The objective of the Aerobic Digester, “PDA”, is to study and understand aerobic digestion processes and to analyze their main parameters. The unit consists of a 20 l capacity reactor vessel with a tubular membrane made of plastic inside to separate the sludge. Wastewater to be treated enters the vessels pumped by a peristaltic pump. This unit includes a thermostatic bath to heat water up to 60 ºC. That water is driven by a pump through a coil inside the reactor. A suitable temperature for the microorganisms population employed in the aerobic digestion will be obtained. The greater amount of oxygen available in the environment in the aerobic digestion, the quicker the bacteria involved in the process will grow. Therefore, a compressor introduces a specific air flow into the reactor through a diffusion plate. The aerobic reactor includes a portable temperature, pH and dissolved oxygen meter to monitor the digestion.