Abstract:

In this work, a practice session for anaerobic digestion of winery wastes was designed. The practice was based on the modeling of an anaerobic process for the treatment of winery wastes. The main objective of the practice was to introduce and teach some basic concepts of bio-energetic valorization by means of anaerobic digestion. For the design of the practice, a graphical programming software was used. The software was used because it was considered the most suitable option, based on the tool versatility, for the development of lab sessions since it allows to obtain an user-friendly and versatile interfaces, reducing decision and design times. A model based on a two-step (acidogenesis-methanization) anaerobic digestion was used Bernard et al. (2001). This model was used because its suitability for the wastes studied. The parameters of the model were estimated for common winery wastes and the wastes characteristics were used as input in the design stages, mainly COD, alkalinity, etc.

The main goals of the design stages were: On one hand, the design of virtual lab was used to help students to understand the influence of input variables such as COD, organic load, reactor volume, hydraulic retention time, influent flow rate, etc. On the other hand these results were used to design the experimental part of the laboratory practice, allowing the students to reach interesting results and conclusions in a single laboratory practice session.
With the laboratory sessions developed, the students run experiments for different values of the input variables and discuss the results evaluating the performance of the system, mainly in terms of time required to reach steady state, effluent COD, bio-gas flow rates (CO2 and CH4), heading value of the biogas, etc.

Additionally, students must answer a set of proposed questions. In this way, students learn how an anaerobic system works and how it responds to certain disturbances or changes in the operating conditions of the process and how they can proceed to achieve a fixed efficiency of the energetic bio-valorization treatment.

Keywords:

Energy, winery wastes, anaerobic digestion, bio-valorization.