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

above 70 o C due to insulation effects and on-going microbial activity. At these
temperatures many micro-organisms die or become dormant and the process
effectively stops until the micro-organisms can recover. Turning or aerating the
substrate when it approaches 60 o C can prevent this. If thermal kill does occur, the
substrate should be re-mixed using material from biologically active batches.
2.7. Retention time
The time period required to produce a composted organic material depends on many
factors, including user needs, moisture, temperature and the used raw materials.
Factors, which may slow the process down, include a high C:N ratio, low
temperature, insufficient aeration, lack of moisture, large particles and high
percentages of resistant materials such as wood. If the composted organic material
does not need to be completely stable for specific agricultural or biological
applications, it can be matured and finished where it is applied to land. The
composting period is often extended for composted organic products, which need to
be stable or particularly dry.
3. The need for sludge and BOW composting
The main objective of MOROCOMP project is to develop and establish an innovative
composting system for the treatment and reuse of sludge and other biodegradable
organic waste (BOW). The environmentally sound and commercially feasible
management of sewage sludge is a major issue that all European countries confront.
Sewage sludge arises from the processes of wastewater treatment and represents one
of the top priority waste streams. The most important reason that sludge generation,
disposal and recycling has been of particular concern lies in the fact that pollutants
contained in sewage sludge may impose potential risks on human health and on the
environment when applied to agricultural land without controlling its qualitative and
quantitative characteristics.
The selected substrate that was used as feedstock material into the bioreactor
comprised of primary sludge, green waste and manure of different origin (sheep,
cow). Sewage sludge was selected to be the primary raw composting material since
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