Membrane cleaning is a key point for the implementation of membrane technologies in the dairy industry for proteins concentration. In this study, four ultrafiltration (UF) membranes with different molecular weight cut-offs (MWCOs) (5, 15, 30 and 50kDa) and materials (polyethersulfone and ceramics) were fouled with three different whey model solutions: bovine serum albumin (BSA), BSA plus CaCl2 and whey protein concentrate solution (Renylat 45). The purpose of the study was to evaluate the effect of ultrasounds (US) on the membrane cleaning efficiency. The influence of ultrasonic frequency and the US application modes (submerging the membrane module inside the US bath or applying US to the cleaning solution) were also evaluated. The experiments were performed in a laboratory plant which included the US equipment and the possibility of using two membrane modules (flat sheet and tubular). The fouling solution that caused the highest fouling degree for all the membranes was Renylat 45. Results demonstrated that membrane cleaning with US was effective and this effectiveness increased at lower frequencies. Although no significant differences were observed between the two different US applications modes tested, slightly higher cleaning efficiencies values placing the membrane module at the bottom of the tank were achieved.

This paper explains the steps carried out for the design of an educational innovation and the outcomes of its implementation. The innovation consists of integrating the contents of two courses (‘biological wastewater treatment’ and ‘bioprocesses applied to the treatment of wastes’) for the same academic year using project-based learning methodology to connect knowledge between subjects and to utilize transversal competences. Students from the second year of a chemical engineering master’s degree worked on an open-ended project based on a current environmental problem. This methodology lets the students properly acquire several transversal competences, such as ‘Design and project’, ‘Teamwork and leadership’, and ‘Effective communication’, which were evaluated with rubrics. However, according to the students’ perception, other skills, such as ‘Comprehension and integration, analysis and problem solving’, ‘Knowledge of contemporary problems’, and ‘Planning and time management’, were also worked on and improved. Based on the results from the matrix analysis and the Likert questionnaire, the organization and development of the activity were positively assessed, highlighting the importance of the lecturers’ feedback. The learning outcome in terms of knowledge integration was accomplished, reaching project marks 8.5–10 on a 0–10 scale.