*3.2.1 Composting process in CCC*

The CCC working protocol is based on the complete development of the process in three modular units of composting: the first unit corresponds to the contribution or feeding module in which citizens deposit the bio-waste; while the second and third units are used to carry out the transfers (**Figure 4**). These transfers homogenize the material and, therefore, increase the efficiency of the process, which allows the first unit to be left empty for new contributions by the participants. Depending on the number of participants or the volume of bio-waste to be assumed, the number of modular units required in each CCC is set up. In this way, three stages are distinguished from the operational and process point of view in community composting.

## *3.2.1.1 Stage 1: bio-waste input*

The neighbours deposit the bio-waste only in the modular units of feeding and immediately cover it with an equal volume of bulking agent. The master composters mix the materials so that the process begins. An intensive degradation phase takes place with a high oxygen demand, which is necessary for metabolic functions of the microorganisms. Large amounts of carbon dioxide and water vapour are released in this stage. The rise in temperature indicates that compost is developing properly.
