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

Table of contents
Figures......................................................................................................................................................5
Tables .......................................................................................................................................................6
Summary ..................................................................................................................................................8
1. Introduction to composting process ..............................................................................................11
2. Factors affecting the composting process .....................................................................................12
2.1. Oxygen and aeration ................................................................................................................12
2.2. Particle size, porosity, structure and texture.............................................................................13
2.3. Nutrients and the Carbon to Nitrogen ratio ..............................................................................13
2.4. pH.............................................................................................................................................14
2.5. Moisture ...................................................................................................................................14
2.6. Temperature .............................................................................................................................15
2.7. Retention time ..........................................................................................................................16
3. The need for sludge and BOW composting ..................................................................................16
4. Methodology and experimental procedures ..................................................................................18
4.1. Methods for sampling and analysis of the raw material...........................................................20
4.2. Composting mixtures ...............................................................................................................23
4.2.1. Pretreatment and preparation of the composting raw material.................................................24
4.2.2. Feeding the in-vessel bioreactor...............................................................................................24
4.3. Composting process control.....................................................................................................24
4.3.1. Programming the plc of the in-vessel bioreactor......................................................................24
4.3.2. Measuring the temperature of the substrate..............................................................................25
4.3.3. Measuring the moisture of the substrate...................................................................................25
4.3.4. Measuring the oxygen content of the substrate ........................................................................26
4.3.5. Reprogramming the plc of the in-vessel bioreactor..................................................................26
4.3.6. Monitoring and maintenance during composting.....................................................................26
4.3.7. Disruption and start up of the bioreactor operation..................................................................26
4.3.8. Restoration of malfunctions and maintenance of the bioreactor ..............................................26
4.4. Sampling and analysis of the substrate.....................................................................................27
4.5. Sampling and analysis of the substrate’s leachate....................................................................27
4.6. Removal and collection of the composting end product ..........................................................27
4.7. Sampling and analysis of the produced compost .....................................................................27
4.8. Preparing the system for the implementation of the next composting trial..............................28
4.9. Assessment of the composting trial in order to improve the next trial.....................................28
5. Results and discussion ..................................................................................................................29
5.1. Composting using primary sludge and green waste – 1st trial .................................................29
5.1.1. Sampling and analysis of the raw material...............................................................................29
5.1.2. Composition of the composting raw material ..........................................................................32
5.1.3. Pretreatment and preparation of the composting raw material.................................................32
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