The second step of the process happens in the BAUER composting drum, which is installed in an insulated 40′ container. The solids are fed into the drum via a patented flap system so that the drum can be filled to over 70% of its volume. In the drum, the material is continuously mixed and subjected to an intense aerobic process, during which air is sucked out of the drum to remove moisture from the system. For an optimal composting process, the air temperature is kept at around 65–70°C. A homogeneous product is produced by a stable, continuous process.