while at the end of each trial valuable feedback was obtained for the optimization of
the next composting trials. The temperature, moisture and oxygen content of the
substrate was closely monitored on a daily bases during composting while for the
evaluation of the processes complete physicochemical analyses have been performed
(i) to the raw material that was used as feedstock to the in-vessel composting
bioreactor (ii) to the leachates generated during composting (iii) to the substrate
throughout the duration of the composting processes and finally (iv) to the derived
product resulting from each composting trial.
With respect to the characteristics of the raw material used, sludges aquire relatively
low solid content ranging from 21.45% to 32.16% on dry basis due to the absence of
dewatering installations near the area where sludges were produced. This problem
was overcome with the addition of dried Biodegradable Organic Waste (BOW). In
addition, the feedstock material is rich in nutrients content and acquires low heavy
metals concentration conditions which favor the production of a good quality compost
at the end of each trial.
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